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.
21class 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_
50