QmlProfiler: Don't trust in externally provided timestamps

We might get timestamps that are outside the trace time, negative
timestamps, ranges that go backwards, and other insane things.

In order to deal with this, we clamp all negative timestamps to 0, and
treat the specified trace time as minimum range, that can be overridden
by events.

Change-Id: Iba661f2a4346077871fc62a46759e169b2aad49d
Reviewed-by: Milian Wolff <milian.wolff@kdab.com>

src/plugins/qmlprofiler/qmlprofilermodelmanager.cpp

@@ -92,18 +92,23 @@ bool QmlProfilerTraceTime::isRestrictedToRange() const
 void QmlProfilerTraceTime::clear()
 {
     restrictToRange(-1, -1);
-    setTime(-1, -1);
+    m_startTime = -1;
+    m_endTime = -1;
 }
 
-void QmlProfilerTraceTime::setTime(qint64 startTime, qint64 endTime)
+void QmlProfilerTraceTime::update(qint64 time)
 {
-    QTC_ASSERT(startTime <= endTime, endTime = startTime);
-    m_startTime = startTime;
-    m_endTime = endTime;
+    QTC_ASSERT(time >= 0, return);
+    if (m_startTime > time || m_startTime == -1)
+        m_startTime = time;
+    if (m_endTime < time || m_endTime == -1)
+        m_endTime = time;
+    QTC_ASSERT(m_endTime >= m_startTime, m_startTime = m_endTime);
 }
 
 void QmlProfilerTraceTime::decreaseStartTime(qint64 time)
 {
+    QTC_ASSERT(time >= 0, return);
     if (m_startTime > time || m_startTime == -1) {
         m_startTime = time;
         if (m_endTime == -1)
@@ -115,6 +120,7 @@ void QmlProfilerTraceTime::decreaseStartTime(qint64 time)
 
 void QmlProfilerTraceTime::increaseEndTime(qint64 time)
 {
+    QTC_ASSERT(time >= 0, return);
     if (m_endTime < time || m_endTime == -1) {
         m_endTime = time;
         if (m_startTime == -1)
@@ -244,6 +250,7 @@ void QmlProfilerModelManager::addEvents(const QVector<QmlEvent> &events)
 {
     for (const QmlEvent &event : events) {
         d->eventStream << event;
+        d->traceTime->update(event.timestamp());
         d->dispatch(event, d->eventTypes[event.typeIndex()]);
     }
 }
@@ -251,6 +258,7 @@ void QmlProfilerModelManager::addEvents(const QVector<QmlEvent> &events)
 void QmlProfilerModelManager::addEvent(const QmlEvent &event)
 {
     d->eventStream << event;
+    d->traceTime->update(event.timestamp());
     QTC_ASSERT(event.typeIndex() < d->eventTypes.size(),
                d->eventTypes.resize(event.typeIndex() + 1));
     d->dispatch(event, d->eventTypes.at(event.typeIndex()));
@@ -606,7 +614,10 @@ void QmlProfilerModelManager::load(const QString &filename)
             this, &QmlProfilerModelManager::addEvents);
 
     connect(reader, &QmlProfilerFileReader::success, this, [this, reader]() {
-        d->traceTime->setTime(reader->traceStart(), reader->traceEnd());
+        if (reader->traceStart() >= 0)
+            d->traceTime->decreaseStartTime(reader->traceStart());
+        if (reader->traceEnd() >= 0)
+            d->traceTime->increaseEndTime(reader->traceEnd());
         setRecordedFeatures(reader->loadedFeatures());
         delete reader;
         acquiringDone();

src/plugins/qmlprofiler/qmlprofilermodelmanager.h

@@ -58,7 +58,7 @@ public:
 
     void clear();
 
-    void setTime(qint64 startTime, qint64 endTime);
+    void update(qint64 time);
     void decreaseStartTime(qint64 time);
     void increaseEndTime(qint64 time);
     void restrictToRange(qint64 startTime, qint64 endTime);

src/plugins/qmlprofiler/qmlprofilertraceclient.cpp

@@ -247,7 +247,7 @@ void QmlProfilerTraceClient::setRequestedFeatures(quint64 features)
                        const QmlDebug::QDebugContextInfo &context)
         {
             d->updateFeatures(ProfileDebugMessages);
-            d->currentEvent.event.setTimestamp(context.timestamp);
+            d->currentEvent.event.setTimestamp(context.timestamp > 0 ? context.timestamp : 0);
             d->currentEvent.event.setTypeIndex(-1);
             d->currentEvent.event.setString(text);
             d->currentEvent.type = QmlEventType(DebugMessage, MaximumRangeType, type,

src/plugins/qmlprofiler/qmlprofilertracefile.cpp

@@ -257,6 +257,8 @@ void QmlProfilerFileReader::loadQzt(QIODevice *device)
                     return;
                 }
                 m_loadedFeatures |= (1ULL << m_eventTypes[event.typeIndex()].feature());
+                if (event.timestamp() < 0)
+                    event.setTimestamp(0);
             } else if (bufferStream.status() == QDataStream::ReadPastEnd) {
                 break; // Apparently EOF is a character so we end up here after the last event.
             } else if (bufferStream.status() == QDataStream::ReadCorruptData) {
@@ -506,15 +508,16 @@ void QmlProfilerFileReader::loadEvents(QXmlStreamReader &stream)
                     continue;
                 }
 
-                event.setTimestamp(attributes.value(_("startTime")).toLongLong());
+                const qint64 timestamp = attributes.value(_("startTime")).toLongLong();
+                event.setTimestamp(timestamp > 0 ? timestamp : 0);
                 event.setTypeIndex(attributes.value(_("eventIndex")).toInt());
 
                 if (attributes.hasAttribute(_("duration"))) {
                     event.setRangeStage(RangeStart);
                     QmlEvent rangeEnd(event);
                     rangeEnd.setRangeStage(RangeEnd);
-                    rangeEnd.setTimestamp(event.timestamp()
-                                          + attributes.value(_("duration")).toLongLong());
+                    const qint64 duration = attributes.value(_("duration")).toLongLong();
+                    rangeEnd.setTimestamp(event.timestamp() + (duration > 0 ? duration : 0));
                     events.addRange(event, rangeEnd);
                 } else {
                     // attributes for special events

src/plugins/qmlprofiler/qmltypedevent.cpp

@@ -44,7 +44,7 @@ QDataStream &operator>>(QDataStream &stream, QmlTypedEvent &event)
         subtype = -1;
     }
 
-    event.event.setTimestamp(time);
+    event.event.setTimestamp(time > 0 ? time : 0);
     event.event.setTypeIndex(-1);
     event.serverTypeId = 0;
 

src/plugins/qmlprofiler/tests/pixmapcachemodel_test.cpp

@@ -38,7 +38,8 @@ PixmapCacheModelTest::PixmapCacheModelTest(QObject *parent) : QObject(parent),
 void PixmapCacheModelTest::initTestCase()
 {
     manager.startAcquiring();
-    manager.traceTime()->setTime(1, 300);
+    manager.traceTime()->decreaseStartTime(1);
+    manager.traceTime()->increaseEndTime(300);
 
     for (int i = 0; i < MaximumPixmapEventType; ++i) {
         eventTypeIndices[i] = manager.numLoadedEventTypes();