1 /* Copyright (C) 1991-1993,1995-2007,2009,2010 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, write to the Free 16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 17 02111-1307 USA. */ 18 19 #ifndef _FEATURES_H 20 #define _FEATURES_H 1 21 22 /* These are defined by the user (or the compiler) 23 to specify the desired environment: 24 25 __STRICT_ANSI__ ISO Standard C. 26 _ISOC99_SOURCE Extensions to ISO C89 from ISO C99. 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_ISOC99 Define ISO C99 things. 60 __USE_ISOC95 Define ISO C90 AMD1 (C95) things. 61 __USE_POSIX Define IEEE Std 1003.1 things. 62 __USE_POSIX2 Define IEEE Std 1003.2 things. 63 __USE_POSIX199309 Define IEEE Std 1003.1, and .1b things. 64 __USE_POSIX199506 Define IEEE Std 1003.1, .1b, .1c and .1i things. 65 __USE_XOPEN Define XPG things. 66 __USE_XOPEN_EXTENDED Define X/Open Unix things. 67 __USE_UNIX98 Define Single Unix V2 things. 68 __USE_XOPEN2K Define XPG6 things. 69 __USE_XOPEN2KXSI Define XPG6 XSI things. 70 __USE_XOPEN2K8XSI Define XPG7 XSI things. 71 __USE_LARGEFILE Define correct standard I/O things. 72 __USE_LARGEFILE64 Define LFS things with separate names. 73 __USE_FILE_OFFSET64 Define 64bit interface as default. 74 __USE_BSD Define 4.3BSD things. 75 __USE_SVID Define SVID things. 76 __USE_MISC Define things common to BSD and System V Unix. 77 __USE_ATFILE Define *at interfaces and AT_* constants for them. 78 __USE_GNU Define GNU extensions. 79 __USE_REENTRANT Define reentrant/thread-safe *_r functions. 80 __USE_FORTIFY_LEVEL Additional security measures used, according to level. 81 __FAVOR_BSD Favor 4.3BSD things in cases of conflict. 82 83 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are 84 defined by this file unconditionally. `__GNU_LIBRARY__' is provided 85 only for compatibility. All new code should use the other symbols 86 to test for features. 87 88 All macros listed above as possibly being defined by this file are 89 explicitly undefined if they are not explicitly defined. 90 Feature-test macros that are not defined by the user or compiler 91 but are implied by the other feature-test macros defined (or by the 92 lack of any definitions) are defined by the file. */ 93 94 95 /* Undefine everything, so we get a clean slate. */ 96 #undef __USE_ISOC99 97 #undef __USE_ISOC95 98 #undef __USE_POSIX 99 #undef __USE_POSIX2 100 #undef __USE_POSIX199309 101 #undef __USE_POSIX199506 102 #undef __USE_XOPEN 103 #undef __USE_XOPEN_EXTENDED 104 #undef __USE_UNIX98 105 #undef __USE_XOPEN2K 106 #undef __USE_XOPEN2KXSI 107 #undef __USE_XOPEN2K8 108 #undef __USE_XOPEN2K8XSI 109 #undef __USE_LARGEFILE 110 #undef __USE_LARGEFILE64 111 #undef __USE_FILE_OFFSET64 112 #undef __USE_BSD 113 #undef __USE_SVID 114 #undef __USE_MISC 115 #undef __USE_ATFILE 116 #undef __USE_GNU 117 #undef __USE_REENTRANT 118 #undef __USE_FORTIFY_LEVEL 119 #undef __FAVOR_BSD 120 #undef __KERNEL_STRICT_NAMES 121 122 /* Suppress kernel-name space pollution unless user expressedly asks 123 for it. */ 124 #ifndef _LOOSE_KERNEL_NAMES 125 # define __KERNEL_STRICT_NAMES 126 #endif 127 128 /* Always use ISO C things. */ 129 #define __USE_ANSI 1 130 131 /* Convenience macros to test the versions of glibc and gcc. 132 Use them like this: 133 #if __GNUC_PREREQ (2,8) 134 ... code requiring gcc 2.8 or later ... 135 #endif 136 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 137 were not defined then. */ 138 #if defined __GNUC__ && defined __GNUC_MINOR__ 139 # define __GNUC_PREREQ(maj, min) \ 140 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 141 #else 142 # define __GNUC_PREREQ(maj, min) 0 143 #endif 144 145 146 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 147 #if defined _BSD_SOURCE && \ 148 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 149 defined _XOPEN_SOURCE || defined _GNU_SOURCE || defined _SVID_SOURCE) 150 # define __FAVOR_BSD 1 151 #endif 152 153 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 154 #ifdef _GNU_SOURCE 155 # undef _ISOC95_SOURCE 156 # define _ISOC95_SOURCE 1 157 # undef _ISOC99_SOURCE 158 # define _ISOC99_SOURCE 1 159 # undef _POSIX_SOURCE 160 # define _POSIX_SOURCE 1 161 # undef _POSIX_C_SOURCE 162 # define _POSIX_C_SOURCE 200809L 163 # undef _XOPEN_SOURCE 164 # define _XOPEN_SOURCE 700 165 # undef _XOPEN_SOURCE_EXTENDED 166 # define _XOPEN_SOURCE_EXTENDED 1 167 # undef _LARGEFILE64_SOURCE 168 # define _LARGEFILE64_SOURCE 1 169 # undef _BSD_SOURCE 170 # define _BSD_SOURCE 1 171 # undef _SVID_SOURCE 172 # define _SVID_SOURCE 1 173 # undef _ATFILE_SOURCE 174 # define _ATFILE_SOURCE 1 175 #endif 176 177 /* If nothing (other than _GNU_SOURCE) is defined, 178 define _BSD_SOURCE and _SVID_SOURCE. */ 179 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 180 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 181 !defined _XOPEN_SOURCE && !defined _BSD_SOURCE && !defined _SVID_SOURCE) 182 # define _BSD_SOURCE 1 183 # define _SVID_SOURCE 1 184 #endif 185 186 /* This is to enable the ISO C99 extension. Also recognize the old macro 187 which was used prior to the standard acceptance. This macro will 188 eventually go away and the features enabled by default once the ISO C99 189 standard is widely adopted. */ 190 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 191 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 192 # define __USE_ISOC99 1 193 #endif 194 195 /* This is to enable the ISO C90 Amendment 1:1995 extension. */ 196 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 197 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 198 # define __USE_ISOC95 1 199 #endif 200 201 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 202 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 203 #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 204 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 205 # define _POSIX_SOURCE 1 206 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 207 # define _POSIX_C_SOURCE 2 208 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 209 # define _POSIX_C_SOURCE 199506L 210 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 211 # define _POSIX_C_SOURCE 200112L 212 # else 213 # define _POSIX_C_SOURCE 200809L 214 # endif 215 # define __USE_POSIX_IMPLICITLY 1 216 #endif 217 218 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 219 # define __USE_POSIX 1 220 #endif 221 222 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 223 # define __USE_POSIX2 1 224 #endif 225 226 #if (_POSIX_C_SOURCE - 0) >= 199309L 227 # define __USE_POSIX199309 1 228 #endif 229 230 #if (_POSIX_C_SOURCE - 0) >= 199506L 231 # define __USE_POSIX199506 1 232 #endif 233 234 #if (_POSIX_C_SOURCE - 0) >= 200112L 235 # define __USE_XOPEN2K 1 236 # undef __USE_ISOC95 237 # define __USE_ISOC95 1 238 # undef __USE_ISOC99 239 # define __USE_ISOC99 1 240 #endif 241 242 #if (_POSIX_C_SOURCE - 0) >= 200809L 243 # define __USE_XOPEN2K8 1 244 # undef _ATFILE_SOURCE 245 # define _ATFILE_SOURCE 1 246 #endif 247 248 #ifdef _XOPEN_SOURCE 249 # define __USE_XOPEN 1 250 # if (_XOPEN_SOURCE - 0) >= 500 251 # define __USE_XOPEN_EXTENDED 1 252 # define __USE_UNIX98 1 253 # undef _LARGEFILE_SOURCE 254 # define _LARGEFILE_SOURCE 1 255 # if (_XOPEN_SOURCE - 0) >= 600 256 # if (_XOPEN_SOURCE - 0) >= 700 257 # define __USE_XOPEN2K8 1 258 # define __USE_XOPEN2K8XSI 1 259 # endif 260 # define __USE_XOPEN2K 1 261 # define __USE_XOPEN2KXSI 1 262 # undef __USE_ISOC95 263 # define __USE_ISOC95 1 264 # undef __USE_ISOC99 265 # define __USE_ISOC99 1 266 # endif 267 # else 268 # ifdef _XOPEN_SOURCE_EXTENDED 269 # define __USE_XOPEN_EXTENDED 1 270 # endif 271 # endif 272 #endif 273 274 #ifdef _LARGEFILE_SOURCE 275 # define __USE_LARGEFILE 1 276 #endif 277 278 #ifdef _LARGEFILE64_SOURCE 279 # define __USE_LARGEFILE64 1 280 #endif 281 282 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 283 # define __USE_FILE_OFFSET64 1 284 #endif 285 286 #if defined _BSD_SOURCE || defined _SVID_SOURCE 287 # define __USE_MISC 1 288 #endif 289 290 #ifdef _BSD_SOURCE 291 # define __USE_BSD 1 292 #endif 293 294 #ifdef _SVID_SOURCE 295 # define __USE_SVID 1 296 #endif 297 298 #ifdef _ATFILE_SOURCE 299 # define __USE_ATFILE 1 300 #endif 301 302 #ifdef _GNU_SOURCE 303 # define __USE_GNU 1 304 #endif 305 306 #if defined _REENTRANT || defined _THREAD_SAFE 307 # define __USE_REENTRANT 1 308 #endif 309 310 #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 311 && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 312 # if !__GNUC_PREREQ (4, 1) 313 # ifdef __GNUC_RH_RELEASE__ 314 # warning _FORTIFY_SOURCE supported only with GCC 4.1 and later 315 # endif 316 # define __USE_FORTIFY_LEVEL 0 317 # elif _FORTIFY_SOURCE > 1 318 # define __USE_FORTIFY_LEVEL 2 319 # else 320 # define __USE_FORTIFY_LEVEL 1 321 # endif 322 #else 323 # define __USE_FORTIFY_LEVEL 0 324 #endif 325 326 /* We do support the IEC 559 math functionality, real and complex. */ 327 #define __STDC_IEC_559__ 1 328 #define __STDC_IEC_559_COMPLEX__ 1 329 330 /* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 331 #define __STDC_ISO_10646__ 200009L 332 333 /* This macro indicates that the installed library is the GNU C Library. 334 For historic reasons the value now is 6 and this will stay from now 335 on. The use of this variable is deprecated. Use __GLIBC__ and 336 __GLIBC_MINOR__ now (see below) when you want to test for a specific 337 GNU C library version and use the values in <gnu/lib-names.h> to get 338 the sonames of the shared libraries. */ 339 #undef __GNU_LIBRARY__ 340 #define __GNU_LIBRARY__ 6 341 342 /* Major and minor version number of the GNU C library package. Use 343 these macros to test for features in specific releases. */ 344 #define __GLIBC__ 2 345 #define __GLIBC_MINOR__ 12 346 347 #define __GLIBC_PREREQ(maj, min) \ 348 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 349 350 /* Decide whether a compiler supports the long long datatypes. */ 351 #if defined __GNUC__ \ 352 || (defined __PGI && defined __i386__ ) \ 353 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 354 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 355 # define __GLIBC_HAVE_LONG_LONG 1 356 #endif 357 358 /* This is here only because every header file already includes this one. */ 359 #ifndef __ASSEMBLER__ 360 # ifndef _SYS_CDEFS_H 361 # include <sys/cdefs.h> 362 # endif 363 364 /* If we don't have __REDIRECT, prototypes will be missing if 365 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 366 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 367 # define __USE_LARGEFILE 1 368 # define __USE_LARGEFILE64 1 369 # endif 370 371 #endif /* !ASSEMBLER */ 372 373 /* Decide whether we can define 'extern inline' functions in headers. */ 374 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 375 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 376 && defined __extern_inline 377 # define __USE_EXTERN_INLINES 1 378 #endif 379 380 381 /* This is here only because every header file already includes this one. 382 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 383 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 384 that will always return failure (and set errno to ENOSYS). */ 385 #include <gnu/stubs.h> 386 387 388 #endif /* features.h */ 389