PVer4: V4Database: Return stores that have a hash prefix for a given full hash

components/safe_browsing_db/v4_database.cc

 // Copyright 2016 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.
 
 #include <memory>
 
 #include "base/callback.h"
 #include "base/debug/leak_annotations.h"
 #include "base/files/file_util.h"
 #include "base/memory/ptr_util.h"
@@ skipping 150 matching lines @@
 
 std::unique_ptr<StoreStateMap> V4Database::GetStoreStateMap() {
   std::unique_ptr<StoreStateMap> store_state_map =
       base::MakeUnique<StoreStateMap>();
   for (const auto& store_map_iter : *store_map_) {
     (*store_state_map)[store_map_iter.first] = store_map_iter.second->state();
   }
   return store_state_map;
 }
 
+void V4Database::GetStoresMatchingFullHash(const FullHash& full_hash,

[Nathan Parker, 2016/07/19 23:05:56]

What's the usecase for this function?  I think the caller should specify which
stores it's interested in, since we don't want to check against stores that
aren't relevant (whitelists, etc).

[vakh (use Gerrit instead), 2016/07/20 00:07:43]

Done.

The goal of this method is to identify the stores that match a given full hash,
and then return the matching hash prefix.
I've updated the method to accept the list of stores to look at.

+                                           StoresMatched* stores_matched) {
+  DCHECK(stores_matched);
+  for (const auto& store_pair : *store_map_) {
+    const UpdateListIdentifier& identifier = store_pair.first;
+    const std::unique_ptr<V4Store>& store = store_pair.second;
+
+    HashPrefix hash_prefix = store->GetMatchingHashPrefix(full_hash);
+    if (!hash_prefix.empty()) {
+      stores_matched->push_back(identifier);
+    }
+  }
+}
+
 }  // namespace safe_browsing