QmlDebug: Move EngineControl client to qmldebug

Change-Id: Ia2e01b3acb8e0dab19b67dd612e6228d13b4755d
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

4 files changed, 315 insertions, 0 deletions

diff --git a/src/qmldebug/qmldebug.pro b/src/qmldebug/qmldebug.pro
index 295701eee3..e5f6de3314 100644
--- a/src/qmldebug/qmldebug.pro
+++ b/src/qmldebug/qmldebug.pro
@@ -7,12 +7,15 @@ load(qt_module)
 SOURCES += \
     qqmldebugclient.cpp \
     qqmldebugconnection.cpp \
+    qqmlenginecontrolclient.cpp \
     qqmlprofilerclient.cpp
 
 HEADERS += \
     qqmldebugclient_p.h \
     qqmldebugclient_p_p.h \
     qqmldebugconnection_p.h \
+    qqmlenginecontrolclient_p.h \
+    qqmlenginecontrolclient_p_p.h \
     qqmleventlocation_p.h \
     qqmlprofilerclient_p.h \
     qqmlprofilerclient_p_p.h
diff --git a/src/qmldebug/qqmlenginecontrolclient.cpp b/src/qmldebug/qqmlenginecontrolclient.cpp
new file mode 100644
index 0000000000..b45e4e1f14
--- /dev/null
+++ b/src/qmldebug/qqmlenginecontrolclient.cpp
@@ -0,0 +1,147 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qqmlenginecontrolclient_p.h"
+#include "qqmlenginecontrolclient_p_p.h"
+#include "qqmldebugconnection_p.h"
+
+#include <private/qqmldebugserviceinterfaces_p.h>
+#include <private/qpacket_p.h>
+
+QT_BEGIN_NAMESPACE
+
+QQmlEngineControlClient::QQmlEngineControlClient(QQmlDebugConnection *connection) :
+    QQmlDebugClient(*(new QQmlEngineControlClientPrivate(connection)))
+{
+}
+
+QQmlEngineControlClient::QQmlEngineControlClient(QQmlEngineControlClientPrivate &dd) :
+    QQmlDebugClient(dd)
+{
+}
+
+/*!
+ * Block the starting or stopping of the engine with id \a engineId for now. By calling
+ * releaseEngine later the block can be lifted again. In the debugged application the engine control
+ * server waits until a message is received before continuing. So by not sending a message here we
+ * delay the process. Blocks add up. You have to call releaseEngine() as often as you've called
+ * blockEngine before. The intention of that is to allow different debug clients to use the same
+ * engine control and communicate with their respective counterparts before the QML engine starts or
+ * shuts down.
+ */
+void QQmlEngineControlClient::blockEngine(int engineId)
+{
+    Q_D(QQmlEngineControlClient);
+    Q_ASSERT(d->blockedEngines.contains(engineId));
+    d->blockedEngines[engineId].blockers++;
+}
+
+/*!
+ * Release the engine with id \a engineId. If no other blocks are present, depending on what the
+ * engine is waiting for, the start or stop command is sent to the process being debugged.
+ */
+void QQmlEngineControlClient::releaseEngine(int engineId)
+{
+    Q_D(QQmlEngineControlClient);
+    Q_ASSERT(d->blockedEngines.contains(engineId));
+
+    QQmlEngineControlClientPrivate::EngineState &state = d->blockedEngines[engineId];
+    if (--state.blockers == 0) {
+        Q_ASSERT(state.releaseCommand != QQmlEngineControlClientPrivate::InvalidCommand);
+        d->sendCommand(state.releaseCommand, engineId);
+        d->blockedEngines.remove(engineId);
+    }
+}
+
+QList<int> QQmlEngineControlClient::blockedEngines() const
+{
+    Q_D(const QQmlEngineControlClient);
+    return d->blockedEngines.keys();
+}
+
+void QQmlEngineControlClient::messageReceived(const QByteArray &data)
+{
+    Q_D(QQmlEngineControlClient);
+    QPacket stream(d->connection->currentDataStreamVersion(), data);
+    int message;
+    int id;
+    QString name;
+
+    stream >> message >> id;
+
+    if (!stream.atEnd())
+        stream >> name;
+
+    QQmlEngineControlClientPrivate::EngineState &state = d->blockedEngines[id];
+    Q_ASSERT(state.blockers == 0);
+    Q_ASSERT(state.releaseCommand == QQmlEngineControlClientPrivate::InvalidCommand);
+
+    switch (message) {
+    case QQmlEngineControlClientPrivate::EngineAboutToBeAdded:
+        state.releaseCommand = QQmlEngineControlClientPrivate::StartWaitingEngine;
+        emit engineAboutToBeAdded(id, name);
+        break;
+    case QQmlEngineControlClientPrivate::EngineAdded:
+        emit engineAdded(id, name);
+        break;
+    case QQmlEngineControlClientPrivate::EngineAboutToBeRemoved:
+        state.releaseCommand = QQmlEngineControlClientPrivate::StopWaitingEngine;
+        emit engineAboutToBeRemoved(id, name);
+        break;
+    case QQmlEngineControlClientPrivate::EngineRemoved:
+        emit engineRemoved(id, name);
+        break;
+    }
+
+    if (state.blockers == 0 &&
+            state.releaseCommand != QQmlEngineControlClientPrivate::InvalidCommand) {
+        d->sendCommand(state.releaseCommand, id);
+        d->blockedEngines.remove(id);
+    }
+}
+
+QQmlEngineControlClientPrivate::QQmlEngineControlClientPrivate(QQmlDebugConnection *connection) :
+    QQmlDebugClientPrivate(QQmlEngineControlService::s_key, connection)
+{
+}
+
+void QQmlEngineControlClientPrivate::sendCommand(
+        QQmlEngineControlClientPrivate::CommandType command, int engineId)
+{
+    Q_Q(QQmlEngineControlClient);
+    QPacket stream(connection->currentDataStreamVersion());
+    stream << int(command) << engineId;
+    q->sendMessage(stream.data());
+}
+
+QT_END_NAMESPACE
diff --git a/src/qmldebug/qqmlenginecontrolclient_p.h b/src/qmldebug/qqmlenginecontrolclient_p.h
new file mode 100644
index 0000000000..601f8a871d
--- /dev/null
+++ b/src/qmldebug/qqmlenginecontrolclient_p.h
@@ -0,0 +1,80 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLENGINECONTROLCLIENT_P_H
+#define QQMLENGINECONTROLCLIENT_P_H
+
+#include "qqmldebugclient_p.h"
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+class QQmlEngineControlClientPrivate;
+class QQmlEngineControlClient : public QQmlDebugClient
+{
+    Q_OBJECT
+    Q_DECLARE_PRIVATE(QQmlEngineControlClient)
+public:
+    QQmlEngineControlClient(QQmlDebugConnection *connection);
+
+    void blockEngine(int engineId);
+    void releaseEngine(int engineId);
+
+    QList<int> blockedEngines() const;
+
+signals:
+    void engineAboutToBeAdded(int engineId, const QString &name);
+    void engineAdded(int engineId, const QString &name);
+    void engineAboutToBeRemoved(int engineId, const QString &name);
+    void engineRemoved(int engineId, const QString &name);
+
+protected:
+    QQmlEngineControlClient(QQmlEngineControlClientPrivate &dd);
+
+private:
+    void messageReceived(const QByteArray &);
+};
+
+QT_END_NAMESPACE
+
+#endif // QQMLENGINECONTROLCLIENT_P_H
diff --git a/src/qmldebug/qqmlenginecontrolclient_p_p.h b/src/qmldebug/qqmlenginecontrolclient_p_p.h
new file mode 100644
index 0000000000..7e99c35948
--- /dev/null
+++ b/src/qmldebug/qqmlenginecontrolclient_p_p.h
@@ -0,0 +1,85 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLENGINECONTROLCLIENT_P_P_H
+#define QQMLENGINECONTROLCLIENT_P_P_H
+
+#include "qqmlenginecontrolclient_p.h"
+#include "qqmldebugclient_p_p.h"
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+class QQmlEngineControlClientPrivate : public QQmlDebugClientPrivate
+{
+    Q_DECLARE_PUBLIC(QQmlEngineControlClient)
+public:
+    enum MessageType {
+        EngineAboutToBeAdded,
+        EngineAdded,
+        EngineAboutToBeRemoved,
+        EngineRemoved
+    };
+
+    enum CommandType {
+        StartWaitingEngine,
+        StopWaitingEngine,
+        InvalidCommand
+    };
+
+    QQmlEngineControlClientPrivate(QQmlDebugConnection *connection);
+
+    void sendCommand(CommandType command, int engineId);
+
+    struct EngineState {
+        EngineState(CommandType command = InvalidCommand) : releaseCommand(command), blockers(0) {}
+        CommandType releaseCommand;
+        int blockers;
+    };
+
+    QHash<int, EngineState> blockedEngines;
+};
+
+QT_END_NAMESPACE
+
+#endif // QQMLENGINECONTROLCLIENT_P_P_H