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diff --git a/brillo/map_utils.h b/brillo/map_utils.h
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+++ b/brillo/map_utils.h
@@ -0,0 +1,71 @@
+// Copyright 2014 The Chromium OS 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 LIBCHROMEOS_BRILLO_MAP_UTILS_H_
+#define LIBCHROMEOS_BRILLO_MAP_UTILS_H_
+
+#include <map>
+#include <set>
+#include <utility>
+#include <vector>
+
+namespace brillo {
+
+// Given an STL map, returns a set containing all keys from the map.
+template<typename T>
+inline std::set<typename T::key_type> GetMapKeys(const T& map) {
+  std::set<typename T::key_type> keys;
+  for (const auto& pair : map)
+    keys.insert(keys.end(), pair.first);  // Map keys are already sorted.
+  return keys;
+}
+
+// Given an STL map, returns a vector containing all keys from the map.
+// The keys in the vector are sorted.
+template<typename T>
+inline std::vector<typename T::key_type> GetMapKeysAsVector(const T& map) {
+  std::vector<typename T::key_type> keys;
+  keys.reserve(map.size());
+  for (const auto& pair : map)
+    keys.push_back(pair.first);
+  return keys;
+}
+
+// Given an STL map, returns a vector containing all values from the map.
+template<typename T>
+inline std::vector<typename T::mapped_type> GetMapValues(const T& map) {
+  std::vector<typename T::mapped_type> values;
+  values.reserve(map.size());
+  for (const auto& pair : map)
+    values.push_back(pair.second);
+  return values;
+}
+
+// Given an STL map, returns a vector of key-value pairs from the map.
+template<typename T>
+inline std::vector<std::pair<typename T::key_type, typename T::mapped_type>>
+MapToVector(const T& map) {
+  std::vector<std::pair<typename T::key_type, typename T::mapped_type>> vector;
+  vector.reserve(map.size());
+  for (const auto& pair : map)
+    vector.push_back(pair);
+  return vector;
+}
+
+// Given an STL map, returns the value associated with a given key or a default
+// value if the key is not present in the map.
+template<typename T>
+inline typename T::mapped_type GetOrDefault(
+    const T& map,
+    typename T::key_type key,
+    const typename T::mapped_type& def) {
+  typename T::const_iterator it = map.find(key);
+  if (it == map.end())
+    return def;
+  return it->second;
+}
+
+}  // namespace brillo
+
+#endif  // LIBCHROMEOS_BRILLO_MAP_UTILS_H_