sync: Introduce ModelTypeRegistry and helpers

sync/engine/committer_list.h

Index: sync/engine/committer_list.h
diff --git a/sync/engine/committer_list.h b/sync/engine/committer_list.h
new file mode 100644
index 0000000000000000000000000000000000000000..4385b3744729c54b95fec6975551412ef0526c90
--- /dev/null
+++ b/sync/engine/committer_list.h
@@ -0,0 +1,62 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SYNC_ENGINE_COMMITTER_LIST_H_
+#define SYNC_ENGINE_COMMITTER_LIST_H_
+
+#include <map>
+#include <vector>
+
+#include "base/stl_util.h"
+#include "sync/base/sync_export.h"
+#include "sync/internal_api/public/base/model_type.h"
+#include "sync/internal_api/public/engine/model_safe_worker.h"
+
+namespace syncer {
+
+namespace syncable {
+class Directory;
+}  // namespace syncable
+
+class SyncDirectoryCommitContributor;
+class SyncDirectoryCommitContribution;
+
+// This class manages the set of per-type committer objects.
+//
+// It owns these types and hides the details of iterating over all of them.
+// Many methods allow the caller to specify a subset of types on which the
+// operation is to be applied.  It is a logic error if the supplied set of types
+// contains a type which was not previously registered.
+class SYNC_EXPORT_PRIVATE CommitterList {
+ public:
+  typedef std::map<ModelType, SyncDirectoryCommitContribution*> ContributionMap;
+
+  CommitterList();
+  ~CommitterList();
+
+  // Registers a commit contributor directly.
+  void RegisterType(
+      ModelType type,
+      SyncDirectoryCommitContributor* contributor);
+
+  // Gathers a set of contributions to be used to populate a commit message.
+  void GatherCommitContributions(
+      ModelTypeSet commit_types,
+      size_t max_entries,
+      ContributionMap* contributions);
+
+ private:
+  typedef std::map<ModelType, SyncDirectoryCommitContributor*>
+      CommitContributorMap;
+
+  // A map of 'commit contributors', one for each enabled type.
+  CommitContributorMap commit_contributor_map_;
+
+  // Deleter for the |commit_contributor_map_|.
+  STLValueDeleter<CommitContributorMap> commit_contributor_deleter_;

[Nicolas Zea, 2014/01/04 02:09:34]

disallow copy and assign

[rlarocque, 2014/01/06 20:03:33]

Done.

+};
+
+}  // namespace syncer
+
+#endif  // SYNC_ENGINE_COMMITTER_LIST_H_