clarify and clean up handling of optional functions in the API. fixes #46.

1 files changed, 71 insertions, 78 deletions

diff --git a/src/cubeb_audiotrack.c b/src/cubeb_audiotrack.c
index e2c65d7..e296e1d 100644
--- a/src/cubeb_audiotrack.c
+++ b/src/cubeb_audiotrack.c
@@ -35,14 +35,14 @@
  * call dlsym to get the symbol |mangled_name|, handle the error and store the
  * pointer in |pointer|. Because depending on Android version, we want different
  * symbols, not finding a symbol is not an error. */
-#define DLSYM_DLERROR(mangled_name, pointer, lib)                        \
-  do {                                                                   \
-    pointer = dlsym(lib, mangled_name);                                  \
-    if (!pointer) {                                                      \
+#define DLSYM_DLERROR(mangled_name, pointer, lib)                       \
+  do {                                                                  \
+    pointer = dlsym(lib, mangled_name);                                 \
+    if (!pointer) {                                                     \
       ALOG("error while loading %stm: %stm\n", mangled_name, dlerror()); \
-    } else {                                                             \
-      ALOG("%stm: OK", mangled_name);                                    \
-    }                                                                    \
+    } else {                                                            \
+      ALOG("%stm: OK", mangled_name);                                   \
+    }                                                                   \
   } while(0);
 
 static struct cubeb_ops const audiotrack_ops;
@@ -50,28 +50,28 @@ void audiotrack_destroy(cubeb * context);
 void audiotrack_stream_destroy(cubeb_stream * stream);
 
 struct AudioTrack {
-               /* only available on ICS and later. The second int paramter is in fact of type audio_stream_type_t. */
+  /* only available on ICS and later. The second int paramter is in fact of type audio_stream_type_t. */
   /* static */ status_t (*get_min_frame_count)(int* frame_count, int stream_type, uint32_t rate);
-              /* if we have a recent ctor, but can't find the above symbol, we
-               * can get the minimum frame count with this signature, and we are
-               * running gingerbread. */
+  /* if we have a recent ctor, but can't find the above symbol, we
+   * can get the minimum frame count with this signature, and we are
+   * running gingerbread. */
   /* static */ status_t (*get_min_frame_count_gingerbread)(int* frame_count, int stream_type, uint32_t rate);
-               /* if this symbol is not availble, and the next one is, we know
-                * we are on a Froyo (Android 2.2) device. */
-               void* (*ctor)(void* instance, int, unsigned int, int, int, int, unsigned int, void (*)(int, void*, void*), void*, int, int);
-               void* (*ctor_froyo)(void* instance, int, unsigned int, int, int, int, unsigned int, void (*)(int, void*, void*), void*, int);
-               void* (*dtor)(void* instance);
-               void (*start)(void* instance);
-               void (*pause)(void* instance);
-               uint32_t (*latency)(void* instance);
-               status_t (*check)(void* instance);
-               status_t (*get_position)(void* instance, uint32_t* position);
-              /* only used on froyo. */
+  /* if this symbol is not availble, and the next one is, we know
+   * we are on a Froyo (Android 2.2) device. */
+  void* (*ctor)(void* instance, int, unsigned int, int, int, int, unsigned int, void (*)(int, void*, void*), void*, int, int);
+  void* (*ctor_froyo)(void* instance, int, unsigned int, int, int, int, unsigned int, void (*)(int, void*, void*), void*, int);
+  void* (*dtor)(void* instance);
+  void (*start)(void* instance);
+  void (*pause)(void* instance);
+  uint32_t (*latency)(void* instance);
+  status_t (*check)(void* instance);
+  status_t (*get_position)(void* instance, uint32_t* position);
+  /* only used on froyo. */
   /* static */ int (*get_output_frame_count)(int* frame_count, int stream);
   /* static */ int (*get_output_latency)(uint32_t* latency, int stream);
   /* static */ int (*get_output_samplingrate)(int* samplerate, int stream);
-               status_t (*set_marker_position)(void* instance, unsigned int);
-               status_t (*set_volume)(void* instance, float left, float right);
+  status_t (*set_marker_position)(void* instance, unsigned int);
+  status_t (*set_volume)(void* instance, float left, float right);
 };
 
 struct cubeb {
@@ -97,44 +97,44 @@ audiotrack_refill(int event, void* user, void* info)
 {
   cubeb_stream * stream = user;
   switch (event) {
-    case EVENT_MORE_DATA: {
-      long got = 0;
-      struct Buffer * b = (struct Buffer*)info;
+  case EVENT_MORE_DATA: {
+    long got = 0;
+    struct Buffer * b = (struct Buffer*)info;
 
-      if (stream->draining) {
-        return;
-      }
-
-      got = stream->data_callback(stream, stream->user_ptr, b->raw, b->frameCount);
+    if (stream->draining) {
+      return;
+    }
 
-      stream->written += got;
+    got = stream->data_callback(stream, stream->user_ptr, b->raw, b->frameCount);
 
-      if (got != (long)b->frameCount) {
-        uint32_t p;
-        stream->draining = 1;
-        /* set a marker so we are notified when the are done draining, that is,
-         * when every frame has been played by android. */
-        stream->context->klass.set_marker_position(stream->instance, stream->written);
-      }
+    stream->written += got;
 
-      break;
+    if (got != (long)b->frameCount) {
+      uint32_t p;
+      stream->draining = 1;
+      /* set a marker so we are notified when the are done draining, that is,
+       * when every frame has been played by android. */
+      stream->context->klass.set_marker_position(stream->instance, stream->written);
     }
-    case EVENT_UNDERRUN:
-      ALOG("underrun in cubeb backend.");
-      break;
-    case EVENT_LOOP_END:
-      assert(0 && "We don't support the loop feature of audiotrack.");
-      break;
-    case EVENT_MARKER:
-      assert(stream->draining);
-      stream->state_callback(stream, stream->user_ptr, CUBEB_STATE_DRAINED);
-      break;
-    case EVENT_NEW_POS:
-      assert(0 && "We don't support the setPositionUpdatePeriod feature of audiotrack.");
-      break;
-    case EVENT_BUFFER_END:
-      assert(0 && "Should not happen.");
-      break;
+
+    break;
+  }
+  case EVENT_UNDERRUN:
+    ALOG("underrun in cubeb backend.");
+    break;
+  case EVENT_LOOP_END:
+    assert(0 && "We don't support the loop feature of audiotrack.");
+    break;
+  case EVENT_MARKER:
+    assert(stream->draining);
+    stream->state_callback(stream, stream->user_ptr, CUBEB_STATE_DRAINED);
+    break;
+  case EVENT_NEW_POS:
+    assert(0 && "We don't support the setPositionUpdatePeriod feature of audiotrack.");
+    break;
+  case EVENT_BUFFER_END:
+    assert(0 && "Should not happen.");
+    break;
   }
 }
 
@@ -256,12 +256,12 @@ audiotrack_init(cubeb ** context, char const * context_name)
   /* check that we have a combination of symbol that makes sense */
   c = &ctx->klass;
   if(!((c->ctor || c->ctor_froyo) && /* at least on ctor. */
-     c->dtor && c->latency && c->check &&
-     /* at least one way to get the minimum frame count to request. */
-     ((c->get_output_frame_count && c->get_output_latency && c->get_output_samplingrate) ||
-      c->get_min_frame_count ||
-      c->get_min_frame_count_gingerbread) &&
-     c->start && c->pause && c->get_position && c->set_marker_position)) {
+       c->dtor && c->latency && c->check &&
+       /* at least one way to get the minimum frame count to request. */
+       ((c->get_output_frame_count && c->get_output_latency && c->get_output_samplingrate) ||
+        c->get_min_frame_count ||
+        c->get_min_frame_count_gingerbread) &&
+       c->start && c->pause && c->get_position && c->set_marker_position)) {
     ALOG("Could not find all the symbols we need.");
     audiotrack_destroy(ctx);
     return CUBEB_ERROR;
@@ -286,7 +286,7 @@ audiotrack_get_max_channel_count(cubeb * ctx, uint32_t * max_channels)
   assert(ctx && max_channels);
 
   /* The android mixer handles up to two channels, see
-  http://androidxref.com/4.2.2_r1/xref/frameworks/av/services/audioflinger/AudioFlinger.h#67 */
+     http://androidxref.com/4.2.2_r1/xref/frameworks/av/services/audioflinger/AudioFlinger.h#67 */
   *max_channels = 2;
 
   return CUBEB_OK;
@@ -297,10 +297,10 @@ audiotrack_get_min_latency(cubeb * ctx, cubeb_stream_params params, uint32_t * l
 {
   /* We always use the lowest latency possible when using this backend (see
    * audiotrack_stream_init), so this value is not going to be used. */
-  int rv;
+  int r;
 
-  rv = audiotrack_get_min_frame_count(ctx, &params, (int *)latency_ms);
-  if (rv != CUBEB_OK) {
+  r = audiotrack_get_min_frame_count(ctx, &params, (int *)latency_ms);
+  if (r != CUBEB_OK) {
     return CUBEB_ERROR;
   }
 
@@ -313,11 +313,11 @@ audiotrack_get_min_latency(cubeb * ctx, cubeb_stream_params params, uint32_t * l
 static int
 audiotrack_get_preferred_sample_rate(cubeb * ctx, uint32_t * rate)
 {
-  status_t rv;
+  status_t r;
 
-  rv = ctx->klass.get_output_samplingrate((int32_t *)rate, 3 /* MUSIC */);
+  r = ctx->klass.get_output_samplingrate((int32_t *)rate, 3 /* MUSIC */);
 
-  return rv == 0 ? CUBEB_OK : CUBEB_ERROR;
+  return r == 0 ? CUBEB_OK : CUBEB_ERROR;
 }
 
 void
@@ -483,13 +483,6 @@ audiotrack_stream_set_volume(cubeb_stream * stream, float volume)
   return CUBEB_OK;
 }
 
-int
-audiotrack_stream_set_panning(cubeb_stream * stream, float panning)
-{
-  assert(false && "not implemented.");
-  return CUBEB_OK;
-}
-
 static struct cubeb_ops const audiotrack_ops = {
   .init = audiotrack_init,
   .get_backend_id = audiotrack_get_backend_id,
@@ -504,7 +497,7 @@ static struct cubeb_ops const audiotrack_ops = {
   .stream_get_position = audiotrack_stream_get_position,
   .stream_get_latency = audiotrack_stream_get_latency,
   .stream_set_volume = audiotrack_stream_set_volume,
-  .stream_set_panning = audiotrack_stream_set_panning,
+  .stream_set_panning = NULL,
   .stream_get_current_device = NULL,
   .stream_device_destroy = NULL,
   .stream_register_device_changed_callback = NULL