sync/engine/conflict_util.cc

   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 #include "sync/engine/conflict_util.h"
   6
   7 #include "sync/syncable/mutable_entry.h"
   8
   9 namespace syncer {
  10
  11 using syncable::MutableEntry;
  12
  13 namespace conflict_util {
  14
  15 // Allow the server's changes to take precedence.
  16 // This will take effect during the next ApplyUpdates step.
  17 void IgnoreLocalChanges(MutableEntry* entry) {
  18   DCHECK(entry->GetIsUnsynced());
  19   DCHECK(entry->GetIsUnappliedUpdate());
  20   entry->PutIsUnsynced(false);
  21 }
  22
  23 // Overwrite the server with our own value.
  24 // We will commit our local data, overwriting the server, at the next
  25 // opportunity.
  26 void OverwriteServerChanges(MutableEntry* entry) {
  27   DCHECK(entry->GetIsUnsynced());
  28   DCHECK(entry->GetIsUnappliedUpdate());
  29   entry->PutBaseVersion(entry->GetServerVersion());
  30   entry->PutIsUnappliedUpdate(false);
  31 }
  32
  33 // Having determined that everything matches, we ignore the non-conflict.
  34 void IgnoreConflict(MutableEntry* entry) {
  35   // If we didn't also unset IS_UNAPPLIED_UPDATE, then we would lose unsynced
  36   // positional data from adjacent entries when the server update gets applied
  37   // and the item is re-inserted into the PREV_ID/NEXT_ID linked list. This is
  38   // primarily an issue because we commit after applying updates, and is most
  39   // commonly seen when positional changes are made while a passphrase is
  40   // required (and hence there will be many encryption conflicts).
  41   DCHECK(entry->GetIsUnsynced());
  42   DCHECK(entry->GetIsUnappliedUpdate());
  43   entry->PutBaseVersion(entry->GetServerVersion());
  44   entry->PutIsUnappliedUpdate(false);
  45   entry->PutIsUnsynced(false);
  46 }
  47
  48 }  // namespace conflict_util
  49 }  // namespace syncer