1//
2// Copyright (C) 2012 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 <sys/stat.h>
18#include <sys/types.h>
19#include <xz.h>
20
21#include <base/at_exit.h>
22#include <base/command_line.h>
23#include <base/logging.h>
24#include <brillo/flag_helper.h>
25
26#include "update_engine/common/daemon_base.h"
27#include "update_engine/common/logging.h"
28#include "update_engine/common/subprocess.h"
29#include "update_engine/common/terminator.h"
30#include "update_engine/common/utils.h"
31
32using std::string;
33
34int main(int argc, char** argv) {
35  DEFINE_bool(logtofile, false, "Write logs to a file in log_dir.");
36  DEFINE_bool(logtostderr,
37              false,
38              "Write logs to stderr instead of to a file in log_dir.");
39  DEFINE_bool(foreground, false, "Don't daemon()ize; run in foreground.");
40
41  chromeos_update_engine::Terminator::Init();
42  brillo::FlagHelper::Init(argc, argv, "A/B Update Engine");
43
44  // We have two logging flags "--logtostderr" and "--logtofile"; and the logic
45  // to choose the logging destination is:
46  // 1. --logtostderr --logtofile -> logs to both
47  // 2. --logtostderr             -> logs to system debug
48  // 3. --logtofile or no flags   -> logs to file
49  bool log_to_system = FLAGS_logtostderr;
50  bool log_to_file = FLAGS_logtofile || !FLAGS_logtostderr;
51  chromeos_update_engine::SetupLogging(log_to_system, log_to_file);
52  if (!FLAGS_foreground)
53    PLOG_IF(FATAL, daemon(0, 0) == 1) << "daemon() failed";
54
55  LOG(INFO) << "A/B Update Engine starting";
56
57  // xz-embedded requires to initialize its CRC-32 table once on startup.
58  xz_crc32_init();
59
60  // Ensure that all written files have safe permissions.
61  // This is a mask, so we _block_ all permissions for the group owner and other
62  // users but allow all permissions for the user owner. We allow execution
63  // for the owner so we can create directories.
64  // Done _after_ log file creation.
65  umask(S_IRWXG | S_IRWXO);
66
67  auto daemon = chromeos_update_engine::DaemonBase::CreateInstance();
68  int exit_code = daemon->Run();
69
70  chromeos_update_engine::Subprocess::Get().FlushBufferedLogsAtExit();
71
72  LOG(INFO) << "A/B Update Engine terminating with exit code " << exit_code;
73  return exit_code;
74}
75