xref: /dragonfly/sys/sys/cdefs.h (revision 1d1731fa)
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.
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.
23  *
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
34  * SUCH DAMAGE.
35  *
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 $
38  * $DragonFly: src/sys/sys/cdefs.h,v 1.5 2003/08/27 17:13:22 hmp Exp $
39  */
40 
41 #ifndef	_SYS_CDEFS_H_
42 #define	_SYS_CDEFS_H_
43 
44 #if defined(__cplusplus)
45 #define	__BEGIN_DECLS	extern "C" {
46 #define	__END_DECLS	}
47 #else
48 #define	__BEGIN_DECLS
49 #define	__END_DECLS
50 #endif
51 
52 /*
53  * The VM_CACHELINE_SIZE macro defines the common cache line alignment
54  * size that can be found across most recent and somewhat latest Intel
55  * hardware, i.e. L1 cache sizes etc.
56  *
57  * If needed, this value can be TUNED.  Suitable values for this macro
58  * are 32, 64 and 128 bytes.  The unit of measurement for this macro is
59  * bytes.
60  *
61  * XXX: This macro and related macros will eventually move to a MD
62  * header, but currently, we do need such a hierarchy.
63  */
64 #define	VM_CACHELINE_SIZE	32
65 
66 /*
67  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
68  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
69  * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
70  * mode -- there must be no spaces between its arguments, and for nested
71  * __CONCAT's, all the __CONCAT's must be at the left.  __CONCAT can also
72  * concatenate double-quoted strings produced by the __STRING macro, but
73  * this only works with ANSI C.
74  *
75  * __XSTRING is like __STRING, but it expands any macros in its argument
76  * first.  It is only available with ANSI C.
77  */
78 #if defined(__STDC__) || defined(__cplusplus)
79 #define	__P(protos)	protos		/* full-blown ANSI C */
80 #define	__CONCAT1(x,y)	x ## y
81 #define	__CONCAT(x,y)	__CONCAT1(x,y)
82 #define	__STRING(x)	#x		/* stringify without expanding x */
83 #define	__XSTRING(x)	__STRING(x)	/* expand x, then stringify */
84 
85 #define	__const		const		/* define reserved names to standard */
86 #define	__signed	signed
87 #define	__volatile	volatile
88 #if defined(__cplusplus)
89 #define	__inline	inline		/* convert to C++ keyword */
90 #else
91 #ifndef __GNUC__
92 #define	__inline			/* delete GCC keyword */
93 #endif /* !__GNUC__ */
94 #endif /* !__cplusplus */
95 
96 #else	/* !(__STDC__ || __cplusplus) */
97 #define	__P(protos)	()		/* traditional C preprocessor */
98 #define	__CONCAT(x,y)	x/**/y
99 #define	__STRING(x)	"x"
100 
101 #ifndef __GNUC__
102 #define	__const				/* delete pseudo-ANSI C keywords */
103 #define	__inline
104 #define	__signed
105 #define	__volatile
106 /*
107  * In non-ANSI C environments, new programs will want ANSI-only C keywords
108  * deleted from the program and old programs will want them left alone.
109  * When using a compiler other than gcc, programs using the ANSI C keywords
110  * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
111  * When using "gcc -traditional", we assume that this is the intent; if
112  * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
113  */
114 #ifndef	NO_ANSI_KEYWORDS
115 #define	const				/* delete ANSI C keywords */
116 #define	inline
117 #define	signed
118 #define	volatile
119 #endif	/* !NO_ANSI_KEYWORDS */
120 #endif	/* !__GNUC__ */
121 #endif	/* !(__STDC__ || __cplusplus) */
122 
123 /*
124  * Compiler-dependent macros to help declare dead (non-returning) and
125  * pure (no side effects) functions, and unused variables.  They are
126  * null except for versions of gcc that are known to support the features
127  * properly (old versions of gcc-2 supported the dead and pure features
128  * in a different (wrong) way).
129  */
130 #if __GNUC__ < 2 || __GNUC__ == 2 && __GNUC_MINOR__ < 5
131 #define __dead2
132 #define __pure2
133 #define __unused
134 #endif
135 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7
136 #define __dead2		__attribute__((__noreturn__))
137 #define __pure2		__attribute__((__const__))
138 #define __unused
139 #endif
140 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 7 || __GNUC__ == 3
141 #define __dead2		__attribute__((__noreturn__))
142 #define __pure2		__attribute__((__const__))
143 #define __unused	__attribute__((__unused__))
144 #endif
145 
146 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
147 #if !(__GNUC__ == 2 && __GNUC_MINOR__ >= 7 || __GNUC__ >= 3)
148 #define	__func__	NULL
149 #endif
150 
151 #if __GNUC__ >= 2 && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
152 #define	__LONG_LONG_SUPPORTED
153 #endif
154 
155 /*
156  * GCC 2.95 provides `__restrict' as an extention to C90 to support the
157  * C99-specific `restrict' type qualifier.  We happen to use `__restrict' as
158  * a way to define the `restrict' type qualifier without disturbing older
159  * software that is unaware of C99 keywords.
160  */
161 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
162 #if __STDC_VERSION__ < 199901
163 #define	__restrict
164 #else
165 #define	__restrict	restrict
166 #endif
167 #endif
168 
169 /*
170  * Compiler-dependent macros to declare that functions take printf-like
171  * or scanf-like arguments.  They are null except for versions of gcc
172  * that are known to support the features properly (old versions of gcc-2
173  * didn't permit keeping the keywords out of the application namespace).
174  */
175 #if __GNUC__ < 2 || __GNUC__ == 2 && __GNUC_MINOR__ < 7
176 #define	__printflike(fmtarg, firstvararg)
177 #define	__scanflike(fmtarg, firstvararg)
178 #else
179 #define	__printflike(fmtarg, firstvararg) \
180 	    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
181 #define	__scanflike(fmtarg, firstvararg) \
182 	    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
183 #endif
184 
185 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
186 #if __FreeBSD_cc_version >= 300001
187 #define	__printf0like(fmtarg, firstvararg) \
188 	    __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
189 #else
190 #define	__printf0like(fmtarg, firstvararg)
191 #endif
192 
193 /*
194  * Handy GCC based macros:
195  *
196  * 	__cachealign:
197  *
198  * 	The __cachealign macro can be used for cache line aligning structures
199  * 	of small to medium size.  It aligns the particular structure or
200  * 	storage type to a system default cache line alignment, thus giving us
201  * 	a much more better cache utilization by making the hardware work at
202  * 	its best burst speeds.
203  *
204  * 	__usereg:
205  *
206  * 	The __usereg macro can/should be used when a function contains
207  * 	arguments not more than 3.  It can be very useful to us due to the
208  * 	message-passing nature of the kernel.
209  *
210  * !!NOTE - USAGE INFORMATION!!
211  *
212  * The __cachealign macro should not be used for data structures that are
213  * as big struct proc, struct vnode, struct thread, and other structs which
214  * are as big as them; simply because it will be useless in that case.
215  *
216  * The __usereg macro should be used whenever possible, i.e., when a function
217  * does not exceed more than 3 arguments, and should not be used for vararg
218  * type functions.
219  *
220  * In other words, AVOID MISUSE OF THESE MACROS. :-)
221  */
222 #ifdef __GNUC__
223 #define	__cachealign	__attribute__((aligned(VM_CACHELINE_SIZE)))
224 #define	__usereg     	__attribute__((regparm(3)))
225 #else
226 #define	__cachealign
227 #define	__usereg
228 #endif
229 
230 #ifdef __GNUC__
231 #define __strong_reference(sym,aliassym)	\
232 	extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)));
233 #ifdef __ELF__
234 #ifdef __STDC__
235 #define	__weak_reference(sym,alias)	\
236 	__asm__(".weak " #alias);	\
237 	__asm__(".equ "  #alias ", " #sym)
238 #define	__warn_references(sym,msg)	\
239 	__asm__(".section .gnu.warning." #sym);	\
240 	__asm__(".asciz \"" msg "\"");	\
241 	__asm__(".previous")
242 #else
243 #define	__weak_reference(sym,alias)	\
244 	__asm__(".weak alias");		\
245 	__asm__(".equ alias, sym")
246 #define	__warn_references(sym,msg)	\
247 	__asm__(".section .gnu.warning.sym"); \
248 	__asm__(".asciz \"msg\"");	\
249 	__asm__(".previous")
250 #endif	/* __STDC__ */
251 #else	/* !__ELF__ */
252 #ifdef __STDC__
253 #define __weak_reference(sym,alias)	\
254 	__asm__(".stabs \"_" #alias "\",11,0,0,0");	\
255 	__asm__(".stabs \"_" #sym "\",1,0,0,0")
256 #define __warn_references(sym,msg)	\
257 	__asm__(".stabs \"" msg "\",30,0,0,0");		\
258 	__asm__(".stabs \"_" #sym "\",1,0,0,0")
259 #else
260 #define __weak_reference(sym,alias)	\
261 	__asm__(".stabs \"_/**/alias\",11,0,0,0");	\
262 	__asm__(".stabs \"_/**/sym\",1,0,0,0")
263 #define __warn_references(sym,msg)	\
264 	__asm__(".stabs msg,30,0,0,0");			\
265 	__asm__(".stabs \"_/**/sym\",1,0,0,0")
266 #endif	/* __STDC__ */
267 #endif	/* __ELF__ */
268 #endif	/* __GNUC__ */
269 
270 #if defined(__GNUC__) && defined(__ELF__)
271 #define	__IDSTRING(name,string)	__asm__(".ident\t\"" string "\"")
272 #else
273 #define	__IDSTRING(name,string)	static const char name[] __unused = string
274 #endif
275 
276 #ifndef	__RCSID
277 #define	__RCSID(s)	__IDSTRING(rcsid,s)
278 #endif
279 
280 #ifndef	__RCSID_SOURCE
281 #define	__RCSID_SOURCE(s) __IDSTRING(rcsid_source,s)
282 #endif
283 
284 #ifndef	__COPYRIGHT
285 #define	__COPYRIGHT(s)	__IDSTRING(copyright,s)
286 #endif
287 
288 /*-
289  * The following definitions are an extension of the behavior originally
290  * implemented in <sys/_posix.h>, but with a different level of granularity.
291  * POSIX.1 requires that the macros we test be defined before any standard
292  * header file is included.
293  *
294  * Here's a quick run-down of the versions:
295  *  defined(_POSIX_SOURCE)		1003.1-1988
296  *  _POSIX_C_SOURCE == 1		1003.1-1990
297  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
298  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
299  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
300  *					and the omnibus ISO/IEC 9945-1: 1996
301  *  _POSIX_C_SOURCE == 200112		1003.1-2001
302  *
303  * In addition, the X/Open Portability Guide, which is now the Single UNIX
304  * Specification, defines a feature-test macro which indicates the version of
305  * that specification, and which subsumes _POSIX_C_SOURCE.
306  *
307  * Our macros begin with two underscores to avoid namespace screwage.
308  */
309 
310 #if defined(_POSIX_C_SOURCE)
311 
312 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
313 #if _POSIX_C_SOURCE == 1
314 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
315 #define	_POSIX_C_SOURCE		199009
316 #endif
317 
318 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
319 #if _POSIX_C_SOURCE == 2
320 #undef _POSIX_C_SOURCE
321 #define	_POSIX_C_SOURCE		199209
322 #endif
323 
324 #endif	/* _POSIX_C_SOURCE */
325 
326 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
327 #ifdef _XOPEN_SOURCE
328 #if _XOPEN_SOURCE - 0 >= 600
329 #define	__XSI_VISIBLE		600
330 #undef _POSIX_C_SOURCE
331 #define	_POSIX_C_SOURCE		200112
332 #elif _XOPEN_SOURCE - 0 >= 500
333 #define	__XSI_VISIBLE		500
334 #undef _POSIX_C_SOURCE
335 #define	_POSIX_C_SOURCE		199506
336 #endif
337 #endif
338 
339 /*
340  * Deal with all versions of POSIX.  The ordering relative to the tests above is
341  * important.
342  */
343 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
344 #define	_POSIX_C_SOURCE		198808
345 #endif
346 #ifdef _POSIX_C_SOURCE
347 #if _POSIX_C_SOURCE >= 200112
348 #define	__POSIX_VISIBLE		200112
349 #define	__ISO_C_VISIBLE		1999
350 #elif _POSIX_C_SOURCE >= 199506
351 #define	__POSIX_VISIBLE		199506
352 #define	__ISO_C_VISIBLE		1990
353 #elif _POSIX_C_SOURCE >= 199309
354 #define	__POSIX_VISIBLE		199309
355 #define	__ISO_C_VISIBLE		1990
356 #elif _POSIX_C_SOURCE >= 199209
357 #define	__POSIX_VISIBLE		199209
358 #define	__ISO_C_VISIBLE		1990
359 #elif _POSIX_C_SOURCE >= 199009
360 #define	__POSIX_VISIBLE		199009
361 #define	__ISO_C_VISIBLE		1990
362 #else
363 #define	__POSIX_VISIBLE		198808
364 #define	__ISO_C_VISIBLE		0
365 #endif /* _POSIX_C_SOURCE */
366 #else
367 /*-
368  * Deal with _ANSI_SOURCE:
369  * If it is defined, and no other compilation environment is explicitly
370  * requested, then define our internal feature-test macros to zero.  This
371  * makes no difference to the preprocessor (undefined symbols in preprocessing
372  * expressions are defined to have value zero), but makes it more convenient for
373  * a test program to print out the values.
374  *
375  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
376  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
377  * environment (and in fact we will never get here).
378  */
379 #ifdef _ANSI_SOURCE		/* Hide almost everything. */
380 #define	__POSIX_VISIBLE		0
381 #define	__XSI_VISIBLE		0
382 #define	__BSD_VISIBLE		0
383 #define	__ISO_C_VISIBLE		1990
384 #else				/* Default environment: show everything. */
385 #define	__POSIX_VISIBLE		200112
386 #define	__XSI_VISIBLE		600
387 #define	__BSD_VISIBLE		1
388 #define	__ISO_C_VISIBLE		1999
389 #endif
390 #endif
391 
392 #endif /* !_SYS_CDEFS_H_ */
393