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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  * Testing against Clang-specific extensions.
     42  */
     43 
     44 #ifndef __has_extension
     45 #define __has_extension         __has_feature
     46 #endif
     47 #ifndef __has_feature
     48 #define __has_feature(x)        0
     49 #endif
     50 #ifndef __has_include
     51 #define __has_include(x)        0
     52 #endif
     53 #ifndef __has_builtin
     54 #define __has_builtin(x)        0
     55 #endif
     56 #ifndef __has_attribute
     57 #define __has_attribute(x)      0
     58 #endif
     59 
     60 
     61 /*
     62  * Macro to test if we're using a GNU C compiler of a specific vintage
     63  * or later, for e.g. features that appeared in a particular version
     64  * of GNU C.  Usage:
     65  *
     66  *	#if __GNUC_PREREQ(major, minor)
     67  *	...cool feature...
     68  *	#else
     69  *	...delete feature...
     70  *	#endif
     71  */
     72 #ifdef __GNUC__
     73 #define	__GNUC_PREREQ(x, y)						\
     74 	((__GNUC__ == (x) && __GNUC_MINOR__ >= (y)) ||			\
     75 	 (__GNUC__ > (x)))
     76 #else
     77 #define	__GNUC_PREREQ(x, y)	0
     78 #endif
     79 
     80 #define __strong_alias(alias, sym) \
     81     __asm__(".global " #alias "\n" \
     82             #alias " = " #sym);
     83 
     84 #if defined(__cplusplus)
     85 #define	__BEGIN_DECLS		extern "C" {
     86 #define	__END_DECLS		}
     87 #define	__static_cast(x,y)	static_cast<x>(y)
     88 #else
     89 #define	__BEGIN_DECLS
     90 #define	__END_DECLS
     91 #define	__static_cast(x,y)	(x)y
     92 #endif
     93 
     94 /*
     95  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
     96  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
     97  * The __CONCAT macro is a bit tricky -- make sure you don't put spaces
     98  * in between its arguments.  __CONCAT can also concatenate double-quoted
     99  * strings produced by the __STRING macro, but this only works with ANSI C.
    100  */
    101 
    102 #define	___STRING(x)	__STRING(x)
    103 #define	___CONCAT(x,y)	__CONCAT(x,y)
    104 
    105 #if defined(__STDC__) || defined(__cplusplus)
    106 #define	__P(protos)	protos		/* full-blown ANSI C */
    107 #define	__CONCAT(x,y)	x ## y
    108 #define	__STRING(x)	#x
    109 
    110 #define	__const		const		/* define reserved names to standard */
    111 #define	__signed	signed
    112 #define	__volatile	volatile
    113 #if defined(__cplusplus)
    114 #define	__inline	inline		/* convert to C++ keyword */
    115 #else
    116 #if !defined(__GNUC__) && !defined(__lint__)
    117 #define	__inline			/* delete GCC keyword */
    118 #endif /* !__GNUC__  && !__lint__ */
    119 #endif /* !__cplusplus */
    120 
    121 #else	/* !(__STDC__ || __cplusplus) */
    122 #define	__P(protos)	()		/* traditional C preprocessor */
    123 #define	__CONCAT(x,y)	x/**/y
    124 #define	__STRING(x)	"x"
    125 
    126 #ifndef __GNUC__
    127 #define	__const				/* delete pseudo-ANSI C keywords */
    128 #define	__inline
    129 #define	__signed
    130 #define	__volatile
    131 #endif	/* !__GNUC__ */
    132 
    133 #endif	/* !(__STDC__ || __cplusplus) */
    134 
    135 /*
    136  * The following macro is used to remove const cast-away warnings
    137  * from gcc -Wcast-qual; it should be used with caution because it
    138  * can hide valid errors; in particular most valid uses are in
    139  * situations where the API requires it, not to cast away string
    140  * constants. We don't use *intptr_t on purpose here and we are
    141  * explicit about unsigned long so that we don't have additional
    142  * dependencies.
    143  */
    144 #define __UNCONST(a)	((void *)(unsigned long)(const void *)(a))
    145 
    146 #define __dead __attribute__((__noreturn__))
    147 #define __pure __attribute__((__const__))
    148 #define __pure2 __attribute__((__const__)) /* Android-added: used by FreeBSD libm */
    149 
    150 #define	__unused	__attribute__((__unused__))
    151 
    152 #define	__used		__attribute__((__used__))
    153 
    154 #define	__packed	__attribute__((__packed__))
    155 #define	__aligned(x)	__attribute__((__aligned__(x)))
    156 #define	__section(x)	__attribute__((__section__(x)))
    157 
    158 #define __statement(x)	__extension__(x)
    159 
    160 #define __nonnull(args) __attribute__((__nonnull__ args))
    161 
    162 #define __printflike(x, y) __attribute__((__format__(printf, x, y))) __nonnull((x))
    163 #define __scanflike(x, y) __attribute__((__format__(scanf, x, y))) __nonnull((x))
    164 
    165 /*
    166  * C99 defines the restrict type qualifier keyword.
    167  */
    168 #if defined(__STDC__VERSION__) && __STDC_VERSION__ >= 199901L
    169 #define	__restrict	restrict
    170 #endif
    171 
    172 /*
    173  * C99 defines __func__ predefined identifier.
    174  */
    175 #if !defined(__STDC_VERSION__) || !(__STDC_VERSION__ >= 199901L)
    176 #define	__func__	__PRETTY_FUNCTION__
    177 #endif /* !(__STDC_VERSION__ >= 199901L) */
    178 
    179 /*
    180  * GNU C version 2.96 adds explicit branch prediction so that
    181  * the CPU back-end can hint the processor and also so that
    182  * code blocks can be reordered such that the predicted path
    183  * sees a more linear flow, thus improving cache behavior, etc.
    184  *
    185  * The following two macros provide us with a way to use this
    186  * compiler feature.  Use __predict_true() if you expect the expression
    187  * to evaluate to true, and __predict_false() if you expect the
    188  * expression to evaluate to false.
    189  *
    190  * A few notes about usage:
    191  *
    192  *	* Generally, __predict_false() error condition checks (unless
    193  *	  you have some _strong_ reason to do otherwise, in which case
    194  *	  document it), and/or __predict_true() `no-error' condition
    195  *	  checks, assuming you want to optimize for the no-error case.
    196  *
    197  *	* Other than that, if you don't know the likelihood of a test
    198  *	  succeeding from empirical or other `hard' evidence, don't
    199  *	  make predictions.
    200  *
    201  *	* These are meant to be used in places that are run `a lot'.
    202  *	  It is wasteful to make predictions in code that is run
    203  *	  seldomly (e.g. at subsystem initialization time) as the
    204  *	  basic block reordering that this affects can often generate
    205  *	  larger code.
    206  */
    207 #define	__predict_true(exp)	__builtin_expect((exp) != 0, 1)
    208 #define	__predict_false(exp)	__builtin_expect((exp) != 0, 0)
    209 
    210 #define __noreturn    __attribute__((__noreturn__))
    211 #define __mallocfunc  __attribute__((malloc))
    212 #define __purefunc    __attribute__((pure))
    213 
    214 #define __always_inline __attribute__((__always_inline__))
    215 
    216 #define __wur __attribute__((__warn_unused_result__))
    217 
    218 #define __errorattr(msg) __attribute__((__error__(msg)))
    219 #define __warnattr(msg) __attribute__((__warning__(msg)))
    220 
    221 #define __errordecl(name, msg) extern void name(void) __errorattr(msg)
    222 
    223 /*
    224  * Some BSD source needs these macros.
    225  * Originally they embedded the rcs versions of each source file
    226  * in the generated binary. We strip strings during build anyway,.
    227  */
    228 #define __IDSTRING(_prefix,_s) /* nothing */
    229 #define __COPYRIGHT(_s) /* nothing */
    230 #define __FBSDID(_s) /* nothing */
    231 #define __RCSID(_s) /* nothing */
    232 #define __SCCSID(_s) /* nothing */
    233 
    234 /*
    235  * _BSD_SOURCE and _GNU_SOURCE are expected to be defined by callers before
    236  * any standard header file is included. In those header files we test
    237  * against __USE_BSD and __USE_GNU. glibc does this in <features.h> but we
    238  * do it in <sys/cdefs.h> instead because that's where our existing
    239  * _POSIX_C_SOURCE tests were, and we're already confident that <sys/cdefs.h>
    240  * is included everywhere it should be.
    241  *
    242  * The _GNU_SOURCE test needs to come before any _BSD_SOURCE or _POSIX* tests
    243  * because _GNU_SOURCE implies everything else.
    244  */
    245 #if defined(_GNU_SOURCE)
    246 # define __USE_GNU 1
    247 # undef _POSIX_SOURCE
    248 # define _POSIX_SOURCE 1
    249 # undef _POSIX_C_SOURCE
    250 # define _POSIX_C_SOURCE 200809L
    251 # undef _BSD_SOURCE
    252 # define _BSD_SOURCE 1
    253 #endif
    254 
    255 #if defined(_BSD_SOURCE)
    256 # define __USE_BSD 1
    257 #endif
    258 
    259 /*
    260  * _FILE_OFFSET_BITS 64 support.
    261  */
    262 #if !defined(__LP64__) && defined(_FILE_OFFSET_BITS)
    263 #if _FILE_OFFSET_BITS == 64
    264 #define __USE_FILE_OFFSET64 1
    265 #endif
    266 #endif
    267 
    268 /*-
    269  * POSIX.1 requires that the macros we test be defined before any standard
    270  * header file is included.
    271  *
    272  * Here's a quick run-down of the versions:
    273  *  defined(_POSIX_SOURCE)		1003.1-1988
    274  *  _POSIX_C_SOURCE == 1		1003.1-1990
    275  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
    276  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
    277  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
    278  *					and the omnibus ISO/IEC 9945-1: 1996
    279  *  _POSIX_C_SOURCE == 200112		1003.1-2001
    280  *  _POSIX_C_SOURCE == 200809		1003.1-2008
    281  *
    282  * In addition, the X/Open Portability Guide, which is now the Single UNIX
    283  * Specification, defines a feature-test macro which indicates the version of
    284  * that specification, and which subsumes _POSIX_C_SOURCE.
    285  *
    286  * Our macros begin with two underscores to avoid namespace screwage.
    287  */
    288 
    289 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
    290 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
    291 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
    292 #define	_POSIX_C_SOURCE		199009
    293 #endif
    294 
    295 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
    296 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
    297 #undef _POSIX_C_SOURCE
    298 #define	_POSIX_C_SOURCE		199209
    299 #endif
    300 
    301 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
    302 #ifdef _XOPEN_SOURCE
    303 #if _XOPEN_SOURCE - 0 >= 700
    304 #define	__XSI_VISIBLE		700
    305 #undef _POSIX_C_SOURCE
    306 #define	_POSIX_C_SOURCE		200809
    307 #elif _XOPEN_SOURCE - 0 >= 600
    308 #define	__XSI_VISIBLE		600
    309 #undef _POSIX_C_SOURCE
    310 #define	_POSIX_C_SOURCE		200112
    311 #elif _XOPEN_SOURCE - 0 >= 500
    312 #define	__XSI_VISIBLE		500
    313 #undef _POSIX_C_SOURCE
    314 #define	_POSIX_C_SOURCE		199506
    315 #endif
    316 #endif
    317 
    318 /*
    319  * Deal with all versions of POSIX.  The ordering relative to the tests above is
    320  * important.
    321  */
    322 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
    323 #define	_POSIX_C_SOURCE		198808
    324 #endif
    325 #ifdef _POSIX_C_SOURCE
    326 #if _POSIX_C_SOURCE >= 200809
    327 #define	__POSIX_VISIBLE		200809
    328 #define	__ISO_C_VISIBLE		1999
    329 #elif _POSIX_C_SOURCE >= 200112
    330 #define	__POSIX_VISIBLE		200112
    331 #define	__ISO_C_VISIBLE		1999
    332 #elif _POSIX_C_SOURCE >= 199506
    333 #define	__POSIX_VISIBLE		199506
    334 #define	__ISO_C_VISIBLE		1990
    335 #elif _POSIX_C_SOURCE >= 199309
    336 #define	__POSIX_VISIBLE		199309
    337 #define	__ISO_C_VISIBLE		1990
    338 #elif _POSIX_C_SOURCE >= 199209
    339 #define	__POSIX_VISIBLE		199209
    340 #define	__ISO_C_VISIBLE		1990
    341 #elif _POSIX_C_SOURCE >= 199009
    342 #define	__POSIX_VISIBLE		199009
    343 #define	__ISO_C_VISIBLE		1990
    344 #else
    345 #define	__POSIX_VISIBLE		198808
    346 #define	__ISO_C_VISIBLE		0
    347 #endif /* _POSIX_C_SOURCE */
    348 #else
    349 /*-
    350  * Deal with _ANSI_SOURCE:
    351  * If it is defined, and no other compilation environment is explicitly
    352  * requested, then define our internal feature-test macros to zero.  This
    353  * makes no difference to the preprocessor (undefined symbols in preprocessing
    354  * expressions are defined to have value zero), but makes it more convenient for
    355  * a test program to print out the values.
    356  *
    357  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
    358  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
    359  * environment (and in fact we will never get here).
    360  */
    361 #if defined(_ANSI_SOURCE)	/* Hide almost everything. */
    362 #define	__POSIX_VISIBLE		0
    363 #define	__XSI_VISIBLE		0
    364 #define	__BSD_VISIBLE		0
    365 #define	__ISO_C_VISIBLE		1990
    366 #elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
    367 #define	__POSIX_VISIBLE		0
    368 #define	__XSI_VISIBLE		0
    369 #define	__BSD_VISIBLE		0
    370 #define	__ISO_C_VISIBLE		1999
    371 #else				/* Default environment: show everything. */
    372 #define	__POSIX_VISIBLE		200809
    373 #define	__XSI_VISIBLE		700
    374 #define	__BSD_VISIBLE		1
    375 #define	__ISO_C_VISIBLE		1999
    376 #endif
    377 #endif
    378 
    379 /*
    380  * Default values.
    381  */
    382 #ifndef __XPG_VISIBLE
    383 # define __XPG_VISIBLE          700
    384 #endif
    385 #ifndef __POSIX_VISIBLE
    386 # define __POSIX_VISIBLE        200809
    387 #endif
    388 #ifndef __ISO_C_VISIBLE
    389 # define __ISO_C_VISIBLE        1999
    390 #endif
    391 #ifndef __BSD_VISIBLE
    392 # define __BSD_VISIBLE          1
    393 #endif
    394 
    395 #define  __BIONIC__   1
    396 #include <android/api-level.h>
    397 
    398 /* glibc compatibility. */
    399 #if __POSIX_VISIBLE >= 200809
    400 #define __USE_ISOC99 1
    401 #define __USE_XOPEN2K 1
    402 #define __USE_XOPEN2K8 1
    403 #endif
    404 #if __LP64__
    405 #define __WORDSIZE 64
    406 #else
    407 #define __WORDSIZE 32
    408 #endif
    409 
    410 /*
    411  * When _FORTIFY_SOURCE is defined, automatic bounds checking is
    412  * added to commonly used libc functions. If a buffer overrun is
    413  * detected, the program is safely aborted.
    414  *
    415  * See
    416  * http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html for details.
    417  */
    418 #if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && defined(__OPTIMIZE__) && __OPTIMIZE__ > 0
    419 #  define __BIONIC_FORTIFY 1
    420 #  if _FORTIFY_SOURCE == 2
    421 #    define __bos(s) __builtin_object_size((s), 1)
    422 #  else
    423 #    define __bos(s) __builtin_object_size((s), 0)
    424 #  endif
    425 #  define __bos0(s) __builtin_object_size((s), 0)
    426 #  define __BIONIC_FORTIFY_INLINE extern __inline__ __always_inline __attribute__((gnu_inline)) __attribute__((__artificial__))
    427 #endif
    428 #define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1)
    429 
    430 /* Used to tag non-static symbols that are private and never exposed by the shared library. */
    431 #define __LIBC_HIDDEN__ __attribute__((visibility("hidden")))
    432 
    433 /* Like __LIBC_HIDDEN__, but preserves binary compatibility for LP32. */
    434 #ifdef __LP64__
    435 #define __LIBC32_LEGACY_PUBLIC__ __LIBC_HIDDEN__
    436 #else
    437 #define __LIBC32_LEGACY_PUBLIC__ __LIBC_ABI_PUBLIC__
    438 #endif
    439 
    440 /* Used to tag non-static symbols that are public and exposed by the shared library. */
    441 #define __LIBC_ABI_PUBLIC__ __attribute__((visibility ("default")))
    442 
    443 /* Used to rename functions so that the compiler emits a call to 'x' rather than the function this was applied to. */
    444 #define __RENAME(x) __asm__(#x)
    445 
    446 #ifdef __clang__
    447 #define __AVAILABILITY(...) __attribute__((availability(android,__VA_ARGS__)))
    448 #define __INTRODUCED_IN(api_level) __AVAILABILITY(introduced=api_level)
    449 #define __DEPRECATED_IN(api_level) __AVAILABILITY(deprecated=api_level)
    450 #define __REMOVED_IN(api_level) __AVAILABILITY(obsoleted=api_level)
    451 #else
    452 #define __AVAILABILITY(...)
    453 #define __INTRODUCED_IN(api_level)
    454 #define __DEPRECATED_IN(api_level)
    455 #define __REMOVED_IN(api_level)
    456 #endif // __clang__
    457 
    458 #if __has_builtin(__builtin_umul_overflow) || __GNUC__ >= 5
    459 #if __LP64__
    460 #define __size_mul_overflow(a, b, result) __builtin_umull_overflow(a, b, result)
    461 #else
    462 #define __size_mul_overflow(a, b, result) __builtin_umul_overflow(a, b, result)
    463 #endif
    464 #else
    465 extern __inline__ __always_inline __attribute__((gnu_inline))
    466 int __size_mul_overflow(__SIZE_TYPE__ a, __SIZE_TYPE__ b, __SIZE_TYPE__ *result) {
    467     *result = a * b;
    468     static const __SIZE_TYPE__ mul_no_overflow = 1UL << (sizeof(__SIZE_TYPE__) * 4);
    469     return (a >= mul_no_overflow || b >= mul_no_overflow) && a > 0 && (__SIZE_TYPE__)-1 / a < b;
    470 }
    471 #endif
    472 
    473 #endif /* !_SYS_CDEFS_H_ */
    474