FatPkg/EnhancedFatDxe/Delete.c

   1 /** @file
   2   Function that deletes a file.
   3
   4 Copyright (c) 2005 - 2013, Intel Corporation. All rights reserved.<BR>
   5 SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7
   8 **/
   9
  10 #include "Fat.h"
  11
  12 /**
  13
  14   Deletes the file & Closes the file handle.
  15
  16   @param  FHand                    - Handle to the file to delete.
  17
  18   @retval EFI_SUCCESS              - Delete the file successfully.
  19   @retval EFI_WARN_DELETE_FAILURE  - Fail to delete the file.
  20
  21 **/
  22 EFI_STATUS
  23 EFIAPI
  24 FatDelete (
  25   IN EFI_FILE_PROTOCOL  *FHand
  26   )
  27 {
  28   FAT_IFILE   *IFile;
  29   FAT_OFILE   *OFile;
  30   FAT_DIRENT  *DirEnt;
  31   EFI_STATUS  Status;
  32   UINTN       Round;
  33
  34   IFile = IFILE_FROM_FHAND (FHand);
  35   OFile = IFile->OFile;
  36
  37   FatWaitNonblockingTask (IFile);
  38
  39   //
  40   // Lock the volume
  41   //
  42   FatAcquireLock ();
  43
  44   //
  45   // If the file is read-only, then don't delete it
  46   //
  47   if (IFile->ReadOnly) {
  48     Status = EFI_WRITE_PROTECTED;
  49     goto Done;
  50   }
  51
  52   //
  53   // If the file is the root dir, then don't delete it
  54   //
  55   if (OFile->Parent == NULL) {
  56     Status = EFI_ACCESS_DENIED;
  57     goto Done;
  58   }
  59
  60   //
  61   // If the file has a permanent error, skip the delete
  62   //
  63   Status = OFile->Error;
  64   if (!EFI_ERROR (Status)) {
  65     //
  66     // If this is a directory, make sure it's empty before
  67     // allowing it to be deleted
  68     //
  69     if (OFile->ODir != NULL) {
  70       //
  71       // We do not allow to delete nonempty directory
  72       //
  73       FatResetODirCursor (OFile);
  74       for (Round = 0; Round < 3; Round++) {
  75         Status = FatGetNextDirEnt (OFile, &DirEnt);
  76         if ((EFI_ERROR (Status)) ||
  77             ((Round < 2) && ((DirEnt == NULL) || !FatIsDotDirEnt (DirEnt))) ||
  78             ((Round == 2) && (DirEnt != NULL))
  79             )
  80         {
  81           Status = EFI_ACCESS_DENIED;
  82           goto Done;
  83         }
  84       }
  85     }
  86
  87     //
  88     // Return the file's space by setting its size to 0
  89     //
  90     FatTruncateOFile (OFile, 0);
  91     //
  92     // Free the directory entry for this file
  93     //
  94     Status = FatRemoveDirEnt (OFile->Parent, OFile->DirEnt);
  95     if (EFI_ERROR (Status)) {
  96       goto Done;
  97     }
  98
  99     //
 100     // Set a permanent error for this OFile in case there
 101     // are still opened IFiles attached
 102     //
 103     OFile->Error = EFI_NOT_FOUND;
 104   } else if (OFile->Error == EFI_NOT_FOUND) {
 105     Status = EFI_SUCCESS;
 106   }
 107
 108 Done:
 109   //
 110   // Always close the handle
 111   //
 112   FatIFileClose (IFile);
 113   //
 114   // Done
 115   //
 116   Status = FatCleanupVolume (OFile->Volume, NULL, Status, NULL);
 117   FatReleaseLock ();
 118
 119   if (EFI_ERROR (Status)) {
 120     Status = EFI_WARN_DELETE_FAILURE;
 121   }
 122
 123   return Status;
 124 }