Reland: Initialize and reset V4LocalDBManager. Instantiate V4Stores.

components/safe_browsing_db/v4_local_database_manager.h

 // Copyright 2016 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.
 
 #ifndef COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_
 #define COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_
 
 // A class that provides the interface between the SafeBrowsing protocol manager
 // and database that holds the downloaded updates.
 
 #include <memory>
 
 #include "components/safe_browsing_db/database_manager.h"
 #include "components/safe_browsing_db/hit_report.h"
 #include "components/safe_browsing_db/v4_database.h"
 #include "components/safe_browsing_db/v4_protocol_manager_util.h"
 #include "components/safe_browsing_db/v4_update_protocol_manager.h"
 #include "url/gurl.h"
 
 using content::ResourceType;
 
 namespace safe_browsing {
 
 // Manages the local, on-disk database of updates downloaded from the
 // SafeBrowsing service and interfaces with the protocol manager.
 class V4LocalDatabaseManager : public SafeBrowsingDatabaseManager {
  public:
   // Construct V4LocalDatabaseManager.
   // Must be initialized by calling StartOnIOThread() before using.
-  V4LocalDatabaseManager();
+  V4LocalDatabaseManager(const base::FilePath& base_path);
 
   //
   // SafeBrowsingDatabaseManager implementation
   //
 
   bool IsSupported() const override;
   safe_browsing::ThreatSource GetThreatSource() const override;
   bool ChecksAreAlwaysAsync() const override;
   bool CanCheckResourceType(content::ResourceType resource_type) const override;
   bool CanCheckUrl(const GURL& url) const override;
   bool IsDownloadProtectionEnabled() const override;
   bool CheckBrowseUrl(const GURL& url, Client* client) override;
   void CancelCheck(Client* client) override;
-  void StartOnIOThread(
-      net::URLRequestContextGetter* request_context_getter,
-      const V4ProtocolConfig& config) override;
+  void StartOnIOThread(net::URLRequestContextGetter* request_context_getter,
+                       const V4ProtocolConfig& config) override;
   void StopOnIOThread(bool shutdown) override;
   bool CheckDownloadUrl(const std::vector<GURL>& url_chain,
                         Client* client) override;
   bool CheckExtensionIDs(const std::set<std::string>& extension_ids,
                          Client* client) override;
   bool MatchCsdWhitelistUrl(const GURL& url) override;
   bool MatchMalwareIP(const std::string& ip_address) override;
   bool MatchDownloadWhitelistUrl(const GURL& url) override;
   bool MatchDownloadWhitelistString(const std::string& str) override;
   bool MatchInclusionWhitelistUrl(const GURL& url) override;
   bool MatchModuleWhitelistString(const std::string& str) override;
   bool CheckResourceUrl(const GURL& url, Client* client) override;
   bool IsMalwareKillSwitchOn() override;
   bool IsCsdWhitelistKillSwitchOn() override;
 
  private:
   ~V4LocalDatabaseManager() override;
 
   // The callback called each time the protocol manager downloads updates
   // successfully.
   void UpdateRequestCompleted(const std::vector<ListUpdateResponse>& responses);
 
+  void SetupUpdateProtocolManager(
+      net::URLRequestContextGetter* request_context_getter,
+      const V4ProtocolConfig& config);
+
+  void SetupDatabase();
+
+  void DatabaseReady(std::unique_ptr<V4Database> v4_database);
+
+  void OnCloseDatabase();
+
+  // The base directory under which to create the files that contain hashes.
+  const base::FilePath base_path_;
+
+  // Whether the service is running.
   bool enabled_;
 
   // Stores the current status of the lists to download from the SafeBrowsing
   // servers.
   // TODO(vakh): current_list_states_ doesn't really belong here.
   // It should come through the database, from the various V4Stores.
   base::hash_map<UpdateListIdentifier, std::string> current_list_states_;
 
   // The protocol manager that downloads the hash prefix updates.
   std::unique_ptr<V4UpdateProtocolManager> v4_update_protocol_manager_;
 
   // The database that manages the stores containing the hash prefix updates.
+  // All writes to this variable must happen on the IO thread only.
   std::unique_ptr<V4Database> v4_database_;
 
+  // The sequenced task runner for running safe browsing database operations.
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+
   friend class base::RefCountedThreadSafe<V4LocalDatabaseManager>;
   DISALLOW_COPY_AND_ASSIGN(V4LocalDatabaseManager);
 };  // class V4LocalDatabaseManager
 
 }  // namespace safe_browsing
 
 #endif  // COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_