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   // If the file is the root dir, then don't delete it
  53   //
  54   if (OFile->Parent == NULL) {
  55     Status = EFI_ACCESS_DENIED;
  56     goto Done;
  57   }
  58   //
  59   // If the file has a permanant error, skip the delete
  60   //
  61   Status = OFile->Error;
  62   if (!EFI_ERROR (Status)) {
  63     //
  64     // If this is a directory, make sure it's empty before
  65     // allowing it to be deleted
  66     //
  67     if (OFile->ODir != NULL) {
  68       //
  69       // We do not allow to delete nonempty directory
  70       //
  71       FatResetODirCursor (OFile);
  72       for (Round = 0; Round < 3; Round++) {
  73         Status = FatGetNextDirEnt (OFile, &DirEnt);
  74         if ((EFI_ERROR (Status)) ||
  75             ((Round < 2) && (DirEnt == NULL || !FatIsDotDirEnt (DirEnt))) ||
  76             ((Round == 2) && (DirEnt != NULL))
  77             ) {
  78           Status = EFI_ACCESS_DENIED;
  79           goto Done;
  80         }
  81       }
  82     }
  83     //
  84     // Return the file's space by setting its size to 0
  85     //
  86     FatTruncateOFile (OFile, 0);
  87     //
  88     // Free the directory entry for this file
  89     //
  90     Status = FatRemoveDirEnt (OFile->Parent, OFile->DirEnt);
  91     if (EFI_ERROR (Status)) {
  92       goto Done;
  93     }
  94     //
  95     // Set a permanent error for this OFile in case there
  96     // are still opened IFiles attached
  97     //
  98     OFile->Error = EFI_NOT_FOUND;
  99   } else if (OFile->Error == EFI_NOT_FOUND) {
 100     Status = EFI_SUCCESS;
 101   }
 102
 103 Done:
 104   //
 105   // Always close the handle
 106   //
 107   FatIFileClose (IFile);
 108   //
 109   // Done
 110   //
 111   Status = FatCleanupVolume (OFile->Volume, NULL, Status, NULL);
 112   FatReleaseLock ();
 113
 114   if (EFI_ERROR (Status)) {
 115     Status = EFI_WARN_DELETE_FAILURE;
 116   }
 117
 118   return Status;
 119 }