chrome/browser/sync_file_system/drive_backend/remote_change_handler.h

   1 // Copyright 2013 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_SYNC_FILE_SYSTEM_DRIVE_BACKEND_REMOTE_CHANGE_HANDLER_H_
   6 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_REMOTE_CHANGE_HANDLER_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <string>
  11 #include <utility>
  12
  13 #include "base/files/file_path.h"
  14 #include "base/stl_util.h"
  15 #include "base/time/time.h"
  16 #include "webkit/browser/fileapi/file_system_url.h"
  17 #include "webkit/browser/fileapi/syncable/file_change.h"
  18
  19 namespace sync_file_system {
  20
  21 // Manages pending remote file changes.
  22 class RemoteChangeHandler {
  23  public:
  24   struct RemoteChange {
  25     int64 changestamp;
  26     std::string resource_id;
  27     std::string md5_checksum;
  28     base::Time updated_time;
  29     fileapi::FileSystemURL url;
  30     FileChange change;
  31
  32     RemoteChange();
  33     RemoteChange(int64 changestamp,
  34                  const std::string& resource_id,
  35                  const std::string& md5_checksum,
  36                  const base::Time& updated_time,
  37                  const fileapi::FileSystemURL& url,
  38                  const FileChange& change);
  39     ~RemoteChange();
  40   };
  41
  42   struct RemoteChangeComparator {
  43     bool operator()(const RemoteChange& left, const RemoteChange& right);
  44   };
  45
  46   RemoteChangeHandler();
  47   virtual ~RemoteChangeHandler();
  48
  49   // Pushes the next change into |remote_change| and returns true.
  50   bool GetChange(RemoteChange* remote_change);
  51
  52   // Pushes the change for the |url| into |remote_change| and returns true.
  53   bool GetChangeForURL(const fileapi::FileSystemURL& url,
  54                        RemoteChange* remote_change);
  55
  56   // Appends |remote_change| into the change queue. |remote_change| overrides an
  57   // existing change for the same URL if exists.
  58   void AppendChange(const RemoteChange& remote_change);
  59
  60   // Removes a change for the |url|.
  61   bool RemoveChangeForURL(const fileapi::FileSystemURL& url);
  62
  63   // Removes changes for the |origin|.
  64   void RemoveChangesForOrigin(const GURL& origin);
  65
  66   bool HasChangesForOrigin(const GURL& origin) const;
  67   bool HasChanges() const { return !changes_.empty(); }
  68   size_t ChangesSize() const { return changes_.size(); }
  69
  70  private:
  71   struct ChangeQueueItem {
  72     int64 changestamp;
  73     fileapi::FileSystemURL url;
  74
  75     ChangeQueueItem();
  76     ChangeQueueItem(int64 changestamp,
  77                     const fileapi::FileSystemURL& url);
  78   };
  79
  80   struct ChangeQueueComparator {
  81     bool operator()(const ChangeQueueItem& left, const ChangeQueueItem& right);
  82   };
  83
  84   typedef std::set<ChangeQueueItem, ChangeQueueComparator> PendingChangeQueue;
  85
  86   struct ChangeMapItem {
  87     RemoteChange remote_change;
  88     PendingChangeQueue::iterator position_in_queue;
  89
  90     ChangeMapItem();
  91     ChangeMapItem(const RemoteChange& remote_change,
  92                   PendingChangeQueue::iterator position_in_queue);
  93     ~ChangeMapItem();
  94   };
  95
  96   // TODO(tzik): Consider using std::pair<base::FilePath, FileType> as the key
  97   // below to support directories and custom conflict handling.
  98   typedef std::map<base::FilePath::StringType, ChangeMapItem> PathToChangeMap;
  99   typedef std::map<GURL, PathToChangeMap> OriginToChangesMap;
 100
 101   PendingChangeQueue changes_;
 102   OriginToChangesMap origin_to_changes_map_;
 103
 104   DISALLOW_COPY_AND_ASSIGN(RemoteChangeHandler);
 105 };
 106
 107 }  // namespace sync_file_system
 108
 109 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_DRIVE_BACKEND_REMOTE_CHANGE_HANDLER_H_