Add pause/resume to the batch converter (#1248).

Add some missing locking to JobManager::decrease_priority.

4 files changed, 85 insertions, 23 deletions

diff --git a/src/lib/job.cc b/src/lib/job.cc
index 06416d1fe..ec6d5d306 100644
--- a/src/lib/job.cc
+++ b/src/lib/job.cc
@@ -519,13 +519,27 @@ Job::cancel ()
 	_thread = 0;
 }
 
-void
+/** @return true if the job was paused, false if it was not running */
+bool
 Job::pause_by_user ()
 {
-	if (running ()) {
-		set_state (PAUSED_BY_USER);
+	bool paused = false;
+	{
+		boost::mutex::scoped_lock lm (_state_mutex);
+		/* We can set _state here directly because we have a lock and we aren't
+		   setting the job to FINISHED_*
+		*/
+		if (_state == RUNNING) {
+			paused = true;
+			_state = PAUSED_BY_USER;
+		}
+	}
+
+	if (paused) {
 		_pause_changed.notify_all ();
 	}
+
+	return paused;
 }
 
 void
diff --git a/src/lib/job.h b/src/lib/job.h
index e5552e49e..d2691a3cb 100644
--- a/src/lib/job.h
+++ b/src/lib/job.h
@@ -50,7 +50,7 @@ public:
 	virtual void run () = 0;
 
 	void start ();
-	void pause_by_user ();
+	bool pause_by_user ();
 	void pause_by_priority ();
 	void resume ();
 	void cancel ();
diff --git a/src/lib/job_manager.cc b/src/lib/job_manager.cc
index 6d651d2ba..535830c0c 100644
--- a/src/lib/job_manager.cc
+++ b/src/lib/job_manager.cc
@@ -44,6 +44,7 @@ JobManager* JobManager::_instance = 0;
 
 JobManager::JobManager ()
 	: _terminate (false)
+	, _paused (false)
 	, _scheduler (0)
 {
 
@@ -150,21 +151,23 @@ JobManager::scheduler ()
 				return;
 			}
 
-			BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
+			if (!_paused) {
+				BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 
-				if (!i->finished ()) {
-					active_job = i->json_name ();
-				}
+					if (!i->finished ()) {
+						active_job = i->json_name ();
+					}
 
-				if (i->running ()) {
-					/* Something is already happening */
-					break;
-				}
+					if (i->running ()) {
+						/* Something is already happening */
+						break;
+					}
 
-				if (i->is_new()) {
-					i->start ();
-					/* Only start one job at once */
-					break;
+					if (i->is_new()) {
+						i->start ();
+						/* Only start one job at once */
+						break;
+					}
 				}
 			}
 		}
@@ -284,13 +287,16 @@ JobManager::decrease_priority (shared_ptr<Job> job)
 {
 	bool changed = false;
 
- 	for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
-		list<shared_ptr<Job> >::iterator next = i;
-		++next;
-		if (*i == job && next != _jobs.end()) {
-			swap (*i, *next);
-			changed = true;
-			break;
+	{
+		boost::mutex::scoped_lock lm (_mutex);
+		for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
+			list<shared_ptr<Job> >::iterator next = i;
+			++next;
+			if (*i == job && next != _jobs.end()) {
+				swap (*i, *next);
+				changed = true;
+				break;
+			}
 		}
 	}
 
@@ -298,3 +304,37 @@ JobManager::decrease_priority (shared_ptr<Job> job)
 		priority_changed ();
 	}
 }
+
+void
+JobManager::pause ()
+{
+	boost::mutex::scoped_lock lm (_mutex);
+
+	if (_paused) {
+		return;
+	}
+
+	BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
+		if (i->pause_by_user()) {
+			_paused_job = i;
+		}
+	}
+
+	_paused = true;
+}
+
+void
+JobManager::resume ()
+{
+	boost::mutex::scoped_lock lm (_mutex);
+	if (!_paused) {
+		return;
+	}
+
+	if (_paused_job) {
+		_paused_job->resume ();
+	}
+
+	_paused_job.reset ();
+	_paused = false;
+}
diff --git a/src/lib/job_manager.h b/src/lib/job_manager.h
index a382dd736..aafb7aa67 100644
--- a/src/lib/job_manager.h
+++ b/src/lib/job_manager.h
@@ -47,6 +47,12 @@ public:
 	bool errors () const;
 	void increase_priority (boost::shared_ptr<Job>);
 	void decrease_priority (boost::shared_ptr<Job>);
+	void pause ();
+	void resume ();
+	bool paused () const {
+		boost::mutex::scoped_lock lm (_mutex);
+		return _paused;
+	}
 
 	void analyse_audio (
 		boost::shared_ptr<const Film> film,
@@ -77,6 +83,8 @@ private:
 	/** List of jobs in the order that they will be executed */
 	std::list<boost::shared_ptr<Job> > _jobs;
 	bool _terminate;
+	bool _paused;
+	boost::shared_ptr<Job> _paused_job;
 
 	boost::optional<std::string> _last_active_job;
 	boost::thread* _scheduler;