1 /* Copyright (C) 1991-1993,1995-2006,2007,2009 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 _POSIX_SOURCE IEEE Std 1003.1. 27 _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2; 28 if >=199309L, add IEEE Std 1003.1b-1993; 29 if >=199506L, add IEEE Std 1003.1c-1995; 30 if >=200112L, all of IEEE 1003.1-2004 31 if >=200809L, all of IEEE 1003.1-2008 32 _XOPEN_SOURCE Includes POSIX and XPG things. Set to 500 if 33 Single Unix conformance is wanted, to 600 for the 34 sixth revision, to 700 for the seventh 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_XOPEN2K8 Define XPG7 things. 69 __USE_LARGEFILE Define correct standard I/O things. 70 __USE_LARGEFILE64 Define LFS things with separate names. 71 __USE_FILE_OFFSET64 Define 64bit interface as default. 72 __USE_BSD Define 4.3BSD things. 73 __USE_SVID Define SVID things. 74 __USE_MISC Define things common to BSD and System V Unix. 75 __USE_ATFILE Define *at interfaces and AT_* constants for them. 76 __USE_GNU Define GNU extensions. 77 __USE_REENTRANT Define reentrant/thread-safe *_r functions. 78 __USE_FORTIFY_LEVEL Additional security measures used, according to level. 79 __FAVOR_BSD Favor 4.3BSD things in cases of conflict. 80 81 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are 82 defined by this file unconditionally. `__GNU_LIBRARY__' is provided 83 only for compatibility. All new code should use the other symbols 84 to test for features. 85 86 All macros listed above as possibly being defined by this file are 87 explicitly undefined if they are not explicitly defined. 88 Feature-test macros that are not defined by the user or compiler 89 but are implied by the other feature-test macros defined (or by the 90 lack of any definitions) are defined by the file. */ 91 92 93 /* Undefine everything, so we get a clean slate. */ 94 #undef __USE_ISOC99 95 #undef __USE_ISOC95 96 #undef __USE_POSIX 97 #undef __USE_POSIX2 98 #undef __USE_POSIX199309 99 #undef __USE_POSIX199506 100 #undef __USE_XOPEN 101 #undef __USE_XOPEN_EXTENDED 102 #undef __USE_UNIX98 103 #undef __USE_XOPEN2K 104 #undef __USE_XOPEN2K8 105 #undef __USE_LARGEFILE 106 #undef __USE_LARGEFILE64 107 #undef __USE_FILE_OFFSET64 108 #undef __USE_BSD 109 #undef __USE_SVID 110 #undef __USE_MISC 111 #undef __USE_ATFILE 112 #undef __USE_GNU 113 #undef __USE_REENTRANT 114 #undef __USE_FORTIFY_LEVEL 115 #undef __FAVOR_BSD 116 #undef __KERNEL_STRICT_NAMES 117 118 /* Suppress kernel-name space pollution unless user expressedly asks 119 for it. */ 120 #ifndef _LOOSE_KERNEL_NAMES 121 # define __KERNEL_STRICT_NAMES 122 #endif 123 124 /* Always use ISO C things. */ 125 #define __USE_ANSI 1 126 127 /* Convenience macros to test the versions of glibc and gcc. 128 Use them like this: 129 #if __GNUC_PREREQ (2,8) 130 ... code requiring gcc 2.8 or later ... 131 #endif 132 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 133 were not defined then. */ 134 #if defined __GNUC__ && defined __GNUC_MINOR__ 135 # define __GNUC_PREREQ(maj, min) \ 136 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 137 #else 138 # define __GNUC_PREREQ(maj, min) 0 139 #endif 140 141 142 /* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 143 #if defined _BSD_SOURCE && \ 144 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 145 defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \ 146 defined _GNU_SOURCE || defined _SVID_SOURCE) 147 # define __FAVOR_BSD 1 148 #endif 149 150 /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 151 #ifdef _GNU_SOURCE 152 # undef _ISOC99_SOURCE 153 # define _ISOC99_SOURCE 1 154 # undef _POSIX_SOURCE 155 # define _POSIX_SOURCE 1 156 # undef _POSIX_C_SOURCE 157 # define _POSIX_C_SOURCE 200809L 158 # undef _XOPEN_SOURCE 159 # define _XOPEN_SOURCE 700 160 # undef _XOPEN_SOURCE_EXTENDED 161 # define _XOPEN_SOURCE_EXTENDED 1 162 # undef _LARGEFILE64_SOURCE 163 # define _LARGEFILE64_SOURCE 1 164 # undef _BSD_SOURCE 165 # define _BSD_SOURCE 1 166 # undef _SVID_SOURCE 167 # define _SVID_SOURCE 1 168 # undef _ATFILE_SOURCE 169 # define _ATFILE_SOURCE 1 170 #endif 171 172 /* This macro indicates that the installed library is uClibc. Use 173 * __UCLIBC_MAJOR__ and __UCLIBC_MINOR__ to test for the features in 174 * specific releases. */ 175 #define __UCLIBC__ 1 176 177 #ifdef __UCLIBC__ 178 /* Load up the current set of uClibc supported features along 179 * with the current uClibc major and minor version numbers. 180 * For uClibc release 0.9.26, these numbers would be: 181 * #define __UCLIBC_MAJOR__ 0 182 * #define __UCLIBC_MINOR__ 9 183 * #define __UCLIBC_SUBLEVEL__ 26 184 */ 185 # define __need_uClibc_config_h 186 # include <bits/uClibc_config.h> 187 # undef __need_uClibc_config_h 188 189 /* For uClibc, always optimize for size -- this should disable 190 * a lot of expensive inlining... 191 * TODO: this is wrong! __OPTIMIZE_SIZE__ is an indicator of 192 * gcc -Os compile. We should not mess with compiler inlines. 193 * We should instead disable __USE_EXTERN_INLINES unconditionally, 194 * or maybe actually audit and test uclibc to work correctly 195 * with __USE_EXTERN_INLINES on. 196 */ 197 # define __OPTIMIZE_SIZE__ 1 198 199 /* disable unsupported features */ 200 # undef __LDBL_COMPAT 201 202 # ifndef __UCLIBC_HAS_FORTIFY__ 203 # undef _FORTIFY_SOURCE 204 # endif 205 206 # ifndef __UCLIBC_HAS_THREADS__ 207 # if defined _REENTRANT || defined _THREAD_SAFE 208 # warning requested reentrant code, but thread support was disabled 209 # undef _REENTRANT 210 # undef _THREAD_SAFE 211 # endif 212 # endif 213 214 # ifndef __UCLIBC_HAS_LFS__ 215 # undef _LARGEFILE64_SOURCE 216 /* NOTE: This is probably incorrect on a 64-bit arch... */ 217 # if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 218 # error It appears you have defined _FILE_OFFSET_BITS=64. Unfortunately, \ 219 uClibc was built without large file support enabled. 220 # endif 221 # elif defined __BCC__ 222 # error BCC does not support LFS, please disable it 223 # endif 224 #endif /* __UCLIBC__ */ 225 226 /* If nothing (other than _GNU_SOURCE) is defined, 227 define _BSD_SOURCE and _SVID_SOURCE. */ 228 #if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 229 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 230 !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \ 231 !defined _BSD_SOURCE && !defined _SVID_SOURCE) 232 # define _BSD_SOURCE 1 233 # define _SVID_SOURCE 1 234 #endif 235 236 /* This is to enable the ISO C99 extension. Also recognize the old macro 237 which was used prior to the standard acceptance. This macro will 238 eventually go away and the features enabled by default once the ISO C99 239 standard is widely adopted. */ 240 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 241 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 242 # define __USE_ISOC99 1 243 #endif 244 245 /* This is to enable the ISO C90 Amendment 1:1995 extension. */ 246 #if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 247 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 248 # define __USE_ISOC95 1 249 #endif 250 251 /* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 252 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 253 #if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 254 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 255 # define _POSIX_SOURCE 1 256 # if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 257 # define _POSIX_C_SOURCE 2 258 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 259 # define _POSIX_C_SOURCE 199506L 260 # elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 261 # define _POSIX_C_SOURCE 200112L 262 # else 263 # define _POSIX_C_SOURCE 200809L 264 # endif 265 # define __USE_POSIX_IMPLICITLY 1 266 #endif 267 268 #if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 269 # define __USE_POSIX 1 270 #endif 271 272 #if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 273 # define __USE_POSIX2 1 274 #endif 275 276 #if (_POSIX_C_SOURCE - 0) >= 199309L 277 # define __USE_POSIX199309 1 278 #endif 279 280 #if (_POSIX_C_SOURCE - 0) >= 199506L 281 # define __USE_POSIX199506 1 282 #endif 283 284 #if (_POSIX_C_SOURCE - 0) >= 200112L 285 # define __USE_XOPEN2K 1 286 # undef __USE_ISOC99 287 # define __USE_ISOC99 1 288 #endif 289 290 #if (_POSIX_C_SOURCE - 0) >= 200809L 291 # define __USE_XOPEN2K8 1 292 # undef _ATFILE_SOURCE 293 # define _ATFILE_SOURCE 1 294 #endif 295 296 #ifdef _XOPEN_SOURCE 297 # define __USE_XOPEN 1 298 # if (_XOPEN_SOURCE - 0) >= 500 299 # define __USE_XOPEN_EXTENDED 1 300 # define __USE_UNIX98 1 301 # undef _LARGEFILE_SOURCE 302 # define _LARGEFILE_SOURCE 1 303 # if (_XOPEN_SOURCE - 0) >= 600 304 # if (_XOPEN_SOURCE - 0) >= 700 305 # define __USE_XOPEN2K8 1 306 # endif 307 # define __USE_XOPEN2K 1 308 # undef __USE_ISOC99 309 # define __USE_ISOC99 1 310 # endif 311 # else 312 # ifdef _XOPEN_SOURCE_EXTENDED 313 # define __USE_XOPEN_EXTENDED 1 314 # endif 315 # endif 316 #endif 317 318 #ifdef _LARGEFILE_SOURCE 319 # define __USE_LARGEFILE 1 320 #endif 321 322 #ifdef _LARGEFILE64_SOURCE 323 # define __USE_LARGEFILE64 1 324 #endif 325 326 #if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 327 # define __USE_FILE_OFFSET64 1 328 #endif 329 330 #if defined _BSD_SOURCE || defined _SVID_SOURCE 331 # define __USE_MISC 1 332 #endif 333 334 #ifdef _BSD_SOURCE 335 # define __USE_BSD 1 336 #endif 337 338 #ifdef _SVID_SOURCE 339 # define __USE_SVID 1 340 #endif 341 342 #ifdef _ATFILE_SOURCE 343 # define __USE_ATFILE 1 344 #endif 345 346 #ifdef _GNU_SOURCE 347 # define __USE_GNU 1 348 #endif 349 350 #if defined _REENTRANT || defined _THREAD_SAFE 351 # define __USE_REENTRANT 1 352 #endif 353 354 #if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 355 && __GNUC_PREREQ (4, 1) && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 356 # if _FORTIFY_SOURCE > 1 357 # define __USE_FORTIFY_LEVEL 2 358 # else 359 # define __USE_FORTIFY_LEVEL 1 360 # endif 361 #else 362 # define __USE_FORTIFY_LEVEL 0 363 #endif 364 365 /* We do support the IEC 559 math functionality, real and complex. */ 366 #ifdef __UCLIBC_HAS_FLOATS__ 367 #define __STDC_IEC_559__ 1 368 #define __STDC_IEC_559_COMPLEX__ 1 369 #endif 370 371 #ifdef __UCLIBC_HAS_WCHAR__ 372 /* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 373 #define __STDC_ISO_10646__ 200009L 374 #endif 375 376 /* There is an unwholesomely huge amount of code out there that depends on the 377 * presence of GNU libc header files. We have GNU libc header files. So here 378 * we commit a horrible sin. At this point, we _lie_ and claim to be GNU libc 379 * to make things like /usr/include/linux/socket.h and lots of apps work as 380 * their developers intended. This is IMHO, pardonable, since these defines 381 * are not really intended to check for the presence of a particular library, 382 * but rather are used to define an _interface_. */ 383 #if !defined __FORCE_NOGLIBC && (!defined _LIBC || defined __FORCE_GLIBC) 384 /* This macro indicates that the installed library is the GNU C Library. 385 For historic reasons the value now is 6 and this will stay from now 386 on. The use of this variable is deprecated. */ 387 /* uClibc WARNING: leave these aligned to the left, don't put a space after '#', else 388 * broken apps could fail the check. */ 389 #undef __GNU_LIBRARY__ 390 #define __GNU_LIBRARY__ 6 391 392 /* Major and minor version number of the GNU C library package. Use 393 these macros to test for features in specific releases. */ 394 /* Don't do it, if you want to keep uClibc happy. */ 395 #define __GLIBC__ 2 396 #define __GLIBC_MINOR__ 2 397 #endif 398 399 #define __GLIBC_PREREQ(maj, min) \ 400 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 401 402 #ifndef __UCLIBC__ 403 /* Decide whether a compiler supports the long long datatypes. */ 404 #if defined __GNUC__ \ 405 || (defined __PGI && defined __i386__ ) \ 406 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 407 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 408 # define __GLIBC_HAVE_LONG_LONG 1 409 #endif 410 #endif 411 412 /* This is here only because every header file already includes this one. */ 413 #ifndef __ASSEMBLER__ 414 # ifndef _SYS_CDEFS_H 415 # include <sys/cdefs.h> 416 # endif 417 418 /* If we don't have __REDIRECT, prototypes will be missing if 419 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 420 # if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 421 # define __USE_LARGEFILE 1 422 # ifdef __UCLIBC_HAS_LFS__ 423 # define __USE_LARGEFILE64 1 424 # endif 425 # endif 426 427 #endif /* !ASSEMBLER */ 428 429 /* Decide whether we can, and are willing to define extern inline 430 * functions in headers, even if this results in a slightly bigger 431 * code for user programs built against uclibc. 432 * Enabled only in -O2 compiles, not -Os. 433 * uclibc itself is usually built without __USE_EXTERN_INLINES, 434 * remove "&& !defined __OPTIMIZE_SIZE__" part to do otherwise. 435 */ 436 #if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 437 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 438 && (defined __extern_inline || defined __GNUC_GNU_INLINE__ || defined __GNUC_STDC_INLINE__) 439 # define __USE_EXTERN_INLINES 1 440 #endif 441 442 #ifdef _LIBC 443 # ifdef __UCLIBC_HAS_LFS__ 444 # undef _FILE_OFFSET_BITS 445 # undef __USE_FILE_OFFSET64 446 # endif 447 # include <libc-internal.h> 448 #endif 449 450 #endif /* features.h */ 451