Merge lp:~nick-dedekind/unity8/console-log into lp:unity8

[Nick Dedekind]

Debug tool for printing our the console log to a control.

Debug tool for printing our the console log to a control.

Enable/Disable shell overlay via debug dbus interface:
com.canonical.Unity8/com/canonical/Unity8/Debugging::SetLogOverlay

[lp:~nick-dedekind/unity8/console-log]

2537. By Nick Dedekind on 2016-07-08

added missing files

2538. By Nick Dedekind on 2016-07-08

fixed comment

2539. By Nick Dedekind on 2016-07-08

order

2540. By Nick Dedekind on 2016-07-08

use functional

2541. By Nick Dedekind on 2016-07-08

use qthread::sleep, close write fd + cleanup

[Unity8 CI Bot (unity8-ci-bot)]

FAILED: Continuous integration, rev:2537
https://unity8-jenkins.ubuntu.com/job/lp-unity8-ci/1696/
Executed test runs:
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build/2243/console
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-0-fetch/2271
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=vivid+overlay/2177
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial+overlay/2177
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=yakkety/2177
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=vivid+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=xenial+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=yakkety/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=vivid+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=xenial+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=yakkety/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=vivid+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=xenial+overlay/2168/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=yakkety/2168/console

Click here to trigger a rebuild:
https://unity8-jenkins.ubuntu.com/job/lp-unity8-ci/1696/rebuild

review: Needs Fixing (continuous-integration)

[Unity8 CI Bot (unity8-ci-bot)]

FAILED: Continuous integration, rev:2541
https://unity8-jenkins.ubuntu.com/job/lp-unity8-ci/1697/
Executed test runs:
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build/2244/console
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-0-fetch/2272
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=vivid+overlay/2178
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial+overlay/2178
    SUCCESS: https://unity8-jenkins.ubuntu.com/job/build-1-sourcepkg/release=yakkety/2178
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=vivid+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=xenial+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=amd64,release=yakkety/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=vivid+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=xenial+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=armhf,release=yakkety/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=vivid+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=xenial+overlay/2169/console
    FAILURE: https://unity8-jenkins.ubuntu.com/job/build-2-binpkg/arch=i386,release=yakkety/2169/console

Click here to trigger a rebuild:
https://unity8-jenkins.ubuntu.com/job/lp-unity8-ci/1697/rebuild

review: Needs Fixing (continuous-integration)

[Albert Astals Cid (aacid)]

Text conflict in tests/uqmlscene/CMakeLists.txt
1 conflicts encountered.

[Albert Astals Cid (aacid)]

More than a month with merge conflicts -> WiP

Unmerged revisions

2541. By Nick Dedekind on 2016-07-08

use qthread::sleep, close write fd + cleanup

2540. By Nick Dedekind on 2016-07-08

use functional

2539. By Nick Dedekind on 2016-07-08

order

2538. By Nick Dedekind on 2016-07-08

fixed comment

2537. By Nick Dedekind on 2016-07-08

added missing files

2536. By Nick Dedekind on 2016-07-08

connect to debug interface

2535. By Nick Dedekind on 2016-07-08

pulled parent

2534. By Nick Dedekind on 2016-07-08

merged fly debugging

2533. By Nick Dedekind on 2016-07-08

Added Unity.Debug

2532. By Nick Dedekind on 2016-07-07

added console log

=== modified file 'plugins/Unity/CMakeLists.txt'
--- plugins/Unity/CMakeLists.txt	2015-10-09 12:36:14 +0000
+++ plugins/Unity/CMakeLists.txt	2016-07-08 11:04:05 +0000
@@ -1,4 +1,5 @@
 add_subdirectory(Connectivity)
+add_subdirectory(Debug)
 add_subdirectory(Indicators)
 add_subdirectory(Launcher)
 add_subdirectory(Session)

=== added directory 'plugins/Unity/Debug'
=== added file 'plugins/Unity/Debug/CMakeLists.txt'
--- plugins/Unity/Debug/CMakeLists.txt	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/CMakeLists.txt	2016-07-08 11:04:05 +0000
@@ -0,0 +1,30 @@
+include_directories(
+    ${CMAKE_CURRENT_SOURCE_DIR}
+    ${CMAKE_CURRENT_BINARY_DIR}
+)
+
+include_directories(
+    SYSTEM
+    ${Qt5Gui_PRIVATE_INCLUDE_DIRS}
+    ${Qt5Quick_PRIVATE_INCLUDE_DIRS}
+    ${GIO_INCLUDE_DIRS}
+)
+
+set(QMLPLUGIN_SRC
+    consolelog.cpp
+    plugin.cpp
+    )
+
+add_library(Debug-qml SHARED
+    ${QMLPLUGIN_SRC}
+    )
+
+# Because this is an internal support library, we want
+# to expose all symbols in it. Consider changing this
+# either to a static library or just using the
+# files directly in targets.
+set_target_properties(Debug-qml PROPERTIES COMPILE_FLAGS -fvisibility=default)
+
+qt5_use_modules(Debug-qml Qml Quick Concurrent)
+
+add_unity8_plugin(Unity.Debug 0.1 Unity/Debug TARGETS Debug-qml)

=== added file 'plugins/Unity/Debug/consolelog.cpp'
--- plugins/Unity/Debug/consolelog.cpp	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/consolelog.cpp	2016-07-08 11:04:05 +0000
@@ -0,0 +1,221 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "consolelog.h"
+
+#include <unistd.h>
+#include <stdio.h>
+#include <thread>
+#include <iostream>
+#include <sys/ioctl.h>
+
+#include <functional>
+
+namespace
+{
+
+int wait_fd(std::function<int(void)> fn)
+{
+    int ret = -1;
+    bool fd_blocked = false;
+    do
+    {
+         ret = fn();
+         fd_blocked = (errno == EINTR ||  errno == EBUSY);
+         if (fd_blocked)
+            QThread::msleep(10);
+    }
+    while (ret < 0);
+    return ret;
+}
+
+#define PIPE_WAIT(val) wait_fd(std::bind(pipe, val))
+#define DUP_WAIT(fd) wait_fd(std::bind(dup, fd))
+#define DUP2_WAIT(fd1, fd2) wait_fd(std::bind(dup2, fd1, fd2))
+#define CLOSE_WAIT(fd) wait_fd(std::bind(close, fd))
+
+}
+
+LogRedirector::LogRedirector()
+    : m_ref(0)
+    , m_stop(false)
+{
+    setObjectName("ConsoleLog");
+
+    // make stdout & stderr streams unbuffered
+    // so that we don't need to flush the streams
+    // before capture and after capture
+    // (fflush can cause a deadlock if the stream is currently being used)
+    setvbuf(stdout,NULL,_IONBF,0);
+    setvbuf(stderr,NULL,_IONBF,0);
+}
+
+void LogRedirector::run()
+{
+    PIPE_WAIT(m_pipe);
+
+    int oldStdOut = DUP_WAIT(fileno(stdout));
+    int oldStdErr = DUP_WAIT(fileno(stderr));
+
+    DUP2_WAIT(m_pipe[WRITE], fileno(stdout));
+    DUP2_WAIT(m_pipe[WRITE], fileno(stderr));
+    CLOSE_WAIT(m_pipe[WRITE]);
+
+    while(true) {
+        {
+            QMutexLocker lock(&m_mutex);
+            if (m_stop) break;
+        }
+        checkLog();
+        QThread::msleep(50);
+    }
+
+    DUP2_WAIT(oldStdOut, fileno(stdout));
+    DUP2_WAIT(oldStdErr, fileno(stderr));
+
+    CLOSE_WAIT(oldStdOut);
+    CLOSE_WAIT(oldStdErr);
+    CLOSE_WAIT(m_pipe[READ]);
+}
+
+
+void LogRedirector::checkLog()
+{
+    // Do not allow read to block with no data.
+    // If we stop the thread while waiting a read,
+    // it will block the main thread waiting for this thread to stop.
+    int count = 0;
+    ioctl(m_pipe[READ], FIONREAD, &count);
+    if (count <= 0) return;
+
+    std::string captured;
+    std::string buf;
+    const int bufSize = 1024;
+    buf.resize(bufSize);
+    int bytesRead = 0;
+    bytesRead = read(m_pipe[READ], &(*buf.begin()), bufSize);
+    while(bytesRead == bufSize)
+    {
+        captured += buf;
+        bytesRead = 0;
+        bytesRead = read(m_pipe[READ], &(*buf.begin()), bufSize);
+    }
+    if (bytesRead > 0)
+    {
+        buf.resize(bytesRead);
+        captured += buf;
+    }
+
+    if (!captured.empty()) {
+        Q_EMIT log(QString::fromStdString(captured));
+    }
+}
+
+LogRedirector *LogRedirector::instance()
+{
+    static LogRedirector* log = nullptr;
+    if (!log) {
+        log = new LogRedirector();
+    }
+    return log;
+}
+
+void LogRedirector::add(ConsoleLog* logger)
+{
+    QMutexLocker lock(&m_mutex);
+    connect(this, &LogRedirector::log, logger, &ConsoleLog::logged, Qt::UniqueConnection);
+
+    m_ref++;
+    if (!LogRedirector::instance()->isRunning()) {
+        m_stop = false;
+        LogRedirector::instance()->start();
+    }
+}
+
+void LogRedirector::remove(ConsoleLog* logger)
+{
+    QMutexLocker lock(&m_mutex);
+    disconnect(this, &LogRedirector::log, logger, &ConsoleLog::logged);
+
+    m_ref = qMax(m_ref-1, 0);
+    if (m_ref == 0 && LogRedirector::instance()->isRunning()) {
+        m_stop = true;
+        lock.unlock();
+        LogRedirector::instance()->wait();
+    }
+}
+
+ConsoleLog::ConsoleLog(QObject *parent)
+    : QObject(parent)
+    , m_enabled(false)
+    , m_maxLines(60)
+{
+    auto updateEnabled = [this]() {
+        if (m_enabled) {
+            LogRedirector::instance()->add(this);
+        } else {
+            LogRedirector::instance()->remove(this);
+        }
+    };
+    connect(this, &ConsoleLog::enabledChanged, this, updateEnabled);
+}
+
+ConsoleLog::~ConsoleLog()
+{
+    if (m_enabled) {
+        LogRedirector::instance()->remove(this);
+    }
+}
+
+void ConsoleLog::setEnabled(bool enabled)
+{
+    if (m_enabled == enabled) {
+        return;
+    }
+
+    m_enabled = enabled;
+    Q_EMIT enabledChanged();
+}
+
+QString ConsoleLog::out() const
+{
+    return m_out.join("\n");
+}
+
+void ConsoleLog::setMaxLines(int maxLines)
+{
+    if (m_maxLines == maxLines) {
+        return;
+    }
+
+    m_maxLines = maxLines;
+    while (m_out.count() > m_maxLines) {
+        m_out.removeLast();
+    }
+    Q_EMIT outChanged();
+    Q_EMIT maxLinesChanged();
+}
+
+void ConsoleLog::logged(QString captured)
+{
+    QStringList li = captured.split("\n", QString::SkipEmptyParts);
+    li << m_out;
+    m_out = li;
+    while (m_out.count() > m_maxLines) {
+        m_out.removeLast();
+    }
+    Q_EMIT outChanged();
+}

=== added file 'plugins/Unity/Debug/consolelog.h'
--- plugins/Unity/Debug/consolelog.h	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/consolelog.h	2016-07-08 11:04:05 +0000
@@ -0,0 +1,87 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef CONSOLELOG_H
+#define CONSOLELOG_H
+
+#include <QThread>
+#include <QMutex>
+#include <QSet>
+
+class ConsoleLog;
+
+class LogRedirector : public QThread
+{
+    Q_OBJECT
+public:
+    static LogRedirector *instance();
+
+    void add(ConsoleLog* logger);
+    void remove(ConsoleLog* logger);
+
+private Q_SLOTS:
+    void checkLog();
+
+Q_SIGNALS:
+    void log(QString log);
+
+private:
+    LogRedirector();
+    void run() Q_DECL_OVERRIDE;
+
+    QMutex m_mutex;
+    int m_pipe[2];
+    int m_ref;
+    bool m_stop;
+
+    enum PIPES { READ, WRITE };
+};
+
+class ConsoleLog : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(bool enabled READ isEnabled WRITE setEnabled NOTIFY enabledChanged)
+    Q_PROPERTY(QString out READ out NOTIFY outChanged)
+    Q_PROPERTY(int maxLines READ maxLines WRITE setMaxLines NOTIFY maxLinesChanged)
+public:
+    explicit ConsoleLog(QObject *parent = 0);
+    ~ConsoleLog();
+
+    bool isEnabled() const { return m_enabled; }
+    void setEnabled(bool enabled);
+
+    QString out() const;
+
+    int maxLines() const { return m_maxLines; }
+    void setMaxLines(int maxLines);
+
+public Q_SLOTS:
+    void logged(QString captured);
+
+Q_SIGNALS:
+    void enabledChanged();
+    void outChanged();
+    void maxLinesChanged();
+
+private:
+    void updateEnabled();
+
+    QStringList m_out;
+    bool m_enabled;
+    int m_maxLines;
+};
+
+#endif // CONSOLELOG_H

=== added file 'plugins/Unity/Debug/plugin.cpp'
--- plugins/Unity/Debug/plugin.cpp	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/plugin.cpp	2016-07-08 11:04:05 +0000
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2016 Canonical, Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+// Qt
+#include <QtQml/qqml.h>
+
+// self
+#include "plugin.h"
+
+// local
+#include "consolelog.h"
+
+void UnityDebugPlugin::registerTypes(const char *uri)
+{
+    Q_ASSERT(uri == QLatin1String("Unity.Debug"));
+
+    qmlRegisterType<ConsoleLog>(uri, 0, 1, "ConsoleLog");
+}

=== added file 'plugins/Unity/Debug/plugin.h'
--- plugins/Unity/Debug/plugin.h	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/plugin.h	2016-07-08 11:04:05 +0000
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2016 Canonical, Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef UNITYDEBUG_PLUGIN_H
+#define UNITYDEBUG_PLUGIN_H
+
+#include <QtQml/QQmlEngine>
+#include <QtQml/QQmlExtensionPlugin>
+
+class UnityDebugPlugin : public QQmlExtensionPlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QQmlExtensionInterface")
+
+public:
+    void registerTypes(const char *uri) override;
+};
+
+#endif

=== added file 'plugins/Unity/Debug/qmldir'
--- plugins/Unity/Debug/qmldir	1970-01-01 00:00:00 +0000
+++ plugins/Unity/Debug/qmldir	2016-07-08 11:04:05 +0000
@@ -0,0 +1,3 @@
+module Unity.Debug
+plugin Debug-qml
+typeinfo Debug.qmltypes

=== modified file 'qml/Shell.qml'
--- qml/Shell.qml	2016-07-05 09:57:08 +0000
+++ qml/Shell.qml	2016-07-08 11:04:05 +0000
@@ -43,6 +43,7 @@
 import Unity.Indicators 0.1 as Indicators
 import Cursor 1.1
 import WindowManager 0.1
+import Unity.Debug 0.1 as Debug
 
 
 StyledItem {
@@ -809,4 +810,20 @@
             }
         }
     }
+
+    Loader {
+        z: shutdownFadeOutRectangle.z + 1
+        active: DebuggingController.logOverlay
+
+        sourceComponent: Text {
+            width: shell.width
+            height: shell.height
+
+            text: consoleLog.out
+            Debug.ConsoleLog {
+                id: consoleLog
+                enabled: true
+            }
+        }
+    }
 }

=== modified file 'src/DebuggingController.cpp'
--- src/DebuggingController.cpp	2016-07-08 11:04:05 +0000
+++ src/DebuggingController.cpp	2016-07-08 11:04:05 +0000
@@ -25,8 +25,9 @@
 #include <private/qquickitem_p.h>
 #include <private/qsgrenderer_p.h>
 
-DebuggingController::DebuggingController(QObject *parent):
-    UnityDBusObject(QStringLiteral("/com/canonical/Unity8/Debugging"), QStringLiteral("com.canonical.Unity8"), true, parent)
+DebuggingController::DebuggingController(QObject *parent)
+    : UnityDBusObject(QStringLiteral("/com/canonical/Unity8/Debugging"), QStringLiteral("com.canonical.Unity8"), true, parent)
+    , m_logOverlay(false)
 {
 }
 
@@ -67,3 +68,13 @@
 {
     QLoggingCategory::setFilterRules(filterRules);
 }
+
+void DebuggingController::SetLogOverlay(bool logOverlay)
+{
+    if (logOverlay == m_logOverlay) {
+        return;
+    }
+
+    m_logOverlay = logOverlay;
+    Q_EMIT logOverlayChanged(m_logOverlay);
+}

=== modified file 'src/DebuggingController.h'
--- src/DebuggingController.h	2016-07-08 11:04:05 +0000
+++ src/DebuggingController.h	2016-07-08 11:04:05 +0000
@@ -30,10 +30,14 @@
     Q_OBJECT
     Q_CLASSINFO("D-Bus Interface", "com.canonical.Unity8.Debugging")
 
+    Q_PROPERTY(bool logOverlay READ logOverlay NOTIFY logOverlayChanged)
+
 public:
     DebuggingController(QObject *parent = nullptr);
     ~DebuggingController() = default;
 
+    bool logOverlay() const { return m_logOverlay; }
+
 public Q_SLOTS:
     /**
       * Set the QSG_VISUALIZE mode. This follows the vlues supported by Qt in
@@ -50,5 +54,16 @@
       * Set the QLoggingCategory filter rules.
       */
     Q_SCRIPTABLE void SetLoggingFilterRules(const QString &filterRules);
+
+    /**
+      * Enable/Disable the shell console log overlay
+      */
+    Q_SCRIPTABLE void SetLogOverlay(bool logOverlay);
+
+Q_SIGNALS:
+    void logOverlayChanged(bool logOverlay);
+
+private:
+    bool m_logOverlay;
 };
 #endif // DEBUGGINGCONTROLLER_H

=== modified file 'src/ShellApplication.cpp'
--- src/ShellApplication.cpp	2016-07-08 11:04:05 +0000
+++ src/ShellApplication.cpp	2016-07-08 11:04:05 +0000
@@ -19,6 +19,7 @@
 // Qt
 #include <QLibrary>
 #include <QScreen>
+#include <QQmlContext>
 
 #include <libintl.h>
 
@@ -94,7 +95,7 @@
     }
     #endif
 
-    new DebuggingController(this);
+    m_qmlEngine->rootContext()->setContextProperty("DebuggingController", new DebuggingController(this));
 
     // Some hard-coded policy for now.
     // NB: We don't support more than two screens at the moment

=== modified file 'tests/uqmlscene/main.cpp'
--- tests/uqmlscene/main.cpp	2016-07-08 11:04:05 +0000
+++ tests/uqmlscene/main.cpp	2016-07-08 11:04:05 +0000
@@ -468,8 +468,6 @@
 
     int exitCode = 0;
 
-    new DebuggingController(&app);
-
     if (!options.file.isEmpty()) {
         if (!options.versionDetection || checkVersion(options.file)) {
 #ifndef QT_NO_TRANSLATION
@@ -479,6 +477,8 @@
             // TODO: as soon as the engine construction completes, the debug service is
             // listening for connections.  But actually we aren't ready to debug anything.
             QQmlEngine engine;
+            engine.rootContext()->setContextProperty("DebuggingController", new DebuggingController(&app));
+
             QQmlComponent *component = new QQmlComponent(&engine);
             for (int i = 0; i < imports.size(); ++i)
                 engine.addImportPath(imports.at(i));