chrome/installer/util/registry_key_backup.h

   1 // Copyright (c) 2011 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 #ifndef CHROME_INSTALLER_UTIL_REGISTRY_KEY_BACKUP_H_
   6 #define CHROME_INSTALLER_UTIL_REGISTRY_KEY_BACKUP_H_
   7
   8 #include <windows.h>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/scoped_ptr.h"
  12
  13 // A container for a registry key, its values, and its subkeys.  We don't use
  14 // more obvious methods for various reasons:
  15 // - RegCopyTree isn't supported pre-Vista, so we'd have to do something
  16 //   different for XP anyway.
  17 // - SHCopyKey can't copy subkeys into a volatile destination, so we'd have to
  18 //   worry about polluting the registry.
  19 // We don't persist security attributes since we only delete keys that we own,
  20 // and we don't set custom attributes on them anyway.
  21 class RegistryKeyBackup {
  22  public:
  23   RegistryKeyBackup();
  24   ~RegistryKeyBackup();
  25
  26   // Recursively reads |key_path| into this instance.  Backing up a non-existent
  27   // key is valid.  Returns true if the backup was successful; false otherwise,
  28   // in which case the state of this instance is not modified.
  29   bool Initialize(HKEY root, const wchar_t* key_path, REGSAM wow64_acccess);
  30
  31   // Writes the contents of this instance into |key|.  The contents of
  32   // |key_path| are not modified If this instance is uninitialized or was
  33   // initialized from a non-existent key.
  34   bool WriteTo(HKEY root, const wchar_t* key_path, REGSAM wow64_acccess) const;
  35
  36   void swap(RegistryKeyBackup& other) {
  37     key_data_.swap(other.key_data_);
  38   }
  39
  40  private:
  41   class KeyData;
  42
  43   // The values and subkeys of the backed-up key.
  44   scoped_ptr<KeyData> key_data_;
  45
  46   DISALLOW_COPY_AND_ASSIGN(RegistryKeyBackup);
  47 };
  48
  49 #endif  // CHROME_INSTALLER_UTIL_REGISTRY_KEY_BACKUP_H_