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 * $FreeBSD$
36 */
37
38#ifndef	_SYS_CDEFS_H_
39#define	_SYS_CDEFS_H_
40
41#if defined(_KERNEL) && defined(_STANDALONE)
42#error "_KERNEL and _STANDALONE are mutually exclusive"
43#endif
44
45/*
46 * Testing against Clang-specific extensions.
47 */
48#ifndef	__has_attribute
49#define	__has_attribute(x)	0
50#endif
51#ifndef	__has_extension
52#define	__has_extension		__has_feature
53#endif
54#ifndef	__has_feature
55#define	__has_feature(x)	0
56#endif
57#ifndef	__has_include
58#define	__has_include(x)	0
59#endif
60#ifndef	__has_builtin
61#define	__has_builtin(x)	0
62#endif
63
64#if defined(__cplusplus)
65#define	__BEGIN_DECLS	extern "C" {
66#define	__END_DECLS	}
67#else
68#define	__BEGIN_DECLS
69#define	__END_DECLS
70#endif
71
72/*
73 * This code has been put in place to help reduce the addition of
74 * compiler specific defines in FreeBSD code.  It helps to aid in
75 * having a compiler-agnostic source tree.
76 */
77
78#if defined(__GNUC__) || defined(__INTEL_COMPILER)
79
80#if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
81#define	__GNUCLIKE_ASM 3
82#define	__GNUCLIKE_MATH_BUILTIN_CONSTANTS
83#else
84#define	__GNUCLIKE_ASM 2
85#endif
86#define	__GNUCLIKE___TYPEOF 1
87#define	__GNUCLIKE___OFFSETOF 1
88#define	__GNUCLIKE___SECTION 1
89
90#ifndef __INTEL_COMPILER
91#define	__GNUCLIKE_CTOR_SECTION_HANDLING 1
92#endif
93
94#define	__GNUCLIKE_BUILTIN_CONSTANT_P 1
95#if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
96   __INTEL_COMPILER < 800
97#undef __GNUCLIKE_BUILTIN_CONSTANT_P
98#endif
99
100#if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3)
101#define	__GNUCLIKE_BUILTIN_VARARGS 1
102#define	__GNUCLIKE_BUILTIN_STDARG 1
103#define	__GNUCLIKE_BUILTIN_VAALIST 1
104#endif
105
106#if defined(__GNUC__)
107#define	__GNUC_VA_LIST_COMPATIBILITY 1
108#endif
109
110/*
111 * Compiler memory barriers, specific to gcc and clang.
112 */
113#if defined(__GNUC__)
114#define	__compiler_membar()	__asm __volatile(" " : : : "memory")
115#endif
116
117#ifndef __INTEL_COMPILER
118#define	__GNUCLIKE_BUILTIN_NEXT_ARG 1
119#define	__GNUCLIKE_MATH_BUILTIN_RELOPS
120#endif
121
122#define	__GNUCLIKE_BUILTIN_MEMCPY 1
123
124/* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
125#define	__CC_SUPPORTS_INLINE 1
126#define	__CC_SUPPORTS___INLINE 1
127#define	__CC_SUPPORTS___INLINE__ 1
128
129#define	__CC_SUPPORTS___FUNC__ 1
130#define	__CC_SUPPORTS_WARNING 1
131
132#define	__CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
133
134#define	__CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
135
136#endif /* __GNUC__ || __INTEL_COMPILER */
137
138/*
139 * Macro to test if we're using a specific version of gcc or later.
140 */
141#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
142#define	__GNUC_PREREQ__(ma, mi)	\
143	(__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
144#else
145#define	__GNUC_PREREQ__(ma, mi)	0
146#endif
147
148/*
149 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
150 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
151 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
152 * mode -- there must be no spaces between its arguments, and for nested
153 * __CONCAT's, all the __CONCAT's must be at the left.  __CONCAT can also
154 * concatenate double-quoted strings produced by the __STRING macro, but
155 * this only works with ANSI C.
156 *
157 * __XSTRING is like __STRING, but it expands any macros in its argument
158 * first.  It is only available with ANSI C.
159 */
160#if defined(__STDC__) || defined(__cplusplus)
161#define	__P(protos)	protos		/* full-blown ANSI C */
162#define	__CONCAT1(x,y)	x ## y
163#define	__CONCAT(x,y)	__CONCAT1(x,y)
164#define	__STRING(x)	#x		/* stringify without expanding x */
165#define	__XSTRING(x)	__STRING(x)	/* expand x, then stringify */
166
167#define	__const		const		/* define reserved names to standard */
168#define	__signed	signed
169#define	__volatile	volatile
170#if defined(__cplusplus)
171#define	__inline	inline		/* convert to C++ keyword */
172#else
173#if !(defined(__CC_SUPPORTS___INLINE))
174#define	__inline			/* delete GCC keyword */
175#endif /* ! __CC_SUPPORTS___INLINE */
176#endif /* !__cplusplus */
177
178#else	/* !(__STDC__ || __cplusplus) */
179#define	__P(protos)	()		/* traditional C preprocessor */
180#define	__CONCAT(x,y)	x/**/y
181#define	__STRING(x)	"x"
182
183#if !defined(__CC_SUPPORTS___INLINE)
184#define	__const				/* delete pseudo-ANSI C keywords */
185#define	__inline
186#define	__signed
187#define	__volatile
188/*
189 * In non-ANSI C environments, new programs will want ANSI-only C keywords
190 * deleted from the program and old programs will want them left alone.
191 * When using a compiler other than gcc, programs using the ANSI C keywords
192 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
193 * When using "gcc -traditional", we assume that this is the intent; if
194 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
195 */
196#ifndef	NO_ANSI_KEYWORDS
197#define	const				/* delete ANSI C keywords */
198#define	inline
199#define	signed
200#define	volatile
201#endif	/* !NO_ANSI_KEYWORDS */
202#endif	/* !__CC_SUPPORTS___INLINE */
203#endif	/* !(__STDC__ || __cplusplus) */
204
205/*
206 * Compiler-dependent macros to help declare dead (non-returning) and
207 * pure (no side effects) functions, and unused variables.  They are
208 * null except for versions of gcc that are known to support the features
209 * properly (old versions of gcc-2 supported the dead and pure features
210 * in a different (wrong) way).  If we do not provide an implementation
211 * for a given compiler, let the compile fail if it is told to use
212 * a feature that we cannot live without.
213 */
214#define	__weak_symbol	__attribute__((__weak__))
215#if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
216#define	__dead2
217#define	__pure2
218#define	__unused
219#endif
220#if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
221#define	__dead2		__attribute__((__noreturn__))
222#define	__pure2		__attribute__((__const__))
223#define	__unused
224/* XXX Find out what to do for __packed, __aligned and __section */
225#endif
226#if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
227#define	__dead2		__attribute__((__noreturn__))
228#define	__pure2		__attribute__((__const__))
229#define	__unused	__attribute__((__unused__))
230#define	__used		__attribute__((__used__))
231#define	__packed	__attribute__((__packed__))
232#define	__aligned(x)	__attribute__((__aligned__(x)))
233#define	__section(x)	__attribute__((__section__(x)))
234#endif
235#if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
236#define	__alloc_size(x)	__attribute__((__alloc_size__(x)))
237#define	__alloc_size2(n, x)	__attribute__((__alloc_size__(n, x)))
238#else
239#define	__alloc_size(x)
240#define	__alloc_size2(n, x)
241#endif
242#if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
243#define	__alloc_align(x)	__attribute__((__alloc_align__(x)))
244#else
245#define	__alloc_align(x)
246#endif
247
248#if !__GNUC_PREREQ__(2, 95)
249#define	__alignof(x)	__offsetof(struct { char __a; x __b; }, __b)
250#endif
251
252/*
253 * Keywords added in C11.
254 */
255
256#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
257
258#if !__has_extension(c_alignas)
259#if (defined(__cplusplus) && __cplusplus >= 201103L) || \
260    __has_extension(cxx_alignas)
261#define	_Alignas(x)		alignas(x)
262#else
263/* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
264#define	_Alignas(x)		__aligned(x)
265#endif
266#endif
267
268#if defined(__cplusplus) && __cplusplus >= 201103L
269#define	_Alignof(x)		alignof(x)
270#else
271#define	_Alignof(x)		__alignof(x)
272#endif
273
274#if !defined(__cplusplus) && !__has_extension(c_atomic) && \
275	!__has_extension(cxx_atomic) && !__GNUC_PREREQ__(4, 7)
276/*
277 * No native support for _Atomic(). Place object in structure to prevent
278 * most forms of direct non-atomic access.
279 */
280#define	_Atomic(T)		struct { T volatile __val; }
281#endif
282
283#if defined(__cplusplus) && __cplusplus >= 201103L
284#define	_Noreturn		[[noreturn]]
285#else
286#define	_Noreturn		__dead2
287#endif
288
289#if !__has_extension(c_static_assert)
290#if (defined(__cplusplus) && __cplusplus >= 201103L) || \
291    __has_extension(cxx_static_assert)
292#define	_Static_assert(x, y)	static_assert(x, y)
293#elif __GNUC_PREREQ__(4,6) && !defined(__cplusplus)
294/* Nothing, gcc 4.6 and higher has _Static_assert built-in */
295#elif defined(__COUNTER__)
296#define	_Static_assert(x, y)	__Static_assert(x, __COUNTER__)
297#define	__Static_assert(x, y)	___Static_assert(x, y)
298#define	___Static_assert(x, y)	typedef char __assert_ ## y[(x) ? 1 : -1] \
299				__unused
300#else
301#define	_Static_assert(x, y)	struct __hack
302#endif
303#endif
304
305#if !__has_extension(c_thread_local)
306/*
307 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
308 * without actually supporting the thread_local keyword. Don't check for
309 * the presence of C++11 when defining _Thread_local.
310 */
311#if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
312    __has_extension(cxx_thread_local)
313#define	_Thread_local		thread_local
314#else
315#define	_Thread_local		__thread
316#endif
317#endif
318
319#endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
320
321/*
322 * Emulation of C11 _Generic().  Unlike the previously defined C11
323 * keywords, it is not possible to implement this using exactly the same
324 * syntax.  Therefore implement something similar under the name
325 * __generic().  Unlike _Generic(), this macro can only distinguish
326 * between a single type, so it requires nested invocations to
327 * distinguish multiple cases.
328 */
329
330#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
331    __has_extension(c_generic_selections)
332#define	__generic(expr, t, yes, no)					\
333	_Generic(expr, t: yes, default: no)
334#elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
335#define	__generic(expr, t, yes, no)					\
336	__builtin_choose_expr(						\
337	    __builtin_types_compatible_p(__typeof(expr), t), yes, no)
338#endif
339
340/*
341 * C99 Static array indices in function parameter declarations.  Syntax such as:
342 * void bar(int myArray[static 10]);
343 * is allowed in C99 but not in C++.  Define __min_size appropriately so
344 * headers using it can be compiled in either language.  Use like this:
345 * void bar(int myArray[__min_size(10)]);
346 */
347#if !defined(__cplusplus) && \
348    (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \
349    (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901))
350#define __min_size(x)	static (x)
351#else
352#define __min_size(x)	(x)
353#endif
354
355#if __GNUC_PREREQ__(2, 96)
356#define	__malloc_like	__attribute__((__malloc__))
357#define	__pure		__attribute__((__pure__))
358#else
359#define	__malloc_like
360#define	__pure
361#endif
362
363#if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
364#define	__always_inline	__attribute__((__always_inline__))
365#else
366#define	__always_inline
367#endif
368
369#if __GNUC_PREREQ__(3, 1)
370#define	__noinline	__attribute__ ((__noinline__))
371#else
372#define	__noinline
373#endif
374
375#if __GNUC_PREREQ__(3, 4)
376#define	__fastcall	__attribute__((__fastcall__))
377#define	__result_use_check	__attribute__((__warn_unused_result__))
378#else
379#define	__fastcall
380#define	__result_use_check
381#endif
382
383#if __GNUC_PREREQ__(4, 1)
384#define	__returns_twice	__attribute__((__returns_twice__))
385#else
386#define	__returns_twice
387#endif
388
389#if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
390#define	__unreachable()	__builtin_unreachable()
391#else
392#define	__unreachable()	((void)0)
393#endif
394
395/* XXX: should use `#if __STDC_VERSION__ < 199901'. */
396#if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
397#define	__func__	NULL
398#endif
399
400#if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
401#define	__LONG_LONG_SUPPORTED
402#endif
403
404/* C++11 exposes a load of C99 stuff */
405#if defined(__cplusplus) && __cplusplus >= 201103L
406#define	__LONG_LONG_SUPPORTED
407#ifndef	__STDC_LIMIT_MACROS
408#define	__STDC_LIMIT_MACROS
409#endif
410#ifndef	__STDC_CONSTANT_MACROS
411#define	__STDC_CONSTANT_MACROS
412#endif
413#endif
414
415/*
416 * GCC 2.95 provides `__restrict' as an extension to C90 to support the
417 * C99-specific `restrict' type qualifier.  We happen to use `__restrict' as
418 * a way to define the `restrict' type qualifier without disturbing older
419 * software that is unaware of C99 keywords.
420 */
421#if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
422#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901
423#define	__restrict
424#else
425#define	__restrict	restrict
426#endif
427#endif
428
429/*
430 * GNU C version 2.96 adds explicit branch prediction so that
431 * the CPU back-end can hint the processor and also so that
432 * code blocks can be reordered such that the predicted path
433 * sees a more linear flow, thus improving cache behavior, etc.
434 *
435 * The following two macros provide us with a way to utilize this
436 * compiler feature.  Use __predict_true() if you expect the expression
437 * to evaluate to true, and __predict_false() if you expect the
438 * expression to evaluate to false.
439 *
440 * A few notes about usage:
441 *
442 *	* Generally, __predict_false() error condition checks (unless
443 *	  you have some _strong_ reason to do otherwise, in which case
444 *	  document it), and/or __predict_true() `no-error' condition
445 *	  checks, assuming you want to optimize for the no-error case.
446 *
447 *	* Other than that, if you don't know the likelihood of a test
448 *	  succeeding from empirical or other `hard' evidence, don't
449 *	  make predictions.
450 *
451 *	* These are meant to be used in places that are run `a lot'.
452 *	  It is wasteful to make predictions in code that is run
453 *	  seldomly (e.g. at subsystem initialization time) as the
454 *	  basic block reordering that this affects can often generate
455 *	  larger code.
456 */
457#if __GNUC_PREREQ__(2, 96)
458#define	__predict_true(exp)     __builtin_expect((exp), 1)
459#define	__predict_false(exp)    __builtin_expect((exp), 0)
460#else
461#define	__predict_true(exp)     (exp)
462#define	__predict_false(exp)    (exp)
463#endif
464
465#if __GNUC_PREREQ__(4, 0)
466#define	__null_sentinel	__attribute__((__sentinel__))
467#define	__exported	__attribute__((__visibility__("default")))
468#define	__hidden	__attribute__((__visibility__("hidden")))
469#else
470#define	__null_sentinel
471#define	__exported
472#define	__hidden
473#endif
474
475/*
476 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
477 * require it.
478 */
479#if __GNUC_PREREQ__(4, 1)
480#define	__offsetof(type, field)	 __builtin_offsetof(type, field)
481#else
482#ifndef __cplusplus
483#define	__offsetof(type, field) \
484	((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
485#else
486#define	__offsetof(type, field)					\
487  (__offsetof__ (reinterpret_cast <__size_t>			\
488                 (&reinterpret_cast <const volatile char &>	\
489                  (static_cast<type *> (0)->field))))
490#endif
491#endif
492#define	__rangeof(type, start, end) \
493	(__offsetof(type, end) - __offsetof(type, start))
494
495/*
496 * Given the pointer x to the member m of the struct s, return
497 * a pointer to the containing structure.  When using GCC, we first
498 * assign pointer x to a local variable, to check that its type is
499 * compatible with member m.
500 */
501#if __GNUC_PREREQ__(3, 1)
502#define	__containerof(x, s, m) ({					\
503	const volatile __typeof(((s *)0)->m) *__x = (x);		\
504	__DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
505})
506#else
507#define	__containerof(x, s, m)						\
508	__DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
509#endif
510
511/*
512 * Compiler-dependent macros to declare that functions take printf-like
513 * or scanf-like arguments.  They are null except for versions of gcc
514 * that are known to support the features properly (old versions of gcc-2
515 * didn't permit keeping the keywords out of the application namespace).
516 */
517#if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
518#define	__printflike(fmtarg, firstvararg)
519#define	__scanflike(fmtarg, firstvararg)
520#define	__format_arg(fmtarg)
521#define	__strfmonlike(fmtarg, firstvararg)
522#define	__strftimelike(fmtarg, firstvararg)
523#else
524#define	__printflike(fmtarg, firstvararg) \
525	    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
526#define	__scanflike(fmtarg, firstvararg) \
527	    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
528#define	__format_arg(fmtarg)	__attribute__((__format_arg__ (fmtarg)))
529#define	__strfmonlike(fmtarg, firstvararg) \
530	    __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
531#define	__strftimelike(fmtarg, firstvararg) \
532	    __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
533#endif
534
535/* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
536#if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
537    defined(__GNUC__) && !defined(__INTEL_COMPILER)
538#define	__printf0like(fmtarg, firstvararg) \
539	    __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
540#else
541#define	__printf0like(fmtarg, firstvararg)
542#endif
543
544#if defined(__GNUC__) || defined(__INTEL_COMPILER)
545#ifndef __INTEL_COMPILER
546#define	__strong_reference(sym,aliassym)	\
547	extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
548#endif
549#ifdef __STDC__
550#define	__weak_reference(sym,alias)	\
551	__asm__(".weak " #alias);	\
552	__asm__(".equ "  #alias ", " #sym)
553#define	__warn_references(sym,msg)	\
554	__asm__(".section .gnu.warning." #sym);	\
555	__asm__(".asciz \"" msg "\"");	\
556	__asm__(".previous")
557#define	__sym_compat(sym,impl,verid)	\
558	__asm__(".symver " #impl ", " #sym "@" #verid)
559#define	__sym_default(sym,impl,verid)	\
560	__asm__(".symver " #impl ", " #sym "@@@" #verid)
561#else
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(impl,sym,verid)	\
572	__asm__(".symver impl, sym@@@verid")
573#endif	/* __STDC__ */
574#endif	/* __GNUC__ || __INTEL_COMPILER */
575
576#define	__GLOBL1(sym)	__asm__(".globl " #sym)
577#define	__GLOBL(sym)	__GLOBL1(sym)
578
579#if defined(__GNUC__) || defined(__INTEL_COMPILER)
580#define	__IDSTRING(name,string)	__asm__(".ident\t\"" string "\"")
581#else
582/*
583 * The following definition might not work well if used in header files,
584 * but it should be better than nothing.  If you want a "do nothing"
585 * version, then it should generate some harmless declaration, such as:
586 *    #define	__IDSTRING(name,string)	struct __hack
587 */
588#define	__IDSTRING(name,string)	static const char name[] __unused = string
589#endif
590
591/*
592 * Embed the rcs id of a source file in the resulting library.  Note that in
593 * more recent ELF binutils, we use .ident allowing the ID to be stripped.
594 * Usage:
595 *	__FBSDID("$FreeBSD$");
596 */
597#ifndef	__FBSDID
598#if !defined(STRIP_FBSDID)
599#define	__FBSDID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
600#else
601#define	__FBSDID(s)	struct __hack
602#endif
603#endif
604
605#ifndef	__RCSID
606#ifndef	NO__RCSID
607#define	__RCSID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
608#else
609#define	__RCSID(s)	struct __hack
610#endif
611#endif
612
613#ifndef	__RCSID_SOURCE
614#ifndef	NO__RCSID_SOURCE
615#define	__RCSID_SOURCE(s)	__IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
616#else
617#define	__RCSID_SOURCE(s)	struct __hack
618#endif
619#endif
620
621#ifndef	__SCCSID
622#ifndef	NO__SCCSID
623#define	__SCCSID(s)	__IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
624#else
625#define	__SCCSID(s)	struct __hack
626#endif
627#endif
628
629#ifndef	__COPYRIGHT
630#ifndef	NO__COPYRIGHT
631#define	__COPYRIGHT(s)	__IDSTRING(__CONCAT(__copyright_,__LINE__),s)
632#else
633#define	__COPYRIGHT(s)	struct __hack
634#endif
635#endif
636
637#ifndef	__DECONST
638#define	__DECONST(type, var)	((type)(__uintptr_t)(const void *)(var))
639#endif
640
641#ifndef	__DEVOLATILE
642#define	__DEVOLATILE(type, var)	((type)(__uintptr_t)(volatile void *)(var))
643#endif
644
645#ifndef	__DEQUALIFY
646#define	__DEQUALIFY(type, var)	((type)(__uintptr_t)(const volatile void *)(var))
647#endif
648
649/*-
650 * The following definitions are an extension of the behavior originally
651 * implemented in <sys/_posix.h>, but with a different level of granularity.
652 * POSIX.1 requires that the macros we test be defined before any standard
653 * header file is included.
654 *
655 * Here's a quick run-down of the versions:
656 *  defined(_POSIX_SOURCE)		1003.1-1988
657 *  _POSIX_C_SOURCE == 1		1003.1-1990
658 *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
659 *  _POSIX_C_SOURCE == 199309		1003.1b-1993
660 *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
661 *					and the omnibus ISO/IEC 9945-1: 1996
662 *  _POSIX_C_SOURCE == 200112		1003.1-2001
663 *  _POSIX_C_SOURCE == 200809		1003.1-2008
664 *
665 * In addition, the X/Open Portability Guide, which is now the Single UNIX
666 * Specification, defines a feature-test macro which indicates the version of
667 * that specification, and which subsumes _POSIX_C_SOURCE.
668 *
669 * Our macros begin with two underscores to avoid namespace screwage.
670 */
671
672/* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
673#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
674#undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
675#define	_POSIX_C_SOURCE		199009
676#endif
677
678/* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
679#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
680#undef _POSIX_C_SOURCE
681#define	_POSIX_C_SOURCE		199209
682#endif
683
684/* Deal with various X/Open Portability Guides and Single UNIX Spec. */
685#ifdef _XOPEN_SOURCE
686#if _XOPEN_SOURCE - 0 >= 700
687#define	__XSI_VISIBLE		700
688#undef _POSIX_C_SOURCE
689#define	_POSIX_C_SOURCE		200809
690#elif _XOPEN_SOURCE - 0 >= 600
691#define	__XSI_VISIBLE		600
692#undef _POSIX_C_SOURCE
693#define	_POSIX_C_SOURCE		200112
694#elif _XOPEN_SOURCE - 0 >= 500
695#define	__XSI_VISIBLE		500
696#undef _POSIX_C_SOURCE
697#define	_POSIX_C_SOURCE		199506
698#endif
699#endif
700
701/*
702 * Deal with all versions of POSIX.  The ordering relative to the tests above is
703 * important.
704 */
705#if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
706#define	_POSIX_C_SOURCE		198808
707#endif
708#ifdef _POSIX_C_SOURCE
709#if _POSIX_C_SOURCE >= 200809
710#define	__POSIX_VISIBLE		200809
711#define	__ISO_C_VISIBLE		1999
712#elif _POSIX_C_SOURCE >= 200112
713#define	__POSIX_VISIBLE		200112
714#define	__ISO_C_VISIBLE		1999
715#elif _POSIX_C_SOURCE >= 199506
716#define	__POSIX_VISIBLE		199506
717#define	__ISO_C_VISIBLE		1990
718#elif _POSIX_C_SOURCE >= 199309
719#define	__POSIX_VISIBLE		199309
720#define	__ISO_C_VISIBLE		1990
721#elif _POSIX_C_SOURCE >= 199209
722#define	__POSIX_VISIBLE		199209
723#define	__ISO_C_VISIBLE		1990
724#elif _POSIX_C_SOURCE >= 199009
725#define	__POSIX_VISIBLE		199009
726#define	__ISO_C_VISIBLE		1990
727#else
728#define	__POSIX_VISIBLE		198808
729#define	__ISO_C_VISIBLE		0
730#endif /* _POSIX_C_SOURCE */
731#else
732/*-
733 * Deal with _ANSI_SOURCE:
734 * If it is defined, and no other compilation environment is explicitly
735 * requested, then define our internal feature-test macros to zero.  This
736 * makes no difference to the preprocessor (undefined symbols in preprocessing
737 * expressions are defined to have value zero), but makes it more convenient for
738 * a test program to print out the values.
739 *
740 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
741 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
742 * environment (and in fact we will never get here).
743 */
744#if defined(_ANSI_SOURCE)	/* Hide almost everything. */
745#define	__POSIX_VISIBLE		0
746#define	__XSI_VISIBLE		0
747#define	__BSD_VISIBLE		0
748#define	__ISO_C_VISIBLE		1990
749#define	__EXT1_VISIBLE		0
750#elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
751#define	__POSIX_VISIBLE		0
752#define	__XSI_VISIBLE		0
753#define	__BSD_VISIBLE		0
754#define	__ISO_C_VISIBLE		1999
755#define	__EXT1_VISIBLE		0
756#elif defined(_C11_SOURCE)	/* Localism to specify strict C11 env. */
757#define	__POSIX_VISIBLE		0
758#define	__XSI_VISIBLE		0
759#define	__BSD_VISIBLE		0
760#define	__ISO_C_VISIBLE		2011
761#define	__EXT1_VISIBLE		0
762#else				/* Default environment: show everything. */
763#define	__POSIX_VISIBLE		200809
764#define	__XSI_VISIBLE		700
765#define	__BSD_VISIBLE		1
766#define	__ISO_C_VISIBLE		2011
767#define	__EXT1_VISIBLE		1
768#endif
769#endif
770
771/* User override __EXT1_VISIBLE */
772#if defined(__STDC_WANT_LIB_EXT1__)
773#undef	__EXT1_VISIBLE
774#if __STDC_WANT_LIB_EXT1__
775#define	__EXT1_VISIBLE		1
776#else
777#define	__EXT1_VISIBLE		0
778#endif
779#endif /* __STDC_WANT_LIB_EXT1__ */
780
781#if defined(__mips) || defined(__riscv) || \
782    (defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1))
783#define	__NO_TLS 1
784#endif
785
786/*
787 * Old versions of GCC use non-standard ARM arch symbols; acle-compat.h
788 * translates them to __ARM_ARCH and the modern feature symbols defined by ARM.
789 */
790#if defined(__arm__) && !defined(__ARM_ARCH)
791#include <machine/acle-compat.h>
792#endif
793
794/*
795 * Nullability qualifiers: currently only supported by Clang.
796 */
797#if !(defined(__clang__) && __has_feature(nullability))
798#define	_Nonnull
799#define	_Nullable
800#define	_Null_unspecified
801#define	__NULLABILITY_PRAGMA_PUSH
802#define	__NULLABILITY_PRAGMA_POP
803#else
804#define	__NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push")	\
805	_Pragma("clang diagnostic ignored \"-Wnullability-completeness\"")
806#define	__NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop")
807#endif
808
809/*
810 * Type Safety Checking
811 *
812 * Clang provides additional attributes to enable checking type safety
813 * properties that cannot be enforced by the C type system.
814 */
815
816#if __has_attribute(__argument_with_type_tag__) && \
817    __has_attribute(__type_tag_for_datatype__)
818#define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
819	    __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
820#define	__datatype_type_tag(kind, type) \
821	    __attribute__((__type_tag_for_datatype__(kind, type)))
822#else
823#define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx)
824#define	__datatype_type_tag(kind, type)
825#endif
826
827/*
828 * Lock annotations.
829 *
830 * Clang provides support for doing basic thread-safety tests at
831 * compile-time, by marking which locks will/should be held when
832 * entering/leaving a functions.
833 *
834 * Furthermore, it is also possible to annotate variables and structure
835 * members to enforce that they are only accessed when certain locks are
836 * held.
837 */
838
839#if __has_extension(c_thread_safety_attributes)
840#define	__lock_annotate(x)	__attribute__((x))
841#else
842#define	__lock_annotate(x)
843#endif
844
845/* Structure implements a lock. */
846#define	__lockable		__lock_annotate(lockable)
847
848/* Function acquires an exclusive or shared lock. */
849#define	__locks_exclusive(...) \
850	__lock_annotate(exclusive_lock_function(__VA_ARGS__))
851#define	__locks_shared(...) \
852	__lock_annotate(shared_lock_function(__VA_ARGS__))
853
854/* Function attempts to acquire an exclusive or shared lock. */
855#define	__trylocks_exclusive(...) \
856	__lock_annotate(exclusive_trylock_function(__VA_ARGS__))
857#define	__trylocks_shared(...) \
858	__lock_annotate(shared_trylock_function(__VA_ARGS__))
859
860/* Function releases a lock. */
861#define	__unlocks(...)		__lock_annotate(unlock_function(__VA_ARGS__))
862
863/* Function asserts that an exclusive or shared lock is held. */
864#define	__asserts_exclusive(...) \
865	__lock_annotate(assert_exclusive_lock(__VA_ARGS__))
866#define	__asserts_shared(...) \
867	__lock_annotate(assert_shared_lock(__VA_ARGS__))
868
869/* Function requires that an exclusive or shared lock is or is not held. */
870#define	__requires_exclusive(...) \
871	__lock_annotate(exclusive_locks_required(__VA_ARGS__))
872#define	__requires_shared(...) \
873	__lock_annotate(shared_locks_required(__VA_ARGS__))
874#define	__requires_unlocked(...) \
875	__lock_annotate(locks_excluded(__VA_ARGS__))
876
877/* Function should not be analyzed. */
878#define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
879
880/*
881 * Function or variable should not be sanitized, i.e. by AddressSanitizer.
882 * GCC has the nosanitize attribute, but as a function attribute only, and
883 * warns on use as a variable attribute.
884 */
885#if __has_attribute(no_sanitize) && defined(__clang__)
886#define __nosanitizeaddress	__attribute__((no_sanitize("address")))
887#define __nosanitizethread	__attribute__((no_sanitize("thread")))
888#else
889#define __nosanitizeaddress
890#define __nosanitizethread
891#endif
892
893/* Guard variables and structure members by lock. */
894#define	__guarded_by(x)		__lock_annotate(guarded_by(x))
895#define	__pt_guarded_by(x)	__lock_annotate(pt_guarded_by(x))
896
897#endif /* !_SYS_CDEFS_H_ */
898