1 /* Copyright (C) 1991,1992,1993,1995-2006,2007 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 _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if 33 Single Unix conformance is wanted, to 600 for the 34 upcoming sixth revision. 35 _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions. 36 _LARGEFILE_SOURCE Some more functions for correct standard I/O. 37 _LARGEFILE64_SOURCE Additional functionality from LFS for large files. 38 _FILE_OFFSET_BITS=N Select default filesystem interface. 39 _BSD_SOURCE ISO C, POSIX, and 4.3BSD things. 40 _SVID_SOURCE ISO C, POSIX, and SVID things. 41 _ATFILE_SOURCE Additional *at interfaces. 42 _GNU_SOURCE All of the above, plus GNU extensions. 43 _REENTRANT Select additionally reentrant object. 44 _THREAD_SAFE Same as _REENTRANT, often used by other systems. 45 _FORTIFY_SOURCE If set to numeric value > 0 additional security 46 measures are defined, according to level. 47 48 The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__. 49 If none of these are defined, the default is to have _SVID_SOURCE, 50 _BSD_SOURCE, and _POSIX_SOURCE set to one and _POSIX_C_SOURCE set to 51 200112L. If more than one of these are defined, they accumulate. 52 For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE 53 together give you ISO C, 1003.1, and 1003.2, but nothing else. 54 55 These are defined by this file and are used by the 56 header files to decide what to declare or define: 57 58 __USE_ISOC99 Define ISO C99 things. 59 __USE_ISOC95 Define ISO C90 AMD1 (C95) things. 60 __USE_POSIX Define IEEE Std 1003.1 things. 61 __USE_POSIX2 Define IEEE Std 1003.2 things. 62 __USE_POSIX199309 Define IEEE Std 1003.1, and .1b things. 63 __USE_POSIX199506 Define IEEE Std 1003.1, .1b, .1c and .1i things. 64 __USE_XOPEN Define XPG things. 65 __USE_XOPEN_EXTENDED Define X/Open Unix things. 66 __USE_UNIX98 Define Single Unix V2 things. 67 __USE_XOPEN2K Define XPG6 things. 68 __USE_LARGEFILE Define correct standard I/O things. 69 __USE_LARGEFILE64 Define LFS things with separate names. 70 __USE_FILE_OFFSET64 Define 64bit interface as default. 71 __USE_BSD Define 4.3BSD things. 72 __USE_SVID Define SVID things. 73 __USE_MISC Define things common to BSD and System V Unix. 74 __USE_ATFILE Define *at interfaces and AT_* constants for them. 75 __USE_GNU Define GNU extensions. 76 __USE_REENTRANT Define reentrant/thread-safe *_r functions. 77 __USE_FORTIFY_LEVEL Additional security measures used, according to level. 78 __FAVOR_BSD Favor 4.3BSD things in cases of conflict. 79 80 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are 81 defined by this file unconditionally. `__GNU_LIBRARY__' is provided 82 only for compatibility. All new code should use the other symbols 83 to test for features. 84 85 All macros listed above as possibly being defined by this file are 86 explicitly undefined if they are not explicitly defined. 87 Feature-test macros that are not defined by the user or compiler 88 but are implied by the other feature-test macros defined (or by the 89 lack of any definitions) are defined by the file. */ 90 91 92 /* Undefine everything, so we get a clean slate. */ 93 #undef __USE_ISOC99 94 #undef __USE_ISOC95 95 #undef __USE_POSIX 96 #undef __USE_POSIX2 97 #undef __USE_POSIX199309 98 #undef __USE_POSIX199506 99 #undef __USE_XOPEN 100 #undef __USE_XOPEN_EXTENDED 101 #undef __USE_UNIX98 102 #undef __USE_XOPEN2K 103 #undef __USE_LARGEFILE 104 #undef __USE_LARGEFILE64 105 #undef __USE_FILE_OFFSET64 106 #undef __USE_BSD 107 #undef __USE_SVID 108 #undef __USE_MISC 109 #undef __USE_ATFILE 110 #undef __USE_GNU 111 #undef __USE_REENTRANT 112 #undef __USE_FORTIFY_LEVEL 113 #undef __FAVOR_BSD 114 #undef __KERNEL_STRICT_NAMES 115 116 /* Suppress kernel-name space pollution unless user expressedly asks 117 for it. */ 118 #ifndef _LOOSE_KERNEL_NAMES 119 # define __KERNEL_STRICT_NAMES 120 #endif 121 122 /* Always use ISO C things. */ 123 #define __USE_ANSI 1 124 125 /* Convenience macros to test the versions of glibc and gcc. 126 Use them like this: 127 #if __GNUC_PREREQ (2,8) 128 ... code requiring gcc 2.8 or later ... 129 #endif 130 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 131 were not defined then. */ 132 #if defined __GNUC__ && defined __GNUC_MINOR__ 133 # define __GNUC_PREREQ(maj, min) \ 134 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 135 #else 136 # define __GNUC_PREREQ(maj, min) 0 137 #endif 138 139 140 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 141 #if defined _BSD_SOURCE && \ 142 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 143 defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \ 144 defined _GNU_SOURCE || defined _SVID_SOURCE) 145 # define __FAVOR_BSD 1 146 #endif 147 148 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 149 #ifdef _GNU_SOURCE 150 # undef _ISOC99_SOURCE 151 # define _ISOC99_SOURCE 1 152 # undef _POSIX_SOURCE 153 # define _POSIX_SOURCE 1 154 # undef _POSIX_C_SOURCE 155 # define _POSIX_C_SOURCE 200112L 156 # undef _XOPEN_SOURCE 157 # define _XOPEN_SOURCE 600 158 # undef _XOPEN_SOURCE_EXTENDED 159 # define _XOPEN_SOURCE_EXTENDED 1 160 # undef _LARGEFILE64_SOURCE 161 # define _LARGEFILE64_SOURCE 1 162 # undef _BSD_SOURCE 163 # define _BSD_SOURCE 1 164 # undef _SVID_SOURCE 165 # define _SVID_SOURCE 1 166 # undef _ATFILE_SOURCE 167 # define _ATFILE_SOURCE 1 168 #endif 169 170 /* If nothing (other than _GNU_SOURCE) is defined, 171 define _BSD_SOURCE and _SVID_SOURCE. */ 172 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 173 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 174 !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \ 175 !defined _BSD_SOURCE && !defined _SVID_SOURCE) 176 # define _BSD_SOURCE 1 177 # define _SVID_SOURCE 1 178 #endif 179 180 /* This is to enable the ISO C99 extension. Also recognize the old macro 181 which was used prior to the standard acceptance. This macro will 182 eventually go away and the features enabled by default once the ISO C99 183 standard is widely adopted. */ 184 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 185 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 186 # define __USE_ISOC99 1 187 #endif 188 189 /* This is to enable the ISO C90 Amendment 1:1995 extension. */ 190 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 191 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 192 # define __USE_ISOC95 1 193 #endif 194 195 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 196 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 197 #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 198 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 199 # define _POSIX_SOURCE 1 200 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 201 # define _POSIX_C_SOURCE 2 202 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 203 # define _POSIX_C_SOURCE 199506L 204 # else 205 # define _POSIX_C_SOURCE 200112L 206 # endif 207 #endif 208 209 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 210 # define __USE_POSIX 1 211 #endif 212 213 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 214 # define __USE_POSIX2 1 215 #endif 216 217 #if (_POSIX_C_SOURCE - 0) >= 199309L 218 # define __USE_POSIX199309 1 219 #endif 220 221 #if (_POSIX_C_SOURCE - 0) >= 199506L 222 # define __USE_POSIX199506 1 223 #endif 224 225 #if (_POSIX_C_SOURCE - 0) >= 200112L 226 # define __USE_XOPEN2K 1 227 #endif 228 229 #ifdef _XOPEN_SOURCE 230 # define __USE_XOPEN 1 231 # if (_XOPEN_SOURCE - 0) >= 500 232 # define __USE_XOPEN_EXTENDED 1 233 # define __USE_UNIX98 1 234 # undef _LARGEFILE_SOURCE 235 # define _LARGEFILE_SOURCE 1 236 # if (_XOPEN_SOURCE - 0) >= 600 237 # define __USE_XOPEN2K 1 238 # undef __USE_ISOC99 239 # define __USE_ISOC99 1 240 # endif 241 # else 242 # ifdef _XOPEN_SOURCE_EXTENDED 243 # define __USE_XOPEN_EXTENDED 1 244 # endif 245 # endif 246 #endif 247 248 #ifdef _LARGEFILE_SOURCE 249 # define __USE_LARGEFILE 1 250 #endif 251 252 #ifdef _LARGEFILE64_SOURCE 253 # define __USE_LARGEFILE64 1 254 #endif 255 256 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 257 # define __USE_FILE_OFFSET64 1 258 #endif 259 260 #if defined _BSD_SOURCE || defined _SVID_SOURCE 261 # define __USE_MISC 1 262 #endif 263 264 #ifdef _BSD_SOURCE 265 # define __USE_BSD 1 266 #endif 267 268 #ifdef _SVID_SOURCE 269 # define __USE_SVID 1 270 #endif 271 272 #ifdef _ATFILE_SOURCE 273 # define __USE_ATFILE 1 274 #endif 275 276 #ifdef _GNU_SOURCE 277 # define __USE_GNU 1 278 #endif 279 280 #if defined _REENTRANT || defined _THREAD_SAFE 281 # define __USE_REENTRANT 1 282 #endif 283 284 #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 285 && __GNUC_PREREQ (4, 1) && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 286 # if _FORTIFY_SOURCE > 1 287 # define __USE_FORTIFY_LEVEL 2 288 # else 289 # define __USE_FORTIFY_LEVEL 1 290 # endif 291 #else 292 # define __USE_FORTIFY_LEVEL 0 293 #endif 294 295 /* Define __STDC_IEC_559__ and other similar macros. */ 296 #include <bits/predefs.h> 297 298 /* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 299 #define __STDC_ISO_10646__ 200009L 300 301 /* This macro indicates that the installed library is the GNU C Library. 302 For historic reasons the value now is 6 and this will stay from now 303 on. The use of this variable is deprecated. Use __GLIBC__ and 304 __GLIBC_MINOR__ now (see below) when you want to test for a specific 305 GNU C library version and use the values in <gnu/lib-names.h> to get 306 the sonames of the shared libraries. */ 307 #undef __GNU_LIBRARY__ 308 #define __GNU_LIBRARY__ 6 309 310 /* Major and minor version number of the GNU C library package. Use 311 these macros to test for features in specific releases. */ 312 #define __GLIBC__ 2 313 #define __GLIBC_MINOR__ 8 314 315 #define __GLIBC_PREREQ(maj, min) \ 316 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 317 318 /* Decide whether a compiler supports the long long datatypes. */ 319 #if defined __GNUC__ \ 320 || (defined __PGI && defined __i386__ ) \ 321 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 322 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 323 # define __GLIBC_HAVE_LONG_LONG 1 324 #endif 325 326 /* This is here only because every header file already includes this one. */ 327 #ifndef __ASSEMBLER__ 328 # ifndef _SYS_CDEFS_H 329 # include <sys/cdefs.h> 330 # endif 331 332 /* If we don't have __REDIRECT, prototypes will be missing if 333 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 334 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 335 # define __USE_LARGEFILE 1 336 # define __USE_LARGEFILE64 1 337 # endif 338 339 #endif /* !ASSEMBLER */ 340 341 /* Decide whether we can define 'extern inline' functions in headers. */ 342 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 343 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 344 && defined __extern_inline 345 # define __USE_EXTERN_INLINES 1 346 #endif 347 348 /* There are some functions that must be declared 'extern inline' even with 349 -Os when building LIBC, or they'll end up undefined. */ 350 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 351 && (defined _LIBC || !defined __OPTIMIZE_SIZE__) && !defined __NO_INLINE__ \ 352 && defined __extern_inline 353 # define __USE_EXTERN_INLINES_IN_LIBC 1 354 #endif 355 356 357 /* This is here only because every header file already includes this one. 358 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 359 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 360 that will always return failure (and set errno to ENOSYS). */ 361 #include <gnu/stubs.h> 362 363 364 #endif /* features.h */ 365