crossfade: copy chunk.audio_format in !NDEBUG

When the destination chunk was empty in cross_fade_apply(), it had no
audio_format attached (an attribute which is only used for assertion
in the debug build).  cross_fade_apply() should assign it the
audio_format of the second chunk (if available), otherwise MPD will
crash.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/crossfade.c b/src/crossfade.c
index 2bac4a649..8d752cf5f 100644
--- a/src/crossfade.c
+++ b/src/crossfade.c
@@ -58,6 +58,10 @@ void cross_fade_apply(struct music_chunk *a, const struct music_chunk *b,
 {
 	size_t size;
 
+	assert(a != NULL);
+	assert(b != NULL);
+	assert(a->length == 0 || b->length == 0 ||
+	       audio_format_equals(&a->audio_format, b->audio_format));
 	assert(current_chunk <= num_chunks);
 
 	if (a->tag == NULL && b->tag != NULL)
@@ -79,6 +83,12 @@ void cross_fade_apply(struct music_chunk *a, const struct music_chunk *b,
 		   there is unmixed rest at the end.  Copy it over.
 		   The output buffer API guarantees that there is
 		   enough room in a->data. */
+
+#ifndef NDEBUG
+		if (a->length == 0)
+			a->audio_format = b->audio_format;
+#endif
+
 		memcpy(a->data + a->length,
 		       b->data + a->length,
 		       b->length - a->length);