GSoC/Buflib: Replace all direct accesses to audiobuf with buffer API functions.

Namely, introduce buffer_get_buffer() and buffer_release_buffer().
buffer_get_buffer() aquires all available and grabs a lock, attempting to
call buffer_alloc() or buffer_get_buffer() while this lock is locked will cause
a panicf() (doesn't actually happen, but is for debugging purpose).
buffer_release_buffer() unlocks that lock and can additionally increment the
audiobuf buffer to make an allocation. Pass 0 to only unlock if buffer was
used temporarily only.
buffer_available() is a replacement function to query audiobuflen, i.e. what's
left in the buffer.
Buffer init is moved up in the init chain and handles ipodvideo64mb internally.

Further changes happened to mp3data.c and talk.c as to not call the above API
functions, but get the buffer from callers. The caller is the audio system
which has the buffer lock while mp3data.c and talk mess with the buffer.
mpeg.c now implements some buffer related functions of playback.h, especially
audio_get_buffer(), allowing to reduce #ifdef hell a tiny bit.

audiobuf and audiobufend are local to buffer.c now.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30308 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 4 insertions, 2 deletions

diff --git a/firmware/export/audio.h b/firmware/export/audio.h
index 910791c7fd..6757bf143b 100644
--- a/firmware/export/audio.h
+++ b/firmware/export/audio.h
@@ -51,6 +51,8 @@
 void audio_init(void) INIT_ATTR;
 void audio_play(long offset);
 void audio_stop(void);
+/* Stops audio from serving playback and frees resources*/
+void audio_hard_stop(void);
 void audio_pause(void);
 void audio_resume(void);
 void audio_next(void);
@@ -68,11 +70,11 @@ void audio_error_clear(void);
 int audio_get_file_pos(void);
 void audio_beep(int duration);
 
-#if CONFIG_CODEC == SWCODEC
 /* Required call when audio buffer is required for some other purpose */
+/* implemented in apps but called from firmware(!) */
 unsigned char *audio_get_buffer(bool talk_buf, size_t *buffer_size); 
-/* only implemented in playback.c, but called from firmware */
 
+#if CONFIG_CODEC == SWCODEC
 void audio_next_dir(void);
 void audio_prev_dir(void);