chrome/browser/browsing_data/browsing_data_database_helper.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_DATABASE_HELPER_H_
   6 #define CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_DATABASE_HELPER_H_
   7
   8 #include <list>
   9 #include <set>
  10 #include <string>
  11
  12 #include "base/callback.h"
  13 #include "base/compiler_specific.h"
  14 #include "base/memory/ref_counted.h"
  15 #include "base/synchronization/lock.h"
  16 #include "chrome/common/url_constants.h"
  17 #include "storage/browser/database/database_tracker.h"
  18 #include "storage/common/database/database_identifier.h"
  19 #include "url/gurl.h"
  20
  21 class Profile;
  22
  23 // This class fetches database information in the FILE thread, and notifies
  24 // the UI thread upon completion.
  25 // A client of this class need to call StartFetching from the UI thread to
  26 // initiate the flow, and it'll be notified by the callback in its UI
  27 // thread at some later point.
  28 class BrowsingDataDatabaseHelper
  29     : public base::RefCountedThreadSafe<BrowsingDataDatabaseHelper> {
  30  public:
  31   // Contains detailed information about a web database.
  32   struct DatabaseInfo {
  33     DatabaseInfo(const storage::DatabaseIdentifier& identifier,
  34                  const std::string& database_name,
  35                  const std::string& description,
  36                  int64 size,
  37                  base::Time last_modified);
  38     ~DatabaseInfo();
  39
  40     storage::DatabaseIdentifier identifier;
  41     std::string database_name;
  42     std::string description;
  43     int64 size;
  44     base::Time last_modified;
  45   };
  46
  47   explicit BrowsingDataDatabaseHelper(Profile* profile);
  48
  49   // Starts the fetching process, which will notify its completion via
  50   // callback.
  51   // This must be called only in the UI thread.
  52   virtual void StartFetching(
  53       const base::Callback<void(const std::list<DatabaseInfo>&)>& callback);
  54
  55   // Requests a single database to be deleted in the FILE thread. This must be
  56   // called in the UI thread.
  57   virtual void DeleteDatabase(const std::string& origin_identifier,
  58                               const std::string& name);
  59
  60  protected:
  61   friend class base::RefCountedThreadSafe<BrowsingDataDatabaseHelper>;
  62   virtual ~BrowsingDataDatabaseHelper();
  63
  64   // Notifies the completion callback. This must be called in the UI thread.
  65   void NotifyInUIThread();
  66
  67   // Access to |database_info_| is triggered indirectly via the UI thread and
  68   // guarded by |is_fetching_|. This means |database_info_| is only accessed
  69   // while |is_fetching_| is true. The flag |is_fetching_| is only accessed on
  70   // the UI thread.
  71   // In the context of this class |database_info_| is only accessed on the FILE
  72   // thread.
  73   std::list<DatabaseInfo> database_info_;
  74
  75   // This member is only mutated on the UI thread.
  76   base::Callback<void(const std::list<DatabaseInfo>&)> completion_callback_;
  77
  78   // Indicates whether or not we're currently fetching information:
  79   // it's true when StartFetching() is called in the UI thread, and it's reset
  80   // after we notify the callback in the UI thread.
  81   // This member is only mutated on the UI thread.
  82   bool is_fetching_;
  83
  84  private:
  85   // Enumerates all databases. This must be called in the FILE thread.
  86   void FetchDatabaseInfoOnFileThread();
  87
  88   // Delete a single database file. This must be called in the FILE thread.
  89   void DeleteDatabaseOnFileThread(const std::string& origin,
  90                                   const std::string& name);
  91
  92   scoped_refptr<storage::DatabaseTracker> tracker_;
  93
  94   DISALLOW_COPY_AND_ASSIGN(BrowsingDataDatabaseHelper);
  95 };
  96
  97 // This class is a thin wrapper around BrowsingDataDatabaseHelper that does not
  98 // fetch its information from the database tracker, but gets them passed as
  99 // a parameter during construction.
 100 class CannedBrowsingDataDatabaseHelper : public BrowsingDataDatabaseHelper {
 101  public:
 102   struct PendingDatabaseInfo {
 103     PendingDatabaseInfo(const GURL& origin,
 104                         const std::string& name,
 105                         const std::string& description);
 106     ~PendingDatabaseInfo();
 107
 108     // The operator is needed to store |PendingDatabaseInfo| objects in a set.
 109     bool operator<(const PendingDatabaseInfo& other) const;
 110
 111     GURL origin;
 112     std::string name;
 113     std::string description;
 114   };
 115
 116   explicit CannedBrowsingDataDatabaseHelper(Profile* profile);
 117
 118   // Add a database to the set of canned databases that is returned by this
 119   // helper.
 120   void AddDatabase(const GURL& origin,
 121                    const std::string& name,
 122                    const std::string& description);
 123
 124   // Clear the list of canned databases.
 125   void Reset();
 126
 127   // True if no databases are currently stored.
 128   bool empty() const;
 129
 130   // Returns the number of currently stored databases.
 131   size_t GetDatabaseCount() const;
 132
 133   // Returns the current list of web databases.
 134   const std::set<PendingDatabaseInfo>& GetPendingDatabaseInfo();
 135
 136   // BrowsingDataDatabaseHelper implementation.
 137   void StartFetching(const base::Callback<void(const std::list<DatabaseInfo>&)>&
 138                          callback) override;
 139   void DeleteDatabase(const std::string& origin_identifier,
 140                       const std::string& name) override;
 141
 142  private:
 143   ~CannedBrowsingDataDatabaseHelper() override;
 144
 145   std::set<PendingDatabaseInfo> pending_database_info_;
 146
 147   DISALLOW_COPY_AND_ASSIGN(CannedBrowsingDataDatabaseHelper);
 148 };
 149
 150 #endif  // CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_DATABASE_HELPER_H_