[PATCH alsa-plugins 2/2] samplerate: Support multiple formats

[Takashi Iwai]

Now that ALSA rate plugin core allows each rate plugin dealing with
multiple formats, this patch extends the libsamplerate plugin to
accept more formats, namely, S16 and S32.  The code has been carefully
modified so that it should still be compilable with old alsa-lib.

Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 rate/rate_samplerate.c | 99 +++++++++++++++++++++++++++++++++++-------
 1 file changed, 84 insertions(+), 15 deletions(-)

diff --git a/rate/rate_samplerate.c b/rate/rate_samplerate.c
index 100d6f2b110e..af0bf98cb4e9 100644
--- a/rate/rate_samplerate.c
+++ b/rate/rate_samplerate.c
@@ -40,9 +40,12 @@
 #include <alsa/pcm_rate.h>
 
 struct rate_src {
+	unsigned int version;
 	double ratio;
 	int converter;
 	unsigned int channels;
+	int in_int;
+	int out_int;
 	float *src_buf;
 	float *dst_buf;
 	SRC_STATE *state;
@@ -109,6 +112,13 @@ static int pcm_src_init(void *obj, snd_pcm_rate_info_t *info)
 	rate->data.src_ratio = rate->ratio;
 	rate->data.end_of_input = 0;
 
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+	if (rate->version >= 0x010003) {
+		rate->in_int = info->in.format == SND_PCM_FORMAT_S32;
+		rate->out_int = info->out.format == SND_PCM_FORMAT_S32;
+	}
+#endif
+
 	return 0;
 }
 
@@ -128,24 +138,61 @@ static void pcm_src_reset(void *obj)
 	src_reset(rate->state);
 }
 
-static void pcm_src_convert_s16(void *obj, int16_t *dst, unsigned int dst_frames,
-				const int16_t *src, unsigned int src_frames)
+static void do_convert(struct rate_src *rate,
+		       void *dst, unsigned int dst_frames,
+		       const void *src, unsigned int src_frames)
 {
-	struct rate_src *rate = obj;
 	unsigned int ofs;
 
 	rate->data.input_frames = src_frames;
 	rate->data.output_frames = dst_frames;
 	rate->data.end_of_input = 0;
 	
-	src_short_to_float_array(src, rate->src_buf, src_frames * rate->channels);
+	if (rate->in_int)
+		src_int_to_float_array(src, rate->src_buf, src_frames * rate->channels);
+	else
+		src_short_to_float_array(src, rate->src_buf, src_frames * rate->channels);
 	src_process(rate->state, &rate->data);
 	if (rate->data.output_frames_gen < dst_frames)
 		ofs = dst_frames - rate->data.output_frames_gen;
 	else
 		ofs = 0;
-	src_float_to_short_array(rate->dst_buf, dst + ofs * rate->channels,
-				 rate->data.output_frames_gen * rate->channels);
+	if (rate->out_int)
+		src_float_to_int_array(rate->dst_buf, dst + ofs * rate->channels * 4,
+				       rate->data.output_frames_gen * rate->channels);
+	else
+		src_float_to_short_array(rate->dst_buf, dst + ofs * rate->channels * 2,
+					 rate->data.output_frames_gen * rate->channels);
+}
+
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+static inline void *get_addr(const snd_pcm_channel_area_t *area, snd_pcm_uframes_t offset)
+{
+	return (char *)area->addr + (area->first + area->step * offset) / 8;
+}
+
+static void pcm_src_convert(void *obj,
+			    const snd_pcm_channel_area_t *dst_areas,
+			    snd_pcm_uframes_t dst_offset,
+			    unsigned int dst_frames,
+			    const snd_pcm_channel_area_t *src_areas,
+			    snd_pcm_uframes_t src_offset,
+			    unsigned int src_frames)
+{
+	struct rate_src *rate = obj;
+	const void *src = get_addr(src_areas, src_offset);
+	void *dst = get_addr(dst_areas, dst_offset);
+
+	do_convert(rate, dst, dst_frames, src, src_frames);
+}
+#endif
+
+static void pcm_src_convert_s16(void *obj, int16_t *dst, unsigned int dst_frames,
+				const int16_t *src, unsigned int src_frames)
+{
+	struct rate_src *rate = obj;
+
+	do_convert(rate, dst, dst_frames, src, src_frames);
 }
 
 static void pcm_src_close(void *obj)
@@ -167,12 +214,28 @@ static void dump(void *obj ATTRIBUTE_UNUSED, snd_output_t *out)
 }
 #endif
 
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+static int get_supported_formats(void *obj, uint64_t *in_formats,
+				 uint64_t *out_formats,
+				 unsigned int *flags)
+{
+	*in_formats = *out_formats =
+		(1ULL << SND_PCM_FORMAT_S16) |
+		(1ULL << SND_PCM_FORMAT_S32);
+	*flags = SND_PCM_RATE_FLAG_INTERLEAVED;
+	return 0;
+}
+#endif
+
 static snd_pcm_rate_ops_t pcm_src_ops = {
 	.close = pcm_src_close,
 	.init = pcm_src_init,
 	.free = pcm_src_free,
 	.reset = pcm_src_reset,
 	.adjust_pitch = pcm_src_adjust_pitch,
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+	.convert = pcm_src_convert,
+#endif
 	.convert_s16 = pcm_src_convert_s16,
 	.input_frames = input_frames,
 	.output_frames = output_frames,
@@ -181,6 +244,9 @@ static snd_pcm_rate_ops_t pcm_src_ops = {
 	.get_supported_rates = get_supported_rates,
 	.dump = dump,
 #endif
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+	.get_supported_formats = get_supported_formats,
+#endif
 };
 
 static int pcm_src_open(unsigned int version, void **objp,
@@ -188,24 +254,27 @@ static int pcm_src_open(unsigned int version, void **objp,
 {
 	struct rate_src *rate;
 
-#if SND_PCM_RATE_PLUGIN_VERSION < 0x010002
-	if (version != SND_PCM_RATE_PLUGIN_VERSION) {
-		fprintf(stderr, "Invalid rate plugin version %x\n", version);
-		return -EINVAL;
-	}
-#endif
 	rate = calloc(1, sizeof(*rate));
 	if (! rate)
 		return -ENOMEM;
+
+	rate->version = version;
 	rate->converter = type;
 
 	*objp = rate;
 #if SND_PCM_RATE_PLUGIN_VERSION >= 0x010002
-	if (version == 0x010001)
+	if (version == 0x010001) {
 		memcpy(ops, &pcm_src_ops, sizeof(snd_pcm_rate_old_ops_t));
-	else
+		return 0;
+	}
+#endif
+#if SND_PCM_RATE_PLUGIN_VERSION >= 0x010003
+	if (version == 0x010002) {
+		memcpy(ops, &pcm_src_ops, sizeof(snd_pcm_rate_v2_ops_t));
+		return 0;
+	}
 #endif
-		*ops = pcm_src_ops;
+	*ops = pcm_src_ops;
 	return 0;
 }
 
-- 
2.26.2