sync/engine/syncer.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 SYNC_ENGINE_SYNCER_H_
   6 #define SYNC_ENGINE_SYNCER_H_
   7
   8 #include <utility>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/gtest_prod_util.h"
  13 #include "base/synchronization/lock.h"
  14 #include "sync/engine/conflict_resolver.h"
  15 #include "sync/engine/syncer_types.h"
  16 #include "sync/internal_api/public/base/model_type.h"
  17 #include "sync/sessions/sync_session.h"
  18 #include "sync/util/extensions_activity_monitor.h"
  19
  20 namespace syncer {
  21
  22 namespace syncable {
  23 class Entry;
  24 class MutableEntry;
  25 }  // namespace syncable
  26
  27 enum SyncerStep {
  28   SYNCER_BEGIN,
  29   DOWNLOAD_UPDATES,
  30   VERIFY_UPDATES,
  31   PROCESS_UPDATES,
  32   STORE_TIMESTAMPS,
  33   APPLY_UPDATES,
  34   COMMIT,
  35   RESOLVE_CONFLICTS,
  36   APPLY_UPDATES_TO_RESOLVE_CONFLICTS,
  37   SYNCER_END
  38 };
  39
  40 // A Syncer provides a control interface for driving the individual steps
  41 // of the sync cycle.  Each cycle (hopefully) moves the client into closer
  42 // synchronization with the server.  The individual steps are modeled
  43 // as SyncerCommands, and the ordering of the steps is expressed using
  44 // the SyncerStep enum.
  45 //
  46 // A Syncer instance expects to run on a dedicated thread.  Calls
  47 // to SyncShare() may take an unbounded amount of time, as SyncerCommands
  48 // may block on network i/o, on lock contention, or on tasks posted to
  49 // other threads.
  50 class Syncer {
  51  public:
  52   typedef std::vector<int64> UnsyncedMetaHandles;
  53
  54   Syncer();
  55   virtual ~Syncer();
  56
  57   // Called by other threads to tell the syncer to stop what it's doing
  58   // and return early from SyncShare, if possible.
  59   bool ExitRequested();
  60   void RequestEarlyExit();
  61
  62   // Runs a sync cycle from |first_step| to |last_step|.
  63   virtual void SyncShare(sessions::SyncSession* session,
  64                          SyncerStep first_step,
  65                          SyncerStep last_step);
  66
  67  private:
  68   bool early_exit_requested_;
  69   base::Lock early_exit_requested_lock_;
  70
  71   ConflictResolver resolver_;
  72
  73   friend class SyncerTest;
  74   FRIEND_TEST_ALL_PREFIXES(SyncerTest, NameClashWithResolver);
  75   FRIEND_TEST_ALL_PREFIXES(SyncerTest, IllegalAndLegalUpdates);
  76   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingAndNewParent);
  77   FRIEND_TEST_ALL_PREFIXES(SyncerTest,
  78                            TestCommitListOrderingAndNewParentAndChild);
  79   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingCounterexample);
  80   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNesting);
  81   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNewItems);
  82   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestGetUnsyncedAndSimpleCommit);
  83   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnsynced);
  84   FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnapplied);
  85   FRIEND_TEST_ALL_PREFIXES(SyncerTest, UnappliedUpdateDuringCommit);
  86   FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryInFolder);
  87   FRIEND_TEST_ALL_PREFIXES(SyncerTest,
  88                            LongChangelistCreatesFakeOrphanedEntries);
  89   FRIEND_TEST_ALL_PREFIXES(SyncerTest, QuicklyMergeDualCreatedHierarchy);
  90   FRIEND_TEST_ALL_PREFIXES(SyncerTest, LongChangelistWithApplicationConflict);
  91   FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryWithLocalEdits);
  92   FRIEND_TEST_ALL_PREFIXES(EntryCreatedInNewFolderTest,
  93                            EntryCreatedInNewFolderMidSync);
  94
  95   DISALLOW_COPY_AND_ASSIGN(Syncer);
  96 };
  97
  98 // Utility function declarations.
  99 void CopyServerFields(syncable::Entry* src, syncable::MutableEntry* dest);
 100 void ClearServerData(syncable::MutableEntry* entry);
 101 const char* SyncerStepToString(const SyncerStep);
 102
 103 }  // namespace syncer
 104
 105 #endif  // SYNC_ENGINE_SYNCER_H_