1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95 35 */ 36 37 #ifndef _SYS_CDEFS_H_ 38 #define _SYS_CDEFS_H_ 39 40 #if defined(_KERNEL) && defined(_STANDALONE) 41 #error "_KERNEL and _STANDALONE are mutually exclusive" 42 #endif 43 44 /* 45 * Testing against Clang-specific extensions. 46 */ 47 #ifndef __has_attribute 48 #define __has_attribute(x) 0 49 #endif 50 #ifndef __has_extension 51 #define __has_extension __has_feature 52 #endif 53 #ifndef __has_feature 54 #define __has_feature(x) 0 55 #endif 56 #ifndef __has_include 57 #define __has_include(x) 0 58 #endif 59 #ifndef __has_builtin 60 #define __has_builtin(x) 0 61 #endif 62 63 #if defined(__cplusplus) 64 #define __BEGIN_DECLS extern "C" { 65 #define __END_DECLS } 66 #else 67 #define __BEGIN_DECLS 68 #define __END_DECLS 69 #endif 70 71 /* 72 * This code has been put in place to help reduce the addition of 73 * compiler specific defines in FreeBSD code. It helps to aid in 74 * having a compiler-agnostic source tree. 75 */ 76 77 #if defined(__GNUC__) 78 79 #if __GNUC__ >= 3 80 #define __GNUCLIKE_ASM 3 81 #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS 82 #else 83 #define __GNUCLIKE_ASM 2 84 #endif 85 #define __GNUCLIKE___TYPEOF 1 86 #define __GNUCLIKE___SECTION 1 87 88 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1 89 90 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1 91 92 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3) 93 #define __GNUCLIKE_BUILTIN_VARARGS 1 94 #define __GNUCLIKE_BUILTIN_STDARG 1 95 #define __GNUCLIKE_BUILTIN_VAALIST 1 96 #endif 97 98 #define __GNUC_VA_LIST_COMPATIBILITY 1 99 100 /* 101 * Compiler memory barriers, specific to gcc and clang. 102 */ 103 #define __compiler_membar() __asm __volatile(" " : : : "memory") 104 105 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1 106 #define __GNUCLIKE_MATH_BUILTIN_RELOPS 107 108 #define __GNUCLIKE_BUILTIN_MEMCPY 1 109 110 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */ 111 #define __CC_SUPPORTS_INLINE 1 112 #define __CC_SUPPORTS___INLINE 1 113 #define __CC_SUPPORTS___INLINE__ 1 114 115 #define __CC_SUPPORTS___FUNC__ 1 116 #define __CC_SUPPORTS_WARNING 1 117 118 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */ 119 120 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1 121 122 #endif /* __GNUC__ */ 123 124 /* 125 * Macro to test if we're using a specific version of gcc or later. 126 */ 127 #if defined(__GNUC__) 128 #define __GNUC_PREREQ__(ma, mi) \ 129 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi)) 130 #else 131 #define __GNUC_PREREQ__(ma, mi) 0 132 #endif 133 134 /* 135 * The __CONCAT macro is used to concatenate parts of symbol names, e.g. 136 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo. 137 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI 138 * mode -- there must be no spaces between its arguments, and for nested 139 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also 140 * concatenate double-quoted strings produced by the __STRING macro, but 141 * this only works with ANSI C. 142 * 143 * __XSTRING is like __STRING, but it expands any macros in its argument 144 * first. It is only available with ANSI C. 145 */ 146 #if defined(__STDC__) || defined(__cplusplus) 147 #define __P(protos) protos /* full-blown ANSI C */ 148 #define __CONCAT1(x,y) x ## y 149 #define __CONCAT(x,y) __CONCAT1(x,y) 150 #define __STRING(x) #x /* stringify without expanding x */ 151 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */ 152 153 #define __const const /* define reserved names to standard */ 154 #define __signed signed 155 #define __volatile volatile 156 #if defined(__cplusplus) 157 #define __inline inline /* convert to C++ keyword */ 158 #else 159 #if !(defined(__CC_SUPPORTS___INLINE)) 160 #define __inline /* delete GCC keyword */ 161 #endif /* ! __CC_SUPPORTS___INLINE */ 162 #endif /* !__cplusplus */ 163 164 #else /* !(__STDC__ || __cplusplus) */ 165 #define __P(protos) () /* traditional C preprocessor */ 166 #define __CONCAT(x,y) x/**/y 167 #define __STRING(x) "x" 168 169 #if !defined(__CC_SUPPORTS___INLINE) 170 #define __const /* delete pseudo-ANSI C keywords */ 171 #define __inline 172 #define __signed 173 #define __volatile 174 /* 175 * In non-ANSI C environments, new programs will want ANSI-only C keywords 176 * deleted from the program and old programs will want them left alone. 177 * When using a compiler other than gcc, programs using the ANSI C keywords 178 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS. 179 * When using "gcc -traditional", we assume that this is the intent; if 180 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone. 181 */ 182 #ifndef NO_ANSI_KEYWORDS 183 #define const /* delete ANSI C keywords */ 184 #define inline 185 #define signed 186 #define volatile 187 #endif /* !NO_ANSI_KEYWORDS */ 188 #endif /* !__CC_SUPPORTS___INLINE */ 189 #endif /* !(__STDC__ || __cplusplus) */ 190 191 /* 192 * Compiler-dependent macros to help declare dead (non-returning) and 193 * pure (no side effects) functions, and unused variables. They are 194 * null except for versions of gcc that are known to support the features 195 * properly (old versions of gcc-2 supported the dead and pure features 196 * in a different (wrong) way). If we do not provide an implementation 197 * for a given compiler, let the compile fail if it is told to use 198 * a feature that we cannot live without. 199 */ 200 #define __weak_symbol __attribute__((__weak__)) 201 #if !__GNUC_PREREQ__(2, 5) 202 #define __dead2 203 #define __pure2 204 #define __unused 205 #endif 206 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 207 #define __dead2 __attribute__((__noreturn__)) 208 #define __pure2 __attribute__((__const__)) 209 #define __unused 210 /* XXX Find out what to do for __packed, __aligned and __section */ 211 #endif 212 #if __GNUC_PREREQ__(2, 7) 213 #define __dead2 __attribute__((__noreturn__)) 214 #define __pure2 __attribute__((__const__)) 215 #define __unused __attribute__((__unused__)) 216 #define __used __attribute__((__used__)) 217 #define __packed __attribute__((__packed__)) 218 #define __aligned(x) __attribute__((__aligned__(x))) 219 #define __section(x) __attribute__((__section__(x))) 220 #endif 221 #define __writeonly __unused 222 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__) 223 #define __alloc_size(x) __attribute__((__alloc_size__(x))) 224 #define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x))) 225 #else 226 #define __alloc_size(x) 227 #define __alloc_size2(n, x) 228 #endif 229 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__) 230 #define __alloc_align(x) __attribute__((__alloc_align__(x))) 231 #else 232 #define __alloc_align(x) 233 #endif 234 235 #if !__GNUC_PREREQ__(2, 95) 236 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b) 237 #endif 238 239 /* 240 * Keywords added in C11. 241 */ 242 243 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L 244 245 #if !__has_extension(c_alignas) 246 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ 247 __has_extension(cxx_alignas) 248 #define _Alignas(x) alignas(x) 249 #else 250 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */ 251 #define _Alignas(x) __aligned(x) 252 #endif 253 #endif 254 255 #if defined(__cplusplus) && __cplusplus >= 201103L 256 #define _Alignof(x) alignof(x) 257 #else 258 #define _Alignof(x) __alignof(x) 259 #endif 260 261 #if !defined(__cplusplus) && !__has_extension(c_atomic) && \ 262 !__has_extension(cxx_atomic) && !__GNUC_PREREQ__(4, 7) 263 /* 264 * No native support for _Atomic(). Place object in structure to prevent 265 * most forms of direct non-atomic access. 266 */ 267 #define _Atomic(T) struct { T volatile __val; } 268 #endif 269 270 #if defined(__cplusplus) && __cplusplus >= 201103L 271 #define _Noreturn [[noreturn]] 272 #else 273 #define _Noreturn __dead2 274 #endif 275 276 #if !__has_extension(c_static_assert) 277 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ 278 __has_extension(cxx_static_assert) 279 #define _Static_assert(x, y) static_assert(x, y) 280 #endif 281 #endif 282 283 #if !__has_extension(c_thread_local) 284 /* 285 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode 286 * without actually supporting the thread_local keyword. Don't check for 287 * the presence of C++11 when defining _Thread_local. 288 */ 289 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \ 290 __has_extension(cxx_thread_local) 291 #define _Thread_local thread_local 292 #else 293 #define _Thread_local __thread 294 #endif 295 #endif 296 297 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */ 298 299 /* 300 * Emulation of C11 _Generic(). Unlike the previously defined C11 301 * keywords, it is not possible to implement this using exactly the same 302 * syntax. Therefore implement something similar under the name 303 * __generic(). Unlike _Generic(), this macro can only distinguish 304 * between a single type, so it requires nested invocations to 305 * distinguish multiple cases. 306 * 307 * Note that the comma operator is used to force expr to decay in 308 * order to match _Generic(). 309 */ 310 311 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \ 312 __has_extension(c_generic_selections) 313 #define __generic(expr, t, yes, no) \ 314 _Generic(expr, t: yes, default: no) 315 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus) 316 #define __generic(expr, t, yes, no) \ 317 __builtin_choose_expr( \ 318 __builtin_types_compatible_p(__typeof((0, (expr))), t), yes, no) 319 #endif 320 321 /* 322 * C99 Static array indices in function parameter declarations. Syntax such as: 323 * void bar(int myArray[static 10]); 324 * is allowed in C99 but not in C++. Define __min_size appropriately so 325 * headers using it can be compiled in either language. Use like this: 326 * void bar(int myArray[__min_size(10)]); 327 */ 328 #if !defined(__cplusplus) && \ 329 (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \ 330 (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901)) 331 #define __min_size(x) static (x) 332 #else 333 #define __min_size(x) (x) 334 #endif 335 336 #if __GNUC_PREREQ__(2, 96) 337 #define __malloc_like __attribute__((__malloc__)) 338 #define __pure __attribute__((__pure__)) 339 #else 340 #define __malloc_like 341 #define __pure 342 #endif 343 344 #if __GNUC_PREREQ__(3, 1) 345 #define __always_inline __attribute__((__always_inline__)) 346 #else 347 #define __always_inline 348 #endif 349 350 #if __GNUC_PREREQ__(3, 1) 351 #define __noinline __attribute__ ((__noinline__)) 352 #else 353 #define __noinline 354 #endif 355 356 #if __GNUC_PREREQ__(3, 4) 357 #define __fastcall __attribute__((__fastcall__)) 358 #define __result_use_check __attribute__((__warn_unused_result__)) 359 #else 360 #define __fastcall 361 #define __result_use_check 362 #endif 363 364 #if __GNUC_PREREQ__(4, 1) 365 #define __returns_twice __attribute__((__returns_twice__)) 366 #else 367 #define __returns_twice 368 #endif 369 370 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable) 371 #define __unreachable() __builtin_unreachable() 372 #else 373 #define __unreachable() ((void)0) 374 #endif 375 376 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */ 377 #if !__GNUC_PREREQ__(2, 7) 378 #define __func__ NULL 379 #endif 380 381 #if (defined(__GNUC__) && __GNUC__ >= 2) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901 382 #define __LONG_LONG_SUPPORTED 383 #endif 384 385 /* C++11 exposes a load of C99 stuff */ 386 #if defined(__cplusplus) && __cplusplus >= 201103L 387 #define __LONG_LONG_SUPPORTED 388 #ifndef __STDC_LIMIT_MACROS 389 #define __STDC_LIMIT_MACROS 390 #endif 391 #ifndef __STDC_CONSTANT_MACROS 392 #define __STDC_CONSTANT_MACROS 393 #endif 394 #endif 395 396 /* 397 * We use `__restrict' as a way to define the `restrict' type qualifier 398 * without disturbing older software that is unaware of C99 keywords. 399 * GCC also provides `__restrict' as an extension to support C99-style 400 * restricted pointers in other language modes. 401 */ 402 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901 403 #define __restrict restrict 404 #elif !__GNUC_PREREQ__(2, 95) 405 #define __restrict 406 #endif 407 408 /* 409 * GNU C version 2.96 adds explicit branch prediction so that 410 * the CPU back-end can hint the processor and also so that 411 * code blocks can be reordered such that the predicted path 412 * sees a more linear flow, thus improving cache behavior, etc. 413 * 414 * The following two macros provide us with a way to utilize this 415 * compiler feature. Use __predict_true() if you expect the expression 416 * to evaluate to true, and __predict_false() if you expect the 417 * expression to evaluate to false. 418 * 419 * A few notes about usage: 420 * 421 * * Generally, __predict_false() error condition checks (unless 422 * you have some _strong_ reason to do otherwise, in which case 423 * document it), and/or __predict_true() `no-error' condition 424 * checks, assuming you want to optimize for the no-error case. 425 * 426 * * Other than that, if you don't know the likelihood of a test 427 * succeeding from empirical or other `hard' evidence, don't 428 * make predictions. 429 * 430 * * These are meant to be used in places that are run `a lot'. 431 * It is wasteful to make predictions in code that is run 432 * seldomly (e.g. at subsystem initialization time) as the 433 * basic block reordering that this affects can often generate 434 * larger code. 435 */ 436 #if __GNUC_PREREQ__(2, 96) 437 #define __predict_true(exp) __builtin_expect((exp), 1) 438 #define __predict_false(exp) __builtin_expect((exp), 0) 439 #else 440 #define __predict_true(exp) (exp) 441 #define __predict_false(exp) (exp) 442 #endif 443 444 #if __GNUC_PREREQ__(4, 0) 445 #define __null_sentinel __attribute__((__sentinel__)) 446 #define __exported __attribute__((__visibility__("default"))) 447 #define __hidden __attribute__((__visibility__("hidden"))) 448 #else 449 #define __null_sentinel 450 #define __exported 451 #define __hidden 452 #endif 453 454 /* 455 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h> 456 * require it. 457 */ 458 #if __GNUC_PREREQ__(4, 1) 459 #define __offsetof(type, field) __builtin_offsetof(type, field) 460 #else 461 #ifndef __cplusplus 462 #define __offsetof(type, field) \ 463 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field)) 464 #else 465 #define __offsetof(type, field) \ 466 (__offsetof__ (reinterpret_cast <__size_t> \ 467 (&reinterpret_cast <const volatile char &> \ 468 (static_cast<type *> (0)->field)))) 469 #endif 470 #endif 471 #define __rangeof(type, start, end) \ 472 (__offsetof(type, end) - __offsetof(type, start)) 473 474 /* 475 * Given the pointer x to the member m of the struct s, return 476 * a pointer to the containing structure. When using GCC, we first 477 * assign pointer x to a local variable, to check that its type is 478 * compatible with member m. 479 */ 480 #if __GNUC_PREREQ__(3, 1) 481 #define __containerof(x, s, m) ({ \ 482 const volatile __typeof(((s *)0)->m) *__x = (x); \ 483 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\ 484 }) 485 #else 486 #define __containerof(x, s, m) \ 487 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m)) 488 #endif 489 490 /* 491 * Compiler-dependent macros to declare that functions take printf-like 492 * or scanf-like arguments. They are null except for versions of gcc 493 * that are known to support the features properly (old versions of gcc-2 494 * didn't permit keeping the keywords out of the application namespace). 495 */ 496 #if !__GNUC_PREREQ__(2, 7) 497 #define __printflike(fmtarg, firstvararg) 498 #define __scanflike(fmtarg, firstvararg) 499 #define __format_arg(fmtarg) 500 #define __strfmonlike(fmtarg, firstvararg) 501 #define __strftimelike(fmtarg, firstvararg) 502 #else 503 #define __printflike(fmtarg, firstvararg) \ 504 __attribute__((__format__ (__printf__, fmtarg, firstvararg))) 505 #define __scanflike(fmtarg, firstvararg) \ 506 __attribute__((__format__ (__scanf__, fmtarg, firstvararg))) 507 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg))) 508 #define __strfmonlike(fmtarg, firstvararg) \ 509 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg))) 510 #define __strftimelike(fmtarg, firstvararg) \ 511 __attribute__((__format__ (__strftime__, fmtarg, firstvararg))) 512 #endif 513 514 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */ 515 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \ 516 defined(__GNUC__) 517 #define __printf0like(fmtarg, firstvararg) \ 518 __attribute__((__format__ (__printf0__, fmtarg, firstvararg))) 519 #else 520 #define __printf0like(fmtarg, firstvararg) 521 #endif 522 523 #if defined(__GNUC__) 524 #define __strong_reference(sym,aliassym) \ 525 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym))) 526 #ifdef __STDC__ 527 #define __weak_reference(sym,alias) \ 528 __asm__(".weak " #alias); \ 529 __asm__(".equ " #alias ", " #sym) 530 #define __warn_references(sym,msg) \ 531 __asm__(".section .gnu.warning." #sym); \ 532 __asm__(".asciz \"" msg "\""); \ 533 __asm__(".previous") 534 #define __sym_compat(sym,impl,verid) \ 535 __asm__(".symver " #impl ", " #sym "@" #verid) 536 #define __sym_default(sym,impl,verid) \ 537 __asm__(".symver " #impl ", " #sym "@@@" #verid) 538 #else 539 #define __weak_reference(sym,alias) \ 540 __asm__(".weak alias"); \ 541 __asm__(".equ alias, sym") 542 #define __warn_references(sym,msg) \ 543 __asm__(".section .gnu.warning.sym"); \ 544 __asm__(".asciz \"msg\""); \ 545 __asm__(".previous") 546 #define __sym_compat(sym,impl,verid) \ 547 __asm__(".symver impl, sym@verid") 548 #define __sym_default(impl,sym,verid) \ 549 __asm__(".symver impl, sym@@@verid") 550 #endif /* __STDC__ */ 551 #endif /* __GNUC__ */ 552 553 #define __GLOBL(sym) __asm__(".globl " __XSTRING(sym)) 554 #define __WEAK(sym) __asm__(".weak " __XSTRING(sym)) 555 556 #if defined(__GNUC__) 557 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"") 558 #else 559 /* 560 * The following definition might not work well if used in header files, 561 * but it should be better than nothing. If you want a "do nothing" 562 * version, then it should generate some harmless declaration, such as: 563 * #define __IDSTRING(name,string) struct __hack 564 */ 565 #define __IDSTRING(name,string) static const char name[] __unused = string 566 #endif 567 568 /* 569 * Embed the rcs id of a source file in the resulting library. Note that in 570 * more recent ELF binutils, we use .ident allowing the ID to be stripped. 571 * Usage: 572 */ 573 #ifndef __FBSDID 574 #if !defined(STRIP_FBSDID) 575 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s) 576 #else 577 #define __FBSDID(s) struct __hack 578 #endif 579 #endif 580 581 #ifndef __RCSID 582 #ifndef NO__RCSID 583 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s) 584 #else 585 #define __RCSID(s) struct __hack 586 #endif 587 #endif 588 589 #ifndef __RCSID_SOURCE 590 #ifndef NO__RCSID_SOURCE 591 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s) 592 #else 593 #define __RCSID_SOURCE(s) struct __hack 594 #endif 595 #endif 596 597 #ifndef __SCCSID 598 #ifndef NO__SCCSID 599 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s) 600 #else 601 #define __SCCSID(s) struct __hack 602 #endif 603 #endif 604 605 #ifndef __COPYRIGHT 606 #ifndef NO__COPYRIGHT 607 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s) 608 #else 609 #define __COPYRIGHT(s) struct __hack 610 #endif 611 #endif 612 613 #ifndef __DECONST 614 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var)) 615 #endif 616 617 #ifndef __DEVOLATILE 618 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var)) 619 #endif 620 621 #ifndef __DEQUALIFY 622 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var)) 623 #endif 624 625 /*- 626 * The following definitions are an extension of the behavior originally 627 * implemented in <sys/_posix.h>, but with a different level of granularity. 628 * POSIX.1 requires that the macros we test be defined before any standard 629 * header file is included. 630 * 631 * Here's a quick run-down of the versions (and some informal names) 632 * defined(_POSIX_SOURCE) 1003.1-1988 633 * encoded as 198808 below 634 * _POSIX_C_SOURCE == 1 1003.1-1990 635 * encoded as 199009 below 636 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option 637 * encoded as 199209 below 638 * _POSIX_C_SOURCE == 199309 1003.1b-1993 639 * (1003.1 Issue 4, Single Unix Spec v1, Unix 93) 640 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995, 641 * and the omnibus ISO/IEC 9945-1: 1996 642 * (1003.1 Issue 5, Single Unix Spec v2, Unix 95) 643 * _POSIX_C_SOURCE == 200112 1003.1-2001 (1003.1 Issue 6, Unix 03) 644 * _POSIX_C_SOURCE == 200809 1003.1-2008 (1003.1 Issue 7) 645 * IEEE Std 1003.1-2017 (Rev of 1003.1-2008) is 646 * 1003.1-2008 with two TCs applied with 647 * _POSIX_C_SOURCE=200809 and _XOPEN_SOURCE=700 648 * 649 * In addition, the X/Open Portability Guide, which is now the Single UNIX 650 * Specification, defines a feature-test macro which indicates the version of 651 * that specification, and which subsumes _POSIX_C_SOURCE. 652 * 653 * Our macros begin with two underscores to avoid namespace screwage. 654 */ 655 656 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */ 657 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1 658 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */ 659 #define _POSIX_C_SOURCE 199009 660 #endif 661 662 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */ 663 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2 664 #undef _POSIX_C_SOURCE 665 #define _POSIX_C_SOURCE 199209 666 #endif 667 668 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */ 669 #ifdef _XOPEN_SOURCE 670 #if _XOPEN_SOURCE - 0 >= 700 671 #define __XSI_VISIBLE 700 672 #undef _POSIX_C_SOURCE 673 #define _POSIX_C_SOURCE 200809 674 #elif _XOPEN_SOURCE - 0 >= 600 675 #define __XSI_VISIBLE 600 676 #undef _POSIX_C_SOURCE 677 #define _POSIX_C_SOURCE 200112 678 #elif _XOPEN_SOURCE - 0 >= 500 679 #define __XSI_VISIBLE 500 680 #undef _POSIX_C_SOURCE 681 #define _POSIX_C_SOURCE 199506 682 #endif 683 #endif 684 685 /* 686 * Deal with all versions of POSIX. The ordering relative to the tests above is 687 * important. 688 */ 689 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE) 690 #define _POSIX_C_SOURCE 198808 691 #endif 692 #ifdef _POSIX_C_SOURCE 693 #if _POSIX_C_SOURCE >= 200809 694 #define __POSIX_VISIBLE 200809 695 #define __ISO_C_VISIBLE 1999 696 #elif _POSIX_C_SOURCE >= 200112 697 #define __POSIX_VISIBLE 200112 698 #define __ISO_C_VISIBLE 1999 699 #elif _POSIX_C_SOURCE >= 199506 700 #define __POSIX_VISIBLE 199506 701 #define __ISO_C_VISIBLE 1990 702 #elif _POSIX_C_SOURCE >= 199309 703 #define __POSIX_VISIBLE 199309 704 #define __ISO_C_VISIBLE 1990 705 #elif _POSIX_C_SOURCE >= 199209 706 #define __POSIX_VISIBLE 199209 707 #define __ISO_C_VISIBLE 1990 708 #elif _POSIX_C_SOURCE >= 199009 709 #define __POSIX_VISIBLE 199009 710 #define __ISO_C_VISIBLE 1990 711 #else 712 #define __POSIX_VISIBLE 198808 713 #define __ISO_C_VISIBLE 0 714 #endif /* _POSIX_C_SOURCE */ 715 /* 716 * Both glibc and OpenBSD enable c11 features when _ISOC11_SOURCE is defined, or 717 * when compiling with -stdc=c11. A strict reading of the standard would suggest 718 * doing it only for the former. However, a strict reading also requires C99 719 * mode only, so building with C11 is already undefined. Follow glibc's and 720 * OpenBSD's lead for this non-standard configuration for maximum compatibility. 721 */ 722 #if _ISOC11_SOURCE || (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) 723 #undef __ISO_C_VISIBLE 724 #define __ISO_C_VISIBLE 2011 725 #endif 726 #else 727 /*- 728 * Deal with _ANSI_SOURCE: 729 * If it is defined, and no other compilation environment is explicitly 730 * requested, then define our internal feature-test macros to zero. This 731 * makes no difference to the preprocessor (undefined symbols in preprocessing 732 * expressions are defined to have value zero), but makes it more convenient for 733 * a test program to print out the values. 734 * 735 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as 736 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation 737 * environment (and in fact we will never get here). 738 */ 739 #if defined(_ANSI_SOURCE) /* Hide almost everything. */ 740 #define __POSIX_VISIBLE 0 741 #define __XSI_VISIBLE 0 742 #define __BSD_VISIBLE 0 743 #define __ISO_C_VISIBLE 1990 744 #define __EXT1_VISIBLE 0 745 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */ 746 #define __POSIX_VISIBLE 0 747 #define __XSI_VISIBLE 0 748 #define __BSD_VISIBLE 0 749 #define __ISO_C_VISIBLE 1999 750 #define __EXT1_VISIBLE 0 751 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */ 752 #define __POSIX_VISIBLE 0 753 #define __XSI_VISIBLE 0 754 #define __BSD_VISIBLE 0 755 #define __ISO_C_VISIBLE 2011 756 #define __EXT1_VISIBLE 0 757 #else /* Default environment: show everything. */ 758 #define __POSIX_VISIBLE 200809 759 #define __XSI_VISIBLE 700 760 #define __BSD_VISIBLE 1 761 #define __ISO_C_VISIBLE 2011 762 #define __EXT1_VISIBLE 1 763 #endif 764 #endif 765 766 /* User override __EXT1_VISIBLE */ 767 #if defined(__STDC_WANT_LIB_EXT1__) 768 #undef __EXT1_VISIBLE 769 #if __STDC_WANT_LIB_EXT1__ 770 #define __EXT1_VISIBLE 1 771 #else 772 #define __EXT1_VISIBLE 0 773 #endif 774 #endif /* __STDC_WANT_LIB_EXT1__ */ 775 776 /* 777 * Old versions of GCC use non-standard ARM arch symbols; acle-compat.h 778 * translates them to __ARM_ARCH and the modern feature symbols defined by ARM. 779 */ 780 #if defined(__arm__) && !defined(__ARM_ARCH) 781 #include <machine/acle-compat.h> 782 #endif 783 784 /* 785 * Nullability qualifiers: currently only supported by Clang. 786 */ 787 #if !(defined(__clang__) && __has_feature(nullability)) 788 #define _Nonnull 789 #define _Nullable 790 #define _Null_unspecified 791 #define __NULLABILITY_PRAGMA_PUSH 792 #define __NULLABILITY_PRAGMA_POP 793 #else 794 #define __NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push") \ 795 _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"") 796 #define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop") 797 #endif 798 799 /* 800 * Type Safety Checking 801 * 802 * Clang provides additional attributes to enable checking type safety 803 * properties that cannot be enforced by the C type system. 804 */ 805 806 #if __has_attribute(__argument_with_type_tag__) && \ 807 __has_attribute(__type_tag_for_datatype__) 808 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \ 809 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx))) 810 #define __datatype_type_tag(kind, type) \ 811 __attribute__((__type_tag_for_datatype__(kind, type))) 812 #else 813 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) 814 #define __datatype_type_tag(kind, type) 815 #endif 816 817 /* 818 * Lock annotations. 819 * 820 * Clang provides support for doing basic thread-safety tests at 821 * compile-time, by marking which locks will/should be held when 822 * entering/leaving a functions. 823 * 824 * Furthermore, it is also possible to annotate variables and structure 825 * members to enforce that they are only accessed when certain locks are 826 * held. 827 */ 828 829 #if __has_extension(c_thread_safety_attributes) 830 #define __lock_annotate(x) __attribute__((x)) 831 #else 832 #define __lock_annotate(x) 833 #endif 834 835 /* Structure implements a lock. */ 836 #define __lockable __lock_annotate(lockable) 837 838 /* Function acquires an exclusive or shared lock. */ 839 #define __locks_exclusive(...) \ 840 __lock_annotate(exclusive_lock_function(__VA_ARGS__)) 841 #define __locks_shared(...) \ 842 __lock_annotate(shared_lock_function(__VA_ARGS__)) 843 844 /* Function attempts to acquire an exclusive or shared lock. */ 845 #define __trylocks_exclusive(...) \ 846 __lock_annotate(exclusive_trylock_function(__VA_ARGS__)) 847 #define __trylocks_shared(...) \ 848 __lock_annotate(shared_trylock_function(__VA_ARGS__)) 849 850 /* Function releases a lock. */ 851 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__)) 852 853 /* Function asserts that an exclusive or shared lock is held. */ 854 #define __asserts_exclusive(...) \ 855 __lock_annotate(assert_exclusive_lock(__VA_ARGS__)) 856 #define __asserts_shared(...) \ 857 __lock_annotate(assert_shared_lock(__VA_ARGS__)) 858 859 /* Function requires that an exclusive or shared lock is or is not held. */ 860 #define __requires_exclusive(...) \ 861 __lock_annotate(exclusive_locks_required(__VA_ARGS__)) 862 #define __requires_shared(...) \ 863 __lock_annotate(shared_locks_required(__VA_ARGS__)) 864 #define __requires_unlocked(...) \ 865 __lock_annotate(locks_excluded(__VA_ARGS__)) 866 867 /* Function should not be analyzed. */ 868 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis) 869 870 /* 871 * Function or variable should not be sanitized, e.g., by AddressSanitizer. 872 * GCC has the nosanitize attribute, but as a function attribute only, and 873 * warns on use as a variable attribute. 874 */ 875 #if __has_feature(address_sanitizer) && defined(__clang__) 876 #ifdef _KERNEL 877 #define __nosanitizeaddress __attribute__((no_sanitize("kernel-address"))) 878 #else 879 #define __nosanitizeaddress __attribute__((no_sanitize("address"))) 880 #endif 881 #else 882 #define __nosanitizeaddress 883 #endif 884 #if __has_feature(coverage_sanitizer) && defined(__clang__) 885 #define __nosanitizecoverage __attribute__((no_sanitize("coverage"))) 886 #else 887 #define __nosanitizecoverage 888 #endif 889 #if __has_feature(memory_sanitizer) && defined(__clang__) 890 #ifdef _KERNEL 891 #define __nosanitizememory __attribute__((no_sanitize("kernel-memory"))) 892 #else 893 #define __nosanitizememory __attribute__((no_sanitize("memory"))) 894 #endif 895 #else 896 #define __nosanitizememory 897 #endif 898 #if __has_feature(thread_sanitizer) && defined(__clang__) 899 #define __nosanitizethread __attribute__((no_sanitize("thread"))) 900 #else 901 #define __nosanitizethread 902 #endif 903 904 /* 905 * Make it possible to opt out of stack smashing protection. 906 */ 907 #if __has_attribute(no_stack_protector) 908 #define __nostackprotector __attribute__((no_stack_protector)) 909 #else 910 #define __nostackprotector \ 911 __attribute__((__optimize__("-fno-stack-protector"))) 912 #endif 913 914 /* Guard variables and structure members by lock. */ 915 #define __guarded_by(x) __lock_annotate(guarded_by(x)) 916 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x)) 917 918 /* Alignment builtins for better type checking and improved code generation. */ 919 /* Provide fallback versions for other compilers (GCC/Clang < 10): */ 920 #if !__has_builtin(__builtin_is_aligned) 921 #define __builtin_is_aligned(x, align) \ 922 (((__uintptr_t)(x) & ((align) - 1)) == 0) 923 #endif 924 #if !__has_builtin(__builtin_align_up) 925 #define __builtin_align_up(x, align) \ 926 ((__typeof__(x))(((__uintptr_t)(x)+((align)-1))&(~((align)-1)))) 927 #endif 928 #if !__has_builtin(__builtin_align_down) 929 #define __builtin_align_down(x, align) \ 930 ((__typeof__(x))((x)&(~((align)-1)))) 931 #endif 932 933 #define __align_up(x, y) __builtin_align_up(x, y) 934 #define __align_down(x, y) __builtin_align_down(x, y) 935 #define __is_aligned(x, y) __builtin_is_aligned(x, y) 936 937 #endif /* !_SYS_CDEFS_H_ */ 938