chrome/browser/sessions/base_session_service.h

   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 #ifndef CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_
   6 #define CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/callback.h"
  10 #include "base/files/file_path.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/location.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/scoped_vector.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "base/task/cancelable_task_tracker.h"
  17 #include "base/threading/sequenced_worker_pool.h"
  18 #include "chrome/browser/common/cancelable_request.h"
  19 #include "chrome/browser/sessions/session_id.h"
  20 #include "url/gurl.h"
  21
  22 class Profile;
  23 class SessionBackend;
  24 class SessionCommand;
  25
  26 namespace sessions {
  27 class SerializedNavigationEntry;
  28 }
  29
  30 // BaseSessionService is the super class of both tab restore service and
  31 // session service. It contains commonality needed by both, in particular
  32 // it manages a set of SessionCommands that are periodically sent to a
  33 // SessionBackend.
  34 class BaseSessionService : public CancelableRequestProvider {
  35  public:
  36   // Identifies the type of session service this is. This is used by the
  37   // backend to determine the name of the files.
  38   enum SessionType {
  39     SESSION_RESTORE,
  40     TAB_RESTORE
  41   };
  42
  43   // Creates a new BaseSessionService. After creation you need to invoke
  44   // Init.
  45   // |type| gives the type of session service, |profile| the profile and
  46   // |path| the path to save files to. If |profile| is non-NULL, |path| is
  47   // ignored and instead the path comes from the profile.
  48   BaseSessionService(SessionType type,
  49                      Profile* profile,
  50                      const base::FilePath& path);
  51
  52   Profile* profile() const { return profile_; }
  53
  54   // Deletes the last session.
  55   void DeleteLastSession();
  56
  57   typedef base::Callback<void(ScopedVector<SessionCommand>)>
  58       InternalGetCommandsCallback;
  59
  60  protected:
  61   virtual ~BaseSessionService();
  62
  63   // Returns the backend.
  64   SessionBackend* backend() const { return backend_.get(); }
  65
  66   // Returns the set of commands that needed to be scheduled. The commands
  67   // in the vector are owned by BaseSessionService, until they are scheduled
  68   // on the backend at which point the backend owns the commands.
  69   std::vector<SessionCommand*>&  pending_commands() {
  70     return pending_commands_;
  71   }
  72
  73   // Whether the next save resets the file before writing to it.
  74   void set_pending_reset(bool value) { pending_reset_ = value; }
  75   bool pending_reset() const { return pending_reset_; }
  76
  77   // Returns the number of commands sent down since the last reset.
  78   int commands_since_reset() const { return commands_since_reset_; }
  79
  80   // Schedules a command. This adds |command| to pending_commands_ and
  81   // invokes StartSaveTimer to start a timer that invokes Save at a later
  82   // time.
  83   virtual void ScheduleCommand(SessionCommand* command);
  84
  85   // Starts the timer that invokes Save (if timer isn't already running).
  86   void StartSaveTimer();
  87
  88   // Saves pending commands to the backend. This is invoked from the timer
  89   // scheduled by StartSaveTimer.
  90   virtual void Save();
  91
  92   // Creates a SessionCommand that represents a navigation.
  93   SessionCommand* CreateUpdateTabNavigationCommand(
  94       SessionID::id_type command_id,
  95       SessionID::id_type tab_id,
  96       const sessions::SerializedNavigationEntry& navigation);
  97
  98   // Creates a SessionCommand that represents marking a tab as an application.
  99   SessionCommand* CreateSetTabExtensionAppIDCommand(
 100       SessionID::id_type command_id,
 101       SessionID::id_type tab_id,
 102       const std::string& extension_id);
 103
 104   // Creates a SessionCommand that containing user agent override used by a
 105   // tab's navigations.
 106   SessionCommand* CreateSetTabUserAgentOverrideCommand(
 107       SessionID::id_type command_id,
 108       SessionID::id_type tab_id,
 109       const std::string& user_agent_override);
 110
 111   // Creates a SessionCommand stores a browser window's app name.
 112   SessionCommand* CreateSetWindowAppNameCommand(
 113       SessionID::id_type command_id,
 114       SessionID::id_type window_id,
 115       const std::string& app_name);
 116
 117   // Converts a SessionCommand previously created by
 118   // CreateUpdateTabNavigationCommand into a
 119   // sessions::SerializedNavigationEntry. Returns true on success. If
 120   // successful |tab_id| is set to the id of the restored tab.
 121   bool RestoreUpdateTabNavigationCommand(
 122       const SessionCommand& command,
 123       sessions::SerializedNavigationEntry* navigation,
 124       SessionID::id_type* tab_id);
 125
 126   // Extracts a SessionCommand as previously created by
 127   // CreateSetTabExtensionAppIDCommand into the tab id and application
 128   // extension id.
 129   bool RestoreSetTabExtensionAppIDCommand(
 130       const SessionCommand& command,
 131       SessionID::id_type* tab_id,
 132       std::string* extension_app_id);
 133
 134   // Extracts a SessionCommand as previously created by
 135   // CreateSetTabUserAgentOverrideCommand into the tab id and user agent.
 136   bool RestoreSetTabUserAgentOverrideCommand(
 137       const SessionCommand& command,
 138       SessionID::id_type* tab_id,
 139       std::string* user_agent_override);
 140
 141   // Extracts a SessionCommand as previously created by
 142   // CreateSetWindowAppNameCommand into the window id and application name.
 143   bool RestoreSetWindowAppNameCommand(
 144       const SessionCommand& command,
 145       SessionID::id_type* window_id,
 146       std::string* app_name);
 147
 148   // Returns true if the entry at specified |url| should be written to disk.
 149   bool ShouldTrackEntry(const GURL& url);
 150
 151   // Invokes SessionBackend::ReadLastSessionCommands with callback on the
 152   // backend thread.
 153   // If testing, SessionBackend::ReadLastSessionCommands is invoked directly.
 154   base::CancelableTaskTracker::TaskId ScheduleGetLastSessionCommands(
 155       const InternalGetCommandsCallback& callback,
 156       base::CancelableTaskTracker* tracker);
 157
 158   // This posts the task to the SequencedWorkerPool, or run immediately
 159   // if the SequencedWorkerPool has been shutdown.
 160   bool RunTaskOnBackendThread(const tracked_objects::Location& from_here,
 161                               const base::Closure& task);
 162
 163   // Max number of navigation entries in each direction we'll persist.
 164   static const int max_persist_navigation_count;
 165
 166  private:
 167   friend class BetterSessionRestoreCrashTest;
 168
 169   // The profile. This may be null during testing.
 170   Profile* profile_;
 171
 172   // The backend.
 173   scoped_refptr<SessionBackend> backend_;
 174
 175   // Used to invoke Save.
 176   base::WeakPtrFactory<BaseSessionService> weak_factory_;
 177
 178   // Commands we need to send over to the backend.
 179   std::vector<SessionCommand*>  pending_commands_;
 180
 181   // Whether the backend file should be recreated the next time we send
 182   // over the commands.
 183   bool pending_reset_;
 184
 185   // The number of commands sent to the backend before doing a reset.
 186   int commands_since_reset_;
 187
 188   // A token to make sure that all tasks will be serialized.
 189   base::SequencedWorkerPool::SequenceToken sequence_token_;
 190
 191   DISALLOW_COPY_AND_ASSIGN(BaseSessionService);
 192 };
 193
 194 #endif  // CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_