/**
* The main thread of the music player. Handles events and coverts
* samples to play a song.
*/
static void *music_player_main(struct music_player_t *self_p)
{
uint32_t mask;
struct time_t timeout;
thrd_set_name("music_player");
/* Start the periodic fill timer. */
timeout.seconds = 0;
timeout.nanoseconds = 10000000;
timer_init(&self_p->timer,
&timeout,
(void (*)(void *))fill_timer_cb,
self_p,
TIMER_PERIODIC);
timer_start(&self_p->timer);
/* Start the main loop of the music player. */
while (1) {
mask = (EVENT_PLAY
| EVENT_PAUSE
| EVENT_STOP
| EVENT_TIMEOUT);
event_read(&self_p->event, &mask, sizeof(mask));
if (mask & EVENT_STOP) {
handle_event_stop(self_p);
}
if (mask & EVENT_PAUSE) {
handle_event_pause(self_p);
}
if (mask & EVENT_PLAY) {
handle_event_play(self_p);
}
/* Play if the state in playing, eyy! */
if (self_p->state == STATE_PLAYING) {
play_chunk(self_p);
}
}
return (NULL);
}
/**
* Obtains the next chunk from the music pipe, optionally applies
* cross-fading, and sends it to all audio outputs.
*
* @return true on success, false on error (playback will be stopped)
*/
static bool
play_next_chunk(struct player *player)
{
struct player_control *pc = player->pc;
struct decoder_control *dc = player->dc;
if (!audio_output_all_wait(pc, 64))
/* the output pipe is still large enough, don't send
another chunk */
return true;
unsigned cross_fade_position;
struct music_chunk *chunk = NULL;
if (player->xfade == XFADE_ENABLED &&
player_dc_at_next_song(player) &&
(cross_fade_position = music_pipe_size(player->pipe))
<= player->cross_fade_chunks) {
/* perform cross fade */
struct music_chunk *other_chunk =
music_pipe_shift(dc->pipe);
if (!player->cross_fading) {
/* beginning of the cross fade - adjust
crossFadeChunks which might be bigger than
the remaining number of chunks in the old
song */
player->cross_fade_chunks = cross_fade_position;
player->cross_fading = true;
}
if (other_chunk != NULL) {
chunk = music_pipe_shift(player->pipe);
assert(chunk != NULL);
assert(chunk->other == NULL);
/* don't send the tags of the new song (which
is being faded in) yet; postpone it until
the current song is faded out */
player->cross_fade_tag =
tag_merge_replace(player->cross_fade_tag,
other_chunk->tag);
other_chunk->tag = NULL;
if (isnan(pc->mixramp_delay_seconds)) {
chunk->mix_ratio = ((float)cross_fade_position)
/ player->cross_fade_chunks;
} else {
chunk->mix_ratio = nan("");
}
if (music_chunk_is_empty(other_chunk)) {
/* the "other" chunk was a music_chunk
which had only a tag, but no music
data - we cannot cross-fade that;
but since this happens only at the
beginning of the new song, we can
easily recover by throwing it away
now */
music_buffer_return(player_buffer,
other_chunk);
other_chunk = NULL;
}
chunk->other = other_chunk;
} else {
/* there are not enough decoded chunks yet */
decoder_lock(dc);
if (decoder_is_idle(dc)) {
/* the decoder isn't running, abort
cross fading */
decoder_unlock(dc);
player->xfade = XFADE_DISABLED;
} else {
/* wait for the decoder */
decoder_signal(dc);
player_wait_decoder(pc, dc);
decoder_unlock(dc);
return true;
}
}
}
if (chunk == NULL)
chunk = music_pipe_shift(player->pipe);
assert(chunk != NULL);
/* insert the postponed tag if cross-fading is finished */
if (player->xfade != XFADE_ENABLED && player->cross_fade_tag != NULL) {
chunk->tag = tag_merge_replace(chunk->tag,
player->cross_fade_tag);
player->cross_fade_tag = NULL;
}
/* play the current chunk */
if (!play_chunk(player->pc, player->song, chunk,
&player->play_audio_format)) {
music_buffer_return(player_buffer, chunk);
player_lock(pc);
pc->error = PLAYER_ERROR_AUDIO;
/* pause: the user may resume playback as soon as an
audio output becomes available */
pc->state = PLAYER_STATE_PAUSE;
player->paused = true;
player_unlock(pc);
return false;
}
/* this formula should prevent that the decoder gets woken up
with each chunk; it is more efficient to make it decode a
larger block at a time */
decoder_lock(dc);
if (!decoder_is_idle(dc) &&
music_pipe_size(dc->pipe) <= (pc->buffered_before_play +
music_buffer_size(player_buffer) * 3) / 4)
decoder_signal(dc);
decoder_unlock(dc);
return true;
}
