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 #include "chrome/installer/util/install_util.h"
  12
  13 using base::win::RegKey;
  14
  15 DeleteRegKeyWorkItem::~DeleteRegKeyWorkItem() {
  16 }
  17
  18 DeleteRegKeyWorkItem::DeleteRegKeyWorkItem(HKEY predefined_root,
  19                                            const std::wstring& path,
  20                                            REGSAM wow64_access)
  21     : predefined_root_(predefined_root),
  22       path_(path),
  23       wow64_access_(wow64_access) {
  24   DCHECK(predefined_root);
  25   // It's a safe bet that we don't want to delete one of the root trees.
  26   DCHECK(!path.empty());
  27   DCHECK(wow64_access == 0 ||
  28          wow64_access == KEY_WOW64_32KEY ||
  29          wow64_access == KEY_WOW64_64KEY);
  30 }
  31
  32 bool DeleteRegKeyWorkItem::Do() {
  33   if (path_.empty())
  34     return false;
  35
  36   RegistryKeyBackup backup;
  37
  38   // Only try to make a backup if we're not configured to ignore failures.
  39   if (!ignore_failure_) {
  40     if (!backup.Initialize(predefined_root_, path_.c_str(), wow64_access_)) {
  41       LOG(ERROR) << "Failed to backup destination for registry key copy.";
  42       return false;
  43     }
  44   }
  45
  46   // Delete the key.
  47   if (!InstallUtil::DeleteRegistryKey(
  48           predefined_root_, path_.c_str(), wow64_access_)) {
  49     return ignore_failure_;
  50   }
  51
  52   // We've succeeded, so remember any backup we may have made.
  53   backup_.swap(backup);
  54
  55   return true;
  56 }
  57
  58 void DeleteRegKeyWorkItem::Rollback() {
  59   if (ignore_failure_)
  60     return;
  61
  62   // Delete anything in the key before restoring the backup in case someone else
  63   // put new data in the key after Do().
  64   InstallUtil::DeleteRegistryKey(predefined_root_,
  65                                  path_.c_str(),
  66                                  wow64_access_);
  67
  68   // Restore the old contents.  The restoration takes on its default security
  69   // attributes; any custom attributes are lost.
  70   if (!backup_.WriteTo(predefined_root_, path_.c_str(), wow64_access_))
  71     LOG(ERROR) << "Failed to restore key in rollback.";
  72 }