OSStatus ca_unlock_device(AudioDeviceID device, pid_t *pid) {
if (*pid == getpid()) {
*pid = -1;
return CA_SET(device, kAudioDevicePropertyHogMode, &pid);
}
return noErr;
}
OSStatus ca_lock_device(AudioDeviceID device, pid_t *pid) {
*pid = getpid();
OSStatus err = CA_SET(device, kAudioDevicePropertyHogMode, pid);
if (err != noErr)
*pid = -1;
return err;
}
static OSStatus ca_change_mixing(struct ao *ao, AudioDeviceID device,
uint32_t val, bool *changed) {
*changed = false;
AudioObjectPropertyAddress p_addr = (AudioObjectPropertyAddress) {
.mSelector = kAudioDevicePropertySupportsMixing,
.mScope = kAudioObjectPropertyScopeGlobal,
.mElement = kAudioObjectPropertyElementMaster,
};
if (AudioObjectHasProperty(device, &p_addr)) {
OSStatus err;
Boolean writeable = 0;
err = CA_SETTABLE(device, kAudioDevicePropertySupportsMixing,
&writeable);
if (!CHECK_CA_WARN("can't tell if mixing property is settable")) {
return err;
}
if (!writeable)
return noErr;
err = CA_SET(device, kAudioDevicePropertySupportsMixing, &val);
if (err != noErr)
return err;
if (!CHECK_CA_WARN("can't set mix mode")) {
return err;
}
*changed = true;
}
return noErr;
}
static bool init_audiounit(struct ao *ao, AudioStreamBasicDescription asbd)
{
OSStatus err;
uint32_t size;
struct priv *p = ao->priv;
AudioComponentDescription desc = (AudioComponentDescription) {
.componentType = kAudioUnitType_Output,
.componentSubType = (ao->device) ?
kAudioUnitSubType_HALOutput :
kAudioUnitSubType_DefaultOutput,
.componentManufacturer = kAudioUnitManufacturer_Apple,
.componentFlags = 0,
.componentFlagsMask = 0,
};
AudioComponent comp = AudioComponentFindNext(NULL, &desc);
if (comp == NULL) {
MP_ERR(ao, "unable to find audio component\n");
goto coreaudio_error;
}
err = AudioComponentInstanceNew(comp, &(p->audio_unit));
CHECK_CA_ERROR("unable to open audio component");
err = AudioUnitInitialize(p->audio_unit);
CHECK_CA_ERROR_L(coreaudio_error_component,
"unable to initialize audio unit");
size = sizeof(AudioStreamBasicDescription);
err = AudioUnitSetProperty(p->audio_unit,
kAudioUnitProperty_StreamFormat,
kAudioUnitScope_Input, 0, &asbd, size);
CHECK_CA_ERROR_L(coreaudio_error_audiounit,
"unable to set the input format on the audio unit");
err = AudioUnitSetProperty(p->audio_unit,
kAudioOutputUnitProperty_CurrentDevice,
kAudioUnitScope_Global, 0, &p->device,
sizeof(p->device));
CHECK_CA_ERROR_L(coreaudio_error_audiounit,
"can't link audio unit to selected device");
p->hw_latency_us = ca_get_hardware_latency(ao);
AURenderCallbackStruct render_cb = (AURenderCallbackStruct) {
.inputProc = render_cb_lpcm,
.inputProcRefCon = ao,
};
err = AudioUnitSetProperty(p->audio_unit,
kAudioUnitProperty_SetRenderCallback,
kAudioUnitScope_Input, 0, &render_cb,
sizeof(AURenderCallbackStruct));
CHECK_CA_ERROR_L(coreaudio_error_audiounit,
"unable to set render callback on audio unit");
return true;
coreaudio_error_audiounit:
AudioUnitUninitialize(p->audio_unit);
coreaudio_error_component:
AudioComponentInstanceDispose(p->audio_unit);
coreaudio_error:
return false;
}
static void stop(struct ao *ao)
{
struct priv *p = ao->priv;
OSStatus err = AudioOutputUnitStop(p->audio_unit);
CHECK_CA_WARN("can't stop audio unit");
}
static void start(struct ao *ao)
{
struct priv *p = ao->priv;
OSStatus err = AudioOutputUnitStart(p->audio_unit);
CHECK_CA_WARN("can't start audio unit");
}
static void uninit(struct ao *ao)
{
struct priv *p = ao->priv;
AudioOutputUnitStop(p->audio_unit);
AudioUnitUninitialize(p->audio_unit);
AudioComponentInstanceDispose(p->audio_unit);
if (p->original_asbd.mFormatID) {
OSStatus err = CA_SET(p->original_asbd_stream,
kAudioStreamPropertyPhysicalFormat,
&p->original_asbd);
CHECK_CA_WARN("could not restore physical stream format");
}
}
static OSStatus hotplug_cb(AudioObjectID id, UInt32 naddr,
const AudioObjectPropertyAddress addr[],
void *ctx) {
reinit_device(ctx);
ao_hotplug_event(ctx);
return noErr;
}
