qprocess.cpp

奇趣公司比较新的qt/emd版本

    if (deathNotifier) {
        deathNotifier->setEnabled(false);
        delete deathNotifier;
        deathNotifier = 0;
    }
    if (notifier) {
        delete notifier;
        notifier = 0;
    }
    destroyPipe(stdoutChannel.pipe);
    destroyPipe(stderrChannel.pipe);
    destroyPipe(stdinChannel.pipe);
    destroyPipe(childStartedPipe);
    destroyPipe(deathPipe);
#ifdef Q_OS_UNIX
    serial = 0;
#endif
}

/*! \internal
*/
bool QProcessPrivate::_q_canReadStandardOutput()
{
    Q_Q(QProcess);
    qint64 available = bytesAvailableFromStdout();
    if (available == 0) {
        if (stdoutChannel.notifier)
            stdoutChannel.notifier->setEnabled(false);
        destroyPipe(stdoutChannel.pipe);
#if defined QPROCESS_DEBUG
        qDebug("QProcessPrivate::canReadStandardOutput(), 0 bytes available");
#endif
        return false;
    }

    char *ptr = outputReadBuffer.reserve(available);
    qint64 readBytes = readFromStdout(ptr, available);
    if (readBytes == -1) {
        processError = QProcess::ReadError;
        q->setErrorString(QT_TRANSLATE_NOOP(QProcess, QLatin1String("Error reading from process")));
        emit q->error(processError);
#if defined QPROCESS_DEBUG
        qDebug("QProcessPrivate::canReadStandardOutput(), failed to read from the process");
#endif
        return false;
    }
#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::canReadStandardOutput(), read %d bytes from the process' output",
            int(readBytes));
#endif

    if (stdoutChannel.closed) {
        outputReadBuffer.chop(readBytes);
        return false;
    }

    outputReadBuffer.chop(available - readBytes);

    bool didRead = false;
    if (readBytes == 0) {
        if (stdoutChannel.notifier)
            stdoutChannel.notifier->setEnabled(false);
    } else if (processChannel == QProcess::StandardOutput) {
        didRead = true;
        if (!emittedReadyRead) {
            emittedReadyRead = true;
            emit q->readyRead();
            emittedReadyRead = false;
        }
    }
    emit q->readyReadStandardOutput();
    return didRead;
}

/*! \internal
*/
bool QProcessPrivate::_q_canReadStandardError()
{
    Q_Q(QProcess);
    qint64 available = bytesAvailableFromStderr();
    if (available == 0) {
        if (stderrChannel.notifier)
            stderrChannel.notifier->setEnabled(false);
        destroyPipe(stderrChannel.pipe);
        return false;
    }

    char *ptr = errorReadBuffer.reserve(available);
    qint64 readBytes = readFromStderr(ptr, available);
    if (readBytes == -1) {
        processError = QProcess::ReadError;
        q->setErrorString(QT_TRANSLATE_NOOP(QProcess, QLatin1String("Error reading from process")));
        emit q->error(processError);
        return false;
    }
    if (stderrChannel.closed) {
        errorReadBuffer.chop(readBytes);
        return false;
    }

    errorReadBuffer.chop(available - readBytes);

    bool didRead = false;
    if (readBytes == 0) {
        if (stderrChannel.notifier)
            stderrChannel.notifier->setEnabled(false);
    } else if (processChannel == QProcess::StandardError) {
        didRead = true;
        if (!emittedReadyRead) {
            emittedReadyRead = true;
            emit q->readyRead();
            emittedReadyRead = false;
        }
    }
    emit q->readyReadStandardError();
    return didRead;
}

/*! \internal
*/
bool QProcessPrivate::_q_canWrite()
{
    Q_Q(QProcess);
    if (stdinChannel.notifier)
        stdinChannel.notifier->setEnabled(false);

    if (writeBuffer.isEmpty()) {
#if defined QPROCESS_DEBUG
        qDebug("QProcessPrivate::canWrite(), not writing anything (empty write buffer).");
#endif
        return false;
    }

    qint64 written = writeToStdin(writeBuffer.readPointer(),
                                      writeBuffer.nextDataBlockSize());
    if (written < 0) {
        destroyPipe(stdinChannel.pipe);
        processError = QProcess::WriteError;
        q->setErrorString(QT_TRANSLATE_NOOP(QProcess, QLatin1String("Error writing to process")));
#if defined QPROCESS_DEBUG
        qDebug("QProcessPrivate::canWrite(), failed to write (%s)", strerror(errno));
#endif
        emit q->error(processError);
        return false;
    }

#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::canWrite(), wrote %d bytes to the process input", int(written));
#endif

    writeBuffer.free(written);
    if (!emittedBytesWritten) {
        emittedBytesWritten = true;
        emit q->bytesWritten(written);
        emittedBytesWritten = false;
    }
    if (stdinChannel.notifier && !writeBuffer.isEmpty())
        stdinChannel.notifier->setEnabled(true);
    if (writeBuffer.isEmpty() && stdinChannel.closed)
        closeWriteChannel();
    return true;
}

/*! \internal
*/
bool QProcessPrivate::_q_processDied()
{
    Q_Q(QProcess);
#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::_q_processDied()");
#endif
#ifdef Q_OS_UNIX
    if (!waitForDeadChild())
        return false;
#endif
#ifdef Q_OS_WIN
    if (processFinishedNotifier)
        processFinishedNotifier->setEnabled(false);
#endif

    // the process may have died before it got a chance to report that it was
    // either running or stopped, so we will call _q_startupNotification() and
    // give it a chance to emit started() or error(FailedToStart).
    if (processState == QProcess::Starting) {
        if (!_q_startupNotification())
            return true;
    }

    if (dying) {
        // at this point we know the process is dead. prevent
        // reentering this slot recursively by calling waitForFinished()
        // or opening a dialog inside slots connected to the readyRead
        // signals emitted below.
        return true;
    }
    dying = true;
    
    // in case there is data in the pipe line and this slot by chance
    // got called before the read notifications, call these two slots
    // so the data is made available before the process dies.
    _q_canReadStandardOutput();
    _q_canReadStandardError();

    findExitCode();

    if (crashed) {
        exitStatus = QProcess::CrashExit;
        processError = QProcess::Crashed;
        q->setErrorString(QT_TRANSLATE_NOOP(QProcess, QLatin1String("Process crashed")));
        emit q->error(processError);
    }

    bool wasRunning = (processState == QProcess::Running);

    cleanup();

    processState = QProcess::NotRunning;
    emit q->stateChanged(processState);
    if (wasRunning) {
        emit q->finished(exitCode);
        emit q->finished(exitCode, exitStatus);
    }
#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::_q_processDied() process is dead");
#endif
    return true;
}

/*! \internal
*/
bool QProcessPrivate::_q_startupNotification()
{
    Q_Q(QProcess);
#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::startupNotification()");
#endif

    if (startupSocketNotifier)
        startupSocketNotifier->setEnabled(false);
    if (processStarted()) {
        processState = QProcess::Running;
        emit q->started();
        return true;
    }

    processState = QProcess::NotRunning;
    processError = QProcess::FailedToStart;
    emit q->error(processError);
#ifdef Q_OS_UNIX
    // make sure the process manager removes this entry
    waitForDeadChild();
    findExitCode();
#endif
    cleanup();
    return false;
}

/*! \internal
*/
void QProcessPrivate::closeWriteChannel()
{
#if defined QPROCESS_DEBUG
    qDebug("QProcessPrivate::closeWriteChannel()");
#endif
    if (stdinChannel.notifier) {
        stdinChannel.notifier->setEnabled(false);
        delete stdinChannel.notifier;
        stdinChannel.notifier = 0;
    }
#ifdef Q_OS_WIN
    // ### Find a better fix, feeding the process little by little
    // instead.
    flushPipeWriter();
#endif
    destroyPipe(stdinChannel.pipe);
}

/*!
    Constructs a QProcess object with the given \a parent.
*/
QProcess::QProcess(QObject *parent)
    : QIODevice(*new QProcessPrivate, parent)
{
#if defined QPROCESS_DEBUG
    qDebug("QProcess::QProcess(%p)", parent);
#endif
}

/*!
    Destructs the QProcess object, i.e., killing the process.

    Note that this function will not return until the process is
    terminated.
*/
QProcess::~QProcess()
{
    Q_D(QProcess);
    if (d->processState != NotRunning) {
        qWarning("QProcess: Destroyed while process is still running.");
        kill();
        waitForFinished();
    }
#ifdef Q_OS_UNIX
    // make sure the process manager removes this entry
    d->findExitCode();
#endif
    d->cleanup();
}

/*!
    \obsolete
    Returns the read channel mode of the QProcess. This function is
    equivalent to processChannelMode()

    \sa processChannelMode()
*/
QProcess::ProcessChannelMode QProcess::readChannelMode() const
{
    return processChannelMode();
}

/*!
    \obsolete

    Use setProcessChannelMode(\a mode) instead.

    \sa setProcessChannelMode()
*/
void QProcess::setReadChannelMode(ProcessChannelMode mode)
{
    setProcessChannelMode(mode);
}

/*!
    \since 4.2

    Returns the channel mode of the QProcess standard output and
    standard error channels.

    \sa setReadChannelMode(), ProcessChannelMode, setReadChannel()
*/
QProcess::ProcessChannelMode QProcess::processChannelMode() const
{
    Q_D(const QProcess);
    return d->processChannelMode;
}

/*!
    \since 4.2

    Sets the channel mode of the QProcess standard output and standard
    error channels to the \a mode specified.
    This mode will be used the next time start() is called. For example:

    \code
        QProcess builder;
        builder.setProcessChannelMode(QProcess::MergedChannels);
        builder.start("make", QStringList() << "-j2");

        if (!builder.waitForFinished())
            qDebug() << "Make failed:" << builder.errorString();
        else
            qDebug() << "Make output:" << builder.readAll();
    \endcode

    \sa readChannelMode(), ProcessChannelMode, setReadChannel()
*/
void QProcess::setProcessChannelMode(ProcessChannelMode mode)
{
    Q_D(QProcess);
    d->processChannelMode = mode;
}

/*!
    Returns the current read channel of the QProcess.

    \sa setReadChannel()
*/
QProcess::ProcessChannel QProcess::readChannel() const
{
    Q_D(const QProcess);
    return d->processChannel;
}

/*!
    Sets the current read channel of the QProcess to the given \a
    channel. The current input channel is used by the functions
    read(), readAll(), readLine(), and getChar(). It also determines
    which channel triggers QProcess to emit readyRead().

    \sa readChannel()
*/
void QProcess::setReadChannel(ProcessChannel channel)
{
    Q_D(QProcess);
    if (d->processChannel != channel) {
        QByteArray buf = d->buffer.readAll();
        if (d->processChannel == QProcess::StandardOutput) {
            for (int i = buf.size() - 1; i >= 0; --i)
                d->outputReadBuffer.ungetChar(buf.at(i));
        } else {
            for (int i = buf.size() - 1; i >= 0; --i)
                d->errorReadBuffer.ungetChar(buf.at(i));
        }
    }
    d->processChannel = channel;
}

/*!
    Closes the read channel \a channel. After calling this function,
    QProcess will no longer receive data on the channel. Any data that
    has already been received is still available for reading.

    Call this function to save memory, if you are not interested in
    the output of the process.

    \sa closeWriteChannel(), setReadChannel()
*/
void QProcess::closeReadChannel(ProcessChannel channel)
{
    Q_D(QProcess);

    if (channel == StandardOutput)
        d->stdoutChannel.closed = true;
    else
        d->stderrChannel.closed = true;
}

/*!
    Schedules the write channel of QProcess to be closed. The channel
    will close once all data has been written to the process. After
    calling this function, any attempts to write to the process will
    fail.

    Closing the write channel is necessary for programs that read
    input data until the channel has been closed. For example, the
    program "more" is used to display text data in a console on both
    Unix and Windows. But it will not display the text data until
    QProcess's write channel has been closed. Example:

    \code
        QProcess more;
        more.start("more");
        more.write("Text to display");
        more.closeWriteChannel();
        // QProcess will emit readyRead() once "more" starts printing
    \endcode

    The write channel is implicitly opened when start() is called.

    \sa closeReadChannel()