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#include "qlocalsocket_p.h"

#include <private/qthread_p.h>

#include <qcoreapplication.h>

#include <qdebug.h>

QT_BEGIN_NAMESPACE

void QLocalSocketPrivate::init()

{

    Q_Q(QLocalSocket);

    memset(&overlapped, 0, sizeof(overlapped));

    overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

    dataReadNotifier = new QWinEventNotifier(overlapped.hEvent, q);

    q->connect(dataReadNotifier, SIGNAL(activated(HANDLE)), q, SLOT(_q_notified()));

}

void QLocalSocketPrivate::setErrorString(const QString &function)

{

    Q_Q(QLocalSocket);

    BOOL windowsError = GetLastError();

    QLocalSocket::LocalSocketState currentState = state;

    // If the connectToServer fails due to WaitNamedPipe() time-out, assume ConnectionError  

    if (state == QLocalSocket::ConnectingState && windowsError == ERROR_SEM_TIMEOUT)

        windowsError = ERROR_NO_DATA;

    switch (windowsError) {

    case ERROR_PIPE_NOT_CONNECTED:

    case ERROR_BROKEN_PIPE:

    case ERROR_NO_DATA:

        error = QLocalSocket::ConnectionError;

        errorString = QLocalSocket::tr("%1: Connection error").arg(function);

        state = QLocalSocket::UnconnectedState;

        break;

    case ERROR_FILE_NOT_FOUND:

        error = QLocalSocket::ServerNotFoundError;

        errorString = QLocalSocket::tr("%1: Invalid name").arg(function);

        state = QLocalSocket::UnconnectedState;

        break;

    default:

        error = QLocalSocket::UnknownSocketError;

        errorString = QLocalSocket::tr("%1: Unknown error %2").arg(function).arg(windowsError);

#if defined QLOCALSOCKET_DEBUG

        qWarning() << "QLocalSocket error not handled:" << errorString;

#endif

        state = QLocalSocket::UnconnectedState;

    }

    if (currentState != state) {

        q->emit stateChanged(state);

        if (state == QLocalSocket::UnconnectedState)

            q->emit disconnected();

    }

    emit q->error(error);

}

QLocalSocketPrivate::QLocalSocketPrivate() : QIODevicePrivate(),

       handle(INVALID_HANDLE_VALUE),

       pipeWriter(0),

       readBufferMaxSize(0),

       actualReadBufferSize(0),

       error(QLocalSocket::UnknownSocketError),

       readSequenceStarted(false),

       pendingReadyRead(false),

       pipeClosed(false),

       state(QLocalSocket::UnconnectedState)

{

}

QLocalSocketPrivate::~QLocalSocketPrivate()

{

    destroyPipeHandles();

    CloseHandle(overlapped.hEvent);

}

void QLocalSocketPrivate::destroyPipeHandles()

{

    if (handle != INVALID_HANDLE_VALUE) {

        DisconnectNamedPipe(handle);

        CloseHandle(handle);

    }

}

void QLocalSocket::connectToServer(const QString &name, OpenMode openMode)

{

    Q_D(QLocalSocket);

    if (state() == ConnectedState || state() == ConnectingState)

        return;

    d->error = QLocalSocket::UnknownSocketError;

    d->errorString = QString();

    d->state = ConnectingState;

    emit stateChanged(d->state);

    if (name.isEmpty()) {

        d->error = QLocalSocket::ServerNotFoundError;

        setErrorString(QLocalSocket::tr("%1: Invalid name").arg(QLatin1String("QLocalSocket::connectToServer")));

        d->state = UnconnectedState;

        emit error(d->error);

        emit stateChanged(d->state);

        return;

    }

    QString pipePath = QLatin1String("\\\\.\\pipe\\");

    if (name.startsWith(pipePath))

        d->fullServerName = name;

    else

        d->fullServerName = pipePath + name;

    // Try to open a named pipe

    HANDLE localSocket;

    forever {

        DWORD permissions = (openMode & QIODevice::ReadOnly) ? GENERIC_READ : 0;

        permissions |= (openMode & QIODevice::WriteOnly) ? GENERIC_WRITE : 0;

        localSocket = CreateFile((const wchar_t *)d->fullServerName.utf16(),   // pipe name

                                 permissions,

                                 0,              // no sharing

                                 NULL,           // default security attributes

                                 OPEN_EXISTING,  // opens existing pipe

                                 FILE_FLAG_OVERLAPPED,

                                 NULL);          // no template file

        if (localSocket != INVALID_HANDLE_VALUE)

            break;

        DWORD error = GetLastError();

        // It is really an error only if it is not ERROR_PIPE_BUSY

        if (ERROR_PIPE_BUSY != error) {

            break;

        }

        // All pipe instances are busy, so wait until connected or up to 5 seconds.

        if (!WaitNamedPipe((const wchar_t *)d->fullServerName.utf16(), 5000))

            break;

    }

    if (localSocket == INVALID_HANDLE_VALUE) {

        d->setErrorString(QLatin1String("QLocalSocket::connectToServer"));

        d->fullServerName = QString();

        return;

    }

    // we have a valid handle

    d->serverName = name;

    if (setSocketDescriptor((quintptr)localSocket, ConnectedState, openMode)) {

        d->handle = localSocket;

        emit connected();

    }

}

// This is reading from the buffer

qint64 QLocalSocket::readData(char *data, qint64 maxSize)

{

    Q_D(QLocalSocket);

    if (d->pipeClosed && d->actualReadBufferSize == 0)

        return -1;  // signal EOF

    qint64 readSoFar;

    // If startAsyncRead() read data, copy it to its destination.

    if (maxSize == 1 && d->actualReadBufferSize > 0) {

        *data = d->readBuffer.getChar();

        d->actualReadBufferSize--;

        readSoFar = 1;

    } else {

        qint64 bytesToRead = qMin(qint64(d->actualReadBufferSize), maxSize);

        readSoFar = 0;

        while (readSoFar < bytesToRead) {

            const char *ptr = d->readBuffer.readPointer();

            int bytesToReadFromThisBlock = qMin(bytesToRead - readSoFar,

                                                qint64(d->readBuffer.nextDataBlockSize()));

            memcpy(data + readSoFar, ptr, bytesToReadFromThisBlock);

            readSoFar += bytesToReadFromThisBlock;

            d->readBuffer.free(bytesToReadFromThisBlock);

            d->actualReadBufferSize -= bytesToReadFromThisBlock;

        }

    }

    if (d->pipeClosed) {

        if (d->actualReadBufferSize == 0)

            QTimer::singleShot(0, this, SLOT(_q_pipeClosed()));

    } else {

        if (!d->readSequenceStarted)

            d->startAsyncRead();

        d->checkReadyRead();

    }

    return readSoFar;

}

/*!

    \internal

    Schedules or cancels a readyRead() emission depending on actual data availability

 */

void QLocalSocketPrivate::checkReadyRead()

{

    if (actualReadBufferSize > 0) {

        if (!pendingReadyRead) {

            Q_Q(QLocalSocket);

            QTimer::singleShot(0, q, SLOT(_q_emitReadyRead()));

            pendingReadyRead = true;

        }

    } else {

        pendingReadyRead = false;

    }

}

/*!

    \internal

    Reads data from the socket into the readbuffer

 */

void QLocalSocketPrivate::startAsyncRead()

{

    do {

        DWORD bytesToRead = checkPipeState();

        if (pipeClosed)

            return;

        if (bytesToRead == 0) {

            // There are no bytes in the pipe but we need to

            // start the overlapped read with some buffer size.

            bytesToRead = initialReadBufferSize;

        }

        if (readBufferMaxSize && bytesToRead > (readBufferMaxSize - readBuffer.size())) {

            bytesToRead = readBufferMaxSize - readBuffer.size();

            if (bytesToRead == 0) {

                // Buffer is full. User must read data from the buffer

                // before we can read more from the pipe.

                return;

            }

        }

        char *ptr = readBuffer.reserve(bytesToRead);

        readSequenceStarted = true;

        if (ReadFile(handle, ptr, bytesToRead, NULL, &overlapped)) {

            completeAsyncRead();

        } else {

            switch (GetLastError()) {

                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.

                    completeAsyncRead();

                    break;

                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.

                        pipeClosed = true;

                        Q_Q(QLocalSocket);

                        emit q->readChannelFinished();

                        return;

                    }

                default:

                    setErrorString(QLatin1String("QLocalSocketPrivate::startAsyncRead"));

                    return;

            }

        }

    } while (!readSequenceStarted);

}

/*!

    \internal

    Sets the correct size of the read buffer after a read operation.

 */

bool QLocalSocketPrivate::completeAsyncRead()

{

    ResetEvent(overlapped.hEvent);

    readSequenceStarted = false;

    DWORD bytesRead;

    if (!GetOverlappedResult(handle, &overlapped, &bytesRead, TRUE)) {

        switch (GetLastError()) {

        case ERROR_MORE_DATA:

            // This is not an error. We're connected to a message mode

            // pipe and the message didn't fit into the pipe's system

            // buffer. We will read the remaining data in the next call.

            break;

        case ERROR_PIPE_NOT_CONNECTED:

            setErrorString(QLatin1String("QLocalSocketPrivate::completeAsyncRead"));

            // fall through

        default:

            return false;

        }

    }

    actualReadBufferSize += bytesRead;

    readBuffer.truncate(actualReadBufferSize);

    return true;

}

qint64 QLocalSocket::writeData(const char *data, qint64 maxSize)

{

    Q_D(QLocalSocket);

    if (!d->pipeWriter) {

        d->pipeWriter = new QWindowsPipeWriter(d->handle, this);

        connect(d->pipeWriter, SIGNAL(canWrite()), this, SLOT(_q_canWrite()));

        connect(d->pipeWriter, SIGNAL(bytesWritten(qint64)), this, SIGNAL(bytesWritten(qint64)));

        d->pipeWriter->start();

    }

    return d->pipeWriter->write(data, maxSize);

}

void QLocalSocket::abort()

{

    close();

}

/*!

    \internal

    Returns the number of available bytes in the pipe.

    Sets QLocalSocketPrivate::pipeClosed to true if the connection is broken.

 */

DWORD QLocalSocketPrivate::checkPipeState()

{

    Q_Q(QLocalSocket);

    DWORD bytes;

    if (PeekNamedPipe(handle, NULL, 0, NULL, &bytes, NULL)) {

        return bytes;

    } else {

        if (!pipeClosed) {

            pipeClosed = true;

            emit q->readChannelFinished();

            if (actualReadBufferSize == 0)

                QTimer::singleShot(0, q, SLOT(_q_pipeClosed()));

        }

    }

    return 0;

}

void QLocalSocketPrivate::_q_pipeClosed()

{

    Q_Q(QLocalSocket);

    q->close();

}

qint64 QLocalSocket::bytesAvailable() const

{

    Q_D(const QLocalSocket);

    qint64 available = QIODevice::bytesAvailable();

    available += (qint64) d->actualReadBufferSize;

    return available;

}

qint64 QLocalSocket::bytesToWrite() const

{

    Q_D(const QLocalSocket);

    return (d->pipeWriter) ? d->pipeWriter->bytesToWrite() : 0;

}

bool QLocalSocket::canReadLine() const

{

    Q_D(const QLocalSocket);

    if (state() != ConnectedState)

        return false;

    return (QIODevice::canReadLine()

            || d->readBuffer.indexOf('\n', d->actualReadBufferSize) != -1);

}

void QLocalSocket::close()

{

    Q_D(QLocalSocket);

    if (state() == UnconnectedState)

        return;

    QIODevice::close();

    d->state = ClosingState;

    emit stateChanged(d->state);

    if (!d->pipeClosed)

        emit readChannelFinished();

    d->serverName = QString();

    d->fullServerName = QString();

    if (state() != UnconnectedState && bytesToWrite() > 0) {

        disconnectFromServer();

        return;

    }

    d->readSequenceStarted = false;

    d->pendingReadyRead = false;

    d->pipeClosed = false;

    d->destroyPipeHandles();

    d->handle = INVALID_HANDLE_VALUE;

    ResetEvent(d->overlapped.hEvent);

    d->state = UnconnectedState;

    emit stateChanged(d->state);

    emit disconnected();

    if (d->pipeWriter) {

        delete d->pipeWriter;

        d->pipeWriter = 0;

    }

}

bool QLocalSocket::flush()

{

    Q_D(QLocalSocket);

    if (d->pipeWriter)

        return d->pipeWriter->waitForWrite(0);

    return false;

}

void QLocalSocket::disconnectFromServer()

{

    Q_D(QLocalSocket);

    // Are we still connected?

    if (!isValid()) {

        // If we have unwritten data, the pipeWriter is still present.

        // It must be destroyed before close() to prevent an infinite loop.

        delete d->pipeWriter;

        d->pipeWriter = 0;

    }

    flush();

    if (d->pipeWriter && d->pipeWriter->bytesToWrite() != 0) {

        d->state = QLocalSocket::ClosingState;

        emit stateChanged(d->state);

    } else {

        close();

    }

}

QLocalSocket::LocalSocketError QLocalSocket::error() const

{

    Q_D(const QLocalSocket);

    return d->error;

}

bool QLocalSocket::setSocketDescriptor(quintptr socketDescriptor,

              LocalSocketState socketState, OpenMode openMode)

{

    Q_D(QLocalSocket);

    d->readBuffer.clear();

    d->actualReadBufferSize = 0;

    QIODevice::open(openMode);

    d->handle = (int*)socketDescriptor;

    d->state = socketState;

    emit stateChanged(d->state);

    if (d->state == ConnectedState && openMode.testFlag(QIODevice::ReadOnly)) {

        d->startAsyncRead();

        d->checkReadyRead();

    }

    return true;

}

void QLocalSocketPrivate::_q_canWrite()

{

    Q_Q(QLocalSocket);

    if (state == QLocalSocket::ClosingState)

        q->close();

}

void QLocalSocketPrivate::_q_notified()

{

    Q_Q(QLocalSocket);

    if (!completeAsyncRead()) {

        pipeClosed = true;

        emit q->readChannelFinished();

        if (actualReadBufferSize == 0)

            QTimer::singleShot(0, q, SLOT(_q_pipeClosed()));

        return;

    }

    startAsyncRead();

    pendingReadyRead = false;

    emit q->readyRead();

}

void QLocalSocketPrivate::_q_emitReadyRead()

{

    if (pendingReadyRead) {

        Q_Q(QLocalSocket);

        pendingReadyRead = false;

        emit q->readyRead();

    }

}

quintptr QLocalSocket::socketDescriptor() const

{