chrome/installer/setup/update_active_setup_version_work_item.h

   1 // Copyright 2015 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_SETUP_UPDATE_ACTIVE_SETUP_VERSION_WORK_ITEM_H_
   6 #define CHROME_INSTALLER_SETUP_UPDATE_ACTIVE_SETUP_VERSION_WORK_ITEM_H_
   7
   8 #include "base/macros.h"
   9 #include "base/strings/string16.h"
  10 #include "chrome/installer/util/set_reg_value_work_item.h"
  11 #include "chrome/installer/util/work_item.h"
  12
  13 // A WorkItem that updates (or installs if not present) the Active Setup
  14 // "Version" field in the registry. Optionally bumping the OS_UPGRADES component
  15 // on demand. This WorkItem is only viable on machine-wide installs.
  16 class UpdateActiveSetupVersionWorkItem : public WorkItem {
  17  public:
  18   // The components of the Active Setup Version entry, in order.
  19   enum VersionComponent {
  20     // The major version.
  21     MAJOR,
  22     // Unused component, always 0 for now.
  23     UNUSED1,
  24     // Number of OS upgrades handled since original install.
  25     OS_UPGRADES,
  26     // Unused component, always 0 for now.
  27     UNUSED2,
  28   };
  29
  30   // The operation to be performed by this UpdateActiveSetupVersionWorkItem.
  31   enum Operation {
  32     // Update (or install if not present) the Active Setup "Version" in the
  33     // registry.
  34     UPDATE,
  35     // Also bump the OS_UPGRADES component on top of updating the version
  36     // (will default to 1 if the version was absent or invalid).
  37     UPDATE_AND_BUMP_OS_UPGRADES_COMPONENT,
  38   };
  39
  40   // Constructs an UpdateActiveSetupVersionWorkItem that will perform
  41   // |operation| on the |active_setup_path| key in the registry. This key needs
  42   // to exist when this WorkItem is ran.
  43   UpdateActiveSetupVersionWorkItem(const base::string16& active_setup_path,
  44                                    Operation operation);
  45
  46   // Overriden from WorkItem.
  47   bool Do() override;
  48   void Rollback() override;
  49
  50  private:
  51   // Returns the updated Active Setup version to be used based on the
  52   // |existing_version|.
  53   base::string16 GetUpdatedActiveSetupVersion(
  54       const base::string16& existing_version);
  55
  56   // The underlying WorkItem re-used to operate forward and backward on the
  57   // registry.
  58   SetRegValueWorkItem set_reg_value_work_item_;
  59
  60   // The Operation to be performed by this WorkItem when executed.
  61   const Operation operation_;
  62
  63   DISALLOW_COPY_AND_ASSIGN(UpdateActiveSetupVersionWorkItem);
  64 };
  65
  66 #endif  // CHROME_INSTALLER_SETUP_UPDATE_ACTIVE_SETUP_VERSION_WORK_ITEM_H_