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
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 * 3. 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
32 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
33 * $FreeBSD: src/sys/sys/cdefs.h,v 1.28.2.8 2002/09/18 04:05:13 mikeh Exp $
40 * Testing against Clang-specific extensions.
43 #ifndef __has_extension
44 #define __has_extension __has_feature
47 #define __has_feature(x) 0
50 #define __has_include(x) 0
53 #define __has_builtin(x) 0
57 * Macro to test if we are using a specific version of gcc or later.
59 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
60 #define __GNUC_PREREQ__(ma, mi) \
61 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
63 #define __GNUC_PREREQ__(ma, mi) 0
66 #if defined(__cplusplus)
67 #if __GNUC_PREREQ__(4, 0)
68 #define __BEGIN_DECLS _Pragma("GCC visibility push(default)") extern "C" {
69 #define __END_DECLS } _Pragma("GCC visibility pop")
71 #define __BEGIN_DECLS extern "C" {
80 * The __VM_CACHELINE_SIZE macro defines the common cache line alignment
81 * size that can be found across most recent and somewhat latest Intel
82 * hardware, i.e. L1 cache sizes etc.
84 * If needed, this value can be TUNED. Suitable values for this macro
85 * are 32, 64 and 128 bytes. The unit of measurement for this macro is
88 * XXX: This macro and related macros will eventually move to a MD
89 * header, but currently, we do need such a hierarchy.
91 #define __VM_CACHELINE_SIZE 64
92 #define __VM_CACHELINE_MASK (__VM_CACHELINE_SIZE - 1)
93 #define __VM_CACHELINE_ALIGN(n) \
94 (((n) + __VM_CACHELINE_MASK) & ~__VM_CACHELINE_MASK)
97 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
98 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
99 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
100 * mode -- there must be no spaces between its arguments, and for nested
101 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
102 * concatenate double-quoted strings produced by the __STRING macro, but
103 * this only works with ANSI C.
105 * __XSTRING is like __STRING, but it expands any macros in its argument
106 * first. It is only available with ANSI C.
108 #if defined(__STDC__) || defined(__cplusplus)
109 #define __P(protos) protos /* full-blown ANSI C */
110 #define __CONCAT1(x,y) x ## y
111 #define __CONCAT(x,y) __CONCAT1(x,y)
112 #define __STRING(x) #x /* stringify without expanding x */
113 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
115 #define __const const /* define reserved names to standard */
116 #define __signed signed
117 #define __volatile volatile
118 #if defined(__cplusplus)
119 #define __inline inline /* convert to C++ keyword */
122 #define __inline /* delete GCC keyword */
123 #endif /* !__GNUC__ */
124 #endif /* !__cplusplus */
126 #else /* !(__STDC__ || __cplusplus) */
127 #define __P(protos) () /* traditional C preprocessor */
128 #define __CONCAT(x,y) x/**/y
129 #define __STRING(x) "x"
132 #define __const /* delete pseudo-ANSI C keywords */
137 * In non-ANSI C environments, new programs will want ANSI-only C keywords
138 * deleted from the program and old programs will want them left alone.
139 * When using a compiler other than gcc, programs using the ANSI C keywords
140 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
141 * When using "gcc -traditional", we assume that this is the intent; if
142 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
144 #ifndef NO_ANSI_KEYWORDS
145 #define const /* delete ANSI C keywords */
149 #endif /* !NO_ANSI_KEYWORDS */
150 #endif /* !__GNUC__ */
151 #endif /* !(__STDC__ || __cplusplus) */
154 * Compiler-dependent macros to help declare dead (non-returning) and
155 * pure (no side effects) functions, and unused variables. They are
156 * null except for versions of gcc that are known to support the features
157 * properly (old versions of gcc-2 supported the dead and pure features
158 * in a different (wrong) way).
169 #define __always_inline
172 #define __returns_twice
176 #if __GNUC_PREREQ__(2, 7)
177 #define __dead2 __attribute__((__noreturn__))
178 #define __pure2 __attribute__((__const__))
179 #define __unused __attribute__((__unused__))
180 #define __packed __attribute__((__packed__))
181 #define __aligned(x) __attribute__((__aligned__(x)))
182 #define __section(x) __attribute__((__section__(x)))
189 #if __GNUC_PREREQ__(2, 96)
190 #define __pure __attribute__((__pure__))
192 #define __pure __pure2
195 #if __GNUC_PREREQ__(3, 1)
196 #define __always_inline __attribute__((__always_inline__))
197 #define __noinline __attribute__((__noinline__))
199 #define __always_inline
203 #if __GNUC_PREREQ__(3, 3)
204 #define __heedresult __attribute__((__warn_unused_result__))
205 #define __nonnull(x) __attribute__((__nonnull__(x)))
206 #define __used __attribute__((__used__))
210 #define __used __unused
213 #if __GNUC_PREREQ__(4, 1)
214 #define __returns_twice __attribute__((__returns_twice__))
216 #define __returns_twice
221 #if !__GNUC_PREREQ__(2, 7) && __STDC_VERSION < 199901
222 #define __func__ NULL
225 #if (__GNUC_PREREQ__(2, 0) && !defined(__STRICT_ANSI__)) || \
226 __STDC_VERSION__ >= 199901
227 #define __LONG_LONG_SUPPORTED
230 /* C++11 exposes a load of C99 stuff */
231 #if defined(__cplusplus) && __cplusplus >= 201103L
232 #define __LONG_LONG_SUPPORTED
233 #ifndef __STDC_LIMIT_MACROS
234 #define __STDC_LIMIT_MACROS
236 #ifndef __STDC_CONSTANT_MACROS
237 #define __STDC_CONSTANT_MACROS
242 * GNU C version 2.96 adds explicit branch prediction so that
243 * the CPU back-end can hint the processor and also so that
244 * code blocks can be reordered such that the predicted path
245 * sees a more linear flow, thus improving cache behavior, etc.
247 * The following two macros provide us with a way to utilize this
248 * compiler feature. Use __predict_true() if you expect the expression
249 * to evaluate to true, and __predict_false() if you expect the
250 * expression to evaluate to false.
252 * A few notes about usage:
254 * * Generally, __predict_false() error condition checks (unless
255 * you have some _strong_ reason to do otherwise, in which case
256 * document it), and/or __predict_true() `no-error' condition
257 * checks, assuming you want to optimize for the no-error case.
259 * * Other than that, if you don't know the likelihood of a test
260 * succeeding from empirical or other `hard' evidence, don't
263 * * These are meant to be used in places that are run `a lot'.
264 * It is wasteful to make predictions in code that is run
265 * seldomly (e.g. at subsystem initialization time) as the
266 * basic block reordering that this affects can often generate
269 #if __GNUC_PREREQ__(2, 96)
270 #define __predict_true(exp) __builtin_expect((exp), 1)
271 #define __predict_false(exp) __builtin_expect((exp), 0)
273 #define __predict_true(exp) (exp)
274 #define __predict_false(exp) (exp)
278 * GCC 2.95 and later provides `__restrict' as an extention to C90 to support
279 * the C99-specific `restrict' type qualifier. We happen to use `__restrict'
280 * as a way to define the `restrict' type qualifier without disturbing older
281 * software that is unaware of C99 keywords.
283 #if !__GNUC_PREREQ__(2, 95)
284 #if __STDC_VERSION__ < 199901
287 #define __restrict restrict
292 * Compiler-dependent macros to declare that functions take printf-like
293 * or scanf-like arguments. They are null except for versions of gcc
294 * that are known to support the features properly (old versions of gcc-2
295 * didn't permit keeping the keywords out of the application namespace).
297 * The printf0like macro for GCC 2 uses DragonFly specific compiler extensions.
299 #if !__GNUC_PREREQ__(2, 7)
300 #define __printflike(fmtarg, firstvararg)
301 #define __scanflike(fmtarg, firstvararg)
302 #define __printf0like(fmtarg, firstvararg)
303 #define __format_arg(fmtarg)
304 #define __strfmonlike(fmtarg, firstvararg)
305 #define __strftimelike(fmtarg, firstvararg)
307 #elif __GNUC_PREREQ__(3, 0)
308 #define __printflike(fmtarg, firstvararg) \
309 __attribute__((__nonnull__(fmtarg), \
310 __format__ (__printf__, fmtarg, firstvararg)))
311 #define __printf0like(fmtarg, firstvararg) \
312 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
313 #define __scanflike(fmtarg, firstvararg) \
314 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
315 #define __format_arg(fmtarg) \
316 __attribute__((__format_arg__ (fmtarg)))
317 #define __strfmonlike(fmtarg, firstvararg) \
318 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
319 #define __strftimelike(fmtarg, firstvararg) \
320 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
323 #define __printflike(fmtarg, firstvararg) \
324 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
325 #define __printf0like(fmtarg, firstvararg) \
326 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
327 #define __scanflike(fmtarg, firstvararg) \
328 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
329 #define __format_arg(fmtarg) \
330 __attribute__((__format_arg__ (fmtarg)))
331 #define __strfmonlike(fmtarg, firstvararg) \
332 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
333 #define __strftimelike(fmtarg, firstvararg) \
334 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
338 #if !__GNUC_PREREQ__(3, 0)
339 #define __ARRAY_ZERO 0
344 #if __GNUC_PREREQ__(4, 0)
345 #define __dso_public __attribute__((__visibility__("default")))
346 #define __dso_hidden __attribute__((__visibility__("hidden")))
353 * A convenient constructor macro, GCC 4.3.0 added priority support to
354 * constructors, provide a compatible interface for both.
356 #if __GNUC_PREREQ__(4, 3)
357 #define __constructor(prio) __attribute__((constructor(prio)))
359 #define __constructor(prio) __attribute__((constructor))
363 * Handy GCC based macros:
367 * The __cachealign macro can be used for cache line aligning structures
368 * of small to medium size. It aligns the particular structure or
369 * storage type to a system default cache line alignment, thus giving us
370 * a much more better cache utilization by making the hardware work at
371 * its best burst speeds.
375 * The __usereg macro can/should be used when a function contains
376 * arguments not more than 3. It can be very useful to us due to the
377 * message-passing nature of the kernel.
379 * !!NOTE - USAGE INFORMATION!!
381 * The __cachealign macro should not be used for data structures that are
382 * as big struct proc, struct vnode, struct thread, and other structs which
383 * are as big as them; simply because it will be useless in that case.
385 * The __usereg macro should be used whenever possible, i.e., when a function
386 * does not exceed more than 3 arguments, and should not be used for vararg
389 * In other words, AVOID MISUSE OF THESE MACROS. :-)
392 #define __cachealign __attribute__((__aligned__(__VM_CACHELINE_SIZE)))
393 #define __usereg __attribute__((__regparm__(3)))
400 #define __strong_reference(sym,aliassym) \
401 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)));
402 #define __weak_reference(sym,alias) \
403 __asm__(".weak " #alias); \
404 __asm__(".equ " #alias ", " #sym)
405 #define __warn_references(sym,msg) \
406 __asm__(".section .gnu.warning." #sym); \
407 __asm__(".asciz \"" msg "\""); \
409 #endif /* __GNUC__ */
411 #if defined(__GNUC__)
412 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
416 #define __RCSID(s) __IDSTRING(rcsid,s)
419 #ifndef __RCSID_SOURCE
420 #define __RCSID_SOURCE(s) __IDSTRING(rcsid_source,s)
424 #define __COPYRIGHT(s) __IDSTRING(copyright,s)
428 #define __DECONST(type, var) ((type)(uintptr_t)(const void *)(var))
432 #define __DEVOLATILE(type, var) ((type)(uintptr_t)(volatile void *)(var))
436 #define __DEQUALIFY(type, var) ((type)(uintptr_t)(const volatile void *)(var))
440 * Keywords added in C11.
443 #if !__GNUC_PREREQ__(2, 95)
444 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
448 * Keywords added in C11.
451 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
453 #if !__has_extension(c_alignas)
454 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
455 __has_extension(cxx_alignas)
456 #define _Alignas(x) alignas(x)
458 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
459 #define _Alignas(x) __aligned(x)
463 #if defined(__cplusplus) && __cplusplus >= 201103L
464 #define _Alignof(x) alignof(x)
466 #define _Alignof(x) __alignof(x)
469 #define _Noreturn __dead2
471 #if !__has_extension(c_static_assert)
472 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
473 __has_extension(cxx_static_assert)
474 #define _Static_assert(x, y) static_assert(x, y)
475 #elif !__GNUC_PREREQ__(4, 6)
476 #define _Static_assert(x, y) struct __hack
478 #define CTASSERT(x) _CTASSERT(x, __LINE__)
479 #define _CTASSERT(x, y) __CTASSERT(x, y)
480 #define __CTASSERT(x, y) typedef char __assert ## y[(x) ? 1 : -1]
485 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
487 #if defined(_KERNEL) && !defined(CTASSERT)
488 #define CTASSERT(x) _Static_assert(x, \
489 "compile-time assertion failed")
493 * Emulation of C11 _Generic(). Unlike the previously defined C11
494 * keywords, it is not possible to implement this using exactly the same
495 * syntax. Therefore implement something similar under the name
496 * __generic(). Unlike _Generic(), this macro can only distinguish
497 * between a single type, so it requires nested invocations to
498 * distinguish multiple cases.
501 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
502 #define __generic(expr, t, yes, no) \
503 _Generic(expr, t: yes, default: no)
504 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
505 #define __generic(expr, t, yes, no) \
506 __builtin_choose_expr( \
507 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
511 * POSIX.1 requires that the macros we test be defined before any standard
512 * header file is included.
514 * Here's a quick run-down of the versions:
515 * defined(_POSIX_SOURCE) 1003.1-1988
516 * _POSIX_C_SOURCE == 1 1003.1-1990
517 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
518 * _POSIX_C_SOURCE == 199309 1003.1b-1993
519 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
520 * and the omnibus ISO/IEC 9945-1: 1996
521 * _POSIX_C_SOURCE == 200112 1003.1-2001
522 * _POSIX_C_SOURCE == 200809 1003.1-2008
524 * In addition, the X/Open Portability Guide, which is now the Single UNIX
525 * Specification, defines a feature-test macro which indicates the version of
526 * that specification, and which subsumes _POSIX_C_SOURCE.
528 * Our macros begin with two underscores to avoid namespace screwage.
532 * If no special macro was specified, make the DragonFly extensions
533 * available. Also make them available when requested so.
535 #if (!defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE) && \
536 !defined(_ANSI_SOURCE) && !defined(_C99_SOURCE)) || \
537 defined(_DRAGONFLY_SOURCE) || defined(_NETBSD_SOURCE)
538 #define __DF_VISIBLE 1
540 #define __DF_VISIBLE 0
543 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
544 #if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 1
545 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
546 #define _POSIX_C_SOURCE 199009
549 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
550 #if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 2
551 #undef _POSIX_C_SOURCE
552 #define _POSIX_C_SOURCE 199209
555 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
557 #if _XOPEN_SOURCE - 0 >= 700
558 #define __XSI_VISIBLE 700
559 #undef _POSIX_C_SOURCE
560 #define _POSIX_C_SOURCE 200809
561 #elif _XOPEN_SOURCE - 0 >= 600
562 #define __XSI_VISIBLE 600
563 #undef _POSIX_C_SOURCE
564 #define _POSIX_C_SOURCE 200112
565 #elif _XOPEN_SOURCE - 0 >= 500
566 #define __XSI_VISIBLE 500
567 #undef _POSIX_C_SOURCE
568 #define _POSIX_C_SOURCE 199506
573 * Deal with all versions of POSIX. The ordering relative to the tests above is
576 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
577 #define _POSIX_C_SOURCE 198808
579 #ifdef _POSIX_C_SOURCE
580 #if (_POSIX_C_SOURCE - 0) >= 200809
581 #define __POSIX_VISIBLE 200809
582 #define __ISO_C_VISIBLE 1999
583 #elif (_POSIX_C_SOURCE - 0) >= 200112
584 #define __POSIX_VISIBLE 200112
585 #define __ISO_C_VISIBLE 1999
586 #elif (_POSIX_C_SOURCE - 0) >= 199506
587 #define __POSIX_VISIBLE 199506
588 #define __ISO_C_VISIBLE 1990
589 #elif (_POSIX_C_SOURCE - 0) >= 199309
590 #define __POSIX_VISIBLE 199309
591 #define __ISO_C_VISIBLE 1990
592 #elif (_POSIX_C_SOURCE - 0) >= 199209
593 #define __POSIX_VISIBLE 199209
594 #define __ISO_C_VISIBLE 1990
595 #elif (_POSIX_C_SOURCE - 0) >= 199009
596 #define __POSIX_VISIBLE 199009
597 #define __ISO_C_VISIBLE 1990
599 #define __POSIX_VISIBLE 198808
600 #define __ISO_C_VISIBLE 0
601 #endif /* _POSIX_C_SOURCE */
604 * Deal with _ANSI_SOURCE:
605 * If it is defined, and no other compilation environment is explicitly
606 * requested, then define our internal feature-test macros to zero. This
607 * makes no difference to the preprocessor (undefined symbols in preprocessing
608 * expressions are defined to have value zero), but makes it more convenient for
609 * a test program to print out the values.
611 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
612 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
613 * environment (and in fact we will never get here).
615 #ifdef _ANSI_SOURCE /* Hide almost everything. */
616 #define __POSIX_VISIBLE 0
617 #define __XSI_VISIBLE 0
618 #define __BSD_VISIBLE 0
619 #define __ISO_C_VISIBLE 1990
620 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
621 #define __POSIX_VISIBLE 0
622 #define __XSI_VISIBLE 0
623 #define __BSD_VISIBLE 0
624 #define __ISO_C_VISIBLE 1999
625 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
626 #define __POSIX_VISIBLE 0
627 #define __XSI_VISIBLE 0
628 #define __BSD_VISIBLE 0
629 #define __ISO_C_VISIBLE 2011
630 #else /* Default environment: show everything. */
631 #define __POSIX_VISIBLE 200809
632 #define __XSI_VISIBLE 700
633 #define __BSD_VISIBLE 1
634 #define __ISO_C_VISIBLE 2011
639 * GLOBL macro exists to preserve __start_set_* and __stop_set_* sections
640 * of kernel modules which are discarded from binutils 2.17.50+ otherwise.
643 #define __GLOBL1(sym) __asm__(".globl " #sym)
644 #define __GLOBL(sym) __GLOBL1(sym)
647 * Ignore the rcs id of a source file.
651 #define __FBSDID(s) struct __hack
655 #define __RCSID(s) struct __hack
658 #ifndef __RCSID_SOURCE
659 #define __RCSID_SOURCE(s) struct __hack
663 #define __SCCSID(s) struct __hack
667 #define __COPYRIGHT(s) struct __hack
670 #endif /* !_SYS_CDEFS_H_ */