QmlDebug: Restructure QPacket and QPacketProtocol

We cannot use the same data stream version for the client and server
versions of QPacket and QPacketProtocol should not deal with QPackets
but with simple byte arrays because the underlying QDataStream is hard
to copy.

The new QQmlDebugPacket picks its data stream version from
QQmlDebugConnector now, which adjusts it when connecting. As there can
only ever be one QQmlDebugConnector, we can keep the version static.

The clients need to query the connection for the correct version. We
may connect to several different servers sequentially or we may have a
server running while using a client, and we don't want to confuse the
versions between those.

With this in place, all remaining occurrences of QDataStream are
replaced with QPacket or QQmlDebugPacket.

Change-Id: I3f6ba73fcbfad5e8df917c5feb9308116738a614
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

1 files changed, 11 insertions, 20 deletions

diff --git a/src/plugins/qmltooling/packetprotocol/qpacketprotocol.cpp b/src/plugins/qmltooling/packetprotocol/qpacketprotocol.cpp
index 9f9dbfee90..d576e74e53 100644
--- a/src/plugins/qmltooling/packetprotocol/qpacketprotocol.cpp
+++ b/src/plugins/qmltooling/packetprotocol/qpacketprotocol.cpp
@@ -36,7 +36,6 @@
 #include <QtCore/QElapsedTimer>
 #include <private/qiodevice_p.h>
 #include <private/qobject_p.h>
-#include <private/qpacket_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -63,9 +62,8 @@ static const int MAX_PACKET_SIZE = 0x7FFFFFFF;
 
   QPacketProtocol does not perform any communications itself.  Instead it can
   operate on any QIODevice that supports the QIODevice::readyRead() signal.  A
-  logical "packet" is encapsulated by the companion QPacket class.  The
-  following example shows two ways to send data using QPacketProtocol.  The
-  transmitted data is equivalent in both.
+  logical "packet" is simply a QByteArray. The following example how to send
+  data using QPacketProtocol.
 
   \code
   QTcpSocket socket;
@@ -74,9 +72,9 @@ static const int MAX_PACKET_SIZE = 0x7FFFFFFF;
   QPacketProtocol protocol(&socket);
 
   // Send a packet
-  QPacket packet;
+  QDataStream packet;
   packet << "Hello world" << 123;
-  protocol.send(packet);
+  protocol.send(packet.data());
   \endcode
 
   Likewise, the following shows how to read data from QPacketProtocol, assuming
@@ -88,16 +86,12 @@ static const int MAX_PACKET_SIZE = 0x7FFFFFFF;
   int a;
   QByteArray b;
 
-  // Receive packet the quick way
-  protocol.read() >> a >> b;
-
-  // Receive packet the longer way
-  QPacket packet = protocol.read();
+  // Receive packet
+  QDataStream packet(protocol.read());
   p >> a >> b;
   \endcode
 
   \ingroup io
-  \sa QPacket
 */
 
 class QPacketProtocolPrivate : public QObjectPrivate
@@ -133,15 +127,14 @@ QPacketProtocol::QPacketProtocol(QIODevice *dev, QObject *parent)
 }
 
 /*!
-  \fn void QPacketProtocol::send(const QPacket & packet)
+  \fn void QPacketProtocol::send(const QByteArray &data)
 
   Transmit the \a packet.
  */
-void QPacketProtocol::send(const QPacket & p)
+void QPacketProtocol::send(const QByteArray &data)
 {
     Q_D(QPacketProtocol);
 
-    QByteArray data = p.data();
     if (data.isEmpty())
         return; // We don't send empty packets
     qint64 sendSize = data.size() + sizeof(qint32);
@@ -165,15 +158,13 @@ qint64 QPacketProtocol::packetsAvailable() const
 }
 
 /*!
-  Return the next unread packet, or an invalid QPacket instance if no packets
+  Return the next unread packet, or an empty QByteArray if no packets
   are available.  This method does NOT block.
   */
-QPacket QPacketProtocol::read()
+QByteArray QPacketProtocol::read()
 {
     Q_D(QPacketProtocol);
-
-    // Hope for in-place construction here, until we get move semantics for QBuffer
-    return QPacket(d->packets.isEmpty() ? QByteArray() : d->packets.takeFirst());
+    return d->packets.isEmpty() ? QByteArray() : d->packets.takeFirst();
 }
 
 /*!