From: Soeren Apel <redacted>
Date: Wed, 22 Aug 2018 07:33:48 +0000 (+0200)
Subject: Implement decode pausing/resuming
X-Git-Url: https://sigrok.org/gitweb/?p=pulseview.git;a=commitdiff_plain;h=556259d2d0a212c20db9b18311b9524b52401a56

Implement decode pausing/resuming
---

diff --git a/icons/media-playback-pause.png b/icons/media-playback-pause.png
new file mode 100644
index 00000000..ee40fc26
Binary files /dev/null and b/icons/media-playback-pause.png differ
diff --git a/icons/media-playback-start.png b/icons/media-playback-start.png
new file mode 100644
index 00000000..10102d82
Binary files /dev/null and b/icons/media-playback-start.png differ
diff --git a/pv/data/decodesignal.cpp b/pv/data/decodesignal.cpp
index 05dc3428..4705b104 100644
--- a/pv/data/decodesignal.cpp
+++ b/pv/data/decodesignal.cpp
@@ -151,6 +151,9 @@ void DecodeSignal::reset_decode(bool shutting_down)
 		logic_mux_thread_.join();
 	}
 
+	decode_pause_mutex_.unlock();
+	decode_paused_ = false;
+
 	class_rows_.clear();
 	current_segment_id_ = 0;
 	segments_.clear();
@@ -258,6 +261,25 @@ void DecodeSignal::begin_decode()
 	decode_thread_ = std::thread(&DecodeSignal::decode_proc, this);
 }
 
+void DecodeSignal::pause_decode()
+{
+	decode_paused_ = true;
+}
+
+void DecodeSignal::resume_decode()
+{
+	// Manual unlocking is done before notifying, to avoid waking up the
+	// waiting thread only to block again (see notify_one for details)
+	decode_pause_mutex_.unlock();
+	decode_pause_cond_.notify_one();
+	decode_paused_ = false;
+}
+
+bool DecodeSignal::is_paused() const
+{
+	return decode_paused_;
+}
+
 QString DecodeSignal::error_message() const
 {
 	lock_guard<mutex> lock(output_mutex_);
@@ -981,6 +1003,11 @@ void DecodeSignal::decode_data(
 		// Notify the frontend that we processed some data and
 		// possibly have new annotations as well
 		new_annotations();
+
+		if (decode_paused_) {
+			unique_lock<mutex> pause_wait_lock(decode_pause_mutex_);
+			decode_pause_cond_.wait(pause_wait_lock);
+		}
 	}
 }
 
diff --git a/pv/data/decodesignal.hpp b/pv/data/decodesignal.hpp
index f00a9f1c..ba9c9b5e 100644
--- a/pv/data/decodesignal.hpp
+++ b/pv/data/decodesignal.hpp
@@ -101,6 +101,9 @@ public:
 
 	void reset_decode(bool shutting_down = false);
 	void begin_decode();
+	void pause_decode();
+	void resume_decode();
+	bool is_paused() const;
 	QString error_message() const;
 
 	const vector<data::DecodeChannel> get_channels() const;
@@ -215,12 +218,15 @@ private:
 	vector<DecodeSegment> segments_;
 	uint32_t current_segment_id_;
 
-	mutable mutex input_mutex_, output_mutex_, logic_mux_mutex_;
-	mutable condition_variable decode_input_cond_, logic_mux_cond_;
+	mutable mutex input_mutex_, output_mutex_, decode_pause_mutex_, logic_mux_mutex_;
+	mutable condition_variable decode_input_cond_, decode_pause_cond_,
+		logic_mux_cond_;
 
 	std::thread decode_thread_, logic_mux_thread_;
 	atomic<bool> decode_interrupt_, logic_mux_interrupt_;
 
+	bool decode_paused_;
+
 	QString error_message_;
 };
 
diff --git a/pv/views/trace/decodetrace.cpp b/pv/views/trace/decodetrace.cpp
index 651b8c3d..574e9d1a 100644
--- a/pv/views/trace/decodetrace.cpp
+++ b/pv/views/trace/decodetrace.cpp
@@ -341,15 +341,33 @@ QMenu* DecodeTrace::create_view_context_menu(QWidget *parent, QPoint &click_pos)
 
 	QMenu *const menu = new QMenu(parent);
 
+	if (decode_signal_->is_paused()) {
+		QAction *const resume =
+			new QAction(tr("Resume decoding"), this);
+		resume->setIcon(QIcon::fromTheme("media-playback-start",
+			QIcon(":/icons/media-playback-start.png")));
+		connect(resume, SIGNAL(triggered()), this, SLOT(on_pause_decode()));
+		menu->addAction(resume);
+	} else {
+		QAction *const pause =
+			new QAction(tr("Pause decoding"), this);
+		pause->setIcon(QIcon::fromTheme("media-playback-pause",
+			QIcon(":/icons/media-playback-pause.png")));
+		connect(pause, SIGNAL(triggered()), this, SLOT(on_pause_decode()));
+		menu->addAction(pause);
+	}
+
+	menu->addSeparator();
+
 	QAction *const export_all_rows =
-			new QAction(tr("Export all annotations"), this);
+		new QAction(tr("Export all annotations"), this);
 	export_all_rows->setIcon(QIcon::fromTheme("document-save-as",
 		QIcon(":/icons/document-save-as.png")));
 	connect(export_all_rows, SIGNAL(triggered()), this, SLOT(on_export_all_rows()));
 	menu->addAction(export_all_rows);
 
 	QAction *const export_row =
-			new QAction(tr("Export all annotations for this row"), this);
+		new QAction(tr("Export all annotations for this row"), this);
 	export_row->setIcon(QIcon::fromTheme("document-save-as",
 		QIcon(":/icons/document-save-as.png")));
 	connect(export_row, SIGNAL(triggered()), this, SLOT(on_export_row()));
@@ -1037,6 +1055,14 @@ void DecodeTrace::on_decode_finished()
 		owner_->row_item_appearance_changed(false, true);
 }
 
+void DecodeTrace::on_pause_decode()
+{
+	if (decode_signal_->is_paused())
+		decode_signal_->resume_decode();
+	else
+		decode_signal_->pause_decode();
+}
+
 void DecodeTrace::delete_pressed()
 {
 	on_delete();
diff --git a/pv/views/trace/decodetrace.hpp b/pv/views/trace/decodetrace.hpp
index 9372f7af..57e46220 100644
--- a/pv/views/trace/decodetrace.hpp
+++ b/pv/views/trace/decodetrace.hpp
@@ -187,6 +187,7 @@ private Q_SLOTS:
 	void on_delayed_trace_update();
 	void on_decode_reset();
 	void on_decode_finished();
+	void on_pause_decode();
 
 	void on_delete();