C++ DevicePathNodeLength函数代码示例

/**
  Returns the size of a device path in bytes.

  This function returns the size, in bytes, of the device path data structure 
  specified by DevicePath including the end of device path node. If DevicePath 
  is NULL, then 0 is returned. If the length of the device path is bigger than
  MaxSize, also return 0 to indicate this is an invalidate device path.

  @param  DevicePath         A pointer to a device path data structure.
  @param  MaxSize            Max valid device path size. If big than this size, 
                             return error.
  
  @retval 0                  An invalid device path.
  @retval Others             The size of a device path in bytes.

**/
UINTN
BmGetDevicePathSizeEx (
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath,
  IN UINTN                           MaxSize
  )
{
  UINTN  Size;
  UINTN  NodeSize;

  if (DevicePath == NULL) {
    return 0;
  }

  //
  // Search for the end of the device path structure
  //
  Size = 0;
  while (!IsDevicePathEnd (DevicePath)) {
    NodeSize = DevicePathNodeLength (DevicePath);
    if (NodeSize == 0) {
      return 0;
    }
    Size += NodeSize;
    if (Size > MaxSize) {
      return 0;
    }
    DevicePath = NextDevicePathNode (DevicePath);
  }
  Size += DevicePathNodeLength (DevicePath);
  if (Size > MaxSize) {
    return 0;
  }

  return Size;
}

EFI_DEVICE_PATH *
UnpackDevicePath (
    IN EFI_DEVICE_PATH  *DevPath
    )
{
    EFI_DEVICE_PATH     *Src, *Dest, *NewPath;
    UINTN               Size;
    
    //
    // Walk device path and round sizes to valid boundries
    //    

    Src = DevPath;
    Size = 0;
    for (; ;) {
        Size += DevicePathNodeLength(Src);
        Size += ALIGN_SIZE(Size);

        if (IsDevicePathEnd(Src)) {
            break;
        }

        Src = NextDevicePathNode(Src);
    }


    //
    // Allocate space for the unpacked path
    //

    NewPath = AllocateZeroPool (Size);
    if (NewPath) {

        ASSERT (((UINTN)NewPath) % MIN_ALIGNMENT_SIZE == 0);

        //
        // Copy each node
        //

        Src = DevPath;
        Dest = NewPath;
        for (; ;) {
            Size = DevicePathNodeLength(Src);
            CopyMem (Dest, Src, Size);
            Size += ALIGN_SIZE(Size);
            SetDevicePathNodeLength (Dest, Size);
            Dest->Type |= EFI_DP_TYPE_UNPACKED;
            Dest = (EFI_DEVICE_PATH *) (((UINT8 *) Dest) + Size);

            if (IsDevicePathEnd(Src)) {
                break;
            }

            Src = NextDevicePathNode(Src);
        }
    }

    return NewPath;
}

/**
  Determine whether a given device path is valid.
  If DevicePath is NULL, then ASSERT().

  @param  DevicePath  A pointer to a device path data structure.
  @param  MaxSize     The maximum size of the device path data structure.

  @retval TRUE        DevicePath is valid.
  @retval FALSE       The length of any node node in the DevicePath is less
                      than sizeof (EFI_DEVICE_PATH_PROTOCOL).
  @retval FALSE       If MaxSize is not zero, the size of the DevicePath
                      exceeds MaxSize.
  @retval FALSE       If PcdMaximumDevicePathNodeCount is not zero, the node
                      count of the DevicePath exceeds PcdMaximumDevicePathNodeCount.
**/
BOOLEAN
EFIAPI
IsDevicePathValid (
  IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
  IN       UINTN                    MaxSize
  )
{
  UINTN Count;
  UINTN Size;
  UINTN NodeLength;

  ASSERT (DevicePath != NULL);

  if (MaxSize == 0) {
    MaxSize = MAX_UINTN;
  }

  //
  // Validate the input size big enough to touch the first node.
  //
  if (MaxSize < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {
    return FALSE;
  }

  for (Count = 0, Size = 0; !IsDevicePathEnd (DevicePath); DevicePath = NextDevicePathNode (DevicePath)) {
    NodeLength = DevicePathNodeLength (DevicePath);
    if (NodeLength < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {
      return FALSE;
    }

    if (NodeLength > MAX_UINTN - Size) {
      return FALSE;
    }
    Size += NodeLength;

    //
    // Validate next node before touch it.
    //
    if (Size > MaxSize - END_DEVICE_PATH_LENGTH ) {
      return FALSE;
    }

    if (PcdGet32 (PcdMaximumDevicePathNodeCount) > 0) {
      Count++;
      if (Count >= PcdGet32 (PcdMaximumDevicePathNodeCount)) {
        return FALSE;
      }
    }
  }

  //
  // Only return TRUE when the End Device Path node is valid.
  //
  return (BOOLEAN) (DevicePathNodeLength (DevicePath) == END_DEVICE_PATH_LENGTH);
}

/**
  Get the URI address string from the input device path.

  Caller need to free the buffer in the UriAddress pointer.
  
  @param[in]   FilePath         Pointer to the device path which contains a URI device path node.
  @param[out]  UriAddress       The URI address string extract from the device path.
  
  @retval EFI_SUCCESS            The URI string is returned.
  @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.

**/
EFI_STATUS
HttpBootParseFilePath (
  IN     EFI_DEVICE_PATH_PROTOCOL     *FilePath,
     OUT CHAR8                        **UriAddress
  )
{
  EFI_DEVICE_PATH_PROTOCOL  *TempDevicePath;
  URI_DEVICE_PATH           *UriDevicePath;
  CHAR8                     *Uri;
  UINTN                     UriStrLength;

  if (FilePath == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  *UriAddress = NULL;

  //
  // Extract the URI address from the FilePath
  //
  TempDevicePath = FilePath;
  while (!IsDevicePathEnd (TempDevicePath)) {
    if ((DevicePathType (TempDevicePath) == MESSAGING_DEVICE_PATH) &&
        (DevicePathSubType (TempDevicePath) == MSG_URI_DP)) {
      UriDevicePath = (URI_DEVICE_PATH*) TempDevicePath;
      //
      // UEFI Spec doesn't require the URI to be a NULL-terminated string
      // So we allocate a new buffer and always append a '\0' to it.
      //
      UriStrLength = DevicePathNodeLength (UriDevicePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL);
      if (UriStrLength == 0) {
        //
        // return a NULL UriAddress if it's a empty URI device path node.
        //
        break;
      }
      Uri = AllocatePool (UriStrLength + 1);
      if (Uri == NULL) {
        return EFI_OUT_OF_RESOURCES;
      }
      CopyMem (Uri, UriDevicePath->Uri, DevicePathNodeLength (UriDevicePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL));
      Uri[DevicePathNodeLength (UriDevicePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL)] = '\0';

      *UriAddress = Uri;
    }
    TempDevicePath = NextDevicePathNode (TempDevicePath);
  }

  return EFI_SUCCESS;
}

/**
  This function retrieves an SD card slot number based on the input device path.

  The GetSlotNumber() function retrieves slot number for the SD card specified by
  the DevicePath node. If DevicePath is NULL, EFI_INVALID_PARAMETER is returned.

  If DevicePath is not a device path node type that the SD Pass Thru driver supports,
  EFI_UNSUPPORTED is returned.

  @param[in]  This              A pointer to the EFI_SD_MMC_PASS_THRU_PROTOCOL instance.
  @param[in]  DevicePath        A pointer to the device path node that describes a SD
                                card on the SD controller.
  @param[out] Slot              On return, points to the slot number of an SD card on
                                the SD controller.

  @retval EFI_SUCCESS           SD card slot number is returned in Slot.
  @retval EFI_INVALID_PARAMETER Slot or DevicePath is NULL.
  @retval EFI_UNSUPPORTED       DevicePath is not a device path node type that the SD
                                Pass Thru driver supports.

**/
EFI_STATUS
EFIAPI
SdMmcPassThruGetSlotNumber (
  IN  EFI_SD_MMC_PASS_THRU_PROTOCOL          *This,
  IN  EFI_DEVICE_PATH_PROTOCOL               *DevicePath,
  OUT UINT8                                  *Slot
  )
{
  SD_MMC_HC_PRIVATE_DATA          *Private;
  SD_DEVICE_PATH                  *SdNode;
  EMMC_DEVICE_PATH                *EmmcNode;
  UINT8                           SlotNumber;

  if ((This == NULL) || (DevicePath == NULL) || (Slot == NULL)) {
    return EFI_INVALID_PARAMETER;
  }

  Private = SD_MMC_HC_PRIVATE_FROM_THIS (This);

  //
  // Check whether the DevicePath belongs to SD_DEVICE_PATH or EMMC_DEVICE_PATH
  //
  if ((DevicePath->Type != MESSAGING_DEVICE_PATH) ||
      ((DevicePath->SubType != MSG_SD_DP) &&
       (DevicePath->SubType != MSG_EMMC_DP)) ||
      (DevicePathNodeLength(DevicePath) != sizeof(SD_DEVICE_PATH)) ||
      (DevicePathNodeLength(DevicePath) != sizeof(EMMC_DEVICE_PATH))) {
    return EFI_UNSUPPORTED;
  }

  if (DevicePath->SubType == MSG_SD_DP) {
    SdNode = (SD_DEVICE_PATH *) DevicePath;
    SlotNumber = SdNode->SlotNumber;
  } else {
    EmmcNode = (EMMC_DEVICE_PATH *) DevicePath;
    SlotNumber = EmmcNode->SlotNumber;
  }

  if (SlotNumber >= SD_MMC_HC_MAX_SLOT) {
    return EFI_NOT_FOUND;
  }

  if (Private->Slot[SlotNumber].Enable) {
    *Slot = SlotNumber;
    return EFI_SUCCESS;
  } else {
    return EFI_NOT_FOUND;
  }
}

/**
  Determine whether a given device path is valid.
  If DevicePath is NULL, then ASSERT().

  @param  DevicePath  A pointer to a device path data structure.
  @param  MaxSize     The maximum size of the device path data structure.

  @retval TRUE        DevicePath is valid.
  @retval FALSE       The length of any node node in the DevicePath is less
                      than sizeof (EFI_DEVICE_PATH_PROTOCOL).
  @retval FALSE       If MaxSize is not zero, the size of the DevicePath
                      exceeds MaxSize.
  @retval FALSE       If PcdMaximumDevicePathNodeCount is not zero, the node
                      count of the DevicePath exceeds PcdMaximumDevicePathNodeCount.
**/
BOOLEAN
EFIAPI
IsDevicePathValid (
  IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
  IN       UINTN                    MaxSize
  )
{
  UINTN Count;
  UINTN Size;
  UINTN NodeLength;

  ASSERT (DevicePath != NULL);

  if (MaxSize == 0){
    MaxSize = MAX_UINTN;
  }

  Size = 0;
  Count = 0;

  while (MaxSize >= sizeof (EFI_DEVICE_PATH_PROTOCOL) &&
        (MaxSize - sizeof (EFI_DEVICE_PATH_PROTOCOL) >= Size) &&
        !IsDevicePathEnd (DevicePath)) {
    NodeLength = DevicePathNodeLength (DevicePath);
    if (NodeLength < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {
      return FALSE;
    }

    if (NodeLength > MAX_UINTN - Size) {
      return FALSE;
    }

    Size += NodeLength;

    if (PcdGet32 (PcdMaximumDevicePathNodeCount) > 0) {
      Count++;
      if (Count >= PcdGet32 (PcdMaximumDevicePathNodeCount)) {
        return FALSE;
      }
    }

    DevicePath = NextDevicePathNode (DevicePath);
  }

  //
  // Only return TRUE when the End Device Path node is valid.
  //
  return (BOOLEAN) (DevicePathNodeLength (DevicePath) == END_DEVICE_PATH_LENGTH);
}

static VOID
_DevPathIPv6 (
    IN OUT POOL_PRINT       *Str,
    IN VOID                 *DevPath
    )
{
    IPv6_DEVICE_PATH     *IP;

    IP = DevPath;
    CatPrint( Str , L"IPv6(") ;
    CatPrintIPv6( Str , & IP-> RemoteIpAddress ) ;
    CatPrint( Str , L",") ;
    CatPrintNetworkProtocol( Str, IP-> Protocol ) ;
    CatPrint( Str , L",%s," , IP-> IPAddressOrigin ?
        ( IP-> IPAddressOrigin == 1 ? L"StatelessAutoConfigure" :
        L"StatefulAutoConfigure" ) : L"Static" ) ;
    CatPrintIPv6( Str , & IP-> LocalIpAddress ) ;
    if ( DevicePathNodeLength( & IP-> Header ) == sizeof( IPv6_DEVICE_PATH ) ) {
        CatPrint( Str , L",") ;
        CatPrintIPv6( Str , & IP-> GatewayIpAddress ) ;
        CatPrint( Str , L",") ;
        CatPrint( Str , L"%d" , & IP-> PrefixLength ) ;
    }
    CatPrint( Str , L")") ;
}

static VOID
_DevPathMacAddr (
    IN OUT POOL_PRINT       *Str,
    IN VOID                 *DevPath
    )
{
    MAC_ADDR_DEVICE_PATH    *MAC;
    UINTN                   HwAddressSize;
    UINTN                   Index;

    MAC = DevPath;

    /* HwAddressSize = sizeof(EFI_MAC_ADDRESS); */
    HwAddressSize = DevicePathNodeLength( & MAC-> Header ) ;
    HwAddressSize -= sizeof( MAC-> Header ) ;
    HwAddressSize -= sizeof( MAC-> IfType ) ;
    if (MAC->IfType == 0x01 || MAC->IfType == 0x00) {
        HwAddressSize = 6;
    }
    
    CatPrint(Str, L"Mac(");

    for(Index = 0; Index < HwAddressSize; Index++) {
        CatPrint(Str, L"%02x",MAC->MacAddress.Addr[Index]);
    }
    if ( MAC-> IfType != 0 ) {
        CatPrint(Str, L",%d" , MAC-> IfType ) ;
    }
    CatPrint(Str, L")");
}

/**
  Returns the size of a device path in bytes.

  This function returns the size, in bytes, of the device path data structure
  specified by DevicePath including the end of device path node.
  If DevicePath is NULL or invalid, then 0 is returned.

  @param  DevicePath  A pointer to a device path data structure.

  @retval 0           If DevicePath is NULL or invalid.
  @retval Others      The size of a device path in bytes.

**/
UINTN
EFIAPI
UefiDevicePathLibGetDevicePathSize (
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
  )
{
  CONST EFI_DEVICE_PATH_PROTOCOL  *Start;

  if (DevicePath == NULL) {
    return 0;
  }

  if (!IsDevicePathValid (DevicePath, 0)) {
    return 0;
  }

  //
  // Search for the end of the device path structure
  //
  Start = DevicePath;
  while (!IsDevicePathEnd (DevicePath)) {
    DevicePath = NextDevicePathNode (DevicePath);
  }

  //
  // Compute the size and add back in the size of the end device path structure
  //
  return ((UINTN) DevicePath - (UINTN) Start) + DevicePathNodeLength (DevicePath);
}

EFI_DEVICE_PATH *
AppendDevicePathNode (
    IN EFI_DEVICE_PATH  *Src1,
    IN EFI_DEVICE_PATH  *Src2
    )
// Src1 may have multiple "instances" and each instance is appended
// Src2 is a signal device path node (without a terminator) that is
// appended to each instance is Src1.
{
    EFI_DEVICE_PATH     *Temp, *Eop;
    UINTN               Length;

    //
    // Build a Src2 that has a terminator on it
    //

    Length = DevicePathNodeLength(Src2);
    Temp = AllocatePool (Length + sizeof(EFI_DEVICE_PATH));
    if (!Temp) {
        return NULL;
    }

    CopyMem (Temp, Src2, Length);
    Eop = NextDevicePathNode(Temp); 
    SetDevicePathEndNode(Eop);

    //
    // Append device paths
    //

    Src1 = AppendDevicePath (Src1, Temp);
    FreePool (Temp);
    return Src1;
}

EFI_STATUS
BusDriver1BindingSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL    *This,
  IN EFI_HANDLE                     Controller,
  IN EFI_DEVICE_PATH_PROTOCOL       *RemainingDevicePath
  )
{
  EFI_STATUS        Status;
  EFI_DEV_PATH      *Node;

  if (RemainingDevicePath != NULL) {
    Node = (EFI_DEV_PATH *)RemainingDevicePath;
    if (Node->DevPath.Type != HARDWARE_DEVICE_PATH ||
        Node->DevPath.SubType != HW_VENDOR_DP ||
        DevicePathNodeLength(&Node->DevPath) != sizeof(VENDOR_DEVICE_PATH)) {
      return EFI_UNSUPPORTED;
    }
  }

  Status = gtBS->OpenProtocol (
                      Controller,
                      &mInterfaceFunctionTestProtocol1Guid,
                      NULL,
                      This->DriverBindingHandle,
                      Controller,
                      EFI_OPEN_PROTOCOL_TEST_PROTOCOL
                      );
  if (EFI_ERROR(Status)) {
    return EFI_UNSUPPORTED;
  }

  return EFI_SUCCESS;
}

EFIAPI
NextDevicePathNode (
  IN CONST VOID  *Node
  )
{
  ASSERT (Node != NULL);
  return (EFI_DEVICE_PATH_PROTOCOL *)((UINT8 *)(Node) + DevicePathNodeLength(Node));
}

// Compare device paths
static INTN CompareDevicePaths(CONST EFI_DEVICE_PATH *dp1, CONST EFI_DEVICE_PATH *dp2)
{
    if (dp1 == NULL || dp2 == NULL)
        return -1;

    while (1) {
        UINT8 type1, type2;
        UINT8 subtype1, subtype2;
        UINT16 len1, len2;
        INTN ret;

        type1 = DevicePathType(dp1);
        type2 = DevicePathType(dp2);

        if (type1 != type2)
                return (int) type2 - (int) type1;

        subtype1 = DevicePathSubType(dp1);
        subtype2 = DevicePathSubType(dp2);

        if (subtype1 != subtype2)
                return (int) subtype1 - (int) subtype2;

        len1 = DevicePathNodeLength(dp1);
        len2 = DevicePathNodeLength(dp2);
        if (len1 != len2)
                return (int) len1 - (int) len2;

        ret = CompareMem(dp1, dp2, len1);
        if (ret != 0)
                return ret;

        if (IsDevicePathEnd(dp1))
                break;

        dp1 = (EFI_DEVICE_PATH*) ((char *)dp1 + len1);
        dp2 = (EFI_DEVICE_PATH*) ((char *)dp2 + len2);
    }

    return 0;
}

static VOID
_DevPathIPv4 (
    IN OUT POOL_PRINT       *Str,
    IN VOID                 *DevPath
    )
{
    IPv4_DEVICE_PATH     *IP;
    BOOLEAN show ;

    IP = DevPath;
    CatPrint( Str , L"IPv4(") ;
    CatPrintIPv4( Str , & IP-> RemoteIpAddress ) ;
    CatPrint( Str , L",") ;
    CatPrintNetworkProtocol( Str , IP-> Protocol ) ;
    CatPrint( Str , L",%s" , IP-> StaticIpAddress ? L"Static" : L"DHCP" ) ;
    show = IsNotNullIPv4( & IP-> LocalIpAddress ) ;
    if ( ! show && DevicePathNodeLength( & IP-> Header ) == sizeof( IPv4_DEVICE_PATH ) ) {
        /* only version 2 includes gateway and netmask */
        show |= IsNotNullIPv4( & IP-> GatewayIpAddress ) ;
        show |= IsNotNullIPv4( & IP-> SubnetMask  ) ;
    }
    if ( show ) {
        CatPrint( Str , L"," ) ;
        CatPrintIPv4( Str , & IP-> LocalIpAddress ) ;
        if ( DevicePathNodeLength( & IP-> Header ) == sizeof( IPv4_DEVICE_PATH ) ) {
            /* only version 2 includes gateway and netmask */
            show = IsNotNullIPv4( & IP-> GatewayIpAddress ) ;
            show |= IsNotNullIPv4( & IP-> SubnetMask ) ;
            if ( show ) {
                CatPrint( Str , L",") ;
                CatPrintIPv4( Str , & IP-> GatewayIpAddress ) ;
                if ( IsNotNullIPv4( & IP-> SubnetMask ) ) {
                    CatPrint( Str , L",") ;
                    CatPrintIPv4( Str , & IP-> SubnetMask ) ;
                }
            }
        }
    }
    CatPrint( Str , L")") ;
}

/**
  Check to see if this driver supports the given controller

  @param  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
  @param  Controller           The handle of the controller to test.
  @param  RemainingDevicePath  A pointer to the remaining portion of a device path.

  @return EFI_SUCCESS          This driver can support the given controller

**/
EFI_STATUS
EFIAPI
SerialControllerDriverSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL    *This,
  IN EFI_HANDLE                     Controller,
  IN EFI_DEVICE_PATH_PROTOCOL       *RemainingDevicePath
  )

{
  EFI_STATUS                                Status;
  UART_DEVICE_PATH                          *Uart;
  UART_FLOW_CONTROL_DEVICE_PATH             *FlowControl;

  //
  // Test RemainingDevicePath
  //
  if ((RemainingDevicePath != NULL) && !IsDevicePathEnd (RemainingDevicePath)) {
    Status = EFI_UNSUPPORTED;

    Uart = SkipControllerDevicePathNode (RemainingDevicePath, NULL, NULL);
    if (DevicePathType (Uart) != MESSAGING_DEVICE_PATH ||
        DevicePathSubType (Uart) != MSG_UART_DP ||
        DevicePathNodeLength (Uart) != sizeof (UART_DEVICE_PATH)
        ) {
      return EFI_UNSUPPORTED;
    }

    //
    // Do a rough check because Clock Rate is unknown until DriverBindingStart()
    //
    if (!VerifyUartParameters (0, Uart->BaudRate, Uart->DataBits, Uart->Parity, Uart->StopBits, NULL, NULL)) {
      return EFI_UNSUPPORTED;
    }

    FlowControl = (UART_FLOW_CONTROL_DEVICE_PATH *) NextDevicePathNode (Uart);
    if (IsUartFlowControlDevicePathNode (FlowControl)) {
      //
      // If the second node is Flow Control Node,
      //   return error when it request other than hardware flow control.
      //
      if ((ReadUnaligned32 (&FlowControl->FlowControlMap) & ~UART_FLOW_CONTROL_HARDWARE) != 0) {
        return EFI_UNSUPPORTED;
      }
    }
  }

  Status = IsSioSerialController (Controller);
  if (EFI_ERROR (Status)) {
    Status = IsPciSerialController (Controller);
  }
  return Status;
}