New policy protobuf protocol.

chrome/browser/policy/policy_map.h

+// Copyright (c) 2011 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 CHROME_BROWSER_POLICY_POLICY_MAP_H_
+#define CHROME_BROWSER_POLICY_POLICY_MAP_H_
+
+#include <map>
+
+#include "base/values.h"
+#include "policy/configuration_policy_type.h"
+
+namespace policy {
+
+// Wrapper class around a std::map<ConfigurationPolicyType, Value*> that
+// properly cleans up after itself when going out of scope.
+// Exposes interesting methods of the underlying std::map.
+class PolicyMap {
+ public:
+  typedef std::map<ConfigurationPolicyType, Value*> PolicyMapType;
+  typedef PolicyMapType::const_iterator const_iterator;
+
+  PolicyMap();
+  virtual ~PolicyMap();
+
+  // Returns a weak reference to the value currently stored for key |policy|.
+  // Ownership is retained by PolicyMap; callers should use Value::DeepCopy
+  // if they need a copy that they own themselves.
+  // Returns NULL if the map does not contain a value for |policy|.
+  const Value* Get(ConfigurationPolicyType policy) const;
+  // Takes ownership of |value|. Overwrites any existing value stored in the
+  // map for the key |policy|.
+  void Set(ConfigurationPolicyType policy, Value* value);
+  void Erase(ConfigurationPolicyType policy);
+
+  void Swap(PolicyMap* other);
+
+  bool Equals(const PolicyMap& other) const;
+  bool empty() const;
+  size_t size() const;
+
+  const_iterator begin() const;
+  const_iterator end() const;
+  void Clear();
+
+ private:
+  // Helper function for Equals(...).
+  static bool MapEntryEquals(const PolicyMapType::value_type& a,
+                             const PolicyMapType::value_type& b);
+
+  PolicyMapType map_;
+
+  DISALLOW_COPY_AND_ASSIGN(PolicyMap);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_POLICY_MAP_H_