driver: Move Gst code into the GstDriver

This would have to happen eventually.  Might as well do it now!

I also updated the TestDriver test to match the changes I had to make.

Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>

DESIGN

@@ -1313,11 +1313,12 @@ Audio Driver:
 	public:
 		Driver();
 		~Driver();
-		virtual void init(int *, char ***, void (*)()) = 0;
+		virtual void init(int *, char ***, void (*)(), void (*)()) = 0;
 
 		virtual void load(const std::string &) = 0;
 		virtual void play() = 0;
 		virtual void pause() = 0;
+		virtual void is_playing() = 0;
 
 		virtual void seek_to(long) = 0;
 		virtual long position() = 0;
@@ -1333,18 +1334,25 @@ Audio Driver:
 		In the GSTDriver case, call gst_deinit() to avoid memory leak
 		false positives.
 
-	void Driver :: init(int argc, char **argv, void (*eos_cb)());
+	void Driver :: init(int argc, char **argv, void (*eos_cb)(),
+			    void (*error_cb)());
 		The GSTDriver will use this function to set up the playbin2.
 		When an end-of-stream message is received, call eos_cb().
+		If there is an error, call error_cb();
 
 	void Driver :: load(const std::string &file);
 		Load file for playback, but do not begin playback yet.
 
 	void Driver :: play();
-		Start playback.
+		Start playback.  Return true if the state change operation
+		succeeds, false otherwise.
 
 	void Driver :: pause();
-		Pause playback.
+		Pause playback.  Return true if the state change operation
+		succeeds, false otherwise.
+
+	bool Driver :: is_playing();
+		Return true if the player is currently playing, false otherwise.
 
 	void Driver :: seek_to(long pos);
 		Change playback position in the current track in nanoseconds.

include/audio.h

@@ -7,10 +7,6 @@
 #include <error.h>
 #include <queue.h>
 
-extern "C" {
-	#include <gst/gst.h>
-}
-
 #include <string>
 
 namespace audio

include/driver.h

@@ -7,15 +7,17 @@
 class Driver {
 protected:
 	void (*on_eos)();
+	void (*on_error)();
 
 public:
 	Driver();
 	~Driver();
-	virtual void init(int *, char ***, void (*)()) = 0;
+	virtual void init(int *, char ***, void (*)(), void (*)()) = 0;
 
 	virtual void load(const std::string &) = 0;
-	virtual void play() = 0;
-	virtual void pause() = 0;
+	virtual bool play() = 0;
+	virtual bool pause() = 0;
+	virtual bool is_playing() = 0;
 
 	virtual void seek_to(long) = 0;
 	virtual long position() = 0;
@@ -34,38 +36,50 @@ public:
 
 	TestDriver();
 	~TestDriver();
-	void init(int *, char ***, void (*)());
+	void init(int *, char ***, void (*)(), void (*)());
 
 	void load(const std::string &);
-	void play();
-	void pause();
+	bool play();
+	bool pause();
+	bool is_playing();
 
 	void seek_to(long);
 	long position();
 	long duration();
 
 	void eos();
+	void error();
 };
-#else /* CONFIG_TEST */
+#else /* !CONFIG_TEST */
+
+#include <gst/gst.h>
+
 class GSTDriver : public Driver
 {
+private:
+	GstElement *player;
+	std::string cur_file;
+	bool change_state(GstState state);
+
 public:
 	GSTDriver();
 	~GSTDriver();
-	void init(int *, char ***, void (*)());
+	void init(int *, char ***, void (*)(), void (*)());
 
 	void load(const std::string &);
-	void play();
-	void pause();
+	bool play();
+	bool pause();
+	bool is_playing();
 
 	void seek_to(long);
 	long position();
 	long duration();
+
+	void on_message(GstMessage *);
 };
 #endif /* CONFIG_TEST */
 
 
-
 namespace driver
 {
 

lib/audio.cpp

@@ -4,13 +4,12 @@
 #include <audio.h>
 #include <callback.h>
 #include <deck.h>
+#include <driver.h>
 #include <library.h>
 
 #include <sstream>
 #include <string.h>
 
-static GstElement *ocarina_player;
-
 static bool player_playing = false;
 static bool track_loaded = false;
 static unsigned int cur_trackid = 0;
@@ -22,19 +21,6 @@ static bool o_should_pause = false;
 static File f_cur_track("cur_track", 0);
 
 
-static void parse_error(GstMessage *error)
-{
-	GError *err;
-	gchar  *debug;
-	Track *track = tagdb :: lookup(cur_trackid);
-
-	gst_message_parse_error(error, &err, &debug);
-	g_print("Error playing file: %s\n", track->path().c_str());
-	g_print("Error: %s\n", err->message);
-	g_error_free(err);
-	g_free(debug);
-}
-
 static void handle_pause_count()
 {
 	if (o_pause_enabled == false)
@@ -48,45 +34,24 @@ static void handle_pause_count()
 	get_callbacks()->on_pause_count_changed(o_pause_enabled, o_pause_count);
 }
 
-static gboolean on_message(GstBus *bus, GstMessage *message, gpointer data)
+static void on_error()
+{
+	audio :: next();
+	audio :: play();
+}
+
+static void on_eos()
 {
 	Track *track;
 
-	switch (GST_MESSAGE_TYPE(message)) {
-	case GST_MESSAGE_ERROR:
-		parse_error(message);
-		audio :: next();
-		audio :: play();
-		break;
-	case GST_MESSAGE_EOS:
-		handle_pause_count();
-		track = tagdb :: lookup(cur_trackid);
-		if (track) {
-			track->played();
-			library :: get_queue()->updated(track);
-		}
-		audio :: next();
-		audio :: seek_to(0);
-	default:
-		break;
-	}
-	return TRUE;
-}
-
-static bool change_state(GstState state)
-{
-	GstStateChangeReturn ret;
-
-	ret = gst_element_set_state(GST_ELEMENT(ocarina_player), state);
-	switch (ret) {
-	case GST_STATE_CHANGE_SUCCESS:
-	case GST_STATE_CHANGE_ASYNC:
-		player_playing = (state == GST_STATE_PLAYING);
-		return true;
-	default:
-		player_playing = false;
-		return false;
+	handle_pause_count();
+	track = tagdb :: lookup(cur_trackid);
+	if (track) {
+		track->played();
+		library :: get_queue()->updated(track);
 	}
+	audio :: next();
+	audio :: seek_to(0);
 }
 
 static void save_state()
@@ -98,37 +63,25 @@ static void save_state()
 
 static bool load_song(Track *track)
 {
-	GstState state;
-	gchar *uri;
-	std::string filepath = track->path();
+	bool start_playback;
 
-	if (o_should_pause == true) {
-		state = GST_STATE_PAUSED;
-		o_should_pause = false;
-	} else {
-		gst_element_get_state(GST_ELEMENT(ocarina_player), &state,
-					NULL, GST_CLOCK_TIME_NONE);
-	}
-
-	change_state(GST_STATE_NULL);
-	uri = gst_filename_to_uri(filepath.c_str(), NULL);
-	g_object_set(G_OBJECT(ocarina_player), "uri", uri, NULL);
-	g_free(uri);
+	if (o_should_pause)
+		start_playback = false;
+	else
+		start_playback = driver :: get_driver()->is_playing();
 
+	driver :: get_driver()->load(track->path());
 	get_callbacks()->on_track_loaded(track);
-	return change_state(state);
+
+	if (start_playback)
+		return driver :: get_driver()->play();
+	else
+		return driver :: get_driver()->pause();
 }
 
 void audio :: init(int *argc, char ***argv)
 {
-	GstBus *bus;
-
-	gst_init(argc, argv);
-
-	ocarina_player = gst_element_factory_make("playbin", "ocarina_player");
-	bus = gst_pipeline_get_bus(GST_PIPELINE(ocarina_player));
-
-	gst_bus_add_watch(bus, on_message, NULL);
+	driver :: get_driver()->init(argc, argv, on_eos, on_error);
 }
 
 void audio :: load_state()
@@ -144,15 +97,13 @@ void audio :: load_state()
 
 void audio :: quit()
 {
-	change_state(GST_STATE_NULL);
-	gst_deinit();
 }
 
 void audio :: play()
 {
 	if (track_loaded == false)
 		return;
-	if (change_state(GST_STATE_PLAYING))
+	if (driver :: get_driver()->play())
 		get_callbacks()->on_play();
 }
 
@@ -160,7 +111,7 @@ void audio :: pause()
 {
 	if (track_loaded == false)
 		return;
-	if (change_state(GST_STATE_PAUSED))
+	if (driver :: get_driver()->pause())
 		get_callbacks()->on_pause();
 }
 
@@ -180,15 +131,9 @@ void audio :: stop()
 
 void audio :: seek_to(long pos)
 {
-	bool ret;
 	if (track_loaded == false)
 		return;
-	ret = gst_element_seek_simple(GST_ELEMENT(ocarina_player),
-					GST_FORMAT_TIME,
-					GST_SEEK_FLAG_FLUSH,
-					pos);
-	if (!ret)
-		throw -E_AUDIO;
+	driver :: get_driver()->seek_to(pos);
 }
 
 void audio :: next()
@@ -245,13 +190,9 @@ unsigned int audio :: current_trackid()
 
 long audio :: position()
 {
-	long position;
-
 	if (track_loaded == false)
 		return 0;
-	if (!gst_element_query_position(GST_ELEMENT(ocarina_player), GST_FORMAT_TIME, &position))
-		return 0;
-	return position;
+	return driver :: get_driver()->position();
 }
 
 std::string audio :: position_str()
@@ -270,13 +211,9 @@ std::string audio :: position_str()
 
 long audio :: duration()
 {
-	long duration;
-
 	if (track_loaded == false)
 		return 0;
-	if (!gst_element_query_duration(ocarina_player, GST_FORMAT_TIME, &duration))
-		return 0;
-	return duration;
+	return driver :: get_driver()->duration();
 }
 
 void audio :: pause_after(bool enabled, unsigned int n)

lib/driver.cpp

@@ -13,30 +13,134 @@ Driver :: ~Driver() {}
 TestDriver :: TestDriver() : playing(false), cur_pos(0), cur_duration(0) {}
 TestDriver :: ~TestDriver() {}
 
-void TestDriver :: init(int *argc, char ***argv, void (*eos_cb)()) { on_eos = eos_cb; }
+void TestDriver :: init(int *argc, char ***argv, void (*eos_cb)(), void (*error_cb)())
+	{ on_eos = eos_cb; on_error = error_cb; }
 void TestDriver :: load(const std::string &file) { cur_file = file; }
-void TestDriver :: play()  { playing = true;  }
-void TestDriver :: pause() { playing = false; }
+bool TestDriver :: play()  { playing = true;  return true; }
+bool TestDriver :: pause() { playing = false; return true; }
+bool TestDriver :: is_playing() { return playing; }
 
 void TestDriver :: seek_to(long pos) { cur_pos = pos; }
 long TestDriver :: position() { return cur_pos;      }
 long TestDriver :: duration() { return cur_duration; }
 
-void TestDriver :: eos() { on_eos(); }
+void TestDriver :: eos()   { on_eos();   }
+void TestDriver :: error() { on_error(); }
 
 #else /* CONFIG_TEST */
 
+static gboolean on_gst_message(GstBus *bus, GstMessage *message, gpointer data)
+{
+	GSTDriver *driver = (GSTDriver *)data;
+	driver->on_message(message);
+	return TRUE;
+}
+
+static void parse_gst_error(GstMessage *error, const std::string filepath)
+{
+	GError *err;
+	gchar  *debug;
+
+	gst_message_parse_error(error, &err, &debug);
+	g_print("Error playing file: %s\n", filepath.c_str());
+	g_print("Error: %s\n", err->message);
+	g_error_free(err);
+	g_free(debug);
+}
+
 GSTDriver :: GSTDriver()  {}
-GSTDriver :: ~GSTDriver() {}
 
-void GSTDriver :: init(int argc, char **argv, void (*eos_cb)()) { }
-void GSTDriver :: load(const std::string &file) { }
-void GSTDriver :: play()  { }
-void GSTDriver :: pause() { }
+GSTDriver :: ~GSTDriver()
+{
+	change_state(GST_STATE_NULL);
+	gst_deinit();
+}
 
-void GSTDriver :: seek_to(long pos) { }
-long GSTDriver :: position() { return 0; }
-long GSTDriver :: duration() { return 0; }
+bool GSTDriver :: change_state(GstState state)
+{
+	GstStateChangeReturn ret = gst_element_set_state(player, state);
+	switch (ret) {
+	case GST_STATE_CHANGE_SUCCESS:
+	case GST_STATE_CHANGE_ASYNC:
+		return true;
+	default:
+		return false;
+	}
+}
+
+void GSTDriver :: init(int *argc, char ***argv, void (*eos_cb)(), void (*error_cb)())
+{
+	GstBus *bus;
+
+	on_eos   = eos_cb;
+	on_error = error_cb;
+
+	gst_init(argc, argv);
+	player = gst_element_factory_make("playbin", "ocarina_player");
+	bus    = gst_pipeline_get_bus(GST_PIPELINE(player));
+	gst_bus_add_watch(bus, on_gst_message, this);
+}
+
+void GSTDriver :: load(const std::string &filepath)
+{
+	gchar *uri;
+
+	cur_file = filepath;
+	change_state(GST_STATE_NULL);
+	uri = gst_filename_to_uri(filepath.c_str(), NULL);
+	g_object_set(G_OBJECT(player), "uri", uri, NULL);
+	g_free(uri);
+}
+
+bool GSTDriver :: play()
+{
+	return change_state(GST_STATE_PLAYING);
+}
+
+bool GSTDriver :: pause()
+{
+	return change_state(GST_STATE_PAUSED);
+}
+
+bool GSTDriver :: is_playing()
+{
+	GstState state;
+	gst_element_get_state(player, &state, NULL, GST_CLOCK_TIME_NONE);
+	return state == GST_STATE_PLAYING;
+}
+
+void GSTDriver :: seek_to(long pos)
+{
+	gst_element_seek_simple(player, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH, pos);
+}
+
+long GSTDriver :: position()
+{
+	long position;
+	if (gst_element_query_position(player, GST_FORMAT_TIME, &position))
+		return position;
+	return 0;
+}
+
+long GSTDriver :: duration()
+{
+	long duration;
+
+	if (gst_element_query_duration(player, GST_FORMAT_TIME, &duration))
+		return duration;
+	return 0;
+}
+
+void GSTDriver :: on_message(GstMessage *message)
+{
+	switch (GST_MESSAGE_TYPE(message)) {
+	case GST_MESSAGE_ERROR:
+		parse_gst_error(message, cur_file);
+		on_error();
+	default:
+		break;
+	}
+}
 
 #endif /* CONFIG_TEST */
 

tests/driver.cpp

@@ -6,12 +6,18 @@
 
 static TestDriver *DRIVER_NULL = NULL;
 static unsigned int eos_count = 0;
+static unsigned int error_count = 0;
 
 void on_eos()
 {
 	eos_count++;
 }
 
+void on_error()
+{
+	error_count++;
+}
+
 void test_driver()
 {
 	TestDriver *driver = (TestDriver *)driver :: get_driver();
@@ -19,15 +25,18 @@ void test_driver()
 
 	test_not_equal(driver, DRIVER_NULL);
 
-	driver->init(0, NULL, on_eos);
+	driver->init(0, NULL, on_eos, on_error);
 
 	driver->load(file);
 	test_equal(driver->cur_file, file);
 
-	driver->play();
+	test_equal(driver->play(),  true);
 	test_equal(driver->playing, true);
-	driver->pause();
+	test_equal(driver->is_playing(), true);
+
+	test_equal(driver->pause(), true);
 	test_equal(driver->playing, false);
+	test_equal(driver->is_playing(), false);
 
 	driver->seek_to(4242);
 	test_equal(driver->cur_pos, (long)4242);
@@ -38,6 +47,9 @@ void test_driver()
 
 	driver->eos();
 	test_equal(eos_count, (unsigned)1);
+
+	driver->error();
+	test_equal(error_count, (unsigned)1);
 }
 
 int main(int argc, char **argv)