1/*
2 * Copyright 2016-present Facebook, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#pragma once
18
19#include <folly/portability/Config.h>
20
21#if !FOLLY_HAVE_LIBGFLAGS
22// glog/logging.h is dependent on this implementation detail
23// being defined otherwise it undefines all of this -_-....
24//
25// Also, this is deliberately expanded such that places using
26// it directly break loudly. (C will break louder than C++, but oh well)
27#define DECLARE_VARIABLE() \
28 static_assert(false, "You shouldn't be using GFlags internals.");
29
30#define FOLLY_DECLARE_FLAG(_type, _shortType, _name) \
31 namespace fL##_shortType { \
32 extern _type FLAGS_##_name; \
33 } \
34 using fL##_shortType::FLAGS_##_name
35
36#define DECLARE_bool(_name) FOLLY_DECLARE_FLAG(bool, B, _name)
37#define DECLARE_double(_name) FOLLY_DECLARE_FLAG(double, D, _name)
38#define DECLARE_int32(_name) FOLLY_DECLARE_FLAG(int, I, _name)
39#define DECLARE_int64(_name) FOLLY_DECLARE_FLAG(long long, I64, _name)
40#define DECLARE_uint32(_name) FOLLY_DECLARE_FLAG(unsigned long, U32, _name)
41#define DECLARE_uint64(_name) FOLLY_DECLARE_FLAG(unsigned long long, U64, _name)
42#define DECLARE_string(_name) FOLLY_DECLARE_FLAG(std::string, S, _name)
43
44#define FOLLY_DEFINE_FLAG(_type, _shortType, _name, _default) \
45 namespace fL##_shortType { \
46 _type FLAGS_##_name = _default; \
47 } \
48 using fL##_shortType::FLAGS_##_name
49
50#define DEFINE_bool(_name, _default, _description) \
51 FOLLY_DEFINE_FLAG(bool, B, _name, _default)
52#define DEFINE_double(_name, _default, _description) \
53 FOLLY_DEFINE_FLAG(double, D, _name, _default)
54#define DEFINE_int32(_name, _default, _description) \
55 FOLLY_DEFINE_FLAG(int, I, _name, _default)
56#define DEFINE_int64(_name, _default, _description) \
57 FOLLY_DEFINE_FLAG(long long, I64, _name, _default)
58#define DEFINE_uint32(_name, _default, _description) \
59 FOLLY_DEFINE_FLAG(unsigned long, U32, _name, _default)
60#define DEFINE_uint64(_name, _default, _description) \
61 FOLLY_DEFINE_FLAG(unsigned long long, U64, _name, _default)
62#define DEFINE_string(_name, _default, _description) \
63 FOLLY_DEFINE_FLAG(std::string, S, _name, _default)
64
65namespace google {
66class FlagSaver {};
67} // namespace google
68
69#else
70#include <gflags/gflags.h>
71#endif
72