image_properties_android.cc 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#include "update_engine/image_properties.h"
18
19#include <string>
20
21#include <base/logging.h>
22#include <brillo/osrelease_reader.h>
23#include <cutils/properties.h>
24
25#include "update_engine/common/boot_control_interface.h"
26#include "update_engine/common/constants.h"
27#include "update_engine/common/platform_constants.h"
28#include "update_engine/common/prefs_interface.h"
29#include "update_engine/system_state.h"
30
31namespace chromeos_update_engine {
32
33namespace {
34
35// Build time properties name used in Android Things.
36const char kProductId[] = "product_id";
37const char kProductVersion[] = "product_version";
38const char kSystemId[] = "system_id";
39const char kSystemVersion[] = "system_version";
40
41// Prefs used to store the target channel and powerwash settings.
42const char kPrefsImgPropChannelName[] = "img-prop-channel-name";
43const char kPrefsImgPropPowerwashAllowed[] = "img-prop-powerwash-allowed";
44
45// System properties that identifies the "board".
46const char kPropProductName[] = "ro.product.name";
47const char kPropBuildFingerprint[] = "ro.build.fingerprint";
48
49std::string GetStringWithDefault(const brillo::OsReleaseReader& osrelease,
50                                 const std::string& key,
51                                 const std::string& default_value) {
52  std::string result;
53  if (osrelease.GetString(key, &result))
54    return result;
55  LOG(INFO) << "Cannot load ImageProperty " << key << ", using default value "
56            << default_value;
57  return default_value;
58}
59
60}  // namespace
61
62namespace test {
63void SetImagePropertiesRootPrefix(const char* /* test_root_prefix */) {}
64}  // namespace test
65
66ImageProperties LoadImageProperties(SystemState* system_state) {
67  ImageProperties result;
68
69  brillo::OsReleaseReader osrelease;
70  osrelease.Load();
71  result.product_id =
72      GetStringWithDefault(osrelease, kProductId, "invalid-product");
73  result.system_id = GetStringWithDefault(
74      osrelease, kSystemId, "developer-boards:brillo-starter-board");
75  result.canary_product_id = result.product_id;
76  std::string system_version =
77      GetStringWithDefault(osrelease, kSystemVersion, "0.0.0.0");
78  std::string product_version =
79      GetStringWithDefault(osrelease, kProductVersion, "0.0.0.0");
80  result.version = product_version;
81  result.system_version = system_version;
82
83  char prop[PROPERTY_VALUE_MAX];
84  property_get(kPropProductName, prop, "brillo");
85  result.board = prop;
86
87  property_get(kPropBuildFingerprint, prop, "none");
88  result.build_fingerprint = prop;
89
90  // Brillo images don't have a channel assigned. We stored the name of the
91  // channel where we got the image from in prefs at the time of the update, so
92  // we use that as the current channel if available. During provisioning, there
93  // is no value assigned, so we default to the "stable-channel".
94  std::string current_channel_key =
95      kPrefsChannelOnSlotPrefix +
96      std::to_string(system_state->boot_control()->GetCurrentSlot());
97  std::string current_channel;
98  if (!system_state->prefs()->Exists(current_channel_key) ||
99      !system_state->prefs()->GetString(current_channel_key, &current_channel))
100    current_channel = "stable-channel";
101  result.current_channel = current_channel;
102
103  // Brillo only supports the official omaha URL.
104  result.omaha_url = constants::kOmahaDefaultProductionURL;
105
106  return result;
107}
108
109MutableImageProperties LoadMutableImageProperties(SystemState* system_state) {
110  MutableImageProperties result;
111  PrefsInterface* const prefs = system_state->prefs();
112  if (!prefs->GetString(kPrefsImgPropChannelName, &result.target_channel))
113    result.target_channel.clear();
114  if (!prefs->GetBoolean(kPrefsImgPropPowerwashAllowed,
115                         &result.is_powerwash_allowed)) {
116    result.is_powerwash_allowed = false;
117  }
118  return result;
119}
120
121bool StoreMutableImageProperties(SystemState* system_state,
122                                 const MutableImageProperties& properties) {
123  PrefsInterface* const prefs = system_state->prefs();
124  return (
125      prefs->SetString(kPrefsImgPropChannelName, properties.target_channel) &&
126      prefs->SetBoolean(kPrefsImgPropPowerwashAllowed,
127                        properties.is_powerwash_allowed));
128}
129
130}  // namespace chromeos_update_engine
131