[Performous-commit] Tapio Vierros : Fix analyzer thread causing crashing by implementing cancel mechanism.

[Tapio V. <aa...@us...>]

Module: editor
Branch: master
Commit: 45b23754e3f423813a5928a861b03fa3be291736

Author: Tapio Vierros <tap...@gm...>
Date:   Thu Jan 20 12:44:40 2011 +0200

Fix analyzer thread causing crashing by implementing cancel mechanism.

---

 pitchvis.cc |    4 ++++
 pitchvis.hh |    3 +++
 2 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/pitchvis.cc b/pitchvis.cc
index e1c44ef..61cfc97 100644
--- a/pitchvis.cc
+++ b/pitchvis.cc
@@ -51,6 +51,8 @@ void PitchVis::run()
 	}
 
 	for (unsigned x = 0; x < width; ++x) {
+		if (cancelled) return;
+
 		// Get decoded samples from ffmpeg
 		std::vector<float> data(step*2);
 		mpeg.audioQueue(&*data.begin(), &*data.end(), x * step * 2);
@@ -60,6 +62,7 @@ void PitchVis::run()
 		da::step_iterator<float> endIt(&*data.end(), 2);
 
 		// Analyze
+		if (cancelled) return;
 		analyzer.input(beginIt, endIt);
 		analyzer.process();
 
@@ -93,6 +96,7 @@ void PitchVis::run()
 
 		// Draw
 		{
+			if (cancelled) return;
 			QMutexLocker locker(&mutex);
 			unsigned* rgba = reinterpret_cast<unsigned*>(image.bits());
 			for (unsigned y = 0; y < height; ++y) {
diff --git a/pitchvis.hh b/pitchvis.hh
index 8cb3500..21ae0ca 100644
--- a/pitchvis.hh
+++ b/pitchvis.hh
@@ -40,13 +40,16 @@ class PitchVis: public QWidget, public QThread {
 	QString fileName;
 	QImage image;
 	bool moreAvailable;
+	bool cancelled;
 	QMutex mutex;
 public:
 	const std::size_t height;
 
 	PitchVis(QString const& filename, QWidget *parent = NULL);
+	~PitchVis() { stop(); wait(); }
 
 	void run(); // Thread runs here
+	void stop() { cancelled = true; }
 
 	QImage getImage() { QMutexLocker locker(&mutex); moreAvailable = false; return image; }
 	bool newDataAvailable() const { return moreAvailable; }