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Diffstat (limited to 'src/corelib/io/qwinoverlappedionotifier.cpp')
| -rw-r--r-- | src/corelib/io/qwinoverlappedionotifier.cpp | 428 |
1 files changed, 0 insertions, 428 deletions
diff --git a/src/corelib/io/qwinoverlappedionotifier.cpp b/src/corelib/io/qwinoverlappedionotifier.cpp deleted file mode 100644 index d7745ae1b6..0000000000 --- a/src/corelib/io/qwinoverlappedionotifier.cpp +++ /dev/null @@ -1,428 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtCore module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#include "qwinoverlappedionotifier_p.h" -#include <qdebug.h> -#include <qatomic.h> -#include <qelapsedtimer.h> -#include <qmutex.h> -#include <qpointer.h> -#include <qqueue.h> -#include <qset.h> -#include <qthread.h> -#include <qt_windows.h> -#include <private/qobject_p.h> -#include <private/qiodevice_p.h> - -QT_BEGIN_NAMESPACE - -/*! - \class QWinOverlappedIoNotifier - \inmodule QtCore - \brief The QWinOverlappedIoNotifier class provides support for overlapped I/O notifications on Windows. - \since 5.0 - \internal - - The QWinOverlappedIoNotifier class makes it possible to use efficient - overlapped (asynchronous) I/O notifications on Windows by using an - I/O completion port. - - Once you have obtained a file handle, you can use setHandle() to get - notifications for I/O operations. Whenever an I/O operation completes, - the notified() signal is emitted which will pass the number of transferred - bytes, the operation's error code and a pointer to the operation's - OVERLAPPED object to the receiver. - - Every handle that supports overlapped I/O can be used by - QWinOverlappedIoNotifier. That includes file handles, TCP sockets - and named pipes. - - Note that you must not use ReadFileEx() and WriteFileEx() together - with QWinOverlappedIoNotifier. They are not supported as they use a - different I/O notification mechanism. - - The hEvent member in the OVERLAPPED structure passed to ReadFile() - or WriteFile() is ignored and can be used for other purposes. - - \warning This class is only available on Windows. - - Due to peculiarities of the Windows I/O completion port API, users of - QWinOverlappedIoNotifier must pay attention to the following restrictions: - \list - \li File handles with a QWinOverlappedIoNotifer are assigned to an I/O - completion port until the handle is closed. It is impossible to - disassociate the file handle from the I/O completion port. - \li There can be only one QWinOverlappedIoNotifer per file handle. Creating - another QWinOverlappedIoNotifier for that file, even with a duplicated - handle, will fail. - \li Certain Windows API functions are unavailable for file handles that are - assigned to an I/O completion port. This includes the functions - \c{ReadFileEx} and \c{WriteFileEx}. - \endlist - See also the remarks in the MSDN documentation for the - \c{CreateIoCompletionPort} function. -*/ - -struct IOResult -{ - IOResult(DWORD n = 0, DWORD e = 0, OVERLAPPED *p = 0) - : numberOfBytes(n), errorCode(e), overlapped(p) - {} - - DWORD numberOfBytes; - DWORD errorCode; - OVERLAPPED *overlapped; -}; - - -class QWinIoCompletionPort; - -class QWinOverlappedIoNotifierPrivate : public QObjectPrivate -{ - Q_DECLARE_PUBLIC(QWinOverlappedIoNotifier) -public: - QWinOverlappedIoNotifierPrivate() - : hHandle(INVALID_HANDLE_VALUE) - { - } - - OVERLAPPED *waitForAnyNotified(int msecs); - void notify(DWORD numberOfBytes, DWORD errorCode, OVERLAPPED *overlapped); - void _q_notified(); - OVERLAPPED *dispatchNextIoResult(); - - static QWinIoCompletionPort *iocp; - static HANDLE iocpInstanceLock; - static unsigned int iocpInstanceRefCount; - HANDLE hHandle; - HANDLE hSemaphore; - HANDLE hResultsMutex; - QAtomicInt waiting; - QQueue<IOResult> results; -}; - -QWinIoCompletionPort *QWinOverlappedIoNotifierPrivate::iocp = 0; -HANDLE QWinOverlappedIoNotifierPrivate::iocpInstanceLock = CreateMutex(NULL, FALSE, NULL); -unsigned int QWinOverlappedIoNotifierPrivate::iocpInstanceRefCount = 0; - - -class QWinIoCompletionPort : protected QThread -{ -public: - QWinIoCompletionPort() - : finishThreadKey(reinterpret_cast<ULONG_PTR>(this)), - drainQueueKey(reinterpret_cast<ULONG_PTR>(this + 1)), - hPort(INVALID_HANDLE_VALUE) - { - setObjectName(QLatin1String("I/O completion port thread")); - HANDLE hIOCP = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0); - if (!hIOCP) { - qErrnoWarning("CreateIoCompletionPort failed."); - return; - } - hPort = hIOCP; - hQueueDrainedEvent = CreateEvent(NULL, TRUE, FALSE, NULL); - if (!hQueueDrainedEvent) { - qErrnoWarning("CreateEvent failed."); - return; - } - } - - ~QWinIoCompletionPort() - { - PostQueuedCompletionStatus(hPort, 0, finishThreadKey, NULL); - QThread::wait(); - CloseHandle(hPort); - CloseHandle(hQueueDrainedEvent); - } - - void registerNotifier(QWinOverlappedIoNotifierPrivate *notifier) - { - const HANDLE hHandle = notifier->hHandle; - HANDLE hIOCP = CreateIoCompletionPort(hHandle, hPort, - reinterpret_cast<ULONG_PTR>(notifier), 0); - if (!hIOCP) { - qErrnoWarning("Can't associate file handle %x with I/O completion port.", hHandle); - return; - } - mutex.lock(); - notifiers += notifier; - mutex.unlock(); - if (!QThread::isRunning()) - QThread::start(); - } - - void unregisterNotifier(QWinOverlappedIoNotifierPrivate *notifier) - { - mutex.lock(); - notifiers.remove(notifier); - mutex.unlock(); - } - - void drainQueue() - { - QMutexLocker locker(&drainQueueMutex); - ResetEvent(hQueueDrainedEvent); - PostQueuedCompletionStatus(hPort, 0, drainQueueKey, NULL); - WaitForSingleObject(hQueueDrainedEvent, INFINITE); - } - - using QThread::isRunning; - -protected: - void run() - { - DWORD dwBytesRead; - ULONG_PTR pulCompletionKey; - OVERLAPPED *overlapped; - DWORD msecs = INFINITE; - - forever { - BOOL success = GetQueuedCompletionStatus(hPort, - &dwBytesRead, - &pulCompletionKey, - &overlapped, - msecs); - - DWORD errorCode = success ? ERROR_SUCCESS : GetLastError(); - if (!success && !overlapped) { - if (!msecs) { - // Time out in drain mode. The completion status queue is empty. - msecs = INFINITE; - SetEvent(hQueueDrainedEvent); - continue; - } - qErrnoWarning(errorCode, "GetQueuedCompletionStatus failed."); - return; - } - - if (pulCompletionKey == finishThreadKey) - return; - if (pulCompletionKey == drainQueueKey) { - // Enter drain mode. - Q_ASSERT(msecs == INFINITE); - msecs = 0; - continue; - } - - QWinOverlappedIoNotifierPrivate *notifier - = reinterpret_cast<QWinOverlappedIoNotifierPrivate *>(pulCompletionKey); - mutex.lock(); - if (notifiers.contains(notifier)) - notifier->notify(dwBytesRead, errorCode, overlapped); - mutex.unlock(); - } - } - -private: - const ULONG_PTR finishThreadKey; - const ULONG_PTR drainQueueKey; - HANDLE hPort; - QSet<QWinOverlappedIoNotifierPrivate *> notifiers; - QMutex mutex; - QMutex drainQueueMutex; - HANDLE hQueueDrainedEvent; -}; - - -QWinOverlappedIoNotifier::QWinOverlappedIoNotifier(QObject *parent) - : QObject(*new QWinOverlappedIoNotifierPrivate, parent) -{ - Q_D(QWinOverlappedIoNotifier); - WaitForSingleObject(d->iocpInstanceLock, INFINITE); - if (!d->iocp) - d->iocp = new QWinIoCompletionPort; - d->iocpInstanceRefCount++; - ReleaseMutex(d->iocpInstanceLock); - - d->hSemaphore = CreateSemaphore(NULL, 0, 255, NULL); - d->hResultsMutex = CreateMutex(NULL, FALSE, NULL); - connect(this, SIGNAL(_q_notify()), this, SLOT(_q_notified()), Qt::QueuedConnection); -} - -QWinOverlappedIoNotifier::~QWinOverlappedIoNotifier() -{ - Q_D(QWinOverlappedIoNotifier); - setEnabled(false); - CloseHandle(d->hResultsMutex); - CloseHandle(d->hSemaphore); - - WaitForSingleObject(d->iocpInstanceLock, INFINITE); - if (!--d->iocpInstanceRefCount) { - delete d->iocp; - d->iocp = 0; - } - ReleaseMutex(d->iocpInstanceLock); -} - -void QWinOverlappedIoNotifier::setHandle(Qt::HANDLE h) -{ - Q_D(QWinOverlappedIoNotifier); - d->hHandle = h; -} - -Qt::HANDLE QWinOverlappedIoNotifier::handle() const -{ - Q_D(const QWinOverlappedIoNotifier); - return d->hHandle; -} - -void QWinOverlappedIoNotifier::setEnabled(bool enabled) -{ - Q_D(QWinOverlappedIoNotifier); - if (enabled) - d->iocp->registerNotifier(d); - else - d->iocp->unregisterNotifier(d); -} - -OVERLAPPED *QWinOverlappedIoNotifierPrivate::waitForAnyNotified(int msecs) -{ - if (!iocp->isRunning()) { - qWarning("Called QWinOverlappedIoNotifier::waitForAnyNotified on inactive notifier."); - return 0; - } - - if (msecs == 0) - iocp->drainQueue(); - - const DWORD wfso = WaitForSingleObject(hSemaphore, msecs == -1 ? INFINITE : DWORD(msecs)); - switch (wfso) { - case WAIT_OBJECT_0: - return dispatchNextIoResult(); - case WAIT_TIMEOUT: - return 0; - default: - qErrnoWarning("QWinOverlappedIoNotifier::waitForAnyNotified: WaitForSingleObject failed."); - return 0; - } -} - -class QScopedAtomicIntIncrementor -{ -public: - QScopedAtomicIntIncrementor(QAtomicInt &i) - : m_int(i) - { - ++m_int; - } - - ~QScopedAtomicIntIncrementor() - { - --m_int; - } - -private: - QAtomicInt &m_int; -}; - -/*! - * Wait synchronously for any notified signal. - * - * The function returns a pointer to the OVERLAPPED object corresponding to the completed I/O - * operation. In case no I/O operation was completed during the \a msec timeout, this function - * returns a null pointer. - */ -OVERLAPPED *QWinOverlappedIoNotifier::waitForAnyNotified(int msecs) -{ - Q_D(QWinOverlappedIoNotifier); - QScopedAtomicIntIncrementor saii(d->waiting); - OVERLAPPED *result = d->waitForAnyNotified(msecs); - return result; -} - -/*! - * Wait synchronously for the notified signal. - * - * The function returns true if the notified signal was emitted for - * the I/O operation that corresponds to the OVERLAPPED object. - */ -bool QWinOverlappedIoNotifier::waitForNotified(int msecs, OVERLAPPED *overlapped) -{ - Q_D(QWinOverlappedIoNotifier); - QScopedAtomicIntIncrementor saii(d->waiting); - int t = msecs; - QElapsedTimer stopWatch; - stopWatch.start(); - forever { - OVERLAPPED *triggeredOverlapped = waitForAnyNotified(t); - if (!triggeredOverlapped) - return false; - if (triggeredOverlapped == overlapped) - return true; - t = qt_subtract_from_timeout(msecs, stopWatch.elapsed()); - if (t == 0) - return false; - } -} - -/*! - * Note: This function runs in the I/O completion port thread. - */ -void QWinOverlappedIoNotifierPrivate::notify(DWORD numberOfBytes, DWORD errorCode, - OVERLAPPED *overlapped) -{ - Q_Q(QWinOverlappedIoNotifier); - WaitForSingleObject(hResultsMutex, INFINITE); - results.enqueue(IOResult(numberOfBytes, errorCode, overlapped)); - ReleaseMutex(hResultsMutex); - ReleaseSemaphore(hSemaphore, 1, NULL); - if (!waiting) - emit q->_q_notify(); -} - -void QWinOverlappedIoNotifierPrivate::_q_notified() -{ - if (WaitForSingleObject(hSemaphore, 0) == WAIT_OBJECT_0) - dispatchNextIoResult(); -} - -OVERLAPPED *QWinOverlappedIoNotifierPrivate::dispatchNextIoResult() -{ - Q_Q(QWinOverlappedIoNotifier); - WaitForSingleObject(hResultsMutex, INFINITE); - IOResult ioresult = results.dequeue(); - ReleaseMutex(hResultsMutex); - emit q->notified(ioresult.numberOfBytes, ioresult.errorCode, ioresult.overlapped); - return ioresult.overlapped; -} - -QT_END_NAMESPACE - -#include "moc_qwinoverlappedionotifier_p.cpp" |