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, 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_XOPEN2K8 Define XPG7 things. 70 __USE_LARGEFILE Define correct standard I/O things. 71 __USE_LARGEFILE64 Define LFS things with separate names. 72 __USE_FILE_OFFSET64 Define 64bit interface as default. 73 __USE_BSD Define 4.3BSD things. 74 __USE_SVID Define SVID things. 75 __USE_MISC Define things common to BSD and System V Unix. 76 __USE_ATFILE Define *at interfaces and AT_* constants for them. 77 __USE_GNU Define GNU extensions. 78 __USE_REENTRANT Define reentrant/thread-safe *_r functions. 79 __USE_FORTIFY_LEVEL Additional security measures used, according to level. 80 __FAVOR_BSD Favor 4.3BSD things in cases of conflict. 81 82 The macros `__GNU_LIBRARY__', `__GLIBC__', and `__GLIBC_MINOR__' are 83 defined by this file unconditionally. `__GNU_LIBRARY__' is provided 84 only for compatibility. All new code should use the other symbols 85 to test for features. 86 87 All macros listed above as possibly being defined by this file are 88 explicitly undefined if they are not explicitly defined. 89 Feature-test macros that are not defined by the user or compiler 90 but are implied by the other feature-test macros defined (or by the 91 lack of any definitions) are defined by the file. */ 92 93 94/* Undefine everything, so we get a clean slate. */ 95#undef __USE_ISOC99 96#undef __USE_ISOC95 97#undef __USE_POSIX 98#undef __USE_POSIX2 99#undef __USE_POSIX199309 100#undef __USE_POSIX199506 101#undef __USE_XOPEN 102#undef __USE_XOPEN_EXTENDED 103#undef __USE_UNIX98 104#undef __USE_XOPEN2K 105#undef __USE_XOPEN2K8 106#undef __USE_LARGEFILE 107#undef __USE_LARGEFILE64 108#undef __USE_FILE_OFFSET64 109#undef __USE_BSD 110#undef __USE_SVID 111#undef __USE_MISC 112#undef __USE_ATFILE 113#undef __USE_GNU 114#undef __USE_REENTRANT 115#undef __USE_FORTIFY_LEVEL 116#undef __FAVOR_BSD 117#undef __KERNEL_STRICT_NAMES 118 119/* Suppress kernel-name space pollution unless user expressedly asks 120 for it. */ 121#ifndef _LOOSE_KERNEL_NAMES 122# define __KERNEL_STRICT_NAMES 123#endif 124 125/* Always use ISO C things. */ 126#define __USE_ANSI 1 127 128/* Convenience macros to test the versions of glibc and gcc. 129 Use them like this: 130 #if __GNUC_PREREQ (2,8) 131 ... code requiring gcc 2.8 or later ... 132 #endif 133 Note - they won't work for gcc1 or glibc1, since the _MINOR macros 134 were not defined then. */ 135#if defined __GNUC__ && defined __GNUC_MINOR__ 136# define __GNUC_PREREQ(maj, min) \ 137 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) 138#else 139# define __GNUC_PREREQ(maj, min) 0 140#endif 141 142 143/* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ 144#if defined _BSD_SOURCE && \ 145 !(defined _POSIX_SOURCE || defined _POSIX_C_SOURCE || \ 146 defined _XOPEN_SOURCE || defined _XOPEN_SOURCE_EXTENDED || \ 147 defined _GNU_SOURCE || defined _SVID_SOURCE) 148# define __FAVOR_BSD 1 149#endif 150 151/* If _GNU_SOURCE was defined by the user, turn on all the other features. */ 152#ifdef _GNU_SOURCE 153# undef _ISOC99_SOURCE 154# define _ISOC99_SOURCE 1 155# undef _POSIX_SOURCE 156# define _POSIX_SOURCE 1 157# undef _POSIX_C_SOURCE 158# define _POSIX_C_SOURCE 200809L 159# undef _XOPEN_SOURCE 160# define _XOPEN_SOURCE 700 161# undef _XOPEN_SOURCE_EXTENDED 162# define _XOPEN_SOURCE_EXTENDED 1 163# undef _LARGEFILE64_SOURCE 164# define _LARGEFILE64_SOURCE 1 165# undef _BSD_SOURCE 166# define _BSD_SOURCE 1 167# undef _SVID_SOURCE 168# define _SVID_SOURCE 1 169# undef _ATFILE_SOURCE 170# define _ATFILE_SOURCE 1 171#endif 172 173/* If nothing (other than _GNU_SOURCE) is defined, 174 define _BSD_SOURCE and _SVID_SOURCE. */ 175#if (!defined __STRICT_ANSI__ && !defined _ISOC99_SOURCE && \ 176 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE && \ 177 !defined _XOPEN_SOURCE && !defined _XOPEN_SOURCE_EXTENDED && \ 178 !defined _BSD_SOURCE && !defined _SVID_SOURCE) 179# define _BSD_SOURCE 1 180# define _SVID_SOURCE 1 181#endif 182 183/* This is to enable the ISO C99 extension. Also recognize the old macro 184 which was used prior to the standard acceptance. This macro will 185 eventually go away and the features enabled by default once the ISO C99 186 standard is widely adopted. */ 187#if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 188 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)) 189# define __USE_ISOC99 1 190#endif 191 192/* This is to enable the ISO C90 Amendment 1:1995 extension. */ 193#if (defined _ISOC99_SOURCE || defined _ISOC9X_SOURCE \ 194 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199409L)) 195# define __USE_ISOC95 1 196#endif 197 198/* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2 199 (and IEEE Std 1003.1b-1993 unless _XOPEN_SOURCE is defined). */ 200#if ((!defined __STRICT_ANSI__ || (_XOPEN_SOURCE - 0) >= 500) && \ 201 !defined _POSIX_SOURCE && !defined _POSIX_C_SOURCE) 202# define _POSIX_SOURCE 1 203# if defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 500 204# define _POSIX_C_SOURCE 2 205# elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 600 206# define _POSIX_C_SOURCE 199506L 207# elif defined _XOPEN_SOURCE && (_XOPEN_SOURCE - 0) < 700 208# define _POSIX_C_SOURCE 200112L 209# else 210# define _POSIX_C_SOURCE 200809L 211# endif 212# define __USE_POSIX_IMPLICITLY 1 213#endif 214 215#if defined _POSIX_SOURCE || _POSIX_C_SOURCE >= 1 || defined _XOPEN_SOURCE 216# define __USE_POSIX 1 217#endif 218 219#if defined _POSIX_C_SOURCE && _POSIX_C_SOURCE >= 2 || defined _XOPEN_SOURCE 220# define __USE_POSIX2 1 221#endif 222 223#if (_POSIX_C_SOURCE - 0) >= 199309L 224# define __USE_POSIX199309 1 225#endif 226 227#if (_POSIX_C_SOURCE - 0) >= 199506L 228# define __USE_POSIX199506 1 229#endif 230 231#if (_POSIX_C_SOURCE - 0) >= 200112L 232# define __USE_XOPEN2K 1 233# undef __USE_ISOC99 234# define __USE_ISOC99 1 235#endif 236 237#if (_POSIX_C_SOURCE - 0) >= 200809L 238# define __USE_XOPEN2K8 1 239# undef _ATFILE_SOURCE 240# define _ATFILE_SOURCE 1 241#endif 242 243#ifdef _XOPEN_SOURCE 244# define __USE_XOPEN 1 245# if (_XOPEN_SOURCE - 0) >= 500 246# define __USE_XOPEN_EXTENDED 1 247# define __USE_UNIX98 1 248# undef _LARGEFILE_SOURCE 249# define _LARGEFILE_SOURCE 1 250# if (_XOPEN_SOURCE - 0) >= 600 251# if (_XOPEN_SOURCE - 0) >= 700 252# define __USE_XOPEN2K8 1 253# endif 254# define __USE_XOPEN2K 1 255# undef __USE_ISOC99 256# define __USE_ISOC99 1 257# endif 258# else 259# ifdef _XOPEN_SOURCE_EXTENDED 260# define __USE_XOPEN_EXTENDED 1 261# endif 262# endif 263#endif 264 265#ifdef _LARGEFILE_SOURCE 266# define __USE_LARGEFILE 1 267#endif 268 269#ifdef _LARGEFILE64_SOURCE 270# define __USE_LARGEFILE64 1 271#endif 272 273#if defined _FILE_OFFSET_BITS && _FILE_OFFSET_BITS == 64 274# define __USE_FILE_OFFSET64 1 275#endif 276 277#if defined _BSD_SOURCE || defined _SVID_SOURCE 278# define __USE_MISC 1 279#endif 280 281#ifdef _BSD_SOURCE 282# define __USE_BSD 1 283#endif 284 285#ifdef _SVID_SOURCE 286# define __USE_SVID 1 287#endif 288 289#ifdef _ATFILE_SOURCE 290# define __USE_ATFILE 1 291#endif 292 293#ifdef _GNU_SOURCE 294# define __USE_GNU 1 295#endif 296 297#if defined _REENTRANT || defined _THREAD_SAFE 298# define __USE_REENTRANT 1 299#endif 300 301#if defined _FORTIFY_SOURCE && _FORTIFY_SOURCE > 0 \ 302 && __GNUC_PREREQ (4, 1) && defined __OPTIMIZE__ && __OPTIMIZE__ > 0 303# if _FORTIFY_SOURCE > 1 304# define __USE_FORTIFY_LEVEL 2 305# else 306# define __USE_FORTIFY_LEVEL 1 307# endif 308#else 309# define __USE_FORTIFY_LEVEL 0 310#endif 311 312/* Define __STDC_IEC_559__ and other similar macros. */ 313#include <bits/predefs.h> 314 315/* wchar_t uses ISO 10646-1 (2nd ed., published 2000-09-15) / Unicode 3.1. */ 316#define __STDC_ISO_10646__ 200009L 317 318/* This macro indicates that the installed library is the GNU C Library. 319 For historic reasons the value now is 6 and this will stay from now 320 on. The use of this variable is deprecated. Use __GLIBC__ and 321 __GLIBC_MINOR__ now (see below) when you want to test for a specific 322 GNU C library version and use the values in <gnu/lib-names.h> to get 323 the sonames of the shared libraries. */ 324#undef __GNU_LIBRARY__ 325#define __GNU_LIBRARY__ 6 326 327/* Major and minor version number of the GNU C library package. Use 328 these macros to test for features in specific releases. */ 329#define __GLIBC__ 2 330#define __GLIBC_MINOR__ 11 331 332#define __GLIBC_PREREQ(maj, min) \ 333 ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min)) 334 335/* Decide whether a compiler supports the long long datatypes. */ 336#if defined __GNUC__ \ 337 || (defined __PGI && defined __i386__ ) \ 338 || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \ 339 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L) 340# define __GLIBC_HAVE_LONG_LONG 1 341#endif 342 343/* This is here only because every header file already includes this one. */ 344#ifndef __ASSEMBLER__ 345# ifndef _SYS_CDEFS_H 346# include <sys/cdefs.h> 347# endif 348 349/* If we don't have __REDIRECT, prototypes will be missing if 350 __USE_FILE_OFFSET64 but not __USE_LARGEFILE[64]. */ 351# if defined __USE_FILE_OFFSET64 && !defined __REDIRECT 352# define __USE_LARGEFILE 1 353# define __USE_LARGEFILE64 1 354# endif 355 356#endif /* !ASSEMBLER */ 357 358/* Decide whether we can define 'extern inline' functions in headers. */ 359#if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 360 && !defined __OPTIMIZE_SIZE__ && !defined __NO_INLINE__ \ 361 && defined __extern_inline 362# define __USE_EXTERN_INLINES 1 363#endif 364 365/* There are some functions that must be declared 'extern inline' even with 366 -Os when building LIBC, or they'll end up undefined. */ 367#if __GNUC_PREREQ (2, 7) && defined __OPTIMIZE__ \ 368 && (defined _LIBC || !defined __OPTIMIZE_SIZE__) && !defined __NO_INLINE__ \ 369 && defined __extern_inline 370# define __USE_EXTERN_INLINES_IN_LIBC 1 371#endif 372 373 374/* This is here only because every header file already includes this one. 375 Get the definitions of all the appropriate `__stub_FUNCTION' symbols. 376 <gnu/stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub 377 that will always return failure (and set errno to ENOSYS). */ 378#include <gnu/stubs.h> 379 380 381#endif /* features.h */ 382