moved code to crossfade.c

decode.c should be a lot smaller; start by moving all code which
handles cross-fading to crossfade.c.  Also includes camelCase
conversion.

src/Makefile.am

@@ -38,6 +38,7 @@ mpd_headers = \
 	command.h \
 	condition.h \
 	conf.h \
+	crossfade.h \
 	dbUtils.h \
 	decode.h \
 	decoder_api.h \
@@ -102,6 +103,7 @@ mpd_SOURCES = \
 	command.c \
 	condition.c \
 	conf.c \
+	crossfade.c \
 	dbUtils.c \
 	decode.c \
 	decoder_api.c \

src/crossfade.c

@@ -0,0 +1,62 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "crossfade.h"
+#include "audio.h"
+#include "pcm_utils.h"
+
+unsigned cross_fade_calc(float duration, float total_time,
+			 const AudioFormat * af,
+			 unsigned max_chunks)
+{
+	unsigned int chunks;
+
+	if (duration <= 0 || duration >= total_time ||
+	    !isCurrentAudioFormat(af))
+		return 0;
+
+	assert(duration > 0);
+	assert(af->bits > 0);
+	assert(af->channels > 0);
+	assert(af->sampleRate > 0);
+
+	chunks = audio_format_time_to_size(af) / CHUNK_SIZE;
+	chunks = (chunks * duration + 0.5);
+
+	if (chunks > max_chunks)
+		chunks = max_chunks;
+
+	return chunks;
+}
+
+void cross_fade_apply(ob_chunk * a, const ob_chunk * b,
+		      const AudioFormat * format,
+		      unsigned int current_chunk, unsigned int num_chunks)
+{
+	assert(current_chunk <= num_chunks);
+
+	pcm_mix(a->data,
+		b->data,
+		a->chunkSize,
+		b->chunkSize,
+		format,
+		((float)current_chunk) / num_chunks);
+	if (b->chunkSize > a->chunkSize)
+		a->chunkSize = b->chunkSize;
+}

src/crossfade.h

@@ -0,0 +1,34 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef CROSSFADE_H
+#define CROSSFADE_H
+
+#include "audio_format.h"
+#include "outputBuffer.h"
+
+unsigned cross_fade_calc(float duration, float total_time,
+			 const AudioFormat * af,
+			 unsigned max_chunks);
+
+void cross_fade_apply(ob_chunk * a, const ob_chunk * b,
+		      const AudioFormat * format,
+		      unsigned int current_chunk, unsigned int num_chunks);
+
+#endif

src/decode.c

@@ -27,6 +27,7 @@
 #include "ls.h"
 #include "main_notify.h"
 #include "audio.h"
+#include "crossfade.h"
 
 enum xfade_state {
 	XFADE_DISABLED = -1,
@@ -64,29 +65,6 @@ static void quitDecode(void)
 	wakeup_main_task();
 }
 
-static unsigned calculateCrossFadeChunks(AudioFormat * af,
-					 float totalTime, unsigned max_chunks)
-{
-	unsigned int chunks;
-
-	if (pc.crossFade == 0 || pc.crossFade >= totalTime ||
-	    !isCurrentAudioFormat(af))
-		return 0;
-
-	assert(pc.crossFade > 0);
-	assert(af->bits > 0);
-	assert(af->channels > 0);
-	assert(af->sampleRate > 0);
-
-	chunks = audio_format_time_to_size(af) / CHUNK_SIZE;
-	chunks = (chunks * pc.crossFade + 0.5);
-
-	if (chunks > max_chunks)
-		chunks = max_chunks;
-
-	return chunks;
-}
-
 static int waitOnDecode(int *decodeWaitedOn)
 {
 	while (dc.command == DECODE_COMMAND_START) {
@@ -360,23 +338,6 @@ void decoderInit(void)
 		FATAL("Failed to spawn decoder task: %s\n", strerror(errno));
 }
 
-static void crossFade(ob_chunk * a, ob_chunk * b,
-		      AudioFormat * format,
-		      unsigned int fadePosition, unsigned int crossFadeChunks)
-{
-	assert(fadePosition <= crossFadeChunks);
-
-	pcm_mix(a->data,
-		b->data,
-		a->chunkSize,
-		b->chunkSize,
-		format,
-		((float)fadePosition) /
-		crossFadeChunks);
-	if (b->chunkSize > a->chunkSize)
-		a->chunkSize = b->chunkSize;
-}
-
 static int playChunk(ob_chunk * chunk,
 		     const AudioFormat * format, double sizeToTime)
 {
@@ -498,10 +459,10 @@ static void decodeParent(void)
 			   calculate how many chunks will be required
 			   for it */
 			crossFadeChunks =
-				calculateCrossFadeChunks(&(ob.audioFormat),
+				cross_fade_calc(pc.crossFade, dc.totalTime,
-							 dc.totalTime,
+						&(ob.audioFormat),
-							 ob.size -
+						ob.size -
-							 buffered_before_play);
+						buffered_before_play);
 			if (crossFadeChunks > 0) {
 				do_xfade = XFADE_ENABLED;
 				nextChunk = -1;
@@ -531,11 +492,11 @@ static void decodeParent(void)
 				nextChunk = ob_absolute(crossFadeChunks);
 				if (nextChunk >= 0) {
 					ob_set_lazy(1);
-					crossFade(beginChunk,
+					cross_fade_apply(beginChunk,
-						  ob_get_chunk(nextChunk),
+							 ob_get_chunk(nextChunk),
-						  &(ob.audioFormat),
+							 &(ob.audioFormat),
-						  fadePosition,
+							 fadePosition,
-						  crossFadeChunks);
+							 crossFadeChunks);
 				} else {
 					/* there are not enough
 					   decoded chunks yet */