FatPkg/EnhancedFatDxe/Delete.c

   1 /*++
   2
   3 Copyright (c) 2005, Intel Corporation
   4 All rights reserved. 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  *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   //
  59   // Lock the volume
  60   //
  61   FatAcquireLock ();
  62
  63   //
  64   // If the file is read-only, then don't delete it
  65   //
  66   if (IFile->ReadOnly) {
  67     Status = EFI_WRITE_PROTECTED;
  68     goto Done;
  69   }
  70   //
  71   // If the file is the root dir, then don't delete it
  72   //
  73   if (OFile->Parent == NULL) {
  74     Status = EFI_ACCESS_DENIED;
  75     goto Done;
  76   }
  77   //
  78   // If the file has a permanant error, skip the delete
  79   //
  80   Status = OFile->Error;
  81   if (!EFI_ERROR (Status)) {
  82     //
  83     // If this is a directory, make sure it's empty before
  84     // allowing it to be deleted
  85     //
  86     if (OFile->ODir != NULL) {
  87       //
  88       // We do not allow to delete nonempty directory
  89       //
  90       FatResetODirCursor (OFile);
  91       for (Round = 0; Round < 3; Round++) {
  92         Status = FatGetNextDirEnt (OFile, &DirEnt);
  93         if ((EFI_ERROR (Status)) ||
  94             ((Round < 2) && (DirEnt == NULL || !FatIsDotDirEnt (DirEnt))) ||
  95             ((Round == 2) && (DirEnt != NULL))
  96             ) {
  97           Status = EFI_ACCESS_DENIED;
  98           goto Done;
  99         }
 100       }
 101     }
 102     //
 103     // Return the file's space by setting its size to 0
 104     //
 105     FatTruncateOFile (OFile, 0);
 106     //
 107     // Free the directory entry for this file
 108     //
 109     Status = FatRemoveDirEnt (OFile->Parent, OFile->DirEnt);
 110     if (EFI_ERROR (Status)) {
 111       goto Done;
 112     }
 113     //
 114     // Set a permanent error for this OFile in case there
 115     // are still opened IFiles attached
 116     //
 117     OFile->Error = EFI_NOT_FOUND;
 118   } else if (OFile->Error == EFI_NOT_FOUND) {
 119     Status = EFI_SUCCESS;
 120   }
 121
 122 Done:
 123   //
 124   // Always close the handle
 125   //
 126   FatIFileClose (IFile);
 127   //
 128   // Done
 129   //
 130   Status = FatCleanupVolume (OFile->Volume, NULL, Status);
 131   FatReleaseLock ();
 132
 133   if (EFI_ERROR (Status)) {
 134     Status = EFI_WARN_DELETE_FAILURE;
 135   }
 136
 137   return Status;
 138 }