static int
opensl_get_preferred_sample_rate(cubeb * ctx, uint32_t * rate)
{
/* https://android.googlesource.com/platform/ndk.git/+/master/docs/opensles/index.html
* We don't want to deal with JNI here (and we don't have Java on b2g anyways,
* so we just dlopen the library and get the two symbols we need. */
int rv;
void * libmedia;
uint32_t (*get_primary_output_samplingrate)();
uint32_t primary_sampling_rate;
libmedia = dlopen("libmedia.so", RTLD_LAZY);
if (!libmedia) {
return CUBEB_ERROR;
}
/* uint32_t AudioSystem::getPrimaryOutputSamplingRate(void) */
get_primary_output_samplingrate =
dlsym(libmedia, "_ZN7android11AudioSystem28getPrimaryOutputSamplingRateEv");
if (!get_primary_output_samplingrate) {
dlclose(libmedia);
return CUBEB_ERROR;
}
*rate = get_primary_output_samplingrate();
dlclose(libmedia);
return CUBEB_OK;
}
static int
opensl_get_preferred_sample_rate(cubeb * ctx, uint32_t * rate)
{
/* https://android.googlesource.com/platform/ndk.git/+/master/docs/opensles/index.html
* We don't want to deal with JNI here (and we don't have Java on b2g anyways),
* so we just dlopen the library and get the two symbols we need. */
int rv;
void * libmedia;
uint32_t (*get_primary_output_samplingrate)();
uint32_t (*get_output_samplingrate)(int * samplingRate, int streamType);
uint32_t primary_sampling_rate;
libmedia = dlopen("libmedia.so", RTLD_LAZY);
if (!libmedia) {
return CUBEB_ERROR;
}
/* uint32_t AudioSystem::getPrimaryOutputSamplingRate(void) */
get_primary_output_samplingrate =
dlsym(libmedia, "_ZN7android11AudioSystem28getPrimaryOutputSamplingRateEv");
if (!get_primary_output_samplingrate) {
/* fallback to
* status_t AudioSystem::getOutputSamplingRate(int* samplingRate, int streamType)
* if we cannot find getPrimaryOutputSamplingRate. */
get_output_samplingrate =
dlsym(libmedia, "_ZN7android11AudioSystem21getOutputSamplingRateEPj19audio_stream_type_t");
if (!get_output_samplingrate) {
/* Another signature exists, with a int instead of an audio_stream_type_t */
get_output_samplingrate =
dlsym(libmedia, "_ZN7android11AudioSystem21getOutputSamplingRateEPii");
if (!get_output_samplingrate) {
dlclose(libmedia);
return CUBEB_ERROR;
}
}
}
if (get_primary_output_samplingrate) {
*rate = get_primary_output_samplingrate();
} else {
/* We don't really know about the type, here, so we just pass music. */
rv = get_output_samplingrate((int *) rate, AUDIO_STREAM_TYPE_MUSIC);
if (rv) {
dlclose(libmedia);
return CUBEB_ERROR;
}
}
dlclose(libmedia);
/* Depending on which method we called above, we can get a zero back, yet have
* a non-error return value, especially if the audio system is not
* ready/shutting down (i.e. when we can't get our hand on the AudioFlinger
* thread). */
if (*rate == 0) {
return CUBEB_ERROR;
}
return CUBEB_OK;
}
static int
opensl_get_min_latency(cubeb * ctx, cubeb_stream_params params, uint32_t * latency_ms)
{
/* https://android.googlesource.com/platform/ndk.git/+/master/docs/opensles/index.html
* We don't want to deal with JNI here (and we don't have Java on b2g anyways),
* so we just dlopen the library and get the two symbols we need. */
int rv;
void * libmedia;
uint32_t (*get_primary_output_samplingrate)(void);
size_t (*get_primary_output_frame_count)(void);
uint32_t primary_sampling_rate;
size_t primary_buffer_size;
libmedia = dlopen("libmedia.so", RTLD_LAZY);
if (!libmedia) {
return CUBEB_ERROR;
}
/* uint32_t AudioSystem::getPrimaryOutputSamplingRate(void) */
get_primary_output_samplingrate =
dlsym(libmedia, "_ZN7android11AudioSystem28getPrimaryOutputSamplingRateEv");
if (!get_primary_output_samplingrate) {
dlclose(libmedia);
return CUBEB_ERROR;
}
/* size_t AudioSystem::getPrimaryOutputFrameCount(void) */
get_primary_output_frame_count =
dlsym(libmedia, "_ZN7android11AudioSystem26getPrimaryOutputFrameCountEv");
if (!get_primary_output_frame_count) {
dlclose(libmedia);
return CUBEB_ERROR;
}
primary_sampling_rate = get_primary_output_samplingrate();
primary_buffer_size = get_primary_output_frame_count();
/* To get a fast track in Android's mixer, we need to be at the native
* samplerate, which is device dependant. Some devices might be able to
* resample when playing a fast track, but it's pretty rare. */
if (primary_sampling_rate != params.rate) {
/* If we don't know what to use, let's say 4 * 20ms buffers will do. */
*latency_ms = NBUFS * 20;
} else {
*latency_ms = NBUFS * primary_buffer_size / (primary_sampling_rate / 1000);
}
dlclose(libmedia);
return CUBEB_OK;
}
