ALSA

Makefile

@@ -12,6 +12,10 @@ endif
 ifeq ($(BUILD_OSS), 1)
    SOURCE += oss.c
 endif
+ifeq ($(BUILD_ALSA), 1)
+   SOURCE += alsa.c
+   LIBS += -lasound
+endif
 
 ifeq ($(BUILD_OPENGL), 1)
    SOURCE += gl.c

alsa.c

@@ -0,0 +1,141 @@
+#include "driver.h"
+#include <stdlib.h>
+#include <alsa/asoundlib.h>
+
+#define TRY_ALSA(x) if ( x < 0 ) { \
+                  goto error; \
+               }
+
+typedef struct alsa
+{
+   snd_pcm_t *pcm;
+} alsa_t;
+
+static void* __alsa_init(const char* device, int rate, int latency)
+{
+   alsa_t *alsa = calloc(1, sizeof(alsa_t));
+   if ( alsa == NULL )
+      return NULL;
+
+   snd_pcm_hw_params_t *params = NULL;
+   snd_pcm_sw_params_t *sw_params = NULL;
+
+   const char *alsa_dev = "default";
+   if ( device != NULL )
+      alsa_dev = device;
+
+   TRY_ALSA(snd_pcm_open(&alsa->pcm, alsa_dev, SND_PCM_STREAM_PLAYBACK, 0));
+
+   unsigned int latency_usec = latency * 1000;
+
+   snd_pcm_format_t format = SND_PCM_FORMAT_S16_LE;
+   unsigned int channels = 2;
+
+   TRY_ALSA(snd_pcm_hw_params_malloc(&params));
+
+   TRY_ALSA(snd_pcm_hw_params_any(alsa->pcm, params));
+   TRY_ALSA(snd_pcm_hw_params_set_access(alsa->pcm, params, SND_PCM_ACCESS_RW_INTERLEAVED));
+   TRY_ALSA(snd_pcm_hw_params_set_format(alsa->pcm, params, format));
+   TRY_ALSA(snd_pcm_hw_params_set_channels(alsa->pcm, params, channels));
+   TRY_ALSA(snd_pcm_hw_params_set_rate(alsa->pcm, params, rate, 0));
+   TRY_ALSA(snd_pcm_hw_params_set_buffer_time_near(alsa->pcm, params, &latency_usec, NULL));
+   latency_usec = latency * 250;
+   TRY_ALSA(snd_pcm_hw_params_set_period_time_near(alsa->pcm, params, &latency_usec, NULL));
+
+   TRY_ALSA(snd_pcm_hw_params(alsa->pcm, params));
+
+   snd_pcm_uframes_t alsa_sizes;
+   snd_pcm_hw_params_get_period_size(params, &alsa_sizes, NULL);
+   fprintf(stderr, "Period size: %d\n", (int)alsa_sizes);
+   snd_pcm_hw_params_get_buffer_size(params, &alsa_sizes);
+   fprintf(stderr, "Buffer size: %d\n", (int)alsa_sizes);
+
+   if (snd_pcm_sw_params_malloc(&sw_params) < 0)
+      goto error;
+
+   TRY_ALSA(snd_pcm_sw_params_current(alsa->pcm, sw_params));
+   TRY_ALSA(snd_pcm_sw_params_set_start_threshold(alsa->pcm, sw_params, alsa_sizes));
+   TRY_ALSA(snd_pcm_sw_params(alsa->pcm, sw_params));
+
+   snd_pcm_sw_params_free(sw_params);
+   snd_pcm_hw_params_free(params);
+
+   return alsa;
+
+error:
+   if ( params != NULL )
+      snd_pcm_hw_params_free(params);
+
+   if ( sw_params != NULL )
+      snd_pcm_sw_params_free(sw_params);
+
+   if ( alsa != NULL )
+   {
+      if ( alsa->pcm != NULL )
+         snd_pcm_close(alsa->pcm);
+
+      free(alsa);
+   }
+   return NULL;
+}
+
+static ssize_t __alsa_write(void* data, const void* buf, size_t size)
+{
+   alsa_t *alsa = data;
+
+   snd_pcm_sframes_t frames;
+   frames = snd_pcm_writei(alsa->pcm, buf, snd_pcm_bytes_to_frames(alsa->pcm, size));
+
+   if ( frames == -EPIPE || frames == -EINTR || frames == -ESTRPIPE )
+   {
+      if ( snd_pcm_recover(alsa->pcm, frames, 1) < 0 )
+         return -1;
+
+      return size;
+   }
+
+   else if ( frames < 0 )
+      return -1;
+
+   return snd_pcm_frames_to_bytes(alsa->pcm, frames);
+}
+
+static bool __alsa_stop(void *data)
+{
+/*   int *fd = data;
+   ioctl(*fd, SNDCTL_DSP_RESET, 0);*/
+   return true;
+}
+
+static bool __alsa_start(void *data)
+{
+   return true;
+}
+
+static void __alsa_free(void *data)
+{
+   alsa_t *alsa = data;
+   if ( alsa )
+   {
+      if ( alsa->pcm )
+      {
+         snd_pcm_drop(alsa->pcm);
+         snd_pcm_close(alsa->pcm);
+      }
+      free(alsa);
+   }
+}
+
+const audio_driver_t audio_alsa = {
+   .init = __alsa_init,
+   .write = __alsa_write,
+   .stop = __alsa_stop,
+   .start = __alsa_start,
+   .free = __alsa_free
+};
+
+   
+
+
+   
+   

config.h

@@ -19,9 +19,10 @@
 #define VIDEO_GL 0
 #define AUDIO_RSOUND 1
 #define AUDIO_OSS 2
+#define AUDIO_ALSA 3
 
 #define VIDEO_DRIVER VIDEO_GL
-#define AUDIO_DRIVER AUDIO_OSS
+#define AUDIO_DRIVER AUDIO_ALSA
 
 static const bool force_aspect = true; // On resize and fullscreen, rendering area will stay 8:7
 

rsound.c

@@ -98,6 +98,7 @@ static void __rsd_free(void *data)
 
    rsd_stop(rsd->rd);
    rsd_free(rsd->rd);
+   free(rsd);
 }
 
 const audio_driver_t audio_rsound = {

ssnes.c

@@ -17,6 +17,7 @@ static SRC_STATE* source = NULL;
 //////////////////////////////////////////////// Backends
 extern const audio_driver_t audio_rsound;
 extern const audio_driver_t audio_oss;
+extern const audio_driver_t audio_alsa;
 extern const video_driver_t video_gl;
 ////////////////////////////////////////////////
 
@@ -28,6 +29,8 @@ static driver_t driver = {
    .audio = &audio_rsound,
 #elif AUDIO_DRIVER == AUDIO_OSS
    .audio = &audio_oss,
+#elif AUDIO_DRIVER == AUDIO_ALSA
+   .audio = &audio_alsa,
 #endif
 };