music_pipe: added music_pipe_peek()

music_pipe_peek() is similar to music_pipe_shift(), but doesn't remove
the chunk.  This allows it to be used with a "const" music_pipe.

2 files changed, 13 insertions, 0 deletions

diff --git a/src/pipe.c b/src/pipe.c
index d02a00a04..320c5c3a3 100644
--- a/src/pipe.c
+++ b/src/pipe.c
@@ -61,6 +61,12 @@ music_pipe_free(struct music_pipe *mp)
 	g_free(mp);
 }
 
+const struct music_chunk *
+music_pipe_peek(const struct music_pipe *mp)
+{
+	return mp->head;
+}
+
 struct music_chunk *
 music_pipe_shift(struct music_pipe *mp)
 {
diff --git a/src/pipe.h b/src/pipe.h
index f1a231542..7ed6c917d 100644
--- a/src/pipe.h
+++ b/src/pipe.h
@@ -41,6 +41,13 @@ void
 music_pipe_free(struct music_pipe *mp);
 
 /**
+ * Returns the first #music_chunk from the pipe.  Returns NULL if the
+ * pipe is empty.
+ */
+const struct music_chunk *
+music_pipe_peek(const struct music_pipe *mp);
+
+/**
  * Removes the first chunk from the head, and returns it.
  */
 struct music_chunk *