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. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
37 * $FreeBSD: src/sys/sys/cdefs.h,v 1.28.2.8 2002/09/18 04:05:13 mikeh Exp $
44 * Testing against Clang-specific extensions.
47 #ifndef __has_extension
48 #define __has_extension __has_feature
51 #define __has_feature(x) 0
54 #define __has_include(x) 0
57 #define __has_builtin(x) 0
61 * Macro to test if we are using a specific version of gcc or later.
63 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
64 #define __GNUC_PREREQ__(ma, mi) \
65 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
67 #define __GNUC_PREREQ__(ma, mi) 0
70 #if defined(__cplusplus)
71 #if __GNUC_PREREQ__(4, 0)
72 #define __BEGIN_DECLS _Pragma("GCC visibility push(default)") extern "C" {
73 #define __END_DECLS } _Pragma("GCC visibility pop")
75 #define __BEGIN_DECLS extern "C" {
84 * The __VM_CACHELINE_SIZE macro defines the common cache line alignment
85 * size that can be found across most recent and somewhat latest Intel
86 * hardware, i.e. L1 cache sizes etc.
88 * If needed, this value can be TUNED. Suitable values for this macro
89 * are 32, 64 and 128 bytes. The unit of measurement for this macro is
92 * XXX: This macro and related macros will eventually move to a MD
93 * header, but currently, we do need such a hierarchy.
95 #define __VM_CACHELINE_SIZE 64
96 #define __VM_CACHELINE_MASK (__VM_CACHELINE_SIZE - 1)
97 #define __VM_CACHELINE_ALIGN(n) \
98 (((n) + __VM_CACHELINE_MASK) & ~__VM_CACHELINE_MASK)
101 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
102 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
103 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
104 * mode -- there must be no spaces between its arguments, and for nested
105 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
106 * concatenate double-quoted strings produced by the __STRING macro, but
107 * this only works with ANSI C.
109 * __XSTRING is like __STRING, but it expands any macros in its argument
110 * first. It is only available with ANSI C.
112 #if defined(__STDC__) || defined(__cplusplus)
113 #define __P(protos) protos /* full-blown ANSI C */
114 #define __CONCAT1(x,y) x ## y
115 #define __CONCAT(x,y) __CONCAT1(x,y)
116 #define __STRING(x) #x /* stringify without expanding x */
117 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
119 #define __const const /* define reserved names to standard */
120 #define __signed signed
121 #define __volatile volatile
122 #if defined(__cplusplus)
123 #define __inline inline /* convert to C++ keyword */
126 #define __inline /* delete GCC keyword */
127 #endif /* !__GNUC__ */
128 #endif /* !__cplusplus */
130 #else /* !(__STDC__ || __cplusplus) */
131 #define __P(protos) () /* traditional C preprocessor */
132 #define __CONCAT(x,y) x/**/y
133 #define __STRING(x) "x"
136 #define __const /* delete pseudo-ANSI C keywords */
141 * In non-ANSI C environments, new programs will want ANSI-only C keywords
142 * deleted from the program and old programs will want them left alone.
143 * When using a compiler other than gcc, programs using the ANSI C keywords
144 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
145 * When using "gcc -traditional", we assume that this is the intent; if
146 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
148 #ifndef NO_ANSI_KEYWORDS
149 #define const /* delete ANSI C keywords */
153 #endif /* !NO_ANSI_KEYWORDS */
154 #endif /* !__GNUC__ */
155 #endif /* !(__STDC__ || __cplusplus) */
158 * Compiler-dependent macros to help declare dead (non-returning) and
159 * pure (no side effects) functions, and unused variables. They are
160 * null except for versions of gcc that are known to support the features
161 * properly (old versions of gcc-2 supported the dead and pure features
162 * in a different (wrong) way).
173 #define __always_inline
178 #if !__GNUC_PREREQ__(2, 7)
184 #if __GNUC_PREREQ__(2, 7)
185 #define __dead2 __attribute__((__noreturn__))
186 #define __pure2 __attribute__((__const__))
187 #define __unused __attribute__((__unused__))
188 #define __packed __attribute__((__packed__))
189 #define __aligned(x) __attribute__((__aligned__(x)))
190 #define __section(x) __attribute__((__section__(x)))
193 #if __GNUC_PREREQ__(2, 96)
194 #define __pure __attribute__((__pure__))
196 #define __pure __pure2
199 #if __GNUC_PREREQ__(3, 1)
200 #define __always_inline __attribute__((__always_inline__))
201 #define __noinline __attribute__((__noinline__))
203 #define __always_inline
207 #if __GNUC_PREREQ__(3, 3)
208 #define __nonnull(x) __attribute__((__nonnull__(x)))
209 #define __used __attribute__((__used__))
212 #define __used __unused
217 #if !__GNUC_PREREQ__(2, 7) && __STDC_VERSION < 199901
218 #define __func__ NULL
221 #if (__GNUC_PREREQ__(2, 0) && !defined(__STRICT_ANSI)) || \
222 __STDC_VERSION__ >= 199901
223 #define __LONG_LONG_SUPPORTED
227 * GNU C version 2.96 adds explicit branch prediction so that
228 * the CPU back-end can hint the processor and also so that
229 * code blocks can be reordered such that the predicted path
230 * sees a more linear flow, thus improving cache behavior, etc.
232 * The following two macros provide us with a way to utilize this
233 * compiler feature. Use __predict_true() if you expect the expression
234 * to evaluate to true, and __predict_false() if you expect the
235 * expression to evaluate to false.
237 * A few notes about usage:
239 * * Generally, __predict_false() error condition checks (unless
240 * you have some _strong_ reason to do otherwise, in which case
241 * document it), and/or __predict_true() `no-error' condition
242 * checks, assuming you want to optimize for the no-error case.
244 * * Other than that, if you don't know the likelihood of a test
245 * succeeding from empirical or other `hard' evidence, don't
248 * * These are meant to be used in places that are run `a lot'.
249 * It is wasteful to make predictions in code that is run
250 * seldomly (e.g. at subsystem initialization time) as the
251 * basic block reordering that this affects can often generate
254 #if __GNUC_PREREQ__(2, 96)
255 #define __predict_true(exp) __builtin_expect((exp), 1)
256 #define __predict_false(exp) __builtin_expect((exp), 0)
258 #define __predict_true(exp) (exp)
259 #define __predict_false(exp) (exp)
263 * GCC 2.95 and later provides `__restrict' as an extention to C90 to support
264 * the C99-specific `restrict' type qualifier. We happen to use `__restrict'
265 * as a way to define the `restrict' type qualifier without disturbing older
266 * software that is unaware of C99 keywords.
268 #if !__GNUC_PREREQ__(2, 95)
269 #if __STDC_VERSION__ < 199901
272 #define __restrict restrict
277 * Compiler-dependent macros to declare that functions take printf-like
278 * or scanf-like arguments. They are null except for versions of gcc
279 * that are known to support the features properly (old versions of gcc-2
280 * didn't permit keeping the keywords out of the application namespace).
282 * The printf0like macro for GCC 2 uses DragonFly specific compiler extensions.
284 #if !__GNUC_PREREQ__(2, 7)
285 #define __printflike(fmtarg, firstvararg)
286 #define __scanflike(fmtarg, firstvararg)
287 #define __printf0like(fmtarg, firstvararg)
288 #define __format_arg(fmtarg)
289 #elif __GNUC_PREREQ__(3, 0)
290 #define __printflike(fmtarg, firstvararg) \
291 __attribute__((__nonnull__(fmtarg), \
292 __format__ (__printf__, fmtarg, firstvararg)))
293 #define __printf0like(fmtarg, firstvararg) \
294 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
295 #define __scanflike(fmtarg, firstvararg) \
296 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
297 #define __format_arg(fmtarg) \
298 __attribute__((__format_arg__ (fmtarg)))
301 #define __printflike(fmtarg, firstvararg) \
302 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
303 #define __printf0like(fmtarg, firstvararg) \
304 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
305 #define __scanflike(fmtarg, firstvararg) \
306 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
307 #define __format_arg(fmtarg) \
308 __attribute__((__format_arg__ (fmtarg)))
312 #if !__GNUC_PREREQ__(3, 0)
313 #define __ARRAY_ZERO 0
318 #if __GNUC_PREREQ__(4, 0)
319 #define __dso_public __attribute__((__visibility__("default")))
320 #define __dso_hidden __attribute__((__visibility__("hidden")))
327 * A convenient constructor macro, GCC 4.3.0 added priority support to
328 * constructors, provide a compatible interface for both.
330 #if __GNUC_PREREQ__(4, 3)
331 #define __constructor(prio) __attribute__((constructor(prio)))
333 #define __constructor(prio) __attribute__((constructor))
337 * Handy GCC based macros:
341 * The __cachealign macro can be used for cache line aligning structures
342 * of small to medium size. It aligns the particular structure or
343 * storage type to a system default cache line alignment, thus giving us
344 * a much more better cache utilization by making the hardware work at
345 * its best burst speeds.
349 * The __usereg macro can/should be used when a function contains
350 * arguments not more than 3. It can be very useful to us due to the
351 * message-passing nature of the kernel.
353 * !!NOTE - USAGE INFORMATION!!
355 * The __cachealign macro should not be used for data structures that are
356 * as big struct proc, struct vnode, struct thread, and other structs which
357 * are as big as them; simply because it will be useless in that case.
359 * The __usereg macro should be used whenever possible, i.e., when a function
360 * does not exceed more than 3 arguments, and should not be used for vararg
363 * In other words, AVOID MISUSE OF THESE MACROS. :-)
366 #define __cachealign __attribute__((__aligned__(__VM_CACHELINE_SIZE)))
367 #define __usereg __attribute__((__regparm__(3)))
374 #define __strong_reference(sym,aliassym) \
375 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)));
376 #define __weak_reference(sym,alias) \
377 __asm__(".weak " #alias); \
378 __asm__(".equ " #alias ", " #sym)
379 #define __warn_references(sym,msg) \
380 __asm__(".section .gnu.warning." #sym); \
381 __asm__(".asciz \"" msg "\""); \
383 #endif /* __GNUC__ */
385 #if defined(__GNUC__)
386 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
390 #define __RCSID(s) __IDSTRING(rcsid,s)
393 #ifndef __RCSID_SOURCE
394 #define __RCSID_SOURCE(s) __IDSTRING(rcsid_source,s)
398 #define __COPYRIGHT(s) __IDSTRING(copyright,s)
402 #define __DECONST(type, var) ((type)(uintptr_t)(const void *)(var))
406 #define __DEVOLATILE(type, var) ((type)(uintptr_t)(volatile void *)(var))
410 #define __DEQUALIFY(type, var) ((type)(uintptr_t)(const volatile void *)(var))
414 * Keywords added in C11.
417 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
419 #define _Noreturn __dead2
421 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
423 #if !__has_extension(c_static_assert)
424 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
425 __has_extension(cxx_static_assert)
426 #define _Static_assert(x, y) static_assert(x, y)
427 #elif !__GNUC_PREREQ__(4, 6)
428 #define _Static_assert(x, y) struct __hack
433 * Emulation of C11 _Generic(). Unlike the previously defined C11
434 * keywords, it is not possible to implement this using exactly the same
435 * syntax. Therefore implement something similar under the name
436 * __generic(). Unlike _Generic(), this macro can only distinguish
437 * between a single type, so it requires nested invocations to
438 * distinguish multiple cases.
441 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
442 #define __generic(expr, t, yes, no) \
443 _Generic(expr, t: yes, default: no)
444 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
445 #define __generic(expr, t, yes, no) \
446 __builtin_choose_expr( \
447 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
451 * The following definitions are an extension of the behavior originally
452 * implemented in <sys/_posix.h>, but with a different level of granularity.
453 * POSIX.1 requires that the macros we test be defined before any standard
454 * header file is included.
456 * Here's a quick run-down of the versions:
457 * defined(_POSIX_SOURCE) 1003.1-1988
458 * _POSIX_C_SOURCE == 1 1003.1-1990
459 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
460 * _POSIX_C_SOURCE == 199309 1003.1b-1993
461 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
462 * and the omnibus ISO/IEC 9945-1: 1996
463 * _POSIX_C_SOURCE == 200112 1003.1-2001
464 * _POSIX_C_SOURCE == 200809 1003.1-2008
466 * In addition, the X/Open Portability Guide, which is now the Single UNIX
467 * Specification, defines a feature-test macro which indicates the version of
468 * that specification, and which subsumes _POSIX_C_SOURCE.
470 * Our macros begin with two underscores to avoid namespace screwage.
474 * If no special macro was specified, make the DragonFly extensions
475 * available. Also make them available when requested so.
477 #if (!defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE) && \
478 !defined(_ANSI_SOURCE) && !defined(_C99_SOURCE)) || \
479 defined(_DRAGONFLY_SOURCE) || defined(_NETBSD_SOURCE)
480 #define __DF_VISIBLE 1
482 #define __DF_VISIBLE 0
485 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
486 #if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 1
487 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
488 #define _POSIX_C_SOURCE 199009
491 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
492 #if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 2
493 #undef _POSIX_C_SOURCE
494 #define _POSIX_C_SOURCE 199209
497 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
499 #if _XOPEN_SOURCE - 0 >= 700
500 #define __XSI_VISIBLE 700
501 #undef _POSIX_C_SOURCE
502 #define _POSIX_C_SOURCE 200809
503 #elif _XOPEN_SOURCE - 0 >= 600
504 #define __XSI_VISIBLE 600
505 #undef _POSIX_C_SOURCE
506 #define _POSIX_C_SOURCE 200112
507 #elif _XOPEN_SOURCE - 0 >= 500
508 #define __XSI_VISIBLE 500
509 #undef _POSIX_C_SOURCE
510 #define _POSIX_C_SOURCE 199506
515 * Deal with all versions of POSIX. The ordering relative to the tests above is
518 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
519 #define _POSIX_C_SOURCE 198808
521 #ifdef _POSIX_C_SOURCE
522 #if (_POSIX_C_SOURCE - 0) >= 200809
523 #define __POSIX_VISIBLE 200809
524 #define __ISO_C_VISIBLE 1999
525 #elif (_POSIX_C_SOURCE - 0) >= 200112
526 #define __POSIX_VISIBLE 200112
527 #define __ISO_C_VISIBLE 1999
528 #elif (_POSIX_C_SOURCE - 0) >= 199506
529 #define __POSIX_VISIBLE 199506
530 #define __ISO_C_VISIBLE 1990
531 #elif (_POSIX_C_SOURCE - 0) >= 199309
532 #define __POSIX_VISIBLE 199309
533 #define __ISO_C_VISIBLE 1990
534 #elif (_POSIX_C_SOURCE - 0) >= 199209
535 #define __POSIX_VISIBLE 199209
536 #define __ISO_C_VISIBLE 1990
537 #elif (_POSIX_C_SOURCE - 0) >= 199009
538 #define __POSIX_VISIBLE 199009
539 #define __ISO_C_VISIBLE 1990
541 #define __POSIX_VISIBLE 198808
542 #define __ISO_C_VISIBLE 0
543 #endif /* _POSIX_C_SOURCE */
546 * Deal with _ANSI_SOURCE:
547 * If it is defined, and no other compilation environment is explicitly
548 * requested, then define our internal feature-test macros to zero. This
549 * makes no difference to the preprocessor (undefined symbols in preprocessing
550 * expressions are defined to have value zero), but makes it more convenient for
551 * a test program to print out the values.
553 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
554 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
555 * environment (and in fact we will never get here).
557 #ifdef _ANSI_SOURCE /* Hide almost everything. */
558 #define __POSIX_VISIBLE 0
559 #define __XSI_VISIBLE 0
560 #define __BSD_VISIBLE 0
561 #define __ISO_C_VISIBLE 1990
562 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
563 #define __POSIX_VISIBLE 0
564 #define __XSI_VISIBLE 0
565 #define __BSD_VISIBLE 0
566 #define __ISO_C_VISIBLE 1999
567 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
568 #define __POSIX_VISIBLE 0
569 #define __XSI_VISIBLE 0
570 #define __BSD_VISIBLE 0
571 #define __ISO_C_VISIBLE 2011
572 #else /* Default environment: show everything. */
573 #define __POSIX_VISIBLE 200809
574 #define __XSI_VISIBLE 700
575 #define __BSD_VISIBLE 1
576 #define __ISO_C_VISIBLE 2011
581 * GLOBL macro exists to preserve __start_set_* and __stop_set_* sections
582 * of kernel modules which are discarded from binutils 2.17.50+ otherwise.
585 #define __GLOBL1(sym) __asm__(".globl " #sym)
586 #define __GLOBL(sym) __GLOBL1(sym)
588 #endif /* !_SYS_CDEFS_H_ */