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Fixed DoWhile readloop on Windows, to fix some edge case reading race conditions

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This commit is contained in:
Bryan Roe
2019-10-29 10:58:41 -07:00
parent d92cf45e0e
commit 1be7ee3394
1 changed files with 21 additions and 9 deletions
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30
microstack/ILibProcessPipe.c
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@@ -1055,15 +1055,17 @@ void ILibProcessPipe_Process_ReadHandler(void* user)
do do
{ {
#ifdef WIN32 #ifdef WIN32
err = 0;
result = GetOverlappedResult(pipeObject->mPipe_ReadEnd, pipeObject->mOverlapped, &bytesRead, FALSE); result = GetOverlappedResult(pipeObject->mPipe_ReadEnd, pipeObject->mOverlapped, &bytesRead, FALSE);
if (result == FALSE) //printf("Overlapped(%p): %d bytes\n", pipeObject->mPipe_ReadEnd, bytesRead);
if (result == FALSE || bytesRead == 0)
{ {
err = GetLastError(); err = GetLastError();
break; break;
} }
#else #else
bytesRead = (int)read(pipeObject->mPipe_ReadEnd, pipeObject->buffer + pipeObject->readOffset + pipeObject->totalRead, pipeObject->bufferSize - pipeObject->totalRead); bytesRead = (int)read(pipeObject->mPipe_ReadEnd, pipeObject->buffer + pipeObject->readOffset + pipeObject->totalRead, pipeObject->bufferSize - pipeObject->totalRead);
if(bytesRead <= 0) if (bytesRead <= 0)
{ {
break; break;
} }
@@ -1081,7 +1083,7 @@ void ILibProcessPipe_Process_ReadHandler(void* user)
pipeObject->totalRead = 0; pipeObject->totalRead = 0;
continue; continue;
} }
while (pipeObject->PAUSED == 0) while (pipeObject->PAUSED == 0)
{ {
consumed = 0; consumed = 0;
@@ -1130,17 +1132,24 @@ void ILibProcessPipe_Process_ReadHandler(void* user)
pipeObject->bufferSize = pipeObject->bufferSize * 2; pipeObject->bufferSize = pipeObject->bufferSize * 2;
} }
if (pipeObject->PAUSED != 0) { break; } if (pipeObject->PAUSED == 0)
{
if (ReadFile(pipeObject->mPipe_ReadEnd, pipeObject->buffer + pipeObject->readOffset + pipeObject->totalRead, pipeObject->bufferSize - pipeObject->totalRead, NULL, pipeObject->mOverlapped) != TRUE)
{
break;
}
}
} }
#ifdef WIN32 #ifdef WIN32
while ((result = ReadFile(pipeObject->mPipe_ReadEnd, pipeObject->buffer + pipeObject->readOffset + pipeObject->totalRead, pipeObject->bufferSize - pipeObject->totalRead, NULL, pipeObject->mOverlapped)) == TRUE); // Note: This is actually the end of a do-while loop while (pipeObject->PAUSED == 0); // Note: This is actually the end of a do-while loop
if((err = GetLastError()) != ERROR_IO_PENDING && (pipeObject->PAUSED == 0 || pipeObject->totalRead == 0)) if(bytesRead == 0 || (err != ERROR_IO_PENDING && err != 0 && pipeObject->PAUSED == 0))
#else #else
while(pipeObject->PAUSED == 0); // Note: This is actually the end of a do-while loop while(pipeObject->PAUSED == 0); // Note: This is actually the end of a do-while loop
err = 0; err = 0;
if (bytesRead == 0 || ((err = errno) != EAGAIN && errno != EWOULDBLOCK && pipeObject->PAUSED == 0)) if (bytesRead == 0 || ((err = errno) != EAGAIN && errno != EWOULDBLOCK && pipeObject->PAUSED == 0))
#endif #endif
{ {
//printf("Broken Pipe(%p)? (err: %d, PAUSED: %d, totalRead: %d\n", pipeObject->mPipe_ReadEnd, err, pipeObject->PAUSED, pipeObject->totalRead);
// //
// Broken Pipe // Broken Pipe
// //
@@ -1318,7 +1327,7 @@ void ILibProcessPipe_Pipe_ResumeEx_ContinueProcessing(ILibProcessPipe_PipeObject
int consumed; int consumed;
p->PAUSED = 0; p->PAUSED = 0;
p->processingLoop = 1; p->processingLoop = 1;
while (p->readOffset != 0 && p->PAUSED == 0) while (p->PAUSED == 0 && p->totalRead > 0)
{ {
consumed = 0; consumed = 0;
((ILibProcessPipe_GenericReadHandler)p->handler)(p->buffer + p->readOffset, p->totalRead, &consumed, p->user1, p->user2); ((ILibProcessPipe_GenericReadHandler)p->handler)(p->buffer + p->readOffset, p->totalRead, &consumed, p->user1, p->user2);
@@ -1334,6 +1343,7 @@ void ILibProcessPipe_Pipe_ResumeEx_ContinueProcessing(ILibProcessPipe_PipeObject
// //
memmove_s(p->buffer, p->bufferSize, p->buffer + p->readOffset, p->totalRead); memmove_s(p->buffer, p->bufferSize, p->buffer + p->readOffset, p->totalRead);
p->readOffset = 0; p->readOffset = 0;
break;
} }
else if (consumed == p->totalRead) else if (consumed == p->totalRead)
{ {
@@ -1376,7 +1386,8 @@ void __stdcall ILibProcessPipe_Pipe_ResumeEx_APC(ULONG_PTR obj)
{ {
ILibProcessPipe_WaitHandle_Add(p->manager, p->mOverlapped->hEvent, p, ILibProcessPipe_Process_ReadHandler); ILibProcessPipe_WaitHandle_Add(p->manager, p->mOverlapped->hEvent, p, ILibProcessPipe_Process_ReadHandler);
} }
ReadFile(p->mPipe_ReadEnd, p->buffer, p->bufferSize, NULL, p->mOverlapped); //printf("ReadFile(%p, %d, %d) (ResumeEx_APC)\n", p->mPipe_ReadEnd, p->readOffset + p->totalRead, p->bufferSize - p->readOffset - p->totalRead);
ReadFile(p->mPipe_ReadEnd, p->buffer + p->readOffset + p->totalRead, p->bufferSize - p->readOffset - p->totalRead, NULL, p->mOverlapped);
} }
else else
{ {
@@ -1514,6 +1525,7 @@ void ILibProcessPipe_Process_StartPipeReader(ILibProcessPipe_PipeObject *pipeObj
if (pipeObject->mOverlapped != NULL) if (pipeObject->mOverlapped != NULL)
{ {
// This PIPE supports Overlapped I/O // This PIPE supports Overlapped I/O
//printf("ReadFile(%p, %d, %d) (StartPipeReader)\n", pipeObject->mPipe_ReadEnd, 0, pipeObject->bufferSize);
result = ReadFile(pipeObject->mPipe_ReadEnd, pipeObject->buffer, pipeObject->bufferSize, NULL, pipeObject->mOverlapped); result = ReadFile(pipeObject->mPipe_ReadEnd, pipeObject->buffer, pipeObject->bufferSize, NULL, pipeObject->mOverlapped);
ILibProcessPipe_WaitHandle_Add(pipeObject->manager, pipeObject->mOverlapped->hEvent, pipeObject, &ILibProcessPipe_Process_ReadHandler); ILibProcessPipe_WaitHandle_Add(pipeObject->manager, pipeObject->mOverlapped->hEvent, pipeObject, &ILibProcessPipe_Process_ReadHandler);
} }