pipe-win.cpp revision 42ee6d03355fb68926435ec4feb8e5293f391344
/* $Id$ */
/** @file
* IPRT - Anonymous Pipes, Windows Implementation.
*/
/*
* Copyright (C) 2010 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
* VirtualBox OSE distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#include <Windows.h>
#include <iprt/pipe.h>
#include "internal/iprt.h"
#include <iprt/asm.h>
#include <iprt/assert.h>
#include <iprt/critsect.h>
#include <iprt/err.h>
#include <iprt/mem.h>
#include <iprt/string.h>
#include <iprt/poll.h>
#include <iprt/process.h>
#include <iprt/thread.h>
#include <iprt/time.h>
#include "internal/pipe.h"
#include "internal/magics.h"
/*******************************************************************************
* Defined Constants And Macros *
*******************************************************************************/
/** The pipe buffer size we prefer. */
#define RTPIPE_NT_SIZE _64K
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
typedef struct RTPIPEINTERNAL
{
/** Magic value (RTPIPE_MAGIC). */
uint32_t u32Magic;
/** The pipe handle. */
HANDLE hPipe;
/** Set if this is the read end, clear if it's the write end. */
bool fRead;
/** Set if there is already pending I/O. */
bool fIOPending;
/** Set if the zero byte read that the poll code using is pending. */
bool fZeroByteRead;
/** Set if the pipe is broken. */
bool fBrokenPipe;
/** Set if we've promised that the handle is writable. */
bool fPromisedWritable;
/** Usage counter. */
uint32_t cUsers;
/** The overlapped I/O structure we use. */
OVERLAPPED Overlapped;
/** Bounce buffer for writes. */
uint8_t *pbBounceBuf;
/** Amount of used buffer space. */
size_t cbBounceBufUsed;
/** Amount of allocated buffer space. */
size_t cbBounceBufAlloc;
/** The handle of the poll set currently polling on this pipe.
* We can only have one poller at the time (lazy bird). */
RTPOLLSET hPollSet;
/** Critical section protecting the above members.
* (Taking the lazy/simple approach.) */
RTCRITSECT CritSect;
/** Buffer for the zero byte read. */
uint8_t abBuf[8];
} RTPIPEINTERNAL;
/* from ntdef.h */
typedef LONG NTSTATUS;
/* from ntddk.h */
typedef struct _IO_STATUS_BLOCK {
union {
NTSTATUS Status;
PVOID Pointer;
};
ULONG_PTR Information;
} IO_STATUS_BLOCK, *PIO_STATUS_BLOCK;
typedef enum _FILE_INFORMATION_CLASS {
FilePipeInformation = 23,
FilePipeLocalInformation = 24,
FilePipeRemoteInformation = 25,
} FILE_INFORMATION_CLASS, *PFILE_INFORMATION_CLASS;
/* from ntifs.h */
typedef struct _FILE_PIPE_LOCAL_INFORMATION {
ULONG NamedPipeType;
ULONG NamedPipeConfiguration;
ULONG MaximumInstances;
ULONG CurrentInstances;
ULONG InboundQuota;
ULONG ReadDataAvailable;
ULONG OutboundQuota;
ULONG WriteQuotaAvailable;
ULONG NamedPipeState;
ULONG NamedPipeEnd;
} FILE_PIPE_LOCAL_INFORMATION, *PFILE_PIPE_LOCAL_INFORMATION;
#define FILE_PIPE_DISCONNECTED_STATE 0x00000001
#define FILE_PIPE_LISTENING_STATE 0x00000002
#define FILE_PIPE_CONNECTED_STATE 0x00000003
#define FILE_PIPE_CLOSING_STATE 0x00000004
#define FILE_PIPE_INBOUND 0x00000000
#define FILE_PIPE_OUTBOUND 0x00000001
#define FILE_PIPE_FULL_DUPLEX 0x00000002
#define FILE_PIPE_CLIENT_END 0x00000000
#define FILE_PIPE_SERVER_END 0x00000001
extern "C" NTSYSAPI NTSTATUS WINAPI NtQueryInformationFile(HANDLE, PIO_STATUS_BLOCK, PVOID, LONG, FILE_INFORMATION_CLASS);
/**
* Wrapper for getting FILE_PIPE_LOCAL_INFORMATION via the NT API.
*
* @returns Success indicator (true/false).
* @param pThis The pipe.
* @param pInfo The info structure.
*/
static bool rtPipeQueryInfo(RTPIPEINTERNAL *pThis, FILE_PIPE_LOCAL_INFORMATION *pInfo)
{
IO_STATUS_BLOCK Ios;
RT_ZERO(Ios);
RT_ZERO(*pInfo);
NTSTATUS rcNt = NtQueryInformationFile(pThis->hPipe, &Ios, pInfo, sizeof(*pInfo), FilePipeLocalInformation);
return rcNt >= 0;
}
RTDECL(int) RTPipeCreate(PRTPIPE phPipeRead, PRTPIPE phPipeWrite, uint32_t fFlags)
{
AssertPtrReturn(phPipeRead, VERR_INVALID_POINTER);
AssertPtrReturn(phPipeWrite, VERR_INVALID_POINTER);
AssertReturn(!(fFlags & ~RTPIPE_C_VALID_MASK), VERR_INVALID_PARAMETER);
/*
* Create the read end of the pipe.
*/
DWORD dwErr;
HANDLE hPipeR;
HANDLE hPipeW;
int rc;
for (;;)
{
static volatile uint32_t g_iNextPipe = 0;
char szName[128];
RTStrPrintf(szName, sizeof(szName), "\\\\.\\pipe\\iprt-pipe-%u-%u", RTProcSelf(), ASMAtomicIncU32(&g_iNextPipe));
SECURITY_ATTRIBUTES SecurityAttributes;
PSECURITY_ATTRIBUTES pSecurityAttributes = NULL;
if (fFlags & RTPIPE_C_INHERIT_READ)
{
SecurityAttributes.nLength = sizeof(SecurityAttributes);
SecurityAttributes.lpSecurityDescriptor = NULL;
SecurityAttributes.bInheritHandle = TRUE;
pSecurityAttributes = &SecurityAttributes;
}
DWORD dwOpenMode = PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED;
#ifdef FILE_FLAG_FIRST_PIPE_INSTANCE
dwOpenMode |= FILE_FLAG_FIRST_PIPE_INSTANCE;
#endif
DWORD dwPipeMode = PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT;
#ifdef PIPE_REJECT_REMOTE_CLIENTS
dwPipeMode |= PIPE_REJECT_REMOTE_CLIENTS;
#endif
hPipeR = CreateNamedPipeA(szName, dwOpenMode, dwPipeMode, 1 /*nMaxInstances*/, RTPIPE_NT_SIZE, RTPIPE_NT_SIZE,
NMPWAIT_USE_DEFAULT_WAIT, pSecurityAttributes);
#ifdef PIPE_REJECT_REMOTE_CLIENTS
if (hPipeR == INVALID_HANDLE_VALUE && GetLastError() == ERROR_INVALID_PARAMETER)
{
dwPipeMode &= ~PIPE_REJECT_REMOTE_CLIENTS;
hPipeR = CreateNamedPipeA(szName, dwOpenMode, dwPipeMode, 1 /*nMaxInstances*/, RTPIPE_NT_SIZE, RTPIPE_NT_SIZE,
NMPWAIT_USE_DEFAULT_WAIT, pSecurityAttributes);
}
#endif
#ifdef FILE_FLAG_FIRST_PIPE_INSTANCE
if (hPipeR == INVALID_HANDLE_VALUE && GetLastError() == ERROR_INVALID_PARAMETER)
{
dwOpenMode &= ~FILE_FLAG_FIRST_PIPE_INSTANCE;
hPipeR = CreateNamedPipeA(szName, dwOpenMode, dwPipeMode, 1 /*nMaxInstances*/, RTPIPE_NT_SIZE, RTPIPE_NT_SIZE,
NMPWAIT_USE_DEFAULT_WAIT, pSecurityAttributes);
}
#endif
if (hPipeR != INVALID_HANDLE_VALUE)
{
/*
* Connect to the pipe (the write end).
* We add FILE_READ_ATTRIBUTES here to make sure we can query the
* pipe state later on.
*/
pSecurityAttributes = NULL;
if (fFlags & RTPIPE_C_INHERIT_WRITE)
{
SecurityAttributes.nLength = sizeof(SecurityAttributes);
SecurityAttributes.lpSecurityDescriptor = NULL;
SecurityAttributes.bInheritHandle = TRUE;
pSecurityAttributes = &SecurityAttributes;
}
hPipeW = CreateFileA(szName,
GENERIC_WRITE | FILE_READ_ATTRIBUTES /*dwDesiredAccess*/,
0 /*dwShareMode*/,
pSecurityAttributes,
OPEN_EXISTING /* dwCreationDisposition */,
FILE_FLAG_OVERLAPPED /*dwFlagsAndAttributes*/,
NULL /*hTemplateFile*/);
if (hPipeW != INVALID_HANDLE_VALUE)
break;
dwErr = GetLastError();
CloseHandle(hPipeR);
}
else
dwErr = GetLastError();
if ( dwErr != ERROR_PIPE_BUSY /* already exist - compatible */
&& dwErr != ERROR_ACCESS_DENIED /* already exist - incompatible */)
return RTErrConvertFromWin32(dwErr);
/* else: try again with a new name */
}
/*
* Create the two handles.
*/
RTPIPEINTERNAL *pThisR = (RTPIPEINTERNAL *)RTMemAllocZ(sizeof(RTPIPEINTERNAL));
if (pThisR)
{
RTPIPEINTERNAL *pThisW = (RTPIPEINTERNAL *)RTMemAllocZ(sizeof(RTPIPEINTERNAL));
if (pThisW)
{
rc = RTCritSectInit(&pThisR->CritSect);
if (RT_SUCCESS(rc))
{
rc = RTCritSectInit(&pThisW->CritSect);
if (RT_SUCCESS(rc))
{
pThisR->Overlapped.hEvent = CreateEvent(NULL, TRUE /*fManualReset*/,
TRUE /*fInitialState*/, NULL /*pName*/);
if (pThisR->Overlapped.hEvent != NULL)
{
pThisW->Overlapped.hEvent = CreateEvent(NULL, TRUE /*fManualReset*/,
TRUE /*fInitialState*/, NULL /*pName*/);
if (pThisW->Overlapped.hEvent != NULL)
{
pThisR->u32Magic = RTPIPE_MAGIC;
pThisW->u32Magic = RTPIPE_MAGIC;
pThisR->hPipe = hPipeR;
pThisW->hPipe = hPipeW;
pThisR->fRead = true;
pThisW->fRead = false;
//pThisR->fIOPending = false;
//pThisW->fIOPending = false;
//pThisR->fZeroByteRead = false;
//pThisW->fZeroByteRead = false;
//pThisR->fBrokenPipe = false;
//pThisW->fBrokenPipe = false;
//pThisW->fPromisedWritable= false;
//pThisR->fPromisedWritable= false;
//pThisR->cUsers = 0;
//pThisW->cUsers = 0;
//pThisR->pbBounceBuf = NULL;
//pThisW->pbBounceBuf = NULL;
//pThisR->cbBounceBufUsed = 0;
//pThisW->cbBounceBufUsed = 0;
//pThisR->cbBounceBufAlloc= 0;
//pThisW->cbBounceBufAlloc= 0;
pThisR->hPollSet = NIL_RTPOLLSET;
pThisW->hPollSet = NIL_RTPOLLSET;
*phPipeRead = pThisR;
*phPipeWrite = pThisW;
return VINF_SUCCESS;
}
CloseHandle(pThisR->Overlapped.hEvent);
}
RTCritSectDelete(&pThisW->CritSect);
}
RTCritSectDelete(&pThisR->CritSect);
}
RTMemFree(pThisW);
}
else
rc = VERR_NO_MEMORY;
RTMemFree(pThisR);
}
else
rc = VERR_NO_MEMORY;
CloseHandle(hPipeR);
CloseHandle(hPipeW);
return rc;
}
/**
* Common worker for handling I/O completion.
*
* This is used by RTPipeClose, RTPipeWrite and RTPipeWriteBlocking.
*
* @returns IPRT status code.
* @param pThis The pipe instance handle.
*/
static int rtPipeWriteCheckCompletion(RTPIPEINTERNAL *pThis)
{
int rc;
DWORD dwRc = WaitForSingleObject(pThis->Overlapped.hEvent, 0);
if (dwRc == WAIT_OBJECT_0)
{
DWORD cbWritten = 0;
if (GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbWritten, TRUE))
{
for (;;)
{
if (cbWritten >= pThis->cbBounceBufUsed)
{
pThis->fIOPending = false;
rc = VINF_SUCCESS;
break;
}
/* resubmit the remainder of the buffer - can this actually happen? */
memmove(&pThis->pbBounceBuf[0], &pThis->pbBounceBuf[cbWritten], pThis->cbBounceBufUsed - cbWritten);
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
if (!WriteFile(pThis->hPipe, pThis->pbBounceBuf, (DWORD)pThis->cbBounceBufUsed,
&cbWritten, &pThis->Overlapped))
{
if (GetLastError() == ERROR_IO_PENDING)
rc = VINF_TRY_AGAIN;
else
{
pThis->fIOPending = false;
if (GetLastError() == ERROR_NO_DATA)
rc = VERR_BROKEN_PIPE;
else
rc = RTErrConvertFromWin32(GetLastError());
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
}
break;
}
Assert(cbWritten > 0);
}
}
else
{
pThis->fIOPending = false;
rc = RTErrConvertFromWin32(GetLastError());
}
}
else if (dwRc == WAIT_TIMEOUT)
rc = VINF_TRY_AGAIN;
else
{
pThis->fIOPending = false;
if (dwRc == WAIT_ABANDONED)
rc = VERR_INVALID_HANDLE;
else
rc = RTErrConvertFromWin32(GetLastError());
}
return rc;
}
RTDECL(int) RTPipeClose(RTPIPE hPipe)
{
RTPIPEINTERNAL *pThis = hPipe;
if (pThis == NIL_RTPIPE)
return VINF_SUCCESS;
AssertPtrReturn(pThis, VERR_INVALID_PARAMETER);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
/*
* Do the cleanup.
*/
AssertReturn(ASMAtomicCmpXchgU32(&pThis->u32Magic, ~RTPIPE_MAGIC, RTPIPE_MAGIC), VERR_INVALID_HANDLE);
RTCritSectEnter(&pThis->CritSect);
Assert(pThis->cUsers == 0);
if (!pThis->fRead && pThis->fIOPending)
rtPipeWriteCheckCompletion(pThis);
CloseHandle(pThis->hPipe);
pThis->hPipe = INVALID_HANDLE_VALUE;
CloseHandle(pThis->Overlapped.hEvent);
pThis->Overlapped.hEvent = NULL;
RTMemFree(pThis->pbBounceBuf);
pThis->pbBounceBuf = NULL;
RTCritSectLeave(&pThis->CritSect);
RTCritSectDelete(&pThis->CritSect);
RTMemFree(pThis);
return VINF_SUCCESS;
}
RTDECL(int) RTPipeFromNative(PRTPIPE phPipe, RTHCINTPTR hNativePipe, uint32_t fFlags)
{
AssertPtrReturn(phPipe, VERR_INVALID_POINTER);
AssertReturn(!(fFlags & ~RTPIPE_N_VALID_MASK), VERR_INVALID_PARAMETER);
AssertReturn(!!(fFlags & RTPIPE_N_READ) != !!(fFlags & RTPIPE_N_WRITE), VERR_INVALID_PARAMETER);
/*
* Get and validate the pipe handle info.
*/
HANDLE hNative = (HANDLE)hNativePipe;
AssertReturn(GetFileType(hNative) == FILE_TYPE_PIPE, VERR_INVALID_HANDLE);
DWORD cMaxInstances;
DWORD fInfo;
if (!GetNamedPipeInfo(hNative, &fInfo, NULL, NULL, &cMaxInstances))
return RTErrConvertFromWin32(GetLastError());
AssertReturn(!(fInfo & PIPE_TYPE_MESSAGE), VERR_INVALID_HANDLE);
AssertReturn(cMaxInstances == 1, VERR_INVALID_HANDLE);
DWORD cInstances;
DWORD fState;
if (!GetNamedPipeHandleState(hNative, &fState, &cInstances, NULL, NULL, NULL, 0))
return RTErrConvertFromWin32(GetLastError());
AssertReturn(!(fState & PIPE_NOWAIT), VERR_INVALID_HANDLE);
AssertReturn(!(fState & PIPE_READMODE_MESSAGE), VERR_INVALID_HANDLE);
AssertReturn(cInstances <= 1, VERR_INVALID_HANDLE);
/*
* Looks kind of OK, create a handle so we can try rtPipeQueryInfo on it
* and see if we need to duplicate it to make that call work.
*/
RTPIPEINTERNAL *pThis = (RTPIPEINTERNAL *)RTMemAllocZ(sizeof(RTPIPEINTERNAL));
if (!pThis)
return VERR_NO_MEMORY;
int rc = RTCritSectInit(&pThis->CritSect);
if (RT_SUCCESS(rc))
{
pThis->Overlapped.hEvent = CreateEvent(NULL, TRUE /*fManualReset*/,
TRUE /*fInitialState*/, NULL /*pName*/);
if (pThis->Overlapped.hEvent != NULL)
{
pThis->u32Magic = RTPIPE_MAGIC;
pThis->hPipe = hNative;
pThis->fRead = !!(fFlags & RTPIPE_N_READ);
//pThis->fIOPending = false;
//pThis->fZeroByteRead = false;
//pThis->fBrokenPipe = false;
//pThisR->fPromisedWritable= false;
//pThis->cUsers = 0;
//pThis->pbBounceBuf = NULL;
//pThis->cbBounceBufUsed = 0;
//pThis->cbBounceBufAlloc= 0;
pThis->hPollSet = NIL_RTPOLLSET;
HANDLE hNative2 = INVALID_HANDLE_VALUE;
FILE_PIPE_LOCAL_INFORMATION Info;
if (rtPipeQueryInfo(pThis, &Info))
rc = VINF_SUCCESS;
else
{
if (DuplicateHandle(GetCurrentProcess() /*hSrcProcess*/, hNative /*hSrcHandle*/,
GetCurrentProcess() /*hDstProcess*/, &hNative2 /*phDstHandle*/,
pThis->fRead ? GENERIC_READ : GENERIC_WRITE | FILE_READ_ATTRIBUTES /*dwDesiredAccess*/,
!!(fFlags & RTPIPE_N_INHERIT) /*fInheritHandle*/,
0 /*dwOptions*/))
{
pThis->hPipe = hNative2;
if (rtPipeQueryInfo(pThis, &Info))
rc = VINF_SUCCESS;
else
{
rc = VERR_ACCESS_DENIED;
CloseHandle(hNative2);
}
}
else
hNative2 = INVALID_HANDLE_VALUE;
}
if (RT_SUCCESS(rc))
{
/*
* Verify the pipe state and correct the inheritability.
*/
AssertStmt( Info.NamedPipeState == FILE_PIPE_CONNECTED_STATE
|| Info.NamedPipeState == FILE_PIPE_CLOSING_STATE
|| Info.NamedPipeState == FILE_PIPE_DISCONNECTED_STATE,
VERR_INVALID_HANDLE);
AssertStmt( Info.NamedPipeConfiguration
== ( Info.NamedPipeEnd == FILE_PIPE_SERVER_END
? (pThis->fRead ? FILE_PIPE_INBOUND : FILE_PIPE_OUTBOUND)
: (pThis->fRead ? FILE_PIPE_OUTBOUND : FILE_PIPE_INBOUND) ),
VERR_INVALID_HANDLE);
if ( RT_SUCCESS(rc)
&& hNative2 == INVALID_HANDLE_VALUE
&& !SetHandleInformation(hNative,
HANDLE_FLAG_INHERIT /*dwMask*/,
fFlags & RTPIPE_N_INHERIT ? HANDLE_FLAG_INHERIT : 0))
{
rc = RTErrConvertFromWin32(GetLastError());
AssertMsgFailed(("%Rrc\n", rc));
}
if (RT_SUCCESS(rc))
{
/*
* Ok, we're good!
*/
if (hNative2 != INVALID_HANDLE_VALUE)
CloseHandle(hNative);
*phPipe = pThis;
return VINF_SUCCESS;
}
}
/* Bail out. */
if (hNative2 != INVALID_HANDLE_VALUE)
CloseHandle(hNative2);
CloseHandle(pThis->Overlapped.hEvent);
}
RTCritSectDelete(&pThis->CritSect);
}
RTMemFree(pThis);
return rc;
}
RTDECL(RTHCINTPTR) RTPipeToNative(RTPIPE hPipe)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, -1);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, -1);
return (RTHCINTPTR)pThis->hPipe;
}
RTDECL(int) RTPipeRead(RTPIPE hPipe, void *pvBuf, size_t cbToRead, size_t *pcbRead)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(pThis->fRead, VERR_ACCESS_DENIED);
AssertPtr(pcbRead);
AssertPtr(pvBuf);
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_SUCCESS(rc))
{
/* No concurrent readers, sorry. */
if (pThis->cUsers == 0)
{
pThis->cUsers++;
/*
* Kick of a an overlapped read. It should return immediately if
* there is bytes in the buffer. If not, we'll cancel it and see
* what we get back.
*/
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
DWORD cbRead = 0;
if ( cbToRead == 0
|| ReadFile(pThis->hPipe, pvBuf,
cbToRead <= ~(DWORD)0 ? (DWORD)cbToRead : ~(DWORD)0,
&cbRead, &pThis->Overlapped))
{
*pcbRead = cbRead;
rc = VINF_SUCCESS;
}
else if (GetLastError() == ERROR_IO_PENDING)
{
pThis->fIOPending = true;
RTCritSectLeave(&pThis->CritSect);
if (!CancelIo(pThis->hPipe))
WaitForSingleObject(pThis->Overlapped.hEvent, INFINITE);
if (GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbRead, TRUE /*fWait*/))
{
*pcbRead = cbRead;
rc = VINF_SUCCESS;
}
else if (GetLastError() == ERROR_OPERATION_ABORTED)
{
*pcbRead = 0;
rc = VINF_TRY_AGAIN;
}
else
rc = RTErrConvertFromWin32(GetLastError());
RTCritSectEnter(&pThis->CritSect);
pThis->fIOPending = false;
}
else
rc = RTErrConvertFromWin32(GetLastError());
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
pThis->cUsers--;
}
else
rc = VERR_WRONG_ORDER;
RTCritSectLeave(&pThis->CritSect);
}
return rc;
}
RTDECL(int) RTPipeReadBlocking(RTPIPE hPipe, void *pvBuf, size_t cbToRead, size_t *pcbRead)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(pThis->fRead, VERR_ACCESS_DENIED);
AssertPtr(pvBuf);
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_SUCCESS(rc))
{
/* No concurrent readers, sorry. */
if (pThis->cUsers == 0)
{
pThis->cUsers++;
size_t cbTotalRead = 0;
while (cbToRead > 0)
{
/*
* Kick of a an overlapped read. It should return immediately if
* there is bytes in the buffer. If not, we'll cancel it and see
* what we get back.
*/
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
DWORD cbRead = 0;
pThis->fIOPending = true;
RTCritSectLeave(&pThis->CritSect);
if (ReadFile(pThis->hPipe, pvBuf,
cbToRead <= ~(DWORD)0 ? (DWORD)cbToRead : ~(DWORD)0,
&cbRead, &pThis->Overlapped))
rc = VINF_SUCCESS;
else if (GetLastError() == ERROR_IO_PENDING)
{
WaitForSingleObject(pThis->Overlapped.hEvent, INFINITE);
if (GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbRead, TRUE /*fWait*/))
rc = VINF_SUCCESS;
else
rc = RTErrConvertFromWin32(GetLastError());
}
else
rc = RTErrConvertFromWin32(GetLastError());
RTCritSectEnter(&pThis->CritSect);
pThis->fIOPending = false;
if (RT_FAILURE(rc))
break;
/* advance */
cbToRead -= cbRead;
cbTotalRead += cbRead;
pvBuf = (uint8_t *)pvBuf + cbRead;
}
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
if (pcbRead)
{
*pcbRead = cbTotalRead;
if ( RT_FAILURE(rc)
&& cbTotalRead
&& rc != VERR_INVALID_POINTER)
rc = VINF_SUCCESS;
}
pThis->cUsers--;
}
else
rc = VERR_WRONG_ORDER;
RTCritSectLeave(&pThis->CritSect);
}
return rc;
}
RTDECL(int) RTPipeWrite(RTPIPE hPipe, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(!pThis->fRead, VERR_ACCESS_DENIED);
AssertPtr(pcbWritten);
AssertPtr(pvBuf);
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_SUCCESS(rc))
{
/* No concurrent readers, sorry. */
if (pThis->cUsers == 0)
{
pThis->cUsers++;
/* If I/O is pending, check if it has completed. */
if (pThis->fIOPending)
rc = rtPipeWriteCheckCompletion(pThis);
else
rc = VINF_SUCCESS;
if (rc == VINF_SUCCESS)
{
Assert(!pThis->fIOPending);
/* Adjust the number of bytes to write to fit into the current
buffer quota, unless we've promised stuff in RTPipeSelectOne.
WriteQuotaAvailable better not be zero when it shouldn't!! */
FILE_PIPE_LOCAL_INFORMATION Info;
if ( !pThis->fPromisedWritable
&& cbToWrite > 0
&& rtPipeQueryInfo(pThis, &Info))
{
if (Info.NamedPipeState == FILE_PIPE_CLOSING_STATE)
rc = VERR_BROKEN_PIPE;
/** @todo fixme: To get the pipe writing support to work the
* block below needs to be commented out until a
* way is found to address the problem of the incorrectly
* set field Info.WriteQuotaAvailable. */
#if 0
else if ( cbToWrite >= Info.WriteQuotaAvailable
&& Info.OutboundQuota != 0
&& (Info.WriteQuotaAvailable || pThis->cbBounceBufAlloc)
)
{
cbToWrite = Info.WriteQuotaAvailable;
if (!cbToWrite)
rc = VINF_TRY_AGAIN;
}
#endif
}
pThis->fPromisedWritable = false;
/* Do the bounce buffering. */
if ( pThis->cbBounceBufAlloc < cbToWrite
&& pThis->cbBounceBufAlloc < RTPIPE_NT_SIZE)
{
if (cbToWrite > RTPIPE_NT_SIZE)
cbToWrite = RTPIPE_NT_SIZE;
void *pv = RTMemRealloc(pThis->pbBounceBuf, RT_ALIGN_Z(cbToWrite, _1K));
if (pv)
{
pThis->pbBounceBuf = (uint8_t *)pv;
pThis->cbBounceBufAlloc = RT_ALIGN_Z(cbToWrite, _1K);
}
else
rc = VERR_NO_MEMORY;
}
else if (cbToWrite > RTPIPE_NT_SIZE)
cbToWrite = RTPIPE_NT_SIZE;
if (RT_SUCCESS(rc) && cbToWrite)
{
memcpy(pThis->pbBounceBuf, pvBuf, cbToWrite);
pThis->cbBounceBufUsed = (uint32_t)cbToWrite;
/* Submit the write. */
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
DWORD cbWritten = 0;
if (WriteFile(pThis->hPipe, pThis->pbBounceBuf, (DWORD)pThis->cbBounceBufUsed,
&cbWritten, &pThis->Overlapped))
{
*pcbWritten = cbWritten;
rc = VINF_SUCCESS;
}
else if (GetLastError() == ERROR_IO_PENDING)
{
*pcbWritten = cbToWrite;
pThis->fIOPending = true;
rc = VINF_SUCCESS;
}
else if (GetLastError() == ERROR_NO_DATA)
rc = VERR_BROKEN_PIPE;
else
rc = RTErrConvertFromWin32(GetLastError());
}
else if (RT_SUCCESS(rc))
*pcbWritten = 0;
}
else if (RT_SUCCESS(rc))
*pcbWritten = 0;
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
pThis->cUsers--;
}
else
rc = VERR_WRONG_ORDER;
RTCritSectLeave(&pThis->CritSect);
}
return rc;
}
RTDECL(int) RTPipeWriteBlocking(RTPIPE hPipe, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(!pThis->fRead, VERR_ACCESS_DENIED);
AssertPtr(pvBuf);
AssertPtrNull(pcbWritten);
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_SUCCESS(rc))
{
/* No concurrent readers, sorry. */
if (pThis->cUsers == 0)
{
pThis->cUsers++;
/*
* If I/O is pending, wait for it to complete.
*/
if (pThis->fIOPending)
{
rc = rtPipeWriteCheckCompletion(pThis);
while (rc == VINF_TRY_AGAIN)
{
Assert(pThis->fIOPending);
HANDLE hEvent = pThis->Overlapped.hEvent;
RTCritSectLeave(&pThis->CritSect);
WaitForSingleObject(pThis->Overlapped.hEvent, INFINITE);
RTCritSectEnter(&pThis->CritSect);
}
}
if (RT_SUCCESS(rc))
{
Assert(!pThis->fIOPending);
pThis->fPromisedWritable = false;
/*
* Try write everything.
* No bounce buffering, cUsers protects us.
*/
size_t cbTotalWritten = 0;
while (cbToWrite > 0)
{
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
pThis->fIOPending = true;
RTCritSectLeave(&pThis->CritSect);
DWORD cbWritten = 0;
if (WriteFile(pThis->hPipe, pvBuf,
cbToWrite <= ~(DWORD)0 ? (DWORD)cbToWrite : ~(DWORD)0,
&cbWritten, &pThis->Overlapped))
rc = VINF_SUCCESS;
else if (GetLastError() == ERROR_IO_PENDING)
{
WaitForSingleObject(pThis->Overlapped.hEvent, INFINITE);
if (GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbWritten, TRUE /*fWait*/))
rc = VINF_SUCCESS;
else
rc = RTErrConvertFromWin32(GetLastError());
}
else if (GetLastError() == ERROR_NO_DATA)
rc = VERR_BROKEN_PIPE;
else
rc = RTErrConvertFromWin32(GetLastError());
RTCritSectEnter(&pThis->CritSect);
pThis->fIOPending = false;
if (RT_FAILURE(rc))
break;
/* advance */
pvBuf = (char const *)pvBuf + cbWritten;
cbTotalWritten += cbWritten;
cbToWrite -= cbWritten;
}
if (pcbWritten)
{
*pcbWritten = cbTotalWritten;
if ( RT_FAILURE(rc)
&& cbTotalWritten
&& rc != VERR_INVALID_POINTER)
rc = VINF_SUCCESS;
}
}
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
pThis->cUsers--;
}
else
rc = VERR_WRONG_ORDER;
RTCritSectLeave(&pThis->CritSect);
}
return rc;
#if 1
return VERR_NOT_IMPLEMENTED;
#else
int rc = rtPipeTryBlocking(pThis);
if (RT_SUCCESS(rc))
{
size_t cbTotalWritten = 0;
while (cbToWrite > 0)
{
ssize_t cbWritten = write(pThis->fd, pvBuf, RT_MIN(cbToWrite, SSIZE_MAX));
if (cbWritten < 0)
{
rc = RTErrConvertFromErrno(errno);
break;
}
/* advance */
pvBuf = (char const *)pvBuf + cbWritten;
cbTotalWritten += cbWritten;
cbToWrite -= cbWritten;
}
if (pcbWritten)
{
*pcbWritten = cbTotalWritten;
if ( RT_FAILURE(rc)
&& cbTotalWritten
&& rc != VERR_INVALID_POINTER)
rc = VINF_SUCCESS;
}
ASMAtomicDecU32(&pThis->u32State);
}
return rc;
#endif
}
RTDECL(int) RTPipeFlush(RTPIPE hPipe)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(!pThis->fRead, VERR_ACCESS_DENIED);
if (!FlushFileBuffers(pThis->hPipe))
{
int rc = RTErrConvertFromWin32(GetLastError());
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
return rc;
}
return VINF_SUCCESS;
}
RTDECL(int) RTPipeSelectOne(RTPIPE hPipe, RTMSINTERVAL cMillies)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
uint64_t const StartMsTS = RTTimeMilliTS();
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_FAILURE(rc))
return rc;
for (unsigned iLoop = 0;; iLoop++)
{
HANDLE hWait = INVALID_HANDLE_VALUE;
if (pThis->fRead)
{
if (pThis->fIOPending)
hWait = pThis->Overlapped.hEvent;
else
{
/* Peek at the pipe buffer and see how many bytes it contains. */
DWORD cbAvailable;
if ( PeekNamedPipe(pThis->hPipe, NULL, 0, NULL, &cbAvailable, NULL)
&& cbAvailable > 0)
{
rc = VINF_SUCCESS;
break;
}
/* Start a zero byte read operation that we can wait on. */
if (cMillies == 0)
{
rc = VERR_TIMEOUT;
break;
}
AssertBreakStmt(pThis->cUsers == 0, rc = VERR_INTERNAL_ERROR_5);
rc = ResetEvent(pThis->Overlapped.hEvent); Assert(rc == TRUE);
DWORD cbRead = 0;
if (ReadFile(pThis->hPipe, pThis->abBuf, 0, &cbRead, &pThis->Overlapped))
{
rc = VINF_SUCCESS;
if (iLoop > 10)
RTThreadYield();
}
else if (GetLastError() == ERROR_IO_PENDING)
{
pThis->cUsers++;
pThis->fIOPending = true;
pThis->fZeroByteRead = true;
hWait = pThis->Overlapped.hEvent;
}
else
rc = RTErrConvertFromWin32(GetLastError());
}
}
else
{
if (pThis->fIOPending)
{
rc = rtPipeWriteCheckCompletion(pThis);
if (RT_FAILURE(rc))
break;
}
if (pThis->fIOPending)
hWait = pThis->Overlapped.hEvent;
else
{
FILE_PIPE_LOCAL_INFORMATION Info;
if (rtPipeQueryInfo(pThis, &Info))
{
/* Check for broken pipe. */
if (Info.NamedPipeState == FILE_PIPE_CLOSING_STATE)
{
rc = VERR_BROKEN_PIPE;
break;
}
/* Check for available write buffer space. */
else if (Info.WriteQuotaAvailable > 0)
{
pThis->fPromisedWritable = false;
rc = VINF_SUCCESS;
break;
}
/* delayed buffer alloc or timeout: phony promise
later: See if we still can associate a semaphore with
the pipe, like on OS/2. */
else if ( Info.OutboundQuota == 0
|| cMillies)
{
pThis->fPromisedWritable = true;
rc = VINF_SUCCESS;
break;
}
}
else
{
pThis->fPromisedWritable = true;
rc = VINF_SUCCESS;
break;
}
}
}
if (RT_FAILURE(rc))
break;
/*
* Check for timeout.
*/
DWORD cMsMaxWait = INFINITE;
if ( cMillies != RT_INDEFINITE_WAIT
&& ( hWait != INVALID_HANDLE_VALUE
|| iLoop > 10)
)
{
uint64_t cElapsed = RTTimeMilliTS() - StartMsTS;
if (cElapsed >= cMillies)
{
rc = VERR_TIMEOUT;
break;
}
cMsMaxWait = cMillies - (uint32_t)cElapsed;
}
/*
* Wait.
*/
if (hWait != INVALID_HANDLE_VALUE)
{
RTCritSectLeave(&pThis->CritSect);
DWORD dwRc = WaitForSingleObject(hWait, cMsMaxWait);
if (dwRc == WAIT_OBJECT_0)
rc = VINF_SUCCESS;
else if (dwRc == WAIT_TIMEOUT)
rc = VERR_TIMEOUT;
else if (dwRc == WAIT_ABANDONED)
rc = VERR_INVALID_HANDLE;
else
rc = RTErrConvertFromWin32(GetLastError());
if ( RT_FAILURE(rc)
&& pThis->u32Magic != RTPIPE_MAGIC)
return rc;
RTCritSectEnter(&pThis->CritSect);
if (pThis->fZeroByteRead)
{
pThis->cUsers--;
pThis->fIOPending = false;
if (rc != VINF_SUCCESS)
CancelIo(pThis->hPipe);
DWORD cbRead = 0;
GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbRead, TRUE /*fWait*/);
}
if (RT_FAILURE(rc))
break;
}
}
if (rc == VERR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
RTCritSectLeave(&pThis->CritSect);
return rc;
}
RTDECL(int) RTPipeQueryReadable(RTPIPE hPipe, size_t *pcbReadable)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(pThis->fRead, VERR_PIPE_NOT_READ);
AssertPtrReturn(pcbReadable, VERR_INVALID_POINTER);
int rc = RTCritSectEnter(&pThis->CritSect);
if (RT_FAILURE(rc))
return rc;
DWORD cbAvailable = 0;
if (PeekNamedPipe(pThis->hPipe, NULL, 0, NULL, &cbAvailable, NULL))
*pcbReadable = cbAvailable;
else
rc = RTErrConvertFromWin32(GetLastError());
RTCritSectLeave(&pThis->CritSect);
return rc;
}
/**
* Internal RTPollSetAdd helper that returns the handle that should be added to
* the pollset.
*
* @returns Valid handle on success, INVALID_HANDLE_VALUE on failure.
* @param hPipe The pipe handle.
* @param fEvents The events we're polling for.
* @param ph where to put the primary handle.
*/
int rtPipePollGetHandle(RTPIPE hPipe, uint32_t fEvents, PHANDLE ph)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, VERR_INVALID_HANDLE);
AssertReturn(!(fEvents & RTPOLL_EVT_READ) || pThis->fRead, VERR_INVALID_PARAMETER);
AssertReturn(!(fEvents & RTPOLL_EVT_WRITE) || !pThis->fRead, VERR_INVALID_PARAMETER);
/* Later: Try register an event handle with the pipe like on OS/2, there is
a file control for doing this obviously intended for the OS/2 subsys.
The question is whether this still exists on Vista and W7. */
*ph = pThis->Overlapped.hEvent;
return VINF_SUCCESS;
}
/**
* Checks for pending events.
*
* @returns Event mask or 0.
* @param pThis The pipe handle.
* @param fEvents The desired events.
*/
static uint32_t rtPipePollCheck(RTPIPEINTERNAL *pThis, uint32_t fEvents)
{
uint32_t fRetEvents = 0;
if (pThis->fBrokenPipe)
fRetEvents |= RTPOLL_EVT_ERROR;
else if (pThis->fRead)
{
if (!pThis->fIOPending)
{
DWORD cbAvailable;
if (PeekNamedPipe(pThis->hPipe, NULL, 0, NULL, &cbAvailable, NULL))
{
if ( (fEvents & RTPOLL_EVT_READ)
&& cbAvailable > 0)
fRetEvents |= RTPOLL_EVT_READ;
}
else
{
if (GetLastError() == ERROR_BROKEN_PIPE)
pThis->fBrokenPipe = true;
fRetEvents |= RTPOLL_EVT_ERROR;
}
}
}
else
{
if (pThis->fIOPending)
{
rtPipeWriteCheckCompletion(pThis);
if (pThis->fBrokenPipe)
fRetEvents |= RTPOLL_EVT_ERROR;
}
if ( !pThis->fIOPending
&& !fRetEvents)
{
FILE_PIPE_LOCAL_INFORMATION Info;
if (rtPipeQueryInfo(pThis, &Info))
{
/* Check for broken pipe. */
if (Info.NamedPipeState == FILE_PIPE_CLOSING_STATE)
{
fRetEvents = RTPOLL_EVT_ERROR;
pThis->fBrokenPipe = true;
}
/* Check if there is available buffer space. */
if ( !fRetEvents
&& (fEvents & RTPOLL_EVT_WRITE)
&& ( Info.WriteQuotaAvailable > 0
|| Info.OutboundQuota == 0)
)
fRetEvents |= RTPOLL_EVT_WRITE;
}
else if (fEvents & RTPOLL_EVT_WRITE)
fRetEvents |= RTPOLL_EVT_WRITE;
}
}
return fRetEvents;
}
/**
* Internal RTPoll helper that polls the pipe handle and, if @a fNoWait is
* clear, starts whatever actions we've got running during the poll call.
*
* @returns 0 if no pending events, actions initiated if @a fNoWait is clear.
* Event mask (in @a fEvents) and no actions if the handle is ready
* already.
* UINT32_MAX (asserted) if the pipe handle is busy in I/O or a
* different poll set.
*
* @param hPipe The pipe handle.
* @param hPollSet The poll set handle (for access checks).
* @param fEvents The events we're polling for.
* @param fFinalEntry Set if this is the final entry for this handle
* in this poll set. This can be used for dealing
* with duplicate entries.
* @param fNoWait Set if it's a zero-wait poll call. Clear if
* we'll wait for an event to occur.
*/
uint32_t rtPipePollStart(RTPIPE hPipe, RTPOLLSET hPollSet, uint32_t fEvents, bool fFinalEntry, bool fNoWait)
{
/** @todo All this polling code could be optimized to make fewer system
* calls; like for instance the ResetEvent calls. */
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, UINT32_MAX);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, UINT32_MAX);
int rc = RTCritSectEnter(&pThis->CritSect);
AssertRCReturn(rc, UINT32_MAX);
/* Check that this is the only current use of this pipe. */
uint32_t fRetEvents;
if ( pThis->cUsers == 0
|| pThis->hPollSet == hPollSet)
{
/* Check what the current events are. */
fRetEvents = rtPipePollCheck(pThis, fEvents);
if ( !fRetEvents
&& !fNoWait)
{
/* Make sure the event semaphore has been reset. */
if (!pThis->fIOPending)
{
rc = ResetEvent(pThis->Overlapped.hEvent);
Assert(rc == TRUE);
}
/* Kick off the zero byte read thing if applicable. */
if ( !pThis->fIOPending
&& pThis->fRead
&& (fEvents & RTPOLL_EVT_READ)
)
{
DWORD cbRead = 0;
if (ReadFile(pThis->hPipe, pThis->abBuf, 0, &cbRead, &pThis->Overlapped))
fRetEvents = rtPipePollCheck(pThis, fEvents);
else if (GetLastError() == ERROR_IO_PENDING)
{
pThis->fIOPending = true;
pThis->fZeroByteRead = true;
}
else
fRetEvents = RTPOLL_EVT_ERROR;
}
/* If we're still set for the waiting, record the poll set and
mark the pipe used. */
if (!fRetEvents)
{
pThis->cUsers++;
pThis->hPollSet = hPollSet;
}
}
}
else
{
AssertFailed();
fRetEvents = UINT32_MAX;
}
RTCritSectLeave(&pThis->CritSect);
return fRetEvents;
}
/**
* Called after a WaitForMultipleObjects returned in order to check for pending
* events and stop whatever actions that rtPipePollStart() initiated.
*
* @returns Event mask or 0.
*
* @param hPipe The pipe handle.
* @param fEvents The events we're polling for.
* @param fFinalEntry Set if this is the final entry for this handle
* in this poll set. This can be used for dealing
* with duplicate entries. Only keep in mind that
* this method is called in reverse order, so the
* first call will have this set (when the entire
* set was processed).
* @param fHarvestEvents Set if we should check for pending events.
*/
uint32_t rtPipePollDone(RTPIPE hPipe, uint32_t fEvents, bool fFinalEntry, bool fHarvestEvents)
{
RTPIPEINTERNAL *pThis = hPipe;
AssertPtrReturn(pThis, 0);
AssertReturn(pThis->u32Magic == RTPIPE_MAGIC, 0);
int rc = RTCritSectEnter(&pThis->CritSect);
AssertRCReturn(rc, 0);
Assert(pThis->cUsers > 0);
/* Cancel the zero byte read. */
uint32_t fRetEvents = 0;
if (pThis->fZeroByteRead)
{
CancelIo(pThis->hPipe);
DWORD cbRead = 0;
if ( !GetOverlappedResult(pThis->hPipe, &pThis->Overlapped, &cbRead, TRUE /*fWait*/)
&& GetLastError() != ERROR_OPERATION_ABORTED)
fRetEvents = RTPOLL_EVT_ERROR;
pThis->fIOPending = false;
pThis->fZeroByteRead = false;
}
/* harvest events. */
fRetEvents |= rtPipePollCheck(pThis, fEvents);
/* update counters. */
pThis->cUsers--;
if (!pThis->cUsers)
pThis->hPollSet = NIL_RTPOLLSET;
RTCritSectLeave(&pThis->CritSect);
return fRetEvents;
}