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

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#include "readmessageblock.h"

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

namespace ClangBackEnd {

ReadMessageBlock::ReadMessageBlock(QIODevice *ioDevice)
    : ioDevice(ioDevice),
      messageCounter(0),
      blockSize(0)
{
}

void ReadMessageBlock::checkIfMessageIsLost(QDataStream &in)
{
    qint64 currentMessageCounter;

    in >> currentMessageCounter;

#ifndef DONT_CHECK_MESSAGE_COUNTER
    bool messageLost = !((currentMessageCounter == 0 && messageCounter == 0) || (messageCounter + 1 == currentMessageCounter));
    if (messageLost)
        qWarning() << "client message lost: " << messageCounter <<  currentMessageCounter;
#endif

    messageCounter = currentMessageCounter;
}

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

    QVariant message;

    if (isTheWholeMessageReadable(in)) {
        checkIfMessageIsLost(in);
        in >> message;
    }

    return message;
}

QVector<QVariant> ReadMessageBlock::readAll()
{
    QVector<QVariant> messages;

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

    Q_UNREACHABLE();
}

void ReadMessageBlock::resetCounter()
{
    messageCounter = 0;
}

bool ReadMessageBlock::isTheWholeMessageReadable(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