kern.{post,pre}.mk: Clean up a bit.
[dragonfly.git] / sys / sys / cdefs.h
CommitLineData
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1/*
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Berkeley Software Design, Inc.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
2c64e990 16 * 3. Neither the name of the University nor the names of its contributors
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17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
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 $
34 */
35
36#ifndef _SYS_CDEFS_H_
37#define _SYS_CDEFS_H_
38
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39/*
40 * Testing against Clang-specific extensions.
41 */
bcbc8077 42#ifndef __has_attribute
43#define __has_attribute(x) 0
44#endif
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45#ifndef __has_extension
46#define __has_extension __has_feature
47#endif
48#ifndef __has_feature
49#define __has_feature(x) 0
50#endif
51#ifndef __has_include
52#define __has_include(x) 0
53#endif
54#ifndef __has_builtin
55#define __has_builtin(x) 0
56#endif
57
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58/*
59 * Macro to test if we are using a specific version of gcc or later.
60 */
43c9ef94 61#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
595ea270 62#define __GNUC_PREREQ__(ma, mi) \
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63 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
64#else
595ea270 65#define __GNUC_PREREQ__(ma, mi) 0
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66#endif
67
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68#if defined(__cplusplus)
69#if __GNUC_PREREQ__(4, 0)
70#define __BEGIN_DECLS _Pragma("GCC visibility push(default)") extern "C" {
71#define __END_DECLS } _Pragma("GCC visibility pop")
72#else
73#define __BEGIN_DECLS extern "C" {
74#define __END_DECLS }
75#endif
76#else
77#define __BEGIN_DECLS
78#define __END_DECLS
79#endif
80
f754816e 81/*
d9abbdda 82 * The __VM_CACHELINE_SIZE macro defines the common cache line alignment
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83 * size that can be found across most recent and somewhat latest Intel
84 * hardware, i.e. L1 cache sizes etc.
85 *
86 * If needed, this value can be TUNED. Suitable values for this macro
87 * are 32, 64 and 128 bytes. The unit of measurement for this macro is
88 * bytes.
a43eae19 89 *
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90 * XXX: This macro and related macros will eventually move to a MD
91 * header, but currently, we do need such a hierarchy.
92 */
ddca1582 93#define __VM_CACHELINE_SIZE 64
595ea270 94#define __VM_CACHELINE_MASK (__VM_CACHELINE_SIZE - 1)
ddca1582 95#define __VM_CACHELINE_ALIGN(n) \
583f14fd 96 (((n) + __VM_CACHELINE_MASK) & ~__VM_CACHELINE_MASK)
f754816e 97
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98/*
99 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
100 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
101 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
102 * mode -- there must be no spaces between its arguments, and for nested
103 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
104 * concatenate double-quoted strings produced by the __STRING macro, but
105 * this only works with ANSI C.
106 *
107 * __XSTRING is like __STRING, but it expands any macros in its argument
108 * first. It is only available with ANSI C.
109 */
110#if defined(__STDC__) || defined(__cplusplus)
111#define __P(protos) protos /* full-blown ANSI C */
112#define __CONCAT1(x,y) x ## y
113#define __CONCAT(x,y) __CONCAT1(x,y)
114#define __STRING(x) #x /* stringify without expanding x */
115#define __XSTRING(x) __STRING(x) /* expand x, then stringify */
116
117#define __const const /* define reserved names to standard */
118#define __signed signed
119#define __volatile volatile
120#if defined(__cplusplus)
121#define __inline inline /* convert to C++ keyword */
122#else
123#ifndef __GNUC__
124#define __inline /* delete GCC keyword */
125#endif /* !__GNUC__ */
126#endif /* !__cplusplus */
127
128#else /* !(__STDC__ || __cplusplus) */
129#define __P(protos) () /* traditional C preprocessor */
130#define __CONCAT(x,y) x/**/y
131#define __STRING(x) "x"
132
133#ifndef __GNUC__
134#define __const /* delete pseudo-ANSI C keywords */
135#define __inline
136#define __signed
137#define __volatile
138/*
139 * In non-ANSI C environments, new programs will want ANSI-only C keywords
140 * deleted from the program and old programs will want them left alone.
141 * When using a compiler other than gcc, programs using the ANSI C keywords
142 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
143 * When using "gcc -traditional", we assume that this is the intent; if
144 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
145 */
146#ifndef NO_ANSI_KEYWORDS
147#define const /* delete ANSI C keywords */
148#define inline
149#define signed
150#define volatile
151#endif /* !NO_ANSI_KEYWORDS */
152#endif /* !__GNUC__ */
153#endif /* !(__STDC__ || __cplusplus) */
154
155/*
156 * Compiler-dependent macros to help declare dead (non-returning) and
157 * pure (no side effects) functions, and unused variables. They are
158 * null except for versions of gcc that are known to support the features
159 * properly (old versions of gcc-2 supported the dead and pure features
160 * in a different (wrong) way).
161 */
f8406b33 162#define __weak_symbol __attribute__((__weak__))
dc62b251 163#if __GNUC_PREREQ__(2, 7)
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164#define __dead2 __attribute__((__noreturn__))
165#define __pure2 __attribute__((__const__))
166#define __unused __attribute__((__unused__))
9a7c65ce 167#define __packed __attribute__((__packed__))
168#define __aligned(x) __attribute__((__aligned__(x)))
169#define __section(x) __attribute__((__section__(x)))
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170#define __read_mostly __section(".data.read_mostly")
171#define __read_frequently __section(".data.read_frequently")
78831f77 172#define __exclusive_cache_line __aligned(__VM_CACHELINE_SIZE*2) \
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173 __section(".data.exclusive_cache_line")
174
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175#else
176#define __dead2
177#define __pure2
178#define __unused
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179#endif
180
74c78f9b 181#if __GNUC_PREREQ__(2, 96)
bcbc8077 182#define __malloclike __attribute__((__malloc__))
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183#define __pure __attribute__((__pure__))
184#else
bcbc8077 185#define __malloclike
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186#define __pure __pure2
187#endif
188
dc62b251 189#if __GNUC_PREREQ__(3, 1)
9a7c65ce 190#define __always_inline __attribute__((__always_inline__))
e0f95098 191#define __noinline __attribute__((__noinline__))
dc62b251 192#else
595ea270 193#define __always_inline
e0f95098 194#define __noinline
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195#endif
196
197#if __GNUC_PREREQ__(3, 3)
466b1c70 198#define __nonnull(...) __attribute__((__nonnull__(__VA_ARGS__)))
efb8080e 199#define __used __attribute__((__used__))
dc62b251 200#else
466b1c70 201#define __nonnull(...)
595ea270 202#define __used __unused
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203#endif
204
8db0c49d 205#if __GNUC_PREREQ__(3, 4)
206#define __heedresult __attribute__((__warn_unused_result__))
207#else
208#define __heedresult
209#endif
210
c18f110e 211#if __GNUC_PREREQ__(4, 1)
9a7c65ce 212#define __returns_twice __attribute__((__returns_twice__))
c18f110e 213#else
595ea270 214#define __returns_twice
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215#endif
216
bcbc8077 217#if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
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218#define __alloc_size(x) __attribute__((__alloc_size__(x)))
219#define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x)))
bcbc8077 220#else
221#define __alloc_size(x)
fc0e4e26 222#define __alloc_size2(n, x)
bcbc8077 223#endif
224
225#if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
226#define __alloc_align(x) __attribute__((__alloc_align__(x)))
227#else
228#define __alloc_align(x)
229#endif
230
74351cf4 231#if !__GNUC_PREREQ__(2, 7) && __STDC_VERSION__ < 199901
9a7c65ce 232#define __func__ NULL
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233#endif
234
d14a8cb8 235#if (__GNUC_PREREQ__(2, 0) && !defined(__STRICT_ANSI__)) || \
3d28a533 236 __STDC_VERSION__ >= 199901
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237#define __LONG_LONG_SUPPORTED
238#endif
239
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240/* C++11 exposes a load of C99 stuff */
241#if defined(__cplusplus) && __cplusplus >= 201103L
242#define __LONG_LONG_SUPPORTED
243#ifndef __STDC_LIMIT_MACROS
244#define __STDC_LIMIT_MACROS
245#endif
246#ifndef __STDC_CONSTANT_MACROS
247#define __STDC_CONSTANT_MACROS
248#endif
249#endif
250
9a7c65ce 251/*
252 * GCC 2.95 and later provides `__restrict' as an extension to C90 to support
253 * the C99-specific `restrict' type qualifier. We happen to use `__restrict'
254 * as a way to define the `restrict' type qualifier without disturbing older
255 * software that is unaware of C99 keywords.
256 */
257#if !__GNUC_PREREQ__(2, 95)
258#if __STDC_VERSION__ < 199901
259#define __restrict
260#else
261#define __restrict restrict
262#endif
263#endif
264
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265/*
266 * C99 allows to declare arrays as non-overlapping.
267 */
268#if __GNUC_PREREQ__(3, 1) && !defined(__GNUG__)
269#define __restrict_arr __restrict
270#else
271#ifdef __GNUC__
272#define __restrict_arr
273#else
274#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901
275#define __restrict_arr restrict
276#else
277#define __restrict_arr
278#endif
279#endif
280#endif
281
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282/*
283 * GNU C version 2.96 adds explicit branch prediction so that
284 * the CPU back-end can hint the processor and also so that
285 * code blocks can be reordered such that the predicted path
286 * sees a more linear flow, thus improving cache behavior, etc.
287 *
288 * The following two macros provide us with a way to utilize this
289 * compiler feature. Use __predict_true() if you expect the expression
290 * to evaluate to true, and __predict_false() if you expect the
291 * expression to evaluate to false.
292 *
293 * A few notes about usage:
294 *
295 * * Generally, __predict_false() error condition checks (unless
296 * you have some _strong_ reason to do otherwise, in which case
297 * document it), and/or __predict_true() `no-error' condition
298 * checks, assuming you want to optimize for the no-error case.
299 *
300 * * Other than that, if you don't know the likelihood of a test
301 * succeeding from empirical or other `hard' evidence, don't
302 * make predictions.
303 *
304 * * These are meant to be used in places that are run `a lot'.
305 * It is wasteful to make predictions in code that is run
306 * seldomly (e.g. at subsystem initialization time) as the
307 * basic block reordering that this affects can often generate
308 * larger code.
309 */
310#if __GNUC_PREREQ__(2, 96)
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311#define __predict_true(exp) __builtin_expect((exp), 1)
312#define __predict_false(exp) __builtin_expect((exp), 0)
ae0ec55c 313#else
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314#define __predict_true(exp) (exp)
315#define __predict_false(exp) (exp)
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316#endif
317
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318/*
319 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
320 * require it.
321 */
322#if __GNUC_PREREQ__(4, 1)
323#define __offsetof(type, field) __builtin_offsetof(type, field)
324#else
325#ifndef __cplusplus
326#define __offsetof(type, field) \
327 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
328#else
329#define __offsetof(type, field) \
330 (__offsetof__ (reinterpret_cast <__size_t> \
331 (&reinterpret_cast <const volatile char &> \
332 (static_cast<type *> (0)->field))))
333#endif
334#endif
335
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336/*
337 * Compiler-dependent macros to declare that functions take printf-like
338 * or scanf-like arguments. They are null except for versions of gcc
339 * that are known to support the features properly (old versions of gcc-2
340 * didn't permit keeping the keywords out of the application namespace).
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341 *
342 * The printf0like macro for GCC 2 uses DragonFly specific compiler extensions.
984263bc 343 */
3d28a533 344#if !__GNUC_PREREQ__(2, 7)
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345#define __printflike(fmtarg, firstvararg)
346#define __scanflike(fmtarg, firstvararg)
38139e70 347#define __printf0like(fmtarg, firstvararg)
e0f95098 348#define __format_arg(fmtarg)
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349#define __strfmonlike(fmtarg, firstvararg)
350#define __strftimelike(fmtarg, firstvararg)
351
3d28a533 352#elif __GNUC_PREREQ__(3, 0)
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353#define __printflike(fmtarg, firstvararg) \
354 __attribute__((__nonnull__(fmtarg), \
355 __format__ (__printf__, fmtarg, firstvararg)))
356#define __printf0like(fmtarg, firstvararg) \
357 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
358#define __scanflike(fmtarg, firstvararg) \
359 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
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360#define __format_arg(fmtarg) \
361 __attribute__((__format_arg__ (fmtarg)))
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362#define __strfmonlike(fmtarg, firstvararg) \
363 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
364#define __strftimelike(fmtarg, firstvararg) \
365 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
38139e70 366
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367#else
368#define __printflike(fmtarg, firstvararg) \
369 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
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370#define __printf0like(fmtarg, firstvararg) \
371 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
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372#define __scanflike(fmtarg, firstvararg) \
373 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
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374#define __format_arg(fmtarg) \
375 __attribute__((__format_arg__ (fmtarg)))
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376#define __strfmonlike(fmtarg, firstvararg) \
377 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
378#define __strftimelike(fmtarg, firstvararg) \
379 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
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380#endif
381
3d28a533 382#if !__GNUC_PREREQ__(3, 0)
595ea270 383#define __ARRAY_ZERO 0
18ba5b61 384#else
595ea270 385#define __ARRAY_ZERO
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386#endif
387
25fffb38 388#if __GNUC_PREREQ__(4, 0)
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389#define __dso_public __attribute__((__visibility__("default")))
390#define __dso_hidden __attribute__((__visibility__("hidden")))
25fffb38 391#else
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392#define __dso_public
393#define __dso_hidden
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394#endif
395
754d5cac 396/*
2ea04d5f 397 * A convenient constructor macro, GCC 4.3.0 added priority support to
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398 * constructors, provide a compatible interface for both.
399 */
400#if __GNUC_PREREQ__(4, 3)
9a7c65ce 401#define __constructor(prio) __attribute__((constructor(prio)))
754d5cac 402#else
9a7c65ce 403#define __constructor(prio) __attribute__((constructor))
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404#endif
405
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406/*
407 * Handy GCC based macros:
408 *
409 * __cachealign:
a43eae19 410 *
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411 * The __cachealign macro can be used for cache line aligning structures
412 * of small to medium size. It aligns the particular structure or
413 * storage type to a system default cache line alignment, thus giving us
414 * a much more better cache utilization by making the hardware work at
415 * its best burst speeds.
416 *
417 * __usereg:
a43eae19 418 *
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419 * The __usereg macro can/should be used when a function contains
420 * arguments not more than 3. It can be very useful to us due to the
421 * message-passing nature of the kernel.
422 *
423 * !!NOTE - USAGE INFORMATION!!
424 *
425 * The __cachealign macro should not be used for data structures that are
426 * as big struct proc, struct vnode, struct thread, and other structs which
427 * are as big as them; simply because it will be useless in that case.
428 *
429 * The __usereg macro should be used whenever possible, i.e., when a function
430 * does not exceed more than 3 arguments, and should not be used for vararg
431 * type functions.
432 *
433 * In other words, AVOID MISUSE OF THESE MACROS. :-)
434 */
435#ifdef __GNUC__
d9abbdda 436#define __cachealign __attribute__((__aligned__(__VM_CACHELINE_SIZE)))
9a7c65ce 437#define __usereg __attribute__((__regparm__(3)))
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438#else
439#define __cachealign
440#define __usereg
441#endif
442
984263bc 443#ifdef __GNUC__
595ea270 444#define __strong_reference(sym,aliassym) \
9a7c65ce 445 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
f8406b33 446#define __weak_reference(sym,aliassym) \
447 __strong_reference(sym,aliassym) __attribute__ ((__weak__))
448#define __weak_reference_asm(sym,alias) \
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449 __asm__(".weak " #alias); \
450 __asm__(".equ " #alias ", " #sym)
451#define __warn_references(sym,msg) \
452 __asm__(".section .gnu.warning." #sym); \
453 __asm__(".asciz \"" msg "\""); \
454 __asm__(".previous")
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455#define __sym_compat(sym,impl,verid) \
456 __asm__(".symver " #impl ", " #sym "@" #verid)
457#define __sym_default(sym,impl,verid) \
458 __asm__(".symver " #impl ", " #sym "@@@" #verid)
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459#endif /* __GNUC__ */
460
aa8d5dcb 461#if defined(__GNUC__)
984263bc 462#define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
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463#endif
464
465#ifndef __RCSID
7217e995 466#define __RCSID(s) struct __hack
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467#endif
468
984263bc 469#ifndef __RCSID_SOURCE
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470#define __RCSID_SOURCE(s) struct __hack
471#endif
472
473#ifndef __SCCSID
474#define __SCCSID(s) struct __hack
475#endif
476
477#ifndef __FBSDID
478#define __FBSDID(s) struct __hack
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479#endif
480
481#ifndef __COPYRIGHT
7217e995 482#define __COPYRIGHT(s) struct __hack
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483#endif
484
8a59902d 485#ifndef __DECONST
a43eae19 486#define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
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487#endif
488
489#ifndef __DEVOLATILE
a43eae19 490#define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
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491#endif
492
493#ifndef __DEQUALIFY
a43eae19 494#define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
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495#endif
496
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497/*
498 * Keywords added in C11.
499 */
500
501#if !__GNUC_PREREQ__(2, 95)
502#define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
503#endif
504
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505#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
506
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507#if !__has_extension(c_alignas)
508#if (defined(__cplusplus) && __cplusplus >= 201103L) || \
509 __has_extension(cxx_alignas)
510#define _Alignas(x) alignas(x)
511#else
512/* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
513#define _Alignas(x) __aligned(x)
514#endif
515#endif
c3e32db9 516
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517#if defined(__cplusplus) && __cplusplus >= 201103L
518#define _Alignof(x) alignof(x)
519#else
520#define _Alignof(x) __alignof(x)
521#endif
522
a04bd7b8 523#if !defined(_Noreturn)
787c3580 524#define _Noreturn __dead2
a04bd7b8 525#endif
c3e32db9 526
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527#if !__has_extension(c_static_assert)
528#if (defined(__cplusplus) && __cplusplus >= 201103L) || \
529 __has_extension(cxx_static_assert)
530#define _Static_assert(x, y) static_assert(x, y)
91c5bb9b 531#elif !__GNUC_PREREQ__(4, 6)
c5fedb6c 532#define _Static_assert(x, y) struct __hack
85325fa5 533#ifdef _KERNEL
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534#define CTASSERT(x) _CTASSERT(x, __LINE__)
535#define _CTASSERT(x, y) __CTASSERT(x, y)
536#define __CTASSERT(x, y) typedef char __assert ## y[(x) ? 1 : -1]
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537#endif
538#endif
85325fa5 539#endif
31c7f3d7 540
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541#endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
542
85325fa5 543#if defined(_KERNEL) && !defined(CTASSERT)
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544#define CTASSERT(x) _Static_assert(x, \
545 "compile-time assertion failed")
c5fedb6c 546#endif
c5fedb6c 547
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548/*
549 * Emulation of C11 _Generic(). Unlike the previously defined C11
550 * keywords, it is not possible to implement this using exactly the same
551 * syntax. Therefore implement something similar under the name
552 * __generic(). Unlike _Generic(), this macro can only distinguish
553 * between a single type, so it requires nested invocations to
554 * distinguish multiple cases.
555 */
556
557#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
558#define __generic(expr, t, yes, no) \
559 _Generic(expr, t: yes, default: no)
560#elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
561#define __generic(expr, t, yes, no) \
562 __builtin_choose_expr( \
563 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
564#endif
565
984263bc 566/*-
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567 * POSIX.1 requires that the macros we test be defined before any standard
568 * header file is included.
569 *
570 * Here's a quick run-down of the versions:
571 * defined(_POSIX_SOURCE) 1003.1-1988
572 * _POSIX_C_SOURCE == 1 1003.1-1990
573 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
574 * _POSIX_C_SOURCE == 199309 1003.1b-1993
575 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
576 * and the omnibus ISO/IEC 9945-1: 1996
577 * _POSIX_C_SOURCE == 200112 1003.1-2001
ae2ee8ee 578 * _POSIX_C_SOURCE == 200809 1003.1-2008
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579 *
580 * In addition, the X/Open Portability Guide, which is now the Single UNIX
581 * Specification, defines a feature-test macro which indicates the version of
582 * that specification, and which subsumes _POSIX_C_SOURCE.
583 *
584 * Our macros begin with two underscores to avoid namespace screwage.
585 */
586
587/* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
2c292fb2 588#if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 1
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589#undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
590#define _POSIX_C_SOURCE 199009
591#endif
592
593/* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
2c292fb2 594#if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE - 0) == 2
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595#undef _POSIX_C_SOURCE
596#define _POSIX_C_SOURCE 199209
597#endif
598
599/* Deal with various X/Open Portability Guides and Single UNIX Spec. */
600#ifdef _XOPEN_SOURCE
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601#if _XOPEN_SOURCE - 0 >= 700
602#define __XSI_VISIBLE 700
603#undef _POSIX_C_SOURCE
604#define _POSIX_C_SOURCE 200809
605#elif _XOPEN_SOURCE - 0 >= 600
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606#define __XSI_VISIBLE 600
607#undef _POSIX_C_SOURCE
608#define _POSIX_C_SOURCE 200112
609#elif _XOPEN_SOURCE - 0 >= 500
610#define __XSI_VISIBLE 500
611#undef _POSIX_C_SOURCE
612#define _POSIX_C_SOURCE 199506
613#endif
614#endif
615
616/*
617 * Deal with all versions of POSIX. The ordering relative to the tests above is
618 * important.
619 */
620#if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
621#define _POSIX_C_SOURCE 198808
622#endif
623#ifdef _POSIX_C_SOURCE
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624#if (_POSIX_C_SOURCE - 0) >= 200809
625#define __POSIX_VISIBLE 200809
626#define __ISO_C_VISIBLE 1999
627#elif (_POSIX_C_SOURCE - 0) >= 200112
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628#define __POSIX_VISIBLE 200112
629#define __ISO_C_VISIBLE 1999
2c292fb2 630#elif (_POSIX_C_SOURCE - 0) >= 199506
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631#define __POSIX_VISIBLE 199506
632#define __ISO_C_VISIBLE 1990
2c292fb2 633#elif (_POSIX_C_SOURCE - 0) >= 199309
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634#define __POSIX_VISIBLE 199309
635#define __ISO_C_VISIBLE 1990
2c292fb2 636#elif (_POSIX_C_SOURCE - 0) >= 199209
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637#define __POSIX_VISIBLE 199209
638#define __ISO_C_VISIBLE 1990
2c292fb2 639#elif (_POSIX_C_SOURCE - 0) >= 199009
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640#define __POSIX_VISIBLE 199009
641#define __ISO_C_VISIBLE 1990
642#else
643#define __POSIX_VISIBLE 198808
644#define __ISO_C_VISIBLE 0
645#endif /* _POSIX_C_SOURCE */
646#else
647/*-
648 * Deal with _ANSI_SOURCE:
649 * If it is defined, and no other compilation environment is explicitly
650 * requested, then define our internal feature-test macros to zero. This
651 * makes no difference to the preprocessor (undefined symbols in preprocessing
652 * expressions are defined to have value zero), but makes it more convenient for
653 * a test program to print out the values.
654 *
655 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
656 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
657 * environment (and in fact we will never get here).
658 */
9a7c65ce 659#if defined(_ANSI_SOURCE) /* Hide almost everything. */
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660#define __POSIX_VISIBLE 0
661#define __XSI_VISIBLE 0
662#define __BSD_VISIBLE 0
663#define __ISO_C_VISIBLE 1990
2470bb80 664#define __EXT1_VISIBLE 0
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665#elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
666#define __POSIX_VISIBLE 0
667#define __XSI_VISIBLE 0
668#define __BSD_VISIBLE 0
669#define __ISO_C_VISIBLE 1999
2470bb80 670#define __EXT1_VISIBLE 0
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671#elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
672#define __POSIX_VISIBLE 0
673#define __XSI_VISIBLE 0
674#define __BSD_VISIBLE 0
675#define __ISO_C_VISIBLE 2011
2470bb80 676#define __EXT1_VISIBLE 0
984263bc 677#else /* Default environment: show everything. */
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678#define __POSIX_VISIBLE 200809
679#define __XSI_VISIBLE 700
984263bc 680#define __BSD_VISIBLE 1
0d5acd74 681#define __ISO_C_VISIBLE 2011
2470bb80 682#define __EXT1_VISIBLE 1
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683#endif
684#endif
685
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686/* User override __EXT1_VISIBLE */
687#if defined(__STDC_WANT_LIB_EXT1__)
688#undef __EXT1_VISIBLE
689#if __STDC_WANT_LIB_EXT1__
690#define __EXT1_VISIBLE 1
691#else
692#define __EXT1_VISIBLE 0
693#endif
694#endif /* __STDC_WANT_LIB_EXT1__ */
695
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696#ifndef __BSD_VISIBLE
697#define __BSD_VISIBLE 0
698#endif
699#ifndef __EXT1_VISIBLE
700#define __EXT1_VISIBLE 0
701#endif
702
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703/*
704 * GLOBL macro exists to preserve __start_set_* and __stop_set_* sections
705 * of kernel modules which are discarded from binutils 2.17.50+ otherwise.
706 */
707
708#define __GLOBL1(sym) __asm__(".globl " #sym)
709#define __GLOBL(sym) __GLOBL1(sym)
710
984263bc 711#endif /* !_SYS_CDEFS_H_ */