今天测试发现qwebsocket有个bug

发现命令使用时间久了就会丢失mask，mask设置成0,而websocket协议要求客户端给服务器传东西必须带mask=1，发现确实有个bug,代码如下：

文件：src/websockets/qwebsocket_p.cpp 这个函数有可能返回0

quint32 QWebSocketPrivate::generateMaskingKey() const
{
return m_pMaskGenerator->nextMask();
}
文件：src/websockets/qdefaultmaskgenerator_p.cpp

quint32 QDefaultMaskGenerator::nextMask() Q_DECL_NOEXCEPT
{
return quint32((double(qrand()) / RAND_MAX) * std::numeric_limits<quint32>::max());
}

而调用他的地方：

/*!
* \internal
*/
QByteArray QWebSocketPrivate::getFrameHeader(QWebSocketProtocol::OpCode opCode,
quint64 payloadLength, quint32 maskingKey,
bool lastFrame)
{
QByteArray header;
quint8 byte = 0x00;
bool ok = payloadLength <= 0x7FFFFFFFFFFFFFFFULL;

if (Q_LIKELY(ok)) {
//FIN, RSV1-3, opcode (RSV-1, RSV-2 and RSV-3 are zero)
byte = static_cast<quint8>((opCode & 0x0F) | (lastFrame ? 0x80 : 0x00));
header.append(static_cast<char>(byte));

byte = 0x00;
if (maskingKey != 0)
byte |= 0x80;
if (payloadLength <= 125) {
byte |= static_cast<quint8>(payloadLength);
header.append(static_cast<char>(byte));
} else if (payloadLength <= 0xFFFFU) {
byte |= 126;
header.append(static_cast<char>(byte));
quint16 swapped = qToBigEndian<quint16>(static_cast<quint16>(payloadLength));
header.append(static_cast<const char *>(static_cast<const void *>(&swapped)), 2);
} else if (payloadLength <= 0x7FFFFFFFFFFFFFFFULL) {
byte |= 127;
header.append(static_cast<char>(byte));
quint64 swapped = qToBigEndian<quint64>(payloadLength);
header.append(static_cast<const char *>(static_cast<const void *>(&swapped)), 8);
}

if (maskingKey != 0) {
const quint32 mask = qToBigEndian<quint32>(maskingKey);
header.append(static_cast<const char *>(static_cast<const void *>(&mask)),
sizeof(quint32));
}
} else {
setErrorString(QStringLiteral("WebSocket::getHeader: payload too big!"));
Q_EMIT q_ptr->error(QAbstractSocket::DatagramTooLargeError);
}

return header;
}

很明显这个值在随机的时候可能出现0，而出现0的时候就出错了