1 /* Copyright (C) 1991-1993,1995-2007,2009,2010,2011 2 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, write to the Free 17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 18 02111-1307 USA. */ 19 20 #ifndef _FEATURES_H 21 #define _FEATURES_H 1 22 23 /* These are defined by the user (or the compiler) 24 to specify the desired environment: 25 26 __STRICT_ANSI__ ISO Standard C. 27 _ISOC99_SOURCE Extensions to ISO C89 from ISO C99. 28 _POSIX_SOURCE IEEE Std 1003.1. 29 _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2; 30 if >=199309L, add IEEE Std 1003.1b-1993; 31 if >=199506L, add IEEE Std 1003.1c-1995; 32 if >=200112L, all of IEEE 1003.1-2004 33 if >=200809L, all of IEEE 1003.1-2008 34 _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if 35 Single Unix conformance is wanted, to 600 for the 36 sixth revision, to 700 for the seventh revision. 37 _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions. 38 _LARGEFILE_SOURCE Some more functions for correct standard I/O. 39 _LARGEFILE64_SOURCE Additional functionality from LFS for large files. 40 _FILE_OFFSET_BITS=N Select default filesystem interface. 41 _BSD_SOURCE ISO C, POSIX, and 4.3BSD things. 42 _SVID_SOURCE ISO C, POSIX, and SVID things. 43 _ATFILE_SOURCE Additional *at interfaces. 44 _GNU_SOURCE All of the above, plus GNU extensions. 45 _REENTRANT Select additionally reentrant object. 46 _THREAD_SAFE Same as _REENTRANT, often used by other systems. 47 _FORTIFY_SOURCE If set to numeric value > 0 additional security 48 measures are defined, according to level. 49 50 The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__. 51 If none of these are defined, the default is to have _SVID_SOURCE, 52 _BSD_SOURCE, and _POSIX_SOURCE set to one and _POSIX_C_SOURCE set to 53 200112L. If more than one of these are defined, they accumulate. 54 For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE 55 together give you ISO C, 1003.1, and 1003.2, but nothing else. 56 57 These are defined by this file and are used by the 58 header files to decide what to declare or define: 59 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_ISOC99 99 #undef __USE_ISOC95 100 #undef __USE_POSIX 101 #undef __USE_POSIX2 102 #undef __USE_POSIX199309 103 #undef __USE_POSIX199506 104 #undef __USE_XOPEN 105 #undef __USE_XOPEN_EXTENDED 106 #undef __USE_UNIX98 107 #undef __USE_XOPEN2K 108 #undef __USE_XOPEN2KXSI 109 #undef __USE_XOPEN2K8 110 #undef __USE_XOPEN2K8XSI 111 #undef __USE_LARGEFILE 112 #undef __USE_LARGEFILE64 113 #undef __USE_FILE_OFFSET64 114 #undef __USE_BSD 115 #undef __USE_SVID 116 #undef __USE_MISC 117 #undef __USE_ATFILE 118 #undef __USE_GNU 119 #undef __USE_REENTRANT 120 #undef __USE_FORTIFY_LEVEL 121 #undef __FAVOR_BSD 122 #undef __KERNEL_STRICT_NAMES 123 124 /* Suppress kernel-name space pollution unless user expressedly asks 125 for it. */ 126 #ifndef _LOOSE_KERNEL_NAMES 127 # define __KERNEL_STRICT_NAMES 128 #endif 129 130 /* Always use ISO C things. */ 131 #define __USE_ANSI 1 132 133 /* Convenience macros to test the versions of glibc and gcc. 134 Use them like this: 135 #if __GNUC_PREREQ (2,8) 136 ... code requiring gcc 2.8 or later ... 137 #endif 138 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 139 were not defined then. */ 140 #if defined __GNUC__ && defined __GNUC_MINOR__ 141 # define __GNUC_PREREQ(maj, min) \ 142 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 143 #else 144 # define __GNUC_PREREQ(maj, min) 0 145 #endif 146 147 148 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 149 #if defined _BSD_SOURCE && \ 150 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 151 defined _XOPEN_SOURCE || defined _GNU_SOURCE || defined _SVID_SOURCE) 152 # define __FAVOR_BSD 1 153 #endif 154 155 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 156 #ifdef _GNU_SOURCE 157 # undef _ISOC95_SOURCE 158 # define _ISOC95_SOURCE 1 159 # undef _ISOC99_SOURCE 160 # define _ISOC99_SOURCE 1 161 # undef _POSIX_SOURCE 162 # define _POSIX_SOURCE 1 163 # undef _POSIX_C_SOURCE 164 # define _POSIX_C_SOURCE 200809L 165 # undef _XOPEN_SOURCE 166 # define _XOPEN_SOURCE 700 167 # undef _XOPEN_SOURCE_EXTENDED 168 # define _XOPEN_SOURCE_EXTENDED 1 169 # undef _LARGEFILE64_SOURCE 170 # define _LARGEFILE64_SOURCE 1 171 # undef _BSD_SOURCE 172 # define _BSD_SOURCE 1 173 # undef _SVID_SOURCE 174 # define _SVID_SOURCE 1 175 # undef _ATFILE_SOURCE 176 # define _ATFILE_SOURCE 1 177 #endif 178 179 /* If nothing (other than _GNU_SOURCE) is defined, 180 define _BSD_SOURCE and _SVID_SOURCE. */ 181 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 182 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 183 !defined _XOPEN_SOURCE && !defined _BSD_SOURCE && !defined _SVID_SOURCE) 184 # define _BSD_SOURCE 1 185 # define _SVID_SOURCE 1 186 #endif 187 188 /* This is to enable the ISO C99 extension. Also recognize the old macro 189 which was used prior to the standard acceptance. This macro will 190 eventually go away and the features enabled by default once the ISO C99 191 standard is widely adopted. */ 192 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 193 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 194 # define __USE_ISOC99 1 195 #endif 196 197 /* This is to enable the ISO C90 Amendment 1:1995 extension. */ 198 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 199 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 200 # define __USE_ISOC95 1 201 #endif 202 203 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 204 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 205 #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 206 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 207 # define _POSIX_SOURCE 1 208 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 209 # define _POSIX_C_SOURCE 2 210 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 211 # define _POSIX_C_SOURCE 199506L 212 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 213 # define _POSIX_C_SOURCE 200112L 214 # else 215 # define _POSIX_C_SOURCE 200809L 216 # endif 217 # define __USE_POSIX_IMPLICITLY 1 218 #endif 219 220 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 221 # define __USE_POSIX 1 222 #endif 223 224 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 225 # define __USE_POSIX2 1 226 #endif 227 228 #if (_POSIX_C_SOURCE - 0) >= 199309L 229 # define __USE_POSIX199309 1 230 #endif 231 232 #if (_POSIX_C_SOURCE - 0) >= 199506L 233 # define __USE_POSIX199506 1 234 #endif 235 236 #if (_POSIX_C_SOURCE - 0) >= 200112L 237 # define __USE_XOPEN2K 1 238 # undef __USE_ISOC95 239 # define __USE_ISOC95 1 240 # undef __USE_ISOC99 241 # define __USE_ISOC99 1 242 #endif 243 244 #if (_POSIX_C_SOURCE - 0) >= 200809L 245 # define __USE_XOPEN2K8 1 246 # undef _ATFILE_SOURCE 247 # define _ATFILE_SOURCE 1 248 #endif 249 250 #ifdef _XOPEN_SOURCE 251 # define __USE_XOPEN 1 252 # if (_XOPEN_SOURCE - 0) >= 500 253 # define __USE_XOPEN_EXTENDED 1 254 # define __USE_UNIX98 1 255 # undef _LARGEFILE_SOURCE 256 # define _LARGEFILE_SOURCE 1 257 # if (_XOPEN_SOURCE - 0) >= 600 258 # if (_XOPEN_SOURCE - 0) >= 700 259 # define __USE_XOPEN2K8 1 260 # define __USE_XOPEN2K8XSI 1 261 # endif 262 # define __USE_XOPEN2K 1 263 # define __USE_XOPEN2KXSI 1 264 # undef __USE_ISOC95 265 # define __USE_ISOC95 1 266 # undef __USE_ISOC99 267 # define __USE_ISOC99 1 268 # endif 269 # else 270 # ifdef _XOPEN_SOURCE_EXTENDED 271 # define __USE_XOPEN_EXTENDED 1 272 # endif 273 # endif 274 #endif 275 276 #ifdef _LARGEFILE_SOURCE 277 # define __USE_LARGEFILE 1 278 #endif 279 280 #ifdef _LARGEFILE64_SOURCE 281 # define __USE_LARGEFILE64 1 282 #endif 283 284 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 285 # define __USE_FILE_OFFSET64 1 286 #endif 287 288 #if defined _BSD_SOURCE || defined _SVID_SOURCE 289 # define __USE_MISC 1 290 #endif 291 292 #ifdef _BSD_SOURCE 293 # define __USE_BSD 1 294 #endif 295 296 #ifdef _SVID_SOURCE 297 # define __USE_SVID 1 298 #endif 299 300 #ifdef _ATFILE_SOURCE 301 # define __USE_ATFILE 1 302 #endif 303 304 #ifdef _GNU_SOURCE 305 # define __USE_GNU 1 306 #endif 307 308 #if defined _REENTRANT || defined _THREAD_SAFE 309 # define __USE_REENTRANT 1 310 #endif 311 312 #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 313 && __GNUC_PREREQ (4, 1) && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 314 # if _FORTIFY_SOURCE > 1 315 # define __USE_FORTIFY_LEVEL 2 316 # else 317 # define __USE_FORTIFY_LEVEL 1 318 # endif 319 #else 320 # define __USE_FORTIFY_LEVEL 0 321 #endif 322 323 /* Define __STDC_IEC_559__ and other similar macros. */ 324 #include <bits/predefs.h> 325 326 /* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 327 #define __STDC_ISO_10646__ 200009L 328 329 /* This macro indicates that the installed library is the GNU C Library. 330 For historic reasons the value now is 6 and this will stay from now 331 on. The use of this variable is deprecated. Use __GLIBC__ and 332 __GLIBC_MINOR__ now (see below) when you want to test for a specific 333 GNU C library version and use the values in <gnu/lib-names.h> to get 334 the sonames of the shared libraries. */ 335 #undef __GNU_LIBRARY__ 336 #define __GNU_LIBRARY__ 6 337 338 /* Major and minor version number of the GNU C library package. Use 339 these macros to test for features in specific releases. */ 340 #define __GLIBC__ 2 341 #define __GLIBC_MINOR__ 15 342 343 #define __GLIBC_PREREQ(maj, min) \ 344 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 345 346 /* Decide whether a compiler supports the long long datatypes. */ 347 #if defined __GNUC__ \ 348 || (defined __PGI && defined __i386__ ) \ 349 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 350 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 351 # define __GLIBC_HAVE_LONG_LONG 1 352 #endif 353 354 /* This is here only because every header file already includes this one. */ 355 #ifndef __ASSEMBLER__ 356 # ifndef _SYS_CDEFS_H 357 # include <sys/cdefs.h> 358 # endif 359 360 /* If we don't have __REDIRECT, prototypes will be missing if 361 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 362 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 363 # define __USE_LARGEFILE 1 364 # define __USE_LARGEFILE64 1 365 # endif 366 367 #endif /* !ASSEMBLER */ 368 369 /* Decide whether we can define 'extern inline' functions in headers. */ 370 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 371 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 372 && defined __extern_inline 373 # define __USE_EXTERN_INLINES 1 374 #endif 375 376 /* There are some functions that must be declared 'extern inline' even with 377 -Os when building LIBC, or they'll end up undefined. */ 378 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 379 && (defined _LIBC || !defined __OPTIMIZE_SIZE__) && !defined __NO_INLINE__ \ 380 && defined __extern_inline 381 # define __USE_EXTERN_INLINES_IN_LIBC 1 382 #endif 383 384 385 /* This is here only because every header file already includes this one. 386 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 387 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 388 that will always return failure (and set errno to ENOSYS). */ 389 #include <gnu/stubs.h> 390 391 392 #endif /* features.h */ 393