diff options
Diffstat (limited to 'src/corelib/io/qwindowspipereader.cpp')
| -rw-r--r-- | src/corelib/io/qwindowspipereader.cpp | 154 |
1 files changed, 98 insertions, 56 deletions
diff --git a/src/corelib/io/qwindowspipereader.cpp b/src/corelib/io/qwindowspipereader.cpp index 95232385b2..15fb276be9 100644 --- a/src/corelib/io/qwindowspipereader.cpp +++ b/src/corelib/io/qwindowspipereader.cpp @@ -38,28 +38,40 @@ ****************************************************************************/ #include "qwindowspipereader_p.h" -#include "qwinoverlappedionotifier_p.h" -#include <qdebug.h> +#include "qiodevice_p.h" #include <qelapsedtimer.h> -#include <qeventloop.h> QT_BEGIN_NAMESPACE +QWindowsPipeReader::Overlapped::Overlapped(QWindowsPipeReader *reader) + : pipeReader(reader) +{ +} + +void QWindowsPipeReader::Overlapped::clear() +{ + ZeroMemory(this, sizeof(OVERLAPPED)); +} + + QWindowsPipeReader::QWindowsPipeReader(QObject *parent) : QObject(parent), handle(INVALID_HANDLE_VALUE), + overlapped(this), readBufferMaxSize(0), actualReadBufferSize(0), stopped(true), readSequenceStarted(false), + notifiedCalled(false), pipeBroken(false), - readyReadEmitted(false) + readyReadPending(false), + inReadyRead(false) { - dataReadNotifier = new QWinOverlappedIoNotifier(this); - connect(dataReadNotifier, &QWinOverlappedIoNotifier::notified, this, &QWindowsPipeReader::notified); + connect(this, &QWindowsPipeReader::_q_queueReadyRead, + this, &QWindowsPipeReader::emitPendingReadyRead, Qt::QueuedConnection); } -static bool qt_cancelIo(HANDLE handle, OVERLAPPED *overlapped) +bool qt_cancelIo(HANDLE handle, OVERLAPPED *overlapped) { typedef BOOL (WINAPI *PtrCancelIoEx)(HANDLE, LPOVERLAPPED); static PtrCancelIoEx ptrCancelIoEx = 0; @@ -88,12 +100,6 @@ void QWindowsPipeReader::setHandle(HANDLE hPipeReadEnd) actualReadBufferSize = 0; handle = hPipeReadEnd; pipeBroken = false; - readyReadEmitted = false; - stopped = false; - if (hPipeReadEnd != INVALID_HANDLE_VALUE) { - dataReadNotifier->setHandle(hPipeReadEnd); - dataReadNotifier->setEnabled(true); - } } /*! @@ -104,19 +110,15 @@ void QWindowsPipeReader::stop() { stopped = true; if (readSequenceStarted) { - if (qt_cancelIo(handle, &overlapped)) { - dataReadNotifier->waitForNotified(-1, &overlapped); - } else { + if (!qt_cancelIo(handle, &overlapped)) { const DWORD dwError = GetLastError(); if (dwError != ERROR_NOT_FOUND) { qErrnoWarning(dwError, "QWindowsPipeReader: qt_cancelIo on handle %x failed.", handle); } } + waitForNotification(-1); } - readSequenceStarted = false; - dataReadNotifier->setEnabled(false); - handle = INVALID_HANDLE_VALUE; } /*! @@ -174,11 +176,10 @@ bool QWindowsPipeReader::canReadLine() const \internal Will be called whenever the read operation completes. */ -void QWindowsPipeReader::notified(quint32 numberOfBytesRead, quint32 errorCode, - OVERLAPPED *notifiedOverlapped) +void QWindowsPipeReader::notified(DWORD errorCode, DWORD numberOfBytesRead) { - if (&overlapped != notifiedOverlapped) - return; + notifiedCalled = true; + readSequenceStarted = false; switch (errorCode) { case ERROR_SUCCESS: @@ -202,8 +203,6 @@ void QWindowsPipeReader::notified(quint32 numberOfBytesRead, quint32 errorCode, break; } - readSequenceStarted = false; - // After the reader was stopped, the only reason why this function can be called is the // completion of a cancellation. No signals should be emitted, and no new read sequence should // be started in this case. @@ -218,13 +217,15 @@ void QWindowsPipeReader::notified(quint32 numberOfBytesRead, quint32 errorCode, actualReadBufferSize += numberOfBytesRead; readBuffer.truncate(actualReadBufferSize); startAsyncRead(); - readyReadEmitted = true; - emit readyRead(); + if (!readyReadPending) { + readyReadPending = true; + emit _q_queueReadyRead(QWindowsPipeReader::QPrivateSignal()); + } } /*! \internal - Reads data from the socket into the readbuffer + Reads data from the pipe into the readbuffer. */ void QWindowsPipeReader::startAsyncRead() { @@ -244,43 +245,41 @@ void QWindowsPipeReader::startAsyncRead() char *ptr = readBuffer.reserve(bytesToRead); + stopped = false; readSequenceStarted = true; - ZeroMemory(&overlapped, sizeof(overlapped)); - if (ReadFile(handle, ptr, bytesToRead, NULL, &overlapped)) { - // We get notified by the QWinOverlappedIoNotifier - even in the synchronous case. - return; - } else { + overlapped.clear(); + if (!ReadFileEx(handle, ptr, bytesToRead, &overlapped, &readFileCompleted)) { + readSequenceStarted = false; + const DWORD dwError = GetLastError(); switch (dwError) { - case ERROR_IO_PENDING: - // This is not an error. We're getting notified, when data arrives. - return; - case ERROR_MORE_DATA: - // This is not an error. The synchronous read succeeded. - // We're connected to a message mode pipe and the message - // didn't fit into the pipe's system buffer. - // We're getting notified by the QWinOverlappedIoNotifier. - break; case ERROR_BROKEN_PIPE: case ERROR_PIPE_NOT_CONNECTED: - { - // It may happen, that the other side closes the connection directly - // after writing data. Then we must set the appropriate socket state. - readSequenceStarted = false; - pipeBroken = true; - emit pipeClosed(); - return; - } + // It may happen, that the other side closes the connection directly + // after writing data. Then we must set the appropriate socket state. + pipeBroken = true; + emit pipeClosed(); + break; default: - readSequenceStarted = false; emit winError(dwError, QLatin1String("QWindowsPipeReader::startAsyncRead")); - return; + break; } } } /*! \internal + Called when ReadFileEx finished the read operation. + */ +void QWindowsPipeReader::readFileCompleted(DWORD errorCode, DWORD numberOfBytesTransfered, + OVERLAPPED *overlappedBase) +{ + Overlapped *overlapped = static_cast<Overlapped *>(overlappedBase); + overlapped->pipeReader->notified(errorCode, numberOfBytesTransfered); +} + +/*! + \internal Returns the number of available bytes in the pipe. Sets QWindowsPipeReader::pipeBroken to true if the connection is broken. */ @@ -298,17 +297,60 @@ DWORD QWindowsPipeReader::checkPipeState() return 0; } +bool QWindowsPipeReader::waitForNotification(int timeout) +{ + QElapsedTimer t; + t.start(); + notifiedCalled = false; + int msecs = timeout; + while (SleepEx(msecs == -1 ? INFINITE : msecs, TRUE) == WAIT_IO_COMPLETION) { + if (notifiedCalled) + return true; + + // Some other I/O completion routine was called. Wait some more. + msecs = qt_subtract_from_timeout(timeout, t.elapsed()); + if (!msecs) + break; + } + return notifiedCalled; +} + +void QWindowsPipeReader::emitPendingReadyRead() +{ + if (readyReadPending) { + readyReadPending = false; + inReadyRead = true; + emit readyRead(); + inReadyRead = false; + } +} + /*! Waits for the completion of the asynchronous read operation. - Returns \c true, if we've emitted the readyRead signal. + Returns \c true, if we've emitted the readyRead signal (non-recursive case) + or readyRead will be emitted by the event loop (recursive case). */ bool QWindowsPipeReader::waitForReadyRead(int msecs) { if (!readSequenceStarted) return false; - readyReadEmitted = false; - dataReadNotifier->waitForNotified(msecs, &overlapped); - return readyReadEmitted; + + if (readyReadPending) { + if (!inReadyRead) + emitPendingReadyRead(); + return true; + } + + if (!waitForNotification(msecs)) + return false; + + if (readyReadPending) { + if (!inReadyRead) + emitPendingReadyRead(); + return true; + } + + return false; } /*! |