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      1 /*	$NetBSD: cdefs.h,v 1.58 2004/12/11 05:59:00 christos Exp $	*/
      2 
      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  */
     36 
     37 #ifndef	_SYS_CDEFS_H_
     38 #define	_SYS_CDEFS_H_
     39 
     40 /*
     41  * Macro to test if we're using a GNU C compiler of a specific vintage
     42  * or later, for e.g. features that appeared in a particular version
     43  * of GNU C.  Usage:
     44  *
     45  *	#if __GNUC_PREREQ__(major, minor)
     46  *	...cool feature...
     47  *	#else
     48  *	...delete feature...
     49  *	#endif
     50  */
     51 #ifdef __GNUC__
     52 #define	__GNUC_PREREQ__(x, y)						\
     53 	((__GNUC__ == (x) && __GNUC_MINOR__ >= (y)) ||			\
     54 	 (__GNUC__ > (x)))
     55 #else
     56 #define	__GNUC_PREREQ__(x, y)	0
     57 #endif
     58 
     59 #include <sys/cdefs_elf.h>
     60 
     61 #if defined(__cplusplus)
     62 #define	__BEGIN_DECLS		extern "C" {
     63 #define	__END_DECLS		}
     64 #define	__static_cast(x,y)	static_cast<x>(y)
     65 #else
     66 #define	__BEGIN_DECLS
     67 #define	__END_DECLS
     68 #define	__static_cast(x,y)	(x)y
     69 #endif
     70 
     71 /*
     72  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
     73  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
     74  * The __CONCAT macro is a bit tricky -- make sure you don't put spaces
     75  * in between its arguments.  __CONCAT can also concatenate double-quoted
     76  * strings produced by the __STRING macro, but this only works with ANSI C.
     77  */
     78 
     79 #define	___STRING(x)	__STRING(x)
     80 #define	___CONCAT(x,y)	__CONCAT(x,y)
     81 
     82 #if __STDC__ || defined(__cplusplus)
     83 #define	__P(protos)	protos		/* full-blown ANSI C */
     84 #define	__CONCAT(x,y)	x ## y
     85 #define	__STRING(x)	#x
     86 
     87 #define	__const		const		/* define reserved names to standard */
     88 #define	__signed	signed
     89 #define	__volatile	volatile
     90 #if defined(__cplusplus)
     91 #define	__inline	inline		/* convert to C++ keyword */
     92 #else
     93 #if !defined(__GNUC__) && !defined(__lint__)
     94 #define	__inline			/* delete GCC keyword */
     95 #endif /* !__GNUC__  && !__lint__ */
     96 #endif /* !__cplusplus */
     97 
     98 #else	/* !(__STDC__ || __cplusplus) */
     99 #define	__P(protos)	()		/* traditional C preprocessor */
    100 #define	__CONCAT(x,y)	x/**/y
    101 #define	__STRING(x)	"x"
    102 
    103 #ifndef __GNUC__
    104 #define	__const				/* delete pseudo-ANSI C keywords */
    105 #define	__inline
    106 #define	__signed
    107 #define	__volatile
    108 #endif	/* !__GNUC__ */
    109 
    110 /*
    111  * In non-ANSI C environments, new programs will want ANSI-only C keywords
    112  * deleted from the program and old programs will want them left alone.
    113  * Programs using the ANSI C keywords const, inline etc. as normal
    114  * identifiers should define -DNO_ANSI_KEYWORDS.
    115  */
    116 #ifndef	NO_ANSI_KEYWORDS
    117 #define	const		__const		/* convert ANSI C keywords */
    118 #define	inline		__inline
    119 #define	signed		__signed
    120 #define	volatile	__volatile
    121 #endif /* !NO_ANSI_KEYWORDS */
    122 #endif	/* !(__STDC__ || __cplusplus) */
    123 
    124 /*
    125  * Used for internal auditing of the NetBSD source tree.
    126  */
    127 #ifdef __AUDIT__
    128 #define	__aconst	__const
    129 #else
    130 #define	__aconst
    131 #endif
    132 
    133 /*
    134  * The following macro is used to remove const cast-away warnings
    135  * from gcc -Wcast-qual; it should be used with caution because it
    136  * can hide valid errors; in particular most valid uses are in
    137  * situations where the API requires it, not to cast away string
    138  * constants. We don't use *intptr_t on purpose here and we are
    139  * explicit about unsigned long so that we don't have additional
    140  * dependencies.
    141  */
    142 #define __UNCONST(a)	((void *)(unsigned long)(const void *)(a))
    143 
    144 /*
    145  * GCC2 provides __extension__ to suppress warnings for various GNU C
    146  * language extensions under "-ansi -pedantic".
    147  */
    148 #if !__GNUC_PREREQ__(2, 0)
    149 #define	__extension__		/* delete __extension__ if non-gcc or gcc1 */
    150 #endif
    151 
    152 /*
    153  * GCC1 and some versions of GCC2 declare dead (non-returning) and
    154  * pure (no side effects) functions using "volatile" and "const";
    155  * unfortunately, these then cause warnings under "-ansi -pedantic".
    156  * GCC2 uses a new, peculiar __attribute__((attrs)) style.  All of
    157  * these work for GNU C++ (modulo a slight glitch in the C++ grammar
    158  * in the distribution version of 2.5.5).
    159  */
    160 #if !__GNUC_PREREQ__(2, 5)
    161 #define	__attribute__(x)	/* delete __attribute__ if non-gcc or gcc1 */
    162 #if defined(__GNUC__) && !defined(__STRICT_ANSI__)
    163 #define	__dead		__volatile
    164 #define	__pure		__const
    165 #endif
    166 #endif
    167 
    168 /* Delete pseudo-keywords wherever they are not available or needed. */
    169 #ifndef __dead
    170 #define	__dead
    171 #define	__pure
    172 #endif
    173 
    174 #if __GNUC_PREREQ__(2, 7)
    175 #define	__unused	__attribute__((__unused__))
    176 #else
    177 #define	__unused	/* delete */
    178 #endif
    179 
    180 #if __GNUC_PREREQ__(3, 1)
    181 #define	__used		__attribute__((__used__))
    182 #else
    183 #define	__used		/* delete */
    184 #endif
    185 
    186 #if __GNUC_PREREQ__(2, 7)
    187 #define	__packed	__attribute__((__packed__))
    188 #define	__aligned(x)	__attribute__((__aligned__(x)))
    189 #define	__section(x)	__attribute__((__section__(x)))
    190 #elif defined(__lint__)
    191 #define	__packed	/* delete */
    192 #define	__aligned(x)	/* delete */
    193 #define	__section(x)	/* delete */
    194 #else
    195 #define	__packed	error: no __packed for this compiler
    196 #define	__aligned(x)	error: no __aligned for this compiler
    197 #define	__section(x)	error: no __section for this compiler
    198 #endif
    199 
    200 #if !__GNUC_PREREQ__(2, 8)
    201 #define	__extension__
    202 #endif
    203 
    204 #if __GNUC_PREREQ__(2, 8)
    205 #define __statement(x)	__extension__(x)
    206 #elif defined(lint)
    207 #define __statement(x)	(0)
    208 #else
    209 #define __statement(x)	(x)
    210 #endif
    211 
    212 /*
    213  * C99 defines the restrict type qualifier keyword, which was made available
    214  * in GCC 2.92.
    215  */
    216 #if __STDC_VERSION__ >= 199901L
    217 #define	__restrict	restrict
    218 #else
    219 #if !__GNUC_PREREQ__(2, 92)
    220 #define	__restrict	/* delete __restrict when not supported */
    221 #endif
    222 #endif
    223 
    224 /*
    225  * C99 defines __func__ predefined identifier, which was made available
    226  * in GCC 2.95.
    227  */
    228 #if !(__STDC_VERSION__ >= 199901L)
    229 #if __GNUC_PREREQ__(2, 6)
    230 #define	__func__	__PRETTY_FUNCTION__
    231 #elif __GNUC_PREREQ__(2, 4)
    232 #define	__func__	__FUNCTION__
    233 #else
    234 #define	__func__	""
    235 #endif
    236 #endif /* !(__STDC_VERSION__ >= 199901L) */
    237 
    238 #if defined(_KERNEL)
    239 #if defined(NO_KERNEL_RCSIDS)
    240 #undef __KERNEL_RCSID
    241 #define	__KERNEL_RCSID(_n, _s)		/* nothing */
    242 #endif /* NO_KERNEL_RCSIDS */
    243 #endif /* _KERNEL */
    244 
    245 #if !defined(_STANDALONE) && !defined(_KERNEL)
    246 #ifdef __GNUC__
    247 #define	__RENAME(x)	___RENAME(x)
    248 #else
    249 #ifdef __lint__
    250 #define	__RENAME(x)	__symbolrename(x)
    251 #else
    252 #error "No function renaming possible"
    253 #endif /* __lint__ */
    254 #endif /* __GNUC__ */
    255 #else /* _STANDALONE || _KERNEL */
    256 #define	__RENAME(x)	no renaming in kernel or standalone environment
    257 #endif
    258 
    259 /*
    260  * A barrier to stop the optimizer from moving code or assume live
    261  * register values. This is gcc specific, the version is more or less
    262  * arbitrary, might work with older compilers.
    263  */
    264 #if __GNUC_PREREQ__(2, 95)
    265 #define	__insn_barrier()	__asm __volatile("":::"memory")
    266 #else
    267 #define	__insn_barrier()	/* */
    268 #endif
    269 
    270 /*
    271  * GNU C version 2.96 adds explicit branch prediction so that
    272  * the CPU back-end can hint the processor and also so that
    273  * code blocks can be reordered such that the predicted path
    274  * sees a more linear flow, thus improving cache behavior, etc.
    275  *
    276  * The following two macros provide us with a way to use this
    277  * compiler feature.  Use __predict_true() if you expect the expression
    278  * to evaluate to true, and __predict_false() if you expect the
    279  * expression to evaluate to false.
    280  *
    281  * A few notes about usage:
    282  *
    283  *	* Generally, __predict_false() error condition checks (unless
    284  *	  you have some _strong_ reason to do otherwise, in which case
    285  *	  document it), and/or __predict_true() `no-error' condition
    286  *	  checks, assuming you want to optimize for the no-error case.
    287  *
    288  *	* Other than that, if you don't know the likelihood of a test
    289  *	  succeeding from empirical or other `hard' evidence, don't
    290  *	  make predictions.
    291  *
    292  *	* These are meant to be used in places that are run `a lot'.
    293  *	  It is wasteful to make predictions in code that is run
    294  *	  seldomly (e.g. at subsystem initialization time) as the
    295  *	  basic block reordering that this affects can often generate
    296  *	  larger code.
    297  */
    298 #if __GNUC_PREREQ__(2, 96)
    299 #define	__predict_true(exp)	__builtin_expect((exp) != 0, 1)
    300 #define	__predict_false(exp)	__builtin_expect((exp) != 0, 0)
    301 #else
    302 #define	__predict_true(exp)	(exp)
    303 #define	__predict_false(exp)	(exp)
    304 #endif
    305 
    306 #if __GNUC_PREREQ__(2, 96)
    307 #define __noreturn    __attribute__((__noreturn__))
    308 #define __mallocfunc  __attribute__((malloc))
    309 #else
    310 #define __noreturn
    311 #define __mallocfunc
    312 #endif
    313 
    314 /*
    315  * Macros for manipulating "link sets".  Link sets are arrays of pointers
    316  * to objects, which are gathered up by the linker.
    317  *
    318  * Object format-specific code has provided us with the following macros:
    319  *
    320  *	__link_set_add_text(set, sym)
    321  *		Add a reference to the .text symbol `sym' to `set'.
    322  *
    323  *	__link_set_add_rodata(set, sym)
    324  *		Add a reference to the .rodata symbol `sym' to `set'.
    325  *
    326  *	__link_set_add_data(set, sym)
    327  *		Add a reference to the .data symbol `sym' to `set'.
    328  *
    329  *	__link_set_add_bss(set, sym)
    330  *		Add a reference to the .bss symbol `sym' to `set'.
    331  *
    332  *	__link_set_decl(set, ptype)
    333  *		Provide an extern declaration of the set `set', which
    334  *		contains an array of the pointer type `ptype'.  This
    335  *		macro must be used by any code which wishes to reference
    336  *		the elements of a link set.
    337  *
    338  *	__link_set_start(set)
    339  *		This points to the first slot in the link set.
    340  *
    341  *	__link_set_end(set)
    342  *		This points to the (non-existent) slot after the last
    343  *		entry in the link set.
    344  *
    345  *	__link_set_count(set)
    346  *		Count the number of entries in link set `set'.
    347  *
    348  * In addition, we provide the following macros for accessing link sets:
    349  *
    350  *	__link_set_foreach(pvar, set)
    351  *		Iterate over the link set `set'.  Because a link set is
    352  *		an array of pointers, pvar must be declared as "type **pvar",
    353  *		and the actual entry accessed as "*pvar".
    354  *
    355  *	__link_set_entry(set, idx)
    356  *		Access the link set entry at index `idx' from set `set'.
    357  */
    358 #define	__link_set_foreach(pvar, set)					\
    359 	for (pvar = __link_set_start(set); pvar < __link_set_end(set); pvar++)
    360 
    361 #define	__link_set_entry(set, idx)	(__link_set_begin(set)[idx])
    362 
    363 /*
    364  * Some of the recend FreeBSD sources used in Bionic need this.
    365  * Originally, this is used to embed the rcs versions of each source file
    366  * in the generated binary. We certainly don't want this in Bionic.
    367  */
    368 #define	__FBSDID(s)	struct __hack
    369 
    370 /*-
    371  * The following definitions are an extension of the behavior originally
    372  * implemented in <sys/_posix.h>, but with a different level of granularity.
    373  * POSIX.1 requires that the macros we test be defined before any standard
    374  * header file is included.
    375  *
    376  * Here's a quick run-down of the versions:
    377  *  defined(_POSIX_SOURCE)		1003.1-1988
    378  *  _POSIX_C_SOURCE == 1		1003.1-1990
    379  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
    380  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
    381  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
    382  *					and the omnibus ISO/IEC 9945-1: 1996
    383  *  _POSIX_C_SOURCE == 200112		1003.1-2001
    384  *  _POSIX_C_SOURCE == 200809		1003.1-2008
    385  *
    386  * In addition, the X/Open Portability Guide, which is now the Single UNIX
    387  * Specification, defines a feature-test macro which indicates the version of
    388  * that specification, and which subsumes _POSIX_C_SOURCE.
    389  *
    390  * Our macros begin with two underscores to avoid namespace screwage.
    391  */
    392 
    393 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
    394 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
    395 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
    396 #define	_POSIX_C_SOURCE		199009
    397 #endif
    398 
    399 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
    400 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
    401 #undef _POSIX_C_SOURCE
    402 #define	_POSIX_C_SOURCE		199209
    403 #endif
    404 
    405 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
    406 #ifdef _XOPEN_SOURCE
    407 #if _XOPEN_SOURCE - 0 >= 700
    408 #define	__XSI_VISIBLE		700
    409 #undef _POSIX_C_SOURCE
    410 #define	_POSIX_C_SOURCE		200809
    411 #elif _XOPEN_SOURCE - 0 >= 600
    412 #define	__XSI_VISIBLE		600
    413 #undef _POSIX_C_SOURCE
    414 #define	_POSIX_C_SOURCE		200112
    415 #elif _XOPEN_SOURCE - 0 >= 500
    416 #define	__XSI_VISIBLE		500
    417 #undef _POSIX_C_SOURCE
    418 #define	_POSIX_C_SOURCE		199506
    419 #endif
    420 #endif
    421 
    422 /*
    423  * Deal with all versions of POSIX.  The ordering relative to the tests above is
    424  * important.
    425  */
    426 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
    427 #define	_POSIX_C_SOURCE		198808
    428 #endif
    429 #ifdef _POSIX_C_SOURCE
    430 #if _POSIX_C_SOURCE >= 200809
    431 #define	__POSIX_VISIBLE		200809
    432 #define	__ISO_C_VISIBLE		1999
    433 #elif _POSIX_C_SOURCE >= 200112
    434 #define	__POSIX_VISIBLE		200112
    435 #define	__ISO_C_VISIBLE		1999
    436 #elif _POSIX_C_SOURCE >= 199506
    437 #define	__POSIX_VISIBLE		199506
    438 #define	__ISO_C_VISIBLE		1990
    439 #elif _POSIX_C_SOURCE >= 199309
    440 #define	__POSIX_VISIBLE		199309
    441 #define	__ISO_C_VISIBLE		1990
    442 #elif _POSIX_C_SOURCE >= 199209
    443 #define	__POSIX_VISIBLE		199209
    444 #define	__ISO_C_VISIBLE		1990
    445 #elif _POSIX_C_SOURCE >= 199009
    446 #define	__POSIX_VISIBLE		199009
    447 #define	__ISO_C_VISIBLE		1990
    448 #else
    449 #define	__POSIX_VISIBLE		198808
    450 #define	__ISO_C_VISIBLE		0
    451 #endif /* _POSIX_C_SOURCE */
    452 #else
    453 /*-
    454  * Deal with _ANSI_SOURCE:
    455  * If it is defined, and no other compilation environment is explicitly
    456  * requested, then define our internal feature-test macros to zero.  This
    457  * makes no difference to the preprocessor (undefined symbols in preprocessing
    458  * expressions are defined to have value zero), but makes it more convenient for
    459  * a test program to print out the values.
    460  *
    461  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
    462  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
    463  * environment (and in fact we will never get here).
    464  */
    465 #if defined(_ANSI_SOURCE)	/* Hide almost everything. */
    466 #define	__POSIX_VISIBLE		0
    467 #define	__XSI_VISIBLE		0
    468 #define	__BSD_VISIBLE		0
    469 #define	__ISO_C_VISIBLE		1990
    470 #elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
    471 #define	__POSIX_VISIBLE		0
    472 #define	__XSI_VISIBLE		0
    473 #define	__BSD_VISIBLE		0
    474 #define	__ISO_C_VISIBLE		1999
    475 #else				/* Default environment: show everything. */
    476 #define	__POSIX_VISIBLE		200809
    477 #define	__XSI_VISIBLE		700
    478 #define	__BSD_VISIBLE		1
    479 #define	__ISO_C_VISIBLE		1999
    480 #endif
    481 #endif
    482 
    483 /*
    484  * Default values.
    485  */
    486 #ifndef __XPG_VISIBLE
    487 # define __XPG_VISIBLE          700
    488 #endif
    489 #ifndef __POSIX_VISIBLE
    490 # define __POSIX_VISIBLE        200809
    491 #endif
    492 #ifndef __ISO_C_VISIBLE
    493 # define __ISO_C_VISIBLE        1999
    494 #endif
    495 #ifndef __BSD_VISIBLE
    496 # define __BSD_VISIBLE          1
    497 #endif
    498 
    499 #define  __BIONIC__   1
    500 
    501 #endif /* !_SYS_CDEFS_H_ */
    502