From 5b7cf66c34d7beeef055b06b95d72f9d7a3de680 Mon Sep 17 00:00:00 2001
From: Joel Holdsworth <joel@airwebreathe.org.uk>
Date: Sun, 2 Dec 2012 16:25:13 +0000
Subject: [PATCH] Added proof of concept start/stop support

---
 pv/mainwindow.cpp | 16 ++++++++++++----
 pv/sigsession.cpp | 36 ++++++++++++++++++++++++++++++++----
 pv/sigsession.h   | 13 +++++++++++++
 3 files changed, 57 insertions(+), 8 deletions(-)

diff --git a/pv/mainwindow.cpp b/pv/mainwindow.cpp
index c8c091d8..f1493667 100644
--- a/pv/mainwindow.cpp
+++ b/pv/mainwindow.cpp
@@ -184,10 +184,18 @@ void MainWindow::on_actionAbout_triggered()
 
 void MainWindow::run_stop()
 {
-	_session.start_capture(
-		_sampling_bar->get_selected_device(),
-		_sampling_bar->get_record_length(),
-		_sampling_bar->get_sample_rate());
+	switch(_session.get_capture_state()) {
+	case SigSession::Stopped:
+		_session.start_capture(
+			_sampling_bar->get_selected_device(),
+			_sampling_bar->get_record_length(),
+			_sampling_bar->get_sample_rate());
+		break;
+
+	case SigSession::Running:
+		_session.stop_capture();
+		break;
+	}
 }
 
 } // namespace pv
diff --git a/pv/sigsession.cpp b/pv/sigsession.cpp
index abe9b2da..580b6796 100644
--- a/pv/sigsession.cpp
+++ b/pv/sigsession.cpp
@@ -36,7 +36,8 @@ namespace pv {
 // TODO: This should not be necessary
 SigSession* SigSession::_session = NULL;
 
-SigSession::SigSession()
+SigSession::SigSession() :
+	_capture_state(Stopped)
 {
 	// TODO: This should not be necessary
 	_session = this;
@@ -44,6 +45,8 @@ SigSession::SigSession()
 
 SigSession::~SigSession()
 {
+	stop_capture();
+
 	if(_sampling_thread.get())
 		_sampling_thread->join();
 	_sampling_thread.reset();
@@ -63,18 +66,38 @@ void SigSession::load_file(const std::string &name)
 	}
 }
 
+SigSession::capture_state SigSession::get_capture_state() const
+{
+	lock_guard<mutex> lock(_state_mutex);
+	return _capture_state;
+}
+
 void SigSession::start_capture(struct sr_dev_inst *sdi,
 	uint64_t record_length, uint64_t sample_rate)
 {
-	// Check sampling isn't already active
-	if(_sampling_thread.get())
-		_sampling_thread->join();
+	stop_capture();
+
 
 	_sampling_thread.reset(new boost::thread(
 		&SigSession::sample_thread_proc, this, sdi,
 		record_length, sample_rate));
 }
 
+void SigSession::stop_capture()
+{
+	if(get_capture_state() == Stopped)
+		return;
+
+	sr_session_stop();
+
+	// Check that sampling stopped
+	if(_sampling_thread.get())
+		_sampling_thread->join();
+	_sampling_thread.reset();
+
+	_capture_state = Stopped;
+}
+
 vector< shared_ptr<view::Signal> > SigSession::get_signals()
 {
 	lock_guard<mutex> lock(_signals_mutex);
@@ -117,6 +140,11 @@ void SigSession::sample_thread_proc(struct sr_dev_inst *sdi,
 		return;
 	}
 
+	{
+		lock_guard<mutex> lock(_state_mutex);
+		_capture_state = Running;
+	}
+
 	sr_session_run();
 	sr_session_destroy();
 }
diff --git a/pv/sigsession.h b/pv/sigsession.h
index 307330ec..8da89d09 100644
--- a/pv/sigsession.h
+++ b/pv/sigsession.h
@@ -47,6 +47,12 @@ class SigSession : public QObject
 {
 	Q_OBJECT
 
+public:
+	enum capture_state {
+		Stopped,
+		Running
+	};
+
 public:
 	SigSession();
 
@@ -54,9 +60,13 @@ public:
 
 	void load_file(const std::string &name);
 
+	capture_state get_capture_state() const;
+
 	void start_capture(struct sr_dev_inst* sdi, uint64_t record_length,
 		uint64_t sample_rate);
 
+	void stop_capture();
+
 	std::vector< boost::shared_ptr<view::Signal> >
 		get_signals();
 
@@ -73,6 +83,9 @@ private:
 		struct sr_datafeed_packet *packet);
 
 private:
+	mutable boost::mutex _state_mutex;
+	capture_state _capture_state;
+
 	mutable boost::mutex _signals_mutex;
 	std::vector< boost::shared_ptr<view::Signal> > _signals;
 
-- 
2.30.2