FatPkg/EnhancedFatDxe/Delete.c

   1 /*++
   2
   3 Copyright (c) 2005 - 2013, Intel Corporation. All rights reserved.<BR>
   4 This program and the accompanying materials are licensed and made available
   5 under the terms and conditions of the BSD License which accompanies this
   6 distribution. The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12
  13 Module Name:
  14
  15   delete.c
  16
  17 Abstract:
  18
  19   Function that deletes a file
  20
  21 Revision History
  22
  23 --*/
  24
  25 #include "Fat.h"
  26
  27 EFI_STATUS
  28 EFIAPI
  29 FatDelete (
  30   IN EFI_FILE_PROTOCOL  *FHand
  31   )
  32 /*++
  33
  34 Routine Description:
  35
  36   Deletes the file & Closes the file handle.
  37
  38 Arguments:
  39
  40   FHand                    - Handle to the file to delete.
  41
  42 Returns:
  43
  44   EFI_SUCCESS              - Delete the file successfully.
  45   EFI_WARN_DELETE_FAILURE  - Fail to delete the file.
  46
  47 --*/
  48 {
  49   FAT_IFILE   *IFile;
  50   FAT_OFILE   *OFile;
  51   FAT_DIRENT  *DirEnt;
  52   EFI_STATUS  Status;
  53   UINTN       Round;
  54
  55   IFile = IFILE_FROM_FHAND (FHand);
  56   OFile = IFile->OFile;
  57
  58   FatWaitNonblockingTask (IFile);
  59
  60   //
  61   // Lock the volume
  62   //
  63   FatAcquireLock ();
  64
  65   //
  66   // If the file is read-only, then don't delete it
  67   //
  68   if (IFile->ReadOnly) {
  69     Status = EFI_WRITE_PROTECTED;
  70     goto Done;
  71   }
  72   //
  73   // If the file is the root dir, then don't delete it
  74   //
  75   if (OFile->Parent == NULL) {
  76     Status = EFI_ACCESS_DENIED;
  77     goto Done;
  78   }
  79   //
  80   // If the file has a permanant error, skip the delete
  81   //
  82   Status = OFile->Error;
  83   if (!EFI_ERROR (Status)) {
  84     //
  85     // If this is a directory, make sure it's empty before
  86     // allowing it to be deleted
  87     //
  88     if (OFile->ODir != NULL) {
  89       //
  90       // We do not allow to delete nonempty directory
  91       //
  92       FatResetODirCursor (OFile);
  93       for (Round = 0; Round < 3; Round++) {
  94         Status = FatGetNextDirEnt (OFile, &DirEnt);
  95         if ((EFI_ERROR (Status)) ||
  96             ((Round < 2) && (DirEnt == NULL || !FatIsDotDirEnt (DirEnt))) ||
  97             ((Round == 2) && (DirEnt != NULL))
  98             ) {
  99           Status = EFI_ACCESS_DENIED;
 100           goto Done;
 101         }
 102       }
 103     }
 104     //
 105     // Return the file's space by setting its size to 0
 106     //
 107     FatTruncateOFile (OFile, 0);
 108     //
 109     // Free the directory entry for this file
 110     //
 111     Status = FatRemoveDirEnt (OFile->Parent, OFile->DirEnt);
 112     if (EFI_ERROR (Status)) {
 113       goto Done;
 114     }
 115     //
 116     // Set a permanent error for this OFile in case there
 117     // are still opened IFiles attached
 118     //
 119     OFile->Error = EFI_NOT_FOUND;
 120   } else if (OFile->Error == EFI_NOT_FOUND) {
 121     Status = EFI_SUCCESS;
 122   }
 123
 124 Done:
 125   //
 126   // Always close the handle
 127   //
 128   FatIFileClose (IFile);
 129   //
 130   // Done
 131   //
 132   Status = FatCleanupVolume (OFile->Volume, NULL, Status, NULL);
 133   FatReleaseLock ();
 134
 135   if (EFI_ERROR (Status)) {
 136     Status = EFI_WARN_DELETE_FAILURE;
 137   }
 138
 139   return Status;
 140 }