qt-creator/src/libs/clangbackendipc/readcommandblock.cpp

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#include "readcommandblock.h"

#include <QDataStream>
#include <QDebug>
#include <QIODevice>
#include <QVariant>

namespace ClangBackEnd {

ReadCommandBlock::ReadCommandBlock(QIODevice *ioDevice)
    : ioDevice(ioDevice),
      commandCounter(0),
      blockSize(0)
{
}

void ReadCommandBlock::checkIfCommandIsLost(QDataStream &in)
{
    qint64 currentCommandCounter;

    in >> currentCommandCounter;

#ifndef DONT_CHECK_COMMAND_COUNTER
    bool commandLost = !((currentCommandCounter == 0 && commandCounter == 0) || (commandCounter + 1 == currentCommandCounter));
    if (commandLost)
        qWarning() << "client command lost: " << commandCounter <<  currentCommandCounter;
#endif

    commandCounter = currentCommandCounter;
}

QVariant ReadCommandBlock::read()
{
    QDataStream in(ioDevice);

    QVariant command;

    if (isTheWholeCommandReadable(in)) {
        checkIfCommandIsLost(in);
        in >> command;
    }

    return command;
}

QVector<QVariant> ReadCommandBlock::readAll()
{
    QVector<QVariant> commands;

    while (true) {
        const QVariant command = read();
        if (command.isValid())
            commands.append(command);
        else
            return commands;
    }

    Q_UNREACHABLE();
}

void ReadCommandBlock::resetCounter()
{
    commandCounter = 0;
}

bool ReadCommandBlock::isTheWholeCommandReadable(QDataStream &in)
{
    if (ioDevice->bytesAvailable() == 0)
        return false;

    if (blockSize == 0)
        in >> blockSize;

    if (ioDevice->bytesAvailable() < blockSize)
        return false;

    blockSize = 0;

    return true;
}

} // namespace ClangBackEnd