base/sys_info_chromeos.cc

   1 // Copyright (c) 2012 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 "base/sys_info.h"
   6
   7 #include "base/basictypes.h"
   8 #include "base/file_util.h"
   9 #include "base/files/file_path.h"
  10 #include "base/lazy_instance.h"
  11 #include "base/strings/string_number_conversions.h"
  12 #include "base/strings/string_piece.h"
  13 #include "base/strings/string_tokenizer.h"
  14 #include "base/threading/thread_restrictions.h"
  15
  16 namespace base {
  17
  18 static const char* kLinuxStandardBaseVersionKeys[] = {
  19   "CHROMEOS_RELEASE_VERSION",
  20   "GOOGLE_RELEASE",
  21   "DISTRIB_RELEASE",
  22   NULL
  23 };
  24
  25 const char kLinuxStandardBaseReleaseFile[] = "/etc/lsb-release";
  26
  27 struct ChromeOSVersionNumbers {
  28   ChromeOSVersionNumbers()
  29       : major_version(0),
  30         minor_version(0),
  31         bugfix_version(0),
  32         parsed(false) {
  33   }
  34
  35   int32 major_version;
  36   int32 minor_version;
  37   int32 bugfix_version;
  38   bool parsed;
  39 };
  40
  41 static LazyInstance<ChromeOSVersionNumbers>
  42     g_chrome_os_version_numbers = LAZY_INSTANCE_INITIALIZER;
  43
  44 // static
  45 void SysInfo::OperatingSystemVersionNumbers(int32* major_version,
  46                                             int32* minor_version,
  47                                             int32* bugfix_version) {
  48   if (!g_chrome_os_version_numbers.Get().parsed) {
  49     // The other implementations of SysInfo don't block on the disk.
  50     // See http://code.google.com/p/chromium/issues/detail?id=60394
  51     // Perhaps the caller ought to cache this?
  52     // Temporary allowing while we work the bug out.
  53     ThreadRestrictions::ScopedAllowIO allow_io;
  54
  55     FilePath path(kLinuxStandardBaseReleaseFile);
  56     std::string contents;
  57     if (file_util::ReadFileToString(path, &contents)) {
  58       g_chrome_os_version_numbers.Get().parsed = true;
  59       ParseLsbRelease(contents,
  60           &(g_chrome_os_version_numbers.Get().major_version),
  61           &(g_chrome_os_version_numbers.Get().minor_version),
  62           &(g_chrome_os_version_numbers.Get().bugfix_version));
  63     }
  64   }
  65   *major_version = g_chrome_os_version_numbers.Get().major_version;
  66   *minor_version = g_chrome_os_version_numbers.Get().minor_version;
  67   *bugfix_version = g_chrome_os_version_numbers.Get().bugfix_version;
  68 }
  69
  70 // static
  71 std::string SysInfo::GetLinuxStandardBaseVersionKey() {
  72   return std::string(kLinuxStandardBaseVersionKeys[0]);
  73 }
  74
  75 // static
  76 void SysInfo::ParseLsbRelease(const std::string& lsb_release,
  77                               int32* major_version,
  78                               int32* minor_version,
  79                               int32* bugfix_version) {
  80   size_t version_key_index = std::string::npos;
  81   for (int i = 0; kLinuxStandardBaseVersionKeys[i] != NULL; ++i) {
  82     version_key_index = lsb_release.find(kLinuxStandardBaseVersionKeys[i]);
  83     if (std::string::npos != version_key_index) {
  84       break;
  85     }
  86   }
  87   if (std::string::npos == version_key_index) {
  88     return;
  89   }
  90
  91   size_t start_index = lsb_release.find_first_of('=', version_key_index);
  92   start_index++;  // Move past '='.
  93   size_t length = lsb_release.find_first_of('\n', start_index) - start_index;
  94   std::string version = lsb_release.substr(start_index, length);
  95   StringTokenizer tokenizer(version, ".");
  96   for (int i = 0; i < 3 && tokenizer.GetNext(); ++i) {
  97     if (0 == i) {
  98       StringToInt(StringPiece(tokenizer.token_begin(),
  99                               tokenizer.token_end()),
 100                   major_version);
 101       *minor_version = *bugfix_version = 0;
 102     } else if (1 == i) {
 103       StringToInt(StringPiece(tokenizer.token_begin(),
 104                               tokenizer.token_end()),
 105                   minor_version);
 106     } else {  // 2 == i
 107       StringToInt(StringPiece(tokenizer.token_begin(),
 108                               tokenizer.token_end()),
 109                   bugfix_version);
 110     }
 111   }
 112 }
 113
 114 // static
 115 FilePath SysInfo::GetLsbReleaseFilePath() {
 116   return FilePath(kLinuxStandardBaseReleaseFile);
 117 }
 118
 119 }  // namespace base