components/sessions/session_service_commands.cc

   1 // Copyright 2014 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 "components/sessions/session_service_commands.h"
   6
   7 #include <vector>
   8
   9 #include "base/pickle.h"
  10 #include "components/sessions/base_session_service_commands.h"
  11 #include "components/sessions/base_session_service_delegate.h"
  12 #include "components/sessions/session_command.h"
  13 #include "components/sessions/session_types.h"
  14
  15 namespace sessions {
  16
  17 // Identifier for commands written to file.
  18 static const SessionCommand::id_type kCommandSetTabWindow = 0;
  19 // OBSOLETE Superseded by kCommandSetWindowBounds3.
  20 // static const SessionCommand::id_type kCommandSetWindowBounds = 1;
  21 static const SessionCommand::id_type kCommandSetTabIndexInWindow = 2;
  22 static const SessionCommand::id_type
  23     kCommandTabNavigationPathPrunedFromBack = 5;
  24 static const SessionCommand::id_type kCommandUpdateTabNavigation = 6;
  25 static const SessionCommand::id_type kCommandSetSelectedNavigationIndex = 7;
  26 static const SessionCommand::id_type kCommandSetSelectedTabInIndex = 8;
  27 static const SessionCommand::id_type kCommandSetWindowType = 9;
  28 // OBSOLETE Superseded by kCommandSetWindowBounds3. Except for data migration.
  29 // static const SessionCommand::id_type kCommandSetWindowBounds2 = 10;
  30 static const SessionCommand::id_type
  31     kCommandTabNavigationPathPrunedFromFront = 11;
  32 static const SessionCommand::id_type kCommandSetPinnedState = 12;
  33 static const SessionCommand::id_type kCommandSetExtensionAppID = 13;
  34 static const SessionCommand::id_type kCommandSetWindowBounds3 = 14;
  35 static const SessionCommand::id_type kCommandSetWindowAppName = 15;
  36 static const SessionCommand::id_type kCommandTabClosed = 16;
  37 static const SessionCommand::id_type kCommandWindowClosed = 17;
  38 static const SessionCommand::id_type kCommandSetTabUserAgentOverride = 18;
  39 static const SessionCommand::id_type kCommandSessionStorageAssociated = 19;
  40 static const SessionCommand::id_type kCommandSetActiveWindow = 20;
  41 static const SessionCommand::id_type kCommandLastActiveTime = 21;
  42
  43 namespace {
  44
  45 // Various payload structures.
  46 struct ClosedPayload {
  47   SessionID::id_type id;
  48   int64 close_time;
  49 };
  50
  51 struct WindowBoundsPayload2 {
  52   SessionID::id_type window_id;
  53   int32 x;
  54   int32 y;
  55   int32 w;
  56   int32 h;
  57   bool is_maximized;
  58 };
  59
  60 struct WindowBoundsPayload3 {
  61   SessionID::id_type window_id;
  62   int32 x;
  63   int32 y;
  64   int32 w;
  65   int32 h;
  66   int32 show_state;
  67 };
  68
  69 typedef SessionID::id_type ActiveWindowPayload;
  70
  71 struct IDAndIndexPayload {
  72   SessionID::id_type id;
  73   int32 index;
  74 };
  75
  76 typedef IDAndIndexPayload TabIndexInWindowPayload;
  77
  78 typedef IDAndIndexPayload TabNavigationPathPrunedFromBackPayload;
  79
  80 typedef IDAndIndexPayload SelectedNavigationIndexPayload;
  81
  82 typedef IDAndIndexPayload SelectedTabInIndexPayload;
  83
  84 typedef IDAndIndexPayload WindowTypePayload;
  85
  86 typedef IDAndIndexPayload TabNavigationPathPrunedFromFrontPayload;
  87
  88 struct PinnedStatePayload {
  89   SessionID::id_type tab_id;
  90   bool pinned_state;
  91 };
  92
  93 struct LastActiveTimePayload {
  94   SessionID::id_type tab_id;
  95   int64 last_active_time;
  96 };
  97
  98 // Persisted versions of ui::WindowShowState that are written to disk and can
  99 // never change.
 100 enum PersistedWindowShowState {
 101   // SHOW_STATE_DEFAULT (0) never persisted.
 102   PERSISTED_SHOW_STATE_NORMAL = 1,
 103   PERSISTED_SHOW_STATE_MINIMIZED = 2,
 104   PERSISTED_SHOW_STATE_MAXIMIZED = 3,
 105   // SHOW_STATE_INACTIVE (4) never persisted.
 106   PERSISTED_SHOW_STATE_FULLSCREEN = 5,
 107   PERSISTED_SHOW_STATE_DETACHED_DEPRECATED = 6,
 108   PERSISTED_SHOW_STATE_DOCKED = 7,
 109   PERSISTED_SHOW_STATE_END = 7
 110 };
 111
 112 typedef std::map<SessionID::id_type, SessionTab*> IdToSessionTab;
 113 typedef std::map<SessionID::id_type, SessionWindow*> IdToSessionWindow;
 114
 115 // Assert to ensure PersistedWindowShowState is updated if ui::WindowShowState
 116 // is changed.
 117 static_assert(ui::SHOW_STATE_END ==
 118                   static_cast<ui::WindowShowState>(PERSISTED_SHOW_STATE_END),
 119               "SHOW_STATE_END must equal PERSISTED_SHOW_STATE_END");
 120
 121 // Returns the show state to store to disk based |state|.
 122 PersistedWindowShowState ShowStateToPersistedShowState(
 123     ui::WindowShowState state) {
 124   switch (state) {
 125     case ui::SHOW_STATE_NORMAL:
 126       return PERSISTED_SHOW_STATE_NORMAL;
 127     case ui::SHOW_STATE_MINIMIZED:
 128       return PERSISTED_SHOW_STATE_MINIMIZED;
 129     case ui::SHOW_STATE_MAXIMIZED:
 130       return PERSISTED_SHOW_STATE_MAXIMIZED;
 131     case ui::SHOW_STATE_FULLSCREEN:
 132       return PERSISTED_SHOW_STATE_FULLSCREEN;
 133     case ui::SHOW_STATE_DOCKED:
 134       return PERSISTED_SHOW_STATE_DOCKED;
 135
 136     case ui::SHOW_STATE_DEFAULT:
 137     case ui::SHOW_STATE_INACTIVE:
 138       return PERSISTED_SHOW_STATE_NORMAL;
 139
 140     case ui::SHOW_STATE_END:
 141       break;
 142   }
 143   NOTREACHED();
 144   return PERSISTED_SHOW_STATE_NORMAL;
 145 }
 146
 147 // Lints show state values when read back from persited disk.
 148 ui::WindowShowState PersistedShowStateToShowState(int state) {
 149   switch (state) {
 150     case PERSISTED_SHOW_STATE_NORMAL:
 151       return ui::SHOW_STATE_NORMAL;
 152     case PERSISTED_SHOW_STATE_MINIMIZED:
 153       return ui::SHOW_STATE_MINIMIZED;
 154     case PERSISTED_SHOW_STATE_MAXIMIZED:
 155       return ui::SHOW_STATE_MAXIMIZED;
 156     case PERSISTED_SHOW_STATE_FULLSCREEN:
 157       return ui::SHOW_STATE_FULLSCREEN;
 158     case PERSISTED_SHOW_STATE_DOCKED:
 159       return ui::SHOW_STATE_DOCKED;
 160     case PERSISTED_SHOW_STATE_DETACHED_DEPRECATED:
 161       return ui::SHOW_STATE_NORMAL;
 162   }
 163   NOTREACHED();
 164   return ui::SHOW_STATE_NORMAL;
 165 }
 166
 167 // Iterates through the vector updating the selected_tab_index of each
 168 // SessionWindow based on the actual tabs that were restored.
 169 void UpdateSelectedTabIndex(std::vector<SessionWindow*>* windows) {
 170   for (std::vector<SessionWindow*>::const_iterator i = windows->begin();
 171        i != windows->end(); ++i) {
 172     // See note in SessionWindow as to why we do this.
 173     int new_index = 0;
 174     for (std::vector<SessionTab*>::const_iterator j = (*i)->tabs.begin();
 175          j != (*i)->tabs.end(); ++j) {
 176       if ((*j)->tab_visual_index == (*i)->selected_tab_index) {
 177         new_index = static_cast<int>(j - (*i)->tabs.begin());
 178         break;
 179       }
 180     }
 181     (*i)->selected_tab_index = new_index;
 182   }
 183 }
 184
 185 // Returns the window in windows with the specified id. If a window does
 186 // not exist, one is created.
 187 SessionWindow* GetWindow(SessionID::id_type window_id,
 188                          IdToSessionWindow* windows) {
 189   std::map<int, SessionWindow*>::iterator i = windows->find(window_id);
 190   if (i == windows->end()) {
 191     SessionWindow* window = new SessionWindow();
 192     window->window_id.set_id(window_id);
 193     (*windows)[window_id] = window;
 194     return window;
 195   }
 196   return i->second;
 197 }
 198
 199 // Returns the tab with the specified id in tabs. If a tab does not exist,
 200 // it is created.
 201 SessionTab* GetTab(SessionID::id_type tab_id, IdToSessionTab* tabs) {
 202   DCHECK(tabs);
 203   std::map<int, SessionTab*>::iterator i = tabs->find(tab_id);
 204   if (i == tabs->end()) {
 205     SessionTab* tab = new SessionTab();
 206     tab->tab_id.set_id(tab_id);
 207     (*tabs)[tab_id] = tab;
 208     return tab;
 209   }
 210   return i->second;
 211 }
 212
 213 // Returns an iterator into navigations pointing to the navigation whose
 214 // index matches |index|. If no navigation index matches |index|, the first
 215 // navigation with an index > |index| is returned.
 216 //
 217 // This assumes the navigations are ordered by index in ascending order.
 218 std::vector<sessions::SerializedNavigationEntry>::iterator
 219   FindClosestNavigationWithIndex(
 220     std::vector<sessions::SerializedNavigationEntry>* navigations,
 221     int index) {
 222   DCHECK(navigations);
 223   for (std::vector<sessions::SerializedNavigationEntry>::iterator
 224            i = navigations->begin(); i != navigations->end(); ++i) {
 225     if (i->index() >= index)
 226       return i;
 227   }
 228   return navigations->end();
 229 }
 230
 231 // Function used in sorting windows. Sorting is done based on window id. As
 232 // window ids increment for each new window, this effectively sorts by creation
 233 // time.
 234 static bool WindowOrderSortFunction(const SessionWindow* w1,
 235                                     const SessionWindow* w2) {
 236   return w1->window_id.id() < w2->window_id.id();
 237 }
 238
 239 // Compares the two tabs based on visual index.
 240 static bool TabVisualIndexSortFunction(const SessionTab* t1,
 241                                        const SessionTab* t2) {
 242   const int delta = t1->tab_visual_index - t2->tab_visual_index;
 243   return delta == 0 ? (t1->tab_id.id() < t2->tab_id.id()) : (delta < 0);
 244 }
 245
 246 // Does the following:
 247 // . Deletes and removes any windows with no tabs. NOTE: constrained windows
 248 //   that have been dragged out are of type browser. As such, this preserves any
 249 //   dragged out constrained windows (aka popups that have been dragged out).
 250 // . Sorts the tabs in windows with valid tabs based on the tabs
 251 //   visual order, and adds the valid windows to windows.
 252 void SortTabsBasedOnVisualOrderAndPrune(
 253     std::map<int, SessionWindow*>* windows,
 254     std::vector<SessionWindow*>* valid_windows) {
 255   std::map<int, SessionWindow*>::iterator i = windows->begin();
 256   while (i != windows->end()) {
 257     SessionWindow* window = i->second;
 258     if (window->tabs.empty() || window->is_constrained) {
 259       delete window;
 260       windows->erase(i++);
 261     } else {
 262       // Valid window; sort the tabs and add it to the list of valid windows.
 263       std::sort(window->tabs.begin(), window->tabs.end(),
 264                 &TabVisualIndexSortFunction);
 265       // Otherwise, add the window such that older windows appear first.
 266       if (valid_windows->empty()) {
 267         valid_windows->push_back(window);
 268       } else {
 269         valid_windows->insert(
 270             std::upper_bound(valid_windows->begin(), valid_windows->end(),
 271                              window, &WindowOrderSortFunction),
 272             window);
 273       }
 274       ++i;
 275     }
 276   }
 277 }
 278
 279 // Adds tabs to their parent window based on the tab's window_id. This
 280 // ignores tabs with no navigations.
 281 void AddTabsToWindows(std::map<int, SessionTab*>* tabs,
 282                       std::map<int, SessionWindow*>* windows) {
 283   DVLOG(1) << "AddTabsToWindws";
 284   DVLOG(1) << "Tabs " << tabs->size() << ", windows " << windows->size();
 285   std::map<int, SessionTab*>::iterator i = tabs->begin();
 286   while (i != tabs->end()) {
 287     SessionTab* tab = i->second;
 288     if (tab->window_id.id() && !tab->navigations.empty()) {
 289       SessionWindow* window = GetWindow(tab->window_id.id(), windows);
 290       window->tabs.push_back(tab);
 291       tabs->erase(i++);
 292
 293       // See note in SessionTab as to why we do this.
 294       std::vector<sessions::SerializedNavigationEntry>::iterator j =
 295           FindClosestNavigationWithIndex(&(tab->navigations),
 296                                          tab->current_navigation_index);
 297       if (j == tab->navigations.end()) {
 298         tab->current_navigation_index =
 299             static_cast<int>(tab->navigations.size() - 1);
 300       } else {
 301         tab->current_navigation_index =
 302             static_cast<int>(j - tab->navigations.begin());
 303       }
 304     } else {
 305       // Never got a set tab index in window, or tabs are empty, nothing
 306       // to do.
 307       ++i;
 308     }
 309   }
 310 }
 311
 312 // Creates tabs and windows from the commands specified in |data|. The created
 313 // tabs and windows are added to |tabs| and |windows| respectively, with the
 314 // id of the active window set in |active_window_id|. It is up to the caller
 315 // to delete the tabs and windows added to |tabs| and |windows|.
 316 //
 317 // This does NOT add any created SessionTabs to SessionWindow.tabs, that is
 318 // done by AddTabsToWindows.
 319 bool CreateTabsAndWindows(const ScopedVector<SessionCommand>& data,
 320                           std::map<int, SessionTab*>* tabs,
 321                           std::map<int, SessionWindow*>* windows,
 322                           SessionID::id_type* active_window_id) {
 323   // If the file is corrupt (command with wrong size, or unknown command), we
 324   // still return true and attempt to restore what we we can.
 325   DVLOG(1) << "CreateTabsAndWindows";
 326
 327   for (std::vector<SessionCommand*>::const_iterator i = data.begin();
 328        i != data.end(); ++i) {
 329     const SessionCommand::id_type kCommandSetWindowBounds2 = 10;
 330     const SessionCommand* command = *i;
 331
 332     DVLOG(1) << "Read command " << (int) command->id();
 333     switch (command->id()) {
 334       case kCommandSetTabWindow: {
 335         SessionID::id_type payload[2];
 336         if (!command->GetPayload(payload, sizeof(payload))) {
 337           DVLOG(1) << "Failed reading command " << command->id();
 338           return true;
 339         }
 340         GetTab(payload[1], tabs)->window_id.set_id(payload[0]);
 341         break;
 342       }
 343
 344       // This is here for forward migration only.  New data is saved with
 345       // |kCommandSetWindowBounds3|.
 346       case kCommandSetWindowBounds2: {
 347         WindowBoundsPayload2 payload;
 348         if (!command->GetPayload(&payload, sizeof(payload))) {
 349           DVLOG(1) << "Failed reading command " << command->id();
 350           return true;
 351         }
 352         GetWindow(payload.window_id, windows)->bounds.SetRect(payload.x,
 353                                                               payload.y,
 354                                                               payload.w,
 355                                                               payload.h);
 356         GetWindow(payload.window_id, windows)->show_state =
 357             payload.is_maximized ?
 358                 ui::SHOW_STATE_MAXIMIZED : ui::SHOW_STATE_NORMAL;
 359         break;
 360       }
 361
 362       case kCommandSetWindowBounds3: {
 363         WindowBoundsPayload3 payload;
 364         if (!command->GetPayload(&payload, sizeof(payload))) {
 365           DVLOG(1) << "Failed reading command " << command->id();
 366           return true;
 367         }
 368         GetWindow(payload.window_id, windows)->bounds.SetRect(payload.x,
 369                                                               payload.y,
 370                                                               payload.w,
 371                                                               payload.h);
 372         GetWindow(payload.window_id, windows)->show_state =
 373             PersistedShowStateToShowState(payload.show_state);
 374         break;
 375       }
 376
 377       case kCommandSetTabIndexInWindow: {
 378         TabIndexInWindowPayload payload;
 379         if (!command->GetPayload(&payload, sizeof(payload))) {
 380           DVLOG(1) << "Failed reading command " << command->id();
 381           return true;
 382         }
 383         GetTab(payload.id, tabs)->tab_visual_index = payload.index;
 384         break;
 385       }
 386
 387       case kCommandTabClosed:
 388       case kCommandWindowClosed: {
 389         ClosedPayload payload;
 390         if (!command->GetPayload(&payload, sizeof(payload))) {
 391           DVLOG(1) << "Failed reading command " << command->id();
 392           return true;
 393         }
 394         if (command->id() == kCommandTabClosed) {
 395           delete GetTab(payload.id, tabs);
 396           tabs->erase(payload.id);
 397         } else {
 398           delete GetWindow(payload.id, windows);
 399           windows->erase(payload.id);
 400         }
 401         break;
 402       }
 403
 404       case kCommandTabNavigationPathPrunedFromBack: {
 405         TabNavigationPathPrunedFromBackPayload payload;
 406         if (!command->GetPayload(&payload, sizeof(payload))) {
 407           DVLOG(1) << "Failed reading command " << command->id();
 408           return true;
 409         }
 410         SessionTab* tab = GetTab(payload.id, tabs);
 411         tab->navigations.erase(
 412             FindClosestNavigationWithIndex(&(tab->navigations), payload.index),
 413             tab->navigations.end());
 414         break;
 415       }
 416
 417       case kCommandTabNavigationPathPrunedFromFront: {
 418         TabNavigationPathPrunedFromFrontPayload payload;
 419         if (!command->GetPayload(&payload, sizeof(payload)) ||
 420             payload.index <= 0) {
 421           DVLOG(1) << "Failed reading command " << command->id();
 422           return true;
 423         }
 424         SessionTab* tab = GetTab(payload.id, tabs);
 425
 426         // Update the selected navigation index.
 427         tab->current_navigation_index =
 428             std::max(-1, tab->current_navigation_index - payload.index);
 429
 430         // And update the index of existing navigations.
 431         for (std::vector<sessions::SerializedNavigationEntry>::iterator
 432                  i = tab->navigations.begin();
 433              i != tab->navigations.end();) {
 434           i->set_index(i->index() - payload.index);
 435           if (i->index() < 0)
 436             i = tab->navigations.erase(i);
 437           else
 438             ++i;
 439         }
 440         break;
 441       }
 442
 443       case kCommandUpdateTabNavigation: {
 444         sessions::SerializedNavigationEntry navigation;
 445         SessionID::id_type tab_id;
 446         if (!RestoreUpdateTabNavigationCommand(*command,
 447                                                &navigation,
 448                                                &tab_id)) {
 449           DVLOG(1) << "Failed reading command " << command->id();
 450           return true;
 451         }
 452         SessionTab* tab = GetTab(tab_id, tabs);
 453         std::vector<sessions::SerializedNavigationEntry>::iterator i =
 454             FindClosestNavigationWithIndex(&(tab->navigations),
 455                                            navigation.index());
 456         if (i != tab->navigations.end() && i->index() == navigation.index())
 457           *i = navigation;
 458         else
 459           tab->navigations.insert(i, navigation);
 460         break;
 461       }
 462
 463       case kCommandSetSelectedNavigationIndex: {
 464         SelectedNavigationIndexPayload payload;
 465         if (!command->GetPayload(&payload, sizeof(payload))) {
 466           DVLOG(1) << "Failed reading command " << command->id();
 467           return true;
 468         }
 469         GetTab(payload.id, tabs)->current_navigation_index = payload.index;
 470         break;
 471       }
 472
 473       case kCommandSetSelectedTabInIndex: {
 474         SelectedTabInIndexPayload payload;
 475         if (!command->GetPayload(&payload, sizeof(payload))) {
 476           DVLOG(1) << "Failed reading command " << command->id();
 477           return true;
 478         }
 479         GetWindow(payload.id, windows)->selected_tab_index = payload.index;
 480         break;
 481       }
 482
 483       case kCommandSetWindowType: {
 484         WindowTypePayload payload;
 485         if (!command->GetPayload(&payload, sizeof(payload))) {
 486           DVLOG(1) << "Failed reading command " << command->id();
 487           return true;
 488         }
 489         GetWindow(payload.id, windows)->is_constrained = false;
 490         GetWindow(payload.id, windows)->type =
 491             static_cast<SessionWindow::WindowType>(payload.index);
 492         break;
 493       }
 494
 495       case kCommandSetPinnedState: {
 496         PinnedStatePayload payload;
 497         if (!command->GetPayload(&payload, sizeof(payload))) {
 498           DVLOG(1) << "Failed reading command " << command->id();
 499           return true;
 500         }
 501         GetTab(payload.tab_id, tabs)->pinned = payload.pinned_state;
 502         break;
 503       }
 504
 505       case kCommandSetWindowAppName: {
 506         SessionID::id_type window_id;
 507         std::string app_name;
 508         if (!RestoreSetWindowAppNameCommand(*command, &window_id, &app_name))
 509           return true;
 510
 511         GetWindow(window_id, windows)->app_name.swap(app_name);
 512         break;
 513       }
 514
 515       case kCommandSetExtensionAppID: {
 516         SessionID::id_type tab_id;
 517         std::string extension_app_id;
 518         if (!RestoreSetTabExtensionAppIDCommand(*command,
 519                                                 &tab_id,
 520                                                 &extension_app_id)) {
 521           DVLOG(1) << "Failed reading command " << command->id();
 522           return true;
 523         }
 524
 525         GetTab(tab_id, tabs)->extension_app_id.swap(extension_app_id);
 526         break;
 527       }
 528
 529       case kCommandSetTabUserAgentOverride: {
 530         SessionID::id_type tab_id;
 531         std::string user_agent_override;
 532         if (!RestoreSetTabUserAgentOverrideCommand(
 533                 *command,
 534                 &tab_id,
 535                 &user_agent_override)) {
 536           return true;
 537         }
 538
 539         GetTab(tab_id, tabs)->user_agent_override.swap(user_agent_override);
 540         break;
 541       }
 542
 543       case kCommandSessionStorageAssociated: {
 544         scoped_ptr<base::Pickle> command_pickle(command->PayloadAsPickle());
 545         SessionID::id_type command_tab_id;
 546         std::string session_storage_persistent_id;
 547         base::PickleIterator iter(*command_pickle.get());
 548         if (!iter.ReadInt(&command_tab_id) ||
 549             !iter.ReadString(&session_storage_persistent_id))
 550           return true;
 551         // Associate the session storage back.
 552         GetTab(command_tab_id, tabs)->session_storage_persistent_id =
 553             session_storage_persistent_id;
 554         break;
 555       }
 556
 557       case kCommandSetActiveWindow: {
 558         ActiveWindowPayload payload;
 559         if (!command->GetPayload(&payload, sizeof(payload))) {
 560           DVLOG(1) << "Failed reading command " << command->id();
 561           return true;
 562         }
 563         *active_window_id = payload;
 564         break;
 565       }
 566
 567       case kCommandLastActiveTime: {
 568         LastActiveTimePayload payload;
 569         if (!command->GetPayload(&payload, sizeof(payload))) {
 570           DVLOG(1) << "Failed reading command " << command->id();
 571           return true;
 572         }
 573         SessionTab* tab = GetTab(payload.tab_id, tabs);
 574         tab->last_active_time =
 575             base::TimeTicks::FromInternalValue(payload.last_active_time);
 576         break;
 577       }
 578
 579       default:
 580         // TODO(skuhne): This might call back into a callback handler to extend
 581         // the command set for specific implementations.
 582         DVLOG(1) << "Failed reading an unknown command " << command->id();
 583         return true;
 584     }
 585   }
 586   return true;
 587 }
 588
 589 }  // namespace
 590
 591 scoped_ptr<SessionCommand> CreateSetSelectedTabInWindowCommand(
 592     const SessionID& window_id,
 593     int index) {
 594   SelectedTabInIndexPayload payload = { 0 };
 595   payload.id = window_id.id();
 596   payload.index = index;
 597   scoped_ptr<SessionCommand> command(
 598       new SessionCommand(kCommandSetSelectedTabInIndex, sizeof(payload)));
 599   memcpy(command->contents(), &payload, sizeof(payload));
 600   return command;
 601 }
 602
 603 scoped_ptr<SessionCommand> CreateSetTabWindowCommand(const SessionID& window_id,
 604                                                      const SessionID& tab_id) {
 605   SessionID::id_type payload[] = { window_id.id(), tab_id.id() };
 606   scoped_ptr<SessionCommand> command(
 607       new SessionCommand(kCommandSetTabWindow, sizeof(payload)));
 608   memcpy(command->contents(), payload, sizeof(payload));
 609   return command;
 610 }
 611
 612 scoped_ptr<SessionCommand> CreateSetWindowBoundsCommand(
 613     const SessionID& window_id,
 614     const gfx::Rect& bounds,
 615     ui::WindowShowState show_state) {
 616   WindowBoundsPayload3 payload = { 0 };
 617   payload.window_id = window_id.id();
 618   payload.x = bounds.x();
 619   payload.y = bounds.y();
 620   payload.w = bounds.width();
 621   payload.h = bounds.height();
 622   payload.show_state = ShowStateToPersistedShowState(show_state);
 623   scoped_ptr<SessionCommand> command(
 624       new SessionCommand(kCommandSetWindowBounds3, sizeof(payload)));
 625   memcpy(command->contents(), &payload, sizeof(payload));
 626   return command;
 627 }
 628
 629 scoped_ptr<SessionCommand> CreateSetTabIndexInWindowCommand(
 630     const SessionID& tab_id,
 631     int new_index) {
 632   TabIndexInWindowPayload payload = { 0 };
 633   payload.id = tab_id.id();
 634   payload.index = new_index;
 635   scoped_ptr<SessionCommand> command(
 636       new SessionCommand(kCommandSetTabIndexInWindow, sizeof(payload)));
 637   memcpy(command->contents(), &payload, sizeof(payload));
 638   return command;
 639 }
 640
 641 scoped_ptr<SessionCommand> CreateTabClosedCommand(
 642     const SessionID::id_type tab_id) {
 643   ClosedPayload payload;
 644   // Because of what appears to be a compiler bug setting payload to {0} doesn't
 645   // set the padding to 0, resulting in Purify reporting an UMR when we write
 646   // the structure to disk. To avoid this we explicitly memset the struct.
 647   memset(&payload, 0, sizeof(payload));
 648   payload.id = tab_id;
 649   payload.close_time = base::Time::Now().ToInternalValue();
 650   scoped_ptr<SessionCommand> command(
 651       new SessionCommand(kCommandTabClosed, sizeof(payload)));
 652   memcpy(command->contents(), &payload, sizeof(payload));
 653   return command;
 654 }
 655
 656 scoped_ptr<SessionCommand> CreateWindowClosedCommand(
 657     const SessionID::id_type window_id) {
 658   ClosedPayload payload;
 659   // See comment in CreateTabClosedCommand as to why we do this.
 660   memset(&payload, 0, sizeof(payload));
 661   payload.id = window_id;
 662   payload.close_time = base::Time::Now().ToInternalValue();
 663   scoped_ptr<SessionCommand> command(
 664       new SessionCommand(kCommandWindowClosed, sizeof(payload)));
 665   memcpy(command->contents(), &payload, sizeof(payload));
 666   return command;
 667 }
 668
 669 scoped_ptr<SessionCommand> CreateSetSelectedNavigationIndexCommand(
 670     const SessionID& tab_id,
 671     int index) {
 672   SelectedNavigationIndexPayload payload = { 0 };
 673   payload.id = tab_id.id();
 674   payload.index = index;
 675   scoped_ptr<SessionCommand> command(
 676       new SessionCommand(kCommandSetSelectedNavigationIndex, sizeof(payload)));
 677   memcpy(command->contents(), &payload, sizeof(payload));
 678   return command;
 679 }
 680
 681 scoped_ptr<SessionCommand> CreateSetWindowTypeCommand(
 682     const SessionID& window_id,
 683     SessionWindow::WindowType type) {
 684   WindowTypePayload payload = { 0 };
 685   payload.id = window_id.id();
 686   payload.index = static_cast<int32>(type);
 687   scoped_ptr<SessionCommand> command(
 688       new SessionCommand( kCommandSetWindowType, sizeof(payload)));
 689   memcpy(command->contents(), &payload, sizeof(payload));
 690   return command;
 691 }
 692
 693 scoped_ptr<SessionCommand> CreatePinnedStateCommand(
 694     const SessionID& tab_id,
 695     bool is_pinned) {
 696   PinnedStatePayload payload = { 0 };
 697   payload.tab_id = tab_id.id();
 698   payload.pinned_state = is_pinned;
 699   scoped_ptr<SessionCommand> command(
 700       new SessionCommand(kCommandSetPinnedState, sizeof(payload)));
 701   memcpy(command->contents(), &payload, sizeof(payload));
 702   return command;
 703 }
 704
 705 scoped_ptr<SessionCommand> CreateSessionStorageAssociatedCommand(
 706     const SessionID& tab_id,
 707     const std::string& session_storage_persistent_id) {
 708   base::Pickle pickle;
 709   pickle.WriteInt(tab_id.id());
 710   pickle.WriteString(session_storage_persistent_id);
 711   return scoped_ptr<SessionCommand>(
 712       new SessionCommand(kCommandSessionStorageAssociated, pickle));
 713 }
 714
 715 scoped_ptr<SessionCommand> CreateSetActiveWindowCommand(
 716     const SessionID& window_id) {
 717   ActiveWindowPayload payload = 0;
 718   payload = window_id.id();
 719   scoped_ptr<SessionCommand> command(
 720       new SessionCommand(kCommandSetActiveWindow, sizeof(payload)));
 721   memcpy(command->contents(), &payload, sizeof(payload));
 722   return command;
 723 }
 724
 725 scoped_ptr<SessionCommand> CreateLastActiveTimeCommand(
 726     const SessionID& tab_id,
 727     base::TimeTicks last_active_time) {
 728   LastActiveTimePayload payload = {0};
 729   payload.tab_id = tab_id.id();
 730   payload.last_active_time = last_active_time.ToInternalValue();
 731   scoped_ptr<SessionCommand> command(
 732       new SessionCommand(kCommandLastActiveTime, sizeof(payload)));
 733   memcpy(command->contents(), &payload, sizeof(payload));
 734   return command;
 735 }
 736
 737 scoped_ptr<SessionCommand> CreateTabNavigationPathPrunedFromBackCommand(
 738     const SessionID& tab_id,
 739     int count) {
 740   TabNavigationPathPrunedFromBackPayload payload = { 0 };
 741   payload.id = tab_id.id();
 742   payload.index = count;
 743   scoped_ptr<SessionCommand> command(
 744       new SessionCommand(kCommandTabNavigationPathPrunedFromBack,
 745                          sizeof(payload)));
 746   memcpy(command->contents(), &payload, sizeof(payload));
 747   return command;
 748 }
 749
 750 scoped_ptr<SessionCommand> CreateTabNavigationPathPrunedFromFrontCommand(
 751     const SessionID& tab_id,
 752     int count) {
 753   TabNavigationPathPrunedFromFrontPayload payload = { 0 };
 754   payload.id = tab_id.id();
 755   payload.index = count;
 756   scoped_ptr<SessionCommand> command(
 757       new SessionCommand(kCommandTabNavigationPathPrunedFromFront,
 758                          sizeof(payload)));
 759   memcpy(command->contents(), &payload, sizeof(payload));
 760   return command;
 761 }
 762
 763 scoped_ptr<SessionCommand> CreateUpdateTabNavigationCommand(
 764     const SessionID& tab_id,
 765     const sessions::SerializedNavigationEntry& navigation) {
 766   return CreateUpdateTabNavigationCommand(kCommandUpdateTabNavigation,
 767                                             tab_id.id(),
 768                                             navigation);
 769 }
 770
 771 scoped_ptr<SessionCommand> CreateSetTabExtensionAppIDCommand(
 772     const SessionID& tab_id,
 773     const std::string& extension_id) {
 774   return CreateSetTabExtensionAppIDCommand(kCommandSetExtensionAppID,
 775                                              tab_id.id(),
 776                                              extension_id);
 777 }
 778
 779 scoped_ptr<SessionCommand> CreateSetTabUserAgentOverrideCommand(
 780     const SessionID& tab_id,
 781     const std::string& user_agent_override) {
 782   return CreateSetTabUserAgentOverrideCommand(kCommandSetTabUserAgentOverride,
 783                                                 tab_id.id(),
 784                                                 user_agent_override);
 785 }
 786
 787 scoped_ptr<SessionCommand> CreateSetWindowAppNameCommand(
 788     const SessionID& window_id,
 789     const std::string& app_name) {
 790   return CreateSetWindowAppNameCommand(kCommandSetWindowAppName,
 791                                          window_id.id(),
 792                                          app_name);
 793 }
 794
 795 bool ReplacePendingCommand(BaseSessionService* base_session_service,
 796                            scoped_ptr<SessionCommand>* command) {
 797   // We optimize page navigations, which can happen quite frequently and
 798   // is expensive. And activation is like Highlander, there can only be one!
 799   if ((*command)->id() != kCommandUpdateTabNavigation &&
 800       (*command)->id() != kCommandSetActiveWindow) {
 801     return false;
 802   }
 803   for (ScopedVector<SessionCommand>::const_reverse_iterator i =
 804            base_session_service->pending_commands().rbegin();
 805        i != base_session_service->pending_commands().rend(); ++i) {
 806     SessionCommand* existing_command = *i;
 807     if ((*command)->id() == kCommandUpdateTabNavigation &&
 808         existing_command->id() == kCommandUpdateTabNavigation) {
 809       scoped_ptr<base::Pickle> command_pickle((*command)->PayloadAsPickle());
 810       base::PickleIterator iterator(*command_pickle);
 811       SessionID::id_type command_tab_id;
 812       int command_nav_index;
 813       if (!iterator.ReadInt(&command_tab_id) ||
 814           !iterator.ReadInt(&command_nav_index)) {
 815         return false;
 816       }
 817       SessionID::id_type existing_tab_id;
 818       int existing_nav_index;
 819       {
 820         // Creating a pickle like this means the Pickle references the data from
 821         // the command. Make sure we delete the pickle before the command, else
 822         // the pickle references deleted memory.
 823         scoped_ptr<base::Pickle> existing_pickle(
 824             existing_command->PayloadAsPickle());
 825         iterator = base::PickleIterator(*existing_pickle);
 826         if (!iterator.ReadInt(&existing_tab_id) ||
 827             !iterator.ReadInt(&existing_nav_index)) {
 828           return false;
 829         }
 830       }
 831       if (existing_tab_id == command_tab_id &&
 832           existing_nav_index == command_nav_index) {
 833         // existing_command is an update for the same tab/index pair. Replace
 834         // it with the new one. We need to add to the end of the list just in
 835         // case there is a prune command after the update command.
 836         base_session_service->EraseCommand(*(i.base() - 1));
 837         base_session_service->AppendRebuildCommand((*command).Pass());
 838         return true;
 839       }
 840       return false;
 841     }
 842     if ((*command)->id() == kCommandSetActiveWindow &&
 843         existing_command->id() == kCommandSetActiveWindow) {
 844       base_session_service->SwapCommand(existing_command, (*command).Pass());
 845       return true;
 846     }
 847   }
 848   return false;
 849 }
 850
 851 bool IsClosingCommand(SessionCommand* command) {
 852   return command->id() == kCommandTabClosed ||
 853          command->id() == kCommandWindowClosed;
 854 }
 855
 856 void RestoreSessionFromCommands(const ScopedVector<SessionCommand>& commands,
 857                                 std::vector<SessionWindow*>* valid_windows,
 858                                 SessionID::id_type* active_window_id) {
 859   std::map<int, SessionTab*> tabs;
 860   std::map<int, SessionWindow*> windows;
 861
 862   DVLOG(1) << "RestoreSessionFromCommands " << commands.size();
 863   if (CreateTabsAndWindows(commands, &tabs, &windows, active_window_id)) {
 864     AddTabsToWindows(&tabs, &windows);
 865     SortTabsBasedOnVisualOrderAndPrune(&windows, valid_windows);
 866     UpdateSelectedTabIndex(valid_windows);
 867   }
 868   STLDeleteValues(&tabs);
 869   // Don't delete contents of windows, that is done by the caller as all
 870   // valid windows are added to valid_windows.
 871 }
 872
 873 }  // namespace sessions