music_pipe: more wrapper functions

Replace all direct music_pipe struct accesses with wrapper functions.
The compiled machine code is the same, but this way, we can change
struct internals more easily.

2 files changed, 33 insertions, 8 deletions

diff --git a/src/pipe.h b/src/pipe.h
index 10a3501ec..3af0bbd16 100644
--- a/src/pipe.h
+++ b/src/pipe.h
@@ -76,12 +76,30 @@ void music_pipe_flush(void);
  */
 void music_pipe_set_lazy(bool lazy);
 
+static inline unsigned
+music_pipe_size(void)
+{
+	return ob.size;
+}
+
 /** is the buffer empty? */
 static inline bool music_pipe_is_empty(void)
 {
 	return ob.begin == ob.end;
 }
 
+static inline bool
+music_pipe_head_is(unsigned i)
+{
+	return !music_pipe_is_empty() && ob.begin == i;
+}
+
+static inline unsigned
+music_pipe_tail_index(void)
+{
+	return ob.end;
+}
+
 void music_pipe_shift(void);
 
 /**
@@ -102,6 +120,15 @@ int music_pipe_absolute(const unsigned relative);
 struct music_chunk *
 music_pipe_get_chunk(const unsigned i);
 
+static inline struct music_chunk *
+music_pipe_peek(void)
+{
+	if (music_pipe_is_empty())
+		return NULL;
+
+	return music_pipe_get_chunk(ob.begin);
+}
+
 /**
  * Append a data block to the buffer.
  *
diff --git a/src/player_thread.c b/src/player_thread.c
index e1f11652e..3a378b069 100644
--- a/src/player_thread.c
+++ b/src/player_thread.c
@@ -330,7 +330,7 @@ static void do_play(void)
 			assert(pc.next_song != NULL);
 
 			player.queued = false;
-			player.next_song_chunk = ob.end;
+			player.next_song_chunk = music_pipe_tail_index();
 			dc_start_async(pc.next_song);
 		}
 		if (player.next_song_chunk >= 0 &&
@@ -342,7 +342,7 @@ static void do_play(void)
 			crossFadeChunks =
 				cross_fade_calc(pc.crossFade, dc.totalTime,
 						&dc.out_audio_format,
-						ob.size -
+						music_pipe_size() -
 						pc.buffered_before_play);
 			if (crossFadeChunks > 0) {
 				player.xfade = XFADE_ENABLED;
@@ -356,9 +356,8 @@ static void do_play(void)
 		if (player.paused)
 			notify_wait(&pc.notify);
 		else if (!music_pipe_is_empty() &&
-			 (int)ob.begin != player.next_song_chunk) {
-			struct music_chunk *beginChunk =
-				music_pipe_get_chunk(ob.begin);
+			 !music_pipe_head_is(player.next_song_chunk)) {
+			struct music_chunk *beginChunk = music_pipe_peek();
 			unsigned int fadePosition;
 			if (player.xfade == XFADE_ENABLED &&
 			    player.next_song_chunk >= 0 &&
@@ -409,10 +408,9 @@ static void do_play(void)
 			   decoder gets woken up with each chunk; it
 			   is more efficient to make it decode a
 			   larger block at a time */
-			if (music_pipe_available() <= (pc.buffered_before_play + ob.size * 3) / 4)
+			if (music_pipe_available() <= (pc.buffered_before_play + music_pipe_size() * 3) / 4)
 				notify_signal(&dc.notify);
-		} else if (!music_pipe_is_empty() &&
-			   (int)ob.begin == player.next_song_chunk) {
+		} else if (music_pipe_head_is(player.next_song_chunk)) {
 			/* at the beginning of a new song */
 
 			if (player.xfade == XFADE_ENABLED && nextChunk >= 0) {