audk/MdePkg/Include/Protocol/LoadFile.h

/** @file
  Load File protocol as defined in the UEFI 2.0 specification.

  The load file protocol exists to supports the addition of new boot devices, 
  and to support booting from devices that do not map well to file system. 
  Network boot is done via a LoadFile protocol.

  UEFI 2.0 can boot from any device that produces a LoadFile protocol.

Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available under 
the terms and conditions of the BSD License that accompanies this distribution.  
The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.                                          
    
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             

**/

#ifndef __EFI_LOAD_FILE_PROTOCOL_H__
#define __EFI_LOAD_FILE_PROTOCOL_H__

#define EFI_LOAD_FILE_PROTOCOL_GUID \
  { \
    0x56EC3091, 0x954C, 0x11d2, {0x8E, 0x3F, 0x00, 0xA0, 0xC9, 0x69, 0x72, 0x3B } \
  }

///
/// Protocol Guid defined by EFI1.1.
///
#define LOAD_FILE_PROTOCOL EFI_LOAD_FILE_PROTOCOL_GUID

typedef struct _EFI_LOAD_FILE_PROTOCOL EFI_LOAD_FILE_PROTOCOL;

///
/// Backward-compatible with EFI1.1
/// 
typedef EFI_LOAD_FILE_PROTOCOL  EFI_LOAD_FILE_INTERFACE;

/**
  Causes the driver to load a specified file.

  @param  This       Protocol instance pointer.
  @param  FilePath   The device specific path of the file to load.
  @param  BootPolicy If TRUE, indicates that the request originates from the
                     boot manager is attempting to load FilePath as a boot
                     selection. If FALSE, then FilePath must match as exact file
                     to be loaded.
  @param  BufferSize On input the size of Buffer in bytes. On output with a return
                     code of EFI_SUCCESS, the amount of data transferred to
                     Buffer. On output with a return code of EFI_BUFFER_TOO_SMALL,
                     the size of Buffer required to retrieve the requested file.
  @param  Buffer     The memory buffer to transfer the file to. IF Buffer is NULL,
                     then the size of the requested file is returned in
                     BufferSize.

  @retval EFI_SUCCESS           The file was loaded.
  @retval EFI_UNSUPPORTED       The device does not support the provided BootPolicy
  @retval EFI_INVALID_PARAMETER FilePath is not a valid device path, or
                                BufferSize is NULL.
  @retval EFI_NO_MEDIA          No medium was present to load the file.
  @retval EFI_DEVICE_ERROR      The file was not loaded due to a device error.
  @retval EFI_NO_RESPONSE       The remote system did not respond.
  @retval EFI_NOT_FOUND         The file was not found.
  @retval EFI_ABORTED           The file load process was manually cancelled.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_LOAD_FILE)(
  IN EFI_LOAD_FILE_PROTOCOL           *This,
  IN EFI_DEVICE_PATH_PROTOCOL         *FilePath,
  IN BOOLEAN                          BootPolicy,
  IN OUT UINTN                        *BufferSize,
  IN VOID                             *Buffer OPTIONAL
  );

///
/// The EFI_LOAD_FILE_PROTOCOL is a simple protocol used to obtain files from arbitrary devices.
///
struct _EFI_LOAD_FILE_PROTOCOL {
  EFI_LOAD_FILE LoadFile;
};

extern EFI_GUID gEfiLoadFileProtocolGuid;

#endif