delete_reg_value_work_item.h revision 5821806d5e7f356e8fa4b058a389a808ea183019 
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_DELETE_REG_VALUE_WORK_ITEM_H_
6#define CHROME_INSTALLER_UTIL_DELETE_REG_VALUE_WORK_ITEM_H_
7
8#include <windows.h>
9
10#include <string>
11
12#include "chrome/installer/util/work_item.h"
13
14// A WorkItem subclass that deletes a registry value with REG_SZ, REG_DWORD, or
15// REG_QWORD type at the specified path. The value is only deleted if the target
16// key exists.
17class DeleteRegValueWorkItem : public WorkItem {
18 public:
19  virtual ~DeleteRegValueWorkItem();
20
21  virtual bool Do();
22
23  virtual void Rollback();
24
25 private:
26  friend class WorkItem;
27
28  enum DeletionStatus {
29    // The status before Do is called.
30    DELETE_VALUE,
31    // One possible outcome after Do(). Value is deleted.
32    VALUE_DELETED,
33    // One possible outcome after Do(). Value is not found.
34    VALUE_NOT_FOUND,
35    // The status after Do() and Rollback() is called.
36    VALUE_ROLLED_BACK,
37    // Another possible outcome after Do() (when there is an error).
38    VALUE_UNCHANGED
39  };
40
41  DeleteRegValueWorkItem(HKEY predefined_root, const std::wstring& key_path,
42                         const std::wstring& value_name);
43
44  // Root key of the target key under which the value is set. The root key can
45  // only be one of the predefined keys on Windows.
46  HKEY predefined_root_;
47
48  // Path of the target key under which the value is set.
49  std::wstring key_path_;
50
51  // Name of the value to be set.
52  std::wstring value_name_;
53
54  DeletionStatus status_;
55
56  // Previous value.
57  DWORD previous_type_;
58  std::string previous_value_;
59};
60
61#endif  // CHROME_INSTALLER_UTIL_DELETE_REG_VALUE_WORK_ITEM_H_
62