image_properties.h revision 94a4decc032ce0cbe44514436f99cdadbc807436 
1//
2// Copyright (C) 2015 The Android Open Source Project
3//
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at
7//
8//      http://www.apache.org/licenses/LICENSE-2.0
9//
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15//
16
17// This module abstracts the properties tied to the current running image. These
18// properties are meant to be constant during the life of this daemon, but can
19// be modified in dev-move or non-official builds.
20
21#ifndef UPDATE_ENGINE_IMAGE_PROPERTIES_H_
22#define UPDATE_ENGINE_IMAGE_PROPERTIES_H_
23
24#include <string>
25
26namespace chromeos_update_engine {
27
28class SystemState;
29
30// The read-only system properties of the running image.
31struct ImageProperties {
32  // The product id of the image used for all channels, except canary.
33  std::string product_id;
34  // The canary-channel product id.
35  std::string canary_product_id;
36  // The system id for the Android Things SoM, empty for Chrome OS.
37  std::string system_id;
38
39  // The product version of this image.
40  std::string version;
41  // The system version of this image.
42  std::string system_version;
43
44  // A unique string that identifies this build. Normally a combination of the
45  // the version, signing keys and build target.
46  std::string build_fingerprint;
47
48  // The board name this image was built for.
49  std::string board;
50
51  // The release channel this image was obtained from.
52  std::string current_channel;
53
54  // The Omaha URL this image should get updates from.
55  std::string omaha_url;
56};
57
58// The mutable image properties are read-write image properties, initialized
59// with values from the image but can be modified by storing them in the
60// stateful partition.
61struct MutableImageProperties {
62  // The release channel we are tracking.
63  std::string target_channel;
64
65  // Whether powerwash is allowed when downloading an update for the selected
66  // target_channel.
67  bool is_powerwash_allowed{false};
68};
69
70// Loads all the image properties from the running system. In case of error
71// loading any of these properties from the read-only system image a default
72// value may be returned instead.
73ImageProperties LoadImageProperties(SystemState* system_state);
74
75// Loads the mutable image properties from the stateful partition if found or the
76// system image otherwise.
77MutableImageProperties LoadMutableImageProperties(SystemState* system_state);
78
79// Stores the mutable image properties in the stateful partition. Returns
80// whether the operation succeeded.
81bool StoreMutableImageProperties(SystemState* system_state,
82                                 const MutableImageProperties& properties);
83
84// Sets the root_prefix used to load files from during unittests to
85// |test_root_prefix|. Passing a nullptr value resets it to the default.
86namespace test {
87void SetImagePropertiesRootPrefix(const char* test_root_prefix);
88}  // namespace test
89
90}  // namespace chromeos_update_engine
91
92#endif  // UPDATE_ENGINE_IMAGE_PROPERTIES_H_
93