chrome/browser/chromeos/version_loader.h

   1 // Copyright (c) 2011 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 #ifndef CHROME_BROWSER_CHROMEOS_VERSION_LOADER_H_
   6 #define CHROME_BROWSER_CHROMEOS_VERSION_LOADER_H_
   7
   8 #include <string>
   9
  10 #include "base/callback.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/task/cancelable_task_tracker.h"
  13
  14 namespace chromeos {
  15
  16 // ChromeOSVersionLoader loads the version of Chrome OS from the file system.
  17 // Loading is done asynchronously in the blocking thread pool. Once loaded,
  18 // ChromeOSVersionLoader callback to a method of your choice with the version
  19 // (or an empty string if the version couldn't be found).
  20 // To use ChromeOSVersionLoader do the following:
  21 //
  22 // . In your class define a member field of type chromeos::VersionLoader and
  23 //   base::CancelableTaskTracker.
  24 // . Define the callback method, something like:
  25 //   void OnGetChromeOSVersion(const std::string& version);
  26 // . When you want the version invoke:
  27 //   VersionLoader::GetVersion()
  28 //
  29 // This class also provides the ability to load the bios firmware using
  30 //   VersionLoader::GetFirmware()
  31 class VersionLoader {
  32  public:
  33   VersionLoader();
  34   virtual ~VersionLoader();
  35
  36   enum VersionFormat {
  37     VERSION_SHORT,
  38     VERSION_SHORT_WITH_DATE,
  39     VERSION_FULL,
  40   };
  41
  42   // Signature
  43   typedef base::Callback<void(const std::string&)> GetVersionCallback;
  44   typedef base::Callback<void(const std::string&)> GetFirmwareCallback;
  45
  46   // Asynchronously requests the version.
  47   // If |full_version| is true version string with extra info is extracted,
  48   // otherwise it's in short format x.x.xx.x.
  49   base::CancelableTaskTracker::TaskId GetVersion(
  50       VersionFormat format,
  51       const GetVersionCallback& callback,
  52       base::CancelableTaskTracker* tracker);
  53
  54   base::CancelableTaskTracker::TaskId GetFirmware(
  55       const GetFirmwareCallback& callback,
  56       base::CancelableTaskTracker* tracker);
  57
  58  private:
  59   FRIEND_TEST_ALL_PREFIXES(VersionLoaderTest, ParseFirmware);
  60
  61   // VersionLoader calls into the Backend in the blocking thread pool to load
  62   // and extract the version.
  63   class Backend : public base::RefCountedThreadSafe<Backend> {
  64    public:
  65     Backend() {}
  66
  67     // Gets the version number from base::SysInfo. This is invoked on the
  68     // blocking thread pool.
  69     void GetVersion(VersionFormat format, std::string* version);
  70
  71     // Calls ParseFirmware to get the firmware value. This is invoked on the
  72     // blocking thread pool.
  73     void GetFirmware(std::string* firmware);
  74
  75    private:
  76     friend class base::RefCountedThreadSafe<Backend>;
  77
  78     ~Backend() {}
  79
  80     DISALLOW_COPY_AND_ASSIGN(Backend);
  81   };
  82
  83   // Extracts the firmware from the file.
  84   static std::string ParseFirmware(const std::string& contents);
  85
  86   scoped_refptr<Backend> backend_;
  87
  88   DISALLOW_COPY_AND_ASSIGN(VersionLoader);
  89 };
  90
  91 }  // namespace chromeos
  92
  93 #endif  // CHROME_BROWSER_CHROMEOS_VERSION_LOADER_H_