chrome/browser/profile_resetter/automatic_profile_resetter_mementos.h

   1 // Copyright 2013 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 // The classes in this file are alternative implementations of the concept of a
   6 // "prompt memento", a token of some kind that gets stored when we show the
   7 // one-time profile reset prompt, and which then serves as a reminder that we
   8 // should not show the prompt again.
   9 //
  10 // In an ideal world, a single implementation would suffice, however, we expect
  11 // that third party software might accidentally interfere with some of these
  12 // methods. We need this redundancy because we want to make absolutely sure that
  13 // we do not annoy the user with the prompt multiple times.
  14
  15 #ifndef CHROME_BROWSER_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_MEMENTOS_H_
  16 #define CHROME_BROWSER_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_MEMENTOS_H_
  17
  18 #include <string>
  19
  20 #include "base/basictypes.h"
  21 #include "base/callback.h"
  22
  23 namespace base {
  24 class FilePath;
  25 }
  26
  27 class Profile;
  28
  29 // This class is a wrapper around the user preference that gets stored when we
  30 // show the one-time profile reset prompt, and which is kept as a reminder that
  31 // we should not show the prompt again.
  32 class PreferenceHostedPromptMemento {
  33  public:
  34   explicit PreferenceHostedPromptMemento(Profile* profile);
  35   ~PreferenceHostedPromptMemento();
  36
  37   std::string ReadValue() const;
  38   void StoreValue(const std::string& value);
  39
  40  private:
  41   Profile* profile_;
  42
  43   DISALLOW_COPY_AND_ASSIGN(PreferenceHostedPromptMemento);
  44 };
  45
  46 // This class is a wrapper around the Local State preference that gets stored
  47 // when we show the one-time profile reset prompt, and which is kept as a
  48 // reminder that we should not show the prompt again.
  49 class LocalStateHostedPromptMemento {
  50  public:
  51   explicit LocalStateHostedPromptMemento(Profile* profile);
  52   ~LocalStateHostedPromptMemento();
  53
  54   std::string ReadValue() const;
  55   void StoreValue(const std::string& value);
  56
  57  private:
  58   // Returns the key that shall be used in the dictionary preference in Local
  59   // State to uniquely identify this profile.
  60   std::string GetProfileKey() const;
  61
  62   Profile* profile_;
  63
  64   DISALLOW_COPY_AND_ASSIGN(LocalStateHostedPromptMemento);
  65 };
  66
  67 // This class manages a marker file that gets stored when we show the one-time
  68 // profile reset prompt, and which is kept as a reminder that we should not show
  69 // the prompt again.
  70 class FileHostedPromptMemento {
  71  public:
  72   typedef base::Callback<void(const std::string&)> ReadValueCallback;
  73
  74   explicit FileHostedPromptMemento(Profile* profile);
  75   ~FileHostedPromptMemento();
  76
  77   // Posts to the FILE thread to read the value, then returns the value to the
  78   // calling thread. It is safe to destroy this object as soon as this method
  79   // (synchronously) returns.
  80   void ReadValue(const ReadValueCallback& callback) const;
  81
  82   // Asynchronously stores the value on the FILE thread. However, it is safe to
  83   // destroy this object as soon as this method (synchronously) returns.
  84   void StoreValue(const std::string& value);
  85
  86  private:
  87   static std::string ReadValueOnFileThread(
  88       const base::FilePath& memento_file_path);
  89   static void StoreValueOnFileThread(const base::FilePath& memento_file_path,
  90                                      const std::string& value);
  91
  92   // Returns the path to the file that shall be used to store this kind of
  93   // memento for this profile.
  94   base::FilePath GetMementoFilePath() const;
  95
  96   Profile* profile_;
  97
  98   DISALLOW_COPY_AND_ASSIGN(FileHostedPromptMemento);
  99 };
 100
 101 #endif  // CHROME_BROWSER_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_MEMENTOS_H_