1 files changed, 438 insertions, 0 deletions

diff --git a/media/libcubeb/src/cubeb_audiotrack.c b/media/libcubeb/src/cubeb_audiotrack.c
new file mode 100644
index 0000000000..fe2603405e
--- /dev/null
+++ b/media/libcubeb/src/cubeb_audiotrack.c
@@ -0,0 +1,438 @@
+/*
+ * Copyright © 2013 Mozilla Foundation
+ *
+ * This program is made available under an ISC-style license.  See the
+ * accompanying file LICENSE for details.
+ */
+
+#if !defined(NDEBUG)
+#define NDEBUG
+#endif
+#include <assert.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <time.h>
+#include <dlfcn.h>
+#include "android/log.h"
+
+#include "cubeb/cubeb.h"
+#include "cubeb-internal.h"
+#include "android/audiotrack_definitions.h"
+
+#ifndef ALOG
+#if defined(DEBUG) || defined(FORCE_ALOG)
+#define ALOG(args...)  __android_log_print(ANDROID_LOG_INFO, "Gecko - Cubeb" , ## args)
+#else
+#define ALOG(args...)
+#endif
+#endif
+
+/**
+ * A lot of bytes for safety. It should be possible to bring this down a bit. */
+#define SIZE_AUDIOTRACK_INSTANCE 256
+
+/**
+ * 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) {                                                     \
+      ALOG("error while loading %stm: %stm\n", mangled_name, dlerror()); \
+    } else {                                                            \
+      ALOG("%stm: OK", mangled_name);                                   \
+    }                                                                   \
+  } while(0);
+
+static struct cubeb_ops const audiotrack_ops;
+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. */
+  /* 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. */
+  /* static */ status_t (*get_min_frame_count_gingerbread)(int* frame_count, int stream_type, uint32_t rate);
+  void* (*ctor)(void* instance, int, unsigned int, int, int, int, unsigned int, void (*)(int, void*, void*), void*, int, 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);
+  /* 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);
+};
+
+struct cubeb {
+  struct cubeb_ops const * ops;
+  void * library;
+  struct AudioTrack klass;
+};
+
+struct cubeb_stream {
+  cubeb * context;
+  cubeb_stream_params params;
+  cubeb_data_callback data_callback;
+  cubeb_state_callback state_callback;
+  void * instance;
+  void * user_ptr;
+  /* Number of frames that have been passed to the AudioTrack callback */
+  long unsigned written;
+  int draining;
+};
+
+static void
+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;
+
+    if (stream->draining) {
+      return;
+    }
+
+    got = stream->data_callback(stream, stream->user_ptr, NULL, b->raw, b->frameCount);
+
+    stream->written += got;
+
+    if (got != (long)b->frameCount) {
+      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);
+    }
+
+    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;
+  }
+}
+
+/* We are running on gingerbread if we found the gingerbread signature for
+ * getMinFrameCount */
+static int
+audiotrack_version_is_gingerbread(cubeb * ctx)
+{
+  return ctx->klass.get_min_frame_count_gingerbread != NULL;
+}
+
+int
+audiotrack_get_min_frame_count(cubeb * ctx, cubeb_stream_params * params, int * min_frame_count)
+{
+  status_t status;
+  /* Recent Android have a getMinFrameCount method. */
+  if (!audiotrack_version_is_gingerbread(ctx)) {
+    status = ctx->klass.get_min_frame_count(min_frame_count, params->stream_type, params->rate);
+  } else {
+    status = ctx->klass.get_min_frame_count_gingerbread(min_frame_count, params->stream_type, params->rate);
+  }
+  if (status != 0) {
+    ALOG("error getting the min frame count");
+    return CUBEB_ERROR;
+  }
+  return CUBEB_OK;
+}
+
+int
+audiotrack_init(cubeb ** context, char const * context_name)
+{
+  cubeb * ctx;
+  struct AudioTrack* c;
+
+  assert(context);
+  *context = NULL;
+
+  ctx = calloc(1, sizeof(*ctx));
+  assert(ctx);
+
+  /* If we use an absolute path here ("/system/lib/libmedia.so"), and on Android
+   * 2.2, the dlopen succeeds, all the dlsym succeed, but a segfault happens on
+   * the first call to a dlsym'ed function. Somehow this does not happen when
+   * using only the name of the library. */
+  ctx->library = dlopen("libmedia.so", RTLD_LAZY);
+  if (!ctx->library) {
+    ALOG("dlopen error: %s.", dlerror());
+    free(ctx);
+    return CUBEB_ERROR;
+  }
+
+  /* Recent Android first, then Gingerbread. */
+  DLSYM_DLERROR("_ZN7android10AudioTrackC1EijiiijPFviPvS1_ES1_ii", ctx->klass.ctor, ctx->library);
+  DLSYM_DLERROR("_ZN7android10AudioTrackD1Ev", ctx->klass.dtor, ctx->library);
+
+  DLSYM_DLERROR("_ZNK7android10AudioTrack7latencyEv", ctx->klass.latency, ctx->library);
+  DLSYM_DLERROR("_ZNK7android10AudioTrack9initCheckEv", ctx->klass.check, ctx->library);
+
+  DLSYM_DLERROR("_ZN7android11AudioSystem21getOutputSamplingRateEPii", ctx->klass.get_output_samplingrate, ctx->library);
+
+  /* |getMinFrameCount| is available on gingerbread and ICS with different signatures. */
+  DLSYM_DLERROR("_ZN7android10AudioTrack16getMinFrameCountEPi19audio_stream_type_tj", ctx->klass.get_min_frame_count, ctx->library);
+  if (!ctx->klass.get_min_frame_count) {
+    DLSYM_DLERROR("_ZN7android10AudioTrack16getMinFrameCountEPiij", ctx->klass.get_min_frame_count_gingerbread, ctx->library);
+  }
+
+  DLSYM_DLERROR("_ZN7android10AudioTrack5startEv", ctx->klass.start, ctx->library);
+  DLSYM_DLERROR("_ZN7android10AudioTrack5pauseEv", ctx->klass.pause, ctx->library);
+  DLSYM_DLERROR("_ZN7android10AudioTrack11getPositionEPj", ctx->klass.get_position, ctx->library);
+  DLSYM_DLERROR("_ZN7android10AudioTrack17setMarkerPositionEj", ctx->klass.set_marker_position, ctx->library);
+  DLSYM_DLERROR("_ZN7android10AudioTrack9setVolumeEff", ctx->klass.set_volume, ctx->library);
+
+  /* check that we have a combination of symbol that makes sense */
+  c = &ctx->klass;
+  if(!(c->ctor &&
+       c->dtor && c->latency && c->check &&
+       /* at least one way to get the minimum frame count to request. */
+       (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;
+  }
+
+  ctx->ops = &audiotrack_ops;
+
+  *context = ctx;
+
+  return CUBEB_OK;
+}
+
+char const *
+audiotrack_get_backend_id(cubeb * context)
+{
+  return "audiotrack";
+}
+
+static int
+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 */
+  *max_channels = 2;
+
+  return CUBEB_OK;
+}
+
+static int
+audiotrack_get_min_latency(cubeb * ctx, cubeb_stream_params params, uint32_t * latency_ms)
+{
+  /* 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 r;
+
+  r = audiotrack_get_min_frame_count(ctx, &params, (int *)latency_ms);
+  if (r != CUBEB_OK) {
+    return CUBEB_ERROR;
+  }
+
+  return CUBEB_OK;
+}
+
+static int
+audiotrack_get_preferred_sample_rate(cubeb * ctx, uint32_t * rate)
+{
+  status_t r;
+
+  r = ctx->klass.get_output_samplingrate((int32_t *)rate, 3 /* MUSIC */);
+
+  return r == 0 ? CUBEB_OK : CUBEB_ERROR;
+}
+
+void
+audiotrack_destroy(cubeb * context)
+{
+  assert(context);
+
+  dlclose(context->library);
+
+  free(context);
+}
+
+int
+audiotrack_stream_init(cubeb * ctx, cubeb_stream ** stream, char const * stream_name,
+                       cubeb_devid input_device,
+                       cubeb_stream_params * input_stream_params,
+                       cubeb_devid output_device,
+                       cubeb_stream_params * output_stream_params,
+                       unsigned int latency,
+                       cubeb_data_callback data_callback,
+                       cubeb_state_callback state_callback,
+                       void * user_ptr)
+{
+  cubeb_stream * stm;
+  int32_t channels;
+  uint32_t min_frame_count;
+
+  assert(ctx && stream);
+
+  assert(!input_stream_params && "not supported");
+  if (input_device || output_device) {
+    /* Device selection not yet implemented. */
+    return CUBEB_ERROR_DEVICE_UNAVAILABLE;
+  }
+
+  if (output_stream_params->format == CUBEB_SAMPLE_FLOAT32LE ||
+      output_stream_params->format == CUBEB_SAMPLE_FLOAT32BE) {
+    return CUBEB_ERROR_INVALID_FORMAT;
+  }
+
+  if (audiotrack_get_min_frame_count(ctx, output_stream_params, (int *)&min_frame_count)) {
+    return CUBEB_ERROR;
+  }
+
+  stm = calloc(1, sizeof(*stm));
+  assert(stm);
+
+  stm->context = ctx;
+  stm->data_callback = data_callback;
+  stm->state_callback = state_callback;
+  stm->user_ptr = user_ptr;
+  stm->params = *output_stream_params;
+
+  stm->instance = calloc(SIZE_AUDIOTRACK_INSTANCE, 1);
+  (*(uint32_t*)((intptr_t)stm->instance + SIZE_AUDIOTRACK_INSTANCE - 4)) = 0xbaadbaad;
+  assert(stm->instance && "cubeb: EOM");
+
+  /* gingerbread uses old channel layout enum */
+  if (audiotrack_version_is_gingerbread(ctx)) {
+    channels = stm->params.channels == 2 ? AUDIO_CHANNEL_OUT_STEREO_Legacy : AUDIO_CHANNEL_OUT_MONO_Legacy;
+  } else {
+    channels = stm->params.channels == 2 ? AUDIO_CHANNEL_OUT_STEREO_ICS : AUDIO_CHANNEL_OUT_MONO_ICS;
+  }
+
+  ctx->klass.ctor(stm->instance, stm->params.stream_type, stm->params.rate,
+                  AUDIO_FORMAT_PCM_16_BIT, channels, min_frame_count, 0,
+                  audiotrack_refill, stm, 0, 0);
+
+  assert((*(uint32_t*)((intptr_t)stm->instance + SIZE_AUDIOTRACK_INSTANCE - 4)) == 0xbaadbaad);
+
+  if (ctx->klass.check(stm->instance)) {
+    ALOG("stream not initialized properly.");
+    audiotrack_stream_destroy(stm);
+    return CUBEB_ERROR;
+  }
+
+  *stream = stm;
+
+  return CUBEB_OK;
+}
+
+void
+audiotrack_stream_destroy(cubeb_stream * stream)
+{
+  assert(stream->context);
+
+  stream->context->klass.dtor(stream->instance);
+
+  free(stream->instance);
+  stream->instance = NULL;
+  free(stream);
+}
+
+int
+audiotrack_stream_start(cubeb_stream * stream)
+{
+  assert(stream->instance);
+
+  stream->context->klass.start(stream->instance);
+  stream->state_callback(stream, stream->user_ptr, CUBEB_STATE_STARTED);
+
+  return CUBEB_OK;
+}
+
+int
+audiotrack_stream_stop(cubeb_stream * stream)
+{
+  assert(stream->instance);
+
+  stream->context->klass.pause(stream->instance);
+  stream->state_callback(stream, stream->user_ptr, CUBEB_STATE_STOPPED);
+
+  return CUBEB_OK;
+}
+
+int
+audiotrack_stream_get_position(cubeb_stream * stream, uint64_t * position)
+{
+  uint32_t p;
+
+  assert(stream->instance && position);
+  stream->context->klass.get_position(stream->instance, &p);
+  *position = p;
+
+  return CUBEB_OK;
+}
+
+int
+audiotrack_stream_get_latency(cubeb_stream * stream, uint32_t * latency)
+{
+  assert(stream->instance && latency);
+
+  /* Android returns the latency in ms, we want it in frames. */
+  *latency = stream->context->klass.latency(stream->instance);
+  /* with rate <= 96000, we won't overflow until 44.739 seconds of latency */
+  *latency = (*latency * stream->params.rate) / 1000;
+
+  return 0;
+}
+
+int
+audiotrack_stream_set_volume(cubeb_stream * stream, float volume)
+{
+  status_t status;
+
+  status = stream->context->klass.set_volume(stream->instance, volume, volume);
+
+  if (status) {
+    return CUBEB_ERROR;
+  }
+
+  return CUBEB_OK;
+}
+
+static struct cubeb_ops const audiotrack_ops = {
+  .init = audiotrack_init,
+  .get_backend_id = audiotrack_get_backend_id,
+  .get_max_channel_count = audiotrack_get_max_channel_count,
+  .get_min_latency = audiotrack_get_min_latency,
+  .get_preferred_sample_rate = audiotrack_get_preferred_sample_rate,
+  .enumerate_devices = NULL,
+  .destroy = audiotrack_destroy,
+  .stream_init = audiotrack_stream_init,
+  .stream_destroy = audiotrack_stream_destroy,
+  .stream_start = audiotrack_stream_start,
+  .stream_stop = audiotrack_stream_stop,
+  .stream_get_position = audiotrack_stream_get_position,
+  .stream_get_latency = audiotrack_stream_get_latency,
+  .stream_set_volume = audiotrack_stream_set_volume,
+  .stream_set_panning = NULL,
+  .stream_get_current_device = NULL,
+  .stream_device_destroy = NULL,
+  .stream_register_device_changed_callback = NULL,
+  .register_device_collection_changed = NULL
+};