1 /* Copyright (C) 1991-2012 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 /* Always use ISO C things. */ 133 #define __USE_ANSI 1 134 135 /* Convenience macros to test the versions of glibc and gcc. 136 Use them like this: 137 #if __GNUC_PREREQ (2,8) 138 ... code requiring gcc 2.8 or later ... 139 #endif 140 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 141 were not defined then. */ 142 #if defined __GNUC__ && defined __GNUC_MINOR__ 143 # define __GNUC_PREREQ(maj, min) \ 144 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 145 #else 146 # define __GNUC_PREREQ(maj, min) 0 147 #endif 148 149 150 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 151 #if defined _BSD_SOURCE && \ 152 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 153 defined _XOPEN_SOURCE || defined _GNU_SOURCE || defined _SVID_SOURCE) 154 # define __FAVOR_BSD 1 155 #endif 156 157 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 158 #ifdef _GNU_SOURCE 159 # undef _ISOC95_SOURCE 160 # define _ISOC95_SOURCE 1 161 # undef _ISOC99_SOURCE 162 # define _ISOC99_SOURCE 1 163 # undef _ISOC11_SOURCE 164 # define _ISOC11_SOURCE 1 165 # undef _POSIX_SOURCE 166 # define _POSIX_SOURCE 1 167 # undef _POSIX_C_SOURCE 168 # define _POSIX_C_SOURCE 200809L 169 # undef _XOPEN_SOURCE 170 # define _XOPEN_SOURCE 700 171 # undef _XOPEN_SOURCE_EXTENDED 172 # define _XOPEN_SOURCE_EXTENDED 1 173 # undef _LARGEFILE64_SOURCE 174 # define _LARGEFILE64_SOURCE 1 175 # undef _BSD_SOURCE 176 # define _BSD_SOURCE 1 177 # undef _SVID_SOURCE 178 # define _SVID_SOURCE 1 179 # undef _ATFILE_SOURCE 180 # define _ATFILE_SOURCE 1 181 #endif 182 183 /* If nothing (other than _GNU_SOURCE) is defined, 184 define _BSD_SOURCE and _SVID_SOURCE. */ 185 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 186 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 187 !defined _XOPEN_SOURCE && !defined _BSD_SOURCE && !defined _SVID_SOURCE) 188 # define _BSD_SOURCE 1 189 # define _SVID_SOURCE 1 190 #endif 191 192 /* This is to enable the ISO C11 extension. */ 193 #if (defined _ISOC11_SOURCE \ 194 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)) 195 # define __USE_ISOC11 1 196 #endif 197 198 /* This is to enable the ISO C99 extension. */ 199 #if (defined _ISOC99_SOURCE || defined _ISOC11_SOURCE \ 200 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 201 # define __USE_ISOC99 1 202 #endif 203 204 /* This is to enable the ISO C90 Amendment 1:1995 extension. */ 205 #if (defined _ISOC99_SOURCE || defined _ISOC11_SOURCE \ 206 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 207 # define __USE_ISOC95 1 208 #endif 209 210 /* This is to enable compatibility for ISO C++11. 211 212 So far g++ does not provide a macro. Check the temporary macro for 213 now, too. */ 214 #if ((defined __cplusplus && __cplusplus >= 201103L) \ 215 || defined __GXX_EXPERIMENTAL_CXX0X__) 216 # define __USE_ISOCXX11 1 217 #endif 218 219 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 220 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 221 #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 222 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 223 # define _POSIX_SOURCE 1 224 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 225 # define _POSIX_C_SOURCE 2 226 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 227 # define _POSIX_C_SOURCE 199506L 228 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 229 # define _POSIX_C_SOURCE 200112L 230 # else 231 # define _POSIX_C_SOURCE 200809L 232 # endif 233 # define __USE_POSIX_IMPLICITLY 1 234 #endif 235 236 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 237 # define __USE_POSIX 1 238 #endif 239 240 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 241 # define __USE_POSIX2 1 242 #endif 243 244 #if (_POSIX_C_SOURCE - 0) >= 199309L 245 # define __USE_POSIX199309 1 246 #endif 247 248 #if (_POSIX_C_SOURCE - 0) >= 199506L 249 # define __USE_POSIX199506 1 250 #endif 251 252 #if (_POSIX_C_SOURCE - 0) >= 200112L 253 # define __USE_XOPEN2K 1 254 # undef __USE_ISOC95 255 # define __USE_ISOC95 1 256 # undef __USE_ISOC99 257 # define __USE_ISOC99 1 258 #endif 259 260 #if (_POSIX_C_SOURCE - 0) >= 200809L 261 # define __USE_XOPEN2K8 1 262 # undef _ATFILE_SOURCE 263 # define _ATFILE_SOURCE 1 264 #endif 265 266 #ifdef _XOPEN_SOURCE 267 # define __USE_XOPEN 1 268 # if (_XOPEN_SOURCE - 0) >= 500 269 # define __USE_XOPEN_EXTENDED 1 270 # define __USE_UNIX98 1 271 # undef _LARGEFILE_SOURCE 272 # define _LARGEFILE_SOURCE 1 273 # if (_XOPEN_SOURCE - 0) >= 600 274 # if (_XOPEN_SOURCE - 0) >= 700 275 # define __USE_XOPEN2K8 1 276 # define __USE_XOPEN2K8XSI 1 277 # endif 278 # define __USE_XOPEN2K 1 279 # define __USE_XOPEN2KXSI 1 280 # undef __USE_ISOC95 281 # define __USE_ISOC95 1 282 # undef __USE_ISOC99 283 # define __USE_ISOC99 1 284 # endif 285 # else 286 # ifdef _XOPEN_SOURCE_EXTENDED 287 # define __USE_XOPEN_EXTENDED 1 288 # endif 289 # endif 290 #endif 291 292 #ifdef _LARGEFILE_SOURCE 293 # define __USE_LARGEFILE 1 294 #endif 295 296 #ifdef _LARGEFILE64_SOURCE 297 # define __USE_LARGEFILE64 1 298 #endif 299 300 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 301 # define __USE_FILE_OFFSET64 1 302 #endif 303 304 #if defined _BSD_SOURCE || defined _SVID_SOURCE 305 # define __USE_MISC 1 306 #endif 307 308 #ifdef _BSD_SOURCE 309 # define __USE_BSD 1 310 #endif 311 312 #ifdef _SVID_SOURCE 313 # define __USE_SVID 1 314 #endif 315 316 #ifdef _ATFILE_SOURCE 317 # define __USE_ATFILE 1 318 #endif 319 320 #ifdef _GNU_SOURCE 321 # define __USE_GNU 1 322 #endif 323 324 #if defined _REENTRANT || defined _THREAD_SAFE 325 # define __USE_REENTRANT 1 326 #endif 327 328 #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 329 && __GNUC_PREREQ (4, 1) && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 330 # if _FORTIFY_SOURCE > 1 331 # define __USE_FORTIFY_LEVEL 2 332 # else 333 # define __USE_FORTIFY_LEVEL 1 334 # endif 335 #else 336 # define __USE_FORTIFY_LEVEL 0 337 #endif 338 339 /* Get definitions of __STDC_* predefined macros, if the compiler has 340 not preincluded this header automatically. */ 341 #include <stdc-predef.h> 342 343 /* This macro indicates that the installed library is the GNU C Library. 344 For historic reasons the value now is 6 and this will stay from now 345 on. The use of this variable is deprecated. Use __GLIBC__ and 346 __GLIBC_MINOR__ now (see below) when you want to test for a specific 347 GNU C library version and use the values in <gnu/lib-names.h> to get 348 the sonames of the shared libraries. */ 349 #undef __GNU_LIBRARY__ 350 #define __GNU_LIBRARY__ 6 351 352 /* Major and minor version number of the GNU C library package. Use 353 these macros to test for features in specific releases. */ 354 #define __GLIBC__ 2 355 #define __GLIBC_MINOR__ 17 356 357 #define __GLIBC_PREREQ(maj, min) \ 358 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 359 360 /* Decide whether a compiler supports the long long datatypes. */ 361 #if defined __GNUC__ \ 362 || (defined __PGI && defined __i386__ ) \ 363 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 364 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 365 # define __GLIBC_HAVE_LONG_LONG 1 366 #endif 367 368 /* This is here only because every header file already includes this one. */ 369 #ifndef __ASSEMBLER__ 370 # ifndef _SYS_CDEFS_H 371 # include <sys/cdefs.h> 372 # endif 373 374 /* If we don't have __REDIRECT, prototypes will be missing if 375 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 376 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 377 # define __USE_LARGEFILE 1 378 # define __USE_LARGEFILE64 1 379 # endif 380 381 #endif /* !ASSEMBLER */ 382 383 /* Decide whether we can define 'extern inline' functions in headers. */ 384 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 385 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 386 && defined __extern_inline 387 # define __USE_EXTERN_INLINES 1 388 #endif 389 390 391 /* This is here only because every header file already includes this one. 392 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 393 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 394 that will always return failure (and set errno to ENOSYS). */ 395 #include <gnu/stubs.h> 396 397 398 #endif /* features.h */ 399