Show erasure coding/rsa encryption if enabled for backup and copy

This option is mainly for the web GUI which currently doesn't have a way to
specify the passphrase to decrypt the RSA private key.

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,17 @@
+---
+name: Please use the official forum
+about: Please use the official forum instead of Github
+title: 'Please use the official forum'
+labels: ''
+assignees: ''
+
+---
+
+
+Please **use the [Duplicacy Forum](https://forum.duplicacy.com/)** when reporting bugs, making feature requests, asking for help or simply praising Duplicacy for its ease of use.
+
+We strongly encourage you to create an account on the forum and use that platform for discussion as there is a higher chance that someone there will talk to you. 
+
+There is a handful of people watching the Github Issues and we are in the process of moving **all** of them to the forum as well. Most likely you will not receive an answer here or it will be very slow and you will be pointed to the forum.
+
+We have already created a comprehensive [Guide](https://forum.duplicacy.com/t/duplicacy-user-guide/1197), and a [How-To](https://forum.duplicacy.com/c/how-to) category which stores more wisdom than these issues on Github.

ACKNOWLEDGEMENTS.md

@@ -14,3 +14,4 @@ Duplicacy is based on the following open source projects:
 |https://github.com/pcwizz/xattr            |  BSD-2-Clause |
 |https://github.com/minio/blake2b-simd      |  Apache-2.0 |
 |https://github.com/go-ole/go-ole           |  MIT |
+https://github.com/ncw/swift                |  MIT |

Gopkg.lock

@@ -7,17 +7,11 @@
   revision = "2d3a6656c17a60b0815b7e06ab0be04eacb6e613"
   version = "v0.16.0"
 
-[[projects]]
-  name = "github.com/Azure/azure-sdk-for-go"
-  packages = ["version"]
-  revision = "b7fadebe0e7f5c5720986080a01495bd8d27be37"
-  version = "v14.2.0"
-
 [[projects]]
   name = "github.com/Azure/go-autorest"
-  packages = ["autorest","autorest/adal","autorest/azure","autorest/date"]
-  revision = "0ae36a9e544696de46fdadb7b0d5fb38af48c063"
-  version = "v10.2.0"
+  packages = ["autorest","autorest/adal","autorest/azure","autorest/date","logger","version"]
+  revision = "9bc4033dd347c7f416fca46b2f42a043dc1fbdf6"
+  version = "v10.15.5"
 
 [[projects]]
   branch = "master"
@@ -27,9 +21,9 @@
 
 [[projects]]
   name = "github.com/aws/aws-sdk-go"
-  packages = ["aws","aws/awserr","aws/awsutil","aws/client","aws/client/metadata","aws/corehandlers","aws/credentials","aws/credentials/ec2rolecreds","aws/credentials/endpointcreds","aws/credentials/stscreds","aws/defaults","aws/ec2metadata","aws/endpoints","aws/request","aws/session","aws/signer/v4","internal/shareddefaults","private/protocol","private/protocol/query","private/protocol/query/queryutil","private/protocol/rest","private/protocol/restxml","private/protocol/xml/xmlutil","service/s3","service/sts"]
-  revision = "a32b1dcd091264b5dee7b386149b6cc3823395c9"
-  version = "v1.12.31"
+  packages = ["aws","aws/arn","aws/awserr","aws/awsutil","aws/client","aws/client/metadata","aws/corehandlers","aws/credentials","aws/credentials/ec2rolecreds","aws/credentials/endpointcreds","aws/credentials/processcreds","aws/credentials/stscreds","aws/csm","aws/defaults","aws/ec2metadata","aws/endpoints","aws/request","aws/session","aws/signer/v4","internal/context","internal/ini","internal/s3err","internal/sdkio","internal/sdkmath","internal/sdkrand","internal/sdkuri","internal/shareddefaults","internal/strings","internal/sync/singleflight","private/protocol","private/protocol/eventstream","private/protocol/eventstream/eventstreamapi","private/protocol/json/jsonutil","private/protocol/query","private/protocol/query/queryutil","private/protocol/rest","private/protocol/restxml","private/protocol/xml/xmlutil","service/s3","service/s3/internal/arn","service/sts","service/sts/stsiface"]
+  revision = "851d5ffb66720c2540cc68020d4d8708950686c8"
+  version = "v1.30.7"
 
 [[projects]]
   name = "github.com/bkaradzic/go-lz4"
@@ -40,14 +34,14 @@
 [[projects]]
   name = "github.com/dgrijalva/jwt-go"
   packages = ["."]
-  revision = "dbeaa9332f19a944acb5736b4456cfcc02140e29"
-  version = "v3.1.0"
+  revision = "06ea1031745cb8b3dab3f6a236daf2b0aa468b7e"
+  version = "v3.2.0"
 
 [[projects]]
   branch = "master"
   name = "github.com/gilbertchen/azure-sdk-for-go"
-  packages = ["storage"]
-  revision = "bbf89bd4d716c184f158d1e1428c2dbef4a18307"
+  packages = ["storage","version"]
+  revision = "8fd4663cab7c7c1c46d00449291c92ad23b0d0d9"
 
 [[projects]]
   branch = "master"
@@ -56,10 +50,9 @@
   revision = "1de0a1836ce9c3ae1bf737a0869c4f04f28a7f98"
 
 [[projects]]
-  branch = "master"
   name = "github.com/gilbertchen/go-dropbox"
   packages = ["."]
-  revision = "90711b603312b1f973f3a5da3793ac4f1e5c2f2a"
+  revision = "0baa9015ac2547d8b69b2e88c709aa90cfb8fbc1"
 
 [[projects]]
   name = "github.com/gilbertchen/go-ole"
@@ -71,7 +64,7 @@
   branch = "master"
   name = "github.com/gilbertchen/go.dbus"
   packages = ["."]
-  revision = "9e442e6378618c083fd3b85b703ffd202721fb17"
+  revision = "8591994fa32f1dbe3fa9486bc6f4d4361ac16649"
 
 [[projects]]
   branch = "master"
@@ -98,33 +91,33 @@
   revision = "68e7a6806b0137a396d7d05601d7403ae1abac58"
 
 [[projects]]
-  name = "github.com/go-ini/ini"
-  packages = ["."]
-  revision = "32e4c1e6bc4e7d0d8451aa6b75200d19e37a536a"
-  version = "v1.32.0"
+  branch = "master"
+  name = "github.com/golang/groupcache"
+  packages = ["lru"]
+  revision = "8c9f03a8e57eb486e42badaed3fb287da51807ba"
 
 [[projects]]
-  branch = "master"
   name = "github.com/golang/protobuf"
   packages = ["proto","protoc-gen-go/descriptor","ptypes","ptypes/any","ptypes/duration","ptypes/timestamp"]
-  revision = "1e59b77b52bf8e4b449a57e6f79f21226d571845"
+  revision = "84668698ea25b64748563aa20726db66a6b8d299"
+  version = "v1.3.5"
 
 [[projects]]
   name = "github.com/googleapis/gax-go"
-  packages = ["."]
-  revision = "317e0006254c44a0ac427cc52a0e083ff0b9622f"
-  version = "v2.0.0"
+  packages = [".","v2"]
+  revision = "c8a15bac9b9fe955bd9f900272f9a306465d28cf"
+  version = "v2.0.3"
 
 [[projects]]
   name = "github.com/jmespath/go-jmespath"
   packages = ["."]
-  revision = "0b12d6b5"
+  revision = "c2b33e84"
 
 [[projects]]
-  branch = "master"
   name = "github.com/kr/fs"
   packages = ["."]
-  revision = "2788f0dbd16903de03cb8186e5c7d97b69ad387b"
+  revision = "1455def202f6e05b95cc7bfc7e8ae67ae5141eba"
+  version = "v0.1.0"
 
 [[projects]]
   name = "github.com/marstr/guid"
@@ -139,22 +132,22 @@
   revision = "3f5f724cb5b182a5c278d6d3d55b40e7f8c2efb4"
 
 [[projects]]
-  branch = "master"
   name = "github.com/ncw/swift"
   packages = ["."]
-  revision = "ae9f0ea1605b9aa6434ed5c731ca35d83ba67c55"
+  revision = "3e1a09f21340e4828e7265aa89f4dc1495fa7ccc"
+  version = "v1.0.50"
 
 [[projects]]
   name = "github.com/pkg/errors"
   packages = ["."]
-  revision = "645ef00459ed84a119197bfb8d8205042c6df63d"
-  version = "v0.8.0"
+  revision = "614d223910a179a466c1767a985424175c39b465"
+  version = "v0.9.1"
 
 [[projects]]
   name = "github.com/pkg/sftp"
   packages = ["."]
-  revision = "98203f5a8333288eb3163b7c667d4260fe1333e9"
-  version = "1.0.0"
+  revision = "5616182052227b951e76d9c9b79a616c608bd91b"
+  version = "v1.11.0"
 
 [[projects]]
   name = "github.com/satori/go.uuid"
@@ -168,63 +161,68 @@
   packages = ["."]
   revision = "a98ad7ee00ec53921f08832bc06ecf7fd600e6a1"
 
+[[projects]]
+  name = "go.opencensus.io"
+  packages = [".","internal","internal/tagencoding","metric/metricdata","metric/metricproducer","plugin/ochttp","plugin/ochttp/propagation/b3","resource","stats","stats/internal","stats/view","tag","trace","trace/internal","trace/propagation","trace/tracestate"]
+  revision = "d835ff86be02193d324330acdb7d65546b05f814"
+  version = "v0.22.3"
+
 [[projects]]
   branch = "master"
   name = "golang.org/x/crypto"
-  packages = ["curve25519","ed25519","ed25519/internal/edwards25519","pbkdf2","ssh","ssh/agent","ssh/terminal"]
-  revision = "9f005a07e0d31d45e6656d241bb5c0f2efd4bc94"
+  packages = ["blowfish","chacha20","curve25519","ed25519","ed25519/internal/edwards25519","internal/subtle","pbkdf2","poly1305","ssh","ssh/agent","ssh/internal/bcrypt_pbkdf","ssh/terminal"]
+  revision = "056763e48d71961566155f089ac0f02f1dda9b5a"
 
 [[projects]]
   branch = "master"
   name = "golang.org/x/net"
-  packages = ["context","context/ctxhttp","http2","http2/hpack","idna","internal/timeseries","lex/httplex","trace"]
-  revision = "9dfe39835686865bff950a07b394c12a98ddc811"
+  packages = ["context","context/ctxhttp","http/httpguts","http2","http2/hpack","idna","internal/timeseries","trace"]
+  revision = "d3edc9973b7eb1fb302b0ff2c62357091cea9a30"
 
 [[projects]]
-  branch = "master"
   name = "golang.org/x/oauth2"
   packages = [".","google","internal","jws","jwt"]
-  revision = "f95fa95eaa936d9d87489b15d1d18b97c1ba9c28"
+  revision = "bf48bf16ab8d622ce64ec6ce98d2c98f916b6303"
 
 [[projects]]
   branch = "master"
   name = "golang.org/x/sys"
-  packages = ["unix","windows"]
-  revision = "82aafbf43bf885069dc71b7e7c2f9d7a614d47da"
+  packages = ["cpu","unix","windows"]
+  revision = "59c9f1ba88faf592b225274f69c5ef1e4ebacf82"
 
 [[projects]]
-  branch = "master"
   name = "golang.org/x/text"
-  packages = ["collate","collate/build","internal/colltab","internal/gen","internal/tag","internal/triegen","internal/ucd","language","secure/bidirule","transform","unicode/bidi","unicode/cldr","unicode/norm","unicode/rangetable"]
-  revision = "88f656faf3f37f690df1a32515b479415e1a6769"
+  packages = ["collate","collate/build","internal/colltab","internal/gen","internal/language","internal/language/compact","internal/tag","internal/triegen","internal/ucd","language","secure/bidirule","transform","unicode/bidi","unicode/cldr","unicode/norm","unicode/rangetable"]
+  revision = "342b2e1fbaa52c93f31447ad2c6abc048c63e475"
+  version = "v0.3.2"
 
 [[projects]]
-  branch = "master"
   name = "google.golang.org/api"
-  packages = ["drive/v3","gensupport","googleapi","googleapi/internal/uritemplates","googleapi/transport","internal","iterator","option","storage/v1","transport/http"]
-  revision = "17b5f22a248d6d3913171c1a557552ace0d9c806"
+  packages = ["drive/v3","googleapi","googleapi/transport","internal","internal/gensupport","internal/third_party/uritemplates","iterator","option","option/internaloption","storage/v1","transport/cert","transport/http","transport/http/internal/propagation"]
+  revision = "52f0532eadbcc6f6b82d6f5edf66e610d10bfde6"
+  version = "v0.21.0"
 
 [[projects]]
   name = "google.golang.org/appengine"
   packages = [".","internal","internal/app_identity","internal/base","internal/datastore","internal/log","internal/modules","internal/remote_api","internal/urlfetch","urlfetch"]
-  revision = "150dc57a1b433e64154302bdc40b6bb8aefa313a"
-  version = "v1.0.0"
+  revision = "971852bfffca25b069c31162ae8f247a3dba083b"
+  version = "v1.6.5"
 
 [[projects]]
   branch = "master"
   name = "google.golang.org/genproto"
-  packages = ["googleapis/api/annotations","googleapis/iam/v1","googleapis/rpc/status"]
-  revision = "891aceb7c239e72692819142dfca057bdcbfcb96"
+  packages = ["googleapis/api/annotations","googleapis/iam/v1","googleapis/rpc/status","googleapis/type/expr"]
+  revision = "baae70f3302d3efdff74db41e48a5d476d036906"
 
 [[projects]]
   name = "google.golang.org/grpc"
-  packages = [".","balancer","balancer/roundrobin","codes","connectivity","credentials","encoding","grpclb/grpc_lb_v1/messages","grpclog","internal","keepalive","metadata","naming","peer","resolver","resolver/dns","resolver/passthrough","stats","status","tap","transport"]
-  revision = "5a9f7b402fe85096d2e1d0383435ee1876e863d0"
-  version = "v1.8.0"
+  packages = [".","attributes","backoff","balancer","balancer/base","balancer/roundrobin","binarylog/grpc_binarylog_v1","codes","connectivity","credentials","credentials/internal","encoding","encoding/proto","grpclog","internal","internal/backoff","internal/balancerload","internal/binarylog","internal/buffer","internal/channelz","internal/envconfig","internal/grpclog","internal/grpcrand","internal/grpcsync","internal/grpcutil","internal/resolver/dns","internal/resolver/passthrough","internal/syscall","internal/transport","keepalive","metadata","naming","peer","resolver","serviceconfig","stats","status","tap"]
+  revision = "ac54eec90516cee50fc6b9b113b34628a85f976f"
+  version = "v1.28.1"
 
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "eff5ae2d9507f0d62cd2e5bdedebb5c59d64f70f476b087c01c35d4a5e1be72d"
+  inputs-digest = "e462352e0b0c726247078462e30a79330ac7a8b9dc62e9ed9d1e097b684224e9"
   solver-name = "gps-cdcl"
   solver-version = 1

Gopkg.toml

@@ -31,7 +31,7 @@
 
 [[constraint]]
   name = "github.com/aws/aws-sdk-go"
-  version = "1.12.31"
+  version = "1.30.7"
 
 [[constraint]]
   name = "github.com/bkaradzic/go-lz4"
@@ -46,8 +46,8 @@
   name = "github.com/gilbertchen/cli"
 
 [[constraint]]
-  branch = "master"
   name = "github.com/gilbertchen/go-dropbox"
+  revision = "0baa9015ac2547d8b69b2e88c709aa90cfb8fbc1"
 
 [[constraint]]
   name = "github.com/gilbertchen/go-ole"
@@ -75,7 +75,7 @@
 
 [[constraint]]
   name = "github.com/pkg/sftp"
-  version = "1.0.0"
+  version = "1.10.1"
 
 [[constraint]]
   branch = "master"
@@ -86,9 +86,13 @@
   name = "golang.org/x/net"
 
 [[constraint]]
-  branch = "master"
   name = "golang.org/x/oauth2"
+  revision = "bf48bf16ab8d622ce64ec6ce98d2c98f916b6303"
 
 [[constraint]]
-  branch = "master"
   name = "google.golang.org/api"
+  version = "0.21.0"
+
+[[constraint]]
+  name = "google.golang.org/grpc"
+  version = "1.28.0"

LICENSE.md

@@ -1,8 +1,7 @@
 Copyright © 2017 Acrosync LLC
 
 * Free for personal use or commercial trial
-* Non-trial commercial use requires per-user CLI licenses available from [duplicacy.com](https://duplicacy.com/buy) at a cost of $20 per year
-* A user is defined as the computer account that creates or edits the files to be backed up; if a backup contains files created or edited by multiple users for commercial purposes, one CLI license is required for each user
+* Non-trial commercial use requires per-computer CLI licenses available from [duplicacy.com](https://duplicacy.com/buy.html) at a cost of $50 per year
 * The computer with a valid commercial license for the GUI version may run the CLI version without a CLI license
 * CLI licenses are not required to restore or manage backups; only the backup command requires valid CLI licenses
 * Modification and redistribution are permitted, but commercial use of derivative works is subject to the same requirements of this license

README.md

@@ -1,28 +1,22 @@
 # Duplicacy: A lock-free deduplication cloud backup tool
 
-Duplicacy is a new generation cross-platform cloud backup tool based on the idea of [Lock-Free Deduplication](https://github.com/gilbertchen/duplicacy/wiki/Lock-Free-Deduplication).  It is the only cloud backup tool that allows multiple computers to back up to the same storage simultaneously without using any locks (thus readily amenable to various cloud storage services).
+Duplicacy is a new generation cross-platform cloud backup tool based on the idea of [Lock-Free Deduplication](https://github.com/gilbertchen/duplicacy/wiki/Lock-Free-Deduplication).  
 
-The repository hosts source code, design documents, and binary releases of the command line version.  There is also a Duplicacy GUI frontend built for Windows and Mac OS X available from https://duplicacy.com.
+This repository hosts source code, design documents, and binary releases of the command line version of Duplicacy.  There is also a Duplicacy GUI frontend built for Windows and Mac OS X available from https://duplicacy.com.
 
 There is a special edition of Duplicacy developed for VMware vSphere (ESXi) named [Vertical Backup](https://www.verticalbackup.com) that can back up virtual machine files on ESXi to local drives, network or cloud storages.
 
 ## Features
 
-Duplicacy currently supports major cloud storage providers (Amazon S3, Google Cloud Storage, Microsoft Azure, Dropbox, Backblaze B2, Google Drive, Microsoft OneDrive, and Hubic) and offers all essential features of a modern backup tool:
+There are 3 core advantages of Duplicacy over any other open-source or commercial backup tools:
 
-* Incremental backup: only back up what has been changed
-* Full snapshot: although each backup is incremental, it must behave like a full snapshot for easy restore and deletion
-* Deduplication: identical files must be stored as one copy (file-level deduplication), and identical parts from different files must be stored as one copy (block-level deduplication)
-* Encryption: encrypt not only file contents but also file paths, sizes, times, etc.
-* Deletion: every backup can be deleted independently without affecting others
-* Concurrent access: multiple clients can back up to the same storage at the same time
-* Snapshot migration: all or selected snapshots can be migrated from one storage to another
+* Duplicacy is the *only* cloud backup tool that allows multiple computers to back up to the same cloud storage, taking advantage of cross-computer deduplication whenever possible, without direct communication among them.  This feature literally turns any cloud storage server supporting only a basic set of file operations into a sophisticated deduplication-aware server.  
 
-The key idea of **[Lock-Free Deduplication](https://github.com/gilbertchen/duplicacy/wiki/Lock-Free-Deduplication)** can be summarized as follows:
+* Unlike other chunk-based backup tools where chunks are grouped into pack files and a chunk database is used to track which chunks are stored inside each pack file, Duplicacy takes a database-less approach where every chunk is saved independently using its hash as the file name to facilitate quick lookups.  The lack of a centralized chunk database not only makes the implementation less error-prone, but also produces a highly maintainable piece of software with plenty of room for development of new features and usability enhancements.
 
-* Use variable-size chunking algorithm to split files into chunks
-* Store each chunk in the storage using a file name derived from its hash, and rely on the file system API to manage chunks without using a centralized indexing database
-* Apply a *two-step fossil collection* algorithm to remove chunks that become unreferenced after a backup is deleted
+* Duplicacy is fast.  While the performance wasn't the top-priority design goal, Duplicacy has been shown to outperform other backup tools by a considerable margin, as indicated by the following results obtained from a [benchmarking experiment](https://github.com/gilbertchen/benchmarking) backing up the [Linux code base](https://github.com/torvalds/linux) using Duplicacy and 3 other open-source backup tools.
+
+[![Comparison of Duplicacy, restic, Attic, duplicity](https://github.com/gilbertchen/duplicacy/blob/master/images/duplicacy_benchmark_speed.png "Comparison of Duplicacy, restic, Attic, duplicity")](https://github.com/gilbertchen/benchmarking)
 
 ## Getting Started
 
@@ -32,104 +26,71 @@ The key idea of **[Lock-Free Deduplication](https://github.com/gilbertchen/dupli
 
 ## Storages
 
-With Duplicacy, you can back up files to local or networked drives, SFTP servers, or many cloud storage providers.  The following table compares the costs of all cloud storages supported by Duplicacy.
+Duplicacy currently provides the following storage backends:
 
-| Type         |   Storage (monthly)    |   Upload           |    Download    |    API Charge   |
-|:------------:|:-------------:|:------------------:|:--------------:|:-----------:|
-| Amazon S3    | $0.023/GB | free | $0.090/GB | [yes](https://aws.amazon.com/s3/pricing/) |
-| Wasabi       | $3.99 first 1TB <br> $0.0039/GB additional | free | $0.04/GB | no |
-| DigitalOcean Spaces| $5 first 250GB <br> $0.020/GB additional | free | first 1TB free <br> $0.01/GB additional| no |
-| Backblaze B2 | 10GB free <br> $0.005/GB | free | 1GB free/day <br> $0.02/GB | [yes](https://www.backblaze.com/b2/b2-transactions-price.html) |
-| Google Cloud Storage| $0.026/GB | free |$ 0.12/GB | [yes](https://cloud.google.com/storage/pricing) |
-| Google Drive | 15GB free <br> $1.99/100GB <br> $9.99/TB | free | free | no |
-| Microsoft Azure | $0.0184/GB | free | free | [yes](https://azure.microsoft.com/en-us/pricing/details/storage/blobs/) |
-| Microsoft OneDrive | 5GB free <br> $1.99/50GB <br> $5.83/TB | free | free | no |
-| Dropbox | 2GB free <br> $8.25/TB | free | free | no |
-| Hubic | 25GB free <br> €1/100GB <br> €5/10TB | free | free | no |
+* Local disk
+* SFTP
+* Dropbox
+* Amazon S3
+* Wasabi
+* DigitalOcean Spaces
+* Google Cloud Storage
+* Microsoft Azure
+* Backblaze B2
+* Google Drive
+* Microsoft OneDrive
+* Hubic
+* OpenStack Swift
+* WebDAV (under beta testing)
+* pcloud (via WebDAV)
+* Box.com (via WebDAV)
 
 Please consult the [wiki page](https://github.com/gilbertchen/duplicacy/wiki/Storage-Backends) on how to set up Duplicacy to work with each cloud storage.
 
-It should be noted that their performances vary a lot.  A [performance comparison](https://github.com/gilbertchen/cloud-storage-comparison) of these storages measured the running times (in seconds) of backing up and restoring the [Linux code base](https://github.com/torvalds/linux) as follows:
+For reference, the following chart shows the running times (in seconds) of backing up the [Linux code base](https://github.com/torvalds/linux) to each of those supported storages:
 
-| Storage              | initial backup | 2nd | 3rd | initial restore | 2nd | 3rd |
-|:--------------------:|:------:|:----:|:-----:|:----:|:-----:|:----:|
-| SFTP                 |  31.5  | 6.6  | 20.6  | 22.5  | 7.8  | 18.4 |
-| Amazon S3            |  41.1  | 5.9  | 21.9  | 27.7  | 7.6  | 23.5 |
-| Wasabi               |  38.7  | 5.7  | 31.7  | 25.7  | 6.5  | 23.2 | 
-| DigitalOcean Spaces  |  51.6  | 7.1  | 31.7  | 29.3  | 6.4  | 27.6 | 
-| Backblaze B2         |  106.7 | 24.0 | 88.2  | 67.9  | 14.4 | 39.1 | 
-| Google Cloud Storage |  76.9  | 11.9 | 33.1  | 39.5  | 9.9  | 26.2 | 
-| Google Drive         |  139.3 | 14.7 | 45.2  | 129.4 | 17.8 | 54.4 |
-| Microsoft Azure      |  35.0  | 5.4  | 20.4  | 30.7  | 7.1  | 21.5 | 
-| Microsoft OneDrive   |  250.0 | 31.6 | 80.2  | 333.4 | 26.2 | 82.0 | 
-| Dropbox              |  267.2 | 35.8 | 113.7 | 164.0 | 31.6 | 80.3 |
 
-For more details please visit https://github.com/gilbertchen/cloud-storage-comparison.
+[![Comparison of Cloud Storages](https://github.com/gilbertchen/duplicacy/blob/master/images/duplicacy_benchmark_cloud.png "Comparison of Cloud Storages")](https://github.com/gilbertchen/cloud-storage-comparison)
 
-## Feature Comparison with Other Backup Tools
+
+For complete benchmark results please visit https://github.com/gilbertchen/cloud-storage-comparison.
+
+## Comparison with Other Backup Tools
 
 [duplicity](http://duplicity.nongnu.org) works by applying the rsync algorithm (or more specific, the [librsync](https://github.com/librsync/librsync) library)
 to find the differences from previous backups and only then uploading the differences.  It is the only existing backup tool with extensive cloud support -- the [long list](http://duplicity.nongnu.org/duplicity.1.html#sect7) of storage backends covers almost every cloud provider one can think of.  However, duplicity's biggest flaw lies in its incremental model -- a chain of dependent backups starts with a full backup followed by a number of incremental ones, and ends when another full backup is uploaded.  Deleting one backup will render useless all the subsequent backups on the same chain.  Periodic full backups are required, in order to make previous backups disposable.
 
 [bup](https://github.com/bup/bup) also uses librsync to split files into chunks but save chunks in the git packfile format.  It doesn't support any cloud storage, or deletion of old backups.
 
-[Obnam](http://obnam.org) got the incremental backup model right in the sense that every incremental backup is actually a full snapshot.  Although Obnam also splits files into chunks, it does not adopt either the rsync algorithm or the variable-size chunking algorithm.  As a result, deletions or insertions of a few bytes will foil the
-[deduplication](http://obnam.org/faq/dedup).
-Deletion of old backups is possible, but no cloud storages are supported.
-Multiple clients can back up to the same storage, but only sequential access is granted by the [locking on-disk data structures](http://obnam.org/locking/).
-It is unclear if the lack of cloud backends is due to difficulties in porting the locking data structures to cloud storage APIs.
+[Duplicati](https://duplicati.com) is one of the first backup tools that adopt the chunk-based approach to split files into chunks which are then uploaded to the storage.  The chunk-based approach got the incremental backup model right in the sense that every incremental backup is actually a full snapshot.  As Duplicati splits files into fixed-size chunks,  deletions or insertions of a few bytes will foil the deduplication.  Cloud support is extensive, but multiple clients can't back up to the same storage location.
 
-[Attic](https://attic-backup.org) has been acclaimed by some as the [Holy Grail of backups](https://www.stavros.io/posts/holy-grail-backups).  It follows the same incremental backup model as Obnam, but embraces the variable-size chunk algorithm for better performance and better deduplication.  Deletions of old backup is also supported.  However, no cloud backends are implemented, as in Obnam.  Although concurrent backups from multiple clients to the same storage is in theory possible by the use of locking, it is
+[Attic](https://attic-backup.org) has been acclaimed by some as the [Holy Grail of backups](https://www.stavros.io/posts/holy-grail-backups).  It follows the same incremental backup model like Duplicati, but embraces the variable-size chunk algorithm for better performance and higher deduplication efficiency (not susceptible to byte insertion and deletion any more).  Deletions of old backup is also supported.  However, no cloud backends are implemented.  Although concurrent backups from multiple clients to the same storage is in theory possible by the use of locking, it is
 [not recommended](http://librelist.com/browser//attic/2014/11/11/backing-up-multiple-servers-into-a-single-repository/#e96345aa5a3469a87786675d65da492b) by the developer due to chunk indices being kept in a local cache.
-Concurrent access is not only a convenience; it is a necessity for better deduplication.  For instance, if multiple machines with the same OS installed can back up their entire drives to the same storage, only one copy of the system files needs to be stored, greatly reducing the storage space regardless of the number of machines.  Attic still adopts the traditional approach of using a centralized indexing database to manage chunks, and relies heavily on caching to improve performance.  The presence of exclusive locking makes it hard to be adapted for cloud storage APIs and reduces the level of deduplication.
+Concurrent access is not only a convenience; it is a necessity for better deduplication.  For instance, if multiple machines with the same OS installed can back up their entire drives to the same storage, only one copy of the system files needs to be stored, greatly reducing the storage space regardless of the number of machines.  Attic still adopts the traditional approach of using a centralized indexing database to manage chunks, and relies heavily on caching to improve performance.  The presence of exclusive locking makes it hard to be extended to cloud storages.
 
-[restic](https://restic.github.io) is a more recent addition.  It is worth mentioning here because, like Duplicacy, it is written in Go.  It uses a format similar to the git packfile format.  Multiple clients backing up to the same storage are still guarded by
-[locks](https://github.com/restic/restic/blob/master/doc/Design.md#locks).  A prune operation will therefore completely block all other clients connected to the storage from doing their regular backups.  Moreover, since most cloud storage services do not provide a locking service, the best effort is to use some basic file operations to simulate a lock, but distributed locking is known to be a hard problem and it is unclear how reliable restic's lock implementation is.  A faulty implementation may cause a prune operation to accidentally delete data still in use, resulting in unrecoverable data loss.  This is the exact problem that we avoided by taking the lock-free approach.
+[restic](https://restic.github.io) is a more recent addition. It uses a format similar to the git packfile format.  Multiple clients backing up to the same storage are still guarded by
+[locks](https://github.com/restic/restic/blob/master/doc/Design.md#locks), and because a chunk database is used, deduplication isn't real-time (different clients sharing the same files will upload different copies of the same chunks).  A prune operation will completely block all other clients connected to the storage from doing their regular backups.  Moreover, since most cloud storage services do not provide a locking service, the best effort is to use some basic file operations to simulate a lock, but distributed locking is known to be a hard problem and it is unclear how reliable restic's lock implementation is.  A faulty implementation may cause a prune operation to accidentally delete data still in use, resulting in unrecoverable data loss.  This is the exact problem that we avoided by taking the lock-free approach.
 
 
 The following table compares the feature lists of all these backup tools:
 
 
-| Feature/Tool       | duplicity | bup | Obnam             | Attic           | restic            | **Duplicacy** |
+| Feature/Tool       | duplicity | bup | Duplicati         | Attic           | restic            | **Duplicacy** |
 |:------------------:|:---------:|:---:|:-----------------:|:---------------:|:-----------------:|:-------------:|
 | Incremental Backup | Yes       | Yes | Yes               | Yes             | Yes               | **Yes**       |
 | Full Snapshot      | No        | Yes | Yes               | Yes             | Yes               | **Yes**       |
+| Compression        | Yes       | Yes | Yes               | Yes             | No                | **Yes**       |
 | Deduplication      | Weak      | Yes | Weak              | Yes             | Yes               | **Yes**       |
 | Encryption         | Yes       | Yes | Yes               | Yes             | Yes               | **Yes**       |
 | Deletion           | No        | No  | Yes               | Yes             | No                | **Yes**       |
-| Concurrent Access  | No        | No  | Exclusive locking | Not recommended | Exclusive locking | **Lock-free** |
-| Cloud Support      | Extensive | No  | No                | No              | S3, B2, OpenStack | **S3, GCS, Azure, Dropbox, Backblaze B2, Google Drive, OneDrive, and Hubic**|
+| Concurrent Access  | No        | No  | No                | Not recommended | Exclusive locking | **Lock-free** |
+| Cloud Support      | Extensive | No  | Extensive         | No              | Limited           | **Extensive** |
 | Snapshot Migration | No        | No  | No                | No              | No                | **Yes**       |
 
-
-## Performance Comparison with Other Backup Tools
-
-Duplicacy is not only more feature-rich but also faster than other backup tools.  The following table lists the running times in seconds of backing up the [Linux code base](https://github.com/torvalds/linux) using Duplicacy and 3 other tools.  Clearly Duplicacy is the fastest by a significant margin.
-
-
-|                    |   Duplicacy  |   restic   |   Attic    |  duplicity  |
-|:------------------:|:----------------:|:----------:|:----------:|:-----------:|
-| Initial backup | 13.7 | 20.7 | 26.9 | 44.2 |
-| 2nd backup | 4.8  |  8.0 | 15.4 | 19.5 |
-| 3rd backup | 6.9  | 11.9 | 19.6 | 29.8 |
-| 4th backup | 3.3  | 7.0  | 13.7 | 18.6 |
-| 5th backup | 9.9  | 11.4 | 19.9 | 28.0 |
-| 6th backup | 3.8  | 8.0  | 16.8 | 22.0 |
-| 7th backup | 5.1  | 7.8  | 14.3 | 21.6 |
-| 8th backup | 9.5  | 13.5 | 18.3 | 35.0 |
-| 9th backup | 4.3  | 9.0  | 15.7 | 24.9 |
-| 10th backup | 7.9 | 20.2 | 32.2 | 35.0 |
-| 11th backup | 4.6 | 9.1  | 16.8 | 28.1 |
-| 12th backup | 7.4 | 12.0 | 21.7 | 37.4 |
-
-
-For more details and other speed comparison results, please visit https://github.com/gilbertchen/benchmarking.  There you can also find test scripts that you can use to run your own experiments.
-
 ## License
 
 * Free for personal use or commercial trial
-* Non-trial commercial use requires per-user CLI licenses available from [duplicacy.com](https://duplicacy.com/buy) at a cost of $20 per year
-* A user is defined as the computer account that creates or edits the files to be backed up; if a backup contains files created or edited by multiple users for commercial purposes, one CLI license is required for each user
+* Non-trial commercial use requires per-computer CLI licenses available from [duplicacy.com](https://duplicacy.com/buy.html) at a cost of $50 per year
 * The computer with a valid commercial license for the GUI version may run the CLI version without a CLI license
 * CLI licenses are not required to restore or manage backups; only the backup command requires valid CLI licenses
 * Modification and redistribution are permitted, but commercial use of derivative works is subject to the same requirements of this license

duplicacy/duplicacy_main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"net/http"
 	"os"
 	"os/exec"
 	"os/signal"
@@ -16,7 +17,6 @@ import (
 	"runtime"
 	"strconv"
 	"strings"
-	"net/http"
 
 	_ "net/http/pprof"
 
@@ -32,6 +32,7 @@ const (
 )
 
 var ScriptEnabled bool
+var GitCommit = "unofficial"
 
 func getRepositoryPreference(context *cli.Context, storageName string) (repository string,
 	preference *duplicacy.Preference) {
@@ -71,6 +72,10 @@ func getRepositoryPreference(context *cli.Context, storageName string) (reposito
 	}
 
 	if storageName == "" {
+		if duplicacy.Preferences[0].RepositoryPath != "" {
+			repository = duplicacy.Preferences[0].RepositoryPath
+			duplicacy.LOG_INFO("REPOSITORY_SET", "Repository set to %s", repository)
+		}
 		return repository, &duplicacy.Preferences[0]
 	}
 
@@ -80,6 +85,12 @@ func getRepositoryPreference(context *cli.Context, storageName string) (reposito
 		duplicacy.LOG_ERROR("STORAGE_NONE", "No storage named '%s' is found", storageName)
 		return "", nil
 	}
+
+	if preference.RepositoryPath != "" {
+		repository = preference.RepositoryPath
+		duplicacy.LOG_INFO("REPOSITORY_SET", "Repository set to %s", repository)
+	}
+
 	return repository, preference
 }
 
@@ -148,7 +159,9 @@ func setGlobalOptions(context *cli.Context) {
 		}()
 	}
 
-
+	for _, logID := range context.GlobalStringSlice("suppress") {
+		duplicacy.SuppressLog(logID)
+	}
 
 	duplicacy.RunInBackground = context.GlobalBool("background")
 }
@@ -192,13 +205,29 @@ func runScript(context *cli.Context, storageName string, phase string) bool {
 	}
 
 	if err != nil {
-		duplicacy.LOG_WARN("SCRIPT_ERROR", "Failed to run script: %v", err)
+		duplicacy.LOG_ERROR("SCRIPT_ERROR", "Failed to run %s script: %v", script, err)
 		return false
 	}
 
 	return true
 }
 
+func loadRSAPrivateKey(keyFile string, passphrase string, preference *duplicacy.Preference, backupManager *duplicacy.BackupManager, resetPasswords bool) {
+	if keyFile == "" {
+		return
+	}
+
+	prompt := fmt.Sprintf("Enter the passphrase for %s:", keyFile)
+	if passphrase == "" {
+		passphrase = duplicacy.GetPassword(*preference, "rsa_passphrase", prompt, false, resetPasswords)
+		backupManager.LoadRSAPrivateKey(keyFile, passphrase)
+		duplicacy.SavePassword(*preference, "rsa_passphrase", passphrase)
+	} else {
+		backupManager.LoadRSAPrivateKey(keyFile, passphrase)
+	}
+
+}
+
 func initRepository(context *cli.Context) {
 	configRepository(context, true)
 }
@@ -293,11 +322,16 @@ func configRepository(context *cli.Context, init bool) {
 		}
 	}
 
+	repositoryPath := ""
+	if context.String("repository") != "" {
+		repositoryPath = context.String("repository")
+	}
 	preference := duplicacy.Preference{
-		Name:       storageName,
-		SnapshotID: snapshotID,
-		StorageURL: storageURL,
-		Encrypted:  context.Bool("encrypt"),
+		Name:           storageName,
+		SnapshotID:     snapshotID,
+		RepositoryPath: repositoryPath,
+		StorageURL:     storageURL,
+		Encrypted:      context.Bool("encrypt"),
 	}
 
 	storage := duplicacy.CreateStorage(preference, true, 1)
@@ -305,6 +339,11 @@ func configRepository(context *cli.Context, init bool) {
 	if preference.Encrypted {
 		prompt := fmt.Sprintf("Enter storage password for %s:", preference.StorageURL)
 		storagePassword = duplicacy.GetPassword(preference, "password", prompt, false, true)
+	} else {
+		if context.String("key") != "" {
+			duplicacy.LOG_ERROR("STORAGE_CONFIG", "RSA encryption can't be enabled with an unencrypted storage")
+			return
+		}
 	}
 
 	existingConfig, _, err := duplicacy.DownloadConfig(storage, storagePassword)
@@ -419,16 +458,38 @@ func configRepository(context *cli.Context, init bool) {
 		if iterations == 0 {
 			iterations = duplicacy.CONFIG_DEFAULT_ITERATIONS
 		}
+
+		dataShards := 0
+		parityShards := 0
+		shards := context.String("erasure-coding")
+		if shards != "" {
+			shardsRegex := regexp.MustCompile(`^([0-9]+):([0-9]+)$`)
+			matched := shardsRegex.FindStringSubmatch(shards)
+			if matched == nil {
+				duplicacy.LOG_ERROR("STORAGE_ERASURECODE", "Invalid erasure coding parameters: %s", shards)
+			} else {
+				dataShards, _ = strconv.Atoi(matched[1])
+				parityShards, _ = strconv.Atoi(matched[2])
+				if dataShards == 0 || dataShards > 256 || parityShards == 0 || parityShards > dataShards {
+					duplicacy.LOG_ERROR("STORAGE_ERASURECODE", "Invalid erasure coding parameters: %s", shards)
+				}
+			}
+		}
+
 		duplicacy.ConfigStorage(storage, iterations, compressionLevel, averageChunkSize, maximumChunkSize,
-			minimumChunkSize, storagePassword, otherConfig, bitCopy)
+			minimumChunkSize, storagePassword, otherConfig, bitCopy, context.String("key"), dataShards, parityShards)
 	}
 
 	duplicacy.Preferences = append(duplicacy.Preferences, preference)
 
 	duplicacy.SavePreferences()
 
+	if repositoryPath == "" {
+		repositoryPath = repository
+	}
+
 	duplicacy.LOG_INFO("REPOSITORY_INIT", "%s will be backed up to %s with id %s",
-		repository, preference.StorageURL, preference.SnapshotID)
+		repositoryPath, preference.StorageURL, preference.SnapshotID)
 }
 
 type TriBool struct {
@@ -514,6 +575,14 @@ func setPreference(context *cli.Context) {
 		newPreference.DoNotSavePassword = triBool.IsTrue()
 	}
 
+	if context.String("nobackup-file") != "" {
+		newPreference.NobackupFile = context.String("nobackup-file")
+	}
+
+	if context.String("filters") != "" {
+		newPreference.FiltersFile = context.String("filters")
+	}
+
 	key := context.String("key")
 	value := context.String("value")
 
@@ -628,7 +697,7 @@ func changePassword(context *cli.Context) {
 				duplicacy.LOG_INFO("CONFIG_CLEAN", "The local copy of the old config has been removed")
 			}
 		}
-	} ()
+	}()
 
 	err = storage.DeleteFile(0, "config")
 	if err != nil {
@@ -693,13 +762,14 @@ func backupRepository(context *cli.Context) {
 
 	dryRun := context.Bool("dry-run")
 	uploadRateLimit := context.Int("limit-rate")
+	enumOnly := context.Bool("enum-only")
 	storage.SetRateLimits(0, uploadRateLimit)
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, preference.NobackupFile, preference.FiltersFile)
 	duplicacy.SavePassword(*preference, "password", password)
 
 	backupManager.SetupSnapshotCache(preference.Name)
 	backupManager.SetDryRun(dryRun)
-	backupManager.Backup(repository, quickMode, threads, context.String("t"), showStatistics, enableVSS, vssTimeout)
+	backupManager.Backup(repository, quickMode, threads, context.String("t"), showStatistics, enableVSS, vssTimeout, enumOnly)
 
 	runScript(context, preference.Name, "post")
 }
@@ -761,31 +831,21 @@ func restoreRepository(context *cli.Context) {
 			pattern = pattern[1:]
 		}
 
-		if duplicacy.IsUnspecifiedFilter(pattern) {
-			pattern = "+" + pattern
-		}
-
-		if duplicacy.IsEmptyFilter(pattern) {
-			continue
-		}
-
-		if strings.HasPrefix(pattern, "i:") || strings.HasPrefix(pattern, "e:") {
-			valid, err := duplicacy.IsValidRegex(pattern[2:])
-			if !valid || err != nil {
-				duplicacy.LOG_ERROR("SNAPSHOT_FILTER", "Invalid regular expression encountered for filter: \"%s\", error: %v", pattern, err)
-			}
-		}
-
 		patterns = append(patterns, pattern)
-
 	}
 
+	patterns = duplicacy.ProcessFilterLines(patterns, make([]string, 0))
+
 	duplicacy.LOG_DEBUG("REGEX_DEBUG", "There are %d compiled regular expressions stored", len(duplicacy.RegexMap))
 
+	duplicacy.LOG_INFO("SNAPSHOT_FILTER", "Loaded %d include/exclude pattern(s)", len(patterns))
+
 	storage.SetRateLimits(context.Int("limit-rate"), 0)
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, preference.NobackupFile, preference.FiltersFile)
 	duplicacy.SavePassword(*preference, "password", password)
 
+	loadRSAPrivateKey(context.String("key"), context.String("key-passphrase"), preference, backupManager, false)
+
 	backupManager.SetupSnapshotCache(preference.Name)
 	backupManager.Restore(repository, revision, true, quickMode, threads, overwrite, deleteMode, setOwner, showStatistics, patterns)
 
@@ -823,7 +883,7 @@ func listSnapshots(context *cli.Context) {
 	tag := context.String("t")
 	revisions := getRevisions(context)
 
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
 	id := preference.SnapshotID
@@ -836,6 +896,9 @@ func listSnapshots(context *cli.Context) {
 	showFiles := context.Bool("files")
 	showChunks := context.Bool("chunks")
 
+	// list doesn't need to decrypt file chunks; but we need -key here so we can reset the passphrase for the private key
+	loadRSAPrivateKey(context.String("key"), "", preference, backupManager, resetPassword)
+
 	backupManager.SetupSnapshotCache(preference.Name)
 	backupManager.SnapshotManager.ListSnapshots(id, revisions, tag, showFiles, showChunks)
 
@@ -858,7 +921,12 @@ func checkSnapshots(context *cli.Context) {
 
 	runScript(context, preference.Name, "pre")
 
-	storage := duplicacy.CreateStorage(*preference, false, 1)
+	threads := context.Int("threads")
+	if threads < 1 {
+		threads = 1
+	}
+
+	storage := duplicacy.CreateStorage(*preference, false, threads)
 	if storage == nil {
 		return
 	}
@@ -871,9 +939,11 @@ func checkSnapshots(context *cli.Context) {
 	tag := context.String("t")
 	revisions := getRevisions(context)
 
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
+	loadRSAPrivateKey(context.String("key"), context.String("key-passphrase"), preference, backupManager, false)
+
 	id := preference.SnapshotID
 	if context.Bool("all") {
 		id = ""
@@ -884,11 +954,12 @@ func checkSnapshots(context *cli.Context) {
 	showStatistics := context.Bool("stats")
 	showTabular := context.Bool("tabular")
 	checkFiles := context.Bool("files")
+	checkChunks := context.Bool("chunks")
 	searchFossils := context.Bool("fossils")
 	resurrect := context.Bool("resurrect")
 
 	backupManager.SetupSnapshotCache(preference.Name)
-	backupManager.SnapshotManager.CheckSnapshots(id, revisions, tag, showStatistics, showTabular, checkFiles, searchFossils, resurrect)
+	backupManager.SnapshotManager.CheckSnapshots(id, revisions, tag, showStatistics, showTabular, checkFiles, checkChunks, searchFossils, resurrect, threads)
 
 	runScript(context, preference.Name, "post")
 }
@@ -926,9 +997,11 @@ func printFile(context *cli.Context) {
 		snapshotID = context.String("id")
 	}
 
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
+	loadRSAPrivateKey(context.String("key"), context.String("key-passphrase"), preference, backupManager, false)
+
 	backupManager.SetupSnapshotCache(preference.Name)
 
 	file := ""
@@ -982,11 +1055,13 @@ func diff(context *cli.Context) {
 	}
 
 	compareByHash := context.Bool("hash")
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
+	loadRSAPrivateKey(context.String("key"), context.String("key-passphrase"), preference, backupManager, false)
+
 	backupManager.SetupSnapshotCache(preference.Name)
-	backupManager.SnapshotManager.Diff(repository, snapshotID, revisions, path, compareByHash)
+	backupManager.SnapshotManager.Diff(repository, snapshotID, revisions, path, compareByHash, preference.NobackupFile, preference.FiltersFile)
 
 	runScript(context, preference.Name, "post")
 }
@@ -1025,7 +1100,7 @@ func showHistory(context *cli.Context) {
 
 	revisions := getRevisions(context)
 	showLocalHash := context.Bool("hash")
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
 	backupManager.SetupSnapshotCache(preference.Name)
@@ -1044,12 +1119,17 @@ func pruneSnapshots(context *cli.Context) {
 		os.Exit(ArgumentExitCode)
 	}
 
+	threads := context.Int("threads")
+	if threads < 1 {
+		threads = 1
+	}
+
 	repository, preference := getRepositoryPreference(context, "")
 
 	runScript(context, preference.Name, "pre")
 
 	duplicacy.LOG_INFO("STORAGE_SET", "Storage set to %s", preference.StorageURL)
-	storage := duplicacy.CreateStorage(*preference, false, 1)
+	storage := duplicacy.CreateStorage(*preference, false, threads)
 	if storage == nil {
 		return
 	}
@@ -1083,12 +1163,12 @@ func pruneSnapshots(context *cli.Context) {
 		os.Exit(ArgumentExitCode)
 	}
 
-	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password)
+	backupManager := duplicacy.CreateBackupManager(preference.SnapshotID, storage, repository, password, "", "")
 	duplicacy.SavePassword(*preference, "password", password)
 
 	backupManager.SetupSnapshotCache(preference.Name)
 	backupManager.SnapshotManager.PruneSnapshots(selfID, snapshotID, revisions, tags, retentions,
-		exhaustive, exclusive, ignoredIDs, dryRun, deleteOnly, collectOnly)
+		exhaustive, exclusive, ignoredIDs, dryRun, deleteOnly, collectOnly, threads)
 
 	runScript(context, preference.Name, "post")
 }
@@ -1123,10 +1203,12 @@ func copySnapshots(context *cli.Context) {
 		sourcePassword = duplicacy.GetPassword(*source, "password", "Enter source storage password:", false, false)
 	}
 
-	sourceManager := duplicacy.CreateBackupManager(source.SnapshotID, sourceStorage, repository, sourcePassword)
+	sourceManager := duplicacy.CreateBackupManager(source.SnapshotID, sourceStorage, repository, sourcePassword, "", "")
 	sourceManager.SetupSnapshotCache(source.Name)
 	duplicacy.SavePassword(*source, "password", sourcePassword)
 
+	loadRSAPrivateKey(context.String("key"), context.String("key-passphrase"), source, sourceManager, false)
+
 	_, destination := getRepositoryPreference(context, context.String("to"))
 
 	if destination.Name == source.Name {
@@ -1156,7 +1238,7 @@ func copySnapshots(context *cli.Context) {
 	destinationStorage.SetRateLimits(0, context.Int("upload-limit-rate"))
 
 	destinationManager := duplicacy.CreateBackupManager(destination.SnapshotID, destinationStorage, repository,
-		destinationPassword)
+		destinationPassword, "", "")
 	duplicacy.SavePassword(*destination, "password", destinationPassword)
 	destinationManager.SetupSnapshotCache(destination.Name)
 
@@ -1234,12 +1316,56 @@ func infoStorage(context *cli.Context) {
 
 	for _, dir := range dirs {
 		if len(dir) > 0 && dir[len(dir)-1] == '/' {
-			duplicacy.LOG_INFO("STORAGE_SNAPSHOT", "%s", dir[0:len(dir) - 1])
+			duplicacy.LOG_INFO("STORAGE_SNAPSHOT", "%s", dir[0:len(dir)-1])
 		}
 	}
 
 }
 
+func benchmark(context *cli.Context) {
+	setGlobalOptions(context)
+	defer duplicacy.CatchLogException()
+
+	fileSize := context.Int("file-size")
+	if fileSize == 0 {
+		fileSize = 256
+	}
+
+	chunkCount := context.Int("chunk-count")
+	if chunkCount == 0 {
+		chunkCount = 64
+	}
+
+	chunkSize := context.Int("chunk-size")
+	if chunkSize == 0 {
+		chunkSize = 4
+	}
+
+	downloadThreads := context.Int("download-threads")
+	if downloadThreads < 1 {
+		downloadThreads = 1
+	}
+
+	uploadThreads := context.Int("upload-threads")
+	if uploadThreads < 1 {
+		uploadThreads = 1
+	}
+
+	threads := downloadThreads
+	if threads < uploadThreads {
+		threads = uploadThreads
+	}
+
+	repository, preference := getRepositoryPreference(context, context.String("storage"))
+
+	duplicacy.LOG_INFO("STORAGE_SET", "Storage set to %s", preference.StorageURL)
+	storage := duplicacy.CreateStorage(*preference, false, threads)
+	if storage == nil {
+		return
+	}
+	duplicacy.Benchmark(repository, storage, int64(fileSize) * 1024 * 1024, chunkSize * 1024 * 1024, chunkCount, uploadThreads, downloadThreads)
+}
+
 func main() {
 
 	duplicacy.SetLoggingLevel(duplicacy.INFO)
@@ -1285,6 +1411,21 @@ func main() {
 					Usage:    "assign a name to the storage",
 					Argument: "<name>",
 				},
+				cli.StringFlag{
+					Name:     "repository",
+					Usage:    "initialize a new repository at the specified path rather than the current working directory",
+					Argument: "<path>",
+				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA public key to encrypt file chunks",
+					Argument: "<public key>",
+				},
+				cli.StringFlag{
+					Name:     "erasure-coding",
+					Usage:    "enable erasure coding to protect against storage corruption",
+					Argument: "<data shards>:<parity shards>",
+				},
 			},
 			Usage:     "Initialize the storage if necessary and the current directory as the repository",
 			ArgsUsage: "<snapshot id> <storage url>",
@@ -1324,7 +1465,7 @@ func main() {
 				},
 				cli.BoolFlag{
 					Name:  "vss",
-					Usage: "enable the Volume Shadow Copy service (Windows only)",
+					Usage: "enable the Volume Shadow Copy service (Windows and macOS using APFS only)",
 				},
 				cli.IntFlag{
 					Name:     "vss-timeout",
@@ -1337,6 +1478,10 @@ func main() {
 					Usage:    "backup to the specified storage instead of the default one",
 					Argument: "<storage name>",
 				},
+				cli.BoolFlag{
+					Name:  "enum-only",
+					Usage: "enumerate the repository recursively and then exit",
+				},
 			},
 			Usage:     "Save a snapshot of the repository to the storage",
 			ArgsUsage: " ",
@@ -1388,6 +1533,16 @@ func main() {
 					Usage:    "restore from the specified storage instead of the default one",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks",
+					Argument: "<private key>",
+				},
+				cli.StringFlag{
+					Name:     "key-passphrase",
+					Usage:    "the passphrase to decrypt the RSA private key",
+					Argument: "<private key passphrase>",
+				},
 			},
 			Usage:     "Restore the repository to a previously saved snapshot",
 			ArgsUsage: "[--] [pattern] ...",
@@ -1433,6 +1588,11 @@ func main() {
 					Usage:    "retrieve snapshots from the specified storage",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks",
+					Argument: "<private key>",
+				},
 			},
 			Usage:     "List snapshots",
 			ArgsUsage: " ",
@@ -1472,6 +1632,10 @@ func main() {
 					Name:  "files",
 					Usage: "verify the integrity of every file",
 				},
+				cli.BoolFlag{
+					Name:  "chunks",
+					Usage: "verify the integrity of every chunk",
+				},
 				cli.BoolFlag{
 					Name:  "stats",
 					Usage: "show deduplication statistics (imply -all and all revisions)",
@@ -1485,6 +1649,22 @@ func main() {
 					Usage:    "retrieve snapshots from the specified storage",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks",
+					Argument: "<private key>",
+				},
+				cli.StringFlag{
+					Name:     "key-passphrase",
+					Usage:    "the passphrase to decrypt the RSA private key",
+					Argument: "<private key passphrase>",
+				},
+				cli.IntFlag{
+					Name:     "threads",
+					Value:    1,
+					Usage:    "number of threads used to verify chunks",
+					Argument: "<n>",
+				},
 			},
 			Usage:     "Check the integrity of snapshots",
 			ArgsUsage: " ",
@@ -1508,6 +1688,16 @@ func main() {
 					Usage:    "retrieve the file from the specified storage",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks",
+					Argument: "<private key>",
+				},
+				cli.StringFlag{
+					Name:     "key-passphrase",
+					Usage:    "the passphrase to decrypt the RSA private key",
+					Argument: "<private key passphrase>",
+				},
 			},
 			Usage:     "Print to stdout the specified file, or the snapshot content if no file is specified",
 			ArgsUsage: "[<file>]",
@@ -1536,6 +1726,16 @@ func main() {
 					Usage:    "retrieve files from the specified storage",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks",
+					Argument: "<private key>",
+				},
+				cli.StringFlag{
+					Name:     "key-passphrase",
+					Usage:    "the passphrase to decrypt the RSA private key",
+					Argument: "<private key passphrase>",
+				},
 			},
 			Usage:     "Compare two snapshots or two revisions of a file",
 			ArgsUsage: "[<file>]",
@@ -1627,6 +1827,12 @@ func main() {
 					Usage:    "prune snapshots from the specified storage",
 					Argument: "<storage name>",
 				},
+				cli.IntFlag{
+					Name:     "threads",
+					Value:    1,
+					Usage:    "number of threads used to prune unreferenced chunks",
+					Argument: "<n>",
+				},
 			},
 			Usage:     "Prune snapshots by revision, tag, or retention policy",
 			ArgsUsage: " ",
@@ -1686,8 +1892,23 @@ func main() {
 					Argument: "<storage name>",
 				},
 				cli.BoolFlag{
-					Name:     "bit-identical",
-					Usage:    "(when using -copy) make the new storage bit-identical to also allow rsync etc.",
+					Name:  "bit-identical",
+					Usage: "(when using -copy) make the new storage bit-identical to also allow rsync etc.",
+				},
+				cli.StringFlag{
+					Name:     "repository",
+					Usage:    "specify the path of the repository (instead of the current working directory)",
+					Argument: "<path>",
+				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA public key to encrypt file chunks",
+					Argument: "<public key>",
+				},
+				cli.StringFlag{
+					Name:     "erasure-coding",
+					Usage:    "enable erasure coding to protect against storage corruption",
+					Argument: "<data shards>:<parity shards>",
 				},
 			},
 			Usage:     "Add an additional storage to be used for the existing repository",
@@ -1722,6 +1943,12 @@ func main() {
 					Value: &TriBool{},
 					Arg:   "true",
 				},
+				cli.StringFlag{
+					Name:     "nobackup-file",
+					Usage:    "Directories containing a file with this name will not be backed up",
+					Argument: "<file name>",
+					Value:    "",
+				},
 				cli.StringFlag{
 					Name:  "key",
 					Usage: "add a key/password whose value is supplied by the -value option",
@@ -1735,6 +1962,11 @@ func main() {
 					Usage:    "use the specified storage instead of the default one",
 					Argument: "<storage name>",
 				},
+				cli.StringFlag{
+					Name:     "filters",
+					Usage:    "specify the path of the filters file containing include/exclude patterns",
+					Argument: "<file path>",
+				},
 			},
 			Usage:     "Change the options for the default or specified storage",
 			ArgsUsage: " ",
@@ -1778,9 +2010,19 @@ func main() {
 				cli.IntFlag{
 					Name:     "threads",
 					Value:    1,
-					Usage:    "number of downloading threads",
+					Usage:    "number of uploading threads",
 					Argument: "<n>",
 				},
+				cli.StringFlag{
+					Name:     "key",
+					Usage:    "the RSA private key to decrypt file chunks from the source storage",
+					Argument: "<private key>",
+				},
+				cli.StringFlag{
+					Name:     "key-passphrase",
+					Usage:    "the passphrase to decrypt the RSA private key",
+					Argument: "<private key passphrase>",
+				},
 			},
 			Usage:     "Copy snapshots between compatible storages",
 			ArgsUsage: " ",
@@ -1813,6 +2055,45 @@ func main() {
 			ArgsUsage: "<storage url>",
 			Action:    infoStorage,
 		},
+
+		{
+			Name: "benchmark",
+			Flags: []cli.Flag{
+				cli.IntFlag{
+					Name:     "file-size",
+					Usage:    "the size of the local file to write to and read from (in MB, default to 256)",
+					Argument: "<size>",
+				},
+				cli.IntFlag{
+					Name:     "chunk-count",
+					Usage:    "the number of chunks to upload and download (default to 64)",
+					Argument: "<count>",
+				},
+				cli.IntFlag{
+					Name:     "chunk-size",
+					Usage:    "the size of chunks to upload and download (in MB, default to 4)",
+					Argument: "<size>",
+				},
+				cli.IntFlag{
+					Name:     "upload-threads",
+					Usage:    "the number of upload threads (default to 1)",
+					Argument: "<n>",
+				},
+				cli.IntFlag{
+					Name:     "download-threads",
+					Usage:    "the number of download threads (default to 1)",
+					Argument: "<n>",
+				},
+				cli.StringFlag{
+					Name:     "storage",
+					Usage:    "run the download/upload test agaist the specified storage",
+					Argument: "<storage name>",
+				},
+			},
+			Usage:     "Run a set of benchmarks to test download and upload speeds",
+			ArgsUsage: " ",
+			Action:    benchmark,
+		},
 	}
 
 	app.Flags = []cli.Flag{
@@ -1847,8 +2128,13 @@ func main() {
 			Argument: "<address:port>",
 		},
 		cli.StringFlag{
-			Name:	"comment",
-			Usage:	"add a comment to identify the process",
+			Name:  "comment",
+			Usage: "add a comment to identify the process",
+		},
+		cli.StringSliceFlag{
+			Name:  "suppress, s",
+			Usage: "suppress logs with the specified id",
+			Argument: "<id>",
 		},
 	}
 
@@ -1856,13 +2142,13 @@ func main() {
 	app.Name = "duplicacy"
 	app.HelpName = "duplicacy"
 	app.Usage = "A new generation cloud backup tool based on lock-free deduplication"
-	app.Version = "2.1.0"
+	app.Version = "2.6.2" + " (" + GitCommit + ")"
 
 	// If the program is interrupted, call the RunAtError function.
 	c := make(chan os.Signal, 1)
 	signal.Notify(c, os.Interrupt)
 	go func() {
-		for _ = range c {
+		for range c {
 			duplicacy.RunAtError()
 			os.Exit(1)
 		}

src/duplicacy_acdstorage.go

@@ -55,7 +55,7 @@ func CreateACDStorage(tokenFile string, storagePath string, threads int) (storag
 				return nil, err
 			}
 		} else if !isDir {
-			return nil, fmt.Errorf("%s/%s is not a directory", storagePath+"/"+dir)
+			return nil, fmt.Errorf("%s is not a directory", storagePath+"/"+dir)
 		}
 		storage.idCache[dir] = dirID
 	}

src/duplicacy_azurestorage.go

@@ -104,7 +104,7 @@ func (azureStorage *AzureStorage) ListFiles(threadIndex int, dir string) (files
 
 	if dir == "snapshots/" {
 
-		for subDir, _ := range subDirs {
+		for subDir := range subDirs {
 			files = append(files, subDir)
 		}
 
@@ -166,9 +166,21 @@ func (storage *AzureStorage) DownloadFile(threadIndex int, filePath string, chun
 
 // UploadFile writes 'content' to the file at 'filePath'.
 func (storage *AzureStorage) UploadFile(threadIndex int, filePath string, content []byte) (err error) {
-	reader := CreateRateLimitedReader(content, storage.UploadRateLimit/len(storage.containers))
-	blob := storage.containers[threadIndex].GetBlobReference(filePath)
-	return blob.CreateBlockBlobFromReader(reader, nil)
+
+	tries := 0
+
+	for {
+		reader := CreateRateLimitedReader(content, storage.UploadRateLimit/len(storage.containers))
+		blob := storage.containers[threadIndex].GetBlobReference(filePath)
+		err = blob.CreateBlockBlobFromReader(reader, nil)
+
+		if err == nil || !strings.Contains(err.Error(), "write: broken pipe") || tries >= 3 {
+			return err
+		}
+
+		LOG_INFO("AZURE_RETRY", "Connection unexpectedly terminated: %v; retrying", err)
+		tries++
+	}
 
 }
 

src/duplicacy_b2client.go

@@ -5,19 +5,22 @@
 package duplicacy
 
 import (
-	"bytes"
-	"crypto/sha1"
-	"encoding/base64"
-	"encoding/hex"
-	"encoding/json"
-	"fmt"
 	"io"
-	"io/ioutil"
-	"math/rand"
-	"net/http"
+	"os"
+	"fmt"
+	"bytes"
+	"time"
+	"sync"
 	"strconv"
 	"strings"
-	"time"
+	"net/url"
+	"net/http"
+	"math/rand"
+	"io/ioutil"
+	"crypto/sha1"
+	"encoding/hex"
+	"encoding/json"
+	"encoding/base64"
 )
 
 type B2Error struct {
@@ -39,66 +42,115 @@ var B2AuthorizationURL = "https://api.backblazeb2.com/b2api/v1/b2_authorize_acco
 
 type B2Client struct {
 	HTTPClient         *http.Client
+
 	AccountID          string
+	ApplicationKeyID   string
 	ApplicationKey     string
+	BucketName         string
+	BucketID           string
+	StorageDir         string
+
+	Lock               sync.Mutex
 	AuthorizationToken string
 	APIURL             string
 	DownloadURL        string
-	BucketName         string
-	BucketID           string
+	IsAuthorized       bool
 
-	UploadURL   string
-	UploadToken string
+	UploadURLs         []string
+	UploadTokens       []string
 
-	TestMode bool
+	Threads            int
+	MaximumRetries     int
+	TestMode           bool
+
+	LastAuthorizationTime int64
 }
 
-func NewB2Client(accountID string, applicationKey string) *B2Client {
+// URL encode the given path but keep the slashes intact
+func B2Escape(path string) string {
+	var components []string
+	for _, c := range strings.Split(path, "/") {
+		components = append(components, url.QueryEscape(c))
+	}
+	return strings.Join(components, "/")
+}
+
+func NewB2Client(applicationKeyID string, applicationKey string, downloadURL string, storageDir string, threads int) *B2Client {
+
+	for storageDir != "" && storageDir[0] == '/' {
+		storageDir = storageDir[1:]
+	}
+
+	if storageDir != "" && storageDir[len(storageDir) - 1] != '/' {
+		storageDir += "/"
+	}
+
+	maximumRetries := 15
+	if value, found := os.LookupEnv("DUPLICACY_B2_RETRIES"); found && value != "" {
+		maximumRetries, _ = strconv.Atoi(value)
+		LOG_INFO("B2_RETRIES", "Setting maximum retries for B2 to %d", maximumRetries)
+	}
+
 	client := &B2Client{
-		HTTPClient:     http.DefaultClient,
-		AccountID:      accountID,
-		ApplicationKey: applicationKey,
+		HTTPClient:       http.DefaultClient,
+		ApplicationKeyID: applicationKeyID,
+		ApplicationKey:   applicationKey,
+		DownloadURL:      downloadURL,
+		StorageDir:       storageDir,
+		UploadURLs:       make([]string, threads),
+		UploadTokens:     make([]string, threads),
+		Threads:          threads,
+		MaximumRetries:   maximumRetries,
 	}
 	return client
 }
 
-func (client *B2Client) retry(backoff int, response *http.Response) int {
+func (client *B2Client) getAPIURL() string {
+	client.Lock.Lock()
+	defer client.Lock.Unlock()
+	return client.APIURL
+}
+
+func (client *B2Client) getDownloadURL() string {
+	client.Lock.Lock()
+	defer client.Lock.Unlock()
+	return client.DownloadURL
+}
+
+func (client *B2Client) retry(retries int, response *http.Response) int {
 	if response != nil {
 		if backoffList, found := response.Header["Retry-After"]; found && len(backoffList) > 0 {
 			retryAfter, _ := strconv.Atoi(backoffList[0])
 			if retryAfter >= 1 {
 				time.Sleep(time.Duration(retryAfter) * time.Second)
-				return 0
+				return 1
 			}
 		}
 	}
-	if backoff == 0 {
-		backoff = 1
-	} else {
-		backoff *= 2
+
+	if retries >= client.MaximumRetries + 1 {
+		return 0
 	}
-	time.Sleep(time.Duration(backoff) * time.Second)
-	return backoff
+	retries++
+	delay := 1 << uint(retries)
+	if delay > 64 {
+		delay = 64
+	}
+	delayInSeconds := (rand.Float32() + 1.0) * float32(delay) / 2.0
+
+	time.Sleep(time.Duration(delayInSeconds) * time.Second)
+	return retries
 }
 
-func (client *B2Client) call(url string, method string, requestHeaders map[string]string, input interface{}) (io.ReadCloser, http.Header, int64, error) {
-
-	switch method {
-	case http.MethodGet:
-		break
-	case http.MethodHead:
-		break
-	case http.MethodPost:
-		break
-	default:
-		return nil, nil, 0, fmt.Errorf("unhandled http request method: " + method)
-	}
+func (client *B2Client) call(threadIndex int, requestURL string, method string, requestHeaders map[string]string, input interface{}) (
+	                         io.ReadCloser, http.Header, int64, error) {
 
 	var response *http.Response
 
-	backoff := 0
-	for i := 0; i < 8; i++ {
-		var inputReader *bytes.Reader
+	retries := 0
+	for {
+		var inputReader io.Reader
+		isUpload := false
 
 		switch input.(type) {
 		default:
@@ -107,21 +159,43 @@ func (client *B2Client) call(url string, method string, requestHeaders map[strin
 				return nil, nil, 0, err
 			}
 			inputReader = bytes.NewReader(jsonInput)
-		case []byte:
-			inputReader = bytes.NewReader(input.([]byte))
 		case int:
 			inputReader = bytes.NewReader([]byte(""))
+		case []byte:
+			isUpload = true
+			inputReader = bytes.NewReader(input.([]byte))
+		case *RateLimitedReader:
+			isUpload = true
+			rateLimitedReader := input.(*RateLimitedReader)
+			rateLimitedReader.Reset()
+			inputReader = rateLimitedReader
 		}
 
-		request, err := http.NewRequest(method, url, inputReader)
+
+		if isUpload {
+			if client.UploadURLs[threadIndex] == "" || client.UploadTokens[threadIndex] == "" {
+				err := client.getUploadURL(threadIndex)
+				if err != nil {
+					return nil, nil, 0, err
+				}
+			}
+			requestURL = client.UploadURLs[threadIndex]
+		}
+
+		request, err := http.NewRequest(method, requestURL, inputReader)
 		if err != nil {
 			return nil, nil, 0, err
 		}
 
-		if url == B2AuthorizationURL {
-			request.Header.Set("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(client.AccountID+":"+client.ApplicationKey)))
+		if requestURL == B2AuthorizationURL {
+			request.Header.Set("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(client.ApplicationKeyID+":"+client.ApplicationKey)))
+		} else if isUpload {
+			request.ContentLength, _ = strconv.ParseInt(requestHeaders["Content-Length"], 10, 64)
+			request.Header.Set("Authorization", client.UploadTokens[threadIndex])
 		} else {
+			client.Lock.Lock()
 			request.Header.Set("Authorization", client.AuthorizationToken)
+			client.Lock.Unlock()
 		}
 
 		if requestHeaders != nil {
@@ -132,7 +206,9 @@ func (client *B2Client) call(url string, method string, requestHeaders map[strin
 
 		if client.TestMode {
 			r := rand.Float32()
-			if r < 0.5 {
+			if r < 0.5 && isUpload {
+				request.Header.Set("X-Bz-Test-Mode", "fail_some_uploads")
+			} else if r < 0.75 {
 				request.Header.Set("X-Bz-Test-Mode", "expire_some_account_authorization_tokens")
 			} else {
 				request.Header.Set("X-Bz-Test-Mode", "force_cap_exceeded")
@@ -141,28 +217,51 @@ func (client *B2Client) call(url string, method string, requestHeaders map[strin
 
 		response, err = client.HTTPClient.Do(request)
 		if err != nil {
-			if url != B2AuthorizationURL {
-				LOG_DEBUG("BACKBLAZE_CALL", "URL request '%s' returned an error: %v", url, err)
-				backoff = client.retry(backoff, response)
-				continue
+
+			// Don't retry when the first authorization request fails
+			if requestURL == B2AuthorizationURL && !client.IsAuthorized {
+				return nil, nil, 0, err
 			}
-			return nil, nil, 0, err
+
+			LOG_TRACE("BACKBLAZE_CALL", "[%d] URL request '%s' returned an error: %v", threadIndex, requestURL, err)
+
+			retries = client.retry(retries, response)
+			if retries <= 0 {
+				return nil, nil, 0, err
+			}
+
+			// Clear the upload url to requrest a new one on retry
+			if isUpload {
+				client.UploadURLs[threadIndex] = ""
+				client.UploadTokens[threadIndex] = ""
+			}
+			continue
+
 		}
 
 		if response.StatusCode < 300 {
 			return response.Body, response.Header, response.ContentLength, nil
 		}
 
-		LOG_DEBUG("BACKBLAZE_CALL", "URL request '%s %s' returned status code %d", method, url, response.StatusCode)
+		e := &B2Error{}
+		if err := json.NewDecoder(response.Body).Decode(e); err != nil {
+			LOG_TRACE("BACKBLAZE_CALL", "[%d] URL request '%s %s' returned status code %d", threadIndex, method, requestURL, response.StatusCode)
+		} else {
+			LOG_TRACE("BACKBLAZE_CALL", "[%d] URL request '%s %s' returned %d %s", threadIndex, method, requestURL, response.StatusCode, e.Message)
+		}
 
-		io.Copy(ioutil.Discard, response.Body)
 		response.Body.Close()
+
 		if response.StatusCode == 401 {
-			if url == B2AuthorizationURL {
+			if requestURL == B2AuthorizationURL {
 				return nil, nil, 0, fmt.Errorf("Authorization failure")
 			}
-			client.AuthorizeAccount()
-			continue
+
+			// Attempt authorization again.  If authorization is actually not done, run the random backoff
+			_, allowed := client.AuthorizeAccount(threadIndex)
+			if allowed {
+				continue
+			}
 		} else if response.StatusCode == 403 {
 			if !client.TestMode {
 				return nil, nil, 0, fmt.Errorf("B2 cap exceeded")
@@ -175,32 +274,21 @@ func (client *B2Client) call(url string, method string, requestHeaders map[strin
 		} else if response.StatusCode == 416 {
 			if http.MethodHead == method {
 				// 416 Requested Range Not Satisfiable
-				return nil, nil, 0, fmt.Errorf("URL request '%s' returned status code %d", url, response.StatusCode)
+				return nil, nil, 0, fmt.Errorf("URL request '%s' returned %d %s", requestURL, response.StatusCode, e.Message)
 			}
-		} else if response.StatusCode == 429 || response.StatusCode == 408 {
-			backoff = client.retry(backoff, response)
-			continue
-		} else if response.StatusCode >= 500 && response.StatusCode <= 599 {
-			backoff = client.retry(backoff, response)
-			continue
-		} else {
-			LOG_INFO("BACKBLAZE_CALL", "URL request '%s' returned status code %d", url, response.StatusCode)
-			backoff = client.retry(backoff, response)
-			continue
 		}
 
-		defer response.Body.Close()
-
-		e := &B2Error{}
-
-		if err := json.NewDecoder(response.Body).Decode(e); err != nil {
-			return nil, nil, 0, err
+		retries = client.retry(retries, response)
+		if retries <= 0 {
+			return nil, nil, 0, fmt.Errorf("URL request '%s' returned %d %s", requestURL, response.StatusCode, e.Message)
 		}
 
-		return nil, nil, 0, e
+		if isUpload {
+			client.UploadURLs[threadIndex] = ""
+			client.UploadTokens[threadIndex] = ""
+		}
 	}
 
-	return nil, nil, 0, fmt.Errorf("Maximum backoff reached")
 }
 
 type B2AuthorizeAccountOutput struct {
@@ -210,11 +298,18 @@ type B2AuthorizeAccountOutput struct {
 	DownloadURL        string
 }
 
-func (client *B2Client) AuthorizeAccount() (err error) {
+func (client *B2Client) AuthorizeAccount(threadIndex int) (err error, allowed bool) {
+	client.Lock.Lock()
+	defer client.Lock.Unlock()
 
-	readCloser, _, _, err := client.call(B2AuthorizationURL, http.MethodPost, nil, make(map[string]string))
+	// Don't authorize if the previous one was done less than 30 seconds ago
+	if client.LastAuthorizationTime != 0 && client.LastAuthorizationTime > time.Now().Unix() - 30 {
+		return nil, false
+	}
+
+	readCloser, _, _, err := client.call(threadIndex, B2AuthorizationURL, http.MethodPost, nil, make(map[string]string))
 	if err != nil {
-		return err
+		return err, true
 	}
 
 	defer readCloser.Close()
@@ -222,18 +317,28 @@ func (client *B2Client) AuthorizeAccount() (err error) {
 	output := &B2AuthorizeAccountOutput{}
 
 	if err = json.NewDecoder(readCloser).Decode(&output); err != nil {
-		return err
+		return err, true
 	}
 
+	// The account id may be different from the application key id so we're getting the account id from the returned
+	// json object here, which is needed by the b2_list_buckets call.
+	client.AccountID = output.AccountID
+
 	client.AuthorizationToken = output.AuthorizationToken
 	client.APIURL = output.APIURL
-	client.DownloadURL = output.DownloadURL
+	if client.DownloadURL == "" {
+		client.DownloadURL = output.DownloadURL
+	}
+	LOG_INFO("BACKBLAZE_URL", "download URL is: %s", client.DownloadURL)
+	client.IsAuthorized = true
 
-	return nil
+	client.LastAuthorizationTime = time.Now().Unix()
+
+	return nil, true
 }
 
 type ListBucketOutput struct {
-	AccoundID  string
+	AccountID  string
 	BucketID   string
 	BucketName string
 	BucketType string
@@ -243,10 +348,11 @@ func (client *B2Client) FindBucket(bucketName string) (err error) {
 
 	input := make(map[string]string)
 	input["accountId"] = client.AccountID
+	input["bucketName"] = bucketName
 
-	url := client.APIURL + "/b2api/v1/b2_list_buckets"
+	url := client.getAPIURL() + "/b2api/v1/b2_list_buckets"
 
-	readCloser, _, _, err := client.call(url, http.MethodPost, nil, input)
+	readCloser, _, _, err := client.call(0, url, http.MethodPost, nil, input)
 	if err != nil {
 		return err
 	}
@@ -288,7 +394,7 @@ type B2ListFileNamesOutput struct {
 	NextFileId   string
 }
 
-func (client *B2Client) ListFileNames(startFileName string, singleFile bool, includeVersions bool) (files []*B2Entry, err error) {
+func (client *B2Client) ListFileNames(threadIndex int, startFileName string, singleFile bool, includeVersions bool) (files []*B2Entry, err error) {
 
 	maxFileCount := 1000
 	if singleFile {
@@ -306,20 +412,21 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 
 	input := make(map[string]interface{})
 	input["bucketId"] = client.BucketID
-	input["startFileName"] = startFileName
+	input["startFileName"] = client.StorageDir + startFileName
 	input["maxFileCount"] = maxFileCount
+	input["prefix"] = client.StorageDir
 
 	for {
-		url := client.APIURL + "/b2api/v1/b2_list_file_names"
+		apiURL := client.getAPIURL() + "/b2api/v1/b2_list_file_names"
 		requestHeaders := map[string]string{}
 		requestMethod := http.MethodPost
 		var requestInput interface{}
 		requestInput = input
 		if includeVersions {
-			url = client.APIURL + "/b2api/v1/b2_list_file_versions"
+			apiURL = client.getAPIURL() + "/b2api/v1/b2_list_file_versions"
 		} else if singleFile {
 			// handle a single file with no versions as a special case to download the last byte of the file
-			url = client.DownloadURL + "/file/" + client.BucketName + "/" + startFileName
+			apiURL = client.getDownloadURL() + "/file/" + client.BucketName + "/" + B2Escape(client.StorageDir + startFileName)
 			// requesting byte -1 works for empty files where 0-0 fails with a 416 error
 			requestHeaders["Range"] = "bytes=-1"
 			// HEAD request
@@ -329,7 +436,7 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 		var readCloser io.ReadCloser
 		var responseHeader http.Header
 		var err error
-		readCloser, responseHeader, _, err = client.call(url, requestMethod, requestHeaders, requestInput)
+		readCloser, responseHeader, _, err = client.call(threadIndex, apiURL, requestMethod, requestHeaders, requestInput)
 		if err != nil {
 			return nil, err
 		}
@@ -342,7 +449,7 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 
 		if singleFile && !includeVersions {
 			if responseHeader == nil {
-				LOG_DEBUG("BACKBLAZE_LIST", "b2_download_file_by_name did not return headers")
+				LOG_DEBUG("BACKBLAZE_LIST", "%s did not return headers", apiURL)
 				return []*B2Entry{}, nil
 			}
 			requiredHeaders := []string{
@@ -356,11 +463,17 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 				}
 			}
 			if len(missingKeys) > 0 {
-				return nil, fmt.Errorf("b2_download_file_by_name missing headers: %s", missingKeys)
+				return nil, fmt.Errorf("%s missing headers: %s", apiURL, missingKeys)
 			}
 			// construct the B2Entry from the response headers of the download request
 			fileID := responseHeader.Get("x-bz-file-id")
 			fileName := responseHeader.Get("x-bz-file-name")
+			unescapedFileName, err := url.QueryUnescape(fileName)
+			if err == nil {
+				fileName = unescapedFileName
+			} else {
+				LOG_WARN("BACKBLAZE_UNESCAPE", "Failed to unescape the file name %s", fileName)
+			}
 			fileAction := "upload"
 			// byte range that is returned: "bytes #-#/#
 			rangeString := responseHeader.Get("Content-Range")
@@ -373,14 +486,14 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 				// this should only execute if the requested file is empty and the range request didn't result in a Content-Range header
 				fileSize, _ = strconv.ParseInt(lengthString, 0, 64)
 				if fileSize != 0 {
-					return nil, fmt.Errorf("b2_download_file_by_name returned non-zero file length")
+					return nil, fmt.Errorf("%s returned non-zero file length", apiURL)
 				}
 			} else {
-				return nil, fmt.Errorf("could not parse b2_download_file_by_name headers")
+				return nil, fmt.Errorf("could not parse headers returned by %s", apiURL)
 			}
 			fileUploadTimestamp, _ := strconv.ParseInt(responseHeader.Get("X-Bz-Upload-Timestamp"), 0, 64)
 
-			return []*B2Entry{&B2Entry{fileID, fileName, fileAction, fileSize, fileUploadTimestamp}}, nil
+			return []*B2Entry{{fileID, fileName[len(client.StorageDir):], fileAction, fileSize, fileUploadTimestamp}}, nil
 		}
 
 		if err = json.NewDecoder(readCloser).Decode(&output); err != nil {
@@ -389,31 +502,27 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 
 		ioutil.ReadAll(readCloser)
 
-		if startFileName == "" {
-			files = append(files, output.Files...)
-		} else {
-			for _, file := range output.Files {
-				if singleFile {
-					if file.FileName == startFileName {
-						files = append(files, file)
-						if !includeVersions {
-							output.NextFileName = ""
-							break
-						}
-					} else {
+		for _, file := range output.Files {
+			file.FileName = file.FileName[len(client.StorageDir):]
+			if singleFile {
+				if file.FileName == startFileName {
+					files = append(files, file)
+					if !includeVersions {
 						output.NextFileName = ""
 						break
 					}
 				} else {
-					if strings.HasPrefix(file.FileName, startFileName) {
-						files = append(files, file)
-					} else {
-						output.NextFileName = ""
-						break
-					}
+					output.NextFileName = ""
+					break
+				}
+			} else {
+				if strings.HasPrefix(file.FileName, startFileName) {
+					files = append(files, file)
+				} else {
+					output.NextFileName = ""
+					break
 				}
 			}
-
 		}
 
 		if len(output.NextFileName) == 0 {
@@ -429,14 +538,14 @@ func (client *B2Client) ListFileNames(startFileName string, singleFile bool, inc
 	return files, nil
 }
 
-func (client *B2Client) DeleteFile(fileName string, fileID string) (err error) {
+func (client *B2Client) DeleteFile(threadIndex int, fileName string, fileID string) (err error) {
 
 	input := make(map[string]string)
-	input["fileName"] = fileName
+	input["fileName"] = client.StorageDir + fileName
 	input["fileId"] = fileID
 
-	url := client.APIURL + "/b2api/v1/b2_delete_file_version"
-	readCloser, _, _, err := client.call(url, http.MethodPost, make(map[string]string), input)
+	url := client.getAPIURL() + "/b2api/v1/b2_delete_file_version"
+	readCloser, _, _, err := client.call(threadIndex, url, http.MethodPost, make(map[string]string), input)
 	if err != nil {
 		return err
 	}
@@ -449,14 +558,14 @@ type B2HideFileOutput struct {
 	FileID string
 }
 
-func (client *B2Client) HideFile(fileName string) (fileID string, err error) {
+func (client *B2Client) HideFile(threadIndex int, fileName string) (fileID string, err error) {
 
 	input := make(map[string]string)
 	input["bucketId"] = client.BucketID
-	input["fileName"] = fileName
+	input["fileName"] = client.StorageDir + fileName
 
-	url := client.APIURL + "/b2api/v1/b2_hide_file"
-	readCloser, _, _, err := client.call(url, http.MethodPost, make(map[string]string), input)
+	url := client.getAPIURL() + "/b2api/v1/b2_hide_file"
+	readCloser, _, _, err := client.call(threadIndex, url, http.MethodPost, make(map[string]string), input)
 	if err != nil {
 		return "", err
 	}
@@ -473,11 +582,11 @@ func (client *B2Client) HideFile(fileName string) (fileID string, err error) {
 	return output.FileID, nil
 }
 
-func (client *B2Client) DownloadFile(filePath string) (io.ReadCloser, int64, error) {
+func (client *B2Client) DownloadFile(threadIndex int, filePath string) (io.ReadCloser, int64, error) {
 
-	url := client.DownloadURL + "/file/" + client.BucketName + "/" + filePath
+	url := client.getDownloadURL() + "/file/" + client.BucketName + "/" + B2Escape(client.StorageDir + filePath)
 
-	readCloser, _, len, err := client.call(url, http.MethodGet, make(map[string]string), 0)
+	readCloser, _, len, err := client.call(threadIndex, url, http.MethodGet, make(map[string]string), 0)
 	return readCloser, len, err
 }
 
@@ -487,12 +596,12 @@ type B2GetUploadArgumentOutput struct {
 	AuthorizationToken string
 }
 
-func (client *B2Client) getUploadURL() error {
+func (client *B2Client) getUploadURL(threadIndex int) error {
 	input := make(map[string]string)
 	input["bucketId"] = client.BucketID
 
-	url := client.APIURL + "/b2api/v1/b2_get_upload_url"
-	readCloser, _, _, err := client.call(url, http.MethodPost, make(map[string]string), input)
+	url := client.getAPIURL() + "/b2api/v1/b2_get_upload_url"
+	readCloser, _, _, err := client.call(threadIndex, url, http.MethodPost, make(map[string]string), input)
 	if err != nil {
 		return err
 	}
@@ -505,96 +614,29 @@ func (client *B2Client) getUploadURL() error {
 		return err
 	}
 
-	client.UploadURL = output.UploadURL
-	client.UploadToken = output.AuthorizationToken
+	client.UploadURLs[threadIndex] = output.UploadURL
+	client.UploadTokens[threadIndex] = output.AuthorizationToken
 
 	return nil
 }
 
-func (client *B2Client) UploadFile(filePath string, content []byte, rateLimit int) (err error) {
+func (client *B2Client) UploadFile(threadIndex int, filePath string, content []byte, rateLimit int) (err error) {
 
 	hasher := sha1.New()
 	hasher.Write(content)
 	hash := hex.EncodeToString(hasher.Sum(nil))
 
 	headers := make(map[string]string)
-	headers["X-Bz-File-Name"] = filePath
+	headers["X-Bz-File-Name"] = B2Escape(client.StorageDir + filePath)
+	headers["Content-Length"] = fmt.Sprintf("%d", len(content))
 	headers["Content-Type"] = "application/octet-stream"
 	headers["X-Bz-Content-Sha1"] = hash
 
-	var response *http.Response
-
-	backoff := 0
-	for i := 0; i < 8; i++ {
-
-		if client.UploadURL == "" || client.UploadToken == "" {
-			err = client.getUploadURL()
-			if err != nil {
-				return err
-			}
-		}
-
-		request, err := http.NewRequest("POST", client.UploadURL, CreateRateLimitedReader(content, rateLimit))
-		if err != nil {
-			return err
-		}
-		request.ContentLength = int64(len(content))
-
-		request.Header.Set("Authorization", client.UploadToken)
-		request.Header.Set("X-Bz-File-Name", filePath)
-		request.Header.Set("Content-Type", "application/octet-stream")
-		request.Header.Set("X-Bz-Content-Sha1", hash)
-
-		for key, value := range headers {
-			request.Header.Set(key, value)
-		}
-
-		if client.TestMode {
-			r := rand.Float32()
-			if r < 0.8 {
-				request.Header.Set("X-Bz-Test-Mode", "fail_some_uploads")
-			} else if r < 0.9 {
-				request.Header.Set("X-Bz-Test-Mode", "expire_some_account_authorization_tokens")
-			} else {
-				request.Header.Set("X-Bz-Test-Mode", "force_cap_exceeded")
-			}
-		}
-
-		response, err = client.HTTPClient.Do(request)
-		if err != nil {
-			LOG_DEBUG("BACKBLAZE_UPLOAD", "URL request '%s' returned an error: %v", client.UploadURL, err)
-			backoff = client.retry(backoff, response)
-			client.UploadURL = ""
-			client.UploadToken = ""
-			continue
-		}
-
-		io.Copy(ioutil.Discard, response.Body)
-		response.Body.Close()
-
-		if response.StatusCode < 300 {
-			return nil
-		}
-
-		LOG_DEBUG("BACKBLAZE_UPLOAD", "URL request '%s' returned status code %d", client.UploadURL, response.StatusCode)
-
-		if response.StatusCode == 401 {
-			LOG_INFO("BACKBLAZE_UPLOAD", "Re-authorization required")
-			client.UploadURL = ""
-			client.UploadToken = ""
-			continue
-		} else if response.StatusCode == 403 {
-			if !client.TestMode {
-				return fmt.Errorf("B2 cap exceeded")
-			}
-			continue
-		} else {
-			LOG_INFO("BACKBLAZE_UPLOAD", "URL request '%s' returned status code %d", client.UploadURL, response.StatusCode)
-			backoff = client.retry(backoff, response)
-			client.UploadURL = ""
-			client.UploadToken = ""
-		}
+	readCloser, _, _, err := client.call(threadIndex, "", http.MethodPost, headers, CreateRateLimitedReader(content, rateLimit))
+	if err != nil {
+		return err
 	}
 
-	return fmt.Errorf("Maximum backoff reached")
+	readCloser.Close()
+	return nil
 }

src/duplicacy_b2client_test.go

@@ -37,7 +37,7 @@ func createB2ClientForTest(t *testing.T) (*B2Client, string) {
 		return nil, ""
 	}
 
-	return NewB2Client(b2["account"], b2["key"]), b2["bucket"]
+	return NewB2Client(b2["account"], b2["key"], "", b2["directory"], 1), b2["bucket"]
 
 }
 
@@ -50,7 +50,7 @@ func TestB2Client(t *testing.T) {
 
 	b2Client.TestMode = true
 
-	err := b2Client.AuthorizeAccount()
+	err, _ := b2Client.AuthorizeAccount(0)
 	if err != nil {
 		t.Errorf("Failed to authorize the b2 account: %v", err)
 		return
@@ -64,14 +64,14 @@ func TestB2Client(t *testing.T) {
 
 	testDirectory := "b2client_test/"
 
-	files, err := b2Client.ListFileNames(testDirectory, false, false)
+	files, err := b2Client.ListFileNames(0, testDirectory, false, false)
 	if err != nil {
 		t.Errorf("Failed to list files: %v", err)
 		return
 	}
 
 	for _, file := range files {
-		err = b2Client.DeleteFile(file.FileName, file.FileID)
+		err = b2Client.DeleteFile(0, file.FileName, file.FileID)
 		if err != nil {
 			t.Errorf("Failed to delete file '%s': %v", file.FileName, err)
 		}
@@ -90,14 +90,14 @@ func TestB2Client(t *testing.T) {
 		hash := sha256.Sum256(content)
 		name := hex.EncodeToString(hash[:])
 
-		err = b2Client.UploadFile(testDirectory+name, content, 100)
+		err = b2Client.UploadFile(0, testDirectory+name, content, 100)
 		if err != nil {
 			t.Errorf("Error uploading file '%s': %v", name, err)
 			return
 		}
 	}
 
-	files, err = b2Client.ListFileNames(testDirectory, false, false)
+	files, err = b2Client.ListFileNames(0, testDirectory, false, false)
 	if err != nil {
 		t.Errorf("Failed to list files: %v", err)
 		return
@@ -105,7 +105,7 @@ func TestB2Client(t *testing.T) {
 
 	for _, file := range files {
 
-		readCloser, _, err := b2Client.DownloadFile(file.FileName)
+		readCloser, _, err := b2Client.DownloadFile(0, file.FileName)
 		if err != nil {
 			t.Errorf("Error downloading file '%s': %v", file.FileName, err)
 			return
@@ -125,7 +125,7 @@ func TestB2Client(t *testing.T) {
 	}
 
 	for _, file := range files {
-		err = b2Client.DeleteFile(file.FileName, file.FileID)
+		err = b2Client.DeleteFile(0, file.FileName, file.FileID)
 		if err != nil {
 			t.Errorf("Failed to delete file '%s': %v", file.FileName, err)
 		}

src/duplicacy_b2storage.go

@@ -11,32 +11,26 @@ import (
 type B2Storage struct {
 	StorageBase
 
-	clients []*B2Client
+	client *B2Client
 }
 
 // CreateB2Storage creates a B2 storage object.
-func CreateB2Storage(accountID string, applicationKey string, bucket string, threads int) (storage *B2Storage, err error) {
+func CreateB2Storage(accountID string, applicationKey string, downloadURL string, bucket string, storageDir string, threads int) (storage *B2Storage, err error) {
 
-	var clients []*B2Client
+	client := NewB2Client(accountID, applicationKey, downloadURL, storageDir, threads)
 
-	for i := 0; i < threads; i++ {
-		client := NewB2Client(accountID, applicationKey)
+	err, _ = client.AuthorizeAccount(0)
+	if err != nil {
+		return nil, err
+	}
 
-		err = client.AuthorizeAccount()
-		if err != nil {
-			return nil, err
-		}
-
-		err = client.FindBucket(bucket)
-		if err != nil {
-			return nil, err
-		}
-
-		clients = append(clients, client)
+	err = client.FindBucket(bucket)
+	if err != nil {
+		return nil, err
 	}
 
 	storage = &B2Storage{
-		clients: clients,
+		client: client,
 	}
 
 	storage.DerivedStorage = storage
@@ -56,7 +50,7 @@ func (storage *B2Storage) ListFiles(threadIndex int, dir string) (files []string
 		includeVersions = true
 	}
 
-	entries, err := storage.clients[threadIndex].ListFileNames(dir, false, includeVersions)
+	entries, err := storage.client.ListFileNames(threadIndex, dir, false, includeVersions)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -71,7 +65,7 @@ func (storage *B2Storage) ListFiles(threadIndex int, dir string) (files []string
 			subDirs[subDir+"/"] = true
 		}
 
-		for subDir, _ := range subDirs {
+		for subDir := range subDirs {
 			files = append(files, subDir)
 		}
 	} else if dir == "chunks" {
@@ -102,7 +96,7 @@ func (storage *B2Storage) DeleteFile(threadIndex int, filePath string) (err erro
 
 	if strings.HasSuffix(filePath, ".fsl") {
 		filePath = filePath[:len(filePath)-len(".fsl")]
-		entries, err := storage.clients[threadIndex].ListFileNames(filePath, true, true)
+		entries, err := storage.client.ListFileNames(threadIndex, filePath, true, true)
 		if err != nil {
 			return err
 		}
@@ -116,7 +110,7 @@ func (storage *B2Storage) DeleteFile(threadIndex int, filePath string) (err erro
 
 			toBeDeleted = true
 
-			err = storage.clients[threadIndex].DeleteFile(filePath, entry.FileID)
+			err = storage.client.DeleteFile(threadIndex, filePath, entry.FileID)
 			if err != nil {
 				return err
 			}
@@ -125,7 +119,7 @@ func (storage *B2Storage) DeleteFile(threadIndex int, filePath string) (err erro
 		return nil
 
 	} else {
-		entries, err := storage.clients[threadIndex].ListFileNames(filePath, true, false)
+		entries, err := storage.client.ListFileNames(threadIndex, filePath, true, false)
 		if err != nil {
 			return err
 		}
@@ -133,7 +127,7 @@ func (storage *B2Storage) DeleteFile(threadIndex int, filePath string) (err erro
 		if len(entries) == 0 {
 			return nil
 		}
-		return storage.clients[threadIndex].DeleteFile(filePath, entries[0].FileID)
+		return storage.client.DeleteFile(threadIndex, filePath, entries[0].FileID)
 	}
 }
 
@@ -160,10 +154,10 @@ func (storage *B2Storage) MoveFile(threadIndex int, from string, to string) (err
 	}
 
 	if filePath == from {
-		_, err = storage.clients[threadIndex].HideFile(from)
+		_, err = storage.client.HideFile(threadIndex, from)
 		return err
 	} else {
-		entries, err := storage.clients[threadIndex].ListFileNames(filePath, true, true)
+		entries, err := storage.client.ListFileNames(threadIndex, filePath, true, true)
 		if err != nil {
 			return err
 		}
@@ -171,7 +165,7 @@ func (storage *B2Storage) MoveFile(threadIndex int, from string, to string) (err
 			return nil
 		}
 
-		return storage.clients[threadIndex].DeleteFile(filePath, entries[0].FileID)
+		return storage.client.DeleteFile(threadIndex, filePath, entries[0].FileID)
 	}
 }
 
@@ -188,7 +182,7 @@ func (storage *B2Storage) GetFileInfo(threadIndex int, filePath string) (exist b
 		filePath = filePath[:len(filePath)-len(".fsl")]
 	}
 
-	entries, err := storage.clients[threadIndex].ListFileNames(filePath, true, isFossil)
+	entries, err := storage.client.ListFileNames(threadIndex, filePath, true, isFossil)
 	if err != nil {
 		return false, false, 0, err
 	}
@@ -210,22 +204,20 @@ func (storage *B2Storage) GetFileInfo(threadIndex int, filePath string) (exist b
 // DownloadFile reads the file at 'filePath' into the chunk.
 func (storage *B2Storage) DownloadFile(threadIndex int, filePath string, chunk *Chunk) (err error) {
 
-	filePath = strings.Replace(filePath, " ", "%20", -1)
-	readCloser, _, err := storage.clients[threadIndex].DownloadFile(filePath)
+	readCloser, _, err := storage.client.DownloadFile(threadIndex, filePath)
 	if err != nil {
 		return err
 	}
 
 	defer readCloser.Close()
 
-	_, err = RateLimitedCopy(chunk, readCloser, storage.DownloadRateLimit/len(storage.clients))
+	_, err = RateLimitedCopy(chunk, readCloser, storage.DownloadRateLimit/storage.client.Threads)
 	return err
 }
 
 // UploadFile writes 'content' to the file at 'filePath'.
 func (storage *B2Storage) UploadFile(threadIndex int, filePath string, content []byte) (err error) {
-	filePath = strings.Replace(filePath, " ", "%20", -1)
-	return storage.clients[threadIndex].UploadFile(filePath, content, storage.UploadRateLimit/len(storage.clients))
+	return storage.client.UploadFile(threadIndex, filePath, content, storage.UploadRateLimit/storage.client.Threads)
 }
 
 // If a local snapshot cache is needed for the storage to avoid downloading/uploading chunks too often when
@@ -243,7 +235,5 @@ func (storage *B2Storage) IsFastListing() bool { return true }
 
 // Enable the test mode.
 func (storage *B2Storage) EnableTestMode() {
-	for _, client := range storage.clients {
-		client.TestMode = true
-	}
+	storage.client.TestMode = true
 }

src/duplicacy_backupmanager.go

@@ -33,6 +33,9 @@ type BackupManager struct {
 	snapshotCache   *FileStorage     // for copies of chunks needed by snapshots
 
 	config *Config // contains a number of options
+
+	nobackupFile string // don't backup directory when this file name is found
+	filtersFile string  // the path to the filters file
 }
 
 func (manager *BackupManager) SetDryRun(dryRun bool) {
@@ -42,7 +45,7 @@ func (manager *BackupManager) SetDryRun(dryRun bool) {
 // CreateBackupManager creates a backup manager using the specified 'storage'.  'snapshotID' is a unique id to
 // identify snapshots created for this repository.  'top' is the top directory of the repository.  'password' is the
 // master key which can be nil if encryption is not enabled.
-func CreateBackupManager(snapshotID string, storage Storage, top string, password string) *BackupManager {
+func CreateBackupManager(snapshotID string, storage Storage, top string, password string, nobackupFile string, filtersFile string) *BackupManager {
 
 	config, _, err := DownloadConfig(storage, password)
 	if err != nil {
@@ -63,6 +66,9 @@ func CreateBackupManager(snapshotID string, storage Storage, top string, passwor
 		SnapshotManager: snapshotManager,
 
 		config: config,
+
+		nobackupFile: nobackupFile,
+		filtersFile: filtersFile,
 	}
 
 	if IsDebugging() {
@@ -72,6 +78,11 @@ func CreateBackupManager(snapshotID string, storage Storage, top string, passwor
 	return backupManager
 }
 
+// loadRSAPrivateKey loads the specifed private key file for decrypting file chunks
+func (manager *BackupManager) LoadRSAPrivateKey(keyFile string, passphrase string) {
+	manager.config.loadRSAPrivateKey(keyFile, passphrase)
+}
+
 // SetupSnapshotCache creates the snapshot cache, which is merely a local storage under the default .duplicacy
 // directory
 func (manager *BackupManager) SetupSnapshotCache(storageName string) bool {
@@ -99,6 +110,7 @@ func (manager *BackupManager) SetupSnapshotCache(storageName string) bool {
 	return true
 }
 
+
 // setEntryContent sets the 4 content pointers for each entry in 'entries'.  'offset' indicates the value
 // to be added to the StartChunk and EndChunk points, used when intending to append 'entries' to the
 // original unchanged entry list.
@@ -159,7 +171,7 @@ func setEntryContent(entries []*Entry, chunkLengths []int, offset int) {
 // unmodified files with last backup).  Otherwise (or if this is the first backup), the entire repository will
 // be scanned to create the snapshot.  'tag' is the tag assigned to the new snapshot.
 func (manager *BackupManager) Backup(top string, quickMode bool, threads int, tag string,
-	showStatistics bool, shadowCopy bool, shadowCopyTimeout int) bool {
+	showStatistics bool, shadowCopy bool, shadowCopyTimeout int, enumOnly bool) bool {
 
 	var err error
 	top, err = filepath.Abs(top)
@@ -172,6 +184,15 @@ func (manager *BackupManager) Backup(top string, quickMode bool, threads int, ta
 
 	LOG_DEBUG("BACKUP_PARAMETERS", "top: %s, quick: %t, tag: %s", top, quickMode, tag)
 
+	if manager.config.DataShards != 0 && manager.config.ParityShards != 0 {
+		LOG_INFO("BACKUP_ERASURECODING", "Erasure coding is enabled with %d data shards and %d parity shards",
+		         manager.config.DataShards, manager.config.ParityShards)
+	}
+
+	if manager.config.rsaPublicKey != nil && len(manager.config.FileKey) > 0 {
+		LOG_INFO("BACKUP_KEY", "RSA encryption is enabled")
+	}
+
 	remoteSnapshot := manager.SnapshotManager.downloadLatestSnapshot(manager.snapshotID)
 	if remoteSnapshot == nil {
 		remoteSnapshot = CreateEmptySnapshot(manager.snapshotID)
@@ -184,12 +205,22 @@ func (manager *BackupManager) Backup(top string, quickMode bool, threads int, ta
 	defer DeleteShadowCopy()
 
 	LOG_INFO("BACKUP_INDEXING", "Indexing %s", top)
-	localSnapshot, skippedDirectories, skippedFiles, err := CreateSnapshotFromDirectory(manager.snapshotID, shadowTop)
+	localSnapshot, skippedDirectories, skippedFiles, err := CreateSnapshotFromDirectory(manager.snapshotID, shadowTop,
+		                                                                                manager.nobackupFile, manager.filtersFile)
 	if err != nil {
 		LOG_ERROR("SNAPSHOT_LIST", "Failed to list the directory %s: %v", top, err)
 		return false
 	}
 
+	if enumOnly {
+		return true
+	}
+
+	if len(localSnapshot.Files) == 0 {
+		LOG_ERROR("SNAPSHOT_EMPTY", "No files under the repository to be backed up")
+		return false
+	}
+
 	// This cache contains all chunks referenced by last snasphot. Any other chunks will lead to a call to
 	// UploadChunk.
 	chunkCache := make(map[string]bool)
@@ -464,7 +495,7 @@ func (manager *BackupManager) Backup(top string, quickMode bool, threads int, ta
 
 			uploadedModifiedFileSize := atomic.AddInt64(&uploadedModifiedFileSize, int64(chunkSize))
 
-			if IsTracing() || showStatistics {
+			if (IsTracing() || showStatistics) && totalModifiedFileSize > 0 {
 				now := time.Now().Unix()
 				if now <= startUploadingTime {
 					now = startUploadingTime + 1
@@ -494,6 +525,11 @@ func (manager *BackupManager) Backup(top string, quickMode bool, threads int, ta
 				chunkID := chunk.GetID()
 				chunkSize := chunk.GetLength()
 
+				if chunkSize == 0 {
+					LOG_DEBUG("CHUNK_EMPTY", "Ignored chunk %s of size 0", chunkID)
+					return
+				}
+
 				chunkIndex++
 
 				_, found := chunkCache[chunkID]
@@ -752,7 +788,8 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 	remoteSnapshot := manager.SnapshotManager.DownloadSnapshot(manager.snapshotID, revision)
 	manager.SnapshotManager.DownloadSnapshotContents(remoteSnapshot, patterns, true)
 
-	localSnapshot, _, _, err := CreateSnapshotFromDirectory(manager.snapshotID, top)
+	localSnapshot, _, _, err := CreateSnapshotFromDirectory(manager.snapshotID, top, manager.nobackupFile,
+		                                                    manager.filtersFile)
 	if err != nil {
 		LOG_ERROR("SNAPSHOT_LIST", "Failed to list the repository: %v", err)
 		return false
@@ -767,10 +804,7 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 		for _, file := range remoteSnapshot.Files {
 
 			if MatchPath(file.Path, patterns) {
-				LOG_TRACE("RESTORE_INCLUDE", "Include %s", file.Path)
 				includedFiles = append(includedFiles, file)
-			} else {
-				LOG_TRACE("RESTORE_EXCLUDE", "Exclude %s", file.Path)
 			}
 		}
 
@@ -802,6 +836,7 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 				if compare == 0 {
 					i++
 					if quickMode && local.IsSameAs(entry) {
+						LOG_TRACE("RESTORE_SKIP", "File %s unchanged (by size and timestamp)", local.Path)
 						skipped = true
 					}
 				}
@@ -820,6 +855,7 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 				if stat.Mode()&os.ModeSymlink != 0 {
 					isRegular, link, err := Readlink(fullPath)
 					if err == nil && link == entry.Link && !isRegular {
+						entry.RestoreMetadata(fullPath, nil, setOwner)
 						continue
 					}
 				}
@@ -832,12 +868,13 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 				LOG_ERROR("RESTORE_SYMLINK", "Can't create symlink %s: %v", entry.Path, err)
 				return false
 			}
+			entry.RestoreMetadata(fullPath, nil, setOwner)
 			LOG_TRACE("DOWNLOAD_DONE", "Symlink %s updated", entry.Path)
 		} else if entry.IsDir() {
 			stat, err := os.Stat(fullPath)
 
 			if err == nil && !stat.IsDir() {
-				LOG_ERROR("RESTORE_NOTDIR", "The path %s is not a directory: %v", fullPath, err)
+				LOG_ERROR("RESTORE_NOTDIR", "The path %s is not a directory", fullPath)
 				return false
 			}
 
@@ -891,7 +928,8 @@ func (manager *BackupManager) Restore(top string, revision int, inPlace bool, qu
 				continue
 			}
 		} else {
-			err = os.MkdirAll(path.Dir(fullPath), 0744)
+			parent, _ := SplitDir(fullPath)
+			err = os.MkdirAll(parent, 0744)
 			if err != nil {
 				LOG_ERROR("DOWNLOAD_MKDIR", "Failed to create directory: %v", err)
 			}
@@ -974,12 +1012,12 @@ type fileEncoder struct {
 	buffer         *bytes.Buffer
 }
 
-// Read reads data from the embeded buffer
+// Read reads data from the embedded buffer
 func (encoder fileEncoder) Read(data []byte) (n int, err error) {
 	return encoder.buffer.Read(data)
 }
 
-// NextFile switchs to the next file and generates its json description in the buffer.  It also takes care of
+// NextFile switches to the next file and generates its json description in the buffer.  It also takes care of
 // the ending ']' and the commas between files.
 func (encoder *fileEncoder) NextFile() (io.Reader, bool) {
 	if encoder.currentIndex == len(encoder.files) {
@@ -1119,7 +1157,7 @@ func (manager *BackupManager) UploadSnapshot(chunkMaker *ChunkMaker, uploader *C
 }
 
 // Restore downloads a file from the storage.  If 'inPlace' is false, the download file is saved first to a temporary
-// file under the .duplicacy directory and then replaces the existing one.  Otherwise, the exising file will be
+// file under the .duplicacy directory and then replaces the existing one.  Otherwise, the existing file will be
 // overwritten directly.
 func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chunkMaker *ChunkMaker, entry *Entry, top string, inPlace bool, overwrite bool,
 	showStatistics bool, totalFileSize int64, downloadedFileSize int64, startTime int64) bool {
@@ -1155,6 +1193,9 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 	lengthMap := make(map[string]int)
 	var offset int64
 
+	// If the file is newly created (needed by sparse file optimization)
+	isNewFile := false
+
 	existingFile, err = os.Open(fullPath)
 	if err != nil {
 		if os.IsNotExist(err) {
@@ -1189,6 +1230,7 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 					LOG_ERROR("DOWNLOAD_OPEN", "Can't reopen the initial file just created: %v", err)
 					return false
 				}
+				isNewFile = true
 			}
 		} else {
 			LOG_TRACE("DOWNLOAD_OPEN", "Can't open the existing file: %v", err)
@@ -1201,6 +1243,9 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 		}
 	}
 
+	// The key in this map is the number of zeroes.  The value is the corresponding hash.
+	knownHashes := make(map[int]string)
+
 	fileHash := ""
 	if existingFile != nil {
 
@@ -1210,6 +1255,7 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 			fileHasher := manager.config.NewFileHasher()
 			buffer := make([]byte, 64*1024)
 			err = nil
+			isSkipped := false
 			// We set to read one more byte so the file hash will be different if the file to be restored is a
 			// truncated portion of the existing file
 			for i := entry.StartChunk; i <= entry.EndChunk+1; i++ {
@@ -1225,6 +1271,28 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 					chunkSize = 1 // the size of extra chunk beyond EndChunk
 				}
 				count := 0
+
+				if isNewFile {
+					if hash, found := knownHashes[chunkSize]; found {
+						// We have read the same number of zeros before, so we just retrieve the hash from the map
+						existingChunks = append(existingChunks, hash)
+						existingLengths = append(existingLengths, chunkSize)
+						offsetMap[hash] = offset
+						lengthMap[hash] = chunkSize
+						offset += int64(chunkSize)
+						isSkipped = true
+						continue
+					}
+				}
+
+				if isSkipped {
+					_, err := existingFile.Seek(offset, 0)
+					if err != nil {
+						LOG_ERROR("DOWNLOAD_SEEK", "Failed to seek to offset %d: %v", offset, err)
+					}
+					isSkipped = false
+				}
+
 				for count < chunkSize {
 					n := chunkSize - count
 					if n > cap(buffer) {
@@ -1251,12 +1319,16 @@ func (manager *BackupManager) RestoreFile(chunkDownloader *ChunkDownloader, chun
 					offsetMap[hash] = offset
 					lengthMap[hash] = chunkSize
 					offset += int64(chunkSize)
+					if isNewFile {
+						knownHashes[chunkSize] = hash
+					}
 				}
 
 				if err == io.EOF {
 					break
 				}
 			}
+
 			fileHash = hex.EncodeToString(fileHasher.Sum(nil))
 		} else {
 			// If it is not inplace, we want to reuse any chunks in the existing file regardless their offets, so
@@ -1486,10 +1558,19 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 	revisionsToBeCopied []int, threads int) bool {
 
 	if !manager.config.IsCompatiableWith(otherManager.config) {
-		LOG_ERROR("CONFIG_INCOMPATIABLE", "Two storages are not compatiable for the copy operation")
+		LOG_ERROR("CONFIG_INCOMPATIBLE", "Two storages are not compatible for the copy operation")
 		return false
 	}
 
+	if otherManager.config.DataShards != 0 && otherManager.config.ParityShards != 0 {
+		LOG_INFO("BACKUP_ERASURECODING", "Erasure coding is enabled for the destination storage with %d data shards and %d parity shards",
+		         otherManager.config.DataShards, otherManager.config.ParityShards)
+	}
+
+	if otherManager.config.rsaPublicKey != nil && len(otherManager.config.FileKey) > 0 {
+		LOG_INFO("BACKUP_KEY", "RSA encryption is enabled for the destination")
+	}
+
 	if snapshotID == "" && len(revisionsToBeCopied) > 0 {
 		LOG_ERROR("SNAPSHOT_ERROR", "You must specify the snapshot id when one or more revisions are specified.")
 		return false
@@ -1569,6 +1650,9 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 		return true
 	}
 
+	// These two maps store hashes of chunks in the source and destination storages, respectively.  Note that
+	// the value of 'chunks' is used to indicated if the chunk is a snapshot chunk, while the value of 'otherChunks' 
+	// is not used.
 	chunks := make(map[string]bool)
 	otherChunks := make(map[string]bool)
 
@@ -1581,21 +1665,15 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 		LOG_TRACE("SNAPSHOT_COPY", "Copying snapshot %s at revision %d", snapshot.ID, snapshot.Revision)
 
 		for _, chunkHash := range snapshot.FileSequence {
-			if _, found := chunks[chunkHash]; !found {
-				chunks[chunkHash] = true
-			}
+			chunks[chunkHash] = true  // The chunk is a snapshot chunk
 		}
 
 		for _, chunkHash := range snapshot.ChunkSequence {
-			if _, found := chunks[chunkHash]; !found {
-				chunks[chunkHash] = true
-			}
+			chunks[chunkHash] = true  // The chunk is a snapshot chunk
 		}
 
 		for _, chunkHash := range snapshot.LengthSequence {
-			if _, found := chunks[chunkHash]; !found {
-				chunks[chunkHash] = true
-			}
+			chunks[chunkHash] = true  // The chunk is a snapshot chunk
 		}
 
 		description := manager.SnapshotManager.DownloadSequence(snapshot.ChunkSequence)
@@ -1608,9 +1686,11 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 
 		for _, chunkHash := range snapshot.ChunkHashes {
 			if _, found := chunks[chunkHash]; !found {
-				chunks[chunkHash] = true
+				chunks[chunkHash] = false  // The chunk is a file chunk
 			}
 		}
+
+		snapshot.ChunkHashes = nil
 	}
 
 	otherChunkFiles, otherChunkSizes := otherManager.SnapshotManager.ListAllFiles(otherManager.storage, "chunks/")
@@ -1632,7 +1712,7 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 	chunksToCopy := 0
 	chunksToSkip := 0
 
-	for chunkHash, _ := range chunks {
+	for chunkHash := range chunks {
 		otherChunkID := otherManager.config.GetChunkIDFromHash(chunkHash)
 		if _, found := otherChunks[otherChunkID]; found {
 			chunksToSkip++
@@ -1662,7 +1742,7 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 	totalSkipped := 0
 	chunkIndex := 0
 
-	for chunkHash, _ := range chunks {
+	for chunkHash, isSnapshot := range chunks {
 		chunkIndex++
 		chunkID := manager.config.GetChunkIDFromHash(chunkHash)
 		newChunkID := otherManager.config.GetChunkIDFromHash(chunkHash)
@@ -1673,6 +1753,7 @@ func (manager *BackupManager) CopySnapshots(otherManager *BackupManager, snapsho
 			newChunk := otherManager.config.GetChunk()
 			newChunk.Reset(true)
 			newChunk.Write(chunk.GetBytes())
+			newChunk.isSnapshot = isSnapshot
 			chunkUploader.StartChunk(newChunk, chunkIndex)
 			totalCopied++
 		} else {

src/duplicacy_backupmanager_test.go

@@ -226,12 +226,20 @@ func TestBackupManager(t *testing.T) {
 	cleanStorage(storage)
 
 	time.Sleep(time.Duration(delay) * time.Second)
+
+	dataShards := 0
+	parityShards := 0
+	if testErasureCoding {
+		dataShards = 5
+		parityShards = 2
+	}
+
 	if testFixedChunkSize {
-		if !ConfigStorage(storage, 16384, 100, 64*1024, 64*1024, 64*1024, password, nil, false) {
+		if !ConfigStorage(storage, 16384, 100, 64*1024, 64*1024, 64*1024, password, nil, false, "", dataShards, parityShards) {
 			t.Errorf("Failed to initialize the storage")
 		}
 	} else {
-		if !ConfigStorage(storage, 16384, 100, 64*1024, 256*1024, 16*1024, password, nil, false) {
+		if !ConfigStorage(storage, 16384, 100, 64*1024, 256*1024, 16*1024, password, nil, false, "", dataShards, parityShards) {
 			t.Errorf("Failed to initialize the storage")
 		}
 	}
@@ -239,15 +247,15 @@ func TestBackupManager(t *testing.T) {
 	time.Sleep(time.Duration(delay) * time.Second)
 
 	SetDuplicacyPreferencePath(testDir + "/repository1/.duplicacy")
-	backupManager := CreateBackupManager("host1", storage, testDir, password)
+	backupManager := CreateBackupManager("host1", storage, testDir, password, "", "")
 	backupManager.SetupSnapshotCache("default")
 
 	SetDuplicacyPreferencePath(testDir + "/repository1/.duplicacy")
-	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, true, threads, "first", false, false, 0)
+	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, true, threads, "first", false, false, 0, false)
 	time.Sleep(time.Duration(delay) * time.Second)
 	SetDuplicacyPreferencePath(testDir + "/repository2/.duplicacy")
-	backupManager.Restore(testDir+"/repository2", threads, /*inPlace=*/false, /*quickMode=*/false, threads, /*overwrite=*/true,
-		/*deleteMode=*/false, /*setowner=*/false, /*showStatistics=*/false, /*patterns=*/ nil)
+	backupManager.Restore(testDir+"/repository2", threads /*inPlace=*/, false /*quickMode=*/, false, threads /*overwrite=*/, true,
+		/*deleteMode=*/ false /*setowner=*/, false /*showStatistics=*/, false /*patterns=*/, nil)
 
 	for _, f := range []string{"file1", "file2", "dir1/file3"} {
 		if _, err := os.Stat(testDir + "/repository2/" + f); os.IsNotExist(err) {
@@ -267,11 +275,11 @@ func TestBackupManager(t *testing.T) {
 	modifyFile(testDir+"/repository1/dir1/file3", 0.3)
 
 	SetDuplicacyPreferencePath(testDir + "/repository1/.duplicacy")
-	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, true, threads, "second", false, false, 0)
+	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, true, threads, "second", false, false, 0, false)
 	time.Sleep(time.Duration(delay) * time.Second)
 	SetDuplicacyPreferencePath(testDir + "/repository2/.duplicacy")
-	backupManager.Restore(testDir+"/repository2", 2, /*inPlace=*/true, /*quickMode=*/true, threads, /*overwrite=*/true,
-		/*deleteMode=*/false, /*setowner=*/false, /*showStatistics=*/false, /*patterns=*/nil)
+	backupManager.Restore(testDir+"/repository2", 2 /*inPlace=*/, true /*quickMode=*/, true, threads /*overwrite=*/, true,
+		/*deleteMode=*/ false /*setowner=*/, false /*showStatistics=*/, false /*patterns=*/, nil)
 
 	for _, f := range []string{"file1", "file2", "dir1/file3"} {
 		hash1 := getFileHash(testDir + "/repository1/" + f)
@@ -287,7 +295,7 @@ func TestBackupManager(t *testing.T) {
 	os.Mkdir(testDir+"/repository1/dir2/dir3", 0700)
 	os.Mkdir(testDir+"/repository1/dir4", 0700)
 	SetDuplicacyPreferencePath(testDir + "/repository1/.duplicacy")
-	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, false, threads, "third", false, false, 0)
+	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, false, threads, "third", false, false, 0, false)
 	time.Sleep(time.Duration(delay) * time.Second)
 
 	// Create some directories and files under repository2 that will be deleted during restore
@@ -298,8 +306,8 @@ func TestBackupManager(t *testing.T) {
 	createRandomFile(testDir+"/repository2/dir5/file5", 100)
 
 	SetDuplicacyPreferencePath(testDir + "/repository2/.duplicacy")
-	backupManager.Restore(testDir+"/repository2", 3, /*inPlace=*/true, /*quickMode=*/false, threads, /*overwrite=*/true,
-		/*deleteMode=*/true, /*setowner=*/false, /*showStatistics=*/false, /*patterns=*/nil)
+	backupManager.Restore(testDir+"/repository2", 3 /*inPlace=*/, true /*quickMode=*/, false, threads /*overwrite=*/, true,
+		/*deleteMode=*/ true /*setowner=*/, false /*showStatistics=*/, false /*patterns=*/, nil)
 
 	for _, f := range []string{"file1", "file2", "dir1/file3"} {
 		hash1 := getFileHash(testDir + "/repository1/" + f)
@@ -325,8 +333,8 @@ func TestBackupManager(t *testing.T) {
 	os.Remove(testDir + "/repository1/file2")
 	os.Remove(testDir + "/repository1/dir1/file3")
 	SetDuplicacyPreferencePath(testDir + "/repository1/.duplicacy")
-	backupManager.Restore(testDir+"/repository1", 3, /*inPlace=*/true, /*quickMode=*/false, threads, /*overwrite=*/true,
-		/*deleteMode=*/false,  /*setowner=*/false, /*showStatistics=*/false, /*patterns=*/[]string{"+file2", "+dir1/file3", "-*"})
+	backupManager.Restore(testDir+"/repository1", 3 /*inPlace=*/, true /*quickMode=*/, false, threads /*overwrite=*/, true,
+		/*deleteMode=*/ false /*setowner=*/, false /*showStatistics=*/, false /*patterns=*/, []string{"+file2", "+dir1/file3", "-*"})
 
 	for _, f := range []string{"file1", "file2", "dir1/file3"} {
 		hash1 := getFileHash(testDir + "/repository1/" + f)
@@ -341,24 +349,24 @@ func TestBackupManager(t *testing.T) {
 		t.Errorf("Expected 3 snapshots but got %d", numberOfSnapshots)
 	}
 	backupManager.SnapshotManager.CheckSnapshots( /*snapshotID*/ "host1" /*revisions*/, []int{1, 2, 3} /*tag*/, "",
-		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*searchFossils*/, false /*resurrect*/, false)
+		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*checkChunks*/, false /*searchFossils*/, false /*resurrect*/, false, 1)
 	backupManager.SnapshotManager.PruneSnapshots("host1", "host1" /*revisions*/, []int{1} /*tags*/, nil /*retentions*/, nil,
-		/*exhaustive*/ false /*exclusive=*/, false /*ignoredIDs*/, nil /*dryRun*/, false /*deleteOnly*/, false /*collectOnly*/, false)
+		/*exhaustive*/ false /*exclusive=*/, false /*ignoredIDs*/, nil /*dryRun*/, false /*deleteOnly*/, false /*collectOnly*/, false, 1)
 	numberOfSnapshots = backupManager.SnapshotManager.ListSnapshots( /*snapshotID*/ "host1" /*revisionsToList*/, nil /*tag*/, "" /*showFiles*/, false /*showChunks*/, false)
 	if numberOfSnapshots != 2 {
 		t.Errorf("Expected 2 snapshots but got %d", numberOfSnapshots)
 	}
 	backupManager.SnapshotManager.CheckSnapshots( /*snapshotID*/ "host1" /*revisions*/, []int{2, 3} /*tag*/, "",
-		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*searchFossils*/, false /*resurrect*/, false)
-	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, false, threads, "fourth", false, false, 0)
+		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*checkChunks*/, false /*searchFossils*/, false /*resurrect*/, false, 1)
+	backupManager.Backup(testDir+"/repository1" /*quickMode=*/, false, threads, "fourth", false, false, 0, false)
 	backupManager.SnapshotManager.PruneSnapshots("host1", "host1" /*revisions*/, nil /*tags*/, nil /*retentions*/, nil,
-		/*exhaustive*/ false /*exclusive=*/, true /*ignoredIDs*/, nil /*dryRun*/, false /*deleteOnly*/, false /*collectOnly*/, false)
+		/*exhaustive*/ false /*exclusive=*/, true /*ignoredIDs*/, nil /*dryRun*/, false /*deleteOnly*/, false /*collectOnly*/, false, 1)
 	numberOfSnapshots = backupManager.SnapshotManager.ListSnapshots( /*snapshotID*/ "host1" /*revisionsToList*/, nil /*tag*/, "" /*showFiles*/, false /*showChunks*/, false)
 	if numberOfSnapshots != 3 {
 		t.Errorf("Expected 3 snapshots but got %d", numberOfSnapshots)
 	}
 	backupManager.SnapshotManager.CheckSnapshots( /*snapshotID*/ "host1" /*revisions*/, []int{2, 3, 4} /*tag*/, "",
-		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*searchFossils*/, false /*resurrect*/, false)
+		/*showStatistics*/ false /*showTabular*/, false /*checkFiles*/, false /*checkChunks*/, false /*searchFossils*/, false /*resurrect*/, false, 1)
 
 	/*buf := make([]byte, 1<<16)
 	  runtime.Stack(buf, true)

src/duplicacy_benchmark.go

@@ -0,0 +1,235 @@
+// Copyright (c) Acrosync LLC. All rights reserved.
+// Free for personal use and commercial trial
+// Commercial use requires per-user licenses available from https://duplicacy.com
+
+package duplicacy
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+func benchmarkSplit(reader *bytes.Reader, fileSize int64, chunkSize int, compression bool, encryption bool, annotation string) {
+
+	config := CreateConfig()
+	config.CompressionLevel = DEFAULT_COMPRESSION_LEVEL
+	config.AverageChunkSize = chunkSize
+	config.MaximumChunkSize = chunkSize * 4
+	config.MinimumChunkSize = chunkSize / 4
+	config.ChunkSeed = []byte("duplicacy")
+
+	config.HashKey = DEFAULT_KEY
+	config.IDKey = DEFAULT_KEY
+
+	maker := CreateChunkMaker(config, false)
+
+	startTime := float64(time.Now().UnixNano()) / 1e9
+	numberOfChunks := 0
+	reader.Seek(0, os.SEEK_SET)
+	maker.ForEachChunk(reader,
+		func(chunk *Chunk, final bool) {
+			if compression {
+				key := ""
+				if encryption {
+					key = "0123456789abcdef0123456789abcdef"
+				}
+				err := chunk.Encrypt([]byte(key), "", false)
+				if err != nil {
+					LOG_ERROR("BENCHMARK_ENCRYPT", "Failed to encrypt the chunk: %v", err)
+				}
+			}
+			config.PutChunk(chunk)
+			numberOfChunks++
+		},
+		func(size int64, hash string) (io.Reader, bool) {
+			return nil, false
+		})
+
+	runningTime := float64(time.Now().UnixNano())/1e9 - startTime
+	speed := int64(float64(fileSize) / runningTime)
+	LOG_INFO("BENCHMARK_SPLIT", "Split %s bytes into %d chunks %s in %.2fs: %s/s", PrettySize(fileSize), numberOfChunks, annotation,
+		runningTime, PrettySize(speed))
+
+	return
+}
+
+func benchmarkRun(threads int, chunkCount int, job func(threadIndex int, chunkIndex int)) {
+	indexChannel := make(chan int, chunkCount)
+	stopChannel := make(chan int, threads)
+	finishChannel := make(chan int, threads)
+
+	// Start the uploading goroutines
+	for i := 0; i < threads; i++ {
+		go func(threadIndex int) {
+			defer CatchLogException()
+			for {
+				select {
+				case chunkIndex := <-indexChannel:
+					job(threadIndex, chunkIndex)
+					finishChannel <- 0
+				case <-stopChannel:
+					return
+				}
+			}
+		}(i)
+	}
+
+	for i := 0; i < chunkCount; i++ {
+		indexChannel <- i
+	}
+
+	for i := 0; i < chunkCount; i++ {
+		<-finishChannel
+	}
+
+	for i := 0; i < threads; i++ {
+		stopChannel <- 0
+	}
+}
+
+func Benchmark(localDirectory string, storage Storage, fileSize int64, chunkSize int, chunkCount int, uploadThreads int, downloadThreads int) bool {
+
+	filename := filepath.Join(localDirectory, "benchmark.dat")
+
+	defer func() {
+		os.Remove(filename)
+	}()
+
+	LOG_INFO("BENCHMARK_GENERATE", "Generating %s byte random data in memory", PrettySize(fileSize))
+	data := make([]byte, fileSize)
+	_, err := rand.Read(data)
+	if err != nil {
+		LOG_ERROR("BENCHMARK_RAND", "Failed to generate random data: %v", err)
+		return false
+	}
+
+	startTime := float64(time.Now().UnixNano()) / 1e9
+	LOG_INFO("BENCHMARK_WRITE", "Writing random data to local disk")
+	err = ioutil.WriteFile(filename, data, 0600)
+	if err != nil {
+		LOG_ERROR("BENCHMARK_WRITE", "Failed to write the random data: %v", err)
+		return false
+	}
+
+	runningTime := float64(time.Now().UnixNano())/1e9 - startTime
+	speed := int64(float64(fileSize) / runningTime)
+	LOG_INFO("BENCHMARK_WRITE", "Wrote %s bytes in %.2fs: %s/s", PrettySize(fileSize), runningTime, PrettySize(speed))
+
+	startTime = float64(time.Now().UnixNano()) / 1e9
+	LOG_INFO("BENCHMARK_READ", "Reading the random data from local disk")
+	file, err := os.Open(filename)
+	if err != nil {
+		LOG_ERROR("BENCHMARK_OPEN", "Failed to open the random data file: %v", err)
+		return false
+	}
+	segment := make([]byte, 1024*1024)
+	for err == nil {
+		_, err = file.Read(segment)
+	}
+	if err != io.EOF {
+		LOG_ERROR("BENCHMARK_OPEN", "Failed to read the random data file: %v", err)
+		return false
+	}
+	file.Close()
+	runningTime = float64(time.Now().UnixNano())/1e9 - startTime
+	speed = int64(float64(fileSize) / runningTime)
+	LOG_INFO("BENCHMARK_READ", "Read %s bytes in %.2fs: %s/s", PrettySize(fileSize), runningTime, PrettySize(speed))
+
+	buffer := bytes.NewReader(data)
+	benchmarkSplit(buffer, fileSize, chunkSize, false, false, "without compression/encryption")
+	benchmarkSplit(buffer, fileSize, chunkSize, true, false, "with compression but without encryption")
+	benchmarkSplit(buffer, fileSize, chunkSize, true, true, "with compression and encryption")
+
+	storage.CreateDirectory(0, "benchmark")
+	existingFiles, _, err := storage.ListFiles(0, "benchmark/")
+	if err != nil {
+		LOG_ERROR("BENCHMARK_LIST", "Failed to list the benchmark directory: %v", err)
+		return false
+	}
+
+	var existingChunks []string
+	for _, f := range existingFiles {
+		if len(f) > 0 && f[len(f)-1] != '/' {
+			existingChunks = append(existingChunks, "benchmark/"+f)
+		}
+	}
+
+	if len(existingChunks) > 0 {
+		LOG_INFO("BENCHMARK_DELETE", "Deleting %d temporary files from previous benchmark runs", len(existingChunks))
+		benchmarkRun(uploadThreads, len(existingChunks), func(threadIndex int, chunkIndex int) {
+			storage.DeleteFile(threadIndex, existingChunks[chunkIndex])
+		})
+	}
+
+	chunks := make([][]byte, chunkCount)
+	chunkHashes := make([]string, chunkCount)
+	LOG_INFO("BENCHMARK_GENERATE", "Generating %d chunks", chunkCount)
+	for i := 0; i < chunkCount; i++ {
+		chunks[i] = make([]byte, chunkSize)
+		_, err = rand.Read(chunks[i])
+		if err != nil {
+			LOG_ERROR("BENCHMARK_RAND", "Failed to generate random data: %v", err)
+			return false
+		}
+		hashInBytes := sha256.Sum256(chunks[i])
+		chunkHashes[i] = hex.EncodeToString(hashInBytes[:])
+
+	}
+
+	startTime = float64(time.Now().UnixNano()) / 1e9
+	benchmarkRun(uploadThreads, chunkCount, func(threadIndex int, chunkIndex int) {
+		err := storage.UploadFile(threadIndex, fmt.Sprintf("benchmark/chunk%d", chunkIndex), chunks[chunkIndex])
+		if err != nil {
+			LOG_ERROR("BENCHMARK_UPLOAD", "Failed to upload the chunk: %v", err)
+			return
+		}
+	})
+
+	runningTime = float64(time.Now().UnixNano())/1e9 - startTime
+	speed = int64(float64(chunkSize*chunkCount) / runningTime)
+	LOG_INFO("BENCHMARK_UPLOAD", "Uploaded %s bytes in %.2fs: %s/s", PrettySize(int64(chunkSize*chunkCount)), runningTime, PrettySize(speed))
+
+	config := CreateConfig()
+
+	startTime = float64(time.Now().UnixNano()) / 1e9
+	hashError := false
+	benchmarkRun(downloadThreads, chunkCount, func(threadIndex int, chunkIndex int) {
+		chunk := config.GetChunk()
+		chunk.Reset(false)
+		err := storage.DownloadFile(threadIndex, fmt.Sprintf("benchmark/chunk%d", chunkIndex), chunk)
+		if err != nil {
+			LOG_ERROR("BENCHMARK_DOWNLOAD", "Failed to download the chunk: %v", err)
+			return
+		}
+
+		hashInBytes := sha256.Sum256(chunk.GetBytes())
+		hash := hex.EncodeToString(hashInBytes[:])
+		if hash != chunkHashes[chunkIndex] {
+			LOG_WARN("BENCHMARK_HASH", "Chunk %d has mismatched hashes: %s != %s", chunkIndex, chunkHashes[chunkIndex], hash)
+			hashError = true
+		}
+
+		config.PutChunk(chunk)
+	})
+
+	runningTime = float64(time.Now().UnixNano())/1e9 - startTime
+	speed = int64(float64(chunkSize*chunkCount) / runningTime)
+	LOG_INFO("BENCHMARK_DOWNLOAD", "Downloaded %s bytes in %.2fs: %s/s", PrettySize(int64(chunkSize*chunkCount)), runningTime, PrettySize(speed))
+
+	if !hashError {
+		benchmarkRun(uploadThreads, chunkCount, func(threadIndex int, chunkIndex int) {
+			storage.DeleteFile(threadIndex, fmt.Sprintf("benchmark/chunk%d", chunkIndex))
+		})
+		LOG_INFO("BENCHMARK_DELETE", "Deleted %d temporary files from the storage", chunkCount)
+	}
+
+	return true
+}

src/duplicacy_chunk.go

@@ -8,15 +8,22 @@ import (
 	"bytes"
 	"compress/zlib"
 	"crypto/aes"
+	"crypto/rsa"
 	"crypto/cipher"
+	"crypto/hmac"
 	"crypto/rand"
+	"crypto/sha256"
 	"encoding/hex"
+	"encoding/binary"
 	"fmt"
 	"hash"
 	"io"
+	"os"
 	"runtime"
 
 	"github.com/bkaradzic/go-lz4"
+	"github.com/minio/highwayhash"
+	"github.com/klauspost/reedsolomon"
 )
 
 // A chunk needs to acquire a new buffer and return the old one for every encrypt/decrypt operation, therefore
@@ -57,10 +64,18 @@ type Chunk struct {
 
 	config *Config // Every chunk is associated with a Config object.  Which hashing algorithm to use is determined
 	// by the config
+
+	isSnapshot bool // Indicates if the chunk is a snapshot chunk (instead of a file chunk).  This is only used by RSA
+	                // encryption, where a snapshot chunk is not encrypted by RSA
 }
 
 // Magic word to identify a duplicacy format encrypted file, plus a version number.
-var ENCRYPTION_HEADER = "duplicacy\000"
+var ENCRYPTION_BANNER = "duplicacy\000"
+
+// RSA encrypted chunks start with "duplicacy\002"
+var ENCRYPTION_VERSION_RSA byte = 2
+
+var ERASURE_CODING_BANNER = "duplicacy\003"
 
 // CreateChunk creates a new chunk.
 func CreateChunk(config *Config, bufferNeeded bool) *Chunk {
@@ -110,6 +125,7 @@ func (chunk *Chunk) Reset(hashNeeded bool) {
 	chunk.hash = nil
 	chunk.id = ""
 	chunk.size = 0
+	chunk.isSnapshot = false
 }
 
 // Write implements the Writer interface.
@@ -167,7 +183,7 @@ func (chunk *Chunk) VerifyID() {
 
 // Encrypt encrypts the plain data stored in the chunk buffer.  If derivationKey is not nil, the actual
 // encryption key will be HMAC-SHA256(encryptionKey, derivationKey).
-func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string) (err error) {
+func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string, isSnapshot bool) (err error) {
 
 	var aesBlock cipher.Block
 	var gcm cipher.AEAD
@@ -183,8 +199,17 @@ func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string) (err err
 	if len(encryptionKey) > 0 {
 
 		key := encryptionKey
-
-		if len(derivationKey) > 0 {
+		usingRSA := false
+		// Enable RSA encryption only when the chunk is not a snapshot chunk
+		if chunk.config.rsaPublicKey != nil && !isSnapshot && !chunk.isSnapshot {
+			randomKey := make([]byte, 32)
+			_, err := rand.Read(randomKey)
+			if err != nil {
+				return err
+			}
+			key = randomKey
+			usingRSA = true
+		} else if len(derivationKey) > 0 {
 			hasher := chunk.config.NewKeyedHasher([]byte(derivationKey))
 			hasher.Write(encryptionKey)
 			key = hasher.Sum(nil)
@@ -201,7 +226,21 @@ func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string) (err err
 		}
 
 		// Start with the magic number and the version number.
-		encryptedBuffer.Write([]byte(ENCRYPTION_HEADER))
+		if usingRSA {
+			// RSA encryption starts "duplicacy\002"
+			encryptedBuffer.Write([]byte(ENCRYPTION_BANNER)[:len(ENCRYPTION_BANNER) - 1])
+			encryptedBuffer.Write([]byte{ENCRYPTION_VERSION_RSA})
+
+			// Then the encrypted key
+			encryptedKey, err := rsa.EncryptOAEP(sha256.New(), rand.Reader, chunk.config.rsaPublicKey, key, nil)
+			if err != nil {
+				return err
+			}
+			binary.Write(encryptedBuffer, binary.LittleEndian, uint16(len(encryptedKey)))
+			encryptedBuffer.Write(encryptedKey)
+		} else {
+			encryptedBuffer.Write([]byte(ENCRYPTION_BANNER))
+		}
 
 		// Followed by the nonce
 		nonce = make([]byte, gcm.NonceSize())
@@ -211,10 +250,9 @@ func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string) (err err
 		}
 		encryptedBuffer.Write(nonce)
 		offset = encryptedBuffer.Len()
-
 	}
 
-	// offset is either 0 or the length of header + nonce
+	// offset is either 0 or the length of banner + nonce
 
 	if chunk.config.CompressionLevel >= -1 && chunk.config.CompressionLevel <= 9 {
 		deflater, _ := zlib.NewWriterLevel(encryptedBuffer, chunk.config.CompressionLevel)
@@ -239,34 +277,95 @@ func (chunk *Chunk) Encrypt(encryptionKey []byte, derivationKey string) (err err
 		return fmt.Errorf("Invalid compression level: %d", chunk.config.CompressionLevel)
 	}
 
-	if len(encryptionKey) == 0 {
+	if len(encryptionKey) > 0 {
+
+		// PKCS7 is used.  The sizes of compressed chunks leak information about the original chunks so we want the padding sizes
+		// to be the maximum allowed by PKCS7
+		dataLength := encryptedBuffer.Len() - offset
+		paddingLength := 256 - dataLength%256
+
+		encryptedBuffer.Write(bytes.Repeat([]byte{byte(paddingLength)}, paddingLength))
+		encryptedBuffer.Write(bytes.Repeat([]byte{0}, gcm.Overhead()))
+
+		// The encrypted data will be appended to the duplicacy banner and the once.
+		encryptedBytes := gcm.Seal(encryptedBuffer.Bytes()[:offset], nonce,
+			encryptedBuffer.Bytes()[offset:offset+dataLength+paddingLength], nil)
+
+		encryptedBuffer.Truncate(len(encryptedBytes))
+	}
+
+	if chunk.config.DataShards == 0 || chunk.config.ParityShards == 0 {
 		chunk.buffer, encryptedBuffer = encryptedBuffer, chunk.buffer
-		return nil
+		return
 	}
 
-	// PKCS7 is used.  Compressed chunk sizes leaks information about the original chunks so we want the padding sizes
-	// to be the maximum allowed by PKCS7
-	dataLength := encryptedBuffer.Len() - offset
-	paddingLength := dataLength % 256
-	if paddingLength == 0 {
-		paddingLength = 256
+	// Start erasure coding
+	encoder, err := reedsolomon.New(chunk.config.DataShards, chunk.config.ParityShards)
+	if err != nil {
+		return err
+	}
+	chunkSize := len(encryptedBuffer.Bytes())
+	shardSize := (chunkSize + chunk.config.DataShards - 1) / chunk.config.DataShards
+	// Append zeros to make the last shard to have the same size as other
+	encryptedBuffer.Write(make([]byte, shardSize * chunk.config.DataShards - chunkSize))
+	// Grow the buffer for parity shards
+	encryptedBuffer.Grow(shardSize * chunk.config.ParityShards)
+	// Now create one slice for each shard, reusing the data in the buffer
+	data := make([][]byte, chunk.config.DataShards + chunk.config.ParityShards)
+	for i := 0; i < chunk.config.DataShards + chunk.config.ParityShards; i++ {
+		data[i] = encryptedBuffer.Bytes()[i * shardSize: (i + 1) * shardSize]
+	}
+	// This populates the parity shard
+	encoder.Encode(data)
+
+	// Prepare the chunk to be uploaded
+	chunk.buffer.Reset()
+	// First the banner
+	chunk.buffer.Write([]byte(ERASURE_CODING_BANNER))
+	// Then the header which includes the chunk size, data/parity and a 2-byte checksum
+	header := make([]byte, 14)
+	binary.LittleEndian.PutUint64(header[0:], uint64(chunkSize))
+	binary.LittleEndian.PutUint16(header[8:], uint16(chunk.config.DataShards))
+	binary.LittleEndian.PutUint16(header[10:], uint16(chunk.config.ParityShards))
+	header[12] = header[0] ^ header[2] ^ header[4] ^ header[6] ^ header[8] ^ header[10]
+	header[13] = header[1] ^ header[3] ^ header[5] ^ header[7] ^ header[9] ^ header[11]
+	chunk.buffer.Write(header)
+	// Calculate the highway hash for each shard
+	hashKey := make([]byte, 32)
+	for _, part := range data {
+		hasher, err := highwayhash.New(hashKey)
+		if err != nil {
+			return err
+		}
+		_, err = hasher.Write(part)
+		if err != nil {
+			return err
+		}
+		chunk.buffer.Write(hasher.Sum(nil))
 	}
 
-	encryptedBuffer.Write(bytes.Repeat([]byte{byte(paddingLength)}, paddingLength))
-	encryptedBuffer.Write(bytes.Repeat([]byte{0}, gcm.Overhead()))
-
-	// The encrypted data will be appended to the duplicacy header and the once.
-	encryptedBytes := gcm.Seal(encryptedBuffer.Bytes()[:offset], nonce,
-		encryptedBuffer.Bytes()[offset:offset+dataLength+paddingLength], nil)
-
-	encryptedBuffer.Truncate(len(encryptedBytes))
-
-	chunk.buffer, encryptedBuffer = encryptedBuffer, chunk.buffer
+	// Copy the data
+	for _, part := range data {
+		chunk.buffer.Write(part)
+	}
+	// Append the header again for redundancy
+	chunk.buffer.Write(header)
 
 	return nil
 
 }
 
+// This is to ensure compatibility with Vertical Backup, which still uses HMAC-SHA256 (instead of HMAC-BLAKE2) to
+// derive the key used to encrypt/decrypt files and chunks.
+
+var DecryptWithHMACSHA256 = false
+
+func init() {
+	if value, found := os.LookupEnv("DUPLICACY_DECRYPT_WITH_HMACSHA256"); found && value != "0" {
+		DecryptWithHMACSHA256 = true
+	}
+}
+
 // Decrypt decrypts the encrypted data stored in the chunk buffer.  If derivationKey is not nil, the actual
 // encryption key will be HMAC-SHA256(encryptionKey, derivationKey).
 func (chunk *Chunk) Decrypt(encryptionKey []byte, derivationKey string) (err error) {
@@ -280,17 +379,174 @@ func (chunk *Chunk) Decrypt(encryptionKey []byte, derivationKey string) (err err
 	}()
 
 	chunk.buffer, encryptedBuffer = encryptedBuffer, chunk.buffer
+	bannerLength := len(ENCRYPTION_BANNER)
+
+	if len(encryptedBuffer.Bytes()) > bannerLength && string(encryptedBuffer.Bytes()[:bannerLength]) == ERASURE_CODING_BANNER {
+
+		// The chunk was encoded with erasure coding
+		if len(encryptedBuffer.Bytes()) < bannerLength + 14 {
+			return fmt.Errorf("Erasure coding header truncated (%d bytes)", len(encryptedBuffer.Bytes()))
+		}
+		// Check the header checksum
+		header := encryptedBuffer.Bytes()[bannerLength: bannerLength + 14]
+		if header[12] != header[0] ^ header[2] ^ header[4] ^ header[6] ^ header[8] ^ header[10] ||
+		   header[13] != header[1] ^ header[3] ^ header[5] ^ header[7] ^ header[9] ^ header[11] {
+			return fmt.Errorf("Erasure coding header corrupted (%x)", header)
+		}
+
+		// Read the parameters
+		chunkSize := int(binary.LittleEndian.Uint64(header[0:8]))
+		dataShards := int(binary.LittleEndian.Uint16(header[8:10]))
+		parityShards := int(binary.LittleEndian.Uint16(header[10:12]))
+		shardSize := (chunkSize + chunk.config.DataShards - 1) / chunk.config.DataShards
+		// This is the length the chunk file should have
+		expectedLength := bannerLength + 2 * len(header) + (dataShards + parityShards) * (shardSize + 32)
+		// The minimum length that can be recovered from
+		minimumLength := bannerLength + len(header) + (dataShards + parityShards) * 32 + dataShards * shardSize
+		LOG_DEBUG("CHUNK_ERASURECODE", "Chunk size: %d bytes, data size: %d, parity: %d/%d", chunkSize, len(encryptedBuffer.Bytes()), dataShards, parityShards)
+		if len(encryptedBuffer.Bytes()) > expectedLength {
+			LOG_WARN("CHUNK_ERASURECODE", "Chunk has %d bytes (instead of %d)", len(encryptedBuffer.Bytes()), expectedLength)
+		} else if len(encryptedBuffer.Bytes()) == expectedLength {
+			// Correct size; fall through
+		} else if len(encryptedBuffer.Bytes()) > minimumLength {
+			LOG_WARN("CHUNK_ERASURECODE", "Chunk is truncated (%d out of %d bytes)", len(encryptedBuffer.Bytes()), expectedLength)
+		} else {
+			return fmt.Errorf("Not enough chunk data for recovery; chunk size: %d bytes, data size: %d, parity: %d/%d", chunkSize, len(encryptedBuffer.Bytes()), dataShards, parityShards)
+		}
+
+		// Where the hashes start
+		hashOffset := bannerLength + len(header)
+		// Where the data start
+		dataOffset := hashOffset + (dataShards + parityShards) * 32
+
+		data := make([][]byte, dataShards + parityShards)
+		recoveryNeeded := false
+		hashKey := make([]byte, 32)
+		availableShards := 0
+		for i := 0; i < dataShards + parityShards; i++ {
+			start := dataOffset + i * shardSize
+			if start + shardSize > len(encryptedBuffer.Bytes()) {
+				// the current shard is incomplete
+				break
+			}
+			// Now verify the hash
+			hasher, err := highwayhash.New(hashKey)
+			if err != nil {
+				return err
+			}
+			_, err = hasher.Write(encryptedBuffer.Bytes()[start: start + shardSize])
+			if err != nil {
+				return err
+			}
+			if bytes.Compare(hasher.Sum(nil), encryptedBuffer.Bytes()[hashOffset + i * 32: hashOffset + (i + 1) * 32]) != 0 {
+				if i < dataShards {
+					recoveryNeeded = true
+				}
+			} else {
+				// The shard is good
+				data[i] = encryptedBuffer.Bytes()[start: start + shardSize]
+				availableShards++
+				if availableShards >= dataShards {
+					// We have enough shards to recover; skip the remaining shards
+					break
+				}
+			}
+		}
+
+		if !recoveryNeeded {
+			// Remove the padding zeros from the last shard
+			encryptedBuffer.Truncate(dataOffset + chunkSize)
+			// Skip the header and hashes
+			encryptedBuffer.Read(encryptedBuffer.Bytes()[:dataOffset])
+		} else {
+			if availableShards < dataShards {
+				return fmt.Errorf("Not enough chunk data for recover; only %d out of %d shards are complete", availableShards, dataShards + parityShards)
+			}
+
+			// Show the validity of shards using a string of * and -
+			slots := ""
+			for _, part := range data {
+				if len(part) != 0 {
+					slots += "*"
+				} else {
+					slots += "-"
+				}
+			}
+
+			LOG_WARN("CHUNK_ERASURECODE", "Recovering a %d byte chunk from %d byte shards: %s", chunkSize, shardSize, slots)
+			encoder, err := reedsolomon.New(dataShards, parityShards)
+			if err != nil {
+				return err
+			}
+			err = encoder.Reconstruct(data)
+			if err != nil {
+				return err
+			}
+			LOG_DEBUG("CHUNK_ERASURECODE", "Chunk data successfully recovered")
+			buffer := AllocateChunkBuffer()
+			buffer.Reset()
+			for i := 0; i < dataShards; i++ {
+				buffer.Write(data[i])
+			}
+			buffer.Truncate(chunkSize)
+
+			ReleaseChunkBuffer(encryptedBuffer)
+			encryptedBuffer = buffer
+		}
+
+	}
 
 	if len(encryptionKey) > 0 {
 
 		key := encryptionKey
 
 		if len(derivationKey) > 0 {
-			hasher := chunk.config.NewKeyedHasher([]byte(derivationKey))
+			var hasher hash.Hash
+			if DecryptWithHMACSHA256 {
+				hasher = hmac.New(sha256.New, []byte(derivationKey))
+			} else {
+				hasher = chunk.config.NewKeyedHasher([]byte(derivationKey))
+			}
+
 			hasher.Write(encryptionKey)
 			key = hasher.Sum(nil)
 		}
 
+		if len(encryptedBuffer.Bytes()) < bannerLength + 12 {
+			return fmt.Errorf("No enough encrypted data (%d bytes) provided", len(encryptedBuffer.Bytes()))
+		}
+
+		if string(encryptedBuffer.Bytes()[:bannerLength-1]) != ENCRYPTION_BANNER[:bannerLength-1] {
+			return fmt.Errorf("The storage doesn't seem to be encrypted")
+		}
+
+		encryptionVersion := encryptedBuffer.Bytes()[bannerLength-1]
+		if encryptionVersion != 0 && encryptionVersion != ENCRYPTION_VERSION_RSA {
+			return fmt.Errorf("Unsupported encryption version %d", encryptionVersion)
+		}
+
+		if encryptionVersion == ENCRYPTION_VERSION_RSA {
+			if chunk.config.rsaPrivateKey == nil {
+				LOG_ERROR("CHUNK_DECRYPT", "An RSA private key is required to decrypt the chunk")
+				return fmt.Errorf("An RSA private key is required to decrypt the chunk")
+			}
+
+			encryptedKeyLength := binary.LittleEndian.Uint16(encryptedBuffer.Bytes()[bannerLength:bannerLength+2])
+
+			if len(encryptedBuffer.Bytes()) < bannerLength + 14 + int(encryptedKeyLength) {
+				return fmt.Errorf("No enough encrypted data (%d bytes) provided", len(encryptedBuffer.Bytes()))
+			}
+
+			encryptedKey := encryptedBuffer.Bytes()[bannerLength + 2:bannerLength + 2 + int(encryptedKeyLength)]
+			bannerLength += 2 + int(encryptedKeyLength)
+
+			decryptedKey, err := rsa.DecryptOAEP(sha256.New(), rand.Reader, chunk.config.rsaPrivateKey, encryptedKey, nil)
+			if err != nil {
+				return err
+			}
+			key = decryptedKey
+		}
+
 		aesBlock, err := aes.NewCipher(key)
 		if err != nil {
 			return err
@@ -301,22 +557,8 @@ func (chunk *Chunk) Decrypt(encryptionKey []byte, derivationKey string) (err err
 			return err
 		}
 
-		headerLength := len(ENCRYPTION_HEADER)
-		offset = headerLength + gcm.NonceSize()
-
-		if len(encryptedBuffer.Bytes()) < offset {
-			return fmt.Errorf("No enough encrypted data (%d bytes) provided", len(encryptedBuffer.Bytes()))
-		}
-
-		if string(encryptedBuffer.Bytes()[:headerLength-1]) != ENCRYPTION_HEADER[:headerLength-1] {
-			return fmt.Errorf("The storage doesn't seem to be encrypted")
-		}
-
-		if encryptedBuffer.Bytes()[headerLength-1] != 0 {
-			return fmt.Errorf("Unsupported encryption version %d", encryptedBuffer.Bytes()[headerLength-1])
-		}
-
-		nonce := encryptedBuffer.Bytes()[headerLength:offset]
+		offset = bannerLength + gcm.NonceSize()
+		nonce := encryptedBuffer.Bytes()[bannerLength:offset]
 
 		decryptedBytes, err := gcm.Open(encryptedBuffer.Bytes()[:offset], nonce,
 			encryptedBuffer.Bytes()[offset:], nil)

src/duplicacy_chunk_test.go

@@ -7,11 +7,51 @@ package duplicacy
 import (
 	"bytes"
 	crypto_rand "crypto/rand"
+	"crypto/rsa"
 	"math/rand"
 	"testing"
 )
 
-func TestChunk(t *testing.T) {
+func TestErasureCoding(t *testing.T) {
+	key := []byte("duplicacydefault")
+
+	config := CreateConfig()
+	config.HashKey = key
+	config.IDKey = key
+	config.MinimumChunkSize = 100
+	config.CompressionLevel = DEFAULT_COMPRESSION_LEVEL
+	config.DataShards = 5
+    config.ParityShards = 2
+
+	chunk := CreateChunk(config, true)
+	chunk.Reset(true)
+	data := make([]byte, 100)
+	for i := 0; i < len(data); i++ {
+		data[i] = byte(i)
+	}
+	chunk.Write(data)
+	err := chunk.Encrypt([]byte(""), "", false)
+	if err != nil {
+		t.Errorf("Failed to encrypt the test data: %v", err)
+		return
+	}
+
+	encryptedData := make([]byte, chunk.GetLength())
+	copy(encryptedData, chunk.GetBytes())
+
+	crypto_rand.Read(encryptedData[280:300])
+
+	chunk.Reset(false)
+	chunk.Write(encryptedData)
+	err = chunk.Decrypt([]byte(""), "")
+	if err != nil {
+		t.Errorf("Failed to decrypt the data: %v", err)
+		return
+	}
+	return
+}
+
+func TestChunkBasic(t *testing.T) {
 
 	key := []byte("duplicacydefault")
 
@@ -22,6 +62,20 @@ func TestChunk(t *testing.T) {
 	config.CompressionLevel = DEFAULT_COMPRESSION_LEVEL
 	maxSize := 1000000
 
+	if testRSAEncryption {
+		privateKey, err := rsa.GenerateKey(crypto_rand.Reader, 2048)
+		if err != nil {
+			t.Errorf("Failed to generate a random private key: %v", err)
+		}
+		config.rsaPrivateKey = privateKey
+		config.rsaPublicKey = privateKey.Public().(*rsa.PublicKey)
+	}
+
+	if testErasureCoding {
+		config.DataShards = 5
+		config.ParityShards = 2
+	}
+
 	for i := 0; i < 500; i++ {
 
 		size := rand.Int() % maxSize
@@ -35,7 +89,7 @@ func TestChunk(t *testing.T) {
 		hash := chunk.GetHash()
 		id := chunk.GetID()
 
-		err := chunk.Encrypt(key, "")
+		err := chunk.Encrypt(key, "", false)
 		if err != nil {
 			t.Errorf("Failed to encrypt the data: %v", err)
 			continue
@@ -44,6 +98,16 @@ func TestChunk(t *testing.T) {
 		encryptedData := make([]byte, chunk.GetLength())
 		copy(encryptedData, chunk.GetBytes())
 
+		if testErasureCoding {
+			offset := 24 + 32 * 7
+			start := rand.Int() % (len(encryptedData) - offset) + offset
+			length := (len(encryptedData) - offset) / 7
+			if start + length > len(encryptedData) {
+				length = len(encryptedData) - start
+			}
+			crypto_rand.Read(encryptedData[start: start+length])
+		}
+
 		chunk.Reset(false)
 		chunk.Write(encryptedData)
 		err = chunk.Decrypt(key, "")
@@ -63,7 +127,7 @@ func TestChunk(t *testing.T) {
 		}
 
 		if bytes.Compare(plainData, decryptedData) != 0 {
-			t.Logf("orginal length: %d, decrypted length: %d", len(plainData), len(decryptedData))
+			t.Logf("Original length: %d, decrypted length: %d", len(plainData), len(decryptedData))
 			t.Errorf("Original data:\n%x\nDecrypted data:\n%x\n", plainData, decryptedData)
 		}
 

src/duplicacy_chunkdownloader.go

@@ -126,6 +126,7 @@ func (downloader *ChunkDownloader) AddFiles(snapshot *Snapshot, files []*Entry)
 
 // AddChunk adds a single chunk the download list.
 func (downloader *ChunkDownloader) AddChunk(chunkHash string) int {
+
 	task := ChunkDownloadTask{
 		chunkIndex:    len(downloader.taskList),
 		chunkHash:     chunkHash,
@@ -174,11 +175,11 @@ func (downloader *ChunkDownloader) Prefetch(file *Entry) {
 // Reclaim releases the downloaded chunk to the chunk pool
 func (downloader *ChunkDownloader) Reclaim(chunkIndex int) {
 
-	if downloader.lastChunkIndex == chunkIndex {
+	if downloader.lastChunkIndex >= chunkIndex {
 		return
 	}
 
-	for i, _ := range downloader.completedTasks {
+	for i := range downloader.completedTasks {
 		if i < chunkIndex && downloader.taskList[i].chunk != nil {
 			downloader.config.PutChunk(downloader.taskList[i].chunk)
 			downloader.taskList[i].chunk = nil
@@ -187,13 +188,30 @@ func (downloader *ChunkDownloader) Reclaim(chunkIndex int) {
 		}
 	}
 
+	for i := downloader.lastChunkIndex; i < chunkIndex; i++ {
+		// These chunks are never downloaded if 'isDownloading' is false; note that 'isDownloading' isn't reset to
+		// false after a chunk has been downloaded
+		if !downloader.taskList[i].isDownloading {
+			atomic.AddInt64(&downloader.totalChunkSize, -int64(downloader.taskList[i].chunkLength))
+		}
+	}
 	downloader.lastChunkIndex = chunkIndex
 }
 
+// Return the chunk last downloaded and its hash
+func (downloader *ChunkDownloader) GetLastDownloadedChunk() (chunk *Chunk, chunkHash string) {
+	if downloader.lastChunkIndex >= len(downloader.taskList) {
+		return nil, ""
+	}
+
+	task := downloader.taskList[downloader.lastChunkIndex]
+	return task.chunk, task.chunkHash
+}
+
 // WaitForChunk waits until the specified chunk is ready
 func (downloader *ChunkDownloader) WaitForChunk(chunkIndex int) (chunk *Chunk) {
 
-	// Reclain any chunk not needed
+	// Reclaim any chunk not needed
 	downloader.Reclaim(chunkIndex)
 
 	// If we haven't started download the specified chunk, download it now
@@ -236,6 +254,47 @@ func (downloader *ChunkDownloader) WaitForChunk(chunkIndex int) (chunk *Chunk) {
 	return downloader.taskList[chunkIndex].chunk
 }
 
+// WaitForCompletion waits until all chunks have been downloaded
+func (downloader *ChunkDownloader) WaitForCompletion() {
+
+	// Tasks in completedTasks have not been counted by numberOfActiveChunks
+	downloader.numberOfActiveChunks -= len(downloader.completedTasks)
+
+	// find the completed task with the largest index; we'll start from the next index
+	for index := range downloader.completedTasks {
+		if downloader.lastChunkIndex < index {
+			downloader.lastChunkIndex = index
+		}
+	}
+
+	// Looping until there isn't a download task in progress
+	for downloader.numberOfActiveChunks > 0 || downloader.lastChunkIndex + 1 < len(downloader.taskList) {
+
+		// Wait for a completion event first
+		if downloader.numberOfActiveChunks > 0 {
+			completion := <-downloader.completionChannel
+			downloader.config.PutChunk(completion.chunk)
+			downloader.numberOfActiveChunks--
+			downloader.numberOfDownloadedChunks++
+			downloader.numberOfDownloadingChunks--
+		}
+
+		// Pass the tasks one by one to the download queue
+		if downloader.lastChunkIndex + 1 < len(downloader.taskList) {
+			task := &downloader.taskList[downloader.lastChunkIndex + 1]
+			if task.isDownloading {
+				downloader.lastChunkIndex++
+				continue
+			}
+			downloader.taskQueue <- *task
+			task.isDownloading = true
+			downloader.numberOfDownloadingChunks++
+			downloader.numberOfActiveChunks++
+			downloader.lastChunkIndex++
+		}
+	}
+}
+
 // Stop terminates all downloading goroutines
 func (downloader *ChunkDownloader) Stop() {
 	for downloader.numberOfDownloadingChunks > 0 {
@@ -246,7 +305,7 @@ func (downloader *ChunkDownloader) Stop() {
 		downloader.numberOfDownloadingChunks--
 	}
 
-	for i, _ := range downloader.completedTasks {
+	for i := range downloader.completedTasks {
 		downloader.config.PutChunk(downloader.taskList[i].chunk)
 		downloader.taskList[i].chunk = nil
 		downloader.numberOfActiveChunks--

src/duplicacy_chunkoperator.go

@@ -0,0 +1,209 @@
+// Copyright (c) Acrosync LLC. All rights reserved.
+// Free for personal use and commercial trial
+// Commercial use requires per-user licenses available from https://duplicacy.com
+
+package duplicacy
+
+import (
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// These are operations that ChunkOperator will perform.
+const (
+	ChunkOperationFind      = 0
+	ChunkOperationDelete    = 1
+	ChunkOperationFossilize = 2
+	ChunkOperationResurrect = 3
+)
+
+// ChunkOperatorTask is used to pass parameters for different kinds of chunk operations.
+type ChunkOperatorTask struct {
+	operation int    // The type of operation
+	chunkID   string // The chunk id
+	filePath  string // The path of the chunk file; it may be empty
+}
+
+// ChunkOperator is capable of performing multi-threaded operations on chunks.
+type ChunkOperator struct {
+	numberOfActiveTasks int64                  // The number of chunks that are being operated on
+	storage             Storage                // This storage
+	threads             int                    // Number of threads
+	taskQueue           chan ChunkOperatorTask // Operating goroutines are waiting on this channel for input
+	stopChannel         chan bool              // Used to stop all the goroutines
+
+	fossils     []string    // For fossilize operation, the paths of the fossils are stored in this slice
+	fossilsLock *sync.Mutex // The lock for 'fossils'
+}
+
+// CreateChunkOperator creates a new ChunkOperator.
+func CreateChunkOperator(storage Storage, threads int) *ChunkOperator {
+	operator := &ChunkOperator{
+		storage: storage,
+		threads: threads,
+
+		taskQueue:   make(chan ChunkOperatorTask, threads*4),
+		stopChannel: make(chan bool),
+
+		fossils:     make([]string, 0),
+		fossilsLock: &sync.Mutex{},
+	}
+
+	// Start the operator goroutines
+	for i := 0; i < operator.threads; i++ {
+		go func(threadIndex int) {
+			defer CatchLogException()
+			for {
+				select {
+				case task := <-operator.taskQueue:
+					operator.Run(threadIndex, task)
+				case <-operator.stopChannel:
+					return
+				}
+			}
+		}(i)
+	}
+
+	return operator
+}
+
+func (operator *ChunkOperator) Stop() {
+	if atomic.LoadInt64(&operator.numberOfActiveTasks) < 0 {
+		return
+	}
+
+	for atomic.LoadInt64(&operator.numberOfActiveTasks) > 0 {
+		time.Sleep(100 * time.Millisecond)
+	}
+	for i := 0; i < operator.threads; i++ {
+		operator.stopChannel <- false
+	}
+
+	// Assign -1 to numberOfActiveTasks so Stop() can be called multiple times
+	atomic.AddInt64(&operator.numberOfActiveTasks, int64(-1))
+}
+
+func (operator *ChunkOperator) AddTask(operation int, chunkID string, filePath string) {
+
+	task := ChunkOperatorTask{
+		operation: operation,
+		chunkID:   chunkID,
+		filePath:  filePath,
+	}
+	operator.taskQueue <- task
+	atomic.AddInt64(&operator.numberOfActiveTasks, int64(1))
+}
+
+func (operator *ChunkOperator) Find(chunkID string) {
+	operator.AddTask(ChunkOperationFind, chunkID, "")
+}
+
+func (operator *ChunkOperator) Delete(chunkID string, filePath string) {
+	operator.AddTask(ChunkOperationDelete, chunkID, filePath)
+}
+
+func (operator *ChunkOperator) Fossilize(chunkID string, filePath string) {
+	operator.AddTask(ChunkOperationFossilize, chunkID, filePath)
+}
+
+func (operator *ChunkOperator) Resurrect(chunkID string, filePath string) {
+	operator.AddTask(ChunkOperationResurrect, chunkID, filePath)
+}
+
+func (operator *ChunkOperator) Run(threadIndex int, task ChunkOperatorTask) {
+	defer func() {
+		atomic.AddInt64(&operator.numberOfActiveTasks, int64(-1))
+	}()
+
+	// task.filePath may be empty.  If so, find the chunk first.
+	if task.operation == ChunkOperationDelete || task.operation == ChunkOperationFossilize {
+		if task.filePath == "" {
+			filePath, exist, _, err := operator.storage.FindChunk(threadIndex, task.chunkID, false)
+			if err != nil {
+				LOG_ERROR("CHUNK_FIND", "Failed to locate the path for the chunk %s: %v", task.chunkID, err)
+				return
+			} else if !exist {
+				if task.operation == ChunkOperationDelete {
+					LOG_WARN("CHUNK_FIND", "Chunk %s does not exist in the storage", task.chunkID)
+					return
+				}
+
+				fossilPath, exist, _, _ := operator.storage.FindChunk(threadIndex, task.chunkID, true)
+				if exist {
+					LOG_WARN("CHUNK_FOSSILIZE", "Chunk %s is already a fossil", task.chunkID)
+					operator.fossilsLock.Lock()
+					operator.fossils = append(operator.fossils, fossilPath)
+					operator.fossilsLock.Unlock()
+				} else {
+					LOG_ERROR("CHUNK_FIND", "Chunk %s does not exist in the storage", task.chunkID)
+				}
+				return
+			}
+			task.filePath = filePath
+		}
+	}
+
+	if task.operation == ChunkOperationFind {
+		_, exist, _, err := operator.storage.FindChunk(threadIndex, task.chunkID, false)
+		if err != nil {
+			LOG_ERROR("CHUNK_FIND", "Failed to locate the path for the chunk %s: %v", task.chunkID, err)
+		} else if !exist {
+			LOG_ERROR("CHUNK_FIND", "Chunk %s does not exist in the storage", task.chunkID)
+		} else {
+			LOG_DEBUG("CHUNK_FIND", "Chunk %s exists in the storage", task.chunkID)
+		}
+	} else if task.operation == ChunkOperationDelete {
+		err := operator.storage.DeleteFile(threadIndex, task.filePath)
+		if err != nil {
+			LOG_WARN("CHUNK_DELETE", "Failed to remove the file %s: %v", task.filePath, err)
+		} else {
+			if task.chunkID != "" {
+				LOG_INFO("CHUNK_DELETE", "The chunk %s has been permanently removed", task.chunkID)
+			} else {
+				LOG_INFO("CHUNK_DELETE", "Deleted file %s from the storage", task.filePath)
+			}
+		}
+	} else if task.operation == ChunkOperationFossilize {
+
+		fossilPath := task.filePath + ".fsl"
+
+		err := operator.storage.MoveFile(threadIndex, task.filePath, fossilPath)
+		if err != nil {
+			if _, exist, _, _ := operator.storage.FindChunk(threadIndex, task.chunkID, true); exist {
+				err := operator.storage.DeleteFile(threadIndex, task.filePath)
+				if err == nil {
+					LOG_TRACE("CHUNK_DELETE", "Deleted chunk file %s as the fossil already exists", task.chunkID)
+				}
+				operator.fossilsLock.Lock()
+				operator.fossils = append(operator.fossils, fossilPath)
+				operator.fossilsLock.Unlock()
+			} else {
+				LOG_ERROR("CHUNK_DELETE", "Failed to fossilize the chunk %s: %v", task.chunkID, err)
+			}
+		} else {
+			LOG_TRACE("CHUNK_FOSSILIZE", "The chunk %s has been marked as a fossil", task.chunkID)
+			operator.fossilsLock.Lock()
+			operator.fossils = append(operator.fossils, fossilPath)
+			operator.fossilsLock.Unlock()
+		}
+	} else if task.operation == ChunkOperationResurrect {
+		chunkPath, exist, _, err := operator.storage.FindChunk(threadIndex, task.chunkID, false)
+		if err != nil {
+			LOG_ERROR("CHUNK_FIND", "Failed to locate the path for the chunk %s: %v", task.chunkID, err)
+		}
+
+		if exist {
+			operator.storage.DeleteFile(threadIndex, task.filePath)
+			LOG_INFO("FOSSIL_RESURRECT", "The chunk %s already exists", task.chunkID)
+		} else {
+			err := operator.storage.MoveFile(threadIndex, task.filePath, chunkPath)
+			if err != nil {
+				LOG_ERROR("FOSSIL_RESURRECT", "Failed to resurrect the chunk %s from the fossil %s: %v",
+					task.chunkID, task.filePath, err)
+			} else {
+				LOG_INFO("FOSSIL_RESURRECT", "The chunk %s has been resurrected", task.filePath)
+			}
+		}
+	}
+}

src/duplicacy_chunkuploader.go

@@ -128,7 +128,7 @@ func (uploader *ChunkUploader) Upload(threadIndex int, task ChunkUploadTask) boo
 	}
 
 	// Encrypt the chunk only after we know that it must be uploaded.
-	err = chunk.Encrypt(uploader.config.ChunkKey, chunk.GetHash())
+	err = chunk.Encrypt(uploader.config.ChunkKey, chunk.GetHash(), uploader.snapshotCache != nil)
 	if err != nil {
 		LOG_ERROR("UPLOAD_CHUNK", "Failed to encrypt the chunk %s: %v", chunkID, err)
 		return false

src/duplicacy_chunkuploader_test.go

@@ -111,7 +111,7 @@ func TestUploaderAndDownloader(t *testing.T) {
 	for i, chunk := range chunks {
 		downloaded := chunkDownloader.WaitForChunk(i)
 		if downloaded.GetID() != chunk.GetID() {
-			t.Error("Uploaded: %s, downloaded: %s", chunk.GetID(), downloaded.GetID())
+			t.Errorf("Uploaded: %s, downloaded: %s", chunk.GetID(), downloaded.GetID())
 		}
 	}
 

src/duplicacy_config.go

@@ -9,15 +9,20 @@ import (
 	"crypto/hmac"
 	"crypto/rand"
 	"crypto/sha256"
+	"crypto/rsa"
+	"crypto/x509"
 	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
+	"encoding/pem"
 	"fmt"
 	"hash"
 	"os"
 	"runtime"
 	"runtime/debug"
 	"sync/atomic"
+	"io/ioutil"
+	"reflect"
 
 	blake2 "github.com/minio/blake2b-simd"
 )
@@ -29,8 +34,8 @@ var DEFAULT_KEY = []byte("duplicacy")
 // standard zlib levels of -1 to 9.
 var DEFAULT_COMPRESSION_LEVEL = 100
 
-// The new header of the config file (to differentiate from the old format where the salt and iterations are fixed)
-var CONFIG_HEADER = "duplicacy\001"
+// The new banner of the config file (to differentiate from the old format where the salt and iterations are fixed)
+var CONFIG_BANNER = "duplicacy\001"
 
 // The length of the salt used in the new format
 var CONFIG_SALT_LENGTH = 32
@@ -65,6 +70,14 @@ type Config struct {
 	// for encrypting a non-chunk file
 	FileKey []byte `json:"-"`
 
+	// for erasure coding
+	DataShards int `json:'data-shards'`
+	ParityShards int `json:'parity-shards'`
+
+	// for RSA encryption
+	rsaPrivateKey *rsa.PrivateKey
+	rsaPublicKey *rsa.PublicKey
+
 	chunkPool      chan *Chunk
 	numberOfChunks int32
 	dryRun         bool
@@ -80,10 +93,15 @@ type jsonableConfig struct {
 	IDKey     string `json:"id-key"`
 	ChunkKey  string `json:"chunk-key"`
 	FileKey   string `json:"file-key"`
+	RSAPublicKey string `json:"rsa-public-key"`
 }
 
 func (config *Config) MarshalJSON() ([]byte, error) {
 
+	publicKey := []byte {}
+	if config.rsaPublicKey != nil {
+		publicKey, _ = x509.MarshalPKIXPublicKey(config.rsaPublicKey)
+	}
 	return json.Marshal(&jsonableConfig{
 		aliasedConfig: (*aliasedConfig)(config),
 		ChunkSeed:     hex.EncodeToString(config.ChunkSeed),
@@ -91,6 +109,7 @@ func (config *Config) MarshalJSON() ([]byte, error) {
 		IDKey:         hex.EncodeToString(config.IDKey),
 		ChunkKey:      hex.EncodeToString(config.ChunkKey),
 		FileKey:       hex.EncodeToString(config.FileKey),
+		RSAPublicKey:  hex.EncodeToString(publicKey),
 	})
 }
 
@@ -120,6 +139,19 @@ func (config *Config) UnmarshalJSON(description []byte) (err error) {
 		return fmt.Errorf("Invalid representation of the file key in the config")
 	}
 
+	if publicKey, err := hex.DecodeString(aliased.RSAPublicKey); err != nil {
+		return fmt.Errorf("Invalid hex encoding of the RSA public key in the config")
+	} else if len(publicKey) > 0 {
+		parsedKey, err := x509.ParsePKIXPublicKey(publicKey)
+		if err != nil {
+			return fmt.Errorf("Invalid RSA public key in the config: %v", err)
+		}
+		config.rsaPublicKey = parsedKey.(*rsa.PublicKey)
+		if config.rsaPublicKey == nil {
+			return fmt.Errorf("Unsupported public key type %s in the config", reflect.TypeOf(parsedKey))
+		}
+	}
+
 	return nil
 }
 
@@ -140,6 +172,33 @@ func (config *Config) Print() {
 	LOG_INFO("CONFIG_INFO", "Maximum chunk size: %d", config.MaximumChunkSize)
 	LOG_INFO("CONFIG_INFO", "Minimum chunk size: %d", config.MinimumChunkSize)
 	LOG_INFO("CONFIG_INFO", "Chunk seed: %x", config.ChunkSeed)
+
+	LOG_TRACE("CONFIG_INFO", "Hash key: %x", config.HashKey)
+	LOG_TRACE("CONFIG_INFO", "ID key: %x", config.IDKey)
+
+	if len(config.ChunkKey) > 0 {
+		LOG_TRACE("CONFIG_INFO", "File chunks are encrypted")
+	}
+
+	if len(config.FileKey) > 0 {
+		LOG_TRACE("CONFIG_INFO", "Metadata chunks are encrypted")
+	}
+
+	if config.DataShards != 0 && config.ParityShards != 0 {
+		LOG_TRACE("CONFIG_INFO", "Data shards: %d, parity shards: %d", config.DataShards, config.ParityShards)
+	}
+
+	if config.rsaPublicKey != nil {
+		pkisPublicKey, _ := x509.MarshalPKIXPublicKey(config.rsaPublicKey)
+
+		publicKey := pem.EncodeToMemory(&pem.Block{
+			Type:  "PUBLIC KEY",
+			Bytes: pkisPublicKey,
+		})
+
+		LOG_TRACE("CONFIG_INFO", "RSA public key: %s", publicKey)
+	}
+
 }
 
 func CreateConfigFromParameters(compressionLevel int, averageChunkSize int, maximumChunkSize int, mininumChunkSize int,
@@ -335,11 +394,11 @@ func DownloadConfig(storage Storage, password string) (config *Config, isEncrypt
 		return nil, false, err
 	}
 
-	if len(configFile.GetBytes()) < len(ENCRYPTION_HEADER) {
+	if len(configFile.GetBytes()) < len(ENCRYPTION_BANNER) {
 		return nil, false, fmt.Errorf("The storage has an invalid config file")
 	}
 
-	if string(configFile.GetBytes()[:len(ENCRYPTION_HEADER)-1]) == ENCRYPTION_HEADER[:len(ENCRYPTION_HEADER)-1] && len(password) == 0 {
+	if string(configFile.GetBytes()[:len(ENCRYPTION_BANNER)-1]) == ENCRYPTION_BANNER[:len(ENCRYPTION_BANNER)-1] && len(password) == 0 {
 		return nil, true, fmt.Errorf("The storage is likely to have been initialized with a password before")
 	}
 
@@ -347,23 +406,23 @@ func DownloadConfig(storage Storage, password string) (config *Config, isEncrypt
 
 	if len(password) > 0 {
 
-		if string(configFile.GetBytes()[:len(ENCRYPTION_HEADER)]) == ENCRYPTION_HEADER {
+		if string(configFile.GetBytes()[:len(ENCRYPTION_BANNER)]) == ENCRYPTION_BANNER {
 			// This is the old config format with a static salt and a fixed number of iterations
 			masterKey = GenerateKeyFromPassword(password, DEFAULT_KEY, CONFIG_DEFAULT_ITERATIONS)
 			LOG_TRACE("CONFIG_FORMAT", "Using a static salt and %d iterations for key derivation", CONFIG_DEFAULT_ITERATIONS)
-		} else if string(configFile.GetBytes()[:len(CONFIG_HEADER)]) == CONFIG_HEADER {
+		} else if string(configFile.GetBytes()[:len(CONFIG_BANNER)]) == CONFIG_BANNER {
 			// This is the new config format with a random salt and a configurable number of iterations
 			encryptedLength := len(configFile.GetBytes()) - CONFIG_SALT_LENGTH - 4
 
 			// Extract the salt and the number of iterations
-			saltStart := configFile.GetBytes()[len(CONFIG_HEADER):]
+			saltStart := configFile.GetBytes()[len(CONFIG_BANNER):]
 			iterations := binary.LittleEndian.Uint32(saltStart[CONFIG_SALT_LENGTH : CONFIG_SALT_LENGTH+4])
 			LOG_TRACE("CONFIG_ITERATIONS", "Using %d iterations for key derivation", iterations)
 			masterKey = GenerateKeyFromPassword(password, saltStart[:CONFIG_SALT_LENGTH], int(iterations))
 
-			// Copy to a temporary buffer to replace the header and remove the salt and the number of riterations
+			// Copy to a temporary buffer to replace the banner and remove the salt and the number of riterations
 			var encrypted bytes.Buffer
-			encrypted.Write([]byte(ENCRYPTION_HEADER))
+			encrypted.Write([]byte(ENCRYPTION_BANNER))
 			encrypted.Write(saltStart[CONFIG_SALT_LENGTH+4:])
 
 			configFile.Reset(false)
@@ -372,7 +431,7 @@ func DownloadConfig(storage Storage, password string) (config *Config, isEncrypt
 				LOG_ERROR("CONFIG_DOWNLOAD", "Encrypted config has %d bytes instead of expected %d bytes", len(configFile.GetBytes()), encryptedLength)
 			}
 		} else {
-			return nil, true, fmt.Errorf("The config file has an invalid header")
+			return nil, true, fmt.Errorf("The config file has an invalid banner")
 		}
 
 		// Decrypt the config file.  masterKey == nil means no encryption.
@@ -430,21 +489,21 @@ func UploadConfig(storage Storage, config *Config, password string, iterations i
 
 	if len(password) > 0 {
 		// Encrypt the config file with masterKey.  If masterKey is nil then no encryption is performed.
-		err = chunk.Encrypt(masterKey, "")
+		err = chunk.Encrypt(masterKey, "", true)
 		if err != nil {
 			LOG_ERROR("CONFIG_CREATE", "Failed to create the config file: %v", err)
 			return false
 		}
 
-		// The new encrypted format for config is CONFIG_HEADER + salt + #iterations + encrypted content
+		// The new encrypted format for config is CONFIG_BANNER + salt + #iterations + encrypted content
 		encryptedLength := len(chunk.GetBytes()) + CONFIG_SALT_LENGTH + 4
 
-		// Copy to a temporary buffer to replace the header and add the salt and the number of iterations
+		// Copy to a temporary buffer to replace the banner and add the salt and the number of iterations
 		var encrypted bytes.Buffer
-		encrypted.Write([]byte(CONFIG_HEADER))
+		encrypted.Write([]byte(CONFIG_BANNER))
 		encrypted.Write(salt)
 		binary.Write(&encrypted, binary.LittleEndian, uint32(iterations))
-		encrypted.Write(chunk.GetBytes()[len(ENCRYPTION_HEADER):])
+		encrypted.Write(chunk.GetBytes()[len(ENCRYPTION_BANNER):])
 
 		chunk.Reset(false)
 		chunk.Write(encrypted.Bytes())
@@ -477,7 +536,7 @@ func UploadConfig(storage Storage, config *Config, password string, iterations i
 // it simply creates a file named 'config' that stores various parameters as well as a set of keys if encryption
 // is enabled.
 func ConfigStorage(storage Storage, iterations int, compressionLevel int, averageChunkSize int, maximumChunkSize int,
-	minimumChunkSize int, password string, copyFrom *Config, bitCopy bool) bool {
+	minimumChunkSize int, password string, copyFrom *Config, bitCopy bool, keyFile string, dataShards int, parityShards int) bool {
 
 	exist, _, _, err := storage.GetFileInfo(0, "config")
 	if err != nil {
@@ -496,5 +555,117 @@ func ConfigStorage(storage Storage, iterations int, compressionLevel int, averag
 		return false
 	}
 
+	if keyFile != "" {
+		config.loadRSAPublicKey(keyFile)
+	}
+
+	config.DataShards = dataShards
+	config.ParityShards = parityShards
+
 	return UploadConfig(storage, config, password, iterations)
 }
+
+func (config *Config) loadRSAPublicKey(keyFile string) {
+	encodedKey, err := ioutil.ReadFile(keyFile)
+	if err != nil {
+		LOG_ERROR("BACKUP_KEY", "Failed to read the public key file: %v", err)
+		return
+	}
+
+	decodedKey, _ := pem.Decode(encodedKey)
+	if decodedKey == nil {
+		LOG_ERROR("RSA_PUBLIC", "unrecognized public key in %s", keyFile)
+		return
+	}
+	if decodedKey.Type != "PUBLIC KEY" {
+		LOG_ERROR("RSA_PUBLIC", "Unsupported public key type %s in %s", decodedKey.Type, keyFile)
+		return
+	}
+
+	parsedKey, err := x509.ParsePKIXPublicKey(decodedKey.Bytes)
+	if err != nil {
+		LOG_ERROR("RSA_PUBLIC", "Failed to parse the public key in %s: %v", keyFile, err)
+		return
+	}
+
+	key, ok := parsedKey.(*rsa.PublicKey)
+	if !ok {
+		LOG_ERROR("RSA_PUBLIC", "Unsupported public key type %s in %s", reflect.TypeOf(parsedKey), keyFile)
+		return
+	}
+
+	config.rsaPublicKey = key
+}
+
+// loadRSAPrivateKey loads the specifed private key file for decrypting file chunks
+func (config *Config) loadRSAPrivateKey(keyFile string, passphrase string) {
+
+	if config.rsaPublicKey == nil {
+		LOG_ERROR("RSA_PUBLIC", "The storage was not encrypted by an RSA key")
+		return
+	}
+
+	encodedKey, err := ioutil.ReadFile(keyFile)
+	if err != nil {
+		LOG_ERROR("RSA_PRIVATE", "Failed to read the private key file: %v", err)
+		return
+	}
+
+	decodedKey, _ := pem.Decode(encodedKey)
+	if decodedKey == nil {
+		LOG_ERROR("RSA_PRIVATE", "unrecognized private key in %s", keyFile)
+		return
+	}
+	if decodedKey.Type != "RSA PRIVATE KEY" {
+		LOG_ERROR("RSA_PRIVATE", "Unsupported private key type %s in %s", decodedKey.Type, keyFile)
+		return
+	}
+
+	var decodedKeyBytes []byte
+	if passphrase != "" {
+		decodedKeyBytes, err = x509.DecryptPEMBlock(decodedKey, []byte(passphrase))
+	} else {
+		decodedKeyBytes = decodedKey.Bytes
+	}
+
+	var parsedKey interface{}
+	if parsedKey, err = x509.ParsePKCS1PrivateKey(decodedKeyBytes); err != nil {
+		if parsedKey, err = x509.ParsePKCS8PrivateKey(decodedKeyBytes); err != nil {
+			LOG_ERROR("RSA_PRIVATE", "Failed to parse the private key in %s: %v", keyFile, err)
+			return
+		}
+	}
+
+	key, ok := parsedKey.(*rsa.PrivateKey)
+	if !ok {
+		LOG_ERROR("RSA_PRIVATE", "Unsupported private key type %s in %s", reflect.TypeOf(parsedKey), keyFile)
+		return
+	}
+
+	data := make([]byte, 32)
+	_, err = rand.Read(data)
+	if err != nil {
+		LOG_ERROR("RSA_PRIVATE", "Failed to generate random data for testing the private key: %v", err)
+		return
+	}
+
+	// Now test if the private key matches the public key
+	encryptedData, err := rsa.EncryptOAEP(sha256.New(), rand.Reader, config.rsaPublicKey, data, nil)
+	if err != nil {
+		LOG_ERROR("RSA_PRIVATE", "Failed to encrypt random data with the public key: %v", err)
+		return
+	}
+
+	decryptedData, err := rsa.DecryptOAEP(sha256.New(), rand.Reader, key, encryptedData, nil)
+	if err != nil {
+		LOG_ERROR("RSA_PRIVATE", "Incorrect private key: %v", err)
+		return
+	}
+
+	if !bytes.Equal(data, decryptedData) {
+		LOG_ERROR("RSA_PRIVATE", "Decrypted data do not match the original data")
+		return
+	}
+
+	config.rsaPrivateKey = key
+}

src/duplicacy_dropboxstorage.go

@@ -6,6 +6,7 @@ package duplicacy
 
 import (
 	"fmt"
+	"io/ioutil"
 	"strings"
 
 	"github.com/gilbertchen/go-dropbox"
@@ -199,6 +200,7 @@ func (storage *DropboxStorage) DownloadFile(threadIndex int, filePath string, ch
 	}
 
 	defer output.Body.Close()
+	defer ioutil.ReadAll(output.Body)
 
 	_, err = RateLimitedCopy(chunk, output.Body, storage.DownloadRateLimit/len(storage.clients))
 	return err

src/duplicacy_entry.go

@@ -22,6 +22,9 @@ import (
 var DUPLICACY_DIRECTORY = ".duplicacy"
 var DUPLICACY_FILE = ".duplicacy"
 
+// Mask for file permission bits
+var fileModeMask = os.ModePerm | os.ModeSetuid | os.ModeSetgid | os.ModeSticky
+
 // Regex for matching 'StartChunk:StartOffset:EndChunk:EndOffset'
 var contentRegex = regexp.MustCompile(`^([0-9]+):([0-9]+):([0-9]+):([0-9]+)`)
 
@@ -269,7 +272,7 @@ func (entry *Entry) IsLink() bool {
 }
 
 func (entry *Entry) GetPermissions() os.FileMode {
-	return os.FileMode(entry.Mode) & os.ModePerm
+	return os.FileMode(entry.Mode) & fileModeMask
 }
 
 func (entry *Entry) IsSameAs(other *Entry) bool {
@@ -289,7 +292,7 @@ func (entry *Entry) String(maxSizeDigits int) string {
 func (entry *Entry) RestoreMetadata(fullPath string, fileInfo *os.FileInfo, setOwner bool) bool {
 
 	if fileInfo == nil {
-		stat, err := os.Stat(fullPath)
+		stat, err := os.Lstat(fullPath)
 		fileInfo = &stat
 		if err != nil {
 			LOG_ERROR("RESTORE_STAT", "Failed to retrieve the file info: %v", err)
@@ -297,7 +300,15 @@ func (entry *Entry) RestoreMetadata(fullPath string, fileInfo *os.FileInfo, setO
 		}
 	}
 
-	if (*fileInfo).Mode()&os.ModePerm != entry.GetPermissions() {
+	// Note that chown can remove setuid/setgid bits so should be called before chmod
+	if setOwner {
+		if !SetOwner(fullPath, entry, fileInfo) {
+			return false
+		}
+	}
+
+	// Only set the permission if the file is not a symlink
+	if !entry.IsLink() && (*fileInfo).Mode()&fileModeMask != entry.GetPermissions() {
 		err := os.Chmod(fullPath, entry.GetPermissions())
 		if err != nil {
 			LOG_ERROR("RESTORE_CHMOD", "Failed to set the file permissions: %v", err)
@@ -305,7 +316,8 @@ func (entry *Entry) RestoreMetadata(fullPath string, fileInfo *os.FileInfo, setO
 		}
 	}
 
-	if (*fileInfo).ModTime().Unix() != entry.Time {
+	// Only set the time if the file is not a symlink
+	if !entry.IsLink() && (*fileInfo).ModTime().Unix() != entry.Time {
 		modifiedTime := time.Unix(entry.Time, 0)
 		err := os.Chtimes(fullPath, modifiedTime, modifiedTime)
 		if err != nil {
@@ -318,11 +330,7 @@ func (entry *Entry) RestoreMetadata(fullPath string, fileInfo *os.FileInfo, setO
 		entry.SetAttributesToFile(fullPath)
 	}
 
-	if setOwner {
-		return SetOwner(fullPath, entry, fileInfo)
-	} else {
-		return true
-	}
+	return true
 }
 
 // Return -1 if 'left' should appear before 'right', 1 if opposite, and 0 if they are the same.
@@ -435,7 +443,7 @@ func (files FileInfoCompare) Less(i, j int) bool {
 
 // ListEntries returns a list of entries representing file and subdirectories under the directory 'path'.  Entry paths
 // are normalized as relative to 'top'.  'patterns' are used to exclude or include certain files.
-func ListEntries(top string, path string, fileList *[]*Entry, patterns []string, discardAttributes bool) (directoryList []*Entry,
+func ListEntries(top string, path string, fileList *[]*Entry, patterns []string, nobackupFile string, discardAttributes bool) (directoryList []*Entry,
 	skippedFiles []string, err error) {
 
 	LOG_DEBUG("LIST_ENTRIES", "Listing %s", path)
@@ -449,6 +457,15 @@ func ListEntries(top string, path string, fileList *[]*Entry, patterns []string,
 		return directoryList, nil, err
 	}
 
+	// This binary search works because ioutil.ReadDir returns files sorted by Name() by default
+	if nobackupFile != "" {
+		ii := sort.Search(len(files), func(ii int) bool { return strings.Compare(files[ii].Name(), nobackupFile) >= 0 })
+		if ii < len(files) && files[ii].Name() == nobackupFile {
+			LOG_DEBUG("LIST_NOBACKUP", "%s is excluded due to nobackup file", path)
+			return directoryList, skippedFiles, nil
+		}
+	}
+
 	normalizedPath := path
 	if len(normalizedPath) > 0 && normalizedPath[len(normalizedPath)-1] != '/' {
 		normalizedPath += "/"
@@ -469,12 +486,11 @@ func ListEntries(top string, path string, fileList *[]*Entry, patterns []string,
 		}
 		entry := CreateEntryFromFileInfo(f, normalizedPath)
 		if len(patterns) > 0 && !MatchPath(entry.Path, patterns) {
-			LOG_DEBUG("LIST_EXCLUDE", "%s is excluded", entry.Path)
 			continue
 		}
 		if entry.IsLink() {
 			isRegular := false
-			isRegular, entry.Link, err = Readlink(filepath.Join(top, entry.Path))
+			isRegular, entry.Link, err = Readlink(joinPath(top, entry.Path))
 			if err != nil {
 				LOG_WARN("LIST_LINK", "Failed to read the symlink %s: %v", entry.Path, err)
 				skippedFiles = append(skippedFiles, entry.Path)
@@ -484,7 +500,7 @@ func ListEntries(top string, path string, fileList *[]*Entry, patterns []string,
 			if isRegular {
 				entry.Mode ^= uint32(os.ModeSymlink)
 			} else if path == "" && (filepath.IsAbs(entry.Link) || filepath.HasPrefix(entry.Link, `\\`)) && !strings.HasPrefix(entry.Link, normalizedTop) {
-				stat, err := os.Stat(filepath.Join(top, entry.Path))
+				stat, err := os.Stat(joinPath(top, entry.Path))
 				if err != nil {
 					LOG_WARN("LIST_LINK", "Failed to read the symlink: %v", err)
 					skippedFiles = append(skippedFiles, entry.Path)
@@ -497,6 +513,9 @@ func ListEntries(top string, path string, fileList *[]*Entry, patterns []string,
 					// path from f.Name(); note that a "/" is append assuming a symbolic link is always a directory
 					newEntry.Path = filepath.Join(normalizedPath, f.Name()) + "/"
 				}
+				if len(patterns) > 0 && !MatchPath(newEntry.Path, patterns) {
+					continue
+				}
 				entry = newEntry
 			}
 		}

src/duplicacy_entry_test.go

@@ -173,7 +173,7 @@ func TestEntryList(t *testing.T) {
 		directory := directories[len(directories)-1]
 		directories = directories[:len(directories)-1]
 		entries = append(entries, directory)
-		subdirectories, _, err := ListEntries(testDir, directory.Path, &entries, nil, false)
+		subdirectories, _, err := ListEntries(testDir, directory.Path, &entries, nil, "", false)
 		if err != nil {
 			t.Errorf("ListEntries(%s, %s) returned an error: %s", testDir, directory.Path, err)
 		}

src/duplicacy_filefabricstorage.go

@@ -0,0 +1,618 @@
+// Copyright (c) Storage Made Easy. All rights reserved.
+// 
+// This storage backend is contributed by Storage Made Easy (https://storagemadeeasy.com/) to be used in
+// Duplicacy and its derivative works.
+//
+
+package duplicacy
+
+import (
+	"io"
+	"fmt"
+	"time"
+	"sync"
+	"bytes"
+	"errors"
+	"strings"
+	"net/url"
+	"net/http"
+	"math/rand"
+	"io/ioutil"
+	"encoding/xml"
+	"path/filepath"
+	"mime/multipart"
+)
+
+// The XML element representing a file returned by the File Fabric server
+type FileFabricFile struct {
+	XMLName     xml.Name
+	ID          string     `xml:"fi_id"`
+	Path        string     `xml:"path"`
+	Size        int64      `xml:"fi_size"`
+	Type        int        `xml:"fi_type"`
+}
+
+// The XML element representing a file list returned by the server
+type FileFabricFileList struct {
+	XMLName xml.Name `xml:"files"`
+	Files []FileFabricFile `xml:",any"`
+}
+
+type FileFabricStorage struct {
+	StorageBase
+
+	endpoint           string            // the server
+	authToken          string            // the authentication token
+	accessToken        string            // the access token (as returned by getTokenByAuthToken)
+	storageDir         string            // the path of the storage directory
+	storageDirID       string            // the id of 'storageDir'
+
+	client             *http.Client      // the default http client
+	threads            int               // number of threads
+	maxRetries         int               // maximum number of tries
+	directoryCache     map[string]string // stores ids for directories known to this backend
+	directoryCacheLock sync.Mutex        // lock for accessing directoryCache
+
+	isAuthorized       bool
+	testMode           bool
+}
+
+var (
+	errFileFabricAuthorizationFailure = errors.New("Authentication failure")
+	errFileFabricDirectoryExists = errors.New("Directory exists")
+)
+
+// The general server response
+type FileFabricResponse struct {
+	Status string `xml:"status"`
+	Message string `xml:"statusmessage"`
+}
+
+// Check the server response and return an error representing the error message it contains
+func checkFileFabricResponse(response FileFabricResponse, actionFormat string, actionArguments ...interface{}) error {
+
+	action := fmt.Sprintf(actionFormat, actionArguments...)
+	if response.Status == "ok" && response.Message == "Success" {
+		return nil
+	} else if response.Status == "error_data" {
+		if response.Message == "Folder with same name already exists." {
+			return errFileFabricDirectoryExists
+		}
+	}
+
+	return fmt.Errorf("Failed to %s (status: %s, message: %s)", action, response.Status, response.Message)
+}
+
+// Create a File Fabric storage backend
+func CreateFileFabricStorage(endpoint string, token string, storageDir string, threads int) (storage *FileFabricStorage, err error) {
+
+	if len(storageDir) > 0 && storageDir[len(storageDir)-1] != '/' {
+		storageDir += "/"
+	}
+
+	storage = &FileFabricStorage{
+
+		endpoint:       endpoint,
+		authToken:      token,
+		client:         http.DefaultClient,
+		threads:        threads,
+		directoryCache: make(map[string]string),
+		maxRetries:     12,
+	}
+
+	err = storage.getAccessToken()
+	if err != nil {
+		return nil, err
+	}
+
+	storageDirID, isDir, _, err := storage.getFileInfo(0, storageDir)
+	if err != nil {
+		return nil, err
+	}
+	if storageDirID == "" {
+		return nil, fmt.Errorf("Storage path %s does not exist", storageDir)
+	}
+	if !isDir {
+		return nil, fmt.Errorf("Storage path %s is not a directory", storageDir)
+	}
+	storage.storageDir = storageDir
+	storage.storageDirID = storageDirID
+
+	for _, dir := range []string{"snapshots", "chunks"} {
+		storage.CreateDirectory(0, dir)
+	}
+
+	storage.DerivedStorage = storage
+	storage.SetDefaultNestingLevels([]int{0}, 0)
+	return storage, nil
+}
+
+// Retrieve the access token using an auth token
+func (storage *FileFabricStorage) getAccessToken() (error) {
+
+    formData := url.Values { "authtoken": {storage.authToken},}
+	readCloser, _, _, err := storage.sendRequest(0, http.MethodPost, storage.getAPIURL("getTokenByAuthToken"), nil, formData)
+	if err != nil {
+		return err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+    var output struct {
+		FileFabricResponse
+        Token string `xml:"token"`
+    }
+
+    err = xml.NewDecoder(readCloser).Decode(&output)
+    if err != nil {
+        return err
+    }
+
+	err = checkFileFabricResponse(output.FileFabricResponse, "request the access token")
+	if err != nil {
+		return err
+	}
+
+	storage.accessToken = output.Token
+    return nil
+}
+
+// Determine if we should retry based on the number of retries given by 'retry' and if so calculate the delay with exponential backoff
+func (storage *FileFabricStorage) shouldRetry(retry int, messageFormat string, messageArguments ...interface{}) bool {
+	message := fmt.Sprintf(messageFormat, messageArguments...)
+
+	if retry >= storage.maxRetries {
+		LOG_WARN("FILEFABRIC_REQUEST", "%s", message)
+		return false
+	}
+	backoff := 1 << uint(retry)
+	if backoff > 60 {
+		backoff = 60
+	}
+	delay := rand.Intn(backoff*500) + backoff*500
+	LOG_INFO("FILEFABRIC_RETRY", "%s; retrying after %.1f seconds", message, float32(delay) / 1000.0)
+	time.Sleep(time.Duration(delay) * time.Millisecond)
+	return true
+}
+
+// Send a request to the server
+func (storage *FileFabricStorage) sendRequest(threadIndex int, method string, requestURL string, requestHeaders map[string]string, input interface{}) ( io.ReadCloser, http.Header, int64, error) {
+
+	var response *http.Response
+
+	for retries := 0; ; retries++ {
+		var inputReader io.Reader
+
+		switch input.(type) {
+		case url.Values:
+			values := input.(url.Values)
+			inputReader = strings.NewReader(values.Encode())
+			if requestHeaders == nil {
+				requestHeaders = make(map[string]string)
+			}
+			requestHeaders["Content-Type"] = "application/x-www-form-urlencoded"
+		case *RateLimitedReader:
+			rateLimitedReader := input.(*RateLimitedReader)
+			rateLimitedReader.Reset()
+			inputReader = rateLimitedReader
+		default:
+			LOG_FATAL("FILEFABRIC_REQUEST", "Input type is not supported")
+			return nil, nil, 0, fmt.Errorf("Input type is not supported")
+		}
+
+		request, err := http.NewRequest(method, requestURL, inputReader)
+		if err != nil {
+			return nil, nil, 0, err
+		}
+
+		if requestHeaders != nil {
+			for key, value := range requestHeaders {
+				request.Header.Set(key, value)
+			}
+		}
+
+		if _, ok := input.(*RateLimitedReader); ok {
+			request.ContentLength = input.(*RateLimitedReader).Length()
+		}
+
+		response, err = storage.client.Do(request)
+		if err != nil {
+			if !storage.shouldRetry(retries, "[%d] %s %s returned an error: %v", threadIndex, method, requestURL, err) {
+				return nil, nil, 0, err
+			}
+			continue
+		}
+
+		if response.StatusCode < 300 {
+			return response.Body, response.Header, response.ContentLength, nil
+		}
+
+		defer response.Body.Close()
+		defer io.Copy(ioutil.Discard, response.Body)	
+
+		var output struct {
+			Status string `xml:"status"`
+			Message string `xml:"statusmessage"`
+		}
+	
+		err = xml.NewDecoder(response.Body).Decode(&output)
+		if err != nil {
+			if !storage.shouldRetry(retries, "[%d] %s %s returned an invalid response: %v", threadIndex, method, requestURL, err) {
+				return nil, nil, 0, err
+			}
+			continue
+		}
+
+		if !storage.shouldRetry(retries, "[%d] %s %s returned status: %s, message: %s", threadIndex, method, requestURL, output.Status, output.Message) {
+			return nil, nil, 0, err
+		}
+	}
+
+}
+
+func (storage *FileFabricStorage) getAPIURL(function string) string {
+	if storage.accessToken == "" {
+		return "https://" + storage.endpoint + "/api/*/" + function + "/"
+	} else {
+		return "https://" + storage.endpoint + "/api/" + storage.accessToken + "/" + function + "/"
+	}
+}
+
+// ListFiles return the list of files and subdirectories under 'dir'.  A subdirectories returned must have a trailing '/', with
+// a size of 0.  If 'dir' is 'snapshots', only subdirectories will be returned.  If 'dir' is 'snapshots/repository_id', then only
+// files will be returned.  If 'dir' is 'chunks', the implementation can return the list either recusively or non-recusively.
+func (storage *FileFabricStorage) ListFiles(threadIndex int, dir string) (files []string, sizes []int64, err error) {
+	if dir != "" && dir[len(dir)-1] != '/' {
+		dir += "/"
+	}
+
+	dirID, _, _, err := storage.getFileInfo(threadIndex, dir)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if dirID == "" {
+		return nil, nil, nil
+	}
+
+	lastID := ""
+
+	for {
+		formData := url.Values { "marker": {lastID}, "limit": {"1000"}, "includefolders": {"n"}, "fi_pid" : {dirID}}
+		if dir == "snapshots/" {
+			formData["includefolders"] = []string{"y"}
+		}
+		if storage.testMode {
+			formData["limit"] = []string{"5"}
+		}
+
+		readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("getListOfFiles"), nil, formData)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		defer readCloser.Close()
+		defer io.Copy(ioutil.Discard, readCloser)	
+
+		var output struct {
+			FileFabricResponse
+			FileList FileFabricFileList `xml:"files"`
+			Truncated int `xml:"truncated"`
+		}
+
+		err = xml.NewDecoder(readCloser).Decode(&output)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		err = checkFileFabricResponse(output.FileFabricResponse, "list the storage directory '%s'", dir)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		if dir == "snapshots/" {
+			for _, file := range output.FileList.Files {
+				if file.Type == 1 {
+					files = append(files, file.Path + "/")
+				}
+				lastID = file.ID
+			}
+		} else {
+			for _, file := range output.FileList.Files {
+				if file.Type == 0 {
+					files = append(files, file.Path)
+					sizes = append(sizes, file.Size)
+				}
+				lastID = file.ID
+			}
+		}
+
+		if output.Truncated != 1 {
+			break
+		}
+	}
+	return files, sizes, nil
+}
+
+// getFileInfo returns the information about the file or directory at 'filePath'.
+func (storage *FileFabricStorage) getFileInfo(threadIndex int, filePath string) (fileID string, isDir bool, size int64, err error) {
+
+	formData := url.Values { "path" : {storage.storageDir + filePath}}
+
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("checkPathExists"), nil, formData)
+	if err != nil {
+		return "", false, 0, err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+	var output struct {
+		FileFabricResponse
+		File FileFabricFile `xml:"file"`
+		Exists string `xml:"exists"`
+	}
+
+	err = xml.NewDecoder(readCloser).Decode(&output)
+	if err != nil {
+		return "", false, 0, err
+	}
+
+	err = checkFileFabricResponse(output.FileFabricResponse, "get the info on '%s'", filePath)
+	if err != nil {
+		return "", false, 0, err
+	}
+
+	if output.Exists != "y" {
+		return "", false, 0, nil
+	} else {
+		if output.File.Type == 1 {
+			for filePath != "" && filePath[len(filePath)-1] == '/' {
+				filePath = filePath[:len(filePath)-1]
+			}
+			
+			storage.directoryCacheLock.Lock()
+			storage.directoryCache[filePath] = output.File.ID
+			storage.directoryCacheLock.Unlock()
+		}
+		return output.File.ID, output.File.Type == 1, output.File.Size, nil
+	}
+}
+
+// GetFileInfo returns the information about the file or directory at 'filePath'.  This is a function required by the Storage interface.
+func (storage *FileFabricStorage) GetFileInfo(threadIndex int, filePath string) (exist bool, isDir bool, size int64, err error) {
+
+	fileID := ""
+	fileID, isDir, size, err = storage.getFileInfo(threadIndex, filePath)
+	return fileID != "", isDir, size, err
+}
+
+// DeleteFile deletes the file or directory at 'filePath'.
+func (storage *FileFabricStorage) DeleteFile(threadIndex int, filePath string) (err error) {
+
+	fileID, _, _, _ := storage.getFileInfo(threadIndex, filePath)
+	if fileID == "" {
+		return nil
+	}
+
+	formData := url.Values { "fi_id" : {fileID}}
+
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("doDeleteFile"), nil, formData)
+	if err != nil {
+		return err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+	var output FileFabricResponse
+
+	err = xml.NewDecoder(readCloser).Decode(&output)
+	if err != nil {
+		return err
+	}
+
+	err = checkFileFabricResponse(output, "delete file '%s'", filePath)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// MoveFile renames the file.
+func (storage *FileFabricStorage) MoveFile(threadIndex int, from string, to string) (err error) {
+	fileID, _, _, _ := storage.getFileInfo(threadIndex, from)
+	if fileID == "" {
+		return nil
+	}
+
+	formData := url.Values { "fi_id" : {fileID}, "fi_name": {filepath.Base(to)},}
+
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("doRenameFile"), nil, formData)
+	if err != nil {
+		return err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+	var output FileFabricResponse
+
+	err = xml.NewDecoder(readCloser).Decode(&output)
+	if err != nil {
+		return err
+	}
+
+	err = checkFileFabricResponse(output, "rename file '%s' to '%s'", from, to)
+	if err != nil {
+		return err
+	}
+	
+	return nil
+}
+
+// createParentDirectory creates the parent directory if it doesn't exist in the cache.
+func (storage *FileFabricStorage) createParentDirectory(threadIndex int, dir string) (parentID string, err error) {
+
+	found := strings.LastIndex(dir, "/")
+	if found == -1 {
+		return storage.storageDirID, nil
+	}
+	parent := dir[:found]
+
+	storage.directoryCacheLock.Lock()
+	parentID = storage.directoryCache[parent]
+	storage.directoryCacheLock.Unlock()
+
+	if parentID != "" {
+		return parentID, nil
+	}
+
+	parentID, err = storage.createDirectory(threadIndex, parent)
+	if err != nil {
+		if err == errFileFabricDirectoryExists {
+		    var isDir bool
+			parentID, isDir, _, err = storage.getFileInfo(threadIndex, parent)
+			if err != nil {
+				return "", err
+			}
+			if isDir == false {
+				return "", fmt.Errorf("'%s' in the storage is a file", parent)
+			}
+			storage.directoryCacheLock.Lock()
+			storage.directoryCache[parent] = parentID
+			storage.directoryCacheLock.Unlock()
+			return parentID, nil
+		} else {
+			return "", err
+		}
+	}
+	return parentID, nil
+}
+
+// createDirectory creates a new directory.
+func (storage *FileFabricStorage) createDirectory(threadIndex int, dir string) (dirID string, err error) {
+	for dir != "" && dir[len(dir)-1] == '/' {
+		dir = dir[:len(dir)-1]
+	}
+
+	parentID, err := storage.createParentDirectory(threadIndex, dir)
+	if err != nil {
+		return "", err
+	}
+
+	formData := url.Values { "fi_name": {filepath.Base(dir)}, "fi_pid" : {parentID}}
+
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("doCreateNewFolder"), nil, formData)
+	if err != nil {
+		return "", err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+	var output struct {
+		FileFabricResponse
+		File FileFabricFile `xml:"file"`
+	}
+
+	err = xml.NewDecoder(readCloser).Decode(&output)
+	if err != nil {
+		return "", err
+	}
+
+	err = checkFileFabricResponse(output.FileFabricResponse, "create directory '%s'", dir)
+	if err != nil {
+		return "", err
+	}
+
+	storage.directoryCacheLock.Lock()
+	storage.directoryCache[dir] = output.File.ID
+	storage.directoryCacheLock.Unlock()
+
+	return output.File.ID, nil
+}
+
+func (storage *FileFabricStorage) CreateDirectory(threadIndex int, dir string) (err error) {
+	_, err = storage.createDirectory(threadIndex, dir)
+	if err == errFileFabricDirectoryExists {
+		return nil
+	}
+	return err
+}
+
+// DownloadFile reads the file at 'filePath' into the chunk.
+func (storage *FileFabricStorage) DownloadFile(threadIndex int, filePath string, chunk *Chunk) (err error) {
+	formData := url.Values { "fi_id" : {storage.storageDir + filePath}}
+
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("getFile"), nil, formData)
+	if err != nil {
+		return err
+	}
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+	_, err = RateLimitedCopy(chunk, readCloser, storage.DownloadRateLimit/storage.threads)
+	return err
+}
+
+// UploadFile writes 'content' to the file at 'filePath'.
+func (storage *FileFabricStorage) UploadFile(threadIndex int, filePath string, content []byte) (err error) {
+
+	parentID, err := storage.createParentDirectory(threadIndex, filePath)
+	if err != nil {
+		return err
+	}
+
+	fileName := filepath.Base(filePath)
+    requestBody := &bytes.Buffer{}
+    writer := multipart.NewWriter(requestBody)
+    part, _ := writer.CreateFormFile("file_1", fileName)
+    part.Write(content)
+
+    writer.WriteField("file_name1", fileName)
+	writer.WriteField("fi_pid", parentID)
+	writer.WriteField("fi_structtype", "g")
+    writer.Close()
+
+	headers := make(map[string]string)
+	headers["Content-Type"] = writer.FormDataContentType()
+
+	rateLimitedReader := CreateRateLimitedReader(requestBody.Bytes(), storage.UploadRateLimit/storage.threads)
+	readCloser, _, _, err := storage.sendRequest(threadIndex, http.MethodPost, storage.getAPIURL("doUploadFiles"), headers, rateLimitedReader)
+
+	defer readCloser.Close()
+	defer io.Copy(ioutil.Discard, readCloser)	
+
+	var output FileFabricResponse
+
+	err = xml.NewDecoder(readCloser).Decode(&output)
+	if err != nil {
+		return err
+	}
+
+	err = checkFileFabricResponse(output, "upload file '%s'", filePath)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// If a local snapshot cache is needed for the storage to avoid downloading/uploading chunks too often when
+// managing snapshots.
+func (storage *FileFabricStorage) IsCacheNeeded() bool { return true }
+
+// If the 'MoveFile' method is implemented.
+func (storage *FileFabricStorage) IsMoveFileImplemented() bool { return true }
+
+// If the storage can guarantee strong consistency.
+func (storage *FileFabricStorage) IsStrongConsistent() bool { return false }
+
+// If the storage supports fast listing of files names.
+func (storage *FileFabricStorage) IsFastListing() bool { return false }
+
+// Enable the test mode.
+func (storage *FileFabricStorage) EnableTestMode() { storage.testMode = true }

src/duplicacy_filereader.go

@@ -34,7 +34,7 @@ func CreateFileReader(top string, files []*Entry) *FileReader {
 	return reader
 }
 
-// NextFile switchs to the next file in the file reader.
+// NextFile switches to the next file in the file reader.
 func (reader *FileReader) NextFile() bool {
 
 	if reader.CurrentFile != nil {

src/duplicacy_filestorage.go

@@ -12,6 +12,7 @@ import (
 	"os"
 	"path"
 	"strings"
+	"syscall"
 	"time"
 )
 
@@ -165,7 +166,7 @@ func (storage *FileStorage) UploadFile(threadIndex int, filePath string, content
 			}
 		} else {
 			if !stat.IsDir() {
-				fmt.Errorf("The path %s is not a directory", dir)
+				return fmt.Errorf("The path %s is not a directory", dir)
 			}
 		}
 	}
@@ -190,7 +191,19 @@ func (storage *FileStorage) UploadFile(threadIndex int, filePath string, content
 		return err
 	}
 
-	file.Close()
+	if err = file.Sync(); err != nil {
+		pathErr, ok := err.(*os.PathError)
+		isNotSupported := ok && pathErr.Op == "sync" && pathErr.Err == syscall.ENOTSUP
+		if !isNotSupported {
+			_ = file.Close()
+			return err
+		}
+	}
+
+	err = file.Close()
+	if err != nil {
+		return err
+	}
 
 	err = os.Rename(temporaryFile, fullPath)
 	if err != nil {

src/duplicacy_gcdstorage.go

@@ -20,23 +20,27 @@ import (
 
 	"golang.org/x/net/context"
 	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/google"
 	"google.golang.org/api/drive/v3"
 	"google.golang.org/api/googleapi"
+	"google.golang.org/api/option"
 )
 
 var (
-	GCDFileMimeType = "application/octet-stream"
+	GCDFileMimeType      = "application/octet-stream"
 	GCDDirectoryMimeType = "application/vnd.google-apps.folder"
+	GCDUserDrive         = "root"
 )
 
 type GCDStorage struct {
 	StorageBase
 
 	service     *drive.Service
-	idCache     map[string]string  // only directories are saved in this cache
+	idCache     map[string]string // only directories are saved in this cache
 	idCacheLock sync.Mutex
 	backoffs    []int // desired backoff time in seconds for each thread
 	attempts    []int // number of failed attempts since last success for each thread
+	driveID     string // the ID of the shared drive or 'root' (GCDUserDrive) if the user's drive
 
 	createDirectoryLock sync.Mutex
 	isConnected         bool
@@ -78,6 +82,14 @@ func (storage *GCDStorage) shouldRetry(threadIndex int, err error) (bool, error)
 			// User Rate Limit Exceeded
 			message = e.Message
 			retry = true
+		} else if e.Code == 408 {
+			// Request timeout
+			message = e.Message
+			retry = true
+		} else if e.Code == 400 && strings.Contains(e.Message, "failedPrecondition") {
+			// Daily quota exceeded
+			message = e.Message
+			retry = true
 		} else if e.Code == 401 {
 			// Only retry on authorization error when storage has been connected before
 			if storage.isConnected {
@@ -187,7 +199,11 @@ func (storage *GCDStorage) listFiles(threadIndex int, parentID string, listFiles
 		var err error
 
 		for {
-			fileList, err = storage.service.Files.List().Q(query).Fields("nextPageToken", "files(name, mimeType, id, size)").PageToken(startToken).PageSize(maxCount).Do()
+			q := storage.service.Files.List().Q(query).Fields("nextPageToken", "files(name, mimeType, id, size)").PageToken(startToken).PageSize(maxCount)
+			if storage.driveID != GCDUserDrive {
+				q = q.DriveId(storage.driveID).IncludeItemsFromAllDrives(true).Corpora("drive").SupportsAllDrives(true)
+			}
+			fileList, err = q.Do()
 			if retry, e := storage.shouldRetry(threadIndex, err); e == nil && !retry {
 				break
 			} else if retry {
@@ -215,7 +231,11 @@ func (storage *GCDStorage) listByName(threadIndex int, parentID string, name str
 
 	for {
 		query := "name = '" + name + "' and '" + parentID + "' in parents and trashed = false "
-		fileList, err = storage.service.Files.List().Q(query).Fields("files(name, mimeType, id, size)").Do()
+		q := storage.service.Files.List().Q(query).Fields("files(name, mimeType, id, size)")
+		if storage.driveID != GCDUserDrive {
+			q = q.DriveId(storage.driveID).IncludeItemsFromAllDrives(true).Corpora("drive").SupportsAllDrives(true)
+		}
+		fileList, err = q.Do()
 
 		if retry, e := storage.shouldRetry(threadIndex, err); e == nil && !retry {
 			break
@@ -244,7 +264,7 @@ func (storage *GCDStorage) getIDFromPath(threadIndex int, filePath string, creat
 		return fileID, nil
 	}
 
-	fileID := "root"
+	fileID := storage.driveID
 
 	if rootID, ok := storage.findPathID(""); ok {
 		fileID = rootID
@@ -291,7 +311,7 @@ func (storage *GCDStorage) getIDFromPath(threadIndex int, filePath string, creat
 		} else if isDir {
 			storage.savePathID(current, fileID)
 		}
-		if i != len(names) - 1 && !isDir {
+		if i != len(names)-1 && !isDir {
 			return "", fmt.Errorf("Path '%s' is not a directory", current)
 		}
 	}
@@ -299,37 +319,85 @@ func (storage *GCDStorage) getIDFromPath(threadIndex int, filePath string, creat
 }
 
 // CreateGCDStorage creates a GCD storage object.
-func CreateGCDStorage(tokenFile string, storagePath string, threads int) (storage *GCDStorage, err error) {
+func CreateGCDStorage(tokenFile string, driveID string, storagePath string, threads int) (storage *GCDStorage, err error) {
+
+	ctx := context.Background()
 
 	description, err := ioutil.ReadFile(tokenFile)
 	if err != nil {
 		return nil, err
 	}
 
-	gcdConfig := &GCDConfig{}
-	if err := json.Unmarshal(description, gcdConfig); err != nil {
-		return nil, err
-	}
+	var object map[string]interface{}
 
-	oauth2Config := oauth2.Config{
-		ClientID:     gcdConfig.ClientID,
-		ClientSecret: gcdConfig.ClientSecret,
-		Endpoint:     gcdConfig.Endpoint,
-	}
-
-	authClient := oauth2Config.Client(context.Background(), &gcdConfig.Token)
-
-	service, err := drive.New(authClient)
+	err = json.Unmarshal(description, &object)
 	if err != nil {
 		return nil, err
 	}
 
+	isServiceAccount := false
+	if value, ok := object["type"]; ok {
+		if authType, ok := value.(string); ok && authType == "service_account" {
+			isServiceAccount = true
+		}
+	}
+
+	var tokenSource oauth2.TokenSource
+
+	if isServiceAccount {
+		config, err := google.JWTConfigFromJSON(description, drive.DriveScope)
+		if err != nil {
+			return nil, err
+		}
+		tokenSource = config.TokenSource(ctx)
+	} else {
+		gcdConfig := &GCDConfig{}
+		if err := json.Unmarshal(description, gcdConfig); err != nil {
+			return nil, err
+		}
+
+		config := oauth2.Config{
+			ClientID:     gcdConfig.ClientID,
+			ClientSecret: gcdConfig.ClientSecret,
+			Endpoint:     gcdConfig.Endpoint,
+		}
+		tokenSource = config.TokenSource(ctx, &gcdConfig.Token)
+	}
+
+	service, err := drive.NewService(ctx, option.WithTokenSource(tokenSource))
+	if err != nil {
+		return nil, err
+	}
+
+	if len(driveID) == 0 {
+		driveID = GCDUserDrive
+	} else {
+		driveList, err := drive.NewTeamdrivesService(service).List().Do()
+		if err != nil {
+			return nil, fmt.Errorf("Failed to look up the drive id: %v", err)
+		}
+
+		found := false
+		for _, teamDrive := range driveList.TeamDrives {
+			if teamDrive.Id == driveID || teamDrive.Name == driveID {
+				driveID = teamDrive.Id
+				found = true
+				break
+			}
+		}
+
+		if !found {
+			return nil, fmt.Errorf("%s is not the id or name of a shared drive", driveID)
+		}
+	}
+
 	storage = &GCDStorage{
 		service:         service,
 		numberOfThreads: threads,
 		idCache:         make(map[string]string),
 		backoffs:        make([]int, threads),
 		attempts:        make([]int, threads),
+		driveID:         driveID,
 	}
 
 	for i := range storage.backoffs {
@@ -337,6 +405,7 @@ func CreateGCDStorage(tokenFile string, storagePath string, threads int) (storag
 		storage.attempts[i] = 0
 	}
 
+	storage.savePathID("", driveID)
 	storagePathID, err := storage.getIDFromPath(0, storagePath, true)
 	if err != nil {
 		return nil, err
@@ -386,11 +455,11 @@ func (storage *GCDStorage) ListFiles(threadIndex int, dir string) ([]string, []i
 		subDirs := []string{}
 
 		for _, file := range files {
-			storage.savePathID("snapshots/" + file.Name, file.Id)
-			subDirs = append(subDirs, file.Name + "/")
+			storage.savePathID("snapshots/"+file.Name, file.Id)
+			subDirs = append(subDirs, file.Name+"/")
 		}
 		return subDirs, nil, nil
-	} else if strings.HasPrefix(dir, "snapshots/") {
+	} else if strings.HasPrefix(dir, "snapshots/") || strings.HasPrefix(dir, "benchmark") {
 		pathID, err := storage.getIDFromPath(threadIndex, dir, false)
 		if err != nil {
 			return nil, nil, err
@@ -411,39 +480,76 @@ func (storage *GCDStorage) ListFiles(threadIndex int, dir string) ([]string, []i
 		}
 		return files, nil, nil
 	} else {
-		files := []string{}
-		sizes := []int64{}
+		lock := sync.Mutex {}
+		allFiles := []string{}
+		allSizes := []int64{}
+
+		errorChannel := make(chan error)
+		directoryChannel := make(chan string)
+		activeWorkers := 0
 
 		parents := []string{"chunks", "fossils"}
-		for i := 0; i < len(parents); i++ {
-			parent := parents[i]
-			pathID, ok := storage.findPathID(parent)
-			if !ok {
-				continue
-			}
-			entries, err := storage.listFiles(threadIndex, pathID, true, true)
-			if err != nil {
-				return nil, nil, err
-			}
-			for _, entry := range entries {
-				if entry.MimeType != GCDDirectoryMimeType {
-					name := entry.Name
-					if strings.HasPrefix(parent, "fossils") {
-						name = parent + "/" + name + ".fsl"
-						name = name[len("fossils/"):]
-					} else {
-						name = parent + "/" + name
-						name = name[len("chunks/"):]
+		for len(parents) > 0 || activeWorkers > 0 {
+
+			if len(parents) > 0 && activeWorkers < storage.numberOfThreads {
+				parent := parents[0]
+				parents = parents[1:]
+				activeWorkers++
+				go func(parent string) {
+					pathID, ok := storage.findPathID(parent)
+					if !ok {
+						return
+					}
+					entries, err := storage.listFiles(threadIndex, pathID, true, true)
+					if err != nil {
+						errorChannel <- err
+						return
+					}
+
+					LOG_DEBUG("GCD_STORAGE", "Listing %s; %d items returned", parent, len(entries))
+
+					files := []string {}
+					sizes := []int64 {}
+					for _, entry := range entries {
+						if entry.MimeType != GCDDirectoryMimeType {
+							name := entry.Name
+							if strings.HasPrefix(parent, "fossils") {
+								name = parent + "/" + name + ".fsl"
+								name = name[len("fossils/"):]
+							} else {
+								name = parent + "/" + name
+								name = name[len("chunks/"):]
+							}
+							files = append(files, name)
+							sizes = append(sizes, entry.Size)
+						} else {
+							directoryChannel <- parent+"/"+entry.Name
+							storage.savePathID(parent+"/"+entry.Name, entry.Id)
+						}
+					}
+					lock.Lock()
+					allFiles = append(allFiles, files...)
+					allSizes = append(allSizes, sizes...)
+					lock.Unlock()
+					directoryChannel <- ""
+				} (parent)
+			}
+
+			if activeWorkers > 0 {
+				select {
+				case err := <- errorChannel:
+					return nil, nil, err
+				case directory := <- directoryChannel:
+					if directory == "" {
+						activeWorkers--
+					} else {
+						parents = append(parents, directory)
 					}
-					files = append(files, name)
-					sizes = append(sizes, entry.Size)
-				} else {
-					parents = append(parents, parent+ "/" + entry.Name)
-					storage.savePathID(parent + "/" + entry.Name, entry.Id)
 				}
 			}
 		}
-		return files, sizes, nil
+
+		return allFiles, allSizes, nil
 	}
 
 }
@@ -458,7 +564,7 @@ func (storage *GCDStorage) DeleteFile(threadIndex int, filePath string) (err err
 	}
 
 	for {
-		err = storage.service.Files.Delete(fileID).Fields("id").Do()
+		err = storage.service.Files.Delete(fileID).SupportsAllDrives(true).Fields("id").Do()
 		if retry, err := storage.shouldRetry(threadIndex, err); err == nil && !retry {
 			storage.deletePathID(filePath)
 			return nil
@@ -504,7 +610,7 @@ func (storage *GCDStorage) MoveFile(threadIndex int, from string, to string) (er
 	}
 
 	for {
-		_, err = storage.service.Files.Update(fileID, nil).AddParents(toParentID).RemoveParents(fromParentID).Do()
+		_, err = storage.service.Files.Update(fileID, nil).SupportsAllDrives(true).AddParents(toParentID).RemoveParents(fromParentID).Do()
 		if retry, err := storage.shouldRetry(threadIndex, err); err == nil && !retry {
 			break
 		} else if retry {
@@ -555,7 +661,7 @@ func (storage *GCDStorage) CreateDirectory(threadIndex int, dir string) (err err
 			Parents:  []string{parentID},
 		}
 
-		file, err = storage.service.Files.Create(file).Fields("id").Do()
+		file, err = storage.service.Files.Create(file).SupportsAllDrives(true).Fields("id").Do()
 		if retry, err := storage.shouldRetry(threadIndex, err); err == nil && !retry {
 			break
 		} else {
@@ -624,13 +730,22 @@ func (storage *GCDStorage) DownloadFile(threadIndex int, filePath string, chunk
 	var response *http.Response
 
 	for {
-		response, err = storage.service.Files.Get(fileID).Download()
-		if retry, err := storage.shouldRetry(threadIndex, err); err == nil && !retry {
+		// AcknowledgeAbuse(true) lets the download proceed even if GCD thinks that it contains malware.
+		// TODO: Should this prompt the user or log a warning?
+		req := storage.service.Files.Get(fileID).SupportsAllDrives(true)
+		if e, ok := err.(*googleapi.Error); ok {
+			if strings.Contains(err.Error(), "cannotDownloadAbusiveFile") || len(e.Errors) > 0 && e.Errors[0].Reason == "cannotDownloadAbusiveFile" {
+				LOG_WARN("GCD_STORAGE", "%s is marked as abusive, will download anyway.", filePath)
+				req = req.AcknowledgeAbuse(true)
+			}
+		}
+		response, err = req.Download()
+		if retry, retry_err := storage.shouldRetry(threadIndex, err); retry_err == nil && !retry {
 			break
 		} else if retry {
 			continue
 		} else {
-			return err
+			return retry_err
 		}
 	}
 
@@ -663,7 +778,7 @@ func (storage *GCDStorage) UploadFile(threadIndex int, filePath string, content
 
 	for {
 		reader := CreateRateLimitedReader(content, storage.UploadRateLimit/storage.numberOfThreads)
-		_, err = storage.service.Files.Create(file).Media(reader).Fields("id").Do()
+		_, err = storage.service.Files.Create(file).SupportsAllDrives(true).Media(reader).Fields("id").Do()
 		if retry, err := storage.shouldRetry(threadIndex, err); err == nil && !retry {
 			break
 		} else if retry {

src/duplicacy_hubicstorage.go

@@ -113,7 +113,7 @@ func (storage *HubicStorage) ListFiles(threadIndex int, dir string) ([]string, [
 
 		for _, entry := range entries {
 			if entry.Type == "application/directory" {
-				files = append(files,  entry.Name + "/")
+				files = append(files, entry.Name+"/")
 				sizes = append(sizes, 0)
 			} else {
 				files = append(files, entry.Name)

src/duplicacy_keyring_windows.go

@@ -136,6 +136,16 @@ func keyringSet(key string, value string) bool {
 	if value == "" {
 		keyring[key] = nil
 	} else {
+
+		// Check if the value to be set is the same as the existing one
+		existingEncryptedValue := keyring[key]
+		if len(existingEncryptedValue) > 0 {
+			existingValue, err := keyringDecrypt(existingEncryptedValue)
+			if err == nil && string(existingValue) == value {
+				return true
+			}
+		}
+
 		encryptedValue, err := keyringEncrypt([]byte(value))
 		if err != nil {
 			LOG_DEBUG("KEYRING_ENCRYPT", "Failed to encrypt the value: %v", err)

src/duplicacy_log.go

@@ -7,10 +7,12 @@ package duplicacy
 import (
 	"fmt"
 	"os"
+	"log"
 	"runtime/debug"
 	"sync"
 	"testing"
 	"time"
+	"regexp"
 )
 
 const (
@@ -43,6 +45,13 @@ func setTestingT(t *testing.T) {
 	testingT = t
 }
 
+// Contains the ids of logs that won't be displayed
+var suppressedLogs map[string]bool = map[string]bool{}
+
+func SuppressLog(id string) {
+	suppressedLogs[id] = true
+}
+
 func getLevelName(level int) string {
 	switch level {
 	case DEBUG:
@@ -129,7 +138,7 @@ func logf(level int, logID string, format string, v ...interface{}) {
 	// fmt.Printf("%s %s %s %s\n", now.Format("2006-01-02 15:04:05.000"), getLevelName(level), logID, message)
 
 	if testingT != nil {
-		if level < WARN {
+		if level <= WARN {
 			if level >= loggingLevel {
 				testingT.Logf("%s %s %s %s\n",
 					now.Format("2006-01-02 15:04:05.000"), getLevelName(level), logID, message)
@@ -143,6 +152,12 @@ func logf(level int, logID string, format string, v ...interface{}) {
 		defer logMutex.Unlock()
 
 		if level >= loggingLevel {
+			if level <= ERROR && len(suppressedLogs) > 0 {
+				if _, found := suppressedLogs[logID]; found {
+					return
+				}
+			}
+
 			if printLogHeader {
 				fmt.Printf("%s %s %s %s\n",
 					now.Format("2006-01-02 15:04:05.000"), getLevelName(level), logID, message)
@@ -161,6 +176,32 @@ func logf(level int, logID string, format string, v ...interface{}) {
 	}
 }
 
+// Set up logging for libraries that Duplicacy depends on.  They can call 'log.Printf("[ID] message")'
+// to produce logs in Duplicacy's format
+type Logger struct {
+	formatRegex *regexp.Regexp
+}
+
+func (logger *Logger) Write(line []byte) (n int, err error) {
+	n = len(line)
+	for len(line) > 0 && line[len(line) - 1] == '\n' {
+		line = line[:len(line) - 1]
+	}
+	matched := logger.formatRegex.FindStringSubmatch(string(line))
+	if matched != nil {
+		LOG_INFO(matched[1], "%s", matched[2])
+	} else {
+		LOG_INFO("LOG_DEFAULT", "%s", line)
+	}
+
+    return
+}
+
+func init() {
+	log.SetFlags(0)
+	log.SetOutput(&Logger{ formatRegex: regexp.MustCompile(`^\[(.+)\]\s*(.+)`) })
+}
+
 const (
 	duplicacyExitCode = 100
 	otherExitCode     = 101

src/duplicacy_oneclient.go

@@ -15,6 +15,7 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"path/filepath"
 
 	"golang.org/x/oauth2"
 )
@@ -32,9 +33,6 @@ type OneDriveErrorResponse struct {
 	Error OneDriveError `json:"error"`
 }
 
-var OneDriveRefreshTokenURL = "https://duplicacy.com/one_refresh"
-var OneDriveAPIURL = "https://api.onedrive.com/v1.0"
-
 type OneDriveClient struct {
 	HTTPClient *http.Client
 
@@ -44,9 +42,13 @@ type OneDriveClient struct {
 
 	IsConnected bool
 	TestMode    bool
+
+	IsBusiness bool
+	RefreshTokenURL string
+	APIURL string
 }
 
-func NewOneDriveClient(tokenFile string) (*OneDriveClient, error) {
+func NewOneDriveClient(tokenFile string, isBusiness bool) (*OneDriveClient, error) {
 
 	description, err := ioutil.ReadFile(tokenFile)
 	if err != nil {
@@ -63,6 +65,15 @@ func NewOneDriveClient(tokenFile string) (*OneDriveClient, error) {
 		TokenFile:  tokenFile,
 		Token:      token,
 		TokenLock:  &sync.Mutex{},
+		IsBusiness: isBusiness,
+	}
+
+	if isBusiness {
+		client.RefreshTokenURL = "https://duplicacy.com/odb_refresh"
+		client.APIURL = "https://graph.microsoft.com/v1.0/me"
+	} else {
+		client.RefreshTokenURL = "https://duplicacy.com/one_refresh"
+		client.APIURL = "https://api.onedrive.com/v1.0"
 	}
 
 	client.RefreshToken(false)
@@ -106,9 +117,10 @@ func (client *OneDriveClient) call(url string, method string, input interface{},
 
 		if reader, ok := inputReader.(*RateLimitedReader); ok {
 			request.ContentLength = reader.Length()
+			request.Header.Set("Content-Range", fmt.Sprintf("bytes 0-%d/%d", reader.Length() - 1, reader.Length()))
 		}
 
-		if url != OneDriveRefreshTokenURL {
+		if url != client.RefreshTokenURL {
 			client.TokenLock.Lock()
 			request.Header.Set("Authorization", "Bearer "+client.Token.AccessToken)
 			client.TokenLock.Unlock()
@@ -152,7 +164,7 @@ func (client *OneDriveClient) call(url string, method string, input interface{},
 
 		if response.StatusCode == 401 {
 
-			if url == OneDriveRefreshTokenURL {
+			if url == client.RefreshTokenURL {
 				return nil, 0, OneDriveError{Status: response.StatusCode, Message: "Authorization error when refreshing token"}
 			}
 
@@ -161,6 +173,8 @@ func (client *OneDriveClient) call(url string, method string, input interface{},
 				return nil, 0, err
 			}
 			continue
+		} else if response.StatusCode == 409 {
+			return nil, 0, OneDriveError{Status: response.StatusCode, Message: "Conflict"}
 		} else if response.StatusCode > 401 && response.StatusCode != 404 {
 			retryAfter := time.Duration(rand.Float32() * 1000.0 * float32(backoff))
 			LOG_INFO("ONEDRIVE_RETRY", "Response code: %d; retry after %d milliseconds", response.StatusCode, retryAfter)
@@ -188,7 +202,7 @@ func (client *OneDriveClient) RefreshToken(force bool) (err error) {
 		return nil
 	}
 
-	readCloser, _, err := client.call(OneDriveRefreshTokenURL, "POST", client.Token, "")
+	readCloser, _, err := client.call(client.RefreshTokenURL, "POST", client.Token, "")
 	if err != nil {
 		return fmt.Errorf("failed to refresh the access token: %v", err)
 	}
@@ -228,9 +242,9 @@ func (client *OneDriveClient) ListEntries(path string) ([]OneDriveEntry, error)
 
 	entries := []OneDriveEntry{}
 
-	url := OneDriveAPIURL + "/drive/root:/" + path + ":/children"
+	url := client.APIURL + "/drive/root:/" + path + ":/children"
 	if path == "" {
-		url = OneDriveAPIURL + "/drive/root/children"
+		url = client.APIURL + "/drive/root/children"
 	}
 	if client.TestMode {
 		url += "?top=8"
@@ -266,7 +280,7 @@ func (client *OneDriveClient) ListEntries(path string) ([]OneDriveEntry, error)
 
 func (client *OneDriveClient) GetFileInfo(path string) (string, bool, int64, error) {
 
-	url := OneDriveAPIURL + "/drive/root:/" + path
+	url := client.APIURL + "/drive/root:/" + path
 	url += "?select=id,name,size,folder"
 
 	readCloser, _, err := client.call(url, "GET", 0, "")
@@ -291,28 +305,95 @@ func (client *OneDriveClient) GetFileInfo(path string) (string, bool, int64, err
 
 func (client *OneDriveClient) DownloadFile(path string) (io.ReadCloser, int64, error) {
 
-	url := OneDriveAPIURL + "/drive/items/root:/" + path + ":/content"
+	url := client.APIURL + "/drive/items/root:/" + path + ":/content"
 
 	return client.call(url, "GET", 0, "")
 }
 
 func (client *OneDriveClient) UploadFile(path string, content []byte, rateLimit int) (err error) {
 
-	url := OneDriveAPIURL + "/drive/root:/" + path + ":/content"
+	// Upload file using the simple method; this is only possible for OneDrive Personal or if the file
+	// is smaller than 4MB for OneDrive Business
+	if !client.IsBusiness || len(content) < 4 * 1024 * 1024 || (client.TestMode && rand.Int() % 2 == 0) {
+		url := client.APIURL + "/drive/root:/" + path + ":/content"
 
-	readCloser, _, err := client.call(url, "PUT", CreateRateLimitedReader(content, rateLimit), "application/octet-stream")
+		readCloser, _, err := client.call(url, "PUT", CreateRateLimitedReader(content, rateLimit), "application/octet-stream")
+		if err != nil {
+			return err
+		}
 
+		readCloser.Close()
+		return nil
+	}
+
+	// For large files, create an upload session first
+	uploadURL, err := client.CreateUploadSession(path)
 	if err != nil {
 		return err
 	}
 
+	return client.UploadFileSession(uploadURL, content, rateLimit)
+}
+
+func (client *OneDriveClient) CreateUploadSession(path string) (uploadURL string, err error) {
+
+	type CreateUploadSessionItem struct {
+		ConflictBehavior string `json:"@microsoft.graph.conflictBehavior"`
+		Name string `json:"name"`
+	}
+
+	input := map[string]interface{} {
+		"item": CreateUploadSessionItem {
+			ConflictBehavior: "replace",
+			Name: filepath.Base(path),
+		},
+	}
+
+	readCloser, _, err := client.call(client.APIURL + "/drive/root:/" + path + ":/createUploadSession", "POST", input, "application/json")
+	if err != nil {
+		return "", err
+	}
+
+	type CreateUploadSessionOutput struct {
+		UploadURL string `json:"uploadUrl"`
+	}
+
+	output := &CreateUploadSessionOutput{}
+
+	if err = json.NewDecoder(readCloser).Decode(&output); err != nil {
+		return "", err
+	}
+
+	readCloser.Close()
+	return output.UploadURL, nil
+}
+
+func (client *OneDriveClient) UploadFileSession(uploadURL string, content []byte, rateLimit int) (err error) {
+
+	readCloser, _, err := client.call(uploadURL, "PUT", CreateRateLimitedReader(content, rateLimit), "")
+	if err != nil {
+		return err
+	}
+	type UploadFileSessionOutput struct {
+		Size int `json:"size"`
+	}
+	output := &UploadFileSessionOutput{}
+
+	if err = json.NewDecoder(readCloser).Decode(&output); err != nil {
+		return fmt.Errorf("Failed to complete the file upload session: %v", err)
+	}
+
+	if output.Size != len(content) {
+		return fmt.Errorf("Uploaded %d bytes out of %d bytes", output.Size, len(content))
+	}
+
 	readCloser.Close()
 	return nil
 }
 
 func (client *OneDriveClient) DeleteFile(path string) error {
 
-	url := OneDriveAPIURL + "/drive/root:/" + path
+	url := client.APIURL + "/drive/root:/" + path
 
 	readCloser, _, err := client.call(url, "DELETE", 0, "")
 	if err != nil {
@@ -325,7 +406,7 @@ func (client *OneDriveClient) DeleteFile(path string) error {
 
 func (client *OneDriveClient) MoveFile(path string, parent string) error {
 
-	url := OneDriveAPIURL + "/drive/root:/" + path
+	url := client.APIURL + "/drive/root:/" + path
 
 	parentReference := make(map[string]string)
 	parentReference["path"] = "/drive/root:/" + parent
@@ -335,6 +416,20 @@ func (client *OneDriveClient) MoveFile(path string, parent string) error {
 
 	readCloser, _, err := client.call(url, "PATCH", parameters, "application/json")
 	if err != nil {
+		if e, ok := err.(OneDriveError); ok && e.Status == 400 {
+			// The destination directory doesn't exist; trying to create it...
+			dir := filepath.Dir(parent)
+			if dir == "." {
+				dir = ""
+			}
+			client.CreateDirectory(dir, filepath.Base(parent))
+			readCloser, _, err = client.call(url, "PATCH", parameters, "application/json")
+			if err != nil {
+				return nil
+			}
+
+		}
+
 		return err
 	}
 
@@ -344,24 +439,29 @@ func (client *OneDriveClient) MoveFile(path string, parent string) error {
 
 func (client *OneDriveClient) CreateDirectory(path string, name string) error {
 
-	url := OneDriveAPIURL + "/root/children"
+	url := client.APIURL + "/root/children"
 
 	if path != "" {
 
-		parentID, isDir, _, err := client.GetFileInfo(path)
+		pathID, isDir, _, err := client.GetFileInfo(path)
 		if err != nil {
 			return err
 		}
 
-		if parentID == "" {
-			return fmt.Errorf("The path '%s' does not exist", path)
+		if pathID == "" {
+			dir := filepath.Dir(path)
+			if dir != "." {
+				// The parent directory doesn't exist; trying to create it...
+				client.CreateDirectory(dir, filepath.Base(path))
+				isDir = true
+			}
 		}
 
 		if !isDir {
 			return fmt.Errorf("The path '%s' is not a directory", path)
 		}
 
-		url = OneDriveAPIURL + "/drive/items/" + parentID + "/children"
+		url = client.APIURL + "/drive/root:/" + path + ":/children"
 	}
 
 	parameters := make(map[string]interface{})
@@ -370,6 +470,11 @@ func (client *OneDriveClient) CreateDirectory(path string, name string) error {
 
 	readCloser, _, err := client.call(url, "POST", parameters, "application/json")
 	if err != nil {
+		if e, ok := err.(OneDriveError); ok && e.Status == 409 {
+			// This error usually means the directory already exists
+			LOG_TRACE("ONEDRIVE_MKDIR", "The directory '%s/%s' already exists", path, name)
+			return nil
+		}
 		return err
 	}
 

src/duplicacy_oneclient_test.go

@@ -17,7 +17,7 @@ import (
 
 func TestOneDriveClient(t *testing.T) {
 
-	oneDriveClient, err := NewOneDriveClient("one-token.json")
+	oneDriveClient, err := NewOneDriveClient("one-token.json", false)
 	if err != nil {
 		t.Errorf("Failed to create the OneDrive client: %v", err)
 		return

src/duplicacy_onestorage.go

@@ -19,13 +19,13 @@ type OneDriveStorage struct {
 }
 
 // CreateOneDriveStorage creates an OneDrive storage object.
-func CreateOneDriveStorage(tokenFile string, storagePath string, threads int) (storage *OneDriveStorage, err error) {
+func CreateOneDriveStorage(tokenFile string, isBusiness bool, storagePath string, threads int) (storage *OneDriveStorage, err error) {
 
 	for len(storagePath) > 0 && storagePath[len(storagePath)-1] == '/' {
 		storagePath = storagePath[:len(storagePath)-1]
 	}
 
-	client, err := NewOneDriveClient(tokenFile)
+	client, err := NewOneDriveClient(tokenFile, isBusiness)
 	if err != nil {
 		return nil, err
 	}
@@ -80,6 +80,7 @@ func (storage *OneDriveStorage) convertFilePath(filePath string) string {
 
 // ListFiles return the list of files and subdirectories under 'dir' (non-recursively)
 func (storage *OneDriveStorage) ListFiles(threadIndex int, dir string) ([]string, []int64, error) {
+
 	for len(dir) > 0 && dir[len(dir)-1] == '/' {
 		dir = dir[:len(dir)-1]
 	}
@@ -97,7 +98,7 @@ func (storage *OneDriveStorage) ListFiles(threadIndex int, dir string) ([]string
 			}
 		}
 		return subDirs, nil, nil
-	} else if strings.HasPrefix(dir, "snapshots/") {
+	} else if strings.HasPrefix(dir, "snapshots/") || strings.HasPrefix(dir, "benchmark") {
 		entries, err := storage.client.ListEntries(storage.storageDir + "/" + dir)
 		if err != nil {
 			return nil, nil, err

src/duplicacy_preference.go

@@ -17,12 +17,15 @@ import (
 type Preference struct {
 	Name              string            `json:"name"`
 	SnapshotID        string            `json:"id"`
+	RepositoryPath    string            `json:"repository"`
 	StorageURL        string            `json:"storage"`
 	Encrypted         bool              `json:"encrypted"`
 	BackupProhibited  bool              `json:"no_backup"`
 	RestoreProhibited bool              `json:"no_restore"`
 	DoNotSavePassword bool              `json:"no_save_password"`
+	NobackupFile      string            `json:"nobackup_file"`
 	Keys              map[string]string `json:"keys"`
+	FiltersFile           string        `json:"filters"`
 }
 
 var preferencePath string

src/duplicacy_s3storage.go

@@ -210,7 +210,7 @@ func (storage *S3Storage) DownloadFile(threadIndex int, filePath string, chunk *
 
 	defer output.Body.Close()
 
-	_, err = RateLimitedCopy(chunk, output.Body, storage.DownloadRateLimit/len(storage.bucket))
+	_, err = RateLimitedCopy(chunk, output.Body, storage.DownloadRateLimit/storage.numberOfThreads)
 	return err
 
 }
@@ -225,7 +225,7 @@ func (storage *S3Storage) UploadFile(threadIndex int, filePath string, content [
 			Bucket:      aws.String(storage.bucket),
 			Key:         aws.String(storage.storageDir + filePath),
 			ACL:         aws.String(s3.ObjectCannedACLPrivate),
-			Body:        CreateRateLimitedReader(content, storage.UploadRateLimit/len(storage.bucket)),
+			Body:        CreateRateLimitedReader(content, storage.UploadRateLimit/storage.numberOfThreads),
 			ContentType: aws.String("application/duplicacy"),
 		}
 
@@ -237,8 +237,6 @@ func (storage *S3Storage) UploadFile(threadIndex int, filePath string, content [
 		LOG_INFO("S3_RETRY", "Retrying on %s: %v", reflect.TypeOf(err), err)
 		attempts += 1
 	}
-
-	return err
 }
 
 // If a local snapshot cache is needed for the storage to avoid downloading/uploading chunks too often when

src/duplicacy_sftpstorage.go

@@ -14,6 +14,7 @@ import (
 	"runtime"
 	"strings"
 	"time"
+	"sync"
 
 	"github.com/pkg/sftp"
 	"golang.org/x/crypto/ssh"
@@ -23,9 +24,13 @@ type SFTPStorage struct {
 	StorageBase
 
 	client          *sftp.Client
+	clientLock      sync.Mutex
 	minimumNesting  int // The minimum level of directories to dive into before searching for the chunk file.
 	storageDir      string
 	numberOfThreads int
+	numberOfTries   int
+	serverAddress   string
+	sftpConfig      *ssh.ClientConfig
 }
 
 func CreateSFTPStorageWithPassword(server string, port int, username string, storageDir string,
@@ -38,10 +43,10 @@ func CreateSFTPStorageWithPassword(server string, port int, username string, sto
 		return nil
 	}
 
-	return CreateSFTPStorage(server, port, username, storageDir, minimumNesting, authMethods, hostKeyCallback, threads)
+	return CreateSFTPStorage(false, server, port, username, storageDir, minimumNesting, authMethods, hostKeyCallback, threads)
 }
 
-func CreateSFTPStorage(server string, port int, username string, storageDir string, minimumNesting int,
+func CreateSFTPStorage(compatibilityMode bool, server string, port int, username string, storageDir string, minimumNesting int,
 	authMethods []ssh.AuthMethod,
 	hostKeyCallback func(hostname string, remote net.Addr,
 		key ssh.PublicKey) error, threads int) (storage *SFTPStorage, err error) {
@@ -52,8 +57,21 @@ func CreateSFTPStorage(server string, port int, username string, storageDir stri
 		HostKeyCallback: hostKeyCallback,
 	}
 
-	if server == "sftp.hidrive.strato.com" {
-		sftpConfig.Ciphers = []string{"aes128-ctr", "aes256-ctr"}
+	if compatibilityMode {
+		sftpConfig.Ciphers = []string{
+			"aes128-ctr", "aes192-ctr", "aes256-ctr",
+			"aes128-gcm@openssh.com",
+			"chacha20-poly1305@openssh.com",
+			"arcfour256", "arcfour128", "arcfour",
+			"aes128-cbc",
+			"3des-cbc",
+		}
+		sftpConfig.KeyExchanges = [] string {
+			"curve25519-sha256@libssh.org",
+			"ecdh-sha2-nistp256", "ecdh-sha2-nistp384", "ecdh-sha2-nistp521",
+			"diffie-hellman-group1-sha1", "diffie-hellman-group14-sha1",
+			"diffie-hellman-group-exchange-sha1", "diffie-hellman-group-exchange-sha256",
+		}
 	}
 
 	serverAddress := fmt.Sprintf("%s:%d", server, port)
@@ -86,6 +104,9 @@ func CreateSFTPStorage(server string, port int, username string, storageDir stri
 		storageDir:      storageDir,
 		minimumNesting:  minimumNesting,
 		numberOfThreads: threads,
+		numberOfTries:   8,
+		serverAddress:   serverAddress,
+		sftpConfig:      sftpConfig,
 	}
 
 	// Random number fo generating the temporary chunk file suffix.
@@ -99,13 +120,57 @@ func CreateSFTPStorage(server string, port int, username string, storageDir stri
 }
 
 func CloseSFTPStorage(storage *SFTPStorage) {
-	storage.client.Close()
+	if storage.client != nil {
+		storage.client.Close()
+		storage.client = nil
+	}
 }
 
+func (storage *SFTPStorage) getSFTPClient() *sftp.Client {
+	storage.clientLock.Lock()
+	defer storage.clientLock.Unlock()
+	return storage.client
+}
+
+func (storage *SFTPStorage) retry(f func () error) error {
+	delay := time.Second
+	for i := 0;; i++ {
+		err := f()
+		if err != nil && strings.Contains(err.Error(), "EOF") && i < storage.numberOfTries {
+			LOG_WARN("SFTP_RETRY", "Encountered an error (%v); retry after %d second(s)", err, delay/time.Second)
+			time.Sleep(delay)
+			delay *= 2
+
+			storage.clientLock.Lock()
+			connection, err := ssh.Dial("tcp", storage.serverAddress, storage.sftpConfig)
+			if err != nil {
+				LOG_WARN("SFT_RECONNECT", "Failed to connect to %s: %v; retrying", storage.serverAddress, err)
+				storage.clientLock.Unlock()
+				continue
+			}
+
+			client, err := sftp.NewClient(connection)
+			if err != nil {
+				LOG_WARN("SFT_RECONNECT", "Failed to create a new SFTP client to %s: %v; retrying", storage.serverAddress, err)
+				connection.Close()
+				storage.clientLock.Unlock()
+				continue
+			}
+			storage.client = client
+			storage.clientLock.Unlock()
+			continue
+		}
+		return err
+	}
+}
 // ListFiles return the list of files and subdirectories under 'file' (non-recursively)
 func (storage *SFTPStorage) ListFiles(threadIndex int, dirPath string) (files []string, sizes []int64, err error) {
 
-	entries, err := storage.client.ReadDir(path.Join(storage.storageDir, dirPath))
+	var entries []os.FileInfo
+	err = storage.retry(func() error {
+		entries, err = storage.getSFTPClient().ReadDir(path.Join(storage.storageDir, dirPath))
+		return err
+	})
 	if err != nil {
 		return nil, nil, err
 	}
@@ -126,7 +191,11 @@ func (storage *SFTPStorage) ListFiles(threadIndex int, dirPath string) (files []
 // DeleteFile deletes the file or directory at 'filePath'.
 func (storage *SFTPStorage) DeleteFile(threadIndex int, filePath string) (err error) {
 	fullPath := path.Join(storage.storageDir, filePath)
-	fileInfo, err := storage.client.Stat(fullPath)
+	var fileInfo os.FileInfo
+	err = storage.retry(func() error {
+		fileInfo, err = storage.getSFTPClient().Stat(fullPath)
+		return err
+	})
 	if err != nil {
 		if os.IsNotExist(err) {
 			LOG_TRACE("SFTP_STORAGE", "File %s has disappeared before deletion", filePath)
@@ -137,33 +206,47 @@ func (storage *SFTPStorage) DeleteFile(threadIndex int, filePath string) (err er
 	if fileInfo == nil {
 		return nil
 	}
-	return storage.client.Remove(path.Join(storage.storageDir, filePath))
+	return storage.retry(func() error { return storage.getSFTPClient().Remove(path.Join(storage.storageDir, filePath)) })
 }
 
 // MoveFile renames the file.
 func (storage *SFTPStorage) MoveFile(threadIndex int, from string, to string) (err error) {
 	toPath := path.Join(storage.storageDir, to)
-	fileInfo, err := storage.client.Stat(toPath)
+	var fileInfo os.FileInfo
+	err = storage.retry(func() error {
+		fileInfo, err = storage.getSFTPClient().Stat(toPath)
+		return err
+	})
 	if fileInfo != nil {
 		return fmt.Errorf("The destination file %s already exists", toPath)
 	}
-	return storage.client.Rename(path.Join(storage.storageDir, from),
-		path.Join(storage.storageDir, to))
+	err = storage.retry(func() error { return storage.getSFTPClient().Rename(path.Join(storage.storageDir, from),
+		path.Join(storage.storageDir, to)) })
+	return err
 }
 
 // CreateDirectory creates a new directory.
 func (storage *SFTPStorage) CreateDirectory(threadIndex int, dirPath string) (err error) {
 	fullPath := path.Join(storage.storageDir, dirPath)
-	fileInfo, err := storage.client.Stat(fullPath)
+	var fileInfo os.FileInfo
+	err = storage.retry(func() error {
+		fileInfo, err = storage.getSFTPClient().Stat(fullPath)
+		return err
+	})
 	if fileInfo != nil && fileInfo.IsDir() {
 		return nil
 	}
-	return storage.client.Mkdir(path.Join(storage.storageDir, dirPath))
+	return storage.retry(func() error { return storage.getSFTPClient().Mkdir(path.Join(storage.storageDir, dirPath)) })
 }
 
 // GetFileInfo returns the information about the file or directory at 'filePath'.
 func (storage *SFTPStorage) GetFileInfo(threadIndex int, filePath string) (exist bool, isDir bool, size int64, err error) {
-	fileInfo, err := storage.client.Stat(path.Join(storage.storageDir, filePath))
+	var fileInfo os.FileInfo
+	err = storage.retry(func() error {
+		fileInfo, err = storage.getSFTPClient().Stat(path.Join(storage.storageDir, filePath))
+		return err
+	})
+
 	if err != nil {
 		if os.IsNotExist(err) {
 			return false, false, 0, nil
@@ -181,18 +264,19 @@ func (storage *SFTPStorage) GetFileInfo(threadIndex int, filePath string) (exist
 
 // DownloadFile reads the file at 'filePath' into the chunk.
 func (storage *SFTPStorage) DownloadFile(threadIndex int, filePath string, chunk *Chunk) (err error) {
-	file, err := storage.client.Open(path.Join(storage.storageDir, filePath))
+	return storage.retry(func() error {
+		file, err := storage.getSFTPClient().Open(path.Join(storage.storageDir, filePath))
 
-	if err != nil {
-		return err
-	}
+		if err != nil {
+			return err
+		}
 
-	defer file.Close()
-	if _, err = RateLimitedCopy(chunk, file, storage.DownloadRateLimit/storage.numberOfThreads); err != nil {
-		return err
-	}
-
-	return nil
+		defer file.Close()
+		if _, err = RateLimitedCopy(chunk, file, storage.DownloadRateLimit/storage.numberOfThreads); err != nil {
+			return err
+		}
+		return nil
+	})
 }
 
 // UploadFile writes 'content' to the file at 'filePath'.
@@ -201,62 +285,57 @@ func (storage *SFTPStorage) UploadFile(threadIndex int, filePath string, content
 	fullPath := path.Join(storage.storageDir, filePath)
 
 	dirs := strings.Split(filePath, "/")
-	if len(dirs) > 1 {
-		fullDir := path.Dir(fullPath)
-		_, err := storage.client.Stat(fullDir)
-		if err != nil {
-			// The error may be caused by a non-existent fullDir, or a broken connection.  In either case,
-			// we just assume it is the former because there isn't a way to tell which is the case.
-			for i, _ := range dirs[1 : len(dirs)-1] {
-				subDir := path.Join(storage.storageDir, path.Join(dirs[0:i+2]...))
-				// We don't check the error; just keep going blindly but always store the last err
-				err = storage.client.Mkdir(subDir)
-			}
+	fullDir := path.Dir(fullPath)
+	return storage.retry(func() error {
 
-			// If there is an error creating the dirs, we check fullDir one more time, because another thread
-			// may happen to create the same fullDir ahead of this thread
-			if err != nil {
-				_, err := storage.client.Stat(fullDir)
-				if err != nil {
-					return err
+		if len(dirs) > 1 {
+			_, err := storage.getSFTPClient().Stat(fullDir)
+			if os.IsNotExist(err) {
+				for i := range dirs[1 : len(dirs)-1] {
+					subDir := path.Join(storage.storageDir, path.Join(dirs[0:i+2]...))
+					// We don't check the error; just keep going blindly
+					storage.getSFTPClient().Mkdir(subDir)
 				}
 			}
 		}
-	}
 
-	letters := "abcdefghijklmnopqrstuvwxyz"
-	suffix := make([]byte, 8)
-	for i := range suffix {
-		suffix[i] = letters[rand.Intn(len(letters))]
-	}
-
-	temporaryFile := fullPath + "." + string(suffix) + ".tmp"
-
-	file, err := storage.client.OpenFile(temporaryFile, os.O_WRONLY|os.O_CREATE|os.O_TRUNC)
-	if err != nil {
-		return err
-	}
-
-	reader := CreateRateLimitedReader(content, storage.UploadRateLimit/storage.numberOfThreads)
-	_, err = io.Copy(file, reader)
-	if err != nil {
-		file.Close()
-		return err
-	}
-	file.Close()
-
-	err = storage.client.Rename(temporaryFile, fullPath)
-	if err != nil {
-
-		if _, err = storage.client.Stat(fullPath); err == nil {
-			storage.client.Remove(temporaryFile)
-			return nil
-		} else {
-			return fmt.Errorf("Uploaded file but failed to store it at %s: %v", fullPath, err)
+		letters := "abcdefghijklmnopqrstuvwxyz"
+		suffix := make([]byte, 8)
+		for i := range suffix {
+			suffix[i] = letters[rand.Intn(len(letters))]
 		}
-	}
 
-	return nil
+		temporaryFile := fullPath + "." + string(suffix) + ".tmp"
+
+		file, err := storage.getSFTPClient().OpenFile(temporaryFile, os.O_WRONLY|os.O_CREATE|os.O_TRUNC)
+		if err != nil {
+			return err
+		}
+
+		reader := CreateRateLimitedReader(content, storage.UploadRateLimit/storage.numberOfThreads)
+		_, err = io.Copy(file, reader)
+		if err != nil {
+			file.Close()
+			return err
+		}
+
+		err = file.Close()
+		if err != nil {
+			return err
+		}
+
+		err = storage.getSFTPClient().Rename(temporaryFile, fullPath)
+		if err != nil {
+			if _, err = storage.getSFTPClient().Stat(fullPath); err == nil {
+				storage.getSFTPClient().Remove(temporaryFile)
+				return nil
+			} else {
+				return fmt.Errorf("Uploaded file but failed to store it at %s: %v", fullPath, err)
+			}
+		}
+
+		return nil
+	})
 }
 
 // If a local snapshot cache is needed for the storage to avoid downloading/uploading chunks too often when

src/duplicacy_shadowcopy.go

@@ -3,6 +3,7 @@
 // Commercial use requires per-user licenses available from https://duplicacy.com
 
 // +build !windows
+// +build !darwin
 
 package duplicacy
 

src/duplicacy_shadowcopy_darwin.go

@@ -0,0 +1,186 @@
+//
+// Shadow copy module for Mac OSX using APFS snapshot
+//
+//
+// This module copyright 2018 Adam Marcus (https://github.com/amarcu5)
+// and may be distributed under the same terms as Duplicacy.
+
+package duplicacy
+
+import (
+	"context"
+	"errors"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"regexp"
+	"strings"
+	"syscall"
+	"time"
+)
+
+var snapshotPath string
+var snapshotDate string
+
+// Converts char array to string
+func CharsToString(ca []int8) string {
+
+	len := len(ca)
+	ba := make([]byte, len)
+
+	for i, v := range ca {
+		ba[i] = byte(v)
+		if ba[i] == 0 {
+			len = i
+			break
+		}
+	}
+
+	return string(ba[:len])
+}
+
+// Get ID of device containing path
+func GetPathDeviceId(path string) (deviceId int32, err error) {
+
+	stat := syscall.Stat_t{}
+
+	err = syscall.Stat(path, &stat)
+	if err != nil {
+		return 0, err
+	}
+
+	return stat.Dev, nil
+}
+
+// Executes shell command with timeout and returns stdout
+func CommandWithTimeout(timeoutInSeconds int, name string, arg ...string) (output string, err error) {
+
+	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(timeoutInSeconds)*time.Second)
+	defer cancel()
+
+	cmd := exec.CommandContext(ctx, name, arg...)
+	out, err := cmd.Output()
+
+	if ctx.Err() == context.DeadlineExceeded {
+		err = errors.New("Command '" + name + "' timed out")
+	}
+
+	output = string(out)
+	return output, err
+}
+
+func DeleteShadowCopy() {
+
+	if snapshotPath == "" {
+		return
+	}
+
+	err := exec.Command("/sbin/umount", "-f", snapshotPath).Run()
+	if err != nil {
+		LOG_ERROR("VSS_DELETE", "Error while unmounting snapshot")
+		return
+	}
+
+	err = exec.Command("tmutil", "deletelocalsnapshots", snapshotDate).Run()
+	if err != nil {
+		LOG_ERROR("VSS_DELETE", "Error while deleting local snapshot")
+		return
+	}
+
+	err = os.RemoveAll(snapshotPath)
+	if err != nil {
+		LOG_ERROR("VSS_DELETE", "Error while deleting temporary mount directory")
+		return
+	}
+
+	LOG_INFO("VSS_DELETE", "Shadow copy unmounted and deleted at %s", snapshotPath)
+
+	snapshotPath = ""
+}
+
+func CreateShadowCopy(top string, shadowCopy bool, timeoutInSeconds int) (shadowTop string) {
+
+	if !shadowCopy {
+		return top
+	}
+
+	// Check repository filesystem is APFS
+	stat := syscall.Statfs_t{}
+	err := syscall.Statfs(top, &stat)
+	if err != nil {
+		LOG_ERROR("VSS_INIT", "Unable to determine filesystem of repository path")
+		return top
+	}
+	if CharsToString(stat.Fstypename[:]) != "apfs" {
+		LOG_WARN("VSS_INIT", "VSS requires APFS filesystem")
+		return top
+	}
+
+	// Check path is local as tmutil snapshots will not support APFS formatted external drives
+	deviceIdLocal, err := GetPathDeviceId("/")
+	if err != nil {
+		LOG_ERROR("VSS_INIT", "Unable to get device ID of path: /")
+		return top
+	}
+	deviceIdRepository, err := GetPathDeviceId(top)
+	if err != nil {
+		LOG_ERROR("VSS_INIT", "Unable to get device ID of path: %s", top)
+		return top
+	}
+	if deviceIdLocal != deviceIdRepository {
+		LOG_WARN("VSS_PATH", "VSS not supported for non-local repository path: %s", top)
+		return top
+	}
+
+	if timeoutInSeconds <= 60 {
+		timeoutInSeconds = 60
+	}
+
+	// Create mount point
+	snapshotPath, err = ioutil.TempDir("/tmp/", "snp_")
+	if err != nil {
+		LOG_ERROR("VSS_CREATE", "Failed to create temporary mount directory")
+		return top
+	}
+
+	// Use tmutil to create snapshot
+	tmutilOutput, err := CommandWithTimeout(timeoutInSeconds, "tmutil", "snapshot")
+	if err != nil {
+		LOG_ERROR("VSS_CREATE", "Error while calling tmutil: %v", err)
+		return top
+	}
+
+	colonPos := strings.IndexByte(tmutilOutput, ':')
+	if colonPos < 0 {
+		LOG_ERROR("VSS_CREATE", "Snapshot creation failed: %s", tmutilOutput)
+		return top
+	}
+	snapshotDate = strings.TrimSpace(tmutilOutput[colonPos+1:])
+
+	tmutilOutput, err = CommandWithTimeout(timeoutInSeconds, "tmutil", "listlocalsnapshots", ".")
+	if err != nil {
+		LOG_ERROR("VSS_CREATE", "Error while calling 'tmutil listlocalsnapshots': %v", err)
+		return top
+	}
+	snapshotName := "com.apple.TimeMachine." + snapshotDate
+ 
+	r := regexp.MustCompile(`(?m)^(.+` + snapshotDate + `.*)$`)
+	snapshotNames := r.FindStringSubmatch(tmutilOutput)
+	if len(snapshotNames) > 0 {
+		snapshotName = snapshotNames[0]
+	} else {
+		LOG_WARN("VSS_CREATE", "Error while using 'tmutil listlocalsnapshots' to find snapshot name. Will fallback to 'com.apple.TimeMachine.SNAPSHOT_DATE'")
+	}
+ 
+	// Mount snapshot as readonly and hide from GUI i.e. Finder
+	_, err = CommandWithTimeout(timeoutInSeconds,
+		"/sbin/mount", "-t", "apfs", "-o", "nobrowse,-r,-s="+snapshotName, "/", snapshotPath)
+	if err != nil {
+		LOG_ERROR("VSS_CREATE", "Error while mounting snapshot: %v", err)
+		return top
+	}
+
+	LOG_INFO("VSS_DONE", "Shadow copy created and mounted at %s", snapshotPath)
+
+	return snapshotPath + top
+}

src/duplicacy_snapshot.go

@@ -11,6 +11,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
@@ -57,7 +58,7 @@ func CreateEmptySnapshot(id string) (snapshto *Snapshot) {
 
 // CreateSnapshotFromDirectory creates a snapshot from the local directory 'top'.  Only 'Files'
 // will be constructed, while 'ChunkHashes' and 'ChunkLengths' can only be populated after uploading.
-func CreateSnapshotFromDirectory(id string, top string) (snapshot *Snapshot, skippedDirectories []string,
+func CreateSnapshotFromDirectory(id string, top string, nobackupFile string, filtersFile string) (snapshot *Snapshot, skippedDirectories []string,
 	skippedFiles []string, err error) {
 
 	snapshot = &Snapshot{
@@ -68,47 +69,10 @@ func CreateSnapshotFromDirectory(id string, top string) (snapshot *Snapshot, ski
 
 	var patterns []string
 
-	patternFile, err := ioutil.ReadFile(path.Join(GetDuplicacyPreferencePath(), "filters"))
-	if err == nil {
-		for _, pattern := range strings.Split(string(patternFile), "\n") {
-			pattern = strings.TrimSpace(pattern)
-			if len(pattern) == 0 {
-				continue
-			}
-
-			if pattern[0] == '#' {
-				continue
-			}
-
-			if IsUnspecifiedFilter(pattern) {
-				pattern = "+" + pattern
-			}
-
-			if IsEmptyFilter(pattern) {
-				continue
-			}
-
-			if strings.HasPrefix(pattern, "i:") || strings.HasPrefix(pattern, "e:") {
-				valid, err := IsValidRegex(pattern[2:])
-				if !valid || err != nil {
-					LOG_ERROR("SNAPSHOT_FILTER", "Invalid regular expression encountered for filter: \"%s\", error: %v", pattern, err)
-				}
-			}
-
-			patterns = append(patterns, pattern)
-		}
-
-		LOG_DEBUG("REGEX_DEBUG", "There are %d compiled regular expressions stored", len(RegexMap))
-
-		LOG_INFO("SNAPSHOT_FILTER", "Loaded %d include/exclude pattern(s)", len(patterns))
-
-		if IsTracing() {
-			for _, pattern := range patterns {
-				LOG_TRACE("SNAPSHOT_PATTERN", "Pattern: %s", pattern)
-			}
-		}
-
+	if filtersFile == "" {
+		filtersFile = joinPath(GetDuplicacyPreferencePath(), "filters")
 	}
+	patterns = ProcessFilters(filtersFile)
 
 	directories := make([]*Entry, 0, 256)
 	directories = append(directories, CreateEntry("", 0, 0, 0))
@@ -125,8 +89,12 @@ func CreateSnapshotFromDirectory(id string, top string) (snapshot *Snapshot, ski
 		directory := directories[len(directories)-1]
 		directories = directories[:len(directories)-1]
 		snapshot.Files = append(snapshot.Files, directory)
-		subdirectories, skipped, err := ListEntries(top, directory.Path, &snapshot.Files, patterns, snapshot.discardAttributes)
+		subdirectories, skipped, err := ListEntries(top, directory.Path, &snapshot.Files, patterns, nobackupFile, snapshot.discardAttributes)
 		if err != nil {
+			if directory.Path == "" {
+				LOG_ERROR("LIST_FAILURE", "Failed to list the repository root: %v", err)
+				return nil, nil, nil, err
+			}
 			LOG_WARN("LIST_FAILURE", "Failed to list subdirectory: %v", err)
 			skippedDirectories = append(skippedDirectories, directory.Path)
 			continue
@@ -150,6 +118,103 @@ func CreateSnapshotFromDirectory(id string, top string) (snapshot *Snapshot, ski
 	return snapshot, skippedDirectories, skippedFiles, nil
 }
 
+func AppendPattern(patterns []string, new_pattern string) (new_patterns []string) {
+	for _, pattern := range patterns {
+		if pattern == new_pattern {
+			LOG_INFO("SNAPSHOT_FILTER", "Ignoring duplicate pattern: %s ...", new_pattern)
+			return patterns
+		}
+	}
+	new_patterns = append(patterns, new_pattern)
+	return new_patterns
+}
+func ProcessFilters(filtersFile string) (patterns []string) {
+	patterns = ProcessFilterFile(filtersFile, make([]string, 0))
+
+	LOG_DEBUG("REGEX_DEBUG", "There are %d compiled regular expressions stored", len(RegexMap))
+
+	LOG_INFO("SNAPSHOT_FILTER", "Loaded %d include/exclude pattern(s)", len(patterns))
+
+	if IsTracing() {
+		for _, pattern := range patterns {
+			LOG_TRACE("SNAPSHOT_PATTERN", "Pattern: %s", pattern)
+		}
+
+	}
+
+	return patterns
+}
+
+func ProcessFilterFile(patternFile string, includedFiles []string) (patterns []string) {
+	for _, file := range includedFiles {
+		if file == patternFile {
+			// cycle in include mechanism discovered.
+			LOG_ERROR("SNAPSHOT_FILTER", "The filter file %s has already been included", patternFile)
+			return patterns
+		}
+	}
+	includedFiles = append(includedFiles, patternFile)
+	LOG_INFO("SNAPSHOT_FILTER", "Parsing filter file %s", patternFile)
+	patternFileContent, err := ioutil.ReadFile(patternFile)
+	if err == nil {
+		patternFileLines := strings.Split(string(patternFileContent), "\n")
+		patterns = ProcessFilterLines(patternFileLines, includedFiles)
+	}
+	return patterns
+}
+
+func ProcessFilterLines(patternFileLines []string, includedFiles []string) (patterns []string) {
+	for _, pattern := range patternFileLines {
+		pattern = strings.TrimSpace(pattern)
+		if len(pattern) == 0 {
+			continue
+		}
+
+		if strings.HasPrefix(pattern, "@") {
+			patternIncludeFile := strings.TrimSpace(pattern[1:])
+			if patternIncludeFile == "" {
+				continue
+			}
+			if ! filepath.IsAbs(patternIncludeFile) {
+				basePath := ""
+				if len(includedFiles) == 0 {
+					basePath, _ = os.Getwd()
+				} else {
+					basePath = filepath.Dir(includedFiles[len(includedFiles)-1])
+				}
+				patternIncludeFile = joinPath(basePath, patternIncludeFile)
+			}
+			for _, pattern := range ProcessFilterFile(patternIncludeFile, includedFiles) {
+				patterns = AppendPattern(patterns, pattern)
+			}
+			continue
+		}
+
+		if pattern[0] == '#' {
+			continue
+		}
+
+		if IsUnspecifiedFilter(pattern) {
+			pattern = "+" + pattern
+		}
+
+		if IsEmptyFilter(pattern) {
+			continue
+		}
+
+		if strings.HasPrefix(pattern, "i:") || strings.HasPrefix(pattern, "e:") {
+			valid, err := IsValidRegex(pattern[2:])
+			if !valid || err != nil {
+				LOG_ERROR("SNAPSHOT_FILTER", "Invalid regular expression encountered for filter: \"%s\", error: %v", pattern, err)
+			}
+		}
+
+		patterns = AppendPattern(patterns, pattern)
+	}
+
+	return patterns
+}
+
 // This is the struct used to save/load incomplete snapshots
 type IncompleteSnapshot struct {
 	Files        []*Entry

src/duplicacy_snapshotmanager.go

@@ -38,6 +38,9 @@ type FossilCollection struct {
 	// The lastest revision for each snapshot id when the fossil collection was created.
 	LastRevisions map[string]int `json:"last_revisions"`
 
+	// Record the set of snapshots that have been removed by the prune command that created this fossil collection
+	DeletedRevisions map[string][]int `json:"deleted_revisions"`
+
 	// Fossils (i.e., chunks not referenced by any snapshots)
 	Fossils []string `json:"fossils"`
 
@@ -54,7 +57,8 @@ func CreateFossilCollection(allSnapshots map[string][]*Snapshot) *FossilCollecti
 	}
 
 	return &FossilCollection{
-		LastRevisions: lastRevisions,
+		LastRevisions:    lastRevisions,
+		DeletedRevisions: make(map[string][]int),
 	}
 }
 
@@ -105,6 +109,8 @@ func (collection *FossilCollection) IsDeletable(isStrongConsistent bool, ignored
 				continue
 			}
 
+			newSnapshots = append(newSnapshots, snapshot)
+
 			extraTime := 0
 			if !isStrongConsistent {
 				extraTime = secondsInDay / 2
@@ -114,7 +120,6 @@ func (collection *FossilCollection) IsDeletable(isStrongConsistent bool, ignored
 			// might be in progress (although very unlikely).  So we only deem it deletable if that is not the case.
 			if snapshot.EndTime > collection.EndTime+int64(extraTime) {
 				hasNewSnapshot[hostID] = true
-				newSnapshots = append(newSnapshots, snapshot)
 				break
 			} else {
 				LOG_TRACE("SNAPSHOT_UNDELETABLE",
@@ -165,6 +170,16 @@ func (collection *FossilCollection) IsEmpty() bool {
 	return len(collection.Fossils) == 0 && len(collection.Temporaries) == 0
 }
 
+// Calculates the number of days between two times ignoring the hours, minutes and seconds.
+func getDaysBetween(start int64, end int64) int {
+	startTime := time.Unix(start, 0).In(time.Now().Location())
+	endTime := time.Unix(end, 0).In(time.Now().Location())
+	startDate := time.Date(startTime.Year(), startTime.Month(), startTime.Day(), 0, 0, 0, 0, startTime.Location())
+	endDate := time.Date(endTime.Year(), endTime.Month(), endTime.Day(), 0, 0, 0, 0, endTime.Location())
+	hours := int(endDate.Sub(startDate).Hours())
+	return (hours + 1) / 24
+}
+
 // SnapshotManager is mainly responsible for downloading, and deleting snapshots.
 type SnapshotManager struct {
 
@@ -175,6 +190,7 @@ type SnapshotManager struct {
 	snapshotCache *FileStorage
 
 	chunkDownloader *ChunkDownloader
+	chunkOperator   *ChunkOperator
 }
 
 // CreateSnapshotManager creates a snapshot manager
@@ -365,12 +381,19 @@ func (manager *SnapshotManager) DownloadSnapshotContents(snapshot *Snapshot, pat
 	return true
 }
 
+// ClearSnapshotContents removes contents loaded by DownloadSnapshotContents
+func (manager *SnapshotManager) ClearSnapshotContents(snapshot *Snapshot) {
+	snapshot.ChunkHashes = nil
+	snapshot.ChunkLengths = nil
+	snapshot.Files = nil
+}
+
 // CleanSnapshotCache removes all files not referenced by the specified 'snapshot' in the snapshot cache.
 func (manager *SnapshotManager) CleanSnapshotCache(latestSnapshot *Snapshot, allSnapshots map[string][]*Snapshot) bool {
 
 	if allSnapshots == nil {
 		// If the 'fossils' directory exists then don't clean the cache as all snapshots will be needed later
-		// during the fossil collection phase.  The deletion procedure creates this direcotry.
+		// during the fossil collection phase.  The deletion procedure creates this directory.
 		// We only check this condition when allSnapshots is nil because
 		// in thise case it is the deletion procedure that is trying to clean the snapshot cache.
 		exist, _, _, err := manager.snapshotCache.GetFileInfo(0, "fossils")
@@ -637,6 +660,51 @@ func (manager *SnapshotManager) GetSnapshotChunks(snapshot *Snapshot, keepChunkH
 	return chunks
 }
 
+// GetSnapshotChunkHashes has an option to retrieve chunk hashes in addition to chunk ids.
+func (manager *SnapshotManager) GetSnapshotChunkHashes(snapshot *Snapshot, chunkHashes *map[string]bool, chunkIDs map[string]bool) {
+
+	for _, chunkHash := range snapshot.FileSequence {
+		if chunkHashes != nil {
+			(*chunkHashes)[chunkHash] = true
+		}
+		chunkIDs[manager.config.GetChunkIDFromHash(chunkHash)] = true
+	}
+
+	for _, chunkHash := range snapshot.ChunkSequence {
+		if chunkHashes != nil {
+			(*chunkHashes)[chunkHash] = true
+		}
+		chunkIDs[manager.config.GetChunkIDFromHash(chunkHash)] = true
+	}
+
+	for _, chunkHash := range snapshot.LengthSequence {
+		if chunkHashes != nil {
+			(*chunkHashes)[chunkHash] = true
+		}
+		chunkIDs[manager.config.GetChunkIDFromHash(chunkHash)] = true
+	}
+
+	if len(snapshot.ChunkHashes) == 0 {
+
+		description := manager.DownloadSequence(snapshot.ChunkSequence)
+		err := snapshot.LoadChunks(description)
+		if err != nil {
+			LOG_ERROR("SNAPSHOT_CHUNK", "Failed to load chunks for snapshot %s at revision %d: %v",
+				snapshot.ID, snapshot.Revision, err)
+			return
+		}
+	}
+
+	for _, chunkHash := range snapshot.ChunkHashes {
+		if chunkHashes != nil {
+			(*chunkHashes)[chunkHash] = true
+		}
+		chunkIDs[manager.config.GetChunkIDFromHash(chunkHash)] = true
+	}
+
+	snapshot.ClearChunks()
+}
+
 // ListSnapshots shows the information about a snapshot.
 func (manager *SnapshotManager) ListSnapshots(snapshotID string, revisionsToList []int, tag string,
 	showFiles bool, showChunks bool) int {
@@ -673,6 +741,9 @@ func (manager *SnapshotManager) ListSnapshots(snapshotID string, revisionsToList
 		for _, revision := range revisions {
 
 			snapshot := manager.DownloadSnapshot(snapshotID, revision)
+			if tag != "" && snapshot.Tag != tag {
+				continue
+			}
 			creationTime := time.Unix(snapshot.StartTime, 0).Format("2006-01-02 15:04")
 			tagWithSpace := ""
 			if len(snapshot.Tag) > 0 {
@@ -681,15 +752,16 @@ func (manager *SnapshotManager) ListSnapshots(snapshotID string, revisionsToList
 			LOG_INFO("SNAPSHOT_INFO", "Snapshot %s revision %d created at %s %s%s",
 				snapshotID, revision, creationTime, tagWithSpace, snapshot.Options)
 
-			if tag != "" && snapshot.Tag != tag {
-				continue
-			}
-
 			if showFiles {
 				manager.DownloadSnapshotFileSequence(snapshot, nil, false)
 			}
 
 			if showFiles {
+
+				if snapshot.NumberOfFiles > 0 {
+					LOG_INFO("SNAPSHOT_STATS", "Files: %d", snapshot.NumberOfFiles)
+				}
+
 				maxSize := int64(9)
 				maxSizeDigits := 1
 				totalFiles := 0
@@ -737,10 +809,12 @@ func (manager *SnapshotManager) ListSnapshots(snapshotID string, revisionsToList
 
 // ListSnapshots shows the information about a snapshot.
 func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToCheck []int, tag string, showStatistics bool, showTabular bool,
-	checkFiles bool, searchFossils bool, resurrect bool) bool {
+	checkFiles bool, checkChunks, searchFossils bool, resurrect bool, threads int) bool {
 
-	LOG_DEBUG("LIST_PARAMETERS", "id: %s, revisions: %v, tag: %s, showStatistics: %t, checkFiles: %t, searchFossils: %t, resurrect: %t",
-		snapshotID, revisionsToCheck, tag, showStatistics, checkFiles, searchFossils, resurrect)
+	manager.chunkDownloader = CreateChunkDownloader(manager.config, manager.storage, manager.snapshotCache, false, threads)
+
+	LOG_DEBUG("LIST_PARAMETERS", "id: %s, revisions: %v, tag: %s, showStatistics: %t, showTabular: %t, checkFiles: %t, searchFossils: %t, resurrect: %t",
+		snapshotID, revisionsToCheck, tag, showStatistics, showTabular, checkFiles, searchFossils, resurrect)
 
 	snapshotMap := make(map[string][]*Snapshot)
 	var err error
@@ -754,6 +828,8 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 	// Store the index of the snapshot that references each chunk; if the chunk is shared by multiple chunks, the index is -1
 	chunkSnapshotMap := make(map[string]int)
 
+	emptyChunks := 0
+
 	LOG_INFO("SNAPSHOT_CHECK", "Listing all chunks")
 	allChunks, allSizes := manager.ListAllFiles(manager.storage, chunkDir)
 
@@ -768,9 +844,14 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 
 		chunk = strings.Replace(chunk, "/", "", -1)
 		chunkSizeMap[chunk] = allSizes[i]
+
+		if allSizes[i] == 0 && !strings.HasSuffix(chunk, ".tmp") {
+			LOG_WARN("SNAPSHOT_CHECK", "Chunk %s has a size of 0", chunk)
+			emptyChunks++
+		}
 	}
 
-	if snapshotID == "" || showStatistics {
+	if snapshotID == "" || showStatistics || showTabular {
 		snapshotIDs, err := manager.ListSnapshotIDs()
 		if err != nil {
 			LOG_ERROR("SNAPSHOT_LIST", "Failed to list all snapshots: %v", err)
@@ -786,10 +867,11 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 	}
 
 	snapshotIDIndex := 0
-	for snapshotID, _ = range snapshotMap {
+	totalMissingChunks := 0
+	for snapshotID = range snapshotMap {
 
 		revisions := revisionsToCheck
-		if len(revisions) == 0 || showStatistics {
+		if len(revisions) == 0 || showStatistics || showTabular {
 			revisions, err = manager.ListSnapshotRevisions(snapshotID)
 			if err != nil {
 				LOG_ERROR("SNAPSHOT_LIST", "Failed to list all revisions for snapshot %s: %v", snapshotID, err)
@@ -799,40 +881,76 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 
 		for _, revision := range revisions {
 			snapshot := manager.DownloadSnapshot(snapshotID, revision)
-			snapshotMap[snapshotID] = append(snapshotMap[snapshotID], snapshot)
-
 			if tag != "" && snapshot.Tag != tag {
 				continue
 			}
+			snapshotMap[snapshotID] = append(snapshotMap[snapshotID], snapshot)
+		}
+	}
+
+	totalRevisions := 0
+	for _, snapshotList := range snapshotMap {
+		totalRevisions += len(snapshotList)
+	}
+	LOG_INFO("SNAPSHOT_CHECK", "%d snapshots and %d revisions", len(snapshotMap), totalRevisions)
+
+	var totalChunkSize int64
+	for _, size := range chunkSizeMap {
+		totalChunkSize += size
+	}
+	LOG_INFO("SNAPSHOT_CHECK", "Total chunk size is %s in %d chunks", PrettyNumber(totalChunkSize), len(chunkSizeMap))
+
+	var allChunkHashes *map[string]bool
+	if checkChunks && !checkFiles {
+		m := make(map[string]bool)
+		allChunkHashes = &m
+	}
+
+	for snapshotID = range snapshotMap {
+
+		for _, snapshot := range snapshotMap[snapshotID] {
 
 			if checkFiles {
 				manager.DownloadSnapshotContents(snapshot, nil, false)
 				manager.VerifySnapshot(snapshot)
+				manager.ClearSnapshotContents(snapshot)
 				continue
 			}
 
 			chunks := make(map[string]bool)
-			for _, chunkID := range manager.GetSnapshotChunks(snapshot, false) {
-				chunks[chunkID] = true
-			}
+			manager.GetSnapshotChunkHashes(snapshot, allChunkHashes, chunks)
 
 			missingChunks := 0
-			for chunkID, _ := range chunks {
+			for chunkID := range chunks {
 
 				_, found := chunkSizeMap[chunkID]
 
 				if !found {
+
+					// Look up the chunk again in case it actually exists, but only if there aren't
+					// too many missing chunks.
+					if missingChunks < 100 {
+						_, exist, _, err := manager.storage.FindChunk(0, chunkID, false)
+						if err != nil {
+							LOG_WARN("SNAPSHOT_VALIDATE", "Failed to check the existence of chunk %s: %v",
+							         chunkID, err)
+						} else if exist {
+							LOG_INFO("SNAPSHOT_VALIDATE", "Chunk %s is confirmed to exist", chunkID)
+							continue
+						}
+					}
+
 					if !searchFossils {
 						missingChunks += 1
 						LOG_WARN("SNAPSHOT_VALIDATE",
 							"Chunk %s referenced by snapshot %s at revision %d does not exist",
-							chunkID, snapshotID, revision)
+							chunkID, snapshotID, snapshot.Revision)
 						continue
 					}
 
 					chunkPath, exist, size, err := manager.storage.FindChunk(0, chunkID, true)
 					if err != nil {
-						LOG_ERROR("SNAPSHOT_VALIDATE", "Failed to check the existence of chunk %s: %v",
+						LOG_ERROR("SNAPSHOT_VALIDATE", "Failed to check the existence of fossil %s: %v",
 							chunkID, err)
 						return false
 					}
@@ -841,7 +959,7 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 						missingChunks += 1
 						LOG_WARN("SNAPSHOT_VALIDATE",
 							"Chunk %s referenced by snapshot %s at revision %d does not exist",
-							chunkID, snapshotID, revision)
+							chunkID, snapshotID, snapshot.Revision)
 						continue
 					}
 
@@ -849,7 +967,7 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 						manager.resurrectChunk(chunkPath, chunkID)
 					} else {
 						LOG_WARN("SNAPSHOT_FOSSIL", "Chunk %s referenced by snapshot %s at revision %d "+
-							"has been marked as a fossil", chunkID, snapshotID, revision)
+							"has been marked as a fossil", chunkID, snapshotID, snapshot.Revision)
 					}
 
 					chunkSizeMap[chunkID] = size
@@ -871,24 +989,43 @@ func (manager *SnapshotManager) CheckSnapshots(snapshotID string, revisionsToChe
 			}
 
 			if missingChunks > 0 {
-				LOG_ERROR("SNAPSHOT_CHECK", "Some chunks referenced by snapshot %s at revision %d are missing",
-					snapshotID, revision)
-				return false
+				LOG_WARN("SNAPSHOT_CHECK", "Some chunks referenced by snapshot %s at revision %d are missing",
+					snapshotID, snapshot.Revision)
+				totalMissingChunks += missingChunks
+			} else {
+				LOG_INFO("SNAPSHOT_CHECK", "All chunks referenced by snapshot %s at revision %d exist",
+					snapshotID, snapshot.Revision)
 			}
-
-			LOG_INFO("SNAPSHOT_CHECK", "All chunks referenced by snapshot %s at revision %d exist",
-				snapshotID, revision)
 		}
 
 		snapshotIDIndex += 1
 	}
 
+	if totalMissingChunks > 0 {
+		LOG_ERROR("SNAPSHOT_CHECK", "Some chunks referenced by some snapshots do not exist in the storage")
+		return false
+	}
+
+	if emptyChunks > 0 {
+		LOG_ERROR("SNAPSHOT_CHECK", "%d chunks have a size of 0", emptyChunks)
+		return false
+	}
+
 	if showTabular {
 		manager.ShowStatisticsTabular(snapshotMap, chunkSizeMap, chunkUniqueMap, chunkSnapshotMap)
 	} else if showStatistics {
 		manager.ShowStatistics(snapshotMap, chunkSizeMap, chunkUniqueMap, chunkSnapshotMap)
 	}
 
+	if checkChunks && !checkFiles {
+		manager.chunkDownloader.snapshotCache = nil
+		LOG_INFO("SNAPSHOT_VERIFY", "Verifying %d chunks", len(*allChunkHashes))
+		for chunkHash := range *allChunkHashes {
+			manager.chunkDownloader.AddChunk(chunkHash)
+		}
+		manager.chunkDownloader.WaitForCompletion()
+		LOG_INFO("SNAPSHOT_VERIFY", "All %d chunks have been successfully verified", len(*allChunkHashes))
+	}
 	return true
 }
 
@@ -910,7 +1047,7 @@ func (manager *SnapshotManager) ShowStatistics(snapshotMap map[string][]*Snapsho
 			var totalChunkSize int64
 			var uniqueChunkSize int64
 
-			for chunkID, _ := range chunks {
+			for chunkID := range chunks {
 				chunkSize := chunkSizeMap[chunkID]
 				totalChunkSize += chunkSize
 				if chunkUniqueMap[chunkID] {
@@ -928,7 +1065,7 @@ func (manager *SnapshotManager) ShowStatistics(snapshotMap map[string][]*Snapsho
 
 		var totalChunkSize int64
 		var uniqueChunkSize int64
-		for chunkID, _ := range snapshotChunks {
+		for chunkID := range snapshotChunks {
 			chunkSize := chunkSizeMap[chunkID]
 			totalChunkSize += chunkSize
 
@@ -955,18 +1092,20 @@ func (manager *SnapshotManager) ShowStatisticsTabular(snapshotMap map[string][]*
 		earliestSeenChunks := make(map[string]int)
 
 		for _, snapshot := range snapshotList {
-			for _, chunkID := range manager.GetSnapshotChunks(snapshot, true) {
+			for _, chunkID := range manager.GetSnapshotChunks(snapshot, false) {
 				if earliestSeenChunks[chunkID] == 0 {
 					earliestSeenChunks[chunkID] = math.MaxInt32
 				}
-				earliestSeenChunks[chunkID] = MinInt(earliestSeenChunks[chunkID], snapshot.Revision)
+				if earliestSeenChunks[chunkID] > snapshot.Revision {
+					earliestSeenChunks[chunkID] = snapshot.Revision
+				}
 			}
 		}
 
 		for _, snapshot := range snapshotList {
 
 			chunks := make(map[string]bool)
-			for _, chunkID := range manager.GetSnapshotChunks(snapshot, true) {
+			for _, chunkID := range manager.GetSnapshotChunks(snapshot, false) {
 				chunks[chunkID] = true
 				snapshotChunks[chunkID] = true
 			}
@@ -978,7 +1117,7 @@ func (manager *SnapshotManager) ShowStatisticsTabular(snapshotMap map[string][]*
 			var newChunkCount int64
 			var newChunkSize int64
 
-			for chunkID, _ := range chunks {
+			for chunkID := range chunks {
 				chunkSize := chunkSizeMap[chunkID]
 				totalChunkSize += chunkSize
 				totalChunkCount += 1
@@ -1006,7 +1145,7 @@ func (manager *SnapshotManager) ShowStatisticsTabular(snapshotMap map[string][]*
 		var uniqueChunkSize int64
 		var totalChunkCount int64
 		var uniqueChunkCount int64
-		for chunkID, _ := range snapshotChunks {
+		for chunkID := range snapshotChunks {
 			chunkSize := chunkSizeMap[chunkID]
 			totalChunkSize += chunkSize
 			totalChunkCount += 1
@@ -1111,7 +1250,7 @@ func (manager *SnapshotManager) VerifySnapshot(snapshot *Snapshot) bool {
 	}
 }
 
-// RetrieveFile retrieve the file in the specifed snapshot.
+// RetrieveFile retrieves the file in the specified snapshot.
 func (manager *SnapshotManager) RetrieveFile(snapshot *Snapshot, file *Entry, output func([]byte)) bool {
 
 	if file.Size == 0 {
@@ -1135,7 +1274,6 @@ func (manager *SnapshotManager) RetrieveFile(snapshot *Snapshot, file *Entry, ou
 	}
 
 	var chunk *Chunk
-	currentHash := ""
 
 	for i := file.StartChunk; i <= file.EndChunk; i++ {
 		start := 0
@@ -1148,10 +1286,12 @@ func (manager *SnapshotManager) RetrieveFile(snapshot *Snapshot, file *Entry, ou
 		}
 
 		hash := snapshot.ChunkHashes[i]
-		if currentHash != hash {
+		lastChunk, lastChunkHash := manager.chunkDownloader.GetLastDownloadedChunk()
+		if lastChunkHash != hash {
 			i := manager.chunkDownloader.AddChunk(hash)
 			chunk = manager.chunkDownloader.WaitForChunk(i)
-			currentHash = hash
+		} else {
+			chunk = lastChunk
 		}
 
 		output(chunk.GetBytes()[start:end])
@@ -1226,21 +1366,20 @@ func (manager *SnapshotManager) PrintFile(snapshotID string, revision int, path
 	}
 
 	file := manager.FindFile(snapshot, path, false)
-	var content []byte
-	if !manager.RetrieveFile(snapshot, file, func(chunk []byte) { content = append(content, chunk...) }) {
+	if !manager.RetrieveFile(snapshot, file, func(chunk []byte) {
+			fmt.Printf("%s", chunk)
+		}) {
 		LOG_ERROR("SNAPSHOT_RETRIEVE", "File %s is corrupted in snapshot %s at revision %d",
 			path, snapshot.ID, snapshot.Revision)
 		return false
 	}
 
-	fmt.Printf("%s", string(content))
-
 	return true
 }
 
 // Diff compares two snapshots, or two revision of a file if the file argument is given.
 func (manager *SnapshotManager) Diff(top string, snapshotID string, revisions []int,
-	filePath string, compareByHash bool) bool {
+	filePath string, compareByHash bool, nobackupFile string, filtersFile string) bool {
 
 	LOG_DEBUG("DIFF_PARAMETERS", "top: %s, id: %s, revision: %v, path: %s, compareByHash: %t",
 		top, snapshotID, revisions, filePath, compareByHash)
@@ -1253,7 +1392,7 @@ func (manager *SnapshotManager) Diff(top string, snapshotID string, revisions []
 	if len(revisions) <= 1 {
 		// Only scan the repository if filePath is not provided
 		if len(filePath) == 0 {
-			rightSnapshot, _, _, err = CreateSnapshotFromDirectory(snapshotID, top)
+			rightSnapshot, _, _, err = CreateSnapshotFromDirectory(snapshotID, top, nobackupFile, filtersFile)
 			if err != nil {
 				LOG_ERROR("SNAPSHOT_LIST", "Failed to list the directory %s: %v", top, err)
 				return false
@@ -1424,7 +1563,11 @@ func (manager *SnapshotManager) Diff(top string, snapshotID string, revisions []
 						same = right.IsSameAs(left)
 					}
 				} else {
-					same = left.Hash == right.Hash
+					if left.Size == 0 && right.Size == 0 {
+						same = true
+					} else {
+						same = left.Hash == right.Hash
+					}
 				}
 
 				if !same {
@@ -1490,7 +1633,7 @@ func (manager *SnapshotManager) ShowHistory(top string, snapshotID string, revis
 		}
 		if showLocalHash {
 			localFile.Hash = manager.config.ComputeFileHash(joinPath(top, filePath), make([]byte, 32*1024))
-			if lastVersion.Hash != localFile.Hash {
+			if lastVersion == nil || lastVersion.Hash != localFile.Hash {
 				modifiedFlag = "*"
 			}
 		}
@@ -1503,36 +1646,11 @@ func (manager *SnapshotManager) ShowHistory(top string, snapshotID string, revis
 }
 
 // fossilizeChunk turns the chunk into a fossil.
-func (manager *SnapshotManager) fossilizeChunk(chunkID string, filePath string,
-	exclusive bool, collection *FossilCollection) bool {
+func (manager *SnapshotManager) fossilizeChunk(chunkID string, filePath string, exclusive bool) bool {
 	if exclusive {
-		err := manager.storage.DeleteFile(0, filePath)
-		if err != nil {
-			LOG_ERROR("CHUNK_DELETE", "Failed to remove the chunk %s: %v", chunkID, err)
-			return false
-		} else {
-			LOG_TRACE("CHUNK_DELETE", "Deleted chunk file %s", chunkID)
-		}
-
+		manager.chunkOperator.Delete(chunkID, filePath)
 	} else {
-		fossilPath := filePath + ".fsl"
-
-		err := manager.storage.MoveFile(0, filePath, fossilPath)
-		if err != nil {
-			if _, exist, _, _ := manager.storage.FindChunk(0, chunkID, true); exist {
-				err := manager.storage.DeleteFile(0, filePath)
-				if err == nil {
-					LOG_TRACE("CHUNK_DELETE", "Deleted chunk file %s as the fossil already exists", chunkID)
-				}
-			} else {
-				LOG_ERROR("CHUNK_DELETE", "Failed to fossilize the chunk %s: %v", chunkID, err)
-				return false
-			}
-		} else {
-			LOG_TRACE("CHUNK_FOSSILIZE", "Fossilized chunk %s", chunkID)
-		}
-
-		collection.AddFossil(fossilPath)
+		manager.chunkOperator.Fossilize(chunkID, filePath)
 	}
 
 	return true
@@ -1581,7 +1699,7 @@ func (manager *SnapshotManager) resurrectChunk(fossilPath string, chunkID string
 func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string, revisionsToBeDeleted []int,
 	tags []string, retentions []string,
 	exhaustive bool, exclusive bool, ignoredIDs []string,
-	dryRun bool, deleteOnly bool, collectOnly bool) bool {
+	dryRun bool, deleteOnly bool, collectOnly bool, threads int) bool {
 
 	LOG_DEBUG("DELETE_PARAMETERS",
 		"id: %s, revisions: %v, tags: %v, retentions: %v, exhaustive: %t, exclusive: %t, "+
@@ -1593,6 +1711,9 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 		LOG_WARN("DELETE_OPTIONS", "Tags or retention policy will be ignored if at least one revision is specified")
 	}
 
+	manager.chunkOperator = CreateChunkOperator(manager.storage, threads)
+	defer manager.chunkOperator.Stop()
+
 	prefPath := GetDuplicacyPreferencePath()
 	logDir := path.Join(prefPath, "logs")
 	err := os.MkdirAll(logDir, 0700)
@@ -1762,6 +1883,29 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 			return false
 		}
 
+		// Determine if any deleted revisions exist
+		exist := false
+		for snapshotID, revisionList := range collection.DeletedRevisions {
+			for _, revision := range revisionList {
+				for _, snapshot := range allSnapshots[snapshotID] {
+					if revision == snapshot.Revision {
+						LOG_INFO("FOSSIL_GHOSTSNAPSHOT", "Snapshot %s revision %d should have been deleted already", snapshotID, revision)
+						exist = true
+					}
+				}
+			}
+		}
+
+		if exist {
+			err = manager.snapshotCache.DeleteFile(0, collectionFile)
+			if err != nil {
+				LOG_WARN("FOSSIL_FILE", "Failed to remove the fossil collection file %s: %v", collectionFile, err)
+			} else {
+				LOG_INFO("FOSSIL_IGNORE", "The fossil collection file %s has been ignored due to ghost snapshots", collectionFile)
+			}
+			continue
+		}
+
 		for _, fossil := range collection.Fossils {
 			referencedFossils[fossil] = true
 		}
@@ -1778,6 +1922,8 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 			newChunks := make(map[string]bool)
 
 			for _, newSnapshot := range newSnapshots {
+				fmt.Fprintf(logFile, "Snapshot %s revision %d was created after collection %s\n", newSnapshot.ID, newSnapshot.Revision, collectionName)
+				LOG_INFO("PRUNE_NEWSNAPSHOT", "Snapshot %s revision %d was created after collection %s", newSnapshot.ID, newSnapshot.Revision, collectionName)
 				for _, chunk := range manager.GetSnapshotChunks(newSnapshot, false) {
 					newChunks[chunk] = true
 				}
@@ -1792,24 +1938,19 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 				if _, found := newChunks[chunk]; found {
 					// The fossil is referenced so it can't be deleted.
 					if dryRun {
-						LOG_INFO("FOSSIL_RESURRECT", "Fossil %s would be resurrected: %v", chunk)
+						LOG_INFO("FOSSIL_RESURRECT", "Fossil %s would be resurrected", chunk)
 						continue
 					}
 
-					manager.resurrectChunk(fossil, chunk)
+					manager.chunkOperator.Resurrect(chunk, fossil)
 					fmt.Fprintf(logFile, "Resurrected fossil %s (collection %s)\n", chunk, collectionName)
 
 				} else {
 					if dryRun {
 						LOG_INFO("FOSSIL_DELETE", "The chunk %s would be permanently removed", chunk)
 					} else {
-						err = manager.storage.DeleteFile(0, fossil)
-						if err != nil {
-							LOG_WARN("FOSSIL_DELETE", "The chunk %s could not be removed: %v", chunk, err)
-						} else {
-							LOG_INFO("FOSSIL_DELETE", "The chunk %s has been permanently removed", chunk)
-							fmt.Fprintf(logFile, "Deleted fossil %s (collection %s)\n", chunk, collectionName)
-						}
+						manager.chunkOperator.Delete(chunk, fossil)
+						fmt.Fprintf(logFile, "Deleted fossil %s (collection %s)\n", chunk, collectionName)
 					}
 				}
 			}
@@ -1820,8 +1961,7 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 					LOG_INFO("TEMPORARY_DELETE", "The temporary file %s would be deleted", temporary)
 				} else {
 					// Fail silently, since temporary files are supposed to be renamed or deleted after upload is done
-					_ = manager.storage.DeleteFile(0, temporary)
-					LOG_INFO("TEMPORARY_DELETE", "The temporary file %s has been deleted", temporary)
+					manager.chunkOperator.Delete("", temporary)
 					fmt.Fprintf(logFile, "Deleted temporary %s (collection %s)\n", temporary, collectionName)
 				}
 			}
@@ -1898,7 +2038,7 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 
 				// Find out which retent policy applies based on the age.
 				for i < len(retentionPolicies) &&
-					int(now-snapshot.StartTime) < retentionPolicies[i].Age*secondsInDay {
+					getDaysBetween(snapshot.StartTime, now) < retentionPolicies[i].Age {
 					i++
 					lastSnapshotTime = 0
 				}
@@ -1911,9 +2051,8 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 						snapshot.Flag = true
 						toBeDeleted++
 					} else if lastSnapshotTime != 0 &&
-						int(snapshot.StartTime-lastSnapshotTime) < retentionPolicies[i].Interval*secondsInDay-600 {
-						// Delete the snapshot if it is too close to the last kept one.  Note that a tolerance of 10
-						// minutes was subtracted from the interval.
+						getDaysBetween(lastSnapshotTime, snapshot.StartTime) < retentionPolicies[i].Interval {
+						// Delete the snapshot if it is too close to the last kept one.
 						LOG_DEBUG("SNAPSHOT_DELETE", "Snapshot %s at revision %d to be deleted - older than %d days, less than %d days from previous",
 							snapshot.ID, snapshot.Revision, retentionPolicies[i].Age, retentionPolicies[i].Interval)
 						snapshot.Flag = true
@@ -1949,14 +2088,28 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 	if exhaustive {
 		success = manager.pruneSnapshotsExhaustive(referencedFossils, allSnapshots, collection, logFile, dryRun, exclusive)
 	} else {
-		success = manager.pruneSnapshots(allSnapshots, collection, logFile, dryRun, exclusive)
+		success = manager.pruneSnapshotsNonExhaustive(allSnapshots, collection, logFile, dryRun, exclusive)
 	}
 	if !success {
 		return false
 	}
 
+	manager.chunkOperator.Stop()
+	for _, fossil := range manager.chunkOperator.fossils {
+		collection.AddFossil(fossil)
+	}
+
+	// Save the deleted revision in the fossil collection
+	for _, snapshots := range allSnapshots {
+		for _, snapshot := range snapshots {
+			if snapshot.Flag {
+				collection.DeletedRevisions[snapshot.ID] = append(collection.DeletedRevisions[snapshot.ID], snapshot.Revision)
+			}
+		}
+	}
+
 	// Save the fossil collection if it is not empty.
-	if !collection.IsEmpty() && !dryRun {
+	if !collection.IsEmpty() && !dryRun && !exclusive {
 		collection.EndTime = time.Now().Unix()
 
 		collectionNumber := maxCollectionNumber + 1
@@ -2028,7 +2181,7 @@ func (manager *SnapshotManager) PruneSnapshots(selfID string, snapshotID string,
 
 // pruneSnapshots in non-exhaustive mode, only chunks that exist in the
 // snapshots to be deleted but not other are identified as unreferenced chunks.
-func (manager *SnapshotManager) pruneSnapshots(allSnapshots map[string][]*Snapshot, collection *FossilCollection, logFile io.Writer, dryRun, exclusive bool) bool {
+func (manager *SnapshotManager) pruneSnapshotsNonExhaustive(allSnapshots map[string][]*Snapshot, collection *FossilCollection, logFile io.Writer, dryRun, exclusive bool) bool {
 	targetChunks := make(map[string]bool)
 
 	// Now build all chunks referened by snapshot not deleted
@@ -2085,18 +2238,7 @@ func (manager *SnapshotManager) pruneSnapshots(allSnapshots map[string][]*Snapsh
 			continue
 		}
 
-		chunkPath, exist, _, err := manager.storage.FindChunk(0, chunk, false)
-		if err != nil {
-			LOG_ERROR("CHUNK_FIND", "Failed to locate the path for the chunk %s: %v", chunk, err)
-			return false
-		}
-
-		if !exist {
-			LOG_WARN("CHUNK_MISSING", "The chunk %s does not exist", chunk)
-			continue
-		}
-
-		manager.fossilizeChunk(chunk, chunkPath, exclusive, collection)
+		manager.fossilizeChunk(chunk, "", exclusive)
 		if exclusive {
 			fmt.Fprintf(logFile, "Deleted chunk %s (exclusive mode)\n", chunk)
 		} else {
@@ -2158,12 +2300,7 @@ func (manager *SnapshotManager) pruneSnapshotsExhaustive(referencedFossils map[s
 
 			if exclusive {
 				// In exclusive mode, we assume no other restore operation is running concurrently.
-				err := manager.storage.DeleteFile(0, chunkDir+file)
-				if err != nil {
-					LOG_ERROR("CHUNK_TEMPORARY", "Failed to remove the temporary file %s: %v", file, err)
-					return false
-				}
-				LOG_DEBUG("CHUNK_TEMPORARY", "Deleted temporary file %s", file)
+				manager.chunkOperator.Delete("", chunkDir+file)
 				fmt.Fprintf(logFile, "Deleted temporary %s\n", file)
 			} else {
 				collection.AddTemporary(file)
@@ -2173,24 +2310,34 @@ func (manager *SnapshotManager) pruneSnapshotsExhaustive(referencedFossils map[s
 			// This is a fossil.  If it is unreferenced, it can be a result of failing to save the fossil
 			// collection file after making it a fossil.
 			if _, found := referencedFossils[file]; !found {
-				if dryRun {
-					LOG_INFO("FOSSIL_UNREFERENCED", "Found unreferenced fossil %s", file)
-					continue
-				}
 
 				chunk := strings.Replace(file, "/", "", -1)
 				chunk = strings.Replace(chunk, ".fsl", "", -1)
 
 				if _, found := referencedChunks[chunk]; found {
-					manager.resurrectChunk(chunkDir+file, chunk)
-				} else {
-					err := manager.storage.DeleteFile(0, chunkDir+file)
-					if err != nil {
-						LOG_WARN("FOSSIL_DELETE", "Failed to remove the unreferenced fossil %s: %v", file, err)
-					} else {
-						LOG_DEBUG("FOSSIL_DELETE", "Deleted unreferenced fossil %s", file)
-						fmt.Fprintf(logFile, "Deleted unreferenced fossil %s\n", file)
+
+					if dryRun {
+						LOG_INFO("FOSSIL_REFERENCED", "Found referenced fossil %s", file)
+						continue
 					}
+
+					manager.chunkOperator.Resurrect(chunk, chunkDir+file)
+					fmt.Fprintf(logFile, "Found referenced fossil %s\n", file)
+
+				} else {
+
+					if dryRun {
+						LOG_INFO("FOSSIL_UNREFERENCED", "Found unreferenced fossil %s", file)
+						continue
+					}
+
+					if exclusive {
+						manager.chunkOperator.Delete(chunk, chunkDir+file)
+					} else {
+						collection.AddFossil(chunkDir + file)
+						LOG_DEBUG("FOSSIL_FIND", "Found unreferenced fossil %s", file)
+					}
+					fmt.Fprintf(logFile, "Found unreferenced fossil %s\n", file)
 				}
 			}
 
@@ -2200,7 +2347,7 @@ func (manager *SnapshotManager) pruneSnapshotsExhaustive(referencedFossils map[s
 		chunk := strings.Replace(file, "/", "", -1)
 
 		if !chunkRegex.MatchString(chunk) {
-			LOG_WARN("CHUNK_UNKONWN_FILE", "File %s is not a chunk", file)
+			LOG_WARN("CHUNK_UNKNOWN_FILE", "File %s is not a chunk", file)
 			continue
 		}
 
@@ -2210,7 +2357,7 @@ func (manager *SnapshotManager) pruneSnapshotsExhaustive(referencedFossils map[s
 				continue
 			}
 
-			manager.fossilizeChunk(chunk, chunkDir+file, exclusive, collection)
+			manager.fossilizeChunk(chunk, chunkDir+file, exclusive)
 			if exclusive {
 				fmt.Fprintf(logFile, "Deleted chunk %s (exclusive mode)\n", chunk)
 			} else {
@@ -2226,14 +2373,8 @@ func (manager *SnapshotManager) pruneSnapshotsExhaustive(referencedFossils map[s
 			}
 
 			// This is a redundant chunk file (for instance D3/495A8D and D3/49/5A8D )
-			err := manager.storage.DeleteFile(0, chunkDir+file)
-			if err != nil {
-				LOG_WARN("CHUNK_DELETE", "Failed to remove the redundant chunk file %s: %v", file, err)
-			} else {
-				LOG_TRACE("CHUNK_DELETE", "Removed the redundant chunk file %s", file)
-				fmt.Fprintf(logFile, "Deleted redundant chunk %s\n", file)
-			}
-
+			manager.chunkOperator.Delete(chunk, chunkDir+file)
+			fmt.Fprintf(logFile, "Deleted redundant chunk %s\n", file)
 		} else {
 			referencedChunks[chunk] = true
 			LOG_DEBUG("CHUNK_KEEP", "Chunk %s is referenced", chunk)
@@ -2368,7 +2509,7 @@ func (manager *SnapshotManager) DownloadFile(path string, derivationKey string)
 	}
 
 	if len(derivationKey) > 64 {
-		derivationKey = derivationKey[len(derivationKey) - 64:]
+		derivationKey = derivationKey[len(derivationKey)-64:]
 	}
 
 	err = manager.fileChunk.Decrypt(manager.config.FileKey, derivationKey)
@@ -2402,10 +2543,10 @@ func (manager *SnapshotManager) UploadFile(path string, derivationKey string, co
 	}
 
 	if len(derivationKey) > 64 {
-		derivationKey = derivationKey[len(derivationKey) - 64:]
+		derivationKey = derivationKey[len(derivationKey)-64:]
 	}
 
-	err := manager.fileChunk.Encrypt(manager.config.FileKey, derivationKey)
+	err := manager.fileChunk.Encrypt(manager.config.FileKey, derivationKey, true)
 	if err != nil {
 		LOG_ERROR("UPLOAD_File", "Failed to encrypt the file %s: %v", path, err)
 		return false

src/duplicacy_snapshotmanager_test.go

@@ -9,6 +9,7 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path"
 	"strings"
@@ -143,6 +144,15 @@ func uploadRandomChunk(manager *SnapshotManager, chunkSize int) string {
 	return uploadTestChunk(manager, content)
 }
 
+func uploadRandomChunks(manager *SnapshotManager, chunkSize int, numberOfChunks int) []string {
+	chunkList := make([]string, 0)
+	for i := 0; i < numberOfChunks; i++ {
+		chunkHash := uploadRandomChunk(manager, chunkSize)
+		chunkList = append(chunkList, chunkHash)
+	}
+	return chunkList
+}
+
 func createTestSnapshot(manager *SnapshotManager, snapshotID string, revision int, startTime int64, endTime int64, chunkHashes []string, tag string) {
 
 	snapshot := &Snapshot{
@@ -253,11 +263,11 @@ func TestPruneSingleRepository(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 4, 0)
 
 	t.Logf("Removing snapshot repository1 revisions 1 and 2 with --exclusive")
-	snapshotManager.PruneSnapshots("repository1", "repository1", []int{1, 2}, []string{}, []string{}, false, true, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{1, 2}, []string{}, []string{}, false, true, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 0)
 
 	t.Logf("Removing snapshot repository1 revision 3 without --exclusive")
-	snapshotManager.PruneSnapshots("repository1", "repository1", []int{3}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{3}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 1, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -266,7 +276,7 @@ func TestPruneSingleRepository(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Prune without removing any snapshots -- fossils will be deleted")
-	snapshotManager.PruneSnapshots("repository1", "repository1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 0)
 }
 
@@ -293,11 +303,11 @@ func TestPruneSingleHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 0)
 
 	t.Logf("Removing snapshot vm1@host1 revision 1 without --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Prune without removing any snapshots -- no fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -306,7 +316,7 @@ func TestPruneSingleHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 2)
 
 	t.Logf("Prune without removing any snapshots -- fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 3, 0)
 
 }
@@ -334,11 +344,11 @@ func TestPruneMultipleHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 0)
 
 	t.Logf("Removing snapshot vm1@host1 revision 1 without --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Prune without removing any snapshots -- no fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -347,7 +357,7 @@ func TestPruneMultipleHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 2)
 
 	t.Logf("Prune without removing any snapshots -- no fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 3, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -356,7 +366,7 @@ func TestPruneMultipleHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 4, 2)
 
 	t.Logf("Prune without removing any snapshots -- fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 4, 0)
 }
 
@@ -381,7 +391,7 @@ func TestPruneAndResurrect(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 2, 0)
 
 	t.Logf("Removing snapshot vm1@host1 revision 1 without --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 1, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -390,7 +400,7 @@ func TestPruneAndResurrect(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Prune without removing any snapshots -- one fossil will be resurrected")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 0)
 }
 
@@ -418,11 +428,11 @@ func TestPruneWithInactiveHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 0)
 
 	t.Logf("Removing snapshot vm1@host1 revision 1")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Prune without removing any snapshots -- no fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 2, 2)
 
 	t.Logf("Creating 1 snapshot")
@@ -431,7 +441,7 @@ func TestPruneWithInactiveHost(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 3, 2)
 
 	t.Logf("Prune without removing any snapshots -- fossils will be deleted")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 3, 0)
 }
 
@@ -459,15 +469,15 @@ func TestPruneWithRetentionPolicy(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 30, 0)
 
 	t.Logf("Removing snapshot vm1@host1 0:20 with --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"0:20"}, false, true, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"0:20"}, false, true, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 19, 0)
 
 	t.Logf("Removing snapshot vm1@host1 -k 0:20 with --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"0:20"}, false, true, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"0:20"}, false, true, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 19, 0)
 
 	t.Logf("Removing snapshot vm1@host1 -k 3:14 -k 2:7 with --exclusive")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"3:14", "2:7"}, false, true, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{"3:14", "2:7"}, false, true, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 12, 0)
 }
 
@@ -490,7 +500,7 @@ func TestPruneWithRetentionPolicyAndTag(t *testing.T) {
 	t.Logf("Creating 30 snapshots")
 	for i := 0; i < 30; i++ {
 		tag := "auto"
-		if i % 3 == 0 {
+		if i%3 == 0 {
 			tag = "manual"
 		}
 		createTestSnapshot(snapshotManager, "vm1@host1", i+1, now-int64(30-i)*day-3600, now-int64(30-i)*day-60, []string{chunkHashes[i]}, tag)
@@ -499,6 +509,179 @@ func TestPruneWithRetentionPolicyAndTag(t *testing.T) {
 	checkTestSnapshots(snapshotManager, 30, 0)
 
 	t.Logf("Removing snapshot vm1@host1 0:20 with --exclusive and --tag manual")
-	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{"manual"}, []string{"0:7"}, false, true, []string{}, false, false, false)
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{"manual"}, []string{"0:7"}, false, true, []string{}, false, false, false, 1)
 	checkTestSnapshots(snapshotManager, 22, 0)
 }
+
+// Test that an unreferenced fossil shouldn't be removed as it may be the result of another prune job in-progress.
+func TestPruneWithFossils(t *testing.T) {
+	setTestingT(t)
+
+	testDir := path.Join(os.TempDir(), "duplicacy_test", "snapshot_test")
+
+	snapshotManager := createTestSnapshotManager(testDir)
+
+	chunkSize := 1024
+	chunkHash1 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash2 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash3 := uploadRandomChunk(snapshotManager, chunkSize)
+	// Create an unreferenced fossil
+	snapshotManager.storage.UploadFile(0, "chunks/113b6a2350dcfd836829c47304dd330fa6b58b93dd7ac696c6b7b913e6868662.fsl", []byte("this is a test fossil"))
+
+	now := time.Now().Unix()
+	day := int64(24 * 3600)
+	t.Logf("Creating 2 snapshots")
+	createTestSnapshot(snapshotManager, "vm1@host1", 1, now-3*day-3600, now-3*day-60, []string{chunkHash1, chunkHash2}, "tag")
+	createTestSnapshot(snapshotManager, "vm1@host1", 2, now-2*day-3600, now-2*day-60, []string{chunkHash2, chunkHash3}, "tag")
+	checkTestSnapshots(snapshotManager, 2, 1)
+
+	t.Logf("Prune without removing any snapshots but with --exhaustive")
+	// The unreferenced fossil shouldn't be removed
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, true, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 2, 1)
+
+	t.Logf("Prune without removing any snapshots but with --exclusive")
+	// Now the unreferenced fossil should be removed
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, true, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 2, 0)
+}
+
+func TestPruneMultipleThread(t *testing.T) {
+
+	setTestingT(t)
+
+	testDir := path.Join(os.TempDir(), "duplicacy_test", "snapshot_test")
+
+	snapshotManager := createTestSnapshotManager(testDir)
+
+	chunkSize := 1024
+	numberOfChunks := 256
+	numberOfThreads := 4
+
+	chunkList1 := uploadRandomChunks(snapshotManager, chunkSize, numberOfChunks)
+	chunkList2 := uploadRandomChunks(snapshotManager, chunkSize, numberOfChunks)
+
+	now := time.Now().Unix()
+	day := int64(24 * 3600)
+	t.Logf("Creating 2 snapshots")
+	createTestSnapshot(snapshotManager, "repository1", 1, now-4*day-3600, now-3*day-60, chunkList1, "tag")
+	createTestSnapshot(snapshotManager, "repository1", 2, now-3*day-3600, now-2*day-60, chunkList2, "tag")
+	checkTestSnapshots(snapshotManager, 2, 0)
+
+	t.Logf("Removing snapshot revisions 1 with --exclusive")
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{1}, []string{}, []string{}, false, true, []string{}, false, false, false, numberOfThreads)
+	checkTestSnapshots(snapshotManager, 1, 0)
+
+	t.Logf("Creating 1 more snapshot")
+	chunkList3 := uploadRandomChunks(snapshotManager, chunkSize, numberOfChunks)
+	createTestSnapshot(snapshotManager, "repository1", 3, now-2*day-3600, now-1*day-60, chunkList3, "tag")
+
+	t.Logf("Removing snapshot repository1 revision 2 without --exclusive")
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{2}, []string{}, []string{}, false, false, []string{}, false, false, false, numberOfThreads)
+
+	t.Logf("Prune without removing any snapshots but with --exclusive")
+	snapshotManager.PruneSnapshots("repository1", "repository1", []int{}, []string{}, []string{}, false, true, []string{}, false, false, false, numberOfThreads)
+	checkTestSnapshots(snapshotManager, 1, 0)
+}
+
+// A snapshot not seen by a fossil collection should always be consider a new snapshot in the fossil deletion step
+func TestPruneNewSnapshots(t *testing.T) {
+	setTestingT(t)
+
+	testDir := path.Join(os.TempDir(), "duplicacy_test", "snapshot_test")
+
+	snapshotManager := createTestSnapshotManager(testDir)
+
+	chunkSize := 1024
+	chunkHash1 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash2 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash3 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash4 := uploadRandomChunk(snapshotManager, chunkSize)
+
+	now := time.Now().Unix()
+	day := int64(24 * 3600)
+	t.Logf("Creating 3 snapshots")
+	createTestSnapshot(snapshotManager, "vm1@host1", 1, now-3*day-3600, now-3*day-60, []string{chunkHash1, chunkHash2}, "tag")
+	createTestSnapshot(snapshotManager, "vm1@host1", 2, now-2*day-3600, now-2*day-60, []string{chunkHash2, chunkHash3}, "tag")
+	createTestSnapshot(snapshotManager, "vm2@host1", 1, now-2*day-3600, now-2*day-60, []string{chunkHash3, chunkHash4}, "tag")
+	checkTestSnapshots(snapshotManager, 3, 0)
+
+	t.Logf("Prune snapshot 1")
+	// chunkHash1 should be marked as fossil
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 2, 2)
+
+	chunkHash5 := uploadRandomChunk(snapshotManager, chunkSize)
+	// Create another snapshot of vm1 that brings back chunkHash1
+	createTestSnapshot(snapshotManager, "vm1@host1", 3, now-0*day-3600, now-0*day-60, []string{chunkHash1, chunkHash3}, "tag")
+	// Create another snapshot of vm2 so the fossil collection will be processed by next prune
+	createTestSnapshot(snapshotManager, "vm2@host1", 2, now+3600, now+3600*2, []string{chunkHash4, chunkHash5}, "tag")
+
+	// Now chunkHash1 wil be resurrected
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 4, 0)
+	snapshotManager.CheckSnapshots("vm1@host1", []int{2, 3}, "", false, false, false, false, false, false, 1)
+}
+
+// A fossil collection left by an aborted prune should be ignored if any supposedly deleted snapshot exists
+func TestPruneGhostSnapshots(t *testing.T) {
+	setTestingT(t)
+
+	EnableStackTrace()
+
+	testDir := path.Join(os.TempDir(), "duplicacy_test", "snapshot_test")
+
+	snapshotManager := createTestSnapshotManager(testDir)
+
+	chunkSize := 1024
+	chunkHash1 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash2 := uploadRandomChunk(snapshotManager, chunkSize)
+	chunkHash3 := uploadRandomChunk(snapshotManager, chunkSize)
+
+	now := time.Now().Unix()
+	day := int64(24 * 3600)
+	t.Logf("Creating 2 snapshots")
+	createTestSnapshot(snapshotManager, "vm1@host1", 1, now-3*day-3600, now-3*day-60, []string{chunkHash1, chunkHash2}, "tag")
+	createTestSnapshot(snapshotManager, "vm1@host1", 2, now-2*day-3600, now-2*day-60, []string{chunkHash2, chunkHash3}, "tag")
+	checkTestSnapshots(snapshotManager, 2, 0)
+
+	snapshot1, err := ioutil.ReadFile(path.Join(testDir, "snapshots", "vm1@host1", "1"))
+	if err != nil {
+		t.Errorf("Failed to read snapshot file: %v", err)
+	}
+
+	t.Logf("Prune snapshot 1")
+	// chunkHash1 should be marked as fossil
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 1, 2)
+
+	// Recover the snapshot file for revision 1; this is to simulate a scenario where prune may encounter a network error after
+	// leaving the fossil collection but before deleting any snapshots.
+	err = ioutil.WriteFile(path.Join(testDir, "snapshots", "vm1@host1", "1"), snapshot1, 0644)
+	if err != nil {
+		t.Errorf("Failed to write snapshot file: %v", err)
+	}
+
+	// Create another snapshot of vm1 so the fossil collection becomes eligible for processing.
+	chunkHash4 := uploadRandomChunk(snapshotManager, chunkSize)
+	createTestSnapshot(snapshotManager, "vm1@host1", 3, now-day-3600, now-day-60, []string{chunkHash3, chunkHash4}, "tag")
+
+	// Run the prune again but the fossil collection should be igored, since revision 1 still exists
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 3, 2)
+	snapshotManager.CheckSnapshots("vm1@host1", []int{1, 2, 3}, "", false, false, false, false, true /*searchFossils*/, false, 1)
+
+	// Prune snapshot 1 again
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{1}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 2, 2)
+
+	// Create another snapshot
+	chunkHash5 := uploadRandomChunk(snapshotManager, chunkSize)
+	createTestSnapshot(snapshotManager, "vm1@host1", 4, now+3600, now+3600*2, []string{chunkHash5, chunkHash5}, "tag")
+	checkTestSnapshots(snapshotManager, 3, 2)
+
+	// Run the prune again and this time the fossil collection will be processed and the fossils removed
+	snapshotManager.PruneSnapshots("vm1@host1", "vm1@host1", []int{}, []string{}, []string{}, false, false, []string{}, false, false, false, 1)
+	checkTestSnapshots(snapshotManager, 3, 0)
+	snapshotManager.CheckSnapshots("vm1@host1", []int{2, 3, 4}, "", false, false, false, false, false, false, 1)
+}

src/duplicacy_storage.go

@@ -89,7 +89,7 @@ func (storage *StorageBase) SetRateLimits(downloadRateLimit int, uploadRateLimit
 }
 
 // SetDefaultNestingLevels sets the default read and write levels.  This is usually called by
-// derived storages to set the levels with old values so that storages initialied by ealier versions
+// derived storages to set the levels with old values so that storages initialized by earlier versions
 // will continue to work.
 func (storage *StorageBase) SetDefaultNestingLevels(readLevels []int, writeLevel int) {
 	storage.readLevels = readLevels
@@ -268,7 +268,7 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 	if matched == nil {
 		LOG_ERROR("STORAGE_CREATE", "Unrecognizable storage URL: %s", storageURL)
 		return nil
-	} else if matched[1] == "sftp" {
+	} else if matched[1] == "sftp" || matched[1] == "sftpc" {
 		server := matched[3]
 		username := matched[2]
 		storageDir := matched[5]
@@ -291,6 +291,7 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 
 		// If ssh_key_file is set, skip password-based login
 		keyFile := GetPasswordFromPreference(preference, "ssh_key_file")
+		passphrase := ""
 
 		password := ""
 		passwordCallback := func() (string, error) {
@@ -335,7 +336,7 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 			keyFile = GetPassword(preference, "ssh_key_file", "Enter the path of the private key file:",
 				true, resetPassword)
 
-			var key ssh.Signer
+			var keySigner ssh.Signer
 			var err error
 
 			if keyFile == "" {
@@ -346,15 +347,52 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 				if err != nil {
 					LOG_INFO("SSH_PUBLICKEY", "Failed to read the private key file: %v", err)
 				} else {
-					key, err = ssh.ParsePrivateKey(content)
+					keySigner, err = ssh.ParsePrivateKey(content)
 					if err != nil {
-						LOG_INFO("SSH_PUBLICKEY", "Failed to parse the private key file %s: %v", keyFile, err)
+						if _, ok := err.(*ssh.PassphraseMissingError); ok {
+							LOG_TRACE("SSH_PUBLICKEY", "The private key file is encrypted")
+							passphrase = GetPassword(preference, "ssh_passphrase", "Enter the passphrase to decrypt the private key file:", false, resetPassword)
+							if len(passphrase) == 0 {
+								LOG_INFO("SSH_PUBLICKEY", "No passphrase to descrypt the private key file %s", keyFile)
+							} else {
+								keySigner, err = ssh.ParsePrivateKeyWithPassphrase(content, []byte(passphrase))
+								if err != nil {
+									LOG_INFO("SSH_PUBLICKEY", "Failed to parse the encrypted private key file %s: %v", keyFile, err)
+								}
+							}
+						} else {
+							LOG_INFO("SSH_PUBLICKEY", "Failed to parse the private key file %s: %v", keyFile, err)
+						}
+					}
+
+					if keySigner != nil {
+						certFile := keyFile + "-cert.pub"
+						if stat, err := os.Stat(certFile); err == nil && !stat.IsDir() {
+							LOG_DEBUG("SSH_CERTIFICATE", "Attempting to use ssh certificate from file %s", certFile)
+							var content []byte
+							content, err = ioutil.ReadFile(certFile)
+							if err != nil {
+								LOG_INFO("SSH_CERTIFICATE", "Failed to read ssh certificate file %s: %v", certFile, err)
+							} else {
+								pubKey, _, _, _, err := ssh.ParseAuthorizedKey(content)
+								if err != nil {
+									LOG_INFO("SSH_CERTIFICATE", "Failed parse ssh certificate file %s: %v", certFile, err)
+								} else {
+									certSigner, err := ssh.NewCertSigner(pubKey.(*ssh.Certificate), keySigner)
+									if err != nil {
+										LOG_INFO("SSH_CERTIFICATE", "Failed to create certificate signer: %v", err)
+									} else {
+										keySigner = certSigner
+									}
+								}
+							}
+						}
 					}
 				}
 			}
 
-			if key != nil {
-				signers = append(signers, key)
+			if keySigner != nil {
+				signers = append(signers, keySigner)
 			}
 
 			if len(signers) > 0 {
@@ -402,7 +440,7 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 			return checkHostKey(hostname, remote, key)
 		}
 
-		sftpStorage, err := CreateSFTPStorage(server, port, username, storageDir, 2, authMethods, hostKeyChecker, threads)
+		sftpStorage, err := CreateSFTPStorage(matched[1] == "sftpc", server, port, username, storageDir, 2, authMethods, hostKeyChecker, threads)
 		if err != nil {
 			LOG_ERROR("STORAGE_CREATE", "Failed to load the SFTP storage at %s: %v", storageURL, err)
 			return nil
@@ -410,6 +448,9 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 
 		if keyFile != "" {
 			SavePassword(preference, "ssh_key_file", keyFile)
+			if passphrase != "" {
+				SavePassword(preference, "ssh_passphrase", passphrase)
+			}
 		} else if password != "" {
 			SavePassword(preference, "ssh_password", password)
 		}
@@ -509,11 +550,30 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 		return dropboxStorage
 	} else if matched[1] == "b2" {
 		bucket := matched[3]
+		storageDir := matched[5]
 
-		accountID := GetPassword(preference, "b2_id", "Enter Backblaze Account ID:", true, resetPassword)
-		applicationKey := GetPassword(preference, "b2_key", "Enter Backblaze Application Key:", true, resetPassword)
+		accountID := GetPassword(preference, "b2_id", "Enter Backblaze account or application id:", true, resetPassword)
+		applicationKey := GetPassword(preference, "b2_key", "Enter corresponding Backblaze application key:", true, resetPassword)
 
-		b2Storage, err := CreateB2Storage(accountID, applicationKey, bucket, threads)
+		b2Storage, err := CreateB2Storage(accountID, applicationKey, "", bucket, storageDir, threads)
+		if err != nil {
+			LOG_ERROR("STORAGE_CREATE", "Failed to load the Backblaze B2 storage at %s: %v", storageURL, err)
+			return nil
+		}
+		SavePassword(preference, "b2_id", accountID)
+		SavePassword(preference, "b2_key", applicationKey)
+		return b2Storage
+	} else if matched[1] == "b2-custom" {
+		b2customUrlRegex := regexp.MustCompile(`^b2-custom://([^/]+)/([^/]+)(/(.+))?`)
+		matched := b2customUrlRegex.FindStringSubmatch(storageURL)
+		downloadURL := "https://" + matched[1]
+		bucket := matched[2]
+		storageDir := matched[4]
+
+		accountID := GetPassword(preference, "b2_id", "Enter Backblaze account or application id:", true, resetPassword)
+		applicationKey := GetPassword(preference, "b2_key", "Enter corresponding Backblaze application key:", true, resetPassword)
+
+		b2Storage, err := CreateB2Storage(accountID, applicationKey, downloadURL, bucket, storageDir, threads)
 		if err != nil {
 			LOG_ERROR("STORAGE_CREATE", "Failed to load the Backblaze B2 storage at %s: %v", storageURL, err)
 			return nil
@@ -564,26 +624,35 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 		SavePassword(preference, "gcs_token", tokenFile)
 		return gcsStorage
 	} else if matched[1] == "gcd" {
+		// Handle writing directly to the root of the drive
+		// For gcd://driveid@/, driveid@ is match[3] not match[2]
+		if matched[2] == "" && strings.HasSuffix(matched[3], "@") {
+			matched[2], matched[3]  = matched[3], matched[2]
+		}
+		driveID := matched[2]
+		if driveID != "" {
+			driveID = driveID[:len(driveID)-1]
+		}
 		storagePath := matched[3] + matched[4]
 		prompt := fmt.Sprintf("Enter the path of the Google Drive token file (downloadable from https://duplicacy.com/gcd_start):")
 		tokenFile := GetPassword(preference, "gcd_token", prompt, true, resetPassword)
-		gcdStorage, err := CreateGCDStorage(tokenFile, storagePath, threads)
+		gcdStorage, err := CreateGCDStorage(tokenFile, driveID, storagePath, threads)
 		if err != nil {
 			LOG_ERROR("STORAGE_CREATE", "Failed to load the Google Drive storage at %s: %v", storageURL, err)
 			return nil
 		}
 		SavePassword(preference, "gcd_token", tokenFile)
 		return gcdStorage
-	} else if matched[1] == "one" {
+	} else if matched[1] == "one" || matched[1] == "odb" {
 		storagePath := matched[3] + matched[4]
 		prompt := fmt.Sprintf("Enter the path of the OneDrive token file (downloadable from https://duplicacy.com/one_start):")
-		tokenFile := GetPassword(preference, "one_token", prompt, true, resetPassword)
-		oneDriveStorage, err := CreateOneDriveStorage(tokenFile, storagePath, threads)
+		tokenFile := GetPassword(preference, matched[1] + "_token", prompt, true, resetPassword)
+		oneDriveStorage, err := CreateOneDriveStorage(tokenFile, matched[1] == "odb", storagePath, threads)
 		if err != nil {
 			LOG_ERROR("STORAGE_CREATE", "Failed to load the OneDrive storage at %s: %v", storageURL, err)
 			return nil
 		}
-		SavePassword(preference, "one_token", tokenFile)
+		SavePassword(preference, matched[1] + "_token", tokenFile)
 		return oneDriveStorage
 	} else if matched[1] == "hubic" {
 		storagePath := matched[3] + matched[4]
@@ -609,7 +678,11 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 	} else if matched[1] == "webdav" || matched[1] == "webdav-http" {
 		server := matched[3]
 		username := matched[2]
-		username = username[:len(username) - 1]
+		if username == "" {
+			LOG_ERROR("STORAGE_CREATE", "No username is provided to access the WebDAV storage")
+			return nil
+		}
+		username = username[:len(username)-1]
 		storageDir := matched[5]
 		port := 0
 		useHTTP := matched[1] == "webdav-http"
@@ -629,6 +702,18 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 		}
 		SavePassword(preference, "webdav_password", password)
 		return webDAVStorage
+	} else if matched[1] == "fabric" {
+		endpoint := matched[3]
+		storageDir := matched[5]
+		prompt := fmt.Sprintf("Enter the token for accessing the Storage Made Easy File Fabric storage:")
+		token := GetPassword(preference, "fabric_token", prompt, true, resetPassword)
+		smeStorage, err := CreateFileFabricStorage(endpoint, token, storageDir, threads)
+		if err != nil {
+			LOG_ERROR("STORAGE_CREATE", "Failed to load the File Fabric storage at %s: %v", storageURL, err)
+			return nil
+		}
+		SavePassword(preference, "fabric_token", token)
+		return smeStorage
 	} else {
 		LOG_ERROR("STORAGE_CREATE", "The storage type '%s' is not supported", matched[1])
 		return nil

src/duplicacy_storage_test.go

@@ -27,6 +27,8 @@ var testRateLimit int
 var testQuickMode bool
 var testThreads int
 var testFixedChunkSize bool
+var testRSAEncryption bool
+var testErasureCoding bool
 
 func init() {
 	flag.StringVar(&testStorageName, "storage", "", "the test storage to use")
@@ -34,6 +36,8 @@ func init() {
 	flag.BoolVar(&testQuickMode, "quick", false, "quick test")
 	flag.IntVar(&testThreads, "threads", 1, "number of downloading/uploading threads")
 	flag.BoolVar(&testFixedChunkSize, "fixed-chunk-size", false, "fixed chunk size")
+	flag.BoolVar(&testRSAEncryption, "rsa", false, "enable RSA encryption")
+	flag.BoolVar(&testErasureCoding, "erasure-coding", false, "enable Erasure Coding")
 	flag.Parse()
 }
 
@@ -80,12 +84,12 @@ func loadStorage(localStoragePath string, threads int) (Storage, error) {
 		return storage, err
 	} else if testStorageName == "s3" {
 		storage, err := CreateS3Storage(config["region"], config["endpoint"], config["bucket"], config["directory"], config["access_key"], config["secret_key"], threads, true, false)
-		return storage, err
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
 	} else if testStorageName == "wasabi" {
 		storage, err := CreateWasabiStorage(config["region"], config["endpoint"], config["bucket"], config["directory"], config["access_key"], config["secret_key"], threads)
-		return storage, err
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
 	} else if testStorageName == "s3c" {
 		storage, err := CreateS3CStorage(config["region"], config["endpoint"], config["bucket"], config["directory"], config["access_key"], config["secret_key"], threads)
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
@@ -107,7 +111,7 @@ func loadStorage(localStoragePath string, threads int) (Storage, error) {
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
 	} else if testStorageName == "b2" {
-		storage, err := CreateB2Storage(config["account"], config["key"], config["bucket"], threads)
+		storage, err := CreateB2Storage(config["account"], config["key"], "", config["bucket"], config["directory"], threads)
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
 	} else if testStorageName == "gcs-s3" {
@@ -131,11 +135,23 @@ func loadStorage(localStoragePath string, threads int) (Storage, error) {
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
 	} else if testStorageName == "gcd" {
-		storage, err := CreateGCDStorage(config["token_file"], config["storage_path"], threads)
+		storage, err := CreateGCDStorage(config["token_file"], "", config["storage_path"], threads)
+		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
+	} else if testStorageName == "gcd-shared" {
+		storage, err := CreateGCDStorage(config["token_file"], config["drive"], config["storage_path"], threads)
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
 	} else if testStorageName == "one" {
-		storage, err := CreateOneDriveStorage(config["token_file"], config["storage_path"], threads)
+		storage, err := CreateOneDriveStorage(config["token_file"], false, config["storage_path"], threads)
+		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
+	} else if testStorageName == "odb" {
+		storage, err := CreateOneDriveStorage(config["token_file"], true, config["storage_path"], threads)
+		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
+	} else if testStorageName == "one" {
+		storage, err := CreateOneDriveStorage(config["token_file"], false, config["storage_path"], threads)
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
 	} else if testStorageName == "hubic" {
@@ -153,10 +169,7 @@ func loadStorage(localStoragePath string, threads int) (Storage, error) {
 		}
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
-	} else {
-		return nil, fmt.Errorf("Invalid storage named: %s", testStorageName)
 	}
-
 	return nil, fmt.Errorf("Invalid storage named: %s", testStorageName)
 }
 
@@ -299,7 +312,8 @@ func TestStorage(t *testing.T) {
 
 	LOG_INFO("STORAGE_TEST", "storage: %s", testStorageName)
 
-	storage, err := loadStorage(testDir, 1)
+	threads := 8
+	storage, err := loadStorage(testDir, threads)
 	if err != nil {
 		t.Errorf("Failed to create storage: %v", err)
 		return
@@ -329,16 +343,16 @@ func TestStorage(t *testing.T) {
 	storage.CreateDirectory(0, "shared")
 
 	// Upload to the same directory by multiple goroutines
-	count := 8
+	count := threads
 	finished := make(chan int, count)
 	for i := 0; i < count; i++ {
-		go func(name string) {
-			err := storage.UploadFile(0, name, []byte("this is a test file"))
+		go func(threadIndex int, name string) {
+			err := storage.UploadFile(threadIndex, name, []byte("this is a test file"))
 			if err != nil {
 				t.Errorf("Error to upload '%s': %v", name, err)
 			}
 			finished <- 0
-		}(fmt.Sprintf("shared/a/b/c/%d", i))
+		}(i, fmt.Sprintf("shared/a/b/c/%d", i))
 	}
 
 	for i := 0; i < count; i++ {
@@ -387,7 +401,6 @@ func TestStorage(t *testing.T) {
 
 	snapshotIDs := []string{}
 	for _, snapshotDir := range snapshotDirs {
-		LOG_INFO("debug", "snapshot dir: %s", snapshotDir)
 		if len(snapshotDir) > 0 && snapshotDir[len(snapshotDir)-1] == '/' {
 			snapshotIDs = append(snapshotIDs, snapshotDir[:len(snapshotDir)-1])
 		}
@@ -514,7 +527,7 @@ func TestStorage(t *testing.T) {
 	} else {
 		err = storage.DeleteFile(0, filePath)
 		if err != nil {
-			t.Errorf("Failed to delete file %s: %v", filePath)
+			t.Errorf("Failed to delete file %s: %v", filePath, err)
 		} else {
 			time.Sleep(time.Duration(delay) * time.Second)
 			filePath, exist, _, err = storage.FindChunk(0, chunks[1], true)

src/duplicacy_swiftstorage.go

@@ -21,7 +21,7 @@ type SwiftStorage struct {
 	threads    int
 }
 
-// CreateSwiftStorage creates an OpenStack Swift storage object.  storageURL is in the form of 
+// CreateSwiftStorage creates an OpenStack Swift storage object.  storageURL is in the form of
 // `user@authURL/container/path?arg1=value1&arg2=value2``
 func CreateSwiftStorage(storageURL string, key string, threads int) (storage *SwiftStorage, err error) {
 

src/duplicacy_utils.go

@@ -10,10 +10,7 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path"
-	"path/filepath"
 	"regexp"
-	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -58,7 +55,7 @@ func IsEmptyFilter(pattern string) bool {
 }
 
 func IsUnspecifiedFilter(pattern string) bool {
-	if pattern[0] != '+' && pattern[0] != '-' && pattern[0] != 'i' && pattern[0] != 'e' {
+	if pattern[0] != '+' && pattern[0] != '-' && !strings.HasPrefix(pattern, "i:") && !strings.HasPrefix(pattern, "e:")  {
 		return true
 	} else {
 		return false
@@ -176,6 +173,15 @@ func GetPasswordFromPreference(preference Preference, passwordType string) strin
 		if password, found := os.LookupEnv(name); found && password != "" {
 			return password
 		}
+
+		re := regexp.MustCompile(`[^a-zA-Z0-9_]`)
+		namePlain := re.ReplaceAllString(name, "_")
+		if namePlain != name {
+			LOG_DEBUG("PASSWORD_ENV_VAR", "Reading the environment variable %s", namePlain)
+			if password, found := os.LookupEnv(namePlain); found && password != "" {
+				return password
+			}
+		}
 	}
 
 	// If the password is stored in the preference, there is no need to include the storage name
@@ -344,11 +350,13 @@ func MatchPath(filePath string, patterns []string) (included bool) {
 	for _, pattern := range patterns {
 		if pattern[0] == '+' {
 			if matchPattern(filePath, pattern[1:]) {
+				LOG_DEBUG("PATTERN_INCLUDE", "%s is included by pattern %s", filePath, pattern)
 				return true
 			}
 		} else if pattern[0] == '-' {
 			allIncludes = false
 			if matchPattern(filePath, pattern[1:]) {
+				LOG_DEBUG("PATTERN_EXCLUDE", "%s is excluded by pattern %s", filePath, pattern)
 				return false
 			}
 		} else if strings.HasPrefix(pattern, "i:") || strings.HasPrefix(pattern, "e:") {
@@ -363,7 +371,14 @@ func MatchPath(filePath string, patterns []string) (included bool) {
 				matched = re.MatchString(filePath)
 			}
 			if matched {
-				return strings.HasPrefix(pattern, "i:")
+				if strings.HasPrefix(pattern, "i:") {
+					LOG_DEBUG("PATTERN_INCLUDE", "%s is included by pattern %s", filePath, pattern)
+					return true
+				} else {
+					LOG_DEBUG("PATTERN_EXCLUDE", "%s is excluded by pattern %s", filePath, pattern)
+					return false
+
+				}
 			} else {
 				if strings.HasPrefix(pattern, "e:") {
 					allIncludes = false
@@ -372,20 +387,13 @@ func MatchPath(filePath string, patterns []string) (included bool) {
 		}
 	}
 
-	return !allIncludes
-}
-
-func joinPath(components ...string) string {
-
-	combinedPath := path.Join(components...)
-	if len(combinedPath) > 257 && runtime.GOOS == "windows" {
-		combinedPath = `\\?\` + filepath.Join(components...)
-		// If the path is on a samba drive we must use the UNC format
-		if strings.HasPrefix(combinedPath, `\\?\\\`) {
-			combinedPath = `\\?\UNC\` + combinedPath[6:]
-		}
+	if allIncludes {
+		LOG_DEBUG("PATTERN_EXCLUDE", "%s is excluded", filePath)
+		return false
+	} else {
+		LOG_DEBUG("PATTERN_INCLUDE", "%s is included", filePath)
+		return true
 	}
-	return combinedPath
 }
 
 func PrettyNumber(number int64) string {
@@ -452,10 +460,3 @@ func AtoSize(sizeString string) int {
 
 	return size
 }
-
-func MinInt(x, y int) int {
-	if x < y {
-		return x
-	}
-	return y
-}

src/duplicacy_utils_others.go

@@ -9,6 +9,7 @@ package duplicacy
 import (
 	"bytes"
 	"os"
+	"path"
 	"path/filepath"
 	"syscall"
 
@@ -35,7 +36,7 @@ func SetOwner(fullPath string, entry *Entry, fileInfo *os.FileInfo) bool {
 	stat, ok := (*fileInfo).Sys().(*syscall.Stat_t)
 	if ok && stat != nil && (int(stat.Uid) != entry.UID || int(stat.Gid) != entry.GID) {
 		if entry.UID != -1 && entry.GID != -1 {
-			err := os.Chown(fullPath, entry.UID, entry.GID)
+			err := os.Lchown(fullPath, entry.UID, entry.GID)
 			if err != nil {
 				LOG_ERROR("RESTORE_CHOWN", "Failed to change uid or gid: %v", err)
 				return false
@@ -83,3 +84,11 @@ func (entry *Entry) SetAttributesToFile(fullPath string) {
 	}
 
 }
+
+func joinPath(components ...string) string {
+	return path.Join(components...)
+}
+
+func SplitDir(fullPath string) (dir string, file string) {
+	return path.Split(fullPath)
+}

src/duplicacy_utils_test.go

@@ -92,6 +92,17 @@ func TestMatchPattern(t *testing.T) {
 		}
 	}
 
+	for _, pattern := range []string{ "+", "-", "i:", "e:", "+a", "-a", "i:a", "e:a"} {
+		if IsUnspecifiedFilter(pattern) {
+			t.Errorf("pattern %s has a specified filter", pattern)
+		}
+	}
+
+	for _, pattern := range []string{ "i", "e", "ia", "ib", "a", "b"} {
+		if !IsUnspecifiedFilter(pattern) {
+			t.Errorf("pattern %s does not have a specified filter", pattern)
+		}
+	}
 }
 
 func TestRateLimit(t *testing.T) {
@@ -112,7 +123,7 @@ func TestRateLimit(t *testing.T) {
 		return
 	}
 	if int(n) != len(content) {
-		t.Errorf("Wrote %s bytes instead of %s", n, len(content))
+		t.Errorf("Wrote %d bytes instead of %d", n, len(content))
 		return
 	}
 
@@ -127,7 +138,7 @@ func TestRateLimit(t *testing.T) {
 		return
 	}
 	if int(n) != len(content) {
-		t.Errorf("Copied %s bytes instead of %s", n, len(content))
+		t.Errorf("Copied %d bytes instead of %d", n, len(content))
 		return
 	}
 

src/duplicacy_utils_windows.go

@@ -7,6 +7,8 @@ package duplicacy
 import (
 	"fmt"
 	"os"
+	"path/filepath"
+	"strings"
 	"syscall"
 	"unsafe"
 )
@@ -114,3 +116,18 @@ func (entry *Entry) ReadAttributes(top string) {
 func (entry *Entry) SetAttributesToFile(fullPath string) {
 
 }
+
+func joinPath(components ...string) string {
+
+	combinedPath := `\\?\` + filepath.Join(components...)
+	// If the path is on a samba drive we must use the UNC format
+	if strings.HasPrefix(combinedPath, `\\?\\\`) {
+		combinedPath = `\\?\UNC\` + combinedPath[6:]
+	}
+	return combinedPath
+}
+
+func SplitDir(fullPath string) (dir string, file string) {
+	i := strings.LastIndex(fullPath, "\\")
+	return fullPath[:i+1], fullPath[i+1:]
+}

src/duplicacy_wasabistorage.go

@@ -93,43 +93,49 @@ func (storage *WasabiStorage) DeleteFile(
 // rename.  It's designed to get the job done with as few dependencies
 // on other packages as possible rather than being somethng
 // general-purpose and reusable.
-func (storage *WasabiStorage) MoveFile(
-	threadIndex int, from string, to string,
-) (err error) {
+func (storage *WasabiStorage) MoveFile(threadIndex int, from string, to string) (err error) {
 
-	// The from path includes the bucket
-	from_path := fmt.Sprintf("/%s/%s/%s", storage.bucket, storage.storageDir, from)
+	var fromPath string
+	// The from path includes the bucket.  Take care not to include an empty storageDir
+	// string as Wasabi's backend will return 404 on URLs with double slashes.
+	if storage.storageDir == "" {
+		fromPath = fmt.Sprintf("/%s/%s", storage.bucket, from)
+	} else {
+		fromPath = fmt.Sprintf("/%s/%s/%s", storage.bucket, storage.storageDir, from)
+	}
 
-	object := fmt.Sprintf("https://%s@%s%s",
-		storage.region, storage.endpoint, from_path)
+	object := fmt.Sprintf("https://%s@%s%s", storage.region, storage.endpoint, fromPath)
 
+	toPath := to
 	// The object's new name is relative to the top of the bucket.
-	new_name := fmt.Sprintf("%s/%s", storage.storageDir, to)
+	if storage.storageDir != "" {
+		toPath = fmt.Sprintf("%s/%s", storage.storageDir, to)
+	}
 
 	timestamp := time.Now().Format(time.RFC1123Z)
 
-	signing_string := fmt.Sprintf("MOVE\n\n\n%s\n%s", timestamp, from_path)
+	signingString := fmt.Sprintf("MOVE\n\n\n%s\n%s", timestamp, fromPath)
 
 	signer := hmac.New(sha1.New, []byte(storage.secret))
-	signer.Write([]byte(signing_string))
+	signer.Write([]byte(signingString))
 
 	signature := base64.StdEncoding.EncodeToString(signer.Sum(nil))
 
 	authorization := fmt.Sprintf("AWS %s:%s", storage.key, signature)
 
-	request, error := http.NewRequest("MOVE", object, nil)
-	if error != nil {
-		return error
+	request, err := http.NewRequest("MOVE", object, nil)
+	if err != nil {
+		return err
 	}
 	request.Header.Add("Authorization", authorization)
 	request.Header.Add("Date", timestamp)
-	request.Header.Add("Destination", new_name)
+	request.Header.Add("Destination", toPath)
 	request.Header.Add("Host", storage.endpoint)
 	request.Header.Add("Overwrite", "true")
 
-	response, error := storage.client.Do(request)
-	if error != nil {
-		return error
+	response, err := storage.client.Do(request)
+	if err != nil {
+		return err
 	}
 	defer response.Body.Close()
 

src/duplicacy_webdavstorage.go

@@ -14,15 +14,13 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math/rand"
 	"net/http"
 	//"net/http/httputil"
-	"path/filepath"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
-	"strings"
 )
 
 type WebDAVStorage struct {
@@ -43,14 +41,14 @@ type WebDAVStorage struct {
 
 var (
 	errWebDAVAuthorizationFailure = errors.New("Authentication failed")
-	errWebDAVMovedPermanently = errors.New("Moved permanently")
-	errWebDAVNotExist = errors.New("Path does not exist")
-	errWebDAVMaximumBackoff = errors.New("Maximum backoff reached")
-	errWebDAVMethodNotAllowed = errors.New("Method not allowed")
+	errWebDAVMovedPermanently     = errors.New("Moved permanently")
+	errWebDAVNotExist             = errors.New("Path does not exist")
+	errWebDAVMaximumBackoff       = errors.New("Maximum backoff reached")
+	errWebDAVMethodNotAllowed     = errors.New("Method not allowed")
 )
 
 func CreateWebDAVStorage(host string, port int, username string, password string, storageDir string, useHTTP bool, threads int) (storage *WebDAVStorage, err error) {
-	if storageDir[len(storageDir)-1] != '/' {
+	if len(storageDir) > 0 && storageDir[len(storageDir)-1] != '/' {
 		storageDir += "/"
 	}
 
@@ -60,7 +58,7 @@ func CreateWebDAVStorage(host string, port int, username string, password string
 		username:   username,
 		password:   password,
 		storageDir: "",
-		useHTTP:    false,
+		useHTTP:    useHTTP,
 
 		client:         http.DefaultClient,
 		threads:        threads,
@@ -69,7 +67,7 @@ func CreateWebDAVStorage(host string, port int, username string, password string
 
 	// Make sure it doesn't follow redirect
 	storage.client.CheckRedirect = func(req *http.Request, via []*http.Request) error {
-        return http.ErrUseLastResponse
+		return http.ErrUseLastResponse
 	}
 
 	exist, isDir, _, err := storage.GetFileInfo(0, storageDir)
@@ -152,6 +150,10 @@ func (storage *WebDAVStorage) sendRequest(method string, uri string, depth int,
 			request.Header.Set(key, value)
 		}
 
+		if method == "PUT" {
+			request.ContentLength = int64(len(data))
+		}
+
 		//requestDump, err := httputil.DumpRequest(request, true)
 		//LOG_INFO("debug", "Request: %s", requestDump)
 
@@ -211,53 +213,56 @@ type WebDAVMultiStatus struct {
 
 func (storage *WebDAVStorage) getProperties(uri string, depth int, properties ...string) (map[string]WebDAVProperties, error) {
 
-	propfind := "<prop>"
-	for _, p := range properties {
-		propfind += fmt.Sprintf("<%s/>", p)
-	}
-	propfind += "</prop>"
+	maxTries := 3
+	for tries := 0; ; tries++ {
+		propfind := "<prop>"
+		for _, p := range properties {
+			propfind += fmt.Sprintf("<%s/>", p)
+		}
+		propfind += "</prop>"
 
-	body := fmt.Sprintf(`<?xml version="1.0" encoding="utf-8" ?><propfind xmlns="DAV:">%s</propfind>`, propfind)
+		body := fmt.Sprintf(`<?xml version="1.0" encoding="utf-8" ?><propfind xmlns="DAV:">%s</propfind>`, propfind)
 
-	readCloser, _, err := storage.sendRequest("PROPFIND", uri, depth, []byte(body))
-	if err != nil {
-		return nil, err
-	}
-	defer readCloser.Close()
-	content, err := ioutil.ReadAll(readCloser)
-	if err != nil {
-		return nil, err
-	}
+		readCloser, _, err := storage.sendRequest("PROPFIND", uri, depth, []byte(body))
+		if err != nil {
+			return nil, err
+		}
+		defer readCloser.Close()
 
-	object := WebDAVMultiStatus{}
-	err = xml.Unmarshal(content, &object)
-	if err != nil {
-		return nil, err
-	}
-
-	if object.Responses == nil || len(object.Responses) == 0 {
-		return nil, errors.New("no WebDAV responses")
-	}
-
-	responses := make(map[string]WebDAVProperties)
-
-	for _, responseTag := range object.Responses {
-
-		if responseTag.PropStat == nil || responseTag.PropStat.Prop == nil || responseTag.PropStat.Prop.PropList == nil {
-			return nil, errors.New("no WebDAV properties")
+		object := WebDAVMultiStatus{}
+		err = xml.NewDecoder(readCloser).Decode(&object)
+		if err != nil {
+			if strings.Contains(err.Error(), "unexpected EOF") && tries < maxTries {
+				LOG_WARN("WEBDAV_RETRY", "Retrying on %v", err)
+				continue
+			}
+			return nil, err
 		}
 
-		properties := make(WebDAVProperties)
-		for _, prop := range responseTag.PropStat.Prop.PropList {
-			properties[prop.XMLName.Local] = prop.Value
+		if object.Responses == nil || len(object.Responses) == 0 {
+			return nil, errors.New("no WebDAV responses")
 		}
 
-		responseKey := responseTag.Href
-		responses[responseKey] = properties
+		responses := make(map[string]WebDAVProperties)
 
+		for _, responseTag := range object.Responses {
+
+			if responseTag.PropStat == nil || responseTag.PropStat.Prop == nil || responseTag.PropStat.Prop.PropList == nil {
+				return nil, errors.New("no WebDAV properties")
+			}
+
+			properties := make(WebDAVProperties)
+			for _, prop := range responseTag.PropStat.Prop.PropList {
+				properties[prop.XMLName.Local] = prop.Value
+			}
+
+			responseKey := responseTag.Href
+			responses[responseKey] = properties
+
+		}
+
+		return responses, nil
 	}
-
-	return responses, nil
 }
 
 // ListFiles return the list of files and subdirectories under 'dir'.  A subdirectories returned must have a trailing '/', with
@@ -314,6 +319,7 @@ func (storage *WebDAVStorage) ListFiles(threadIndex int, dir string) (files []st
 
 // GetFileInfo returns the information about the file or directory at 'filePath'.
 func (storage *WebDAVStorage) GetFileInfo(threadIndex int, filePath string) (exist bool, isDir bool, size int64, err error) {
+
 	properties, err := storage.getProperties(filePath, 0, "getcontentlength", "resourcetype")
 	if err != nil {
 		if err == errWebDAVNotExist {
@@ -326,11 +332,18 @@ func (storage *WebDAVStorage) GetFileInfo(threadIndex int, filePath string) (exi
 		return false, false, 0, err
 	}
 
-	if m, exist := properties["/" + storage.storageDir + filePath]; !exist {
+	m, exist := properties["/"+storage.storageDir+filePath]
+
+	// If no properties exist for the given filePath, remove the trailing / from filePath and search again
+	if !exist && filePath != "" && filePath[len(filePath) - 1] == '/' {
+		m, exist = properties["/"+storage.storageDir+filePath[:len(filePath) - 1]]
+	}
+
+	if !exist {
 		return false, false, 0, nil
 	} else if resourceType, exist := m["resourcetype"]; exist && strings.Contains(resourceType, "collection") {
 		return true, true, 0, nil
-	} else if length, exist := m["getcontentlength"]; exist && length != ""{
+	} else if length, exist := m["getcontentlength"]; exist && length != "" {
 		value, _ := strconv.Atoi(length)
 		return true, false, int64(value), nil
 	} else {
@@ -360,11 +373,12 @@ func (storage *WebDAVStorage) MoveFile(threadIndex int, from string, to string)
 
 // createParentDirectory creates the parent directory if it doesn't exist in the cache
 func (storage *WebDAVStorage) createParentDirectory(threadIndex int, dir string) (err error) {
-	parent := filepath.Dir(dir)
 
-	if parent == "." {
+	found := strings.LastIndex(dir, "/")
+	if found == -1 {
 		return nil
 	}
+	parent := dir[:found]
 
 	storage.directoryCacheLock.Lock()
 	_, exist := storage.directoryCache[parent]