audk/FatPkg/EnhancedFatDxe/OpenVolume.c

/** @file
  OpenVolume() function of Simple File System Protocol.

Copyright (c) 2005 - 2013, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "Fat.h"

/**

  Implements Simple File System Protocol interface function OpenVolume().

  @param  This                  - Calling context.
  @param  File                  - the Root Directory of the volume.

  @retval EFI_OUT_OF_RESOURCES  - Can not allocate the memory.
  @retval EFI_VOLUME_CORRUPTED  - The FAT type is error.
  @retval EFI_SUCCESS           - Open the volume successfully.

**/
EFI_STATUS
EFIAPI
FatOpenVolume (
  IN  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL  *This,
  OUT EFI_FILE_PROTOCOL                **File
  )
{
  EFI_STATUS  Status;
  FAT_VOLUME  *Volume;
  FAT_IFILE   *IFile;

  Volume = VOLUME_FROM_VOL_INTERFACE (This);
  FatAcquireLock ();

  //
  // Open Root file
  //
  Status = FatOpenDirEnt (NULL, &Volume->RootDirEnt);
  if (EFI_ERROR (Status)) {
    goto Done;
  }

  //
  // Open a new instance to the root
  //
  Status = FatAllocateIFile (Volume->Root, &IFile);
  if (!EFI_ERROR (Status)) {
    *File = &IFile->Handle;
  }

Done:

  Status = FatCleanupVolume (Volume, Volume->Root, Status, NULL);
  FatReleaseLock ();

  return Status;
}