ceph/src/rocksdb/util/hash_containers.h

   1 //  Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5
   6 // This header establishes compile-time pluggable implementations of hashed
   7 // container structures, so that deployments have the option of minimal
   8 // dependencies with ok performance (e.g. std::unordered_map) or more
   9 // dependencies with optimized performance (e.g. folly::F14FastMap).
  10
  11 #pragma once
  12
  13 #include "rocksdb/rocksdb_namespace.h"
  14
  15 #ifdef USE_FOLLY
  16
  17 #include <folly/container/F14Map.h>
  18 #include <folly/container/F14Set.h>
  19
  20 namespace ROCKSDB_NAMESPACE {
  21
  22 template <typename K, typename V>
  23 using UnorderedMap = folly::F14FastMap<K, V>;
  24
  25 template <typename K, typename V, typename H>
  26 using UnorderedMapH = folly::F14FastMap<K, V, H>;
  27
  28 template <typename K>
  29 using UnorderedSet = folly::F14FastSet<K>;
  30
  31 }  // namespace ROCKSDB_NAMESPACE
  32
  33 #else
  34
  35 #include <unordered_map>
  36 #include <unordered_set>
  37
  38 namespace ROCKSDB_NAMESPACE {
  39
  40 template <typename K, typename V>
  41 using UnorderedMap = std::unordered_map<K, V>;
  42
  43 template <typename K, typename V, typename H>
  44 using UnorderedMapH = std::unordered_map<K, V, H>;
  45
  46 template <typename K>
  47 using UnorderedSet = std::unordered_set<K>;
  48
  49 }  // namespace ROCKSDB_NAMESPACE
  50
  51 #endif