components/component_updater/component_updater_service.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/component_updater/component_updater_service.h"
   6
   7 #include <algorithm>
   8 #include <set>
   9 #include <vector>
  10
  11 #include "base/at_exit.h"
  12 #include "base/bind.h"
  13 #include "base/bind_helpers.h"
  14 #include "base/callback.h"
  15 #include "base/compiler_specific.h"
  16 #include "base/files/file_path.h"
  17 #include "base/files/file_util.h"
  18 #include "base/logging.h"
  19 #include "base/macros.h"
  20 #include "base/memory/scoped_ptr.h"
  21 #include "base/message_loop/message_loop_proxy.h"
  22 #include "base/observer_list.h"
  23 #include "base/sequenced_task_runner.h"
  24 #include "base/stl_util.h"
  25 #include "base/threading/sequenced_worker_pool.h"
  26 #include "base/threading/thread_checker.h"
  27 #include "base/timer/timer.h"
  28 #include "components/component_updater/component_patcher_operation.h"
  29 #include "components/component_updater/component_unpacker.h"
  30 #include "components/component_updater/component_updater_configurator.h"
  31 #include "components/component_updater/component_updater_ping_manager.h"
  32 #include "components/component_updater/component_updater_utils.h"
  33 #include "components/component_updater/crx_downloader.h"
  34 #include "components/component_updater/crx_update_item.h"
  35 #include "components/component_updater/update_checker.h"
  36 #include "components/component_updater/update_response.h"
  37 #include "url/gurl.h"
  38
  39 namespace component_updater {
  40
  41 // The component updater is designed to live until process shutdown, so
  42 // base::Bind() calls are not refcounted.
  43
  44 namespace {
  45
  46 // Returns true if the |proposed| version is newer than |current| version.
  47 bool IsVersionNewer(const Version& current, const std::string& proposed) {
  48   Version proposed_ver(proposed);
  49   return proposed_ver.IsValid() && current.CompareTo(proposed_ver) < 0;
  50 }
  51
  52 // Returns true if a differential update is available, it has not failed yet,
  53 // and the configuration allows it.
  54 bool CanTryDiffUpdate(const CrxUpdateItem* update_item,
  55                       const Configurator& config) {
  56   return HasDiffUpdate(update_item) && !update_item->diff_update_failed &&
  57          config.DeltasEnabled();
  58 }
  59
  60 void AppendDownloadMetrics(
  61     const std::vector<CrxDownloader::DownloadMetrics>& source,
  62     std::vector<CrxDownloader::DownloadMetrics>* destination) {
  63   destination->insert(destination->end(), source.begin(), source.end());
  64 }
  65
  66 }  // namespace
  67
  68 CrxUpdateItem::CrxUpdateItem()
  69     : status(kNew),
  70       on_demand(false),
  71       diff_update_failed(false),
  72       error_category(0),
  73       error_code(0),
  74       extra_code1(0),
  75       diff_error_category(0),
  76       diff_error_code(0),
  77       diff_extra_code1(0) {
  78 }
  79
  80 CrxUpdateItem::~CrxUpdateItem() {
  81 }
  82
  83 CrxComponent::CrxComponent()
  84     : installer(NULL), allow_background_download(true) {
  85 }
  86
  87 CrxComponent::~CrxComponent() {
  88 }
  89
  90 //////////////////////////////////////////////////////////////////////////////
  91 // The one and only implementation of the ComponentUpdateService interface. In
  92 // charge of running the show. The main method is ProcessPendingItems() which
  93 // is called periodically to do the upgrades/installs or the update checks.
  94 // An important consideration here is to be as "low impact" as we can to the
  95 // rest of the browser, so even if we have many components registered and
  96 // eligible for update, we only do one thing at a time with pauses in between
  97 // the tasks. Also when we do network requests there is only one |url_fetcher_|
  98 // in flight at a time.
  99 // There are no locks in this code, the main structure |work_items_| is mutated
 100 // only from the main thread. The unpack and installation is done in a blocking
 101 // pool thread. The network requests are done in the IO thread or in the file
 102 // thread.
 103 class CrxUpdateService : public ComponentUpdateService, public OnDemandUpdater {
 104  public:
 105   explicit CrxUpdateService(Configurator* config);
 106   ~CrxUpdateService() override;
 107
 108   // Overrides for ComponentUpdateService.
 109   void AddObserver(Observer* observer) override;
 110   void RemoveObserver(Observer* observer) override;
 111   Status Start() override;
 112   Status Stop() override;
 113   Status RegisterComponent(const CrxComponent& component) override;
 114   std::vector<std::string> GetComponentIDs() const override;
 115   OnDemandUpdater& GetOnDemandUpdater() override;
 116   void MaybeThrottle(const std::string& crx_id,
 117                      const base::Closure& callback) override;
 118   scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner() override;
 119
 120   // Context for a crx download url request.
 121   struct CRXContext {
 122     ComponentInstaller* installer;
 123     std::vector<uint8_t> pk_hash;
 124     std::string id;
 125     std::string fingerprint;
 126     CRXContext() : installer(NULL) {}
 127   };
 128
 129  private:
 130   enum ErrorCategory {
 131     kErrorNone = 0,
 132     kNetworkError,
 133     kUnpackError,
 134     kInstallError,
 135   };
 136
 137   enum StepDelayInterval {
 138     kStepDelayShort = 0,
 139     kStepDelayMedium,
 140     kStepDelayLong,
 141   };
 142
 143   // Overrides for ComponentUpdateService.
 144   bool GetComponentDetails(const std::string& component_id,
 145                            CrxUpdateItem* item) const override;
 146
 147   // Overrides for OnDemandUpdater.
 148   Status OnDemandUpdate(const std::string& component_id) override;
 149
 150   void UpdateCheckComplete(const GURL& original_url,
 151                            int error,
 152                            const std::string& error_message,
 153                            const UpdateResponse::Results& results);
 154   void OnUpdateCheckSucceeded(const UpdateResponse::Results& results);
 155   void OnUpdateCheckFailed(int error, const std::string& error_message);
 156
 157   void DownloadProgress(const std::string& component_id,
 158                         const CrxDownloader::Result& download_result);
 159
 160   void DownloadComplete(scoped_ptr<CRXContext> crx_context,
 161                         const CrxDownloader::Result& download_result);
 162
 163   Status OnDemandUpdateInternal(CrxUpdateItem* item);
 164   Status OnDemandUpdateWithCooldown(CrxUpdateItem* item);
 165
 166   void ProcessPendingItems();
 167
 168   // Find a component that is ready to update.
 169   CrxUpdateItem* FindReadyComponent() const;
 170
 171   // Prepares the components for an update check and initiates the request.
 172   // Returns true if an update check request has been made. Returns false if
 173   // no update check was needed or an error occured.
 174   bool CheckForUpdates();
 175
 176   void UpdateComponent(CrxUpdateItem* workitem);
 177
 178   void ScheduleNextRun(StepDelayInterval step_delay);
 179
 180   void ParseResponse(const std::string& xml);
 181
 182   void Install(scoped_ptr<CRXContext> context, const base::FilePath& crx_path);
 183
 184   void EndUnpacking(const std::string& component_id,
 185                     const base::FilePath& crx_path,
 186                     ComponentUnpacker::Error error,
 187                     int extended_error);
 188
 189   void DoneInstalling(const std::string& component_id,
 190                       ComponentUnpacker::Error error,
 191                       int extended_error);
 192
 193   void ChangeItemState(CrxUpdateItem* item, CrxUpdateItem::Status to);
 194
 195   size_t ChangeItemStatus(CrxUpdateItem::Status from, CrxUpdateItem::Status to);
 196
 197   CrxUpdateItem* FindUpdateItemById(const std::string& id) const;
 198
 199   void NotifyObservers(Observer::Events event, const std::string& id);
 200
 201   bool HasOnDemandItems() const;
 202
 203   Status GetServiceStatus(const CrxUpdateItem::Status status);
 204
 205   scoped_ptr<Configurator> config_;
 206
 207   scoped_ptr<UpdateChecker> update_checker_;
 208
 209   scoped_ptr<PingManager> ping_manager_;
 210
 211   scoped_refptr<ComponentUnpacker> unpacker_;
 212
 213   scoped_ptr<CrxDownloader> crx_downloader_;
 214
 215   // A collection of every work item.
 216   typedef std::vector<CrxUpdateItem*> UpdateItems;
 217   UpdateItems work_items_;
 218
 219   base::OneShotTimer<CrxUpdateService> timer_;
 220
 221   base::ThreadChecker thread_checker_;
 222
 223   // Used to post responses back to the main thread.
 224   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
 225
 226   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
 227
 228   bool running_;
 229
 230   ObserverList<Observer> observer_list_;
 231
 232   DISALLOW_COPY_AND_ASSIGN(CrxUpdateService);
 233 };
 234
 235 //////////////////////////////////////////////////////////////////////////////
 236
 237 CrxUpdateService::CrxUpdateService(Configurator* config)
 238     : config_(config),
 239       ping_manager_(new PingManager(*config)),
 240       main_task_runner_(base::MessageLoopProxy::current()),
 241       blocking_task_runner_(config->GetSequencedTaskRunner()),
 242       running_(false) {
 243 }
 244
 245 CrxUpdateService::~CrxUpdateService() {
 246   // Because we are a singleton, at this point only the main thread should be
 247   // alive, this simplifies the management of the work that could be in
 248   // flight in other threads.
 249   Stop();
 250   STLDeleteElements(&work_items_);
 251 }
 252
 253 void CrxUpdateService::AddObserver(Observer* observer) {
 254   DCHECK(thread_checker_.CalledOnValidThread());
 255   observer_list_.AddObserver(observer);
 256 }
 257
 258 void CrxUpdateService::RemoveObserver(Observer* observer) {
 259   DCHECK(thread_checker_.CalledOnValidThread());
 260   observer_list_.RemoveObserver(observer);
 261 }
 262
 263 ComponentUpdateService::Status CrxUpdateService::Start() {
 264   // Note that RegisterComponent will call Start() when the first
 265   // component is registered, so it can be called twice. This way
 266   // we avoid scheduling the timer if there is no work to do.
 267   VLOG(1) << "CrxUpdateService starting up";
 268   running_ = true;
 269   if (work_items_.empty())
 270     return kOk;
 271
 272   NotifyObservers(Observer::COMPONENT_UPDATER_STARTED, "");
 273
 274   VLOG(1) << "First update attempt will take place in "
 275           << config_->InitialDelay() << " seconds";
 276   timer_.Start(FROM_HERE,
 277                base::TimeDelta::FromSeconds(config_->InitialDelay()),
 278                this,
 279                &CrxUpdateService::ProcessPendingItems);
 280   return kOk;
 281 }
 282
 283 // Stop the main check + update loop. In flight operations will be
 284 // completed.
 285 ComponentUpdateService::Status CrxUpdateService::Stop() {
 286   VLOG(1) << "CrxUpdateService stopping";
 287   running_ = false;
 288   timer_.Stop();
 289   return kOk;
 290 }
 291
 292 bool CrxUpdateService::HasOnDemandItems() const {
 293   class Helper {
 294    public:
 295     static bool IsOnDemand(CrxUpdateItem* item) { return item->on_demand; }
 296   };
 297   return std::find_if(work_items_.begin(),
 298                       work_items_.end(),
 299                       Helper::IsOnDemand) != work_items_.end();
 300 }
 301
 302 // This function sets the timer which will call ProcessPendingItems() or
 303 // ProcessRequestedItem() if there is an on_demand item.  There
 304 // are three kinds of waits:
 305 //  - a short delay, when there is immediate work to be done.
 306 //  - a medium delay, when there are updates to be applied within the current
 307 //    update cycle, or there are components that are still unchecked.
 308 //  - a long delay when a full check/update cycle has completed for all
 309 //    components.
 310 void CrxUpdateService::ScheduleNextRun(StepDelayInterval step_delay) {
 311   DCHECK(thread_checker_.CalledOnValidThread());
 312   DCHECK(!update_checker_);
 313   CHECK(!timer_.IsRunning());
 314   // It could be the case that Stop() had been called while a url request
 315   // or unpacking was in flight, if so we arrive here but |running_| is
 316   // false. In that case do not loop again.
 317   if (!running_)
 318     return;
 319
 320   // Keep the delay short if in the middle of an update (step_delay),
 321   // or there are new requested_work_items_ that have not been processed yet.
 322   int64_t delay_seconds = 0;
 323   if (!HasOnDemandItems()) {
 324     switch (step_delay) {
 325       case kStepDelayShort:
 326         delay_seconds = config_->StepDelay();
 327         break;
 328       case kStepDelayMedium:
 329         delay_seconds = config_->StepDelayMedium();
 330         break;
 331       case kStepDelayLong:
 332         delay_seconds = config_->NextCheckDelay();
 333         break;
 334     }
 335   } else {
 336     delay_seconds = config_->StepDelay();
 337   }
 338
 339   if (step_delay != kStepDelayShort) {
 340     NotifyObservers(Observer::COMPONENT_UPDATER_SLEEPING, "");
 341
 342     // Zero is only used for unit tests.
 343     if (0 == delay_seconds)
 344       return;
 345   }
 346
 347   VLOG(1) << "Scheduling next run to occur in " << delay_seconds << " seconds";
 348   timer_.Start(FROM_HERE,
 349                base::TimeDelta::FromSeconds(delay_seconds),
 350                this,
 351                &CrxUpdateService::ProcessPendingItems);
 352 }
 353
 354 // Given a extension-like component id, find the associated component.
 355 CrxUpdateItem* CrxUpdateService::FindUpdateItemById(
 356     const std::string& id) const {
 357   DCHECK(thread_checker_.CalledOnValidThread());
 358   CrxUpdateItem::FindById finder(id);
 359   UpdateItems::const_iterator it =
 360       std::find_if(work_items_.begin(), work_items_.end(), finder);
 361   return it != work_items_.end() ? *it : NULL;
 362 }
 363
 364 // Changes a component's status, clearing on_demand and firing notifications as
 365 // necessary. By convention, this is the only function that can change a
 366 // CrxUpdateItem's |status|.
 367 // TODO(waffles): Do we want to add DCHECKS for valid state transitions here?
 368 void CrxUpdateService::ChangeItemState(CrxUpdateItem* item,
 369                                        CrxUpdateItem::Status to) {
 370   DCHECK(thread_checker_.CalledOnValidThread());
 371   if (to == CrxUpdateItem::kNoUpdate || to == CrxUpdateItem::kUpdated ||
 372       to == CrxUpdateItem::kUpToDate) {
 373     item->on_demand = false;
 374   }
 375
 376   item->status = to;
 377
 378   switch (to) {
 379     case CrxUpdateItem::kCanUpdate:
 380       NotifyObservers(Observer::COMPONENT_UPDATE_FOUND, item->id);
 381       break;
 382     case CrxUpdateItem::kUpdatingDiff:
 383     case CrxUpdateItem::kUpdating:
 384       NotifyObservers(Observer::COMPONENT_UPDATE_READY, item->id);
 385       break;
 386     case CrxUpdateItem::kUpdated:
 387       NotifyObservers(Observer::COMPONENT_UPDATED, item->id);
 388       break;
 389     case CrxUpdateItem::kUpToDate:
 390     case CrxUpdateItem::kNoUpdate:
 391       NotifyObservers(Observer::COMPONENT_NOT_UPDATED, item->id);
 392       break;
 393     case CrxUpdateItem::kNew:
 394     case CrxUpdateItem::kChecking:
 395     case CrxUpdateItem::kDownloading:
 396     case CrxUpdateItem::kDownloadingDiff:
 397     case CrxUpdateItem::kLastStatus:
 398       // No notification for these states.
 399       break;
 400   }
 401
 402   // Free possible pending network requests.
 403   if ((to == CrxUpdateItem::kUpdated) || (to == CrxUpdateItem::kUpToDate) ||
 404       (to == CrxUpdateItem::kNoUpdate)) {
 405     for (std::vector<base::Closure>::iterator it =
 406              item->ready_callbacks.begin();
 407          it != item->ready_callbacks.end();
 408          ++it) {
 409       it->Run();
 410     }
 411     item->ready_callbacks.clear();
 412   }
 413 }
 414
 415 // Changes all the components in |work_items_| that have |from| status to
 416 // |to| status and returns how many have been changed.
 417 size_t CrxUpdateService::ChangeItemStatus(CrxUpdateItem::Status from,
 418                                           CrxUpdateItem::Status to) {
 419   DCHECK(thread_checker_.CalledOnValidThread());
 420   size_t count = 0;
 421   for (UpdateItems::iterator it = work_items_.begin();
 422        it != work_items_.end();
 423        ++it) {
 424     CrxUpdateItem* item = *it;
 425     if (item->status == from) {
 426       ChangeItemState(item, to);
 427       ++count;
 428     }
 429   }
 430   return count;
 431 }
 432
 433 // Adds a component to be checked for upgrades. If the component exists it
 434 // it will be replaced and the return code is kReplaced.
 435 ComponentUpdateService::Status CrxUpdateService::RegisterComponent(
 436     const CrxComponent& component) {
 437   DCHECK(thread_checker_.CalledOnValidThread());
 438   if (component.pk_hash.empty() || !component.version.IsValid() ||
 439       !component.installer)
 440     return kError;
 441
 442   std::string id(GetCrxComponentID(component));
 443   CrxUpdateItem* uit = FindUpdateItemById(id);
 444   if (uit) {
 445     uit->component = component;
 446     return kReplaced;
 447   }
 448
 449   uit = new CrxUpdateItem;
 450   uit->id.swap(id);
 451   uit->component = component;
 452
 453   work_items_.push_back(uit);
 454
 455   // If this is the first component registered we call Start to
 456   // schedule the first timer. Otherwise, reset the timer to trigger another
 457   // pass over the work items, if the component updater is sleeping, fact
 458   // indicated by a running timer. If the timer is not running, it means that
 459   // the service is busy updating something, and in that case, this component
 460   // will be picked up at the next pass.
 461   if (running_) {
 462     if (work_items_.size() == 1) {
 463       Start();
 464     } else if (timer_.IsRunning()) {
 465         timer_.Start(FROM_HERE,
 466                      base::TimeDelta::FromSeconds(config_->InitialDelay()),
 467                      this,
 468                      &CrxUpdateService::ProcessPendingItems);
 469     }
 470   }
 471
 472   return kOk;
 473 }
 474
 475 std::vector<std::string> CrxUpdateService::GetComponentIDs() const {
 476   DCHECK(thread_checker_.CalledOnValidThread());
 477   std::vector<std::string> component_ids;
 478   for (UpdateItems::const_iterator it = work_items_.begin();
 479        it != work_items_.end();
 480        ++it) {
 481     const CrxUpdateItem* item = *it;
 482     component_ids.push_back(item->id);
 483   }
 484   return component_ids;
 485 }
 486
 487 OnDemandUpdater& CrxUpdateService::GetOnDemandUpdater() {
 488   return *this;
 489 }
 490
 491 void CrxUpdateService::MaybeThrottle(const std::string& crx_id,
 492                                      const base::Closure& callback) {
 493   DCHECK(thread_checker_.CalledOnValidThread());
 494   // Check if we can on-demand update, else unblock the request anyway.
 495   CrxUpdateItem* item = FindUpdateItemById(crx_id);
 496   Status status = OnDemandUpdateWithCooldown(item);
 497   if (status == kOk || status == kInProgress) {
 498     item->ready_callbacks.push_back(callback);
 499     return;
 500   }
 501   callback.Run();
 502 }
 503
 504 scoped_refptr<base::SequencedTaskRunner>
 505 CrxUpdateService::GetSequencedTaskRunner() {
 506   return config_->GetSequencedTaskRunner();
 507 }
 508
 509 bool CrxUpdateService::GetComponentDetails(const std::string& component_id,
 510                                            CrxUpdateItem* item) const {
 511   DCHECK(thread_checker_.CalledOnValidThread());
 512   const CrxUpdateItem* crx_update_item(FindUpdateItemById(component_id));
 513   if (crx_update_item)
 514     *item = *crx_update_item;
 515   return crx_update_item != NULL;
 516 }
 517
 518 // Start the process of checking for an update, for a particular component
 519 // that was previously registered.
 520 // |component_id| is a value returned from GetCrxComponentID().
 521 ComponentUpdateService::Status CrxUpdateService::OnDemandUpdate(
 522     const std::string& component_id) {
 523   return OnDemandUpdateInternal(FindUpdateItemById(component_id));
 524 }
 525
 526 // This is the main loop of the component updater. It updates one component
 527 // at a time if updates are available. Otherwise, it does an update check or
 528 // takes a long sleep until the loop runs again.
 529 void CrxUpdateService::ProcessPendingItems() {
 530   DCHECK(thread_checker_.CalledOnValidThread());
 531
 532   CrxUpdateItem* ready_upgrade = FindReadyComponent();
 533   if (ready_upgrade) {
 534     UpdateComponent(ready_upgrade);
 535     return;
 536   }
 537
 538   if (!CheckForUpdates())
 539     ScheduleNextRun(kStepDelayLong);
 540 }
 541
 542 CrxUpdateItem* CrxUpdateService::FindReadyComponent() const {
 543   class Helper {
 544    public:
 545     static bool IsReadyOnDemand(CrxUpdateItem* item) {
 546       return item->on_demand && IsReady(item);
 547     }
 548     static bool IsReady(CrxUpdateItem* item) {
 549       return item->status == CrxUpdateItem::kCanUpdate;
 550     }
 551   };
 552
 553   std::vector<CrxUpdateItem*>::const_iterator it = std::find_if(
 554       work_items_.begin(), work_items_.end(), Helper::IsReadyOnDemand);
 555   if (it != work_items_.end())
 556     return *it;
 557   it = std::find_if(work_items_.begin(), work_items_.end(), Helper::IsReady);
 558   if (it != work_items_.end())
 559     return *it;
 560   return NULL;
 561 }
 562
 563 // Prepares the components for an update check and initiates the request.
 564 // On demand components are always included in the update check request.
 565 // Otherwise, only include components that have not been checked recently.
 566 bool CrxUpdateService::CheckForUpdates() {
 567   const base::TimeDelta minimum_recheck_wait_time =
 568       base::TimeDelta::FromSeconds(config_->MinimumReCheckWait());
 569   const base::Time now(base::Time::Now());
 570
 571   std::vector<CrxUpdateItem*> items_to_check;
 572   for (size_t i = 0; i != work_items_.size(); ++i) {
 573     CrxUpdateItem* item = work_items_[i];
 574     DCHECK(item->status == CrxUpdateItem::kNew ||
 575            item->status == CrxUpdateItem::kNoUpdate ||
 576            item->status == CrxUpdateItem::kUpToDate ||
 577            item->status == CrxUpdateItem::kUpdated);
 578
 579     const base::TimeDelta time_since_last_checked(now - item->last_check);
 580
 581     if (!item->on_demand &&
 582         time_since_last_checked < minimum_recheck_wait_time) {
 583       VLOG(1) << "Skipping check for component update: id=" << item->id
 584               << ", time_since_last_checked="
 585               << time_since_last_checked.InSeconds()
 586               << " seconds: too soon to check for an update";
 587       continue;
 588     }
 589
 590     VLOG(1) << "Scheduling update check for component id=" << item->id
 591             << ", time_since_last_checked="
 592             << time_since_last_checked.InSeconds() << " seconds";
 593
 594     item->last_check = now;
 595     item->crx_urls.clear();
 596     item->crx_diffurls.clear();
 597     item->previous_version = item->component.version;
 598     item->next_version = Version();
 599     item->previous_fp = item->component.fingerprint;
 600     item->next_fp.clear();
 601     item->diff_update_failed = false;
 602     item->error_category = 0;
 603     item->error_code = 0;
 604     item->extra_code1 = 0;
 605     item->diff_error_category = 0;
 606     item->diff_error_code = 0;
 607     item->diff_extra_code1 = 0;
 608     item->download_metrics.clear();
 609
 610     items_to_check.push_back(item);
 611
 612     ChangeItemState(item, CrxUpdateItem::kChecking);
 613   }
 614
 615   if (items_to_check.empty())
 616     return false;
 617
 618   update_checker_ = UpdateChecker::Create(*config_).Pass();
 619   return update_checker_->CheckForUpdates(
 620       items_to_check,
 621       config_->ExtraRequestParams(),
 622       base::Bind(&CrxUpdateService::UpdateCheckComplete,
 623                  base::Unretained(this)));
 624 }
 625
 626 void CrxUpdateService::UpdateComponent(CrxUpdateItem* workitem) {
 627   scoped_ptr<CRXContext> crx_context(new CRXContext);
 628   crx_context->pk_hash = workitem->component.pk_hash;
 629   crx_context->id = workitem->id;
 630   crx_context->installer = workitem->component.installer;
 631   crx_context->fingerprint = workitem->next_fp;
 632   const std::vector<GURL>* urls = NULL;
 633   bool allow_background_download = false;
 634   if (CanTryDiffUpdate(workitem, *config_)) {
 635     urls = &workitem->crx_diffurls;
 636     ChangeItemState(workitem, CrxUpdateItem::kDownloadingDiff);
 637   } else {
 638     // Background downloads are enabled only for selected components and
 639     // only for full downloads (see issue 340448).
 640     allow_background_download = workitem->component.allow_background_download;
 641     urls = &workitem->crx_urls;
 642     ChangeItemState(workitem, CrxUpdateItem::kDownloading);
 643   }
 644
 645   // On demand component updates are always downloaded in foreground.
 646   const bool is_background_download = !workitem->on_demand &&
 647                                       allow_background_download &&
 648                                       config_->UseBackgroundDownloader();
 649
 650   crx_downloader_.reset(
 651       CrxDownloader::Create(is_background_download,
 652                             config_->RequestContext(),
 653                             blocking_task_runner_,
 654                             config_->GetSingleThreadTaskRunner()));
 655   crx_downloader_->set_progress_callback(
 656       base::Bind(&CrxUpdateService::DownloadProgress,
 657                  base::Unretained(this),
 658                  crx_context->id));
 659   crx_downloader_->StartDownload(*urls,
 660                                  base::Bind(&CrxUpdateService::DownloadComplete,
 661                                             base::Unretained(this),
 662                                             base::Passed(&crx_context)));
 663 }
 664
 665 void CrxUpdateService::UpdateCheckComplete(
 666     const GURL& original_url,
 667     int error,
 668     const std::string& error_message,
 669     const UpdateResponse::Results& results) {
 670   DCHECK(thread_checker_.CalledOnValidThread());
 671   VLOG(1) << "Update check completed from: " << original_url.spec();
 672   update_checker_.reset();
 673   if (!error)
 674     OnUpdateCheckSucceeded(results);
 675   else
 676     OnUpdateCheckFailed(error, error_message);
 677 }
 678
 679 // Handles a valid Omaha update check response by matching the results with
 680 // the registered components which were checked for updates.
 681 // If updates are found, prepare the components for the actual version upgrade.
 682 // One of these components will be drafted for the upgrade next time
 683 // ProcessPendingItems is called.
 684 void CrxUpdateService::OnUpdateCheckSucceeded(
 685     const UpdateResponse::Results& results) {
 686   size_t num_updates_pending = 0;
 687   DCHECK(thread_checker_.CalledOnValidThread());
 688   VLOG(1) << "Update check succeeded.";
 689   std::vector<UpdateResponse::Result>::const_iterator it;
 690   for (it = results.list.begin(); it != results.list.end(); ++it) {
 691     CrxUpdateItem* crx = FindUpdateItemById(it->extension_id);
 692     if (!crx)
 693       continue;
 694
 695     if (crx->status != CrxUpdateItem::kChecking) {
 696       NOTREACHED();
 697       continue;  // Not updating this component now.
 698     }
 699
 700     if (it->manifest.version.empty()) {
 701       // No version means no update available.
 702       ChangeItemState(crx, CrxUpdateItem::kNoUpdate);
 703       VLOG(1) << "No update available for component: " << crx->id;
 704       continue;
 705     }
 706
 707     if (!IsVersionNewer(crx->component.version, it->manifest.version)) {
 708       // The component is up to date.
 709       ChangeItemState(crx, CrxUpdateItem::kUpToDate);
 710       VLOG(1) << "Component already up-to-date: " << crx->id;
 711       continue;
 712     }
 713
 714     if (!it->manifest.browser_min_version.empty()) {
 715       if (IsVersionNewer(config_->GetBrowserVersion(),
 716                          it->manifest.browser_min_version)) {
 717         // The component is not compatible with this Chrome version.
 718         VLOG(1) << "Ignoring incompatible component: " << crx->id;
 719         ChangeItemState(crx, CrxUpdateItem::kNoUpdate);
 720         continue;
 721       }
 722     }
 723
 724     if (it->manifest.packages.size() != 1) {
 725       // Assume one and only one package per component.
 726       VLOG(1) << "Ignoring multiple packages for component: " << crx->id;
 727       ChangeItemState(crx, CrxUpdateItem::kNoUpdate);
 728       continue;
 729     }
 730
 731     // Parse the members of the result and queue an upgrade for this component.
 732     crx->next_version = Version(it->manifest.version);
 733
 734     VLOG(1) << "Update found for component: " << crx->id;
 735
 736     typedef UpdateResponse::Result::Manifest::Package Package;
 737     const Package& package(it->manifest.packages[0]);
 738     crx->next_fp = package.fingerprint;
 739
 740     // Resolve the urls by combining the base urls with the package names.
 741     for (size_t i = 0; i != it->crx_urls.size(); ++i) {
 742       const GURL url(it->crx_urls[i].Resolve(package.name));
 743       if (url.is_valid())
 744         crx->crx_urls.push_back(url);
 745     }
 746     for (size_t i = 0; i != it->crx_diffurls.size(); ++i) {
 747       const GURL url(it->crx_diffurls[i].Resolve(package.namediff));
 748       if (url.is_valid())
 749         crx->crx_diffurls.push_back(url);
 750     }
 751
 752     ChangeItemState(crx, CrxUpdateItem::kCanUpdate);
 753     ++num_updates_pending;
 754   }
 755
 756   // All components that are not included in the update response are
 757   // considered up to date.
 758   ChangeItemStatus(CrxUpdateItem::kChecking, CrxUpdateItem::kUpToDate);
 759
 760   // If there are updates pending we do a short wait, otherwise we take
 761   // a longer delay until we check the components again.
 762   ScheduleNextRun(num_updates_pending > 0 ? kStepDelayShort : kStepDelayLong);
 763 }
 764
 765 void CrxUpdateService::OnUpdateCheckFailed(int error,
 766                                            const std::string& error_message) {
 767   DCHECK(thread_checker_.CalledOnValidThread());
 768   DCHECK(error);
 769   size_t count =
 770       ChangeItemStatus(CrxUpdateItem::kChecking, CrxUpdateItem::kNoUpdate);
 771   DCHECK_GT(count, 0ul);
 772   VLOG(1) << "Update check failed.";
 773   ScheduleNextRun(kStepDelayLong);
 774 }
 775
 776 // Called when progress is being made downloading a CRX. The progress may
 777 // not monotonically increase due to how the CRX downloader switches between
 778 // different downloaders and fallback urls.
 779 void CrxUpdateService::DownloadProgress(
 780     const std::string& component_id,
 781     const CrxDownloader::Result& download_result) {
 782   DCHECK(thread_checker_.CalledOnValidThread());
 783   NotifyObservers(Observer::COMPONENT_UPDATE_DOWNLOADING, component_id);
 784 }
 785
 786 // Called when the CRX package has been downloaded to a temporary location.
 787 // Here we fire the notifications and schedule the component-specific installer
 788 // to be called in the file thread.
 789 void CrxUpdateService::DownloadComplete(
 790     scoped_ptr<CRXContext> crx_context,
 791     const CrxDownloader::Result& download_result) {
 792   DCHECK(thread_checker_.CalledOnValidThread());
 793
 794   CrxUpdateItem* crx = FindUpdateItemById(crx_context->id);
 795   DCHECK(crx->status == CrxUpdateItem::kDownloadingDiff ||
 796          crx->status == CrxUpdateItem::kDownloading);
 797
 798   AppendDownloadMetrics(crx_downloader_->download_metrics(),
 799                         &crx->download_metrics);
 800
 801   crx_downloader_.reset();
 802
 803   if (download_result.error) {
 804     if (crx->status == CrxUpdateItem::kDownloadingDiff) {
 805       crx->diff_error_category = kNetworkError;
 806       crx->diff_error_code = download_result.error;
 807       crx->diff_update_failed = true;
 808       size_t count = ChangeItemStatus(CrxUpdateItem::kDownloadingDiff,
 809                                       CrxUpdateItem::kCanUpdate);
 810       DCHECK_EQ(count, 1ul);
 811
 812       ScheduleNextRun(kStepDelayShort);
 813       return;
 814     }
 815     crx->error_category = kNetworkError;
 816     crx->error_code = download_result.error;
 817     size_t count =
 818         ChangeItemStatus(CrxUpdateItem::kDownloading, CrxUpdateItem::kNoUpdate);
 819     DCHECK_EQ(count, 1ul);
 820
 821     // At this point, since both the differential and the full downloads failed,
 822     // the update for this component has finished with an error.
 823     ping_manager_->OnUpdateComplete(crx);
 824
 825     // Move on to the next update, if there is one available.
 826     ScheduleNextRun(kStepDelayMedium);
 827   } else {
 828     size_t count = 0;
 829     if (crx->status == CrxUpdateItem::kDownloadingDiff) {
 830       count = ChangeItemStatus(CrxUpdateItem::kDownloadingDiff,
 831                                CrxUpdateItem::kUpdatingDiff);
 832     } else {
 833       count = ChangeItemStatus(CrxUpdateItem::kDownloading,
 834                                CrxUpdateItem::kUpdating);
 835     }
 836     DCHECK_EQ(count, 1ul);
 837
 838     // Why unretained? See comment at top of file.
 839     blocking_task_runner_->PostDelayedTask(
 840         FROM_HERE,
 841         base::Bind(&CrxUpdateService::Install,
 842                    base::Unretained(this),
 843                    base::Passed(&crx_context),
 844                    download_result.response),
 845         base::TimeDelta::FromMilliseconds(config_->StepDelay()));
 846   }
 847 }
 848
 849 // Install consists of digital signature verification, unpacking and then
 850 // calling the component specific installer. All that is handled by the
 851 // |unpacker_|. If there is an error this function is in charge of deleting
 852 // the files created.
 853 void CrxUpdateService::Install(scoped_ptr<CRXContext> context,
 854                                const base::FilePath& crx_path) {
 855   // This function owns the file at |crx_path| and the |context| object.
 856   unpacker_ = new ComponentUnpacker(context->pk_hash,
 857                                     crx_path,
 858                                     context->fingerprint,
 859                                     context->installer,
 860                                     config_->CreateOutOfProcessPatcher(),
 861                                     blocking_task_runner_);
 862   unpacker_->Unpack(base::Bind(&CrxUpdateService::EndUnpacking,
 863                                base::Unretained(this),
 864                                context->id,
 865                                crx_path));
 866 }
 867
 868 void CrxUpdateService::EndUnpacking(const std::string& component_id,
 869                                     const base::FilePath& crx_path,
 870                                     ComponentUnpacker::Error error,
 871                                     int extended_error) {
 872   if (!DeleteFileAndEmptyParentDirectory(crx_path))
 873     NOTREACHED() << crx_path.value();
 874   main_task_runner_->PostDelayedTask(
 875       FROM_HERE,
 876       base::Bind(&CrxUpdateService::DoneInstalling,
 877                  base::Unretained(this),
 878                  component_id,
 879                  error,
 880                  extended_error),
 881       base::TimeDelta::FromMilliseconds(config_->StepDelay()));
 882   // Reset the unpacker last, otherwise we free our own arguments.
 883   unpacker_ = NULL;
 884 }
 885
 886 // Installation has been completed. Adjust the component status and
 887 // schedule the next check. Schedule a short delay before trying the full
 888 // update when the differential update failed.
 889 void CrxUpdateService::DoneInstalling(const std::string& component_id,
 890                                       ComponentUnpacker::Error error,
 891                                       int extra_code) {
 892   DCHECK(thread_checker_.CalledOnValidThread());
 893
 894   ErrorCategory error_category = kErrorNone;
 895   switch (error) {
 896     case ComponentUnpacker::kNone:
 897       break;
 898     case ComponentUnpacker::kInstallerError:
 899       error_category = kInstallError;
 900       break;
 901     default:
 902       error_category = kUnpackError;
 903       break;
 904   }
 905
 906   const bool is_success = error == ComponentUnpacker::kNone;
 907
 908   CrxUpdateItem* item = FindUpdateItemById(component_id);
 909   if (item->status == CrxUpdateItem::kUpdatingDiff && !is_success) {
 910     item->diff_error_category = error_category;
 911     item->diff_error_code = error;
 912     item->diff_extra_code1 = extra_code;
 913     item->diff_update_failed = true;
 914     size_t count = ChangeItemStatus(CrxUpdateItem::kUpdatingDiff,
 915                                     CrxUpdateItem::kCanUpdate);
 916     DCHECK_EQ(count, 1ul);
 917     ScheduleNextRun(kStepDelayShort);
 918     return;
 919   }
 920
 921   if (is_success) {
 922     item->component.version = item->next_version;
 923     item->component.fingerprint = item->next_fp;
 924     ChangeItemState(item, CrxUpdateItem::kUpdated);
 925   } else {
 926     item->error_category = error_category;
 927     item->error_code = error;
 928     item->extra_code1 = extra_code;
 929     ChangeItemState(item, CrxUpdateItem::kNoUpdate);
 930   }
 931
 932   ping_manager_->OnUpdateComplete(item);
 933
 934   // Move on to the next update, if there is one available.
 935   ScheduleNextRun(kStepDelayMedium);
 936 }
 937
 938 void CrxUpdateService::NotifyObservers(Observer::Events event,
 939                                        const std::string& id) {
 940   DCHECK(thread_checker_.CalledOnValidThread());
 941   FOR_EACH_OBSERVER(Observer, observer_list_, OnEvent(event, id));
 942 }
 943
 944 ComponentUpdateService::Status CrxUpdateService::OnDemandUpdateWithCooldown(
 945     CrxUpdateItem* uit) {
 946   if (!uit)
 947     return kError;
 948
 949   // Check if the request is too soon.
 950   base::TimeDelta delta = base::Time::Now() - uit->last_check;
 951   if (delta < base::TimeDelta::FromSeconds(config_->OnDemandDelay()))
 952     return kError;
 953
 954   return OnDemandUpdateInternal(uit);
 955 }
 956
 957 ComponentUpdateService::Status CrxUpdateService::OnDemandUpdateInternal(
 958     CrxUpdateItem* uit) {
 959   if (!uit)
 960     return kError;
 961
 962   uit->on_demand = true;
 963
 964   // If there is an update available for this item, then continue processing
 965   // the update. This is an artifact of how update checks are done: in addition
 966   // to the on-demand item, the update check may include other items as well.
 967   if (uit->status != CrxUpdateItem::kCanUpdate) {
 968     Status service_status = GetServiceStatus(uit->status);
 969     // If the item is already in the process of being updated, there is
 970     // no point in this call, so return kInProgress.
 971     if (service_status == kInProgress)
 972       return service_status;
 973
 974     // Otherwise the item was already checked a while back (or it is new),
 975     // set its status to kNew to give it a slightly higher priority.
 976     ChangeItemState(uit, CrxUpdateItem::kNew);
 977   }
 978
 979   // In case the current delay is long, set the timer to a shorter value
 980   // to get the ball rolling.
 981   if (timer_.IsRunning()) {
 982     timer_.Stop();
 983     timer_.Start(FROM_HERE,
 984                  base::TimeDelta::FromSeconds(config_->StepDelay()),
 985                  this,
 986                  &CrxUpdateService::ProcessPendingItems);
 987   }
 988
 989   return kOk;
 990 }
 991
 992 ComponentUpdateService::Status CrxUpdateService::GetServiceStatus(
 993     CrxUpdateItem::Status status) {
 994   switch (status) {
 995     case CrxUpdateItem::kChecking:
 996     case CrxUpdateItem::kCanUpdate:
 997     case CrxUpdateItem::kDownloadingDiff:
 998     case CrxUpdateItem::kDownloading:
 999     case CrxUpdateItem::kUpdatingDiff:
1000     case CrxUpdateItem::kUpdating:
1001       return kInProgress;
1002     case CrxUpdateItem::kNew:
1003     case CrxUpdateItem::kUpdated:
1004     case CrxUpdateItem::kUpToDate:
1005     case CrxUpdateItem::kNoUpdate:
1006       return kOk;
1007     case CrxUpdateItem::kLastStatus:
1008       NOTREACHED() << status;
1009   }
1010   return kError;
1011 }
1012
1013 ///////////////////////////////////////////////////////////////////////////////
1014
1015 // The component update factory. Using the component updater as a singleton
1016 // is the job of the browser process.
1017 ComponentUpdateService* ComponentUpdateServiceFactory(Configurator* config) {
1018   DCHECK(config);
1019   return new CrxUpdateService(config);
1020 }
1021
1022 }  // namespace component_updater