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[unleashed.git] / usr / src / boot / sys / sys / cdefs.h
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1 /*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Berkeley Software Design, Inc.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
32 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
33 * $FreeBSD$
36 #ifndef _SYS_CDEFS_H_
37 #define _SYS_CDEFS_H_
40 * Testing against Clang-specific extensions.
42 #ifndef __has_attribute
43 #define __has_attribute(x) 0
44 #endif
45 #ifndef __has_extension
46 #define __has_extension __has_feature
47 #endif
48 #ifndef __has_feature
49 #define __has_feature(x) 0
50 #endif
51 #ifndef __has_include
52 #define __has_include(x) 0
53 #endif
54 #ifndef __has_builtin
55 #define __has_builtin(x) 0
56 #endif
58 #if defined(__cplusplus)
59 #define __BEGIN_DECLS extern "C" {
60 #define __END_DECLS }
61 #else
62 #define __BEGIN_DECLS
63 #define __END_DECLS
64 #endif
67 * This code has been put in place to help reduce the addition of
68 * compiler specific defines in FreeBSD code. It helps to aid in
69 * having a compiler-agnostic source tree.
72 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
74 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
75 #define __GNUCLIKE_ASM 3
76 #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS
77 #else
78 #define __GNUCLIKE_ASM 2
79 #endif
80 #define __GNUCLIKE___TYPEOF 1
81 #define __GNUCLIKE___OFFSETOF 1
82 #define __GNUCLIKE___SECTION 1
84 #ifndef __INTEL_COMPILER
85 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1
86 #endif
88 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1
89 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
90 __INTEL_COMPILER < 800
91 #undef __GNUCLIKE_BUILTIN_CONSTANT_P
92 #endif
94 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3)
95 #define __GNUCLIKE_BUILTIN_VARARGS 1
96 #define __GNUCLIKE_BUILTIN_STDARG 1
97 #define __GNUCLIKE_BUILTIN_VAALIST 1
98 #endif
100 #if defined(__GNUC__)
101 #define __GNUC_VA_LIST_COMPATIBILITY 1
102 #endif
105 * Compiler memory barriers, specific to gcc and clang.
107 #if defined(__GNUC__)
108 #define __compiler_membar() __asm __volatile(" " : : : "memory")
109 #endif
111 #ifndef __INTEL_COMPILER
112 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1
113 #define __GNUCLIKE_MATH_BUILTIN_RELOPS
114 #endif
116 #define __GNUCLIKE_BUILTIN_MEMCPY 1
118 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
119 #define __CC_SUPPORTS_INLINE 1
120 #define __CC_SUPPORTS___INLINE 1
121 #define __CC_SUPPORTS___INLINE__ 1
123 #define __CC_SUPPORTS___FUNC__ 1
124 #define __CC_SUPPORTS_WARNING 1
126 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
128 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
130 #endif /* __GNUC__ || __INTEL_COMPILER */
133 * Macro to test if we're using a specific version of gcc or later.
135 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
136 #define __GNUC_PREREQ__(ma, mi) \
137 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
138 #else
139 #define __GNUC_PREREQ__(ma, mi) 0
140 #endif
143 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
144 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
145 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
146 * mode -- there must be no spaces between its arguments, and for nested
147 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
148 * concatenate double-quoted strings produced by the __STRING macro, but
149 * this only works with ANSI C.
151 * __XSTRING is like __STRING, but it expands any macros in its argument
152 * first. It is only available with ANSI C.
154 #if defined(__STDC__) || defined(__cplusplus)
155 #define __P(protos) protos /* full-blown ANSI C */
156 #define __CONCAT1(x,y) x ## y
157 #define __CONCAT(x,y) __CONCAT1(x,y)
158 #define __STRING(x) #x /* stringify without expanding x */
159 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
161 #define __const const /* define reserved names to standard */
162 #define __signed signed
163 #define __volatile volatile
164 #if defined(__cplusplus)
165 #define __inline inline /* convert to C++ keyword */
166 #else
167 #if !(defined(__CC_SUPPORTS___INLINE))
168 #define __inline /* delete GCC keyword */
169 #endif /* ! __CC_SUPPORTS___INLINE */
170 #endif /* !__cplusplus */
172 #else /* !(__STDC__ || __cplusplus) */
173 #define __P(protos) () /* traditional C preprocessor */
174 #define __CONCAT(x,y) x/**/y
175 #define __STRING(x) "x"
177 #if !defined(__CC_SUPPORTS___INLINE)
178 #define __const /* delete pseudo-ANSI C keywords */
179 #define __inline
180 #define __signed
181 #define __volatile
183 * In non-ANSI C environments, new programs will want ANSI-only C keywords
184 * deleted from the program and old programs will want them left alone.
185 * When using a compiler other than gcc, programs using the ANSI C keywords
186 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
187 * When using "gcc -traditional", we assume that this is the intent; if
188 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
190 #ifndef NO_ANSI_KEYWORDS
191 #define const /* delete ANSI C keywords */
192 #define inline
193 #define signed
194 #define volatile
195 #endif /* !NO_ANSI_KEYWORDS */
196 #endif /* !__CC_SUPPORTS___INLINE */
197 #endif /* !(__STDC__ || __cplusplus) */
200 * Compiler-dependent macros to help declare dead (non-returning) and
201 * pure (no side effects) functions, and unused variables. They are
202 * null except for versions of gcc that are known to support the features
203 * properly (old versions of gcc-2 supported the dead and pure features
204 * in a different (wrong) way). If we do not provide an implementation
205 * for a given compiler, let the compile fail if it is told to use
206 * a feature that we cannot live without.
208 #ifdef lint
209 #define __dead2
210 #define __pure2
211 #define __unused
212 #define __packed
213 #define __aligned(x)
214 #define __alloc_align(x)
215 #define __alloc_size(x)
216 #define __section(x)
217 #define __weak_symbol
218 #else
219 #define __weak_symbol __attribute__((__weak__))
220 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
221 #define __dead2
222 #define __pure2
223 #define __unused
224 #endif
225 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
226 #define __dead2 __attribute__((__noreturn__))
227 #define __pure2 __attribute__((__const__))
228 #define __unused
229 /* XXX Find out what to do for __packed, __aligned and __section */
230 #endif
231 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
232 #define __dead2 __attribute__((__noreturn__))
233 #define __pure2 __attribute__((__const__))
234 #define __unused __attribute__((__unused__))
235 #define __used __attribute__((__used__))
236 #define __packed __attribute__((__packed__))
237 #define __aligned(x) __attribute__((__aligned__(x)))
238 #define __section(x) __attribute__((__section__(x)))
239 #endif
240 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
241 #define __alloc_size(x) __attribute__((__alloc_size__(x)))
242 #else
243 #define __alloc_size(x)
244 #endif
245 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
246 #define __alloc_align(x) __attribute__((__alloc_align__(x)))
247 #else
248 #define __alloc_align(x)
249 #endif
250 #endif /* lint */
252 #if !__GNUC_PREREQ__(2, 95)
253 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
254 #endif
257 * Keywords added in C11.
260 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint)
262 #if !__has_extension(c_alignas)
263 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
264 __has_extension(cxx_alignas)
265 #define _Alignas(x) alignas(x)
266 #else
267 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
268 #define _Alignas(x) __aligned(x)
269 #endif
270 #endif
272 #if defined(__cplusplus) && __cplusplus >= 201103L
273 #define _Alignof(x) alignof(x)
274 #else
275 #define _Alignof(x) __alignof(x)
276 #endif
278 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic)
280 * No native support for _Atomic(). Place object in structure to prevent
281 * most forms of direct non-atomic access.
283 #define _Atomic(T) struct { T volatile __val; }
284 #endif
286 #if defined(__cplusplus) && __cplusplus >= 201103L
287 #define _Noreturn [[noreturn]]
288 #else
289 #define _Noreturn __dead2
290 #endif
292 #if !__has_extension(c_static_assert)
293 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
294 __has_extension(cxx_static_assert)
295 #define _Static_assert(x, y) static_assert(x, y)
296 #elif __GNUC_PREREQ__(4,6)
297 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
298 #elif defined(__COUNTER__)
299 #define _Static_assert(x, y) __Static_assert(x, __COUNTER__)
300 #define __Static_assert(x, y) ___Static_assert(x, y)
301 #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \
302 __unused
303 #else
304 #define _Static_assert(x, y) struct __hack
305 #endif
306 #endif
308 #if !__has_extension(c_thread_local)
310 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
311 * without actually supporting the thread_local keyword. Don't check for
312 * the presence of C++11 when defining _Thread_local.
314 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
315 __has_extension(cxx_thread_local)
316 #define _Thread_local thread_local
317 #else
318 #define _Thread_local __thread
319 #endif
320 #endif
322 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
325 * Emulation of C11 _Generic(). Unlike the previously defined C11
326 * keywords, it is not possible to implement this using exactly the same
327 * syntax. Therefore implement something similar under the name
328 * __generic(). Unlike _Generic(), this macro can only distinguish
329 * between a single type, so it requires nested invocations to
330 * distinguish multiple cases.
333 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
334 __has_extension(c_generic_selections)
335 #define __generic(expr, t, yes, no) \
336 _Generic(expr, t: yes, default: no)
337 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
338 #define __generic(expr, t, yes, no) \
339 __builtin_choose_expr( \
340 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
341 #endif
343 #if __GNUC_PREREQ__(2, 96)
344 #define __malloc_like __attribute__((__malloc__))
345 #define __pure __attribute__((__pure__))
346 #else
347 #define __malloc_like
348 #define __pure
349 #endif
351 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
352 #define __always_inline __attribute__((__always_inline__))
353 #else
354 #define __always_inline
355 #endif
357 #if __GNUC_PREREQ__(3, 1)
358 #define __noinline __attribute__ ((__noinline__))
359 #else
360 #define __noinline
361 #endif
363 #if __GNUC_PREREQ__(3, 3)
364 #define __nonnull(x) __attribute__((__nonnull__(x)))
365 #define __nonnull_all __attribute__((__nonnull__))
366 #else
367 #define __nonnull(x)
368 #define __nonnull_all
369 #endif
371 #if __GNUC_PREREQ__(3, 4)
372 #define __fastcall __attribute__((__fastcall__))
373 #define __result_use_check __attribute__((__warn_unused_result__))
374 #else
375 #define __fastcall
376 #define __result_use_check
377 #endif
379 #if __GNUC_PREREQ__(4, 1)
380 #define __returns_twice __attribute__((__returns_twice__))
381 #else
382 #define __returns_twice
383 #endif
385 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
386 #define __unreachable() __builtin_unreachable()
387 #else
388 #define __unreachable() ((void)0)
389 #endif
391 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
392 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
393 #define __func__ NULL
394 #endif
396 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
397 #define __LONG_LONG_SUPPORTED
398 #endif
400 /* C++11 exposes a load of C99 stuff */
401 #if defined(__cplusplus) && __cplusplus >= 201103L
402 #define __LONG_LONG_SUPPORTED
403 #ifndef __STDC_LIMIT_MACROS
404 #define __STDC_LIMIT_MACROS
405 #endif
406 #ifndef __STDC_CONSTANT_MACROS
407 #define __STDC_CONSTANT_MACROS
408 #endif
409 #endif
412 * GCC 2.95 provides `__restrict' as an extension to C90 to support the
413 * C99-specific `restrict' type qualifier. We happen to use `__restrict' as
414 * a way to define the `restrict' type qualifier without disturbing older
415 * software that is unaware of C99 keywords.
417 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
418 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
419 #define __restrict
420 #else
421 #define __restrict restrict
422 #endif
423 #endif
426 * GNU C version 2.96 adds explicit branch prediction so that
427 * the CPU back-end can hint the processor and also so that
428 * code blocks can be reordered such that the predicted path
429 * sees a more linear flow, thus improving cache behavior, etc.
431 * The following two macros provide us with a way to utilize this
432 * compiler feature. Use __predict_true() if you expect the expression
433 * to evaluate to true, and __predict_false() if you expect the
434 * expression to evaluate to false.
436 * A few notes about usage:
438 * * Generally, __predict_false() error condition checks (unless
439 * you have some _strong_ reason to do otherwise, in which case
440 * document it), and/or __predict_true() `no-error' condition
441 * checks, assuming you want to optimize for the no-error case.
443 * * Other than that, if you don't know the likelihood of a test
444 * succeeding from empirical or other `hard' evidence, don't
445 * make predictions.
447 * * These are meant to be used in places that are run `a lot'.
448 * It is wasteful to make predictions in code that is run
449 * seldomly (e.g. at subsystem initialization time) as the
450 * basic block reordering that this affects can often generate
451 * larger code.
453 #if __GNUC_PREREQ__(2, 96)
454 #define __predict_true(exp) __builtin_expect((exp), 1)
455 #define __predict_false(exp) __builtin_expect((exp), 0)
456 #else
457 #define __predict_true(exp) (exp)
458 #define __predict_false(exp) (exp)
459 #endif
461 #if __GNUC_PREREQ__(4, 0)
462 #define __null_sentinel __attribute__((__sentinel__))
463 #define __exported __attribute__((__visibility__("default")))
464 #define __hidden __attribute__((__visibility__("hidden")))
465 #else
466 #define __null_sentinel
467 #define __exported
468 #define __hidden
469 #endif
472 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
473 * require it.
475 #if __GNUC_PREREQ__(4, 1)
476 #define __offsetof(type, field) __builtin_offsetof(type, field)
477 #else
478 #ifndef __cplusplus
479 #define __offsetof(type, field) \
480 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
481 #else
482 #define __offsetof(type, field) \
483 (__offsetof__ (reinterpret_cast <__size_t> \
484 (&reinterpret_cast <const volatile char &> \
485 (static_cast<type *> (0)->field))))
486 #endif
487 #endif
488 #define __rangeof(type, start, end) \
489 (__offsetof(type, end) - __offsetof(type, start))
492 * Given the pointer x to the member m of the struct s, return
493 * a pointer to the containing structure. When using GCC, we first
494 * assign pointer x to a local variable, to check that its type is
495 * compatible with member m.
497 #if __GNUC_PREREQ__(3, 1)
498 #define __containerof(x, s, m) ({ \
499 const volatile __typeof(((s *)0)->m) *__x = (x); \
500 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
502 #else
503 #define __containerof(x, s, m) \
504 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
505 #endif
508 * Compiler-dependent macros to declare that functions take printf-like
509 * or scanf-like arguments. They are null except for versions of gcc
510 * that are known to support the features properly (old versions of gcc-2
511 * didn't permit keeping the keywords out of the application namespace).
513 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
514 #define __printflike(fmtarg, firstvararg)
515 #define __scanflike(fmtarg, firstvararg)
516 #define __format_arg(fmtarg)
517 #define __strfmonlike(fmtarg, firstvararg)
518 #define __strftimelike(fmtarg, firstvararg)
519 #else
520 #define __printflike(fmtarg, firstvararg) \
521 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
522 #define __scanflike(fmtarg, firstvararg) \
523 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
524 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg)))
525 #define __strfmonlike(fmtarg, firstvararg) \
526 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
527 #define __strftimelike(fmtarg, firstvararg) \
528 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
529 #endif
532 * FORTIFY_SOURCE, and perhaps other compiler-specific features, require
533 * the use of non-standard inlining. In general we should try to avoid
534 * using these but GCC-compatible compilers tend to support the extensions
535 * well enough to use them in limited cases.
537 #if defined(__GNUC_GNU_INLINE__) || defined(__GNUC_STDC_INLINE__)
538 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__artificial__)
539 #define __gnu_inline __attribute__((__gnu_inline__, __artificial__))
540 #else
541 #define __gnu_inline __attribute__((__gnu_inline__))
542 #endif /* artificial */
543 #else
544 #define __gnu_inline
545 #endif
547 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
548 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
549 defined(__GNUC__) && !defined(__INTEL_COMPILER)
550 #define __printf0like(fmtarg, firstvararg) \
551 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
552 #else
553 #define __printf0like(fmtarg, firstvararg)
554 #endif
556 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
557 #ifndef __INTEL_COMPILER
558 #define __strong_reference(sym,aliassym) \
559 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
560 #endif
561 #ifdef __STDC__
562 #define __weak_reference(sym,alias) \
563 __asm__(".weak " #alias); \
564 __asm__(".equ " #alias ", " #sym)
565 #define __warn_references(sym,msg) \
566 __asm__(".section .gnu.warning." #sym); \
567 __asm__(".asciz \"" msg "\""); \
568 __asm__(".previous")
569 #define __sym_compat(sym,impl,verid) \
570 __asm__(".symver " #impl ", " #sym "@" #verid)
571 #define __sym_default(sym,impl,verid) \
572 __asm__(".symver " #impl ", " #sym "@@" #verid)
573 #else
574 #define __weak_reference(sym,alias) \
575 __asm__(".weak alias"); \
576 __asm__(".equ alias, sym")
577 #define __warn_references(sym,msg) \
578 __asm__(".section .gnu.warning.sym"); \
579 __asm__(".asciz \"msg\""); \
580 __asm__(".previous")
581 #define __sym_compat(sym,impl,verid) \
582 __asm__(".symver impl, sym@verid")
583 #define __sym_default(impl,sym,verid) \
584 __asm__(".symver impl, sym@@verid")
585 #endif /* __STDC__ */
586 #endif /* __GNUC__ || __INTEL_COMPILER */
588 #define __GLOBL1(sym) __asm__(".globl " #sym)
589 #define __GLOBL(sym) __GLOBL1(sym)
591 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
592 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
593 #else
595 * The following definition might not work well if used in header files,
596 * but it should be better than nothing. If you want a "do nothing"
597 * version, then it should generate some harmless declaration, such as:
598 * #define __IDSTRING(name,string) struct __hack
600 #define __IDSTRING(name,string) static const char name[] __unused = string
601 #endif
604 * Embed the rcs id of a source file in the resulting library. Note that in
605 * more recent ELF binutils, we use .ident allowing the ID to be stripped.
606 * Usage:
607 * __FBSDID("$FreeBSD$");
609 #ifndef __FBSDID
610 #if !defined(lint) && !defined(STRIP_FBSDID)
611 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
612 #else
613 #define __FBSDID(s) struct __hack
614 #endif
615 #endif
617 #ifndef __RCSID
618 #ifndef NO__RCSID
619 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
620 #else
621 #define __RCSID(s) struct __hack
622 #endif
623 #endif
625 #ifndef __RCSID_SOURCE
626 #ifndef NO__RCSID_SOURCE
627 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
628 #else
629 #define __RCSID_SOURCE(s) struct __hack
630 #endif
631 #endif
633 #ifndef __SCCSID
634 #ifndef NO__SCCSID
635 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
636 #else
637 #define __SCCSID(s) struct __hack
638 #endif
639 #endif
641 #ifndef __COPYRIGHT
642 #ifndef NO__COPYRIGHT
643 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s)
644 #else
645 #define __COPYRIGHT(s) struct __hack
646 #endif
647 #endif
649 #ifndef __DECONST
650 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
651 #endif
653 #ifndef __DEVOLATILE
654 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
655 #endif
657 #ifndef __DEQUALIFY
658 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
659 #endif
662 * The following definitions are an extension of the behavior originally
663 * implemented in <sys/_posix.h>, but with a different level of granularity.
664 * POSIX.1 requires that the macros we test be defined before any standard
665 * header file is included.
667 * Here's a quick run-down of the versions:
668 * defined(_POSIX_SOURCE) 1003.1-1988
669 * _POSIX_C_SOURCE == 1 1003.1-1990
670 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
671 * _POSIX_C_SOURCE == 199309 1003.1b-1993
672 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
673 * and the omnibus ISO/IEC 9945-1: 1996
674 * _POSIX_C_SOURCE == 200112 1003.1-2001
675 * _POSIX_C_SOURCE == 200809 1003.1-2008
677 * In addition, the X/Open Portability Guide, which is now the Single UNIX
678 * Specification, defines a feature-test macro which indicates the version of
679 * that specification, and which subsumes _POSIX_C_SOURCE.
681 * Our macros begin with two underscores to avoid namespace screwage.
684 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
685 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
686 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
687 #define _POSIX_C_SOURCE 199009
688 #endif
690 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
691 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
692 #undef _POSIX_C_SOURCE
693 #define _POSIX_C_SOURCE 199209
694 #endif
696 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
697 #ifdef _XOPEN_SOURCE
698 #if _XOPEN_SOURCE - 0 >= 700
699 #define __XSI_VISIBLE 700
700 #undef _POSIX_C_SOURCE
701 #define _POSIX_C_SOURCE 200809
702 #elif _XOPEN_SOURCE - 0 >= 600
703 #define __XSI_VISIBLE 600
704 #undef _POSIX_C_SOURCE
705 #define _POSIX_C_SOURCE 200112
706 #elif _XOPEN_SOURCE - 0 >= 500
707 #define __XSI_VISIBLE 500
708 #undef _POSIX_C_SOURCE
709 #define _POSIX_C_SOURCE 199506
710 #endif
711 #endif
714 * Deal with all versions of POSIX. The ordering relative to the tests above is
715 * important.
717 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
718 #define _POSIX_C_SOURCE 198808
719 #endif
720 #ifdef _POSIX_C_SOURCE
721 #if _POSIX_C_SOURCE >= 200809
722 #define __POSIX_VISIBLE 200809
723 #define __ISO_C_VISIBLE 1999
724 #elif _POSIX_C_SOURCE >= 200112
725 #define __POSIX_VISIBLE 200112
726 #define __ISO_C_VISIBLE 1999
727 #elif _POSIX_C_SOURCE >= 199506
728 #define __POSIX_VISIBLE 199506
729 #define __ISO_C_VISIBLE 1990
730 #elif _POSIX_C_SOURCE >= 199309
731 #define __POSIX_VISIBLE 199309
732 #define __ISO_C_VISIBLE 1990
733 #elif _POSIX_C_SOURCE >= 199209
734 #define __POSIX_VISIBLE 199209
735 #define __ISO_C_VISIBLE 1990
736 #elif _POSIX_C_SOURCE >= 199009
737 #define __POSIX_VISIBLE 199009
738 #define __ISO_C_VISIBLE 1990
739 #else
740 #define __POSIX_VISIBLE 198808
741 #define __ISO_C_VISIBLE 0
742 #endif /* _POSIX_C_SOURCE */
743 #else
745 * Deal with _ANSI_SOURCE:
746 * If it is defined, and no other compilation environment is explicitly
747 * requested, then define our internal feature-test macros to zero. This
748 * makes no difference to the preprocessor (undefined symbols in preprocessing
749 * expressions are defined to have value zero), but makes it more convenient for
750 * a test program to print out the values.
752 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
753 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
754 * environment (and in fact we will never get here).
756 #if defined(_ANSI_SOURCE) /* Hide almost everything. */
757 #define __POSIX_VISIBLE 0
758 #define __XSI_VISIBLE 0
759 #define __BSD_VISIBLE 0
760 #define __ISO_C_VISIBLE 1990
761 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
762 #define __POSIX_VISIBLE 0
763 #define __XSI_VISIBLE 0
764 #define __BSD_VISIBLE 0
765 #define __ISO_C_VISIBLE 1999
766 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
767 #define __POSIX_VISIBLE 0
768 #define __XSI_VISIBLE 0
769 #define __BSD_VISIBLE 0
770 #define __ISO_C_VISIBLE 2011
771 #else /* Default environment: show everything. */
772 #define __POSIX_VISIBLE 200809
773 #define __XSI_VISIBLE 700
774 #define __BSD_VISIBLE 1
775 #define __ISO_C_VISIBLE 2011
776 #endif
777 #endif
779 #if defined(__mips) || defined(__powerpc64__) || defined(__riscv__)
780 #define __NO_TLS 1
781 #endif
784 * Type Safety Checking
786 * Clang provides additional attributes to enable checking type safety
787 * properties that cannot be enforced by the C type system.
790 #if __has_attribute(__argument_with_type_tag__) && \
791 __has_attribute(__type_tag_for_datatype__) && !defined(lint)
792 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
793 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
794 #define __datatype_type_tag(kind, type) \
795 __attribute__((__type_tag_for_datatype__(kind, type)))
796 #else
797 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx)
798 #define __datatype_type_tag(kind, type)
799 #endif
802 * Lock annotations.
804 * Clang provides support for doing basic thread-safety tests at
805 * compile-time, by marking which locks will/should be held when
806 * entering/leaving a functions.
808 * Furthermore, it is also possible to annotate variables and structure
809 * members to enforce that they are only accessed when certain locks are
810 * held.
813 #if __has_extension(c_thread_safety_attributes)
814 #define __lock_annotate(x) __attribute__((x))
815 #else
816 #define __lock_annotate(x)
817 #endif
819 /* Structure implements a lock. */
820 #define __lockable __lock_annotate(lockable)
822 /* Function acquires an exclusive or shared lock. */
823 #define __locks_exclusive(...) \
824 __lock_annotate(exclusive_lock_function(__VA_ARGS__))
825 #define __locks_shared(...) \
826 __lock_annotate(shared_lock_function(__VA_ARGS__))
828 /* Function attempts to acquire an exclusive or shared lock. */
829 #define __trylocks_exclusive(...) \
830 __lock_annotate(exclusive_trylock_function(__VA_ARGS__))
831 #define __trylocks_shared(...) \
832 __lock_annotate(shared_trylock_function(__VA_ARGS__))
834 /* Function releases a lock. */
835 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__))
837 /* Function asserts that an exclusive or shared lock is held. */
838 #define __asserts_exclusive(...) \
839 __lock_annotate(assert_exclusive_lock(__VA_ARGS__))
840 #define __asserts_shared(...) \
841 __lock_annotate(assert_shared_lock(__VA_ARGS__))
843 /* Function requires that an exclusive or shared lock is or is not held. */
844 #define __requires_exclusive(...) \
845 __lock_annotate(exclusive_locks_required(__VA_ARGS__))
846 #define __requires_shared(...) \
847 __lock_annotate(shared_locks_required(__VA_ARGS__))
848 #define __requires_unlocked(...) \
849 __lock_annotate(locks_excluded(__VA_ARGS__))
851 /* Function should not be analyzed. */
852 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis)
854 /* Guard variables and structure members by lock. */
855 #define __guarded_by(x) __lock_annotate(guarded_by(x))
856 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x))
858 #endif /* !_SYS_CDEFS_H_ */