librclone: add PHP bindings and test program

librclone/php/rclone.php

@@ -0,0 +1,53 @@
+<?php
+/*
+PHP interface to librclone.so, using FFI ( Foreign Function Interface )
+
+Create an rclone object
+
+$rc = new Rclone( __DIR__ . '/librclone.so' );
+
+Then call rpc calls on it
+
+    $rc->rpc( "config/listremotes", "{}" );
+
+When finished, close it
+
+    $rc->close();
+*/
+
+class Rclone {
+
+    protected $rclone;
+    private $out;
+
+    public function __construct( $libshared )
+    {
+        $this->rclone = \FFI::cdef("
+        struct RcloneRPCResult {
+            char* Output;
+            int	Status;
+        };        
+        extern void RcloneInitialize();
+        extern void RcloneFinalize();
+        extern struct RcloneRPCResult RcloneRPC(char* method, char* input);
+        extern void RcloneFreeString(char* str);
+        ", $libshared);
+        $this->rclone->RcloneInitialize();
+    }
+
+    public function rpc( $method, $input ): array
+    {
+        $this->out = $this->rclone->RcloneRPC( $method, $input );
+        $response = [
+            'output' => \FFI::string( $this->out->Output ),
+            'status' => $this->out->Status
+        ];
+        $this->rclone->RcloneFreeString( $this->out->Output );
+        return $response;
+    }
+
+    public function close( ): void
+    {
+        $this->rclone->RcloneFinalize();
+    }
+}