Allow admins to disable magic ref check on upload

Some sites manage to run their repositories in a way that prevents
users from ever being able to create refs/for, refs/drafts or
refs/publish names in a repository. Allow admins on those servers
to disable this (somewhat) expensive check before every upload.

Change-Id: Ibf51f9fa214aa07ec7bae9c40d6ef8ce6265e816

gerrit-server/src/main/java/com/google/gerrit/server/git/ReceiveConfig.java

@@ -0,0 +1,37 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.git;
+
+import com.google.gerrit.server.config.GerritServerConfig;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+
+import org.eclipse.jgit.lib.Config;
+
+@Singleton
+class ReceiveConfig {
+  final boolean checkMagicRefs;
+  final boolean checkReferencedObjectsAreReachable;
+
+  @Inject
+  ReceiveConfig(@GerritServerConfig Config config) {
+    checkMagicRefs = config.getBoolean(
+        "receive", null, "checkMagicRefs",
+        true);
+    checkReferencedObjectsAreReachable = config.getBoolean(
+        "receive", null, "checkReferencedObjectsAreReachable",
+        true);
+  }
+}