MergeResult ThreeWayMerge::mergeKeySet (const KeySet & base, const KeySet & ours, const KeySet & theirs, const Key & mergeRoot) { Key ourkey = ours.head ().dup (); Key theirkey = theirs.head ().dup (); Key basekey = base.head ().dup (); MergeResult merged = mergeKeySet ( MergeTask (BaseMergeKeys (base, basekey), OurMergeKeys (ours, ourkey), TheirMergeKeys (theirs, theirkey), mergeRoot)); return merged; }
void MetaMergeStrategy::resolveConflict(const MergeTask& task, Key& conflictKey, MergeResult& result) { conflictKey.rewindMeta(); Key currentMeta; string baseLookup = rebasePath (conflictKey, task.mergeRoot, task.baseParent); string ourLookup = rebasePath (conflictKey, task.mergeRoot, task.ourParent); string theirLookup = rebasePath (conflictKey, task.mergeRoot, task.theirParent); Key baseKey = task.base.lookup(baseLookup); Key ourKey = task.ours.lookup(ourLookup); Key theirKey = task.theirs.lookup(theirLookup); Key root ("user/", KEY_END); KeySet baseMeta = getMetaKeys (baseKey); KeySet ourMeta = getMetaKeys (ourKey); KeySet theirMeta = getMetaKeys (theirKey); MergeTask metaTask(BaseMergeKeys (baseMeta, root), OurMergeKeys (ourMeta, root), TheirMergeKeys (theirMeta, root), root); MergeResult metaResult = innerMerger.mergeKeySet(metaTask); KeySet mergedMeta = metaResult.getMergedKeys(); Key current; mergedMeta.rewind(); while ((current = mergedMeta.next())) { string metaName = current.getName().substr(string("user/").length()); conflictKey.setMeta(metaName, current.getString()); } ConflictOperation ourOperation = getOurConflictOperation(conflictKey); ConflictOperation theirOperation = getTheirConflictOperation(conflictKey); if (!metaResult.hasConflicts ()) { if (ourOperation == CONFLICT_META && theirOperation == CONFLICT_META) { // TODO: addConflict deletes the key content // without this strategy restoring the value the value would be lost // this happens only for CONFLICT_META <--> CONFLICT_META conflicts // add a test for this behaviour copyKeyValue(ourKey, conflictKey); result.resolveConflict (conflictKey); result.addMergeKey (conflictKey); } } }
int MergingKDB::synchronize (KeySet & returned, Key & parentKey, ThreeWayMerge & merger) { try { // write our config int ret = KDB::set (returned, parentKey); // update our config (if no conflict) KDB::get (returned, parentKey); return ret; } catch (KDBException const &) { // a conflict occurred, see if we can solve it with the merger // refresh the key database KeySet theirs = returned.dup (); KDB::get (theirs, parentKey); // try to merge MergeResult result = merger.mergeKeySet (MergeTask (BaseMergeKeys (base, parentKey), OurMergeKeys (returned, parentKey), TheirMergeKeys (theirs, parentKey), parentKey)); if (!result.hasConflicts ()) { // hurray, we solved the issue KeySet resultKeys = result.getMergedKeys (); int ret = KDB::set (resultKeys, parentKey); base = resultKeys; return ret; } else { // nothing we can do anymore KeySet conflictSet = result.getConflictSet (); throw MergingKDBException (parentKey, conflictSet); } } }
MergeTask reverse () const { return MergeTask (BaseMergeKeys (base, baseParent), OurMergeKeys (theirs, theirParent), TheirMergeKeys (ours, ourParent), mergeRoot); }