/*
Brute-force device detection, using a base device name (eg: \\.\WaveOut).
This will add the device number as a suffix to the end of the string and
attempt to open the device based on that name. On success, it will
increment the device number and repeat this process.
When it runs out of devices, it will give up.
*/
MMRESULT
DetectNt4SoundDevices(
IN MMDEVICE_TYPE DeviceType,
IN PWSTR BaseDeviceName,
IN SOUND_DEVICE_DETECTED_PROC SoundDeviceDetectedProc)
{
ULONG DeviceNameLength = 0;
PWSTR DeviceName = NULL;
ULONG Index = 0;
HANDLE DeviceHandle;
BOOLEAN DoSearch = TRUE;
VALIDATE_MMSYS_PARAMETER( IsValidSoundDeviceType(DeviceType) );
DeviceNameLength = wcslen(BaseDeviceName);
/* Consider the length of the number */
DeviceNameLength += GetDigitCount(Index);
DeviceName = AllocateWideString(DeviceNameLength);
if ( ! DeviceName )
{
return MMSYSERR_NOMEM;
}
while ( DoSearch )
{
/* Nothing like a nice clean device name */
ZeroWideString(DeviceName);
wsprintf(DeviceName, L"%ls%d", BaseDeviceName, Index);
if ( OpenKernelSoundDeviceByName(DeviceName,
TRUE,
&DeviceHandle) == MMSYSERR_NOERROR )
{
/* Notify the callback function */
SND_TRACE(L"Found device: %wS\n", DeviceName);
SoundDeviceDetectedProc(DeviceType, DeviceName);
CloseHandle(DeviceHandle);
++ Index;
}
else
{
DoSearch = FALSE;
}
}
FreeMemory(DeviceName);
return MMSYSERR_NOERROR;
}
/*
Convenience routine for getting the path of a device and opening it.
*/
MMRESULT
OpenNt4KernelSoundDevice(
IN PSOUND_DEVICE SoundDevice,
IN BOOLEAN ReadOnly,
OUT PHANDLE Handle)
{
PWSTR Path;
MMRESULT Result;
VALIDATE_MMSYS_PARAMETER( IsValidSoundDevice(SoundDevice) );
VALIDATE_MMSYS_PARAMETER( Handle );
Result = GetSoundDeviceIdentifier(SoundDevice, (PVOID*) &Path);
if ( ! MMSUCCESS(Result) )
{
SND_ERR(L"Unable to get sound device path");
return TranslateInternalMmResult(Result);
}
SND_ASSERT( Path );
return OpenKernelSoundDeviceByName(Path, ReadOnly, Handle);
}
