NTSTATUS
SoundWaveDispatch(
IN OUT PLOCAL_DEVICE_INFO pLDI,
IN PIRP pIrp,
IN PIO_STACK_LOCATION IrpStack
);
The SoundWaveDispatch function is the IRP control code dispatcher for waveform devices.
Parameters
pLDI
Pointer to a LOCAL_DEVICE_INFO structure.
pIrp
Pointer to an IRP structure.
IrpStack
Pointer to an IO_STACK_LOCATION structure.
Return Value
Returns STATUS_SUCCESS if the operation succeeds. Otherwise returns an NTSTATUS error code.
Comments
Kernel-mode waveform device drivers using soundlib.lib place the address of the SoundWaveDispatch function in the DispatchRoutine member of a SOUND_DEVICE_INIT structure. The function is called by soundlib.lib's main dispatcher, SoundDispatch.
The function processes the following IRP control codes:
| IRP_MJ_CLEANUP |
| IRP_MJ_CLOSE |
| IRP_MJ_CREATE |
| IRP_MJ_DEVICE_CONTROL |
| IRP_MJ_READ |
| IRP_MJ_WRITE |
For IRP_MJ_DEVICE_CONTROL, the function processes the following I/O control codes:
| IOCTL_SOUND_GET_CHANGED_VOLUME |
| IOCTL_WAVE_GET_CAPABILITIES |
| IOCTL_WAVE_GET_PITCH |
| IOCTL_WAVE_GET_PLAYBACK_RATE |
| IOCTL_WAVE_GET_POSITION |
| IOCTL_WAVE_GET_POSITION |
| IOCTL_WAVE_GET_STATE |
| IOCTL_WAVE_GET_VOLUME |
| IOCTL_WAVE_QUERY_FORMAT |
| IOCTL_WAVE_SET_FORMAT |
| IOCTL_WAVE_SET_LOW_PRIORITY |
| IOCTL_WAVE_SET_PITCH |
| IOCTL_WAVE_SET_PLAYBACK_RATE |
| IOCTL_WAVE_SET_STATE |