driver: Create an audio driver class

The driver is used to select between gstreamer playback and a fake
playback mode used only when testing.

Currently the GSTDriver has empty functions.  It will be implemented as
the audio.cpp file is updated.

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

DESIGN

@@ -1299,6 +1299,68 @@ Deck:
 		Return the RecentQueue to the caller.
 
 
+Audio Driver:
+	The audio driver creates a way to fake audio playback for testing.  This
+	will allow for more accurate tests, since I will know in advance what
+	values are returned to the Audio layer.  This layer will derive from
+	the Driver class to implement either the GSTDriver or the TestDriver.
+
+- Driver:
+	class Driver {
+	protected:
+		void (*on_eos)();
+
+	public:
+		Driver();
+		~Driver();
+		virtual void init(int *, char ***, void (*)()) = 0;
+
+		virtual void load(const std::string &) = 0;
+		virtual void play() = 0;
+		virtual void pause() = 0;
+
+		virtual void seek_to(long) = 0;
+		virtual long position() = 0;
+		virtual long duration() = 0
+	};
+
+- Driver API:
+	void Driver :: Driver();
+		Initialize the audio driver.  This involves setting up a GST
+		Bus in the GSTDriver case.
+
+	void Driver :: ~Driver();
+		In the GSTDriver case, call gst_deinit() to avoid memory leak
+		false positives.
+
+	void Driver :: init(int argc, char **argv, void (*eos_cb)());
+		The GSTDriver will use this function to set up the playbin2.
+		When an end-of-stream message is received, call eos_cb().
+
+	void Driver :: load(const std::string &file);
+		Load file for playback, but do not begin playback yet.
+
+	void Driver :: play();
+		Start playback.
+
+	void Driver :: pause();
+		Pause playback.
+
+	void Driver :: seek_to(long pos);
+		Change playback position in the current track in nanoseconds.
+
+	long Driver :: position();
+		Return the current position in the track in nanoseconds.
+
+	long Driver :: duration();
+		Return the duration of the track in nanoseconds.
+
+- API:
+	Driver *driver :: get_driver();
+		Return the current driver to be used for audio playback.  This
+		could be either the GSTDriver or the TestDriver depending on
+		if CONFIG_TEST is set when compiling.
+
 
 
 

include/driver.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2014 (c) Anna Schumaker.
+ */
+
+#include <string>
+
+class Driver {
+protected:
+	void (*on_eos)();
+
+public:
+	Driver();
+	~Driver();
+	virtual void init(int *, char ***, void (*)()) = 0;
+
+	virtual void load(const std::string &) = 0;
+	virtual void play() = 0;
+	virtual void pause() = 0;
+
+	virtual void seek_to(long) = 0;
+	virtual long position() = 0;
+	virtual long duration() = 0;
+};
+
+
+#ifdef CONFIG_TEST
+class TestDriver : public Driver
+{
+public:
+	bool playing;
+	long cur_pos;
+	long cur_duration;
+	std::string cur_file;
+
+	TestDriver();
+	~TestDriver();
+	void init(int *, char ***, void (*)());
+
+	void load(const std::string &);
+	void play();
+	void pause();
+
+	void seek_to(long);
+	long position();
+	long duration();
+
+	void eos();
+};
+#else /* CONFIG_TEST */
+class GSTDriver : public Driver
+{
+public:
+	GSTDriver();
+	~GSTDriver();
+	void init(int *, char ***, void (*)());
+
+	void load(const std::string &);
+	void play();
+	void pause();
+
+	void seek_to(long);
+	long position();
+	long duration();
+};
+#endif /* CONFIG_TEST */
+
+
+
+namespace driver
+{
+
+	Driver *get_driver();
+
+}

lib/driver.cpp

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2014 (c) Anna Schumaker.
+ */
+#include <driver.h>
+
+
+Driver :: Driver() {}
+Driver :: ~Driver() {}
+
+
+#ifdef CONFIG_TEST
+
+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 :: load(const std::string &file) { cur_file = file; }
+void TestDriver :: play()  { playing = true;  }
+void TestDriver :: pause() { playing = false; }
+
+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(); }
+
+#else /* CONFIG_TEST */
+
+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() { }
+
+void GSTDriver :: seek_to(long pos) { }
+long GSTDriver :: position() { return 0; }
+long GSTDriver :: duration() { return 0; }
+
+#endif /* CONFIG_TEST */
+
+
+#ifdef CONFIG_TEST
+static TestDriver cur_driver;
+#else /* CONFIG_TEST */
+static GSTDriver cur_driver;
+#endif /* CONFIG_TEST */
+
+
+Driver *driver :: get_driver()
+{
+	return &cur_driver;
+}

tests/.gitignore

@@ -10,3 +10,4 @@ queue
 library
 playlist
 deck
+driver

tests/Sconscript

@@ -21,6 +21,7 @@ tests = [
 	("library.cpp",  True,  [ "idle.cpp" ], []),
 	("playlist.cpp", True,  [], []),
 	("deck.cpp",     True,  [], []),
+	("driver.cpp",   False, [ "driver.cpp" ], []),
 
 ]
 

tests/driver.cpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2014 (c) Anna Schumaker.
+ */
+#include <driver.h>
+#include "test.h"
+
+static TestDriver *DRIVER_NULL = NULL;
+static unsigned int eos_count = 0;
+
+void on_eos()
+{
+	eos_count++;
+}
+
+void test_driver()
+{
+	TestDriver *driver = (TestDriver *)driver :: get_driver();
+	const std::string file = "/home/Zelda/Music/Wind Waker/1 - Outset Isle.ogg";
+
+	test_not_equal(driver, DRIVER_NULL);
+
+	driver->init(0, NULL, on_eos);
+
+	driver->load(file);
+	test_equal(driver->cur_file, file);
+
+	driver->play();
+	test_equal(driver->playing, true);
+	driver->pause();
+	test_equal(driver->playing, false);
+
+	driver->seek_to(4242);
+	test_equal(driver->cur_pos, (long)4242);
+	test_equal(driver->position(), (long)4242);
+
+	driver->cur_duration = 424242;
+	test_equal(driver->duration(), (long)424242);
+
+	driver->eos();
+	test_equal(eos_count, (unsigned)1);
+}
+
+int main(int argc, char **argv)
+{
+	run_test("Test Audio Driver", test_driver);
+	return 0;
+}