imagefile.c

EFI BIOS是Intel提出的下一代的BIOS标准。这里上传的Edk源代码是EFI BIOS源代码中的与平台无关部分的代码

/*++

Copyright (c) 2004 - 2006, Intel Corporation                                                         
All rights reserved. This program and the accompanying materials                          
are licensed and made available under the terms and conditions of the BSD License         
which 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.             

Module Name:
  
  ImageFile.c


Abstract:

  


Revision History

--*/

#include "Image.h"
#include "DxeCore.h"


VOID
CoreDevicePathToFileName (
  IN  FILEPATH_DEVICE_PATH      *FilePath,
  OUT CHAR16                    **String
  );



EFI_STATUS
CoreOpenImageFile (
  IN BOOLEAN                        BootPolicy,
  IN VOID                           *SourceBuffer   OPTIONAL,
  IN UINTN                          SourceSize,
  IN OUT EFI_DEVICE_PATH_PROTOCOL   *FilePath,
  OUT EFI_HANDLE                    *DeviceHandle,
  IN IMAGE_FILE_HANDLE              *ImageFileHandle,
  OUT UINT32                        *AuthenticationStatus
  )
/*++

Routine Description:

    Opens a file for (simple) reading.  The simple read abstraction
    will access the file either from a memory copy, from a file
    system interface, or from the load file interface.

Arguments:

  BootPolicy    - Policy for Open Image File.
  SourceBuffer  - Pointer to the memory location containing copy
                  of the image to be loaded.
  SourceSize    - The size in bytes of SourceBuffer.
  FilePath      - The specific file path from which the image is loaded
  DeviceHandle  - Pointer to the return device handle.
  ImageFileHandle      - Pointer to the image file handle.
  AuthenticationStatus - Pointer to a caller-allocated UINT32 in which the authentication status is returned. 
    
Returns:

    EFI_SUCCESS     - Image file successfully opened.
    
    EFI_LOAD_ERROR  - If the caller passed a copy of the file, and SourceSize is 0.
    
    EFI_INVALID_PARAMETER   - File path is not valid.
    
    EFI_NOT_FOUND   - File not found.

--*/
{
  EFI_STATUS                        Status;
  EFI_DEVICE_PATH_PROTOCOL          *TempFilePath;
  FILEPATH_DEVICE_PATH              *FilePathNode;
  MEDIA_FW_VOL_FILEPATH_DEVICE_PATH *FwVolFilePathNode;
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL   *Volume;
  EFI_FILE_HANDLE                   FileHandle;
  EFI_FILE_HANDLE                   LastHandle;
  EFI_LOAD_FILE_PROTOCOL            *LoadFile;
  EFI_FIRMWARE_VOLUME_PROTOCOL      *FwVol;
  EFI_SECTION_TYPE                  SectionType;
  UINT8                             *Pe32Buffer;
  UINTN                             Pe32BufferSize;
  EFI_FV_FILETYPE                   Type;
  EFI_FV_FILE_ATTRIBUTES            Attrib;
  EFI_FILE_INFO                     *FileInfo;
  UINTN                             FileInfoSize;
  EFI_GUID                          *NameGuid;

  *AuthenticationStatus = 0;
  EfiCommonLibZeroMem (ImageFileHandle, sizeof (IMAGE_FILE_HANDLE));
  ImageFileHandle->Signature = IMAGE_FILE_HANDLE_SIGNATURE;

  //
  // If the caller passed a copy of the file, then just use it
  //
  if (SourceBuffer != NULL) {
    ImageFileHandle->Source     = SourceBuffer;
    ImageFileHandle->SourceSize = SourceSize;
    *DeviceHandle     = NULL;
    if (SourceSize > 0) {
      Status = EFI_SUCCESS;
    } else {
      Status = EFI_LOAD_ERROR;
    }
    goto Done;
  }

  //
  // Make sure FilePath is valid
  //
  if (FilePath == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Check to see if it's in a Firmware Volume
  //
  FwVolFilePathNode = (MEDIA_FW_VOL_FILEPATH_DEVICE_PATH *)FilePath;
  Status = CoreDevicePathToInterface (
            &gEfiFirmwareVolumeProtocolGuid, 
            (EFI_DEVICE_PATH_PROTOCOL **)&FwVolFilePathNode, 
            (VOID*)&FwVol, 
            DeviceHandle
            );
  if (!EFI_ERROR (Status)) {
    //
    // For FwVol File system there is only a single file name that is a GUID.
    //
    NameGuid = CoreGetNameGuidFromFwVolDevicePathNode (FwVolFilePathNode);
	if (NameGuid != NULL) {

      SectionType = EFI_SECTION_PE32;
      Pe32Buffer  = NULL;
      Status = FwVol->ReadSection (
                        FwVol, 
                        &FwVolFilePathNode->NameGuid,  
                        SectionType,   
                        0,
                        &Pe32Buffer,
                        &Pe32BufferSize,
                        AuthenticationStatus
                        );
      if (EFI_ERROR (Status)) {
        //
        // Try a raw file, since a PE32 SECTION does not exist
        //
        if (Pe32Buffer != NULL) {
          CoreFreePool (Pe32Buffer);
          *AuthenticationStatus = 0;
        }
        Pe32Buffer = NULL;
        Status = FwVol->ReadFile (
                          FwVol, 
                          &FwVolFilePathNode->NameGuid, 
                          &Pe32Buffer,
                          &Pe32BufferSize,
                          &Type,
                          &Attrib,
                          AuthenticationStatus
                          );
      }
            
      if (!EFI_ERROR (Status)) {
        //
        // One of the reads passed so we are done
        //
        ImageFileHandle->Source = Pe32Buffer;
        ImageFileHandle->SourceSize = Pe32BufferSize;
        ImageFileHandle->FreeBuffer = TRUE;
        goto Done;
      }
    }
  }

  //
  // Attempt to access the file via a file system interface
  //
  FilePathNode = (FILEPATH_DEVICE_PATH *) FilePath;
  Status = CoreDevicePathToInterface (
            &gEfiSimpleFileSystemProtocolGuid, 
            (EFI_DEVICE_PATH_PROTOCOL **)&FilePathNode, 
            (VOID*)&Volume, 
            DeviceHandle
            );
  if (!EFI_ERROR (Status)) {
    //
    // Open the Volume to get the File System handle
    //
    Status = Volume->OpenVolume (Volume, &FileHandle);
    if (!EFI_ERROR (Status)) {
     
      //
      // Parse each MEDIA_FILEPATH_DP node. There may be more than one, since the
      //  directory information and filename can be seperate. The goal is to inch
      //  our way down each device path node and close the previous node
      //
      while (!IsDevicePathEnd (&FilePathNode->Header)) {
        if (DevicePathType (&FilePathNode->Header) != MEDIA_DEVICE_PATH ||
            DevicePathSubType (&FilePathNode->Header) != MEDIA_FILEPATH_DP) {
          Status = EFI_UNSUPPORTED;
        }

        if (EFI_ERROR (Status)) {
          //
          // Exit loop on Error
          //
          break;
        }

        LastHandle = FileHandle;
        FileHandle = NULL;
        Status = LastHandle->Open (
                              LastHandle,
                              &FileHandle,
                              FilePathNode->PathName,
                              EFI_FILE_MODE_READ,
                              0
                              );

        //
        // Close the previous node
        //
        LastHandle->Close (LastHandle);

        FilePathNode = (FILEPATH_DEVICE_PATH *) NextDevicePathNode (&FilePathNode->Header);
      }

      if (!EFI_ERROR (Status)) {
        //
        // We have found the file. Now we need to read it. Before we can read the file we need to
        // figure out how big the file is.
        //
        FileInfo = NULL;
        FileInfoSize = sizeof (EFI_FILE_INFO);
        while (CoreGrowBuffer (&Status, &FileInfo, FileInfoSize)) {
          //
          // Automatically allocate buffer of the correct size and make the call
          //
          Status = FileHandle->GetInfo (
                                FileHandle,
                                &gEfiFileInfoGuid,
                                &FileInfoSize,
                                FileInfo                               
                                );
        }
        if (!EFI_ERROR (Status)) {
          //
          // Allocate space for the file
          //
          ImageFileHandle->Source = CoreAllocateBootServicesPool ((UINTN)FileInfo->FileSize);
          if (ImageFileHandle->Source != NULL) {
            //
            // Read the file into the buffer we allocated
            //
            ImageFileHandle->SourceSize = (UINTN)FileInfo->FileSize;
            ImageFileHandle->FreeBuffer = TRUE;
            Status = FileHandle->Read (FileHandle, &ImageFileHandle->SourceSize, ImageFileHandle->Source);

            //
            // Close the file since we are done
            //
            FileHandle->Close (FileHandle);
          } else {
            Status = EFI_OUT_OF_RESOURCES;
          }

          goto Done;
        }
      }
    }
  } 


  //
  // Try LoadFile style
  //

  TempFilePath = FilePath;