Componentize component_updater: Split content::ResourceThrottle from CUS.

chrome/browser/component_updater/component_updater_service.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/component_updater/component_updater_service.h"
 
 #include <algorithm>
 #include <set>
 #include <vector>
 
 #include "base/at_exit.h"
 #include "base/bind.h"
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/observer_list.h"
 #include "base/sequenced_task_runner.h"
 #include "base/stl_util.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/timer.h"
-#include "chrome/browser/browser_process.h"
 #include "chrome/browser/component_updater/component_unpacker.h"
 #include "chrome/browser/component_updater/component_updater_configurator.h"
 #include "chrome/browser/component_updater/component_updater_ping_manager.h"
 #include "chrome/browser/component_updater/component_updater_utils.h"
 #include "chrome/browser/component_updater/crx_downloader.h"
 #include "chrome/browser/component_updater/crx_update_item.h"
 #include "chrome/browser/component_updater/update_checker.h"
 #include "chrome/browser/component_updater/update_response.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/public/browser/resource_controller.h"
-#include "content/public/browser/resource_throttle.h"
 #include "url/gurl.h"
 
-using content::BrowserThread;
-
 namespace component_updater {
 
 // The component updater is designed to live until process shutdown, so
 // base::Bind() calls are not refcounted.
 
 namespace {
 
 // Returns true if the |proposed| version is newer than |current| version.
 bool IsVersionNewer(const Version& current, const std::string& proposed) {
   Version proposed_ver(proposed);
@@ skipping 31 matching lines @@
 CrxUpdateItem::~CrxUpdateItem() {
 }
 
 CrxComponent::CrxComponent()
     : installer(NULL), allow_background_download(true) {
 }
 
 CrxComponent::~CrxComponent() {
 }
 
-///////////////////////////////////////////////////////////////////////////////
-// In charge of blocking url requests until the |crx_id| component has been
-// updated. This class is touched solely from the IO thread. The UI thread
-// can post tasks to it via weak pointers. By default the request is blocked
-// unless the CrxUpdateService calls Unblock().
-// The lifetime is controlled by Chrome's resource loader so the component
-// updater cannot touch objects from this class except via weak pointers.
-class CUResourceThrottle : public content::ResourceThrottle,
-                           public base::SupportsWeakPtr<CUResourceThrottle> {
- public:
-  explicit CUResourceThrottle(const net::URLRequest* request);
-  virtual ~CUResourceThrottle();
-
-  // Overriden from ResourceThrottle.
-  virtual void WillStartRequest(bool* defer) OVERRIDE;
-  virtual void WillRedirectRequest(const GURL& new_url, bool* defer) OVERRIDE;
-  virtual const char* GetNameForLogging() const OVERRIDE;
-
-  // Component updater calls this function via PostTask to unblock the request.
-  void Unblock();
-
-  typedef std::vector<base::WeakPtr<CUResourceThrottle> > WeakPtrVector;
-
- private:
-  enum State { NEW, BLOCKED, UNBLOCKED };
-
-  State state_;
-};
-
-void UnblockResourceThrottle(base::WeakPtr<CUResourceThrottle> rt) {
-  BrowserThread::PostTask(BrowserThread::IO,
-                          FROM_HERE,
-                          base::Bind(&CUResourceThrottle::Unblock, rt));
-}
-
-void UnblockandReapAllThrottles(CUResourceThrottle::WeakPtrVector* throttles) {
-  CUResourceThrottle::WeakPtrVector::iterator it;
-  for (it = throttles->begin(); it != throttles->end(); ++it)
-    UnblockResourceThrottle(*it);
-  throttles->clear();
-}
-
 //////////////////////////////////////////////////////////////////////////////
 // The one and only implementation of the ComponentUpdateService interface. In
 // charge of running the show. The main method is ProcessPendingItems() which
 // is called periodically to do the upgrades/installs or the update checks.
 // An important consideration here is to be as "low impact" as we can to the
 // rest of the browser, so even if we have many components registered and
 // eligible for update, we only do one thing at a time with pauses in between
 // the tasks. Also when we do network requests there is only one |url_fetcher_|
 // in flight at a time.
 // There are no locks in this code, the main structure |work_items_| is mutated
 // only from the main thread. The unpack and installation is done in a blocking
 // pool thread. The network requests are done in the IO thread or in the file
 // thread.
-class CrxUpdateService : public ComponentUpdateService, public OnDemandUpdater {
+class CrxUpdateService : public ComponentUpdateService {
  public:
   explicit CrxUpdateService(Configurator* config);
   virtual ~CrxUpdateService();
 
   // Overrides for ComponentUpdateService.
   virtual void AddObserver(Observer* observer) OVERRIDE;
   virtual void RemoveObserver(Observer* observer) OVERRIDE;
   virtual Status Start() OVERRIDE;
   virtual Status Stop() OVERRIDE;
   virtual Status RegisterComponent(const CrxComponent& component) OVERRIDE;
   virtual std::vector<std::string> GetComponentIDs() const OVERRIDE;
   virtual bool GetComponentDetails(const std::string& component_id,
                                    CrxUpdateItem* item) const OVERRIDE;
-  virtual OnDemandUpdater& GetOnDemandUpdater() OVERRIDE;
   virtual scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner()
       OVERRIDE;
 
-  // Overrides for OnDemandUpdater.
-  virtual content::ResourceThrottle* GetOnDemandResourceThrottle(
-      net::URLRequest* request,
-      const std::string& crx_id) OVERRIDE;
-  virtual Status OnDemandUpdate(const std::string& component_id) OVERRIDE;
-
   // Context for a crx download url request.
   struct CRXContext {
     ComponentInstaller* installer;
     std::vector<uint8> pk_hash;
     std::string id;
     std::string fingerprint;
     CRXContext() : installer(NULL) {}
   };
 
  private:
   enum ErrorCategory {
     kErrorNone = 0,
     kNetworkError,
     kUnpackError,
     kInstallError,
   };
 
   enum StepDelayInterval {
     kStepDelayShort = 0,
     kStepDelayMedium,
     kStepDelayLong,
   };
 
+  // Overrides for ComponentUpdateService.
+  virtual void MaybeThrottle(const std::string& crx_id,
+                             const base::Closure& callback) OVERRIDE;
+  virtual ComponentUpdateService::Status OnDemandUpdate(
+      const std::string& component_id) OVERRIDE;
+
   void UpdateCheckComplete(int error,
                            const std::string& error_message,
                            const UpdateResponse::Results& results);
   void OnUpdateCheckSucceeded(const UpdateResponse::Results& results);
   void OnUpdateCheckFailed(int error, const std::string& error_message);
 
   void DownloadProgress(const std::string& component_id,
                         const CrxDownloader::Result& download_result);
 
   void DownloadComplete(scoped_ptr<CRXContext> crx_context,
@@ skipping 32 matching lines @@
   void ChangeItemState(CrxUpdateItem* item, CrxUpdateItem::Status to);
 
   size_t ChangeItemStatus(CrxUpdateItem::Status from, CrxUpdateItem::Status to);
 
   CrxUpdateItem* FindUpdateItemById(const std::string& id) const;
 
   void NotifyObservers(Observer::Events event, const std::string& id);
 
   bool HasOnDemandItems() const;
 
-  void OnNewResourceThrottle(base::WeakPtr<CUResourceThrottle> rt,
-                             const std::string& crx_id);
-
   Status GetServiceStatus(const CrxUpdateItem::Status status);
 
   scoped_ptr<Configurator> config_;
 
   scoped_ptr<UpdateChecker> update_checker_;
 
   scoped_ptr<PingManager> ping_manager_;
 
   scoped_refptr<ComponentUnpacker> unpacker_;
 
@@ skipping 182 matching lines @@
     case CrxUpdateItem::kDownloading:
     case CrxUpdateItem::kDownloadingDiff:
     case CrxUpdateItem::kLastStatus:
       // No notification for these states.
       break;
   }
 
   // Free possible pending network requests.
   if ((to == CrxUpdateItem::kUpdated) || (to == CrxUpdateItem::kUpToDate) ||
       (to == CrxUpdateItem::kNoUpdate)) {
-    UnblockandReapAllThrottles(&item->throttles);
+    for (std::vector<base::Closure>::iterator it =
+             item->ready_callbacks.begin();
+         it != item->ready_callbacks.end();
+         ++it) {
+      it->Run();
+    }
+    item->ready_callbacks.clear();
   }
 }
 
 // Changes all the components in |work_items_| that have |from| status to
 // |to| status and returns how many have been changed.
 size_t CrxUpdateService::ChangeItemStatus(CrxUpdateItem::Status from,
                                           CrxUpdateItem::Status to) {
   DCHECK(thread_checker_.CalledOnValidThread());
   size_t count = 0;
   for (UpdateItems::iterator it = work_items_.begin();
@@ skipping 64 matching lines @@
 
 bool CrxUpdateService::GetComponentDetails(const std::string& component_id,
                                            CrxUpdateItem* item) const {
   DCHECK(thread_checker_.CalledOnValidThread());
   const CrxUpdateItem* crx_update_item(FindUpdateItemById(component_id));
   if (crx_update_item)
     *item = *crx_update_item;
   return crx_update_item != NULL;
 }
 
-OnDemandUpdater& CrxUpdateService::GetOnDemandUpdater() {
-  return *this;
-}
-
 scoped_refptr<base::SequencedTaskRunner>
 CrxUpdateService::GetSequencedTaskRunner() {
   return config_->GetSequencedTaskRunner();
 }
 
+void CrxUpdateService::MaybeThrottle(const std::string& crx_id,
+                                     const base::Closure& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  // Check if we can on-demand update, else unblock the request anyway.
+  CrxUpdateItem* item = FindUpdateItemById(crx_id);
+  Status status = OnDemandUpdateWithCooldown(item);
+  if (status == kOk || status == kInProgress) {
+    item->ready_callbacks.push_back(callback);
+    return;
+  }
+  callback.Run();
+}
+
+// Start the process of checking for an update, for a particular component
+// that was previously registered.
+// |component_id| is a value returned from GetCrxComponentID().
+ComponentUpdateService::Status CrxUpdateService::OnDemandUpdate(
+    const std::string& component_id) {
+  return OnDemandUpdateInternal(FindUpdateItemById(component_id));
+}
+
 // This is the main loop of the component updater. It updates one component
 // at a time if updates are available. Otherwise, it does an update check or
 // takes a long sleep until the loop runs again.
 void CrxUpdateService::ProcessPendingItems() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   CrxUpdateItem* ready_upgrade = FindReadyComponent();
   if (ready_upgrade) {
     UpdateComponent(ready_upgrade);
     return;
@@ skipping 396 matching lines @@
   // Move on to the next update, if there is one available.
   ScheduleNextRun(kStepDelayMedium);
 }
 
 void CrxUpdateService::NotifyObservers(Observer::Events event,
                                        const std::string& id) {
   DCHECK(thread_checker_.CalledOnValidThread());
   FOR_EACH_OBSERVER(Observer, observer_list_, OnEvent(event, id));
 }
 
-content::ResourceThrottle* CrxUpdateService::GetOnDemandResourceThrottle(
-    net::URLRequest* request,
-    const std::string& crx_id) {
-  // We give the raw pointer to the caller, who will delete it at will
-  // and we keep for ourselves a weak pointer to it so we can post tasks
-  // from the UI thread without having to track lifetime directly.
-  CUResourceThrottle* rt = new CUResourceThrottle(request);
-  main_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&CrxUpdateService::OnNewResourceThrottle,
-                 base::Unretained(this), rt->AsWeakPtr(), crx_id));
-  return rt;
-}
-
-void CrxUpdateService::OnNewResourceThrottle(
-    base::WeakPtr<CUResourceThrottle> rt,
-    const std::string& crx_id) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  // Check if we can on-demand update, else unblock the request anyway.
-  CrxUpdateItem* item = FindUpdateItemById(crx_id);
-  Status status = OnDemandUpdateWithCooldown(item);
-  if (status == kOk || status == kInProgress) {
-    item->throttles.push_back(rt);
-    return;
-  }
-  UnblockResourceThrottle(rt);
-}
-
-// Start the process of checking for an update, for a particular component
-// that was previously registered.
-// |component_id| is a value returned from GetCrxComponentID().
-ComponentUpdateService::Status CrxUpdateService::OnDemandUpdate(
-    const std::string& component_id) {
-  return OnDemandUpdateInternal(FindUpdateItemById(component_id));
-}
-
 ComponentUpdateService::Status CrxUpdateService::OnDemandUpdateWithCooldown(
     CrxUpdateItem* uit) {
   if (!uit)
     return kError;
 
   // Check if the request is too soon.
   base::TimeDelta delta = base::Time::Now() - uit->last_check;
   if (delta < base::TimeDelta::FromSeconds(config_->OnDemandDelay()))
     return kError;
 
@@ skipping 51 matching lines @@
     case CrxUpdateItem::kNoUpdate:
       return kOk;
     case CrxUpdateItem::kLastStatus:
       NOTREACHED() << status;
   }
   return kError;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
-CUResourceThrottle::CUResourceThrottle(const net::URLRequest* request)
-    : state_(NEW) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-}
-
-CUResourceThrottle::~CUResourceThrottle() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-}
-
-void CUResourceThrottle::WillStartRequest(bool* defer) {
-  if (state_ != UNBLOCKED) {
-    state_ = BLOCKED;
-    *defer = true;
-  } else {
-    *defer = false;
-  }
-}
-
-void CUResourceThrottle::WillRedirectRequest(const GURL& new_url, bool* defer) {
-  WillStartRequest(defer);
-}
-
-const char* CUResourceThrottle::GetNameForLogging() const {
-  return "ComponentUpdateResourceThrottle";
-}
-
-void CUResourceThrottle::Unblock() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  if (state_ == BLOCKED)
-    controller()->Resume();
-  state_ = UNBLOCKED;
-}
-
 // The component update factory. Using the component updater as a singleton
 // is the job of the browser process.
 ComponentUpdateService* ComponentUpdateServiceFactory(Configurator* config) {
   DCHECK(config);
   return new CrxUpdateService(config);
 }
 
 }  // namespace component_updater