version_loader.cc revision dc0f95d653279beabeb9817299e2902918ba123e 
1// Copyright (c) 2010 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#include "chrome/browser/chromeos/version_loader.h"
6
7#include <vector>
8
9#include "base/file_path.h"
10#include "base/file_util.h"
11#include "base/message_loop.h"
12#include "base/string_split.h"
13#include "base/string_util.h"
14#include "base/threading/thread.h"
15#include "base/time.h"
16#include "chrome/browser/browser_process.h"
17#include "content/browser/browser_thread.h"
18
19namespace chromeos {
20
21// File to look for version number in.
22static const char kPath[] = "/etc/lsb-release";
23
24VersionLoader::VersionLoader() : backend_(new Backend()) {
25}
26
27// Beginning of line we look for that gives full version number.
28// Format: x.x.xx.x (Developer|Official build extra info) board info
29// static
30const char VersionLoader::kFullVersionPrefix[] =
31    "CHROMEOS_RELEASE_DESCRIPTION=";
32
33// Same but for short version (x.x.xx.x).
34// static
35const char VersionLoader::kVersionPrefix[] = "CHROMEOS_RELEASE_VERSION=";
36
37VersionLoader::Handle VersionLoader::GetVersion(
38    CancelableRequestConsumerBase* consumer,
39    VersionLoader::GetVersionCallback* callback,
40    VersionFormat format) {
41  if (!g_browser_process->file_thread()) {
42    // This should only happen if Chrome is shutting down, so we don't do
43    // anything.
44    return 0;
45  }
46
47  scoped_refptr<GetVersionRequest> request(new GetVersionRequest(callback));
48  AddRequest(request, consumer);
49
50  g_browser_process->file_thread()->message_loop()->PostTask(
51      FROM_HERE,
52      NewRunnableMethod(backend_.get(), &Backend::GetVersion, request, format));
53  return request->handle();
54}
55
56// static
57std::string VersionLoader::ParseVersion(const std::string& contents,
58                                        const std::string& prefix) {
59  // The file contains lines such as:
60  // XXX=YYY
61  // AAA=ZZZ
62  // Split the lines and look for the one that starts with prefix. The version
63  // file is small, which is why we don't try and be tricky.
64  std::vector<std::string> lines;
65  base::SplitString(contents, '\n', &lines);
66  for (size_t i = 0; i < lines.size(); ++i) {
67    if (StartsWithASCII(lines[i], prefix, false)) {
68      std::string version = lines[i].substr(std::string(prefix).size());
69      if (version.size() > 1 && version[0] == '"' &&
70          version[version.size() - 1] == '"') {
71        // Trim trailing and leading quotes.
72        version = version.substr(1, version.size() - 2);
73      }
74      return version;
75    }
76  }
77  return std::string();
78}
79
80void VersionLoader::Backend::GetVersion(
81    scoped_refptr<GetVersionRequest> request,
82    VersionFormat format) {
83  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
84  if (request->canceled())
85    return;
86
87  std::string version;
88  std::string contents;
89  const FilePath file_path(kPath);
90  if (file_util::ReadFileToString(file_path, &contents)) {
91    version = ParseVersion(
92        contents,
93        (format == VERSION_FULL) ? kFullVersionPrefix : kVersionPrefix);
94  }
95
96  if (format == VERSION_SHORT_WITH_DATE) {
97    base::PlatformFileInfo fileinfo;
98    if (file_util::GetFileInfo(file_path, &fileinfo)) {
99      base::Time::Exploded ctime;
100      fileinfo.creation_time.UTCExplode(&ctime);
101      version += StringPrintf("-%02u.%02u.%02u",
102                              ctime.year % 100,
103                              ctime.month,
104                              ctime.day_of_month);
105    }
106  }
107
108  request->ForwardResult(GetVersionCallback::TupleType(request->handle(),
109                                                       version));
110}
111
112}  // namespace chromeos
113