devname.h File Reference

Go to the source code of this file.

Functions
NTSTATUS	ConstructDeviceName (IN PCWSTR Path, IN UCHAR Index, OUT PUNICODE_STRING DeviceName)
VOID	FreeUnicodeStringBuffer (IN PUNICODE_STRING String)
NTSTATUS	GetDefaultSoundDeviceNameBodies (IN UCHAR DeviceType, OUT PCWSTR *DeviceNameBody, OUT PCWSTR *DosDeviceNameBody)
NTSTATUS	ConstructSoundDeviceNames (IN PCWSTR DeviceNameBody, IN PCWSTR DosDeviceNameBody, IN UCHAR Index, OUT PUNICODE_STRING FullDeviceName, OUT PUNICODE_STRING FullDosDeviceName)
NTSTATUS	CreateSoundDevice (IN PDRIVER_OBJECT DriverObject, IN PCWSTR WideDeviceName, IN PCWSTR WideDosDeviceName, IN UCHAR Index, IN ULONG ExtensionSize, OUT PDEVICE_OBJECT *DeviceObject)
NTSTATUS	CreateSoundDeviceWithDefaultName (IN PDRIVER_OBJECT DriverObject, IN UCHAR DeviceType, IN UCHAR Index, IN ULONG ExtensionSize, OUT PDEVICE_OBJECT *DeviceObject)
NTSTATUS	DestroySoundDevice (IN PDEVICE_OBJECT DeviceObject, IN PCWSTR WideDosDeviceName, IN UCHAR Index)
NTSTATUS	DestroySoundDeviceWithDefaultName (IN PDEVICE_OBJECT DeviceObject, IN UCHAR DeviceType, IN UCHAR Index)

Function Documentation

ConstructDeviceName()

NTSTATUS ConstructDeviceName	(	IN PCWSTR	Path,
		IN UCHAR	Index,
		OUT PUNICODE_STRING	DeviceName
	)

Definition at line 73 of file devname.c.

{
    UNICODE_STRING UnicodePath;
    UNICODE_STRING UnicodeIndex;
    WCHAR IndexStringBuffer[5];
    USHORT Size;
    USHORT LastCharacterIndex;
 
    /* Check for NULL parameters */
    if ( ( ! Path ) || ( ! DeviceName ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device index %d out of range", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Initialise the unicode path string */
    RtlInitUnicodeString(&UnicodePath, Path);
 
    /* Calculate the length to hold the full string */
    Size = UnicodePath.Length +
           sizeof(IndexStringBuffer) +
           sizeof(UNICODE_NULL);
 
    /* Allocate memory for DeviceName */
    DeviceName->Buffer = ExAllocatePool(PagedPool, Size);
    DeviceName->MaximumLength = Size;
 
    if ( ! DeviceName->Buffer )
    {
        DPRINT("Couldn't allocate memory for device name string");
        return STATUS_INSUFFICIENT_RESOURCES;
    }
 
    /* Copy the path */
    RtlCopyUnicodeString(DeviceName, &UnicodePath);
 
    /* Convert Index to string and append */
    UnicodeIndex.Buffer = IndexStringBuffer;
    UnicodeIndex.MaximumLength = sizeof(IndexStringBuffer);
 
    RtlIntegerToUnicodeString((ULONG)Index, 10, &UnicodeIndex);
    RtlAppendUnicodeStringToString(DeviceName, &UnicodeIndex);
 
    /* Terminate the string */
    LastCharacterIndex = DeviceName->Length / sizeof(UNICODE_NULL);
    DeviceName->Buffer[LastCharacterIndex] = UNICODE_NULL;
 
    return STATUS_SUCCESS;
}

Referenced by ConstructSoundDeviceNames(), and DestroySoundDevice().

ConstructSoundDeviceNames()

NTSTATUS ConstructSoundDeviceNames	(	IN PCWSTR	DeviceNameBody,
		IN PCWSTR	DosDeviceNameBody,
		IN UCHAR	Index,
		OUT PUNICODE_STRING	FullDeviceName,
		OUT PUNICODE_STRING	FullDosDeviceName
	)

Definition at line 207 of file devname.c.

{
    NTSTATUS Status;
 
    /* Check for NULL parameters */
    if ( ( ! DeviceNameBody ) || ( ! DosDeviceNameBody ) ||
         ( ! FullDeviceName ) || ( ! FullDosDeviceName ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device %d exceeds maximum", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    Status = ConstructDeviceName(DeviceNameBody, Index, FullDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        /* No need to clean up on failure here */
        return Status;
    }
 
    Status = ConstructDeviceName(DosDeviceNameBody, Index, FullDosDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        /* We need to free the string we successfully got earlier */
        FreeUnicodeStringBuffer(FullDeviceName);
        return Status;
    }
 
    return STATUS_SUCCESS;
}

Referenced by CreateSoundDevice().

CreateSoundDevice()

NTSTATUS CreateSoundDevice	(	IN PDRIVER_OBJECT	DriverObject,
		IN PCWSTR	WideDeviceName,
		IN PCWSTR	WideDosDeviceName,
		IN UCHAR	Index,
		IN ULONG	ExtensionSize,
		OUT PDEVICE_OBJECT *	DeviceObject
	)

Definition at line 261 of file devname.c.

{
    NTSTATUS Status;
 
    UNICODE_STRING DeviceName;
    UNICODE_STRING DosDeviceName;
 
    /* Check for NULL parameters */
    if ( ( ! DriverObject ) || ( ! DeviceObject ) ||
         ( ! WideDeviceName ) || ( ! WideDosDeviceName ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device index %d exceeds maximum", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Construct the device and DOS device names */
    Status = ConstructSoundDeviceNames(WideDeviceName,
                                       WideDosDeviceName,
                                       Index,
                                       &DeviceName,
                                       &DosDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        return Status;
    }
 
    DPRINT("Creating device %ws\n", DeviceName.Buffer);
 
    /* Now create the device */
    Status = IoCreateDevice(DriverObject,
                            ExtensionSize,
                            &DeviceName,
                            FILE_DEVICE_SOUND,
                            0,
                            FALSE,
                            DeviceObject);
 
    if ( ! NT_SUCCESS(Status) )
    {
        /* These will have been allocated by ConstructSoundDeviceNames */
        FreeUnicodeStringBuffer(&DeviceName);
        FreeUnicodeStringBuffer(&DosDeviceName);
 
        return Status;
    }
 
    DPRINT("Creating link %ws\n", DosDeviceName.Buffer);
 
    /* Create a symbolic link for the DOS deviec name */
    Status = IoCreateSymbolicLink(&DosDeviceName, &DeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        IoDeleteDevice(*DeviceObject);
 
        /* These will have been allocated by ConstructSoundDeviceNames */
        FreeUnicodeStringBuffer(&DeviceName);
        FreeUnicodeStringBuffer(&DosDeviceName);
 
        return Status;
    }
 
    return STATUS_SUCCESS;
}

Referenced by CreateSoundDeviceWithDefaultName().

CreateSoundDeviceWithDefaultName()

NTSTATUS CreateSoundDeviceWithDefaultName	(	IN PDRIVER_OBJECT	DriverObject,
		IN UCHAR	DeviceType,
		IN UCHAR	Index,
		IN ULONG	ExtensionSize,
		OUT PDEVICE_OBJECT *	DeviceObject
	)

Definition at line 349 of file devname.c.

{
    NTSTATUS Status;
    PCWSTR WideDeviceName = NULL;
    PCWSTR WideDosDeviceName = NULL;
 
    /* Check for NULL parameters */
    if ( ( ! DriverObject ) || ( ! DeviceObject ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device index %d exceeds maximum", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Look-up the default name based on the device type */
    Status = GetDefaultSoundDeviceNameBodies(DeviceType,
                                             &WideDeviceName,
                                             &WideDosDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        return Status;
    }
 
    /* Go create the device! */
    Status = CreateSoundDevice(DriverObject,
                               WideDeviceName,
                               WideDosDeviceName,
                               Index,
                               ExtensionSize,
                               DeviceObject);
 
    if ( ! NT_SUCCESS(Status) )
    {
        /* No clean-up to do */
        return Status;
    }
 
    return STATUS_SUCCESS;
}

DestroySoundDevice()

NTSTATUS DestroySoundDevice	(	IN PDEVICE_OBJECT	DeviceObject,
		IN PCWSTR	WideDosDeviceName,
		IN UCHAR	Index
	)

Definition at line 402 of file devname.c.

{
    NTSTATUS Status;
    UNICODE_STRING DosDeviceName;
 
    /* Check for NULL parameters */
    if ( ( ! WideDosDeviceName ) || ( ! DeviceObject ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device %d exceeds maximum", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    Status = ConstructDeviceName(WideDosDeviceName, Index, &DosDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        return Status;
    }
 
    DPRINT("Deleting symlink %ws\n", DosDeviceName.Buffer);
 
    Status = IoDeleteSymbolicLink(&DosDeviceName);
    DPRINT("Status of symlink deletion is 0x%08x\n", Status);
/*
    ASSERT(NT_SUCCESS(Status));
*/
 
    IoDeleteDevice(DeviceObject);
 
    return STATUS_SUCCESS;
}

Referenced by DestroySoundDeviceWithDefaultName().

DestroySoundDeviceWithDefaultName()

NTSTATUS DestroySoundDeviceWithDefaultName	(	IN PDEVICE_OBJECT	DeviceObject,
		IN UCHAR	DeviceType,
		IN UCHAR	Index
	)

Definition at line 445 of file devname.c.

{
    NTSTATUS Status;
    PCWSTR WideDosDeviceName = NULL;
 
    /* Check for NULL parameters */
    if ( ( ! DeviceObject ) )
    {
        DPRINT("Unexpected NULL parameter");
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Range-check */
    if ( Index >= SOUND_MAX_DEVICES )
    {
        DPRINT("Device index %d exceeds maximum", Index);
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Look-up the default name based on the device type */
    Status = GetDefaultSoundDeviceNameBodies(DeviceType,
                                             NULL,
                                             &WideDosDeviceName);
 
    if ( ! NT_SUCCESS(Status) )
    {
        return Status;
    }
 
    DPRINT("DOS device name at %p\n", WideDosDeviceName);
 
    DPRINT("DOS device name is based on %ws\n", WideDosDeviceName);
 
    return DestroySoundDevice(DeviceObject, WideDosDeviceName, Index);
}

FreeUnicodeStringBuffer()

VOID FreeUnicodeStringBuffer

(

IN PUNICODE_STRING

String

)

Definition at line 142 of file devname.c.

{
    ASSERT(String != NULL);
    ASSERT(String->Buffer != NULL);
 
    ExFreePool(String->Buffer);
 
    String->Buffer = NULL;
    String->Length = 0;
    String->MaximumLength = 0;
}

Referenced by ConstructSoundDeviceNames(), and CreateSoundDevice().

GetDefaultSoundDeviceNameBodies()

NTSTATUS GetDefaultSoundDeviceNameBodies	(	IN UCHAR	DeviceType,
		OUT PCWSTR *	DeviceNameBody,
		OUT PCWSTR *	DosDeviceNameBody
	)

Definition at line 167 of file devname.c.

{
    if ( ! IS_VALID_SOUND_DEVICE_TYPE(DeviceType) )
    {
        DPRINT("Invalid device type");
        return STATUS_INVALID_PARAMETER;
    }
 
    if ( DeviceNameBody )
    {
        DPRINT("Reporting device name\n");
        *DeviceNameBody = SoundDeviceNameBodies[DeviceType].DeviceName;
        DPRINT("%ws\n", *DeviceNameBody);
    }
 
    if ( DosDeviceNameBody )
    {
        DPRINT("Reporting DOS device name\n");
        *DosDeviceNameBody = SoundDeviceNameBodies[DeviceType].DosDeviceName;
        DPRINT("%ws\n", *DosDeviceNameBody);
    }
 
    return STATUS_SUCCESS;
}

Referenced by CreateSoundDeviceWithDefaultName(), and DestroySoundDeviceWithDefaultName().