2 * Copyright 2015 Facebook, Inc.
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef FOLLY_PORTABILITY_H_
18 #define FOLLY_PORTABILITY_H_
20 #ifndef FOLLY_NO_CONFIG
21 #include <folly/folly-config.h>
24 #ifdef FOLLY_PLATFORM_CONFIG
25 #include FOLLY_PLATFORM_CONFIG
28 #if FOLLY_HAVE_FEATURES_H
32 #include <folly/CPortability.h>
35 # include <malloc/malloc.h>
38 #if FOLLY_HAVE_SCHED_H
40 #ifndef FOLLY_HAVE_PTHREAD_YIELD
41 #define pthread_yield sched_yield
45 // A change in folly/MemoryMapping.cpp uses MAP_ANONYMOUS, which is named
46 // MAP_ANON on OSX/BSD.
47 #if defined(__APPLE__) || defined(__FreeBSD__)
51 #define MAP_ANONYMOUS MAP_ANON
56 // MaxAlign: max_align_t isn't supported by gcc
58 struct MaxAlign { char c; } __attribute__((__aligned__));
60 # error Cannot define MaxAlign on this platform
63 // compiler specific attribute translation
64 // msvc should come first, so if clang is in msvc mode it gets the right defines
66 // NOTE: this will only do checking in msvc with versions that support /analyze
68 # ifdef _USE_ATTRIBUTES_FOR_SAL
69 # undef _USE_ATTRIBUTES_FOR_SAL
72 # define _USE_ATTRIBUTES_FOR_SAL 1
74 # define FOLLY_PRINTF_FORMAT _Printf_format_string_
75 # define FOLLY_PRINTF_FORMAT_ATTR(format_param, dots_param) /**/
77 # define FOLLY_PRINTF_FORMAT /**/
78 # define FOLLY_PRINTF_FORMAT_ATTR(format_param, dots_param) \
79 __attribute__((__format__(__printf__, format_param, dots_param)))
83 #if defined(__clang__) || defined(__GNUC__)
84 # define FOLLY_DEPRECATED(msg) __attribute__((__deprecated__(msg)))
86 # define FOLLY_DEPRECATED
91 # define FOLLY_NORETURN __declspec(noreturn)
92 #elif defined(__clang__) || defined(__GNUC__)
93 # define FOLLY_NORETURN __attribute__((__noreturn__))
95 # define FOLLY_NORETURN
100 # define FOLLY_NOINLINE __declspec(noinline)
101 #elif defined(__clang__) || defined(__GNUC__)
102 # define FOLLY_NOINLINE __attribute__((__noinline__))
104 # define FOLLY_NOINLINE
109 # define FOLLY_ALWAYS_INLINE __forceinline
110 #elif defined(__clang__) || defined(__GNUC__)
111 # define FOLLY_ALWAYS_INLINE inline __attribute__((__always_inline__))
113 # define FOLLY_ALWAYS_INLINE
116 // detection for 64 bit
117 #if defined(__x86_64__) || defined(_M_X64)
123 // packing is very ugly in msvc
125 # define FOLLY_PACK_ATTR /**/
126 # define FOLLY_PACK_PUSH __pragma(pack(push, 1))
127 # define FOLLY_PACK_POP __pragma(pack(pop))
128 #elif defined(__clang__) || defined(__GNUC__)
129 # define FOLLY_PACK_ATTR __attribute__((__packed__))
130 # define FOLLY_PACK_PUSH /**/
131 # define FOLLY_PACK_POP /**/
133 # define FOLLY_PACK_ATTR /**/
134 # define FOLLY_PACK_PUSH /**/
135 # define FOLLY_PACK_POP /**/
138 // portable version check
139 #ifndef __GNUC_PREREQ
140 # if defined __GNUC__ && defined __GNUC_MINOR__
142 # define __GNUC_PREREQ(maj, min) ((__GNUC__ << 16) + __GNUC_MINOR__ >= \
143 ((maj) << 16) + (min))
146 # define __GNUC_PREREQ(maj, min) 0
151 /* Define macro wrappers for C++11's "final" and "override" keywords, which
152 * are supported in gcc 4.7 but not gcc 4.6. */
153 #if !defined(FOLLY_FINAL) && !defined(FOLLY_OVERRIDE)
154 # if defined(__clang__) || __GNUC_PREREQ(4, 7)
155 # define FOLLY_FINAL final
156 # define FOLLY_OVERRIDE override
158 # define FOLLY_FINAL /**/
159 # define FOLLY_OVERRIDE /**/
163 /* Platform specific TLS support
164 * gcc implements __thread
165 * msvc implements __declspec(thread)
166 * the semantics are the same
167 * (but remember __thread has different semantics when using emutls (ex. apple))
169 #if defined(_MSC_VER)
170 # define FOLLY_TLS __declspec(thread)
171 #elif defined(__GNUC__) || defined(__clang__)
172 # define FOLLY_TLS __thread
174 # error cannot define platform specific thread local storage
177 // Define to 1 if you have the `preadv' and `pwritev' functions, respectively
178 #if !defined(FOLLY_HAVE_PREADV) && !defined(FOLLY_HAVE_PWRITEV)
179 # if defined(__GLIBC_PREREQ)
180 # if __GLIBC_PREREQ(2, 10)
181 # define FOLLY_HAVE_PREADV 1
182 # define FOLLY_HAVE_PWRITEV 1
187 // It turns out that GNU libstdc++ and LLVM libc++ differ on how they implement
188 // the 'std' namespace; the latter uses inline namepsaces. Wrap this decision
189 // up in a macro to make forward-declarations easier.
192 #define FOLLY_NAMESPACE_STD_BEGIN _LIBCPP_BEGIN_NAMESPACE_STD
193 #define FOLLY_NAMESPACE_STD_END _LIBCPP_END_NAMESPACE_STD
195 #define FOLLY_NAMESPACE_STD_BEGIN namespace std {
196 #define FOLLY_NAMESPACE_STD_END }
199 // Some platforms lack clock_gettime(2) and clock_getres(2). Inject our own
200 // versions of these into the global namespace.
201 #if FOLLY_HAVE_CLOCK_GETTIME
204 #include <folly/detail/Clock.h>
207 // Provide our own std::__throw_* wrappers for platforms that don't have them
208 #if FOLLY_HAVE_BITS_FUNCTEXCEPT_H
209 #include <bits/functexcept.h>
211 #include <folly/detail/FunctionalExcept.h>
214 #if defined(__cplusplus)
215 // Unfortunately, boost::has_trivial_copy<T> is broken in libc++ due to its
216 // usage of __has_trivial_copy(), so we can't use it as a
217 // least-common-denominator for C++11 implementations that don't support
218 // std::is_trivially_copyable<T>.
220 // http://stackoverflow.com/questions/12754886/has-trivial-copy-behaves-differently-in-clang-and-gcc-whos-right
222 // As a result, use std::is_trivially_copyable() where it exists, and fall back
223 // to Boost otherwise.
224 #if FOLLY_HAVE_STD__IS_TRIVIALLY_COPYABLE
225 #include <type_traits>
226 #define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
227 (std::is_trivially_copyable<T>::value)
229 #include <boost/type_traits.hpp>
230 #define FOLLY_IS_TRIVIALLY_COPYABLE(T) \
231 (boost::has_trivial_copy<T>::value && \
232 boost::has_trivial_destructor<T>::value)
234 #endif // __cplusplus
236 // MSVC specific defines
237 // mainly for posix compat
240 // this definition is in a really silly place with a silly name
241 // and ifdefing it every time we want it is painful
243 typedef SSIZE_T ssize_t;
245 // sprintf semantics are not exactly identical
246 // but current usage is not a problem
247 # define snprintf _snprintf
249 // semantics here are identical
250 # define strerror_r(errno,buf,len) strerror_s(buf,len,errno)
252 // compiler specific to compiler specific
254 # define __PRETTY_FUNCTION__ __FUNCSIG__
257 #if FOLLY_UNUSUAL_GFLAGS_NAMESPACE
258 namespace FOLLY_GFLAGS_NAMESPACE { }
260 using namespace FOLLY_GFLAGS_NAMESPACE;
261 } // namespace gflags
264 // for TARGET_OS_IPHONE
266 #include <TargetConditionals.h>
269 // MacOS doesn't have malloc_usable_size()
270 #if defined(__APPLE__) && !defined(FOLLY_HAVE_MALLOC_USABLE_SIZE)
271 inline size_t malloc_usable_size(void* ptr) {
272 return malloc_size(ptr);
276 // RTTI may not be enabled for this compilation unit.
277 #if defined(__GXX_RTTI) || defined(__cpp_rtti)
278 # define FOLLY_HAS_RTTI 1
281 #endif // FOLLY_PORTABILITY_H_