Audio Plugin: add PulseAudio support

If PulseAudio development libraries are present, Audio
plugin will now support it. It may still fall back to
ALSA if a PulseAudio server is not found at runtime.

PulseAudio backend supports multiple clients using
one audio adapter.

(+ various fixes and style improvements)

Signed-off-by: Manuel Bachmann <manuel.bachmann@iot.bzh>

10 files changed, 693 insertions, 104 deletions

diff --git a/plugins/audio/CMakeLists.txt b/plugins/audio/CMakeLists.txt
index 7fa1f75f..ee858b4c 100644
--- a/plugins/audio/CMakeLists.txt
+++ b/plugins/audio/CMakeLists.txt
@@ -1,6 +1,10 @@
 IF(alsa_FOUND)
 
-  ADD_LIBRARY(audio-api MODULE audio-api.c audio-alsa.c)
+  IF(pulseaudio_FOUND)
+    SET(pulse_sources audio-pulse.c)
+  ENDIF(pulseaudio_FOUND)
+
+  ADD_LIBRARY(audio-api MODULE audio-api.c audio-alsa.c ${pulse_sources})
   SET_TARGET_PROPERTIES(audio-api PROPERTIES PREFIX "")
   TARGET_LINK_LIBRARIES(audio-api ${link_libraries})
   INCLUDE_DIRECTORIES(${include_dirs})
diff --git a/plugins/audio/audio-alsa.c b/plugins/audio/audio-alsa.c
index 51f49702..7310ea89 100644
--- a/plugins/audio/audio-alsa.c
+++ b/plugins/audio/audio-alsa.c
@@ -17,7 +17,6 @@
  */
 
 #include "audio-api.h"
-#include "audio-alsa.h"
 
 snd_mixer_selem_channel_id_t SCHANNELS[8] = {
  SND_MIXER_SCHN_FRONT_LEFT,
@@ -43,7 +42,7 @@ PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
     int num, i;
 
     if (snd_pcm_open (&dev, name, SND_PCM_STREAM_PLAYBACK, 0) < 0)
-        return 0;
+        return -1;
 
     snd_pcm_hw_params_malloc (&params);
     snd_pcm_hw_params_any (dev, params);
@@ -53,14 +52,14 @@ PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
     snd_pcm_hw_params_set_channels (dev, params, ctx->channels);
     if (snd_pcm_hw_params (dev, params) < 0) {
         snd_pcm_hw_params_free (params);
-        return 0;
+        return -1;
     }
     snd_pcm_prepare (dev);
 
     snd_mixer_open (&mixer, 0);
     if (snd_mixer_attach (mixer, name) < 0) {
         snd_pcm_hw_params_free (params);
-        return 0;
+        return -1;
     }
     snd_mixer_selem_register (mixer, NULL, NULL);
     snd_mixer_load (mixer);
@@ -97,33 +96,33 @@ PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
     }
 
     /* allocate the global array if it hasn't been done */
-    if (!dev_ctx) {
-        dev_ctx = (dev_ctx_T**) malloc (sizeof(dev_ctx_T));
-        dev_ctx[0] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
-        dev_ctx[0]->name = NULL;
-        dev_ctx[0]->dev = NULL;
+    if (!dev_ctx_a) {
+        dev_ctx_a = (dev_ctx_alsa_T**) malloc (sizeof(dev_ctx_alsa_T));
+        dev_ctx_a[0] = (dev_ctx_alsa_T*) malloc (sizeof(dev_ctx_alsa_T));
+        dev_ctx_a[0]->name = NULL;
+        dev_ctx_a[0]->dev = NULL;
     }
 
     /* is a card with similar name already opened ? */
-    for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
-        if (dev_ctx[num]->name &&
-           !strcmp (dev_ctx[num]->name, name))
-            return 0;
+    for (num = 0; num < (sizeof(dev_ctx_a)/sizeof(dev_ctx_alsa_T)); num++) {
+        if (dev_ctx_a[num]->name &&
+           !strcmp (dev_ctx_a[num]->name, name))
+            return -1;
     }
     num++;
 
     /* it's not... let us add it to the global array */
-    dev_ctx = (dev_ctx_T**) realloc (dev_ctx, (num+1)*sizeof(dev_ctx_T));
-    dev_ctx[num] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
-    dev_ctx[num]->name = strdup (name);
-    dev_ctx[num]->dev = dev;
-    dev_ctx[num]->params = params;
-    dev_ctx[num]->mixer_elm = mixer_elm;
-    dev_ctx[num]->mixer_elm_m = mixer_elm_m;
-    dev_ctx[num]->vol_max = vol_max;
-    dev_ctx[num]->vol = vol;
-    dev_ctx[num]->thr_should_run = 0;
-    dev_ctx[num]->thr_finished = 0;
+    dev_ctx_a = (dev_ctx_alsa_T**) realloc (dev_ctx_a, (num+1)*sizeof(dev_ctx_alsa_T));
+    dev_ctx_a[num] = (dev_ctx_alsa_T*) malloc (sizeof(dev_ctx_alsa_T));
+    dev_ctx_a[num]->name = strdup (name);
+    dev_ctx_a[num]->dev = dev;
+    dev_ctx_a[num]->params = params;
+    dev_ctx_a[num]->mixer_elm = mixer_elm;
+    dev_ctx_a[num]->mixer_elm_m = mixer_elm_m;
+    dev_ctx_a[num]->vol_max = vol_max;
+    dev_ctx_a[num]->vol = vol;
+    dev_ctx_a[num]->thr_should_run = 0;
+    dev_ctx_a[num]->thr_finished = 0;
 
     /* make the client context aware of current card state */
     for (i = 0; i < 8; i++)
@@ -131,22 +130,22 @@ PUBLIC unsigned char _alsa_init (const char *name, audioCtxHandleT *ctx) {
     ctx->mute = _alsa_get_mute (num);
     ctx->idx = num;
 
-    return 1;
+    return 0;
 }
 
 PUBLIC void _alsa_free (const char *name) {
 
     int num;
 
-    for (num = 0; num < (sizeof(dev_ctx)/sizeof(dev_ctx_T)); num++) {
-        if (dev_ctx[num]->name &&
-           !strcmp (dev_ctx[num]->name, name)) {
-            snd_pcm_close (dev_ctx[num]->dev);
-            snd_pcm_hw_params_free (dev_ctx[num]->params);
-            free (dev_ctx[num]->name);
-            dev_ctx[num]->name = NULL;
-            dev_ctx[num]->dev = NULL;
-            free(dev_ctx[num]);
+    for (num = 0; num < (sizeof(dev_ctx_a)/sizeof(dev_ctx_alsa_T)); num++) {
+        if (dev_ctx_a[num]->name &&
+           !strcmp (dev_ctx_a[num]->name, name)) {
+            snd_pcm_close (dev_ctx_a[num]->dev);
+            snd_pcm_hw_params_free (dev_ctx_a[num]->params);
+            free (dev_ctx_a[num]->name);
+            dev_ctx_a[num]->dev = NULL;
+            dev_ctx_a[num]->name = NULL;
+            free (dev_ctx_a[num]);
             return;
         }
     }
@@ -154,55 +153,55 @@ PUBLIC void _alsa_free (const char *name) {
 
 PUBLIC void _alsa_play (unsigned int num) {
 
-    if (!dev_ctx || !dev_ctx[num] || dev_ctx[num]->thr_should_run ||
+    if (!dev_ctx_a || !dev_ctx_a[num] || dev_ctx_a[num]->thr_should_run ||
         access (AUDIO_BUFFER, F_OK) == -1)
         return;
 
-    dev_ctx[num]->thr_should_run = 1;
-    dev_ctx[num]->thr_finished = 0;
-    pthread_create(&dev_ctx[num]->thr, NULL, _play_thread_fn, (void*)dev_ctx[num]);
+    dev_ctx_a[num]->thr_should_run = 1;
+    dev_ctx_a[num]->thr_finished = 0;
+    pthread_create (&dev_ctx_a[num]->thr, NULL, _alsa_play_thread_fn, (void*)dev_ctx_a[num]);
 }
 
 PUBLIC void _alsa_stop (unsigned int num) {
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->thr_should_run)
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->thr_should_run)
         return;
 
     /* stop the "while" loop in thread */
-    dev_ctx[num]->thr_should_run = 0;
+    dev_ctx_a[num]->thr_should_run = 0;
 
-    while (!dev_ctx[num]->thr_finished)
+    while (!dev_ctx_a[num]->thr_finished)
         usleep(100000);
 
-    pthread_join(dev_ctx[num]->thr, NULL);
+    pthread_join (dev_ctx_a[num]->thr, NULL);
 }
 
 PUBLIC int _alsa_get_volume (unsigned int num, unsigned int channel) {
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm)
         return;
 
-    snd_mixer_selem_get_playback_volume (dev_ctx[num]->mixer_elm, SCHANNELS[channel], &dev_ctx[num]->vol);
+    snd_mixer_selem_get_playback_volume (dev_ctx_a[num]->mixer_elm, SCHANNELS[channel], &dev_ctx_a[num]->vol);
 
-    return (int)(dev_ctx[num]->vol*100)/dev_ctx[num]->vol_max;
+    return (int)(dev_ctx_a[num]->vol*100)/dev_ctx_a[num]->vol_max;
 }
 
 PUBLIC void _alsa_set_volume (unsigned int num, unsigned int channel, int vol) {
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm ||
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm ||
         0 > vol > 100)
         return;
 
-    snd_mixer_selem_set_playback_volume (dev_ctx[num]->mixer_elm, SCHANNELS[channel], (vol*dev_ctx[num]->vol_max)/100);
+    snd_mixer_selem_set_playback_volume (dev_ctx_a[num]->mixer_elm, SCHANNELS[channel], (vol*dev_ctx_a[num]->vol_max)/100);
 
 }
 
 PUBLIC void _alsa_set_volume_all (unsigned int num, int vol) {
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm ||
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm ||
         0 > vol > 100)
 
-    snd_mixer_selem_set_playback_volume_all (dev_ctx[num]->mixer_elm, (vol*dev_ctx[num]->vol_max)/100);
+    snd_mixer_selem_set_playback_volume_all (dev_ctx_a[num]->mixer_elm, (vol*dev_ctx_a[num]->vol_max)/100);
 }
 
 PUBLIC unsigned char _alsa_get_mute (unsigned int num) {
@@ -210,18 +209,18 @@ PUBLIC unsigned char _alsa_get_mute (unsigned int num) {
     int mute = 0;
     snd_mixer_elem_t *elm_m;
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm)
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm)
         return;
 
-    dev_ctx[num]->mixer_elm_m ? (elm_m = dev_ctx[num]->mixer_elm_m) :
-                                (elm_m = dev_ctx[num]->mixer_elm);
+    dev_ctx_a[num]->mixer_elm_m ? (elm_m = dev_ctx_a[num]->mixer_elm_m) :
+                                  (elm_m = dev_ctx_a[num]->mixer_elm);
 
     if (snd_mixer_selem_has_playback_switch (elm_m)) {
         snd_mixer_selem_get_playback_switch (elm_m, SND_MIXER_SCHN_FRONT_LEFT, &mute);
         snd_mixer_selem_get_playback_switch (elm_m, SND_MIXER_SCHN_FRONT_RIGHT, &mute);
     }
 
-    if (dev_ctx[num]->mixer_elm_m)
+    if (dev_ctx_a[num]->mixer_elm_m)
         return (unsigned char)mute;
     else
         return (unsigned char)!mute;
@@ -232,14 +231,14 @@ PUBLIC void _alsa_set_mute (unsigned int num, unsigned char tomute) {
     snd_mixer_elem_t *elm_m;
     int mute;
 
-    if (!dev_ctx || !dev_ctx[num] || !dev_ctx[num]->mixer_elm || 1 < tomute < 0)
+    if (!dev_ctx_a || !dev_ctx_a[num] || !dev_ctx_a[num]->mixer_elm || 1 < tomute < 0)
         return;
 
-    if (dev_ctx[num]->mixer_elm_m) {
-        elm_m = dev_ctx[num]->mixer_elm_m;
+    if (dev_ctx_a[num]->mixer_elm_m) {
+        elm_m = dev_ctx_a[num]->mixer_elm_m;
         mute = (int)!tomute;
     } else {
-        elm_m = dev_ctx[num]->mixer_elm;
+        elm_m = dev_ctx_a[num]->mixer_elm;
         mute = (int)tomute;
     }
 
@@ -249,25 +248,25 @@ PUBLIC void _alsa_set_mute (unsigned int num, unsigned char tomute) {
 
 PUBLIC void _alsa_set_rate (unsigned int num, unsigned int rate) {
 
-    if (!dev_ctx || !dev_ctx[num])
+    if (!dev_ctx_a || !dev_ctx_a[num])
         return;
 
-    snd_pcm_hw_params_set_rate_near (dev_ctx[num]->dev, dev_ctx[num]->params, &rate, 0);
+    snd_pcm_hw_params_set_rate_near (dev_ctx_a[num]->dev, dev_ctx_a[num]->params, &rate, 0);
 }
 
 PUBLIC void _alsa_set_channels (unsigned int num, unsigned int channels) {
 
-    if (!dev_ctx || !dev_ctx[num])
+    if (!dev_ctx_a || !dev_ctx_a[num])
         return;
 
-    snd_pcm_hw_params_set_channels (dev_ctx[num]->dev, dev_ctx[num]->params, channels);
+    snd_pcm_hw_params_set_channels (dev_ctx_a[num]->dev, dev_ctx_a[num]->params, channels);
 }
 
  /* ---- LOCAL THREADED FUNCTIONS ---- */
 
-STATIC void* _play_thread_fn (void *ctx) {
+STATIC void* _alsa_play_thread_fn (void *ctx) {
 
-    dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
+    dev_ctx_alsa_T *dev_ctx_a = (dev_ctx_alsa_T *)ctx;
     FILE *file = NULL;
     char *buf = NULL;
     long size;
@@ -275,7 +274,7 @@ STATIC void* _play_thread_fn (void *ctx) {
 
     file = fopen (AUDIO_BUFFER, "rb");
 
-    while (dev_ctx->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
+    while (dev_ctx_a->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
         fseek (file, 0, SEEK_END);
         size = ftell (file);
         buf = (char*) realloc (buf, size * sizeof(char));
@@ -285,15 +284,15 @@ STATIC void* _play_thread_fn (void *ctx) {
         fread (buf, 1, size, file);
         fflush (file);
 
-        if ((res = snd_pcm_writei (dev_ctx->dev, buf, frames)) != frames) {
-            snd_pcm_recover (dev_ctx->dev, res, 0);
-            snd_pcm_prepare (dev_ctx->dev);
+        if ((res = snd_pcm_writei (dev_ctx_a->dev, buf, frames)) != frames) {
+            snd_pcm_recover (dev_ctx_a->dev, res, 0);
+            snd_pcm_prepare (dev_ctx_a->dev);
         }
         /* snd_pcm_drain (dev_ctx->dev); */
     }
     if (buf) free(buf);
     if (file) fclose(file);
 
-    dev_ctx->thr_finished = 1;
+    dev_ctx_a->thr_finished = 1;
     return 0;
 }
diff --git a/plugins/audio/audio-alsa.h b/plugins/audio/audio-alsa.h
index 25292ad1..9b9ee21c 100644
--- a/plugins/audio/audio-alsa.h
+++ b/plugins/audio/audio-alsa.h
@@ -24,9 +24,9 @@
 
 #include "local-def.h"
 
-typedef struct dev_ctx dev_ctx_T;
+typedef struct dev_ctx_alsa dev_ctx_alsa_T;
 
-struct dev_ctx {
+struct dev_ctx_alsa {
   char *name;
   snd_pcm_t *dev;
   snd_pcm_hw_params_t *params;
@@ -39,10 +39,10 @@ struct dev_ctx {
   unsigned char thr_finished;
 };
 
-STATIC void* _play_thread_fn (void *);
+STATIC void* _alsa_play_thread_fn (void *);
 PUBLIC int _alsa_get_volume (unsigned int, unsigned int);
 PUBLIC unsigned char _alsa_get_mute (unsigned int);
 
-static struct dev_ctx **dev_ctx = NULL;
+static struct dev_ctx_alsa **dev_ctx_a = NULL;
 
 #endif /* AUDIO_ALSA_H */
diff --git a/plugins/audio/audio-api.c b/plugins/audio/audio-api.c
index 8350377d..4a8d0da1 100644
--- a/plugins/audio/audio-api.c
+++ b/plugins/audio/audio-api.c
@@ -17,8 +17,88 @@
  */
 
 #include "audio-api.h"
-#include "audio-alsa.h"
 
+/* ------ BACKEND FUNCTIONS ------- */
+
+void _backend_init (const char *name, audioCtxHandleT *ctx) {
+
+# ifdef HAVE_PULSE
+    if (_pulse_init (name, ctx) < 0)
+# endif
+    _alsa_init (name, ctx);
+}
+
+void _backend_free (audioCtxHandleT *ctx) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_free (ctx); else
+# endif
+    _alsa_free (ctx->idx);
+}
+
+void _backend_play (audioCtxHandleT *ctx) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_play (ctx); else
+# endif
+    _alsa_play (ctx->idx);
+}
+
+void _backend_stop (audioCtxHandleT *ctx) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_stop (ctx); else
+# endif
+    _alsa_stop (ctx->idx);
+}
+
+int _backend_get_volume (audioCtxHandleT *ctx, unsigned int channel) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) return _pulse_get_volume (ctx, channel); else
+# endif
+    return _alsa_get_volume (ctx->idx, channel);
+}
+
+void _backend_set_volume (audioCtxHandleT *ctx, unsigned int channel, int vol) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_set_volume (ctx, channel, vol); else
+# endif
+    _alsa_set_volume (ctx->idx, channel, vol);
+}
+
+void _backend_set_volume_all (audioCtxHandleT *ctx, int vol) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_set_volume_all (ctx, vol); else
+# endif
+    _alsa_set_volume_all (ctx->idx, vol);
+}
+
+unsigned char _backend_get_mute (audioCtxHandleT *ctx) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) return _pulse_get_mute (ctx); else
+# endif
+    return _alsa_get_mute (ctx->idx);
+}
+
+void _backend_set_mute (audioCtxHandleT *ctx, unsigned char mute) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) _pulse_set_mute (ctx, mute); else
+# endif
+    _alsa_set_mute (ctx->idx, mute);
+}
+
+void _backend_set_channels (audioCtxHandleT *ctx, unsigned int channels) {
+
+# ifdef HAVE_PULSE
+    if (ctx->audio_dev) return; else
+# endif
+    _alsa_set_channels (ctx->idx, channels);
+}
 
 /* ------ LOCAL HELPER FUNCTIONS --------- */
 
@@ -29,6 +109,7 @@ STATIC audioCtxHandleT* initAudioCtx () {
     int i;
 
     ctx = malloc (sizeof(audioCtxHandleT));
+    ctx->audio_dev = NULL;
     ctx->idx = -1;
     for (i = 0; i < 8; i++)
         ctx->volume[i] = 25;
@@ -42,7 +123,7 @@ STATIC audioCtxHandleT* initAudioCtx () {
 STATIC AFB_error releaseAudio (audioCtxHandleT *ctx) {
 
     /* power it off */
-    _alsa_free (ctx->idx);
+    _backend_free (ctx);
 
     /* clean client context */
     ctx->idx = -1;
@@ -66,9 +147,9 @@ STATIC json_object* init (AFB_request *request) {        /* AFB_SESSION_CHECK */
     /* create a private client context */
     if (!request->context)
         request->context = initAudioCtx();
-    
-    _alsa_init("default", request->context);
-    
+
+    _backend_init("default", request->context);
+
     jresp = json_object_new_object();
     json_object_object_add (jresp, "info", json_object_new_string ("Audio initialised"));
     return (jresp);
@@ -87,7 +168,7 @@ STATIC json_object* volume (AFB_request *request) {      /* AFB_SESSION_CHECK */
     /* no "?value=" parameter : return current state */
     if (!value) {
         for (i = 0; i < 8; i++) {
-            ctx->volume[i] = _alsa_get_volume (ctx->idx, i);
+            ctx->volume[i] = _backend_get_volume (ctx, i);
             snprintf (volume_str+len_str, sizeof(volume_str)-len_str, "%d,", ctx->volume[i]);
             len_str = strlen(volume_str);
         }
@@ -107,19 +188,19 @@ STATIC json_object* volume (AFB_request *request) {      /* AFB_SESSION_CHECK */
             return (jsonNewMessage (AFB_FAIL, "Volume must be between 0 and 100"));
         }
         ctx->volume[0] = volume[0];
-        _alsa_set_volume (ctx->idx, 0, ctx->volume[0]);
+        _backend_set_volume (ctx, 0, ctx->volume[0]);
         snprintf (volume_str, sizeof(volume_str), "%d,", ctx->volume[0]);
 
         for (i = 1; i < 8; i++) {
             volume_i = strtok (NULL, ",");
             /* if there is only one value, set all channels to this one */
             if (!volume_i && i == 1)
-               _alsa_set_volume_all (ctx->idx, ctx->volume[0]);
+               _backend_set_volume_all (ctx, ctx->volume[0]);
             if (!volume_i || 100 < atoi(volume_i) < 0) {
-               ctx->volume[i] = _alsa_get_volume (ctx->idx, i);
+               ctx->volume[i] = _backend_get_volume (ctx, i);
             } else {
                ctx->volume[i] = atoi(volume_i);
-               _alsa_set_volume (ctx->idx, i, ctx->volume[i]);
+               _backend_set_volume (ctx, i, ctx->volume[i]);
             }
             len_str = strlen(volume_str);
             snprintf (volume_str+len_str, sizeof(volume_str)-len_str, "%d,", ctx->volume[i]);
@@ -147,7 +228,7 @@ STATIC json_object* channels (AFB_request *request) {    /* AFB_SESSION_CHECK */
     /* "?value=" parameter, set channels */
     else {
         ctx->channels = atoi (value);
-        _alsa_set_channels (ctx->idx, ctx->channels);
+        _backend_set_channels (ctx, ctx->channels);
 
         snprintf (channels_str, sizeof(channels_str), "%d", ctx->channels);
         json_object_object_add (jresp, "channels", json_object_new_string (channels_str));
@@ -164,7 +245,7 @@ STATIC json_object* mute (AFB_request *request) {        /* AFB_SESSION_CHECK */
 
     /* no "?value=" parameter : return current state */
     if (!value) {
-        ctx->mute = _alsa_get_mute (ctx->idx);
+        ctx->mute = _backend_get_mute (ctx);
         ctx->mute ?
             json_object_object_add (jresp, "mute", json_object_new_string ("on"))
           : json_object_object_add (jresp, "mute", json_object_new_string ("off"));
@@ -173,7 +254,7 @@ STATIC json_object* mute (AFB_request *request) {        /* AFB_SESSION_CHECK */
     /* "?value=" parameter is "1" or "true" */
     else if ( atoi(value) == 1 || !strcasecmp(value, "true") ) {
         ctx->mute = 1;
-        _alsa_set_mute (ctx->idx, ctx->mute);
+        _backend_set_mute (ctx, ctx->mute);
 
         json_object_object_add (jresp, "mute", json_object_new_string ("on"));
     }
@@ -181,7 +262,7 @@ STATIC json_object* mute (AFB_request *request) {        /* AFB_SESSION_CHECK */
     /* "?value=" parameter is "0" or "false" */
     else if ( atoi(value) == 0 || !strcasecmp(value, "false") ) {
         ctx->mute = 0;
-        _alsa_set_mute (ctx->idx, ctx->mute);
+        _backend_set_mute (ctx, ctx->mute);
 
         json_object_object_add (jresp, "mute", json_object_new_string ("off"));
     }
@@ -205,7 +286,7 @@ STATIC json_object* play (AFB_request *request) {        /* AFB_SESSION_CHECK */
     /* "?value=" parameter is "1" or "true" */
     else if ( atoi(value) == 1 || !strcasecmp(value, "true") ) {
         ctx->is_playing = 1;
-        _alsa_play (ctx->idx);
+        _backend_play (ctx);
 
         json_object_object_add (jresp, "play", json_object_new_string ("on"));
     }
@@ -213,7 +294,7 @@ STATIC json_object* play (AFB_request *request) {        /* AFB_SESSION_CHECK */
     /* "?value=" parameter is "0" or "false" */
     else if ( atoi(value) == 0 || !strcasecmp(value, "false") ) {
         ctx->is_playing = 0;
-        _alsa_stop (ctx->idx);
+        _backend_stop (ctx);
 
         json_object_object_add (jresp, "play", json_object_new_string ("off"));
     }
diff --git a/plugins/audio/audio-api.h b/plugins/audio/audio-api.h
index b6669ec9..77d6e152 100644
--- a/plugins/audio/audio-api.h
+++ b/plugins/audio/audio-api.h
@@ -20,26 +20,23 @@
 #define AUDIO_API_H
 
 #include "audio-alsa.h"
+#ifdef HAVE_PULSE
+#include "audio-pulse.h"
+#endif
 
 /* global plugin handle, should store everything we may need */
 typedef struct {
   int devCount;
 } pluginHandleT;
-  
-/* structure holding one audio card with current usage status */
-typedef struct {
-   char *name;
-   void *handle;           /* handle to implementation (ALSA, PulseAudio...) */
- } audioDevT;
 
 /* private client context [will be destroyed when client leaves] */
 typedef struct {
-  audioDevT *radio;         /* pointer to client audio card          */
-  int idx;                  /* audio card index within global array  */
-  int volume[8];            /* audio volume (8 channels) : 0-100     */
-  unsigned int channels;    /* audio channels : 1(mono)/2(stereo)... */
-  unsigned char mute;       /* audio muted : 0(false)/1(true)        */
-  unsigned char is_playing; /* audio is playing: 0(false)/1(true)    */
+  void *audio_dev;          /* handle to implementation (ALSA, PulseAudio...) */
+  int idx;                  /* audio card index within global array           */
+  int volume[8];            /* audio volume (8 channels) : 0-100              */
+  unsigned int channels;    /* audio channels : 1(mono)/2(stereo)...          */
+  unsigned char mute;       /* audio muted : 0(false)/1(true)                 */
+  unsigned char is_playing; /* audio is playing: 0(false)/1(true)             */
 } audioCtxHandleT;
 
 
diff --git a/plugins/audio/audio-pulse.c b/plugins/audio/audio-pulse.c
new file mode 100644
index 00000000..4caf3db5
--- /dev/null
+++ b/plugins/audio/audio-pulse.c
@@ -0,0 +1,448 @@
+/*
+ * Copyright (C) 2016 "IoT.bzh"
+ * Author "Manuel Bachmann"
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "audio-api.h"
+#include "audio-pulse.h"
+
+PUBLIC unsigned char _pulse_init (const char *name, audioCtxHandleT *ctx) {
+
+    pa_mainloop *pa_loop;
+    pa_mainloop_api *pa_api;
+    pa_context *pa_context;
+    pa_simple *pa;
+    pa_sample_spec *pa_spec;
+    struct timeval tv_start, tv_now;
+    int ret, error, i;
+
+    pa_loop = pa_mainloop_new ();
+    pa_api = pa_mainloop_get_api (pa_loop);
+    pa_context = pa_context_new (pa_api, "afb-audio-plugin");
+
+    /* allocate the global array if it hasn't been done */
+    if (!dev_ctx_p)
+        dev_ctx_p = (dev_ctx_pulse_T**) malloc (sizeof(dev_ctx_pulse_T));
+
+    /* create a temporary device, to be held until sink gets discovered */
+    dev_ctx_pulse_T *dev_ctx_p_t = (dev_ctx_pulse_T*) malloc (sizeof(dev_ctx_pulse_T));
+    dev_ctx_p_t->sink_name = NULL;
+    dev_ctx_p_t->card_name = (char**) malloc (sizeof(char*));
+    dev_ctx_p_t->card_name[0] = strdup (name);
+    dev_ctx_p_t->pa_loop = pa_loop;
+    dev_ctx_p_t->pa_context = pa_context;
+
+    pa_context_set_state_callback (pa_context, _pulse_context_cb, (void*)dev_ctx_p_t);
+    pa_context_connect (pa_context, NULL, 0, NULL);
+
+    /* 1 second should be sufficient to retrieve sink info */
+    gettimeofday (&tv_start, NULL);
+    gettimeofday (&tv_now, NULL);
+    while (tv_now.tv_sec - tv_start.tv_sec <= 1) {
+        pa_mainloop_iterate (pa_loop, 0, &ret);
+
+        if (ret == -1) {
+            if (verbose) fprintf (stderr, "Stopping PulseAudio backend...\n");
+            return -1;
+        }
+        if (ret >= 0) {
+            /* found a matching sink from callback */
+            if (verbose) fprintf (stderr, "Success : using sink n.%d\n", error);
+            ctx->audio_dev = (void*)dev_ctx_p[ret];
+            break;
+        }
+        gettimeofday (&tv_now, NULL);
+    }
+    /* fail if we found no matching sink */
+    if (!ctx->audio_dev)
+      return -1;
+
+    /* make the client context aware of current card state */
+    ctx->mute = (unsigned char)dev_ctx_p[ret]->mute;
+    ctx->channels = (unsigned int)dev_ctx_p[ret]->volume.channels;
+    for (i = 0; i < ctx->channels; i++)
+        ctx->volume[i] = (int)dev_ctx_p[ret]->volume.values[i];
+    ctx->idx = ret;
+
+    /* open matching sink for playback */
+    pa_spec = (pa_sample_spec*) malloc (sizeof(pa_sample_spec));
+    pa_spec->format = PA_SAMPLE_S16LE;
+    pa_spec->rate = 22050;
+    pa_spec->channels = ctx->channels;
+
+    if (!(pa = pa_simple_new (NULL, "afb-audio-plugin", PA_STREAM_PLAYBACK, dev_ctx_p[ret]->sink_name,
+                              "afb-audio-output", pa_spec, NULL, NULL, &error))) {
+        fprintf (stderr, "Error opening PulseAudio sink %s : %s\n",
+                          dev_ctx_p[ret]->sink_name, pa_strerror(error));
+        return -1;
+    }
+    dev_ctx_p[ret]->pa = pa;
+    free (pa_spec);
+
+    client_count++;
+
+    return 0;
+}
+
+PUBLIC void _pulse_free (audioCtxHandleT *ctx) {
+
+    int num, i;
+
+    client_count--;
+    if (client_count > 0) return;
+
+    for (num = 0; num < (sizeof(dev_ctx_p)/sizeof(dev_ctx_pulse_T)); num++) {
+
+         for (i = 0; num < (sizeof(dev_ctx_p[num]->card_name)/sizeof(char*)); i++) {
+             free (dev_ctx_p[num]->card_name[i]);
+             dev_ctx_p[num]->card_name[i] = NULL;
+         }
+         pa_context_disconnect (dev_ctx_p[num]->pa_context);
+         pa_context_unref (dev_ctx_p[num]->pa_context);
+         pa_mainloop_free (dev_ctx_p[num]->pa_loop);
+         pa_simple_free (dev_ctx_p[num]->pa);
+         free (dev_ctx_p[num]->sink_name);
+         dev_ctx_p[num]->pa_context = NULL;
+         dev_ctx_p[num]->pa_loop = NULL;
+         dev_ctx_p[num]->pa = NULL;
+         dev_ctx_p[num]->sink_name = NULL;
+         free (dev_ctx_p[num]);
+    }
+}
+
+PUBLIC void _pulse_play (audioCtxHandleT *ctx) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+
+    if (!dev_ctx_p_c || dev_ctx_p_c->thr_should_run || access (AUDIO_BUFFER, F_OK) == -1)
+        return;
+
+    dev_ctx_p_c->thr_should_run = 1;
+    dev_ctx_p_c->thr_finished = 0;
+    pthread_create (&dev_ctx_p_c->thr, NULL, _pulse_play_thread_fn, (void*)dev_ctx_p_c);
+}
+
+PUBLIC void _pulse_stop (audioCtxHandleT *ctx) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+
+    if (!dev_ctx_p_c || !dev_ctx_p_c->thr_should_run)
+        return;
+
+    dev_ctx_p_c->thr_should_run = 0;
+    while (!dev_ctx_p_c->thr_finished)
+        usleep(100000);
+    pthread_join (dev_ctx_p_c->thr, NULL);
+}
+
+PUBLIC int _pulse_get_volume (audioCtxHandleT *ctx, unsigned int channel) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+
+    if (!dev_ctx_p_c)
+        return;
+
+    _pulse_refresh_sink (dev_ctx_p_c);
+
+    return (int)dev_ctx_p_c->volume.values[channel];
+}
+
+PUBLIC void _pulse_set_volume (audioCtxHandleT *ctx, unsigned int channel, int vol) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+    struct pa_cvolume volume;
+
+    if (!dev_ctx_p_c)
+        return;
+
+    volume = dev_ctx_p_c->volume;
+    volume.values[channel] = vol;
+
+    pa_context_set_sink_volume_by_name (dev_ctx_p_c->pa_context, dev_ctx_p_c->sink_name,
+                                        &volume, NULL, NULL);
+    _pulse_refresh_sink (dev_ctx_p_c);
+}
+
+PUBLIC void _pulse_set_volume_all (audioCtxHandleT *ctx, int vol) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+    struct pa_cvolume volume;
+
+    if (!dev_ctx_p_c)
+        return;
+
+    pa_cvolume_init (&volume);
+    pa_cvolume_set (&volume, dev_ctx_p_c->volume.channels, vol);
+
+    pa_context_set_sink_volume_by_name (dev_ctx_p_c->pa_context, dev_ctx_p_c->sink_name,
+                                        &volume, NULL, NULL);
+    _pulse_refresh_sink (dev_ctx_p_c);
+}
+
+PUBLIC unsigned char _pulse_get_mute (audioCtxHandleT *ctx) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+
+    if (!dev_ctx_p_c)
+        return;
+
+    _pulse_refresh_sink (dev_ctx_p_c);
+
+    return (unsigned char)dev_ctx_p_c->mute;
+}
+
+PUBLIC void _pulse_set_mute (audioCtxHandleT *ctx, unsigned char mute) {
+
+    dev_ctx_pulse_T* dev_ctx_p_c = (dev_ctx_pulse_T*)ctx->audio_dev;
+
+    if (!dev_ctx_p_c)
+        return;
+
+    pa_context_set_sink_mute_by_name (dev_ctx_p_c->pa_context, dev_ctx_p_c->sink_name,
+                                      (int)mute, NULL, NULL);
+    _pulse_refresh_sink (dev_ctx_p_c);
+}
+
+ /* ---- LOCAL HELPER FUNCTIONS ---- */
+
+void _pulse_refresh_sink (dev_ctx_pulse_T* dev_ctx_p_c) {
+
+    dev_ctx_p_c->refresh = 1;
+
+    pa_context_get_sink_info_by_name (dev_ctx_p_c->pa_context, dev_ctx_p_c->sink_name,
+                                      _pulse_sink_info_cb, (void*)dev_ctx_p_c);
+
+    while (dev_ctx_p_c->refresh)
+        pa_mainloop_iterate (dev_ctx_p_c->pa_loop, 0, NULL);
+}
+
+void _pulse_enumerate_cards () {
+
+    void **cards, **card;
+    char *name, *found, *alsa_name, *card_name;
+    int new_info, i, num = 0;
+
+    /* allocate the global alsa array */
+    alsa_info = (alsa_info_T**) malloc (sizeof(alsa_info_T));
+    alsa_info[0] = (alsa_info_T*) malloc (sizeof(alsa_info_T));
+    alsa_info[0]->device = NULL;
+    alsa_info[0]->synonyms = NULL;
+
+    /* we use ALSA to enumerate cards */
+    snd_device_name_hint (-1, "pcm", &cards);
+    card = cards;
+
+    for (; *card != NULL; card++) {
+        name = snd_device_name_get_hint (*card, "NAME");
+        new_info = 1;
+
+        /* alsa name is before ':' (if ':' misses, then it has no card) */
+        found = strstr (name, ":");
+        if (!found) continue;
+        /* */
+        alsa_name = (char*) malloc (found-name+1);
+        strncpy (alsa_name, name, found-name);
+        alsa_name[found-name] = '\0';
+
+        /* card name is the invariant between "CARD=" and ',' */
+        found = strstr (name, "CARD=");
+        if (!found) continue;
+        /* */
+        found += 5;
+        card_name = strdup (found);
+        found = strstr (card_name, ",");
+        if (found) card_name[found-card_name] = '\0';
+
+        /* was the card name already listed in the global alsa array ? */
+        for (i = 0; i < (sizeof(alsa_info)/sizeof(alsa_info_T)); i++) {
+
+            if (alsa_info[i]->device &&
+                !strcmp (alsa_info[i]->device, card_name)) {
+                /* it was ; add the alsa name as a new synonym */
+                asprintf (&alsa_info[i]->synonyms, "%s:%s", alsa_info[i]->synonyms, alsa_name);
+                new_info = 0;
+                break;
+            }            
+        }
+        /* it was not ; create it */
+        if (new_info) {
+            alsa_info = (alsa_info_T**) realloc (alsa_info, (num+1)*sizeof(alsa_info_T));
+            alsa_info[num]->device = strdup (card_name);
+            asprintf (&alsa_info[num]->synonyms, ":%s", alsa_name);
+            num++;
+        }
+        free (alsa_name);
+        free (card_name);
+    }
+}
+
+char** _pulse_find_cards (const char *name) {
+
+    char **cards = NULL;
+    char *needle, *found, *next;
+    int num, i = 0;
+
+    if (!alsa_info)
+      _pulse_enumerate_cards ();
+
+    asprintf (&needle, ":%s", name);
+
+    for (num = 0; num < (sizeof(alsa_info)/sizeof(alsa_info_T)); num++) {
+
+        found = strstr (alsa_info[num]->synonyms, needle);
+        while (found) {
+            /* if next character is not ':' or '\0', we are wrong */
+            if ((found[strlen(name)] != ':') && (found[strlen(name)] != '\0')) {
+                found = strstr (found+1, needle);
+                continue;
+            }
+            /* found it ; now return all the "synonym" cards */
+            found = strstr (alsa_info[num]->synonyms, ":");
+            while (found) {
+                next = strstr (found+1, ":");
+                cards = (char**) realloc (cards, (i+1)*sizeof(char*));
+                cards[i] = (char*) malloc (next-found+1);
+                strncpy (cards[i], found+1, next-found);
+                cards[i][next-found] = '\0';
+                i++;
+            }
+        }
+    }
+    free (needle);
+
+    return cards;
+}
+
+ /* ---- LOCAL CALLBACK FUNCTIONS ---- */
+
+STATIC void _pulse_context_cb (pa_context *context, void *data) {
+
+    pa_context_state_t state = pa_context_get_state (context);
+    dev_ctx_pulse_T *dev_ctx_p_t = (dev_ctx_pulse_T *)data;
+
+    if (state == PA_CONTEXT_FAILED) {
+        fprintf (stderr, "Could not connect to PulseAudio !\n");
+        pa_mainloop_quit (dev_ctx_p_t->pa_loop, -1);
+    }
+
+    if (state == PA_CONTEXT_READY)
+        pa_context_get_sink_info_list (context, _pulse_sink_list_cb, (void*)dev_ctx_p_t);
+}
+
+STATIC void _pulse_sink_list_cb (pa_context *context, const pa_sink_info *info,
+				 int eol, void *data) {
+
+    dev_ctx_pulse_T *dev_ctx_p_t = (dev_ctx_pulse_T *)data;
+    const char *device_string;
+    char **cards;
+    int num, i;
+
+    if (eol != 0)
+        return;
+
+    /* ignore sinks with no cards */
+    if (!pa_proplist_contains (info->proplist, "device.string"))
+        return;
+
+    device_string = pa_proplist_gets (info->proplist, "device.string");
+
+    /* was a sink with similar name already found ? */
+    for (num = 0; num < (sizeof(dev_ctx_p)/sizeof(dev_ctx_pulse_T)); num++) {
+        if (dev_ctx_p[num]->sink_name &&
+           !strcmp (dev_ctx_p[num]->sink_name, info->name)) {
+
+            /* yet it was, did it have the required card ? */
+            cards = dev_ctx_p[num]->card_name;
+            for (i = 0; i < (sizeof(cards)/sizeof(char*)); i++) {
+                if (!strcmp (cards[i], dev_ctx_p_t->card_name[0])) {
+                    /* it did : stop there and succeed */
+                    if (verbose) fprintf (stderr, "Found matching sink : %s\n", info->name);
+                    pa_mainloop_quit (dev_ctx_p_t->pa_loop, num);
+                }
+            }
+            /* it did not, ignore and return */
+            return;
+        }
+    }
+    num++;
+
+    /* new sink, find all the cards it manages, fail if none */
+    cards = _pulse_find_cards (device_string);
+    if (!cards) return;
+
+    /* everything is well, register it in global array */
+    dev_ctx_p_t->sink_name = strdup (info->name);
+    dev_ctx_p_t->card_name = cards;
+    dev_ctx_p_t->mute = info->mute;
+    dev_ctx_p_t->volume = info->volume;
+    dev_ctx_p_t->thr_should_run = 0;
+    dev_ctx_p_t->thr_finished = 0;
+    dev_ctx_p[num] = dev_ctx_p_t;
+
+    /* does this new sink have the card we are looking for ? */ /* TODO : factorize this */
+    for (i = 0; i < (sizeof(cards)/sizeof(char*)); i++) {
+        if (!strcmp (cards[i], dev_ctx_p_t->card_name[0])) {
+             /* it did : stop there and succeed */
+             if (verbose) fprintf (stderr, "Found matching sink : %s\n", info->name);
+             pa_mainloop_quit (dev_ctx_p_t->pa_loop, num);
+        }
+    }
+}
+
+STATIC void _pulse_sink_info_cb (pa_context *context, const pa_sink_info *info,
+				 int eol, void *data) {
+
+    dev_ctx_pulse_T *dev_ctx_p_c = (dev_ctx_pulse_T *)data;
+
+    if (eol != 0)
+        return;
+
+    dev_ctx_p_c->refresh = 0;
+    dev_ctx_p_c->mute = info->mute;
+    dev_ctx_p_c->volume = info->volume;
+}
+
+ /* ---- LOCAL THREADED FUNCTIONS ---- */
+
+STATIC void* _pulse_play_thread_fn (void *ctx) {
+
+    dev_ctx_pulse_T *dev_ctx_p_c = (dev_ctx_pulse_T *)ctx;
+    FILE *file = NULL;
+    char *buf = NULL;
+    long size;
+    int error;
+
+    file = fopen (AUDIO_BUFFER, "rb");
+
+    while (dev_ctx_p_c->thr_should_run && file && (access (AUDIO_BUFFER, F_OK) != -1) ) {
+        fseek (file, 0, SEEK_END);
+        size = ftell (file);
+        buf = (char*) realloc (buf, size * sizeof(char));
+
+        fseek (file, 0, SEEK_SET);
+        fread (buf, 1, size, file);
+        fflush (file);
+
+        if (pa_simple_write (dev_ctx_p_c->pa, buf, size*2, &error) < 0)
+            fprintf (stderr, "Error writing to PulseAudio : %s\n", pa_strerror (error));
+        /* pa_simple_drain (dev_ctx_p_c->pa); */
+    }
+    if (buf) free(buf);
+    if (file) fclose(file);
+
+    dev_ctx_p_c->thr_finished = 1;
+    return 0;
+}
diff --git a/plugins/audio/audio-pulse.h b/plugins/audio/audio-pulse.h
new file mode 100644
index 00000000..fc18d9c0
--- /dev/null
+++ b/plugins/audio/audio-pulse.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2016 "IoT.bzh"
+ * Author "Manuel Bachmann"
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef AUDIO_PULSE_H
+#define AUDIO_PULSE_H
+
+#include <sys/time.h>
+#include <pulse/pulseaudio.h>
+#include <pulse/simple.h>
+#include <pulse/error.h>
+
+#include "audio-alsa.h"
+#include "local-def.h"
+
+typedef struct dev_ctx_pulse dev_ctx_pulse_T;
+typedef struct alsa_info alsa_info_T;
+
+struct dev_ctx_pulse {
+  char *sink_name;
+  char **card_name;
+  pa_mainloop *pa_loop;
+  pa_context *pa_context;
+  pa_simple *pa;
+  pa_cvolume volume;
+  int mute;
+  unsigned char refresh;
+  pthread_t thr;
+  unsigned char thr_should_run;
+  unsigned char thr_finished;
+};
+
+struct alsa_info {
+  char *device;
+  char *synonyms;
+};
+
+STATIC void  _pulse_context_cb (pa_context *, void *);
+STATIC void  _pulse_sink_list_cb (pa_context *, const pa_sink_info *, int, void *);
+STATIC void  _pulse_sink_info_cb (pa_context *, const pa_sink_info *, int, void *);
+STATIC void* _pulse_play_thread_fn (void *);
+PUBLIC void  _pulse_refresh_sink (dev_ctx_pulse_T *);
+
+static struct alsa_info **alsa_info = NULL;
+static struct dev_ctx_pulse **dev_ctx_p = NULL;
+static unsigned int client_count = 0;
+
+#endif /* AUDIO_PULSE_H */
diff --git a/plugins/radio/radio-api.c b/plugins/radio/radio-api.c
index d6855fea..919a875f 100644
--- a/plugins/radio/radio-api.c
+++ b/plugins/radio/radio-api.c
@@ -17,7 +17,6 @@
  */
 
 #include "radio-api.h"
-#include "radio-rtlsdr.h"
 
 /* ********************************************************
 
diff --git a/plugins/radio/radio-rtlsdr.c b/plugins/radio/radio-rtlsdr.c
index a8c15faa..b99cf9b7 100644
--- a/plugins/radio/radio-rtlsdr.c
+++ b/plugins/radio/radio-rtlsdr.c
@@ -17,7 +17,6 @@
  */
 
 #include "radio-api.h"
-#include "radio-rtlsdr.h"
 
 /* ------------- RADIO RTLSDR IMPLEMENTATION ---------------- */
 
diff --git a/plugins/radio/radio-rtlsdr.h b/plugins/radio/radio-rtlsdr.h
index 74049a9b..b0c22de0 100644
--- a/plugins/radio/radio-rtlsdr.h
+++ b/plugins/radio/radio-rtlsdr.h
@@ -69,7 +69,7 @@ struct output_ctx {
 };
 
 struct dev_ctx {
-    int used;  // radio is free ???
+    int used;  /* TODO: radio is free ??? */
     rtlsdr_dev_t* dev;
     Mode mode;
     float freq;