master
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_ */