1 | /* Copyright (C) 1991-2013 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <http://www.gnu.org/licenses/>. */ |
17 | |
18 | #ifndef _FEATURES_H |
19 | #define _FEATURES_H 1 |
20 | |
21 | /* These are defined by the user (or the compiler) |
22 | to specify the desired environment: |
23 | |
24 | __STRICT_ANSI__ ISO Standard C. |
25 | _ISOC99_SOURCE Extensions to ISO C89 from ISO C99. |
26 | _ISOC11_SOURCE Extensions to ISO C99 from ISO C11. |
27 | _POSIX_SOURCE IEEE Std 1003.1. |
28 | _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2; |
29 | if >=199309L, add IEEE Std 1003.1b-1993; |
30 | if >=199506L, add IEEE Std 1003.1c-1995; |
31 | if >=200112L, all of IEEE 1003.1-2004 |
32 | if >=200809L, all of IEEE 1003.1-2008 |
33 | _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if |
34 | Single Unix conformance is wanted, to 600 for the |
35 | sixth revision, to 700 for the seventh revision. |
36 | _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions. |
37 | _LARGEFILE_SOURCE Some more functions for correct standard I/O. |
38 | _LARGEFILE64_SOURCE Additional functionality from LFS for large files. |
39 | _FILE_OFFSET_BITS=N Select default filesystem interface. |
40 | _BSD_SOURCE ISO C, POSIX, and 4.3BSD things. |
41 | _SVID_SOURCE ISO C, POSIX, and SVID things. |
42 | _ATFILE_SOURCE Additional *at interfaces. |
43 | _GNU_SOURCE All of the above, plus GNU extensions. |
44 | _REENTRANT Select additionally reentrant object. |
45 | _THREAD_SAFE Same as _REENTRANT, often used by other systems. |
46 | _FORTIFY_SOURCE If set to numeric value > 0 additional security |
47 | measures are defined, according to level. |
48 | |
49 | The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__. |
50 | If none of these are defined, the default is to have _SVID_SOURCE, |
51 | _BSD_SOURCE, and _POSIX_SOURCE set to one and _POSIX_C_SOURCE set to |
52 | 200112L. If more than one of these are defined, they accumulate. |
53 | For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE |
54 | together give you ISO C, 1003.1, and 1003.2, but nothing else. |
55 | |
56 | These are defined by this file and are used by the |
57 | header files to decide what to declare or define: |
58 | |
59 | __USE_ISOC11 Define ISO C11 things. |
60 | __USE_ISOC99 Define ISO C99 things. |
61 | __USE_ISOC95 Define ISO C90 AMD1 (C95) things. |
62 | __USE_POSIX Define IEEE Std 1003.1 things. |
63 | __USE_POSIX2 Define IEEE Std 1003.2 things. |
64 | __USE_POSIX199309 Define IEEE Std 1003.1, and .1b things. |
65 | __USE_POSIX199506 Define IEEE Std 1003.1, .1b, .1c and .1i things. |
66 | __USE_XOPEN Define XPG things. |
67 | __USE_XOPEN_EXTENDED Define X/Open Unix things. |
68 | __USE_UNIX98 Define Single Unix V2 things. |
69 | __USE_XOPEN2K Define XPG6 things. |
70 | __USE_XOPEN2KXSI Define XPG6 XSI things. |
71 | __USE_XOPEN2K8 Define XPG7 things. |
72 | __USE_XOPEN2K8XSI Define XPG7 XSI things. |
73 | __USE_LARGEFILE Define correct standard I/O things. |
74 | __USE_LARGEFILE64 Define LFS things with separate names. |
75 | __USE_FILE_OFFSET64 Define 64bit interface as default. |
76 | __USE_BSD Define 4.3BSD things. |
77 | __USE_SVID Define SVID things. |
78 | __USE_MISC Define things common to BSD and System V Unix. |
79 | __USE_ATFILE Define *at interfaces and AT_* constants for them. |
80 | __USE_GNU Define GNU extensions. |
81 | __USE_REENTRANT Define reentrant/thread-safe *_r functions. |
82 | __USE_FORTIFY_LEVEL Additional security measures used, according to level. |
83 | __FAVOR_BSD Favor 4.3BSD things in cases of conflict. |
84 | |
85 | The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are |
86 | defined by this file unconditionally. `__GNU_LIBRARY__' is provided |
87 | only for compatibility. All new code should use the other symbols |
88 | to test for features. |
89 | |
90 | All macros listed above as possibly being defined by this file are |
91 | explicitly undefined if they are not explicitly defined. |
92 | Feature-test macros that are not defined by the user or compiler |
93 | but are implied by the other feature-test macros defined (or by the |
94 | lack of any definitions) are defined by the file. */ |
95 | |
96 | |
97 | /* Undefine everything, so we get a clean slate. */ |
98 | #undef __USE_ISOC11 |
99 | #undef __USE_ISOC99 |
100 | #undef __USE_ISOC95 |
101 | #undef __USE_ISOCXX11 |
102 | #undef __USE_POSIX |
103 | #undef __USE_POSIX2 |
104 | #undef __USE_POSIX199309 |
105 | #undef __USE_POSIX199506 |
106 | #undef __USE_XOPEN |
107 | #undef __USE_XOPEN_EXTENDED |
108 | #undef __USE_UNIX98 |
109 | #undef __USE_XOPEN2K |
110 | #undef __USE_XOPEN2KXSI |
111 | #undef __USE_XOPEN2K8 |
112 | #undef __USE_XOPEN2K8XSI |
113 | #undef __USE_LARGEFILE |
114 | #undef __USE_LARGEFILE64 |
115 | #undef __USE_FILE_OFFSET64 |
116 | #undef __USE_BSD |
117 | #undef __USE_SVID |
118 | #undef __USE_MISC |
119 | #undef __USE_ATFILE |
120 | #undef __USE_GNU |
121 | #undef __USE_REENTRANT |
122 | #undef __USE_FORTIFY_LEVEL |
123 | #undef __FAVOR_BSD |
124 | #undef __KERNEL_STRICT_NAMES |
125 | |
126 | /* Suppress kernel-name space pollution unless user expressedly asks |
127 | for it. */ |
128 | #ifndef _LOOSE_KERNEL_NAMES |
129 | # define __KERNEL_STRICT_NAMES |
130 | #endif |
131 | |
132 | /* Convenience macros to test the versions of glibc and gcc. |
133 | Use them like this: |
134 | #if __GNUC_PREREQ (2,8) |
135 | ... code requiring gcc 2.8 or later ... |
136 | #endif |
137 | Note - they won't work for gcc1 or glibc1, since the _MINOR macros |
138 | were not defined then. */ |
139 | #if defined __GNUC__ && defined __GNUC_MINOR__ |
140 | # define __GNUC_PREREQ(maj, min) \ |
141 | ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) |
142 | #else |
143 | # define __GNUC_PREREQ(maj, min) 0 |
144 | #endif |
145 | |
146 | |
147 | /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ |
148 | #if defined _BSD_SOURCE && \ |
149 | !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ |
150 | defined _XOPEN_SOURCE || defined _GNU_SOURCE || defined _SVID_SOURCE) |
151 | # define __FAVOR_BSD 1 |
152 | #endif |
153 | |
154 | /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ |
155 | #ifdef _GNU_SOURCE |
156 | # undef _ISOC95_SOURCE |
157 | # define _ISOC95_SOURCE 1 |
158 | # undef _ISOC99_SOURCE |
159 | # define _ISOC99_SOURCE 1 |
160 | # undef _ISOC11_SOURCE |
161 | # define _ISOC11_SOURCE 1 |
162 | # undef _POSIX_SOURCE |
163 | # define _POSIX_SOURCE 1 |
164 | # undef _POSIX_C_SOURCE |
165 | # define _POSIX_C_SOURCE 200809L |
166 | # undef _XOPEN_SOURCE |
167 | # define _XOPEN_SOURCE 700 |
168 | # undef _XOPEN_SOURCE_EXTENDED |
169 | # define _XOPEN_SOURCE_EXTENDED 1 |
170 | # undef _LARGEFILE64_SOURCE |
171 | # define _LARGEFILE64_SOURCE 1 |
172 | # undef _BSD_SOURCE |
173 | # define _BSD_SOURCE 1 |
174 | # undef _SVID_SOURCE |
175 | # define _SVID_SOURCE 1 |
176 | # undef _ATFILE_SOURCE |
177 | # define _ATFILE_SOURCE 1 |
178 | #endif |
179 | |
180 | /* If nothing (other than _GNU_SOURCE) is defined, |
181 | define _BSD_SOURCE and _SVID_SOURCE. */ |
182 | #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ |
183 | !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ |
184 | !defined _XOPEN_SOURCE && !defined _BSD_SOURCE && !defined _SVID_SOURCE) |
185 | # define _BSD_SOURCE 1 |
186 | # define _SVID_SOURCE 1 |
187 | #endif |
188 | |
189 | /* This is to enable the ISO C11 extension. */ |
190 | #if (defined _ISOC11_SOURCE \ |
191 | || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)) |
192 | # define __USE_ISOC11 1 |
193 | #endif |
194 | |
195 | /* This is to enable the ISO C99 extension. */ |
196 | #if (defined _ISOC99_SOURCE || defined _ISOC11_SOURCE \ |
197 | || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) |
198 | # define __USE_ISOC99 1 |
199 | #endif |
200 | |
201 | /* This is to enable the ISO C90 Amendment 1:1995 extension. */ |
202 | #if (defined _ISOC99_SOURCE || defined _ISOC11_SOURCE \ |
203 | || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) |
204 | # define __USE_ISOC95 1 |
205 | #endif |
206 | |
207 | /* This is to enable compatibility for ISO C++11. |
208 | |
209 | So far g++ does not provide a macro. Check the temporary macro for |
210 | now, too. */ |
211 | #if ((defined __cplusplus && __cplusplus >= 201103L) \ |
212 | || defined __GXX_EXPERIMENTAL_CXX0X__) |
213 | # define __USE_ISOCXX11 1 |
214 | #endif |
215 | |
216 | /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 |
217 | (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ |
218 | #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ |
219 | !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) |
220 | # define _POSIX_SOURCE 1 |
221 | # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 |
222 | # define _POSIX_C_SOURCE 2 |
223 | # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 |
224 | # define _POSIX_C_SOURCE 199506L |
225 | # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 |
226 | # define _POSIX_C_SOURCE 200112L |
227 | # else |
228 | # define _POSIX_C_SOURCE 200809L |
229 | # endif |
230 | # define __USE_POSIX_IMPLICITLY 1 |
231 | #endif |
232 | |
233 | #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE |
234 | # define __USE_POSIX 1 |
235 | #endif |
236 | |
237 | #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE |
238 | # define __USE_POSIX2 1 |
239 | #endif |
240 | |
241 | #if (_POSIX_C_SOURCE - 0) >= 199309L |
242 | # define __USE_POSIX199309 1 |
243 | #endif |
244 | |
245 | #if (_POSIX_C_SOURCE - 0) >= 199506L |
246 | # define __USE_POSIX199506 1 |
247 | #endif |
248 | |
249 | #if (_POSIX_C_SOURCE - 0) >= 200112L |
250 | # define __USE_XOPEN2K 1 |
251 | # undef __USE_ISOC95 |
252 | # define __USE_ISOC95 1 |
253 | # undef __USE_ISOC99 |
254 | # define __USE_ISOC99 1 |
255 | #endif |
256 | |
257 | #if (_POSIX_C_SOURCE - 0) >= 200809L |
258 | # define __USE_XOPEN2K8 1 |
259 | # undef _ATFILE_SOURCE |
260 | # define _ATFILE_SOURCE 1 |
261 | #endif |
262 | |
263 | #ifdef _XOPEN_SOURCE |
264 | # define __USE_XOPEN 1 |
265 | # if (_XOPEN_SOURCE - 0) >= 500 |
266 | # define __USE_XOPEN_EXTENDED 1 |
267 | # define __USE_UNIX98 1 |
268 | # undef _LARGEFILE_SOURCE |
269 | # define _LARGEFILE_SOURCE 1 |
270 | # if (_XOPEN_SOURCE - 0) >= 600 |
271 | # if (_XOPEN_SOURCE - 0) >= 700 |
272 | # define __USE_XOPEN2K8 1 |
273 | # define __USE_XOPEN2K8XSI 1 |
274 | # endif |
275 | # define __USE_XOPEN2K 1 |
276 | # define __USE_XOPEN2KXSI 1 |
277 | # undef __USE_ISOC95 |
278 | # define __USE_ISOC95 1 |
279 | # undef __USE_ISOC99 |
280 | # define __USE_ISOC99 1 |
281 | # endif |
282 | # else |
283 | # ifdef _XOPEN_SOURCE_EXTENDED |
284 | # define __USE_XOPEN_EXTENDED 1 |
285 | # endif |
286 | # endif |
287 | #endif |
288 | |
289 | #ifdef _LARGEFILE_SOURCE |
290 | # define __USE_LARGEFILE 1 |
291 | #endif |
292 | |
293 | #ifdef _LARGEFILE64_SOURCE |
294 | # define __USE_LARGEFILE64 1 |
295 | #endif |
296 | |
297 | #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 |
298 | # define __USE_FILE_OFFSET64 1 |
299 | #endif |
300 | |
301 | #if defined _BSD_SOURCE || defined _SVID_SOURCE |
302 | # define __USE_MISC 1 |
303 | #endif |
304 | |
305 | #ifdef _BSD_SOURCE |
306 | # define __USE_BSD 1 |
307 | #endif |
308 | |
309 | #ifdef _SVID_SOURCE |
310 | # define __USE_SVID 1 |
311 | #endif |
312 | |
313 | #ifdef _ATFILE_SOURCE |
314 | # define __USE_ATFILE 1 |
315 | #endif |
316 | |
317 | #ifdef _GNU_SOURCE |
318 | # define __USE_GNU 1 |
319 | #endif |
320 | |
321 | #if defined _REENTRANT || defined _THREAD_SAFE |
322 | # define __USE_REENTRANT 1 |
323 | #endif |
324 | |
325 | #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 |
326 | # if !defined __OPTIMIZE__ || __OPTIMIZE__ <= 0 |
327 | # warning _FORTIFY_SOURCE requires compiling with optimization (-O) |
328 | # elif !__GNUC_PREREQ (4, 1) |
329 | # warning _FORTIFY_SOURCE requires GCC 4.1 or later |
330 | # elif _FORTIFY_SOURCE > 1 |
331 | # define __USE_FORTIFY_LEVEL 2 |
332 | # else |
333 | # define __USE_FORTIFY_LEVEL 1 |
334 | # endif |
335 | #endif |
336 | #ifndef __USE_FORTIFY_LEVEL |
337 | # define __USE_FORTIFY_LEVEL 0 |
338 | #endif |
339 | |
340 | /* Get definitions of __STDC_* predefined macros, if the compiler has |
341 | not preincluded this header automatically. */ |
342 | #include <stdc-predef.h> |
343 | |
344 | /* This macro indicates that the installed library is the GNU C Library. |
345 | For historic reasons the value now is 6 and this will stay from now |
346 | on. The use of this variable is deprecated. Use __GLIBC__ and |
347 | __GLIBC_MINOR__ now (see below) when you want to test for a specific |
348 | GNU C library version and use the values in <gnu/lib-names.h> to get |
349 | the sonames of the shared libraries. */ |
350 | #undef __GNU_LIBRARY__ |
351 | #define __GNU_LIBRARY__ 6 |
352 | |
353 | /* Major and minor version number of the GNU C library package. Use |
354 | these macros to test for features in specific releases. */ |
355 | #define __GLIBC__ 2 |
356 | #define __GLIBC_MINOR__ 18 |
357 | |
358 | #define __GLIBC_PREREQ(maj, min) \ |
359 | ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) |
360 | |
361 | /* This is here only because every header file already includes this one. */ |
362 | #ifndef __ASSEMBLER__ |
363 | # ifndef _SYS_CDEFS_H |
364 | # include <sys/cdefs.h> |
365 | # endif |
366 | |
367 | /* If we don't have __REDIRECT, prototypes will be missing if |
368 | __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ |
369 | # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT |
370 | # define __USE_LARGEFILE 1 |
371 | # define __USE_LARGEFILE64 1 |
372 | # endif |
373 | |
374 | #endif /* !ASSEMBLER */ |
375 | |
376 | /* Decide whether we can define 'extern inline' functions in headers. */ |
377 | #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ |
378 | && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ |
379 | && defined __extern_inline |
380 | # define __USE_EXTERN_INLINES 1 |
381 | #endif |
382 | |
383 | |
384 | /* This is here only because every header file already includes this one. |
385 | Get the definitions of all the appropriate `__stub_FUNCTION' symbols. |
386 | <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub |
387 | that will always return failure (and set errno to ENOSYS). */ |
388 | #include <gnu/stubs.h> |
389 | |
390 | |
391 | #endif /* features.h */ |
392 | |