1 /* $OpenBSD: cdefs.h,v 1.39 2014/04/18 11:51:17 guenther Exp $ */ 2 /* $NetBSD: cdefs.h,v 1.16 1996/04/03 20:46:39 christos Exp $ */ 3 4 /* 5 * Copyright (c) 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Berkeley Software Design, Inc. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)cdefs.h 8.7 (Berkeley) 1/21/94 36 */ 37 38 #ifndef _SYS_CDEFS_H_ 39 #define _SYS_CDEFS_H_ 40 41 #include <machine/cdefs.h> 42 43 /* 44 * Macro to test if we're using a specific version of gcc or later. 45 */ 46 #ifdef __GNUC__ 47 #define __GNUC_PREREQ__(ma, mi) \ 48 ((__GNUC__ > (ma)) || (__GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))) 49 #else 50 #define __GNUC_PREREQ__(ma, mi) 0 51 #endif 52 53 /* 54 * The __CONCAT macro is used to concatenate parts of symbol names, e.g. 55 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo. 56 * The __CONCAT macro is a bit tricky -- make sure you don't put spaces 57 * in between its arguments. Do not use __CONCAT on double-quoted strings, 58 * such as those from the __STRING macro: to concatenate strings just put 59 * them next to each other. 60 */ 61 #if defined(__STDC__) || defined(__cplusplus) 62 #define __P(protos) protos /* full-blown ANSI C */ 63 #define __CONCAT(x,y) x ## y 64 #define __STRING(x) #x 65 66 #define __const const /* define reserved names to standard */ 67 #define __signed signed 68 #define __volatile volatile 69 #if defined(__cplusplus) || defined(__PCC__) 70 #define __inline inline /* convert to C++ keyword */ 71 #else 72 #if !defined(__GNUC__) 73 #define __inline /* delete GCC keyword */ 74 #endif /* !__GNUC__ */ 75 #endif /* !__cplusplus */ 76 77 #else /* !(__STDC__ || __cplusplus) */ 78 #define __P(protos) () /* traditional C preprocessor */ 79 #define __CONCAT(x,y) x/**/y 80 #define __STRING(x) "x" 81 82 #if !defined(__GNUC__) 83 #define __const /* delete pseudo-ANSI C keywords */ 84 #define __inline 85 #define __signed 86 #define __volatile 87 #endif /* !__GNUC__ */ 88 #endif /* !(__STDC__ || __cplusplus) */ 89 90 /* 91 * GCC1 and some versions of GCC2 declare dead (non-returning) and 92 * pure (no side effects) functions using "volatile" and "const"; 93 * unfortunately, these then cause warnings under "-ansi -pedantic". 94 * GCC >= 2.5 uses the __attribute__((attrs)) style. All of these 95 * work for GNU C++ (modulo a slight glitch in the C++ grammar in 96 * the distribution version of 2.5.5). 97 */ 98 99 #if !__GNUC_PREREQ__(2, 5) && !defined(__PCC__) 100 #define __attribute__(x) /* delete __attribute__ if non-gcc or gcc1 */ 101 #if defined(__GNUC__) && !defined(__STRICT_ANSI__) 102 #define __dead __volatile 103 #define __pure __const 104 #endif 105 #elif !defined(__STRICT_ANSI__) 106 #define __dead __attribute__((__noreturn__)) 107 #define __pure __attribute__((__const__)) 108 #endif 109 110 #if __GNUC_PREREQ__(2, 7) 111 #define __unused __attribute__((__unused__)) 112 #else 113 #define __unused /* delete */ 114 #endif 115 116 #if __GNUC_PREREQ__(3, 1) 117 #define __used __attribute__((__used__)) 118 #else 119 #define __used __unused /* suppress -Wunused warnings */ 120 #endif 121 122 #if __GNUC_PREREQ__(3,4) 123 # define __warn_unused_result __attribute__((__warn_unused_result__)) 124 #else 125 # define __warn_unused_result /* delete */ 126 #endif 127 128 #if __GNUC_PREREQ__(3,3) && !defined(__clang__) 129 # define __bounded(args) __attribute__ ((__bounded__ args )) 130 #else 131 # define __bounded(args) /* delete */ 132 #endif 133 134 /* 135 * __returns_twice makes the compiler not assume the function 136 * only returns once. This affects registerisation of variables: 137 * even local variables need to be in memory across such a call. 138 * Example: setjmp() 139 */ 140 #if __GNUC_PREREQ__(4, 1) 141 #define __returns_twice __attribute__((returns_twice)) 142 #else 143 #define __returns_twice 144 #endif 145 146 /* 147 * __only_inline makes the compiler only use this function definition 148 * for inlining; references that can't be inlined will be left as 149 * external references instead of generating a local copy. The 150 * matching library should include a simple extern definition for 151 * the function to handle those references. c.f. ctype.h 152 */ 153 #ifdef __GNUC__ 154 # if __GNUC_PREREQ__(4, 2) 155 #define __only_inline extern __inline __attribute__((__gnu_inline__)) 156 # else 157 #define __only_inline extern __inline 158 # endif 159 #else 160 #define __only_inline static __inline 161 #endif 162 163 /* 164 * GNU C version 2.96 adds explicit branch prediction so that 165 * the CPU back-end can hint the processor and also so that 166 * code blocks can be reordered such that the predicted path 167 * sees a more linear flow, thus improving cache behavior, etc. 168 * 169 * The following two macros provide us with a way to utilize this 170 * compiler feature. Use __predict_true() if you expect the expression 171 * to evaluate to true, and __predict_false() if you expect the 172 * expression to evaluate to false. 173 * 174 * A few notes about usage: 175 * 176 * * Generally, __predict_false() error condition checks (unless 177 * you have some _strong_ reason to do otherwise, in which case 178 * document it), and/or __predict_true() `no-error' condition 179 * checks, assuming you want to optimize for the no-error case. 180 * 181 * * Other than that, if you don't know the likelihood of a test 182 * succeeding from empirical or other `hard' evidence, don't 183 * make predictions. 184 * 185 * * These are meant to be used in places that are run `a lot'. 186 * It is wasteful to make predictions in code that is run 187 * seldomly (e.g. at subsystem initialization time) as the 188 * basic block reordering that this affects can often generate 189 * larger code. 190 */ 191 #if __GNUC_PREREQ__(2, 96) 192 #define __predict_true(exp) __builtin_expect(((exp) != 0), 1) 193 #define __predict_false(exp) __builtin_expect(((exp) != 0), 0) 194 #else 195 #define __predict_true(exp) ((exp) != 0) 196 #define __predict_false(exp) ((exp) != 0) 197 #endif 198 199 /* Delete pseudo-keywords wherever they are not available or needed. */ 200 #ifndef __dead 201 #define __dead 202 #define __pure 203 #endif 204 205 /* 206 * The __packed macro indicates that a variable or structure members 207 * should have the smallest possible alignment, despite any host CPU 208 * alignment requirements. 209 * 210 * The __aligned(x) macro specifies the minimum alignment of a 211 * variable or structure. 212 * 213 * These macros together are useful for describing the layout and 214 * alignment of messages exchanged with hardware or other systems. 215 */ 216 217 #if __GNUC_PREREQ__(2, 7) || defined(__PCC__) 218 #define __packed __attribute__((__packed__)) 219 #define __aligned(x) __attribute__((__aligned__(x))) 220 #endif 221 222 #if !__GNUC_PREREQ__(2, 8) 223 #define __extension__ 224 #endif 225 226 #if __GNUC_PREREQ__(2, 8) || defined(__PCC__) 227 #define __statement(x) __extension__(x) 228 #else 229 #define __statement(x) (x) 230 #endif 231 232 #if __GNUC_PREREQ__(3, 0) 233 #define __malloc __attribute__((__malloc__)) 234 #else 235 #define __malloc 236 #endif 237 238 #if defined(__cplusplus) 239 #define __BEGIN_EXTERN_C extern "C" { 240 #define __END_EXTERN_C } 241 #else 242 #define __BEGIN_EXTERN_C 243 #define __END_EXTERN_C 244 #endif 245 246 #if __GNUC_PREREQ__(4, 0) 247 #define __dso_public __attribute__((__visibility__("default"))) 248 #define __dso_hidden __attribute__((__visibility__("hidden"))) 249 #define __BEGIN_PUBLIC_DECLS \ 250 _Pragma("GCC visibility push(default)") __BEGIN_EXTERN_C 251 #define __END_PUBLIC_DECLS __END_EXTERN_C _Pragma("GCC visibility pop") 252 #define __BEGIN_HIDDEN_DECLS \ 253 _Pragma("GCC visibility push(hidden)") __BEGIN_EXTERN_C 254 #define __END_HIDDEN_DECLS __END_EXTERN_C _Pragma("GCC visibility pop") 255 #else 256 #define __dso_public 257 #define __dso_hidden 258 #define __BEGIN_PUBLIC_DECLS __BEGIN_EXTERN_C 259 #define __END_PUBLIC_DECLS __END_EXTERN_C 260 #define __BEGIN_HIDDEN_DECLS __BEGIN_EXTERN_C 261 #define __END_HIDDEN_DECLS __END_EXTERN_C 262 #endif 263 264 #define __BEGIN_DECLS __BEGIN_EXTERN_C 265 #define __END_DECLS __END_EXTERN_C 266 267 /* 268 * "The nice thing about standards is that there are so many to choose from." 269 * There are a number of "feature test macros" specified by (different) 270 * standards that determine which interfaces and types the header files 271 * should expose. 272 * 273 * Because of inconsistencies in these macros, we define our own 274 * set in the private name space that end in _VISIBLE. These are 275 * always defined and so headers can test their values easily. 276 * Things can get tricky when multiple feature macros are defined. 277 * We try to take the union of all the features requested. 278 * 279 * The following macros are guaranteed to have a value after cdefs.h 280 * has been included: 281 * __POSIX_VISIBLE 282 * __XPG_VISIBLE 283 * __ISO_C_VISIBLE 284 * __BSD_VISIBLE 285 */ 286 287 /* 288 * X/Open Portability Guides and Single Unix Specifications. 289 * _XOPEN_SOURCE XPG3 290 * _XOPEN_SOURCE && _XOPEN_VERSION = 4 XPG4 291 * _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED = 1 XPG4v2 292 * _XOPEN_SOURCE == 500 XPG5 293 * _XOPEN_SOURCE == 520 XPG5v2 294 * _XOPEN_SOURCE == 600 POSIX 1003.1-2001 with XSI 295 * _XOPEN_SOURCE == 700 POSIX 1003.1-2008 with XSI 296 * 297 * The XPG spec implies a specific value for _POSIX_C_SOURCE. 298 */ 299 #ifdef _XOPEN_SOURCE 300 # if (_XOPEN_SOURCE - 0 >= 700) 301 # define __XPG_VISIBLE 700 302 # undef _POSIX_C_SOURCE 303 # define _POSIX_C_SOURCE 200809L 304 # elif (_XOPEN_SOURCE - 0 >= 600) 305 # define __XPG_VISIBLE 600 306 # undef _POSIX_C_SOURCE 307 # define _POSIX_C_SOURCE 200112L 308 # elif (_XOPEN_SOURCE - 0 >= 520) 309 # define __XPG_VISIBLE 520 310 # undef _POSIX_C_SOURCE 311 # define _POSIX_C_SOURCE 199506L 312 # elif (_XOPEN_SOURCE - 0 >= 500) 313 # define __XPG_VISIBLE 500 314 # undef _POSIX_C_SOURCE 315 # define _POSIX_C_SOURCE 199506L 316 # elif (_XOPEN_SOURCE_EXTENDED - 0 == 1) 317 # define __XPG_VISIBLE 420 318 # elif (_XOPEN_VERSION - 0 >= 4) 319 # define __XPG_VISIBLE 400 320 # else 321 # define __XPG_VISIBLE 300 322 # endif 323 #endif 324 325 /* 326 * POSIX macros, these checks must follow the XOPEN ones above. 327 * 328 * _POSIX_SOURCE == 1 1003.1-1988 (superseded by _POSIX_C_SOURCE) 329 * _POSIX_C_SOURCE == 1 1003.1-1990 330 * _POSIX_C_SOURCE == 2 1003.2-1992 331 * _POSIX_C_SOURCE == 199309L 1003.1b-1993 332 * _POSIX_C_SOURCE == 199506L 1003.1c-1995, 1003.1i-1995, 333 * and the omnibus ISO/IEC 9945-1:1996 334 * _POSIX_C_SOURCE == 200112L 1003.1-2001 335 * _POSIX_C_SOURCE == 200809L 1003.1-2008 336 * 337 * The POSIX spec implies a specific value for __ISO_C_VISIBLE, though 338 * this may be overridden by the _ISOC99_SOURCE macro later. 339 */ 340 #ifdef _POSIX_C_SOURCE 341 # if (_POSIX_C_SOURCE - 0 >= 200809) 342 # define __POSIX_VISIBLE 200809 343 # define __ISO_C_VISIBLE 1999 344 # elif (_POSIX_C_SOURCE - 0 >= 200112) 345 # define __POSIX_VISIBLE 200112 346 # define __ISO_C_VISIBLE 1999 347 # elif (_POSIX_C_SOURCE - 0 >= 199506) 348 # define __POSIX_VISIBLE 199506 349 # define __ISO_C_VISIBLE 1990 350 # elif (_POSIX_C_SOURCE - 0 >= 199309) 351 # define __POSIX_VISIBLE 199309 352 # define __ISO_C_VISIBLE 1990 353 # elif (_POSIX_C_SOURCE - 0 >= 2) 354 # define __POSIX_VISIBLE 199209 355 # define __ISO_C_VISIBLE 1990 356 # else 357 # define __POSIX_VISIBLE 199009 358 # define __ISO_C_VISIBLE 1990 359 # endif 360 #elif defined(_POSIX_SOURCE) 361 # define __POSIX_VISIBLE 198808 362 # define __ISO_C_VISIBLE 0 363 #endif 364 365 /* 366 * _ANSI_SOURCE means to expose ANSI C89 interfaces only. 367 * If the user defines it in addition to one of the POSIX or XOPEN 368 * macros, assume the POSIX/XOPEN macro(s) should take precedence. 369 */ 370 #if defined(_ANSI_SOURCE) && !defined(__POSIX_VISIBLE) && \ 371 !defined(__XPG_VISIBLE) 372 # define __POSIX_VISIBLE 0 373 # define __XPG_VISIBLE 0 374 # define __ISO_C_VISIBLE 1990 375 #endif 376 377 /* 378 * _ISOC99_SOURCE and __STDC_VERSION__ override any of the other macros since 379 * they are non-exclusive. 380 */ 381 #if defined(_ISOC99_SOURCE) || \ 382 (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901) || \ 383 (defined(__cplusplus) && __cplusplus >= 201103) 384 # undef __ISO_C_VISIBLE 385 # define __ISO_C_VISIBLE 1999 386 #endif 387 388 /* 389 * Finally deal with BSD-specific interfaces that are not covered 390 * by any standards. We expose these when none of the POSIX or XPG 391 * macros is defined or if the user explicitly asks for them. 392 */ 393 #if !defined(_BSD_SOURCE) && \ 394 (defined(_ANSI_SOURCE) || defined(__XPG_VISIBLE) || defined(__POSIX_VISIBLE)) 395 # define __BSD_VISIBLE 0 396 #endif 397 398 /* 399 * Default values. 400 */ 401 #ifndef __XPG_VISIBLE 402 # define __XPG_VISIBLE 700 403 #endif 404 #ifndef __POSIX_VISIBLE 405 # define __POSIX_VISIBLE 200809 406 #endif 407 #ifndef __ISO_C_VISIBLE 408 # define __ISO_C_VISIBLE 1999 409 #endif 410 #ifndef __BSD_VISIBLE 411 # define __BSD_VISIBLE 1 412 #endif 413 414 #endif /* !_SYS_CDEFS_H_ */ 415