// static
OSStatus BGMDeviceControlSync::AHSSetPropertyData(AudioObjectID inObjectID, const AudioObjectPropertyAddress* inAddress, UInt32 inDataSize, const void* inData)
{
// See the explanation about these pragmas in AHSGetPropertyData
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wnonnull"
return AudioHardwareServiceSetPropertyData(inObjectID, inAddress, 0, NULL, inDataSize, inData);
#pragma clang diagnostic pop
}
bool setMuted (bool mute)
{
if (outputDeviceID != kAudioObjectUnknown && canSetVolume())
{
UInt32 newMute = mute ? 1 : 0;
UInt32 size = sizeof (newMute);
return AudioHardwareServiceSetPropertyData (outputDeviceID, &addr, 0, nullptr,
size, &newMute) == noErr;
}
return false;
}
bool setGain (float gain)
{
if (outputDeviceID != kAudioObjectUnknown && canSetVolume())
{
Float32 newVolume = gain;
UInt32 size = sizeof (newVolume);
return AudioHardwareServiceSetPropertyData (outputDeviceID, &addr, 0, nullptr,
size, &newVolume) == noErr;
}
return false;
}
// setting system volume. Mutes if under threshhold.
// Courtesy: https://gist.github.com/atr000/205140
int setVolume(float newVolume) {
if (newVolume < 0.0 || newVolume > 1.0) {
fprintf(stderr, "ERROR: Requested volume out of range (%.2f)\n", newVolume);
return 1;
}
// get output device
UInt32 propertySize = 0;
OSStatus status = noErr;
AudioObjectPropertyAddress propertyAOPA;
propertyAOPA.mElement = kAudioObjectPropertyElementMaster;
propertyAOPA.mScope = kAudioDevicePropertyScopeOutput;
if (newVolume < 0.001) {
propertyAOPA.mSelector = kAudioDevicePropertyMute;
} else {
propertyAOPA.mSelector = kAudioHardwareServiceDeviceProperty_VirtualMasterVolume;
}
AudioDeviceID outputDeviceID = defaultOutputDeviceID();
if (outputDeviceID == kAudioObjectUnknown) {
fprintf(stderr, "ERROR: Unknown device\n");
return 2;
}
if (!AudioHardwareServiceHasProperty(outputDeviceID, &propertyAOPA)) {
fprintf(stderr, "ERROR: Device 0x%0x does not support volume control\n", outputDeviceID);
return 3;
}
Boolean canSetVolume = false;
status = AudioHardwareServiceIsPropertySettable(outputDeviceID, &propertyAOPA, &canSetVolume);
if (status || !canSetVolume) {
fprintf(stderr, "ERROR: Device 0x%0x does not support volume control\n", outputDeviceID);
return 4;
}
if (propertyAOPA.mSelector == kAudioDevicePropertyMute) {
propertySize = sizeof(UInt32);
UInt32 mute = 1;
status = AudioHardwareServiceSetPropertyData(outputDeviceID, &propertyAOPA, 0, NULL, propertySize, &mute);
} else {
propertySize = sizeof(Float32);
status = AudioHardwareServiceSetPropertyData(outputDeviceID, &propertyAOPA, 0, NULL, propertySize, &newVolume);
if (status) {
fprintf(stderr, "ERROR: Unable to set volume for device 0x%0x\n", outputDeviceID);
return 5;
}
// make sure we're not muted
propertyAOPA.mSelector = kAudioDevicePropertyMute;
propertySize = sizeof(UInt32);
UInt32 mute = 0;
if (!AudioHardwareServiceHasProperty(outputDeviceID, &propertyAOPA)) {
fprintf(stderr, "ERROR: Device 0x%0x does not support muting\n", outputDeviceID);
return 6;
}
Boolean canSetMute = false;
status = AudioHardwareServiceIsPropertySettable(outputDeviceID, &propertyAOPA, &canSetMute);
if (status || !canSetMute) {
fprintf(stderr, "ERROR: Device 0x%0x does not support muting\n", outputDeviceID);
return 7;
}
status = AudioHardwareServiceSetPropertyData(outputDeviceID, &propertyAOPA, 0, NULL, propertySize, &mute);
}
if (status) {
fprintf(stderr, "ERROR: Unable to set volume for device 0x%0x\n", outputDeviceID);
return 8;
}
return 0;
}
