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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 defined(__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 #define __pure2 __attribute__((__const__)) /* Android-added: used by FreeBSD libm */
    181 
    182 #if __GNUC_PREREQ__(3, 1)
    183 #define	__used		__attribute__((__used__))
    184 #else
    185 #define	__used		/* delete */
    186 #endif
    187 
    188 #if __GNUC_PREREQ__(2, 7)
    189 #define	__packed	__attribute__((__packed__))
    190 #define	__aligned(x)	__attribute__((__aligned__(x)))
    191 #define	__section(x)	__attribute__((__section__(x)))
    192 #elif defined(__lint__)
    193 #define	__packed	/* delete */
    194 #define	__aligned(x)	/* delete */
    195 #define	__section(x)	/* delete */
    196 #else
    197 #define	__packed	error: no __packed for this compiler
    198 #define	__aligned(x)	error: no __aligned for this compiler
    199 #define	__section(x)	error: no __section for this compiler
    200 #endif
    201 
    202 #if !__GNUC_PREREQ__(2, 8)
    203 #define	__extension__
    204 #endif
    205 
    206 #if __GNUC_PREREQ__(2, 8)
    207 #define __statement(x)	__extension__(x)
    208 #elif defined(lint)
    209 #define __statement(x)	(0)
    210 #else
    211 #define __statement(x)	(x)
    212 #endif
    213 
    214 /*
    215  * C99 defines the restrict type qualifier keyword, which was made available
    216  * in GCC 2.92.
    217  */
    218 #if defined(__STDC__VERSION__) && __STDC_VERSION__ >= 199901L
    219 #define	__restrict	restrict
    220 #else
    221 #if !__GNUC_PREREQ__(2, 92)
    222 #define	__restrict	/* delete __restrict when not supported */
    223 #endif
    224 #endif
    225 
    226 /*
    227  * C99 defines __func__ predefined identifier, which was made available
    228  * in GCC 2.95.
    229  */
    230 #if !defined(__STDC_VERSION__) || !(__STDC_VERSION__ >= 199901L)
    231 #if __GNUC_PREREQ__(2, 6)
    232 #define	__func__	__PRETTY_FUNCTION__
    233 #elif __GNUC_PREREQ__(2, 4)
    234 #define	__func__	__FUNCTION__
    235 #else
    236 #define	__func__	""
    237 #endif
    238 #endif /* !(__STDC_VERSION__ >= 199901L) */
    239 
    240 #if defined(_KERNEL)
    241 #if defined(NO_KERNEL_RCSIDS)
    242 #undef __KERNEL_RCSID
    243 #define	__KERNEL_RCSID(_n, _s)		/* nothing */
    244 #endif /* NO_KERNEL_RCSIDS */
    245 #endif /* _KERNEL */
    246 
    247 #if !defined(_STANDALONE) && !defined(_KERNEL)
    248 #ifdef __GNUC__
    249 #define	__RENAME(x)	___RENAME(x)
    250 #else
    251 #ifdef __lint__
    252 #define	__RENAME(x)	__symbolrename(x)
    253 #else
    254 #error "No function renaming possible"
    255 #endif /* __lint__ */
    256 #endif /* __GNUC__ */
    257 #else /* _STANDALONE || _KERNEL */
    258 #define	__RENAME(x)	no renaming in kernel or standalone environment
    259 #endif
    260 
    261 /*
    262  * A barrier to stop the optimizer from moving code or assume live
    263  * register values. This is gcc specific, the version is more or less
    264  * arbitrary, might work with older compilers.
    265  */
    266 #if __GNUC_PREREQ__(2, 95)
    267 #define	__insn_barrier()	__asm __volatile("":::"memory")
    268 #else
    269 #define	__insn_barrier()	/* */
    270 #endif
    271 
    272 /*
    273  * GNU C version 2.96 adds explicit branch prediction so that
    274  * the CPU back-end can hint the processor and also so that
    275  * code blocks can be reordered such that the predicted path
    276  * sees a more linear flow, thus improving cache behavior, etc.
    277  *
    278  * The following two macros provide us with a way to use this
    279  * compiler feature.  Use __predict_true() if you expect the expression
    280  * to evaluate to true, and __predict_false() if you expect the
    281  * expression to evaluate to false.
    282  *
    283  * A few notes about usage:
    284  *
    285  *	* Generally, __predict_false() error condition checks (unless
    286  *	  you have some _strong_ reason to do otherwise, in which case
    287  *	  document it), and/or __predict_true() `no-error' condition
    288  *	  checks, assuming you want to optimize for the no-error case.
    289  *
    290  *	* Other than that, if you don't know the likelihood of a test
    291  *	  succeeding from empirical or other `hard' evidence, don't
    292  *	  make predictions.
    293  *
    294  *	* These are meant to be used in places that are run `a lot'.
    295  *	  It is wasteful to make predictions in code that is run
    296  *	  seldomly (e.g. at subsystem initialization time) as the
    297  *	  basic block reordering that this affects can often generate
    298  *	  larger code.
    299  */
    300 #if __GNUC_PREREQ__(2, 96)
    301 #define	__predict_true(exp)	__builtin_expect((exp) != 0, 1)
    302 #define	__predict_false(exp)	__builtin_expect((exp) != 0, 0)
    303 #else
    304 #define	__predict_true(exp)	(exp)
    305 #define	__predict_false(exp)	(exp)
    306 #endif
    307 
    308 #if __GNUC_PREREQ__(2, 96)
    309 #define __noreturn    __attribute__((__noreturn__))
    310 #define __mallocfunc  __attribute__((malloc))
    311 #define __purefunc    __attribute__((pure))
    312 #else
    313 #define __noreturn
    314 #define __mallocfunc
    315 #define __purefunc
    316 #endif
    317 
    318 #if __GNUC_PREREQ__(3, 1)
    319 #define __always_inline __attribute__((__always_inline__))
    320 #else
    321 #define __always_inline
    322 #endif
    323 
    324 #if __GNUC_PREREQ__(3, 4)
    325 #define __wur __attribute__((__warn_unused_result__))
    326 #else
    327 #define __wur
    328 #endif
    329 
    330 /*
    331  * Macros for manipulating "link sets".  Link sets are arrays of pointers
    332  * to objects, which are gathered up by the linker.
    333  *
    334  * Object format-specific code has provided us with the following macros:
    335  *
    336  *	__link_set_add_text(set, sym)
    337  *		Add a reference to the .text symbol `sym' to `set'.
    338  *
    339  *	__link_set_add_rodata(set, sym)
    340  *		Add a reference to the .rodata symbol `sym' to `set'.
    341  *
    342  *	__link_set_add_data(set, sym)
    343  *		Add a reference to the .data symbol `sym' to `set'.
    344  *
    345  *	__link_set_add_bss(set, sym)
    346  *		Add a reference to the .bss symbol `sym' to `set'.
    347  *
    348  *	__link_set_decl(set, ptype)
    349  *		Provide an extern declaration of the set `set', which
    350  *		contains an array of the pointer type `ptype'.  This
    351  *		macro must be used by any code which wishes to reference
    352  *		the elements of a link set.
    353  *
    354  *	__link_set_start(set)
    355  *		This points to the first slot in the link set.
    356  *
    357  *	__link_set_end(set)
    358  *		This points to the (non-existent) slot after the last
    359  *		entry in the link set.
    360  *
    361  *	__link_set_count(set)
    362  *		Count the number of entries in link set `set'.
    363  *
    364  * In addition, we provide the following macros for accessing link sets:
    365  *
    366  *	__link_set_foreach(pvar, set)
    367  *		Iterate over the link set `set'.  Because a link set is
    368  *		an array of pointers, pvar must be declared as "type **pvar",
    369  *		and the actual entry accessed as "*pvar".
    370  *
    371  *	__link_set_entry(set, idx)
    372  *		Access the link set entry at index `idx' from set `set'.
    373  */
    374 #define	__link_set_foreach(pvar, set)					\
    375 	for (pvar = __link_set_start(set); pvar < __link_set_end(set); pvar++)
    376 
    377 #define	__link_set_entry(set, idx)	(__link_set_begin(set)[idx])
    378 
    379 /*
    380  * Some of the FreeBSD sources used in Bionic need this.
    381  * Originally, this is used to embed the rcs versions of each source file
    382  * in the generated binary. We certainly don't want this in Bionic.
    383  */
    384 #define __FBSDID(s) /* nothing */
    385 
    386 /*-
    387  * The following definitions are an extension of the behavior originally
    388  * implemented in <sys/_posix.h>, but with a different level of granularity.
    389  * POSIX.1 requires that the macros we test be defined before any standard
    390  * header file is included.
    391  *
    392  * Here's a quick run-down of the versions:
    393  *  defined(_POSIX_SOURCE)		1003.1-1988
    394  *  _POSIX_C_SOURCE == 1		1003.1-1990
    395  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
    396  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
    397  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
    398  *					and the omnibus ISO/IEC 9945-1: 1996
    399  *  _POSIX_C_SOURCE == 200112		1003.1-2001
    400  *  _POSIX_C_SOURCE == 200809		1003.1-2008
    401  *
    402  * In addition, the X/Open Portability Guide, which is now the Single UNIX
    403  * Specification, defines a feature-test macro which indicates the version of
    404  * that specification, and which subsumes _POSIX_C_SOURCE.
    405  *
    406  * Our macros begin with two underscores to avoid namespace screwage.
    407  */
    408 
    409 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
    410 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
    411 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
    412 #define	_POSIX_C_SOURCE		199009
    413 #endif
    414 
    415 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
    416 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
    417 #undef _POSIX_C_SOURCE
    418 #define	_POSIX_C_SOURCE		199209
    419 #endif
    420 
    421 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
    422 #ifdef _XOPEN_SOURCE
    423 #if _XOPEN_SOURCE - 0 >= 700
    424 #define	__XSI_VISIBLE		700
    425 #undef _POSIX_C_SOURCE
    426 #define	_POSIX_C_SOURCE		200809
    427 #elif _XOPEN_SOURCE - 0 >= 600
    428 #define	__XSI_VISIBLE		600
    429 #undef _POSIX_C_SOURCE
    430 #define	_POSIX_C_SOURCE		200112
    431 #elif _XOPEN_SOURCE - 0 >= 500
    432 #define	__XSI_VISIBLE		500
    433 #undef _POSIX_C_SOURCE
    434 #define	_POSIX_C_SOURCE		199506
    435 #endif
    436 #endif
    437 
    438 /*
    439  * Deal with all versions of POSIX.  The ordering relative to the tests above is
    440  * important.
    441  */
    442 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
    443 #define	_POSIX_C_SOURCE		198808
    444 #endif
    445 #ifdef _POSIX_C_SOURCE
    446 #if _POSIX_C_SOURCE >= 200809
    447 #define	__POSIX_VISIBLE		200809
    448 #define	__ISO_C_VISIBLE		1999
    449 #elif _POSIX_C_SOURCE >= 200112
    450 #define	__POSIX_VISIBLE		200112
    451 #define	__ISO_C_VISIBLE		1999
    452 #elif _POSIX_C_SOURCE >= 199506
    453 #define	__POSIX_VISIBLE		199506
    454 #define	__ISO_C_VISIBLE		1990
    455 #elif _POSIX_C_SOURCE >= 199309
    456 #define	__POSIX_VISIBLE		199309
    457 #define	__ISO_C_VISIBLE		1990
    458 #elif _POSIX_C_SOURCE >= 199209
    459 #define	__POSIX_VISIBLE		199209
    460 #define	__ISO_C_VISIBLE		1990
    461 #elif _POSIX_C_SOURCE >= 199009
    462 #define	__POSIX_VISIBLE		199009
    463 #define	__ISO_C_VISIBLE		1990
    464 #else
    465 #define	__POSIX_VISIBLE		198808
    466 #define	__ISO_C_VISIBLE		0
    467 #endif /* _POSIX_C_SOURCE */
    468 #else
    469 /*-
    470  * Deal with _ANSI_SOURCE:
    471  * If it is defined, and no other compilation environment is explicitly
    472  * requested, then define our internal feature-test macros to zero.  This
    473  * makes no difference to the preprocessor (undefined symbols in preprocessing
    474  * expressions are defined to have value zero), but makes it more convenient for
    475  * a test program to print out the values.
    476  *
    477  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
    478  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
    479  * environment (and in fact we will never get here).
    480  */
    481 #if defined(_ANSI_SOURCE)	/* Hide almost everything. */
    482 #define	__POSIX_VISIBLE		0
    483 #define	__XSI_VISIBLE		0
    484 #define	__BSD_VISIBLE		0
    485 #define	__ISO_C_VISIBLE		1990
    486 #elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
    487 #define	__POSIX_VISIBLE		0
    488 #define	__XSI_VISIBLE		0
    489 #define	__BSD_VISIBLE		0
    490 #define	__ISO_C_VISIBLE		1999
    491 #else				/* Default environment: show everything. */
    492 #define	__POSIX_VISIBLE		200809
    493 #define	__XSI_VISIBLE		700
    494 #define	__BSD_VISIBLE		1
    495 #define	__ISO_C_VISIBLE		1999
    496 #endif
    497 #endif
    498 
    499 /*
    500  * Default values.
    501  */
    502 #ifndef __XPG_VISIBLE
    503 # define __XPG_VISIBLE          700
    504 #endif
    505 #ifndef __POSIX_VISIBLE
    506 # define __POSIX_VISIBLE        200809
    507 #endif
    508 #ifndef __ISO_C_VISIBLE
    509 # define __ISO_C_VISIBLE        1999
    510 #endif
    511 #ifndef __BSD_VISIBLE
    512 # define __BSD_VISIBLE          1
    513 #endif
    514 
    515 #define  __BIONIC__   1
    516 #include <android/api-level.h>
    517 
    518 #if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && defined(__OPTIMIZE__) && __OPTIMIZE__ > 0 && !defined(__clang__)
    519 #define __BIONIC_FORTIFY 1
    520 #define __BIONIC_FORTIFY_INLINE \
    521     extern inline \
    522     __attribute__ ((always_inline)) \
    523     __attribute__ ((gnu_inline)) \
    524     __attribute__ ((artificial))
    525 #endif
    526 #define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1)
    527 
    528 /* Android-added: for FreeBSD's libm. */
    529 #define __weak_reference(sym,alias) \
    530     __asm__(".weak " #alias); \
    531     __asm__(".equ "  #alias ", " #sym)
    532 #define __strong_reference(sym,aliassym) \
    533     extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
    534 
    535 #endif /* !_SYS_CDEFS_H_ */
    536