1 /* Copyright (C) 1991-1993,1995-2000,2001,2002 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 _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if 32 Single Unix conformance is wanted, to 600 for the 33 upcoming sixth revision. 34 _XOPEN_SOURCE_EXTENDED XPG things and X/Open Unix extensions. 35 _LARGEFILE_SOURCE Some more functions for correct standard I/O. 36 _LARGEFILE64_SOURCE Additional functionality from LFS for large files. 37 _FILE_OFFSET_BITS=N Select default filesystem interface. 38 _BSD_SOURCE ISO C, POSIX, and 4.3BSD things. 39 _SVID_SOURCE ISO C, POSIX, and SVID things. 40 _GNU_SOURCE All of the above, plus GNU extensions. 41 _REENTRANT Select additionally reentrant object. 42 _THREAD_SAFE Same as _REENTRANT, often used by other systems. 43 44 The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__. 45 If none of these are defined, the default is to have _SVID_SOURCE, 46 _BSD_SOURCE, and _POSIX_SOURCE set to one and _POSIX_C_SOURCE set to 47 199506L. If more than one of these are defined, they accumulate. 48 For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE 49 together give you ISO C, 1003.1, and 1003.2, but nothing else. 50 51 These are defined by this file and are used by the 52 header files to decide what to declare or define: 53 54 __USE_ISOC99 Define ISO C99 things. 55 __USE_POSIX Define IEEE Std 1003.1 things. 56 __USE_POSIX2 Define IEEE Std 1003.2 things. 57 __USE_POSIX199309 Define IEEE Std 1003.1, and .1b things. 58 __USE_POSIX199506 Define IEEE Std 1003.1, .1b, .1c and .1i things. 59 __USE_XOPEN Define XPG things. 60 __USE_XOPEN_EXTENDED Define X/Open Unix things. 61 __USE_UNIX98 Define Single Unix V2 things. 62 __USE_XOPEN2K Define XPG6 things. 63 __USE_LARGEFILE Define correct standard I/O things. 64 __USE_LARGEFILE64 Define LFS things with separate names. 65 __USE_FILE_OFFSET64 Define 64bit interface as default. 66 __USE_BSD Define 4.3BSD things. 67 __USE_SVID Define SVID things. 68 __USE_MISC Define things common to BSD and System V Unix. 69 __USE_GNU Define GNU extensions. 70 __USE_REENTRANT Define reentrant/thread-safe *_r functions. 71 __FAVOR_BSD Favor 4.3BSD things in cases of conflict. 72 73 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are 74 defined by this file unconditionally. `__GNU_LIBRARY__' is provided 75 only for compatibility. All new code should use the other symbols 76 to test for features. 77 78 All macros listed above as possibly being defined by this file are 79 explicitly undefined if they are not explicitly defined. 80 Feature-test macros that are not defined by the user or compiler 81 but are implied by the other feature-test macros defined (or by the 82 lack of any definitions) are defined by the file. */ 83 84 85 /* Undefine everything, so we get a clean slate. */ 86 #undef __USE_ISOC99 87 #undef __USE_POSIX 88 #undef __USE_POSIX2 89 #undef __USE_POSIX199309 90 #undef __USE_POSIX199506 91 #undef __USE_XOPEN 92 #undef __USE_XOPEN_EXTENDED 93 #undef __USE_UNIX98 94 #undef __USE_XOPEN2K 95 #undef __USE_LARGEFILE 96 #undef __USE_LARGEFILE64 97 #undef __USE_FILE_OFFSET64 98 #undef __USE_BSD 99 #undef __USE_SVID 100 #undef __USE_MISC 101 #undef __USE_GNU 102 #undef __USE_REENTRANT 103 #undef __FAVOR_BSD 104 #undef __KERNEL_STRICT_NAMES 105 106 /* Suppress kernel-name space pollution unless user expressedly asks 107 for it. */ 108 #ifndef _LOOSE_KERNEL_NAMES 109 # define __KERNEL_STRICT_NAMES 110 #endif 111 112 /* Always use ISO C things. */ 113 #define __USE_ANSI 1 114 115 116 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 117 #if defined _BSD_SOURCE && \ 118 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 119 defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \ 120 defined _GNU_SOURCE || defined _SVID_SOURCE) 121 # define __FAVOR_BSD 1 122 #endif 123 124 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 125 #ifdef _GNU_SOURCE 126 # undef _ISOC99_SOURCE 127 # define _ISOC99_SOURCE 1 128 # undef _POSIX_SOURCE 129 # define _POSIX_SOURCE 1 130 # undef _POSIX_C_SOURCE 131 # define _POSIX_C_SOURCE 199506L 132 # undef _XOPEN_SOURCE 133 # define _XOPEN_SOURCE 600 134 # undef _XOPEN_SOURCE_EXTENDED 135 # define _XOPEN_SOURCE_EXTENDED 1 136 # undef _LARGEFILE64_SOURCE 137 # define _LARGEFILE64_SOURCE 1 138 # undef _BSD_SOURCE 139 # define _BSD_SOURCE 1 140 # undef _SVID_SOURCE 141 # define _SVID_SOURCE 1 142 #endif 143 144 /* If nothing (other than _GNU_SOURCE) is defined, 145 define _BSD_SOURCE and _SVID_SOURCE. */ 146 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 147 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 148 !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \ 149 !defined _BSD_SOURCE && !defined _SVID_SOURCE) 150 # define _BSD_SOURCE 1 151 # define _SVID_SOURCE 1 152 #endif 153 154 /* This is to enable the ISO C99 extension. Also recognize the old macro 155 which was used prior to the standard acceptance. This macro will 156 eventually go away and the features enabled by default once the ISO C99 157 standard is widely adopted. */ 158 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 159 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 160 # define __USE_ISOC99 1 161 #endif 162 163 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 164 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 165 #if (!defined __STRICT_ANSI__ && !defined _POSIX_SOURCE && \ 166 !defined _POSIX_C_SOURCE) 167 # define _POSIX_SOURCE 1 168 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 169 # define _POSIX_C_SOURCE 2 170 # else 171 # define _POSIX_C_SOURCE 199506L 172 # endif 173 #endif 174 175 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 176 # define __USE_POSIX 1 177 #endif 178 179 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 180 # define __USE_POSIX2 1 181 #endif 182 183 #if (_POSIX_C_SOURCE - 0) >= 199309L 184 # define __USE_POSIX199309 1 185 #endif 186 187 #if (_POSIX_C_SOURCE - 0) >= 199506L 188 # define __USE_POSIX199506 1 189 #endif 190 191 #ifdef _XOPEN_SOURCE 192 # define __USE_XOPEN 1 193 # if (_XOPEN_SOURCE - 0) >= 500 194 # define __USE_XOPEN_EXTENDED 1 195 # define __USE_UNIX98 1 196 # undef _LARGEFILE_SOURCE 197 # define _LARGEFILE_SOURCE 1 198 # if (_XOPEN_SOURCE - 0) >= 600 199 # define __USE_XOPEN2K 1 200 # undef __USE_ISOC99 201 # define __USE_ISOC99 1 202 # endif 203 # else 204 # ifdef _XOPEN_SOURCE_EXTENDED 205 # define __USE_XOPEN_EXTENDED 1 206 # endif 207 # endif 208 #endif 209 210 #ifdef _LARGEFILE_SOURCE 211 # define __USE_LARGEFILE 1 212 #endif 213 214 #ifdef _LARGEFILE64_SOURCE 215 # define __USE_LARGEFILE64 1 216 #endif 217 218 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 219 # define __USE_FILE_OFFSET64 1 220 #endif 221 222 #if defined _BSD_SOURCE || defined _SVID_SOURCE 223 # define __USE_MISC 1 224 #endif 225 226 #ifdef _BSD_SOURCE 227 # define __USE_BSD 1 228 #endif 229 230 #ifdef _SVID_SOURCE 231 # define __USE_SVID 1 232 #endif 233 234 #ifdef _GNU_SOURCE 235 # define __USE_GNU 1 236 #endif 237 238 #if defined _REENTRANT || defined _THREAD_SAFE 239 # define __USE_REENTRANT 1 240 #endif 241 242 /* We do support the IEC 559 math functionality, real and complex. */ 243 #define __STDC_IEC_559__ 1 244 #define __STDC_IEC_559_COMPLEX__ 1 245 246 /* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 247 #ifndef __STDC_ISO_10646__ 248 #define __STDC_ISO_10646__ 200009L 249 #endif 250 251 /* This macro indicates that the installed library is the GNU C Library. 252 For historic reasons the value now is 6 and this will stay from now 253 on. The use of this variable is deprecated. Use __GLIBC__ and 254 __GLIBC_MINOR__ now (see below) when you want to test for a specific 255 GNU C library version and use the values in <gnu/lib-names.h> to get 256 the sonames of the shared libraries. */ 257 #undef __GNU_LIBRARY__ 258 #define __GNU_LIBRARY__ 6 259 260 /* Major and minor version number of the GNU C library package. Use 261 these macros to test for features in specific releases. */ 262 #define __GLIBC__ 2 263 #define __GLIBC_MINOR__ 3 264 265 /* Convenience macros to test the versions of glibc and gcc. 266 Use them like this: 267 #if __GNUC_PREREQ (2,8) 268 ... code requiring gcc 2.8 or later ... 269 #endif 270 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 271 were not defined then. */ 272 #if defined __GNUC__ && defined __GNUC_MINOR__ 273 # define __GNUC_PREREQ(maj, min) \ 274 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 275 #else 276 # define __GNUC_PREREQ(maj, min) 0 277 #endif 278 279 #define __GLIBC_PREREQ(maj, min) \ 280 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 281 282 /* Decide whether a compiler supports the long long datatypes. */ 283 #if defined __GNUC__ \ 284 || (defined __PGI && defined __i386__ ) \ 285 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 286 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 287 # define __GLIBC_HAVE_LONG_LONG 1 288 #endif 289 290 /* This is here only because every header file already includes this one. */ 291 #ifndef __ASSEMBLER__ 292 # ifndef _SYS_CDEFS_H 293 # include <sys/cdefs.h> 294 # endif 295 296 /* If we don't have __REDIRECT, prototypes will be missing if 297 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 298 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 299 # define __USE_LARGEFILE 1 300 # define __USE_LARGEFILE64 1 301 # endif 302 303 #endif /* !ASSEMBLER */ 304 305 /* Decide whether we can define 'extern inline' functions in headers. */ 306 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 307 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ 308 # define __USE_EXTERN_INLINES 1 309 #endif 310 311 312 /* This is here only because every header file already includes this one. 313 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 314 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 315 that will always return failure (and set errno to ENOSYS). */ 316 #include <gnu/stubs.h> 317 318 319 #endif /* features.h */ 320