chrome/installer/util/delete_reg_key_work_item.cc

   1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/installer/util/delete_reg_key_work_item.h"
   6
   7 #include <shlwapi.h>
   8
   9 #include "base/logging.h"
  10 #include "base/win/registry.h"
  11
  12 using base::win::RegKey;
  13
  14 DeleteRegKeyWorkItem::~DeleteRegKeyWorkItem() {
  15 }
  16
  17 DeleteRegKeyWorkItem::DeleteRegKeyWorkItem(HKEY predefined_root,
  18                                            const std::wstring& path)
  19     : predefined_root_(predefined_root),
  20       path_(path) {
  21   DCHECK(predefined_root);
  22   // It's a safe bet that we don't want to delete one of the root trees.
  23   DCHECK(!path.empty());
  24 }
  25
  26 bool DeleteRegKeyWorkItem::Do() {
  27   if (path_.empty())
  28     return false;
  29
  30   RegistryKeyBackup backup;
  31
  32   // Only try to make a backup if we're not configured to ignore failures.
  33   if (!ignore_failure_) {
  34     if (!backup.Initialize(predefined_root_, path_.c_str())) {
  35       LOG(ERROR) << "Failed to backup destination for registry key copy.";
  36       return false;
  37     }
  38   }
  39
  40   // Delete the key.
  41   LONG result = SHDeleteKey(predefined_root_, path_.c_str());
  42   if (result != ERROR_SUCCESS && result != ERROR_FILE_NOT_FOUND) {
  43     LOG(ERROR) << "Failed to delete key at " << path_ << ", result: "
  44                << result;
  45     return ignore_failure_;
  46   }
  47
  48   // We've succeeded, so remember any backup we may have made.
  49   backup_.swap(backup);
  50
  51   return true;
  52 }
  53
  54 void DeleteRegKeyWorkItem::Rollback() {
  55   if (ignore_failure_)
  56     return;
  57
  58   // Delete anything in the key before restoring the backup in case someone else
  59   // put new data in the key after Do().
  60   LONG result = SHDeleteKey(predefined_root_, path_.c_str());
  61   if (result != ERROR_SUCCESS && result != ERROR_FILE_NOT_FOUND) {
  62     LOG(ERROR) << "Failed to delete key at " << path_ << " in rollback, "
  63                   "result: " << result;
  64   }
  65
  66   // Restore the old contents.  The restoration takes on its default security
  67   // attributes; any custom attributes are lost.
  68   if (!backup_.WriteTo(predefined_root_, path_.c_str()))
  69     LOG(ERROR) << "Failed to restore key in rollback.";
  70 }