pcm_resample: choose the fallback resampler at runtime

Even if libsamplerate support is enabled, compile the fallback
resampler.  When the user specifies the option
"samplerate_converter=internal", it is chosen in favor of
libsamplerate.  This may help users with a weak FPU who don't want to
compile a custom MPD from source, because the fallback resampler does
not use floating point operations.

1 files changed, 33 insertions, 15 deletions

diff --git a/src/pcm_resample.c b/src/pcm_resample.c
index f27bf4f0c..69fda79e4 100644
--- a/src/pcm_resample.c
+++ b/src/pcm_resample.c
@@ -20,15 +20,30 @@
 #include "pcm_resample_internal.h"
 #include "config.h"
 
+#ifdef HAVE_LIBSAMPLERATE
+#include "conf.h"
+#endif
+
 #include <string.h>
 
+#ifdef HAVE_LIBSAMPLERATE
+static bool
+pcm_resample_lsr_enabled(void)
+{
+	return strcmp(config_get_string(CONF_SAMPLERATE_CONVERTER, ""),
+		      "internal") == 0;
+}
+#endif
+
 void pcm_resample_init(struct pcm_resample_state *state)
 {
 	memset(state, 0, sizeof(*state));
 
 #ifdef HAVE_LIBSAMPLERATE
-	pcm_buffer_init(&state->in);
-	pcm_buffer_init(&state->out);
+	if (pcm_resample_lsr_enabled()) {
+		pcm_buffer_init(&state->in);
+		pcm_buffer_init(&state->out);
+	}
 #endif
 
 	pcm_buffer_init(&state->buffer);
@@ -37,10 +52,11 @@ void pcm_resample_init(struct pcm_resample_state *state)
 void pcm_resample_deinit(struct pcm_resample_state *state)
 {
 #ifdef HAVE_LIBSAMPLERATE
-	pcm_resample_lsr_deinit(state);
-#else
-	pcm_resample_fallback_deinit(state);
+	if (pcm_resample_lsr_enabled())
+		pcm_resample_lsr_deinit(state);
+	else
 #endif
+		pcm_resample_fallback_deinit(state);
 }
 
 const int16_t *
@@ -52,14 +68,15 @@ pcm_resample_16(struct pcm_resample_state *state,
 		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
+	if (pcm_resample_lsr_enabled())
+		return pcm_resample_lsr_16(state, channels,
+					   src_rate, src_buffer, src_size,
+					   dest_rate, dest_size_r);
+#endif
+
 	return pcm_resample_fallback_16(state, channels,
 					src_rate, src_buffer, src_size,
 					dest_rate, dest_size_r);
-#endif
 }
 
 const int32_t *
@@ -71,12 +88,13 @@ pcm_resample_32(struct pcm_resample_state *state,
 		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
+	if (pcm_resample_lsr_enabled())
+		return pcm_resample_lsr_32(state, channels,
+					   src_rate, src_buffer, src_size,
+					   dest_rate, dest_size_r);
+#endif
+
 	return pcm_resample_fallback_32(state, channels,
 					src_rate, src_buffer, src_size,
 					dest_rate, dest_size_r);
-#endif
 }