pcm_resample: renamed implementation functions

Added diversion functions to pcm_resample.c.  These check which
resampler is enabled at compile time (libsamplerate or fallback).
This prepares the following patch.

Makefile.am

@@ -101,6 +101,7 @@ mpd_headers = \
 	src/pcm_channels.h \
 	src/pcm_format.h \
 	src/pcm_resample.h \
+	src/pcm_resample_internal.h \
 	src/pcm_dither.h \
 	src/pcm_prng.h \
 	src/permission.h \

src/pcm_resample.c

@@ -17,7 +17,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#include "pcm_resample.h"
+#include "pcm_resample_internal.h"
 #include "config.h"
 
 #include <string.h>
@@ -33,3 +33,50 @@ void pcm_resample_init(struct pcm_resample_state *state)
 
 	pcm_buffer_init(&state->buffer);
 }
+
+void pcm_resample_deinit(struct pcm_resample_state *state)
+{
+#ifdef HAVE_LIBSAMPLERATE
+	pcm_resample_lsr_deinit(state);
+#else
+	pcm_resample_fallback_deinit(state);
+#endif
+}
+
+const int16_t *
+pcm_resample_16(struct pcm_resample_state *state,
+		uint8_t channels,
+		unsigned src_rate,
+		const int16_t *src_buffer, size_t src_size,
+		unsigned dest_rate,
+		size_t *dest_size_r)
+{
+#ifdef HAVE_LIBSAMPLERATE
+	return pcm_resample_lsr_16(state, channels,
+				   src_rate, src_buffer, src_size,
+				   dest_rate, dest_size_r);
+#else
+	return pcm_resample_fallback_16(state, channels,
+					src_rate, src_buffer, src_size,
+					dest_rate, dest_size_r);
+#endif
+}
+
+const int32_t *
+pcm_resample_32(struct pcm_resample_state *state,
+		uint8_t channels,
+		unsigned src_rate,
+		const int32_t *src_buffer, size_t src_size,
+		unsigned dest_rate,
+		size_t *dest_size_r)
+{
+#ifdef HAVE_LIBSAMPLERATE
+	return pcm_resample_lsr_32(state, channels,
+				   src_rate, src_buffer, src_size,
+				   dest_rate, dest_size_r);
+#else
+	return pcm_resample_fallback_32(state, channels,
+					src_rate, src_buffer, src_size,
+					dest_rate, dest_size_r);
+#endif
+}

src/pcm_resample_fallback.c

@@ -17,19 +17,20 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#include "pcm_resample.h"
+#include "pcm_resample_internal.h"
 
 #include <assert.h>
 #include <glib.h>
 
-void pcm_resample_deinit(struct pcm_resample_state *state)
+void
+pcm_resample_fallback_deinit(struct pcm_resample_state *state)
 {
 	pcm_buffer_deinit(&state->buffer);
 }
 
 /* resampling code blatantly ripped from ESD */
 const int16_t *
-pcm_resample_16(struct pcm_resample_state *state,
+pcm_resample_fallback_16(struct pcm_resample_state *state,
 			 uint8_t channels,
 			 unsigned src_rate,
 			 const int16_t *src_buffer, size_t src_size,
@@ -70,10 +71,11 @@ pcm_resample_16(struct pcm_resample_state *state,
 }
 
 const int32_t *
-pcm_resample_32(struct pcm_resample_state *state,
+pcm_resample_fallback_32(struct pcm_resample_state *state,
 			 uint8_t channels,
 			 unsigned src_rate,
-		const int32_t *src_buffer, G_GNUC_UNUSED size_t src_size,
+			 const int32_t *src_buffer,
+			 G_GNUC_UNUSED size_t src_size,
 			 unsigned dest_rate,
 			 size_t *dest_size_r)
 {

src/pcm_resample_internal.h

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2003-2009 The Music Player Daemon Project
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/** \file
+ *
+ * Internal declarations for the pcm_resample library.  The "internal"
+ * resampler is called "fallback" in the MPD source, so the file name
+ * of this header is somewhat unrelated to it.
+ */
+
+#ifndef MPD_PCM_RESAMPLE_INTERNAL_H
+#define MPD_PCM_RESAMPLE_INTERNAL_H
+
+#include "pcm_resample.h"
+#include "config.h"
+
+#ifdef HAVE_LIBSAMPLERATE
+
+void
+pcm_resample_lsr_deinit(struct pcm_resample_state *state);
+
+const int16_t *
+pcm_resample_lsr_16(struct pcm_resample_state *state,
+		    uint8_t channels,
+		    unsigned src_rate,
+		    const int16_t *src_buffer, size_t src_size,
+		    unsigned dest_rate,
+		    size_t *dest_size_r);
+
+const int32_t *
+pcm_resample_lsr_32(struct pcm_resample_state *state,
+		    uint8_t channels,
+		    unsigned src_rate,
+		    const int32_t *src_buffer,
+		    G_GNUC_UNUSED size_t src_size,
+		    unsigned dest_rate,
+		    size_t *dest_size_r);
+
+#else
+
+void
+pcm_resample_fallback_deinit(struct pcm_resample_state *state);
+
+const int16_t *
+pcm_resample_fallback_16(struct pcm_resample_state *state,
+			 uint8_t channels,
+			 unsigned src_rate,
+			 const int16_t *src_buffer, size_t src_size,
+			 unsigned dest_rate,
+			 size_t *dest_size_r);
+
+const int32_t *
+pcm_resample_fallback_32(struct pcm_resample_state *state,
+			 uint8_t channels,
+			 unsigned src_rate,
+			 const int32_t *src_buffer,
+			 G_GNUC_UNUSED size_t src_size,
+			 unsigned dest_rate,
+			 size_t *dest_size_r);
+
+#endif
+
+#endif

src/pcm_resample_libsamplerate.c

@@ -17,7 +17,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#include "pcm_resample.h"
+#include "pcm_resample_internal.h"
 #include "conf.h"
 #include "config.h"
 
@@ -30,7 +30,8 @@
 #undef G_LOG_DOMAIN
 #define G_LOG_DOMAIN "pcm"
 
-void pcm_resample_deinit(struct pcm_resample_state *state)
+void
+pcm_resample_lsr_deinit(struct pcm_resample_state *state)
 {
 	if (state->state != NULL)
 		state->state = src_delete(state->state);
@@ -116,7 +117,7 @@ pcm_resample_set(struct pcm_resample_state *state,
 }
 
 const int16_t *
-pcm_resample_16(struct pcm_resample_state *state,
+pcm_resample_lsr_16(struct pcm_resample_state *state,
 		    uint8_t channels,
 		    unsigned src_rate,
 		    const int16_t *src_buffer, size_t src_size,
@@ -186,7 +187,7 @@ src_float_to_int_array (const float *in, int *out, int len)
 #endif
 
 const int32_t *
-pcm_resample_32(struct pcm_resample_state *state,
+pcm_resample_lsr_32(struct pcm_resample_state *state,
 		    uint8_t channels,
 		    unsigned src_rate,
 		    const int32_t *src_buffer, size_t src_size,