decoder_control: add attributes start_ms, end_ms

Don't read song.start_ms and song.end_ms, let the player thread manage
this logic instead.

src/decoder_api.c

@@ -132,7 +132,7 @@ decoder_command_finished(struct decoder *decoder)
 		assert(music_pipe_empty(dc->pipe));
 
 		decoder->initial_seek_running = false;
-		decoder->timestamp = dc->song->start_ms / 1000.;
+		decoder->timestamp = dc->start_ms / 1000.;
 		decoder_unlock(dc);
 		return;
 	}
@@ -165,7 +165,7 @@ double decoder_seek_where(G_GNUC_UNUSED struct decoder * decoder)
 	assert(dc->pipe != NULL);
 
 	if (decoder->initial_seek_running)
-		return dc->song->start_ms / 1000.;
+		return dc->start_ms / 1000.;
 
 	assert(dc->command == DECODE_COMMAND_SEEK);
 
@@ -407,8 +407,8 @@ decoder_data(struct decoder *decoder,
 		decoder->timestamp += (double)nbytes /
 			audio_format_time_to_size(&dc->out_audio_format);
 
-		if (dc->song->end_ms > 0 &&
+		if (dc->end_ms > 0 &&
-		    decoder->timestamp >= dc->song->end_ms / 1000.0)
+		    decoder->timestamp >= dc->end_ms / 1000.0)
 			/* the end of this range has been reached:
 			   stop decoding */
 			return DECODE_COMMAND_STOP;

src/decoder_control.c

@@ -102,6 +102,7 @@ dc_command_async(struct decoder_control *dc, enum decoder_command cmd)
 
 void
 dc_start(struct decoder_control *dc, struct song *song,
+	 unsigned start_ms, unsigned end_ms,
 	 struct music_buffer *buffer, struct music_pipe *pipe)
 {
 	assert(song != NULL);
@@ -110,6 +111,8 @@ dc_start(struct decoder_control *dc, struct song *song,
 	assert(music_pipe_empty(pipe));
 
 	dc->song = song;
+	dc->start_ms = start_ms;
+	dc->end_ms = end_ms;
 	dc->buffer = buffer;
 	dc->pipe = pipe;
 	dc_command(dc, DECODE_COMMAND_START);

src/decoder_control.h

@@ -79,6 +79,23 @@ struct decoder_control {
 	 */
 	const struct song *song;
 
+	/**
+	 * The initial seek position (in milliseconds), e.g. to the
+	 * start of a sub-track described by a CUE file.
+	 *
+	 * This attribute is set by dc_start().
+	 */
+	unsigned start_ms;
+
+	/**
+	 * The decoder will stop when it reaches this position (in
+	 * milliseconds).  0 means don't stop before the end of the
+	 * file.
+	 *
+	 * This attribute is set by dc_start().
+	 */
+	unsigned end_ms;
+
 	float total_time;
 
 	/** the #music_chunk allocator */
@@ -225,11 +242,14 @@ dc_command_wait(struct decoder_control *dc);
  *
  * @param the decoder
  * @param song the song to be decoded
+ * @param start_ms see #decoder_control
+ * @param end_ms see #decoder_control
  * @param pipe the pipe which receives the decoded chunks (owned by
  * the caller)
  */
 void
 dc_start(struct decoder_control *dc, struct song *song,
+	 unsigned start_ms, unsigned end_ms,
 	 struct music_buffer *buffer, struct music_pipe *pipe);
 
 void

src/decoder_thread.c

@@ -369,7 +369,7 @@ decoder_run_song(struct decoder_control *dc,
 {
 	struct decoder decoder = {
 		.dc = dc,
-		.initial_seek_pending = song->start_ms > 0,
+		.initial_seek_pending = dc->start_ms > 0,
 		.initial_seek_running = false,
 	};
 	int ret;

src/player_thread.c

@@ -145,7 +145,9 @@ player_dc_start(struct player *player, struct music_pipe *pipe)
 	assert(player->queued || pc.command == PLAYER_COMMAND_SEEK);
 	assert(pc.next_song != NULL);
 
-	dc_start(dc, pc.next_song, player_buffer, pipe);
+	dc_start(dc, pc.next_song,
+		 pc.next_song->start_ms, pc.next_song->end_ms,
+		 player_buffer, pipe);
 }
 
 /**