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 #pragma once 38 39 #define __BIONIC__ 1 40 41 #if defined(__cplusplus) 42 #define __BEGIN_DECLS extern "C" { 43 #define __END_DECLS } 44 #else 45 #define __BEGIN_DECLS 46 #define __END_DECLS 47 #endif 48 49 #define __strong_alias(alias, sym) \ 50 __asm__(".global " #alias "\n" \ 51 #alias " = " #sym); 52 53 #if defined(__cplusplus) 54 #define __BIONIC_CAST(_k,_t,_v) (_k<_t>(_v)) 55 #else 56 #define __BIONIC_CAST(_k,_t,_v) ((_t) (_v)) 57 #endif 58 59 #define __BIONIC_ALIGN(__value, __alignment) (((__value) + (__alignment)-1) & ~((__alignment)-1)) 60 61 /* 62 * The __CONCAT macro is used to concatenate parts of symbol names, e.g. 63 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo. 64 * The __CONCAT macro is a bit tricky -- make sure you don't put spaces 65 * in between its arguments. __CONCAT can also concatenate double-quoted 66 * strings produced by the __STRING macro, but this only works with ANSI C. 67 */ 68 69 #define __P(protos) protos /* full-blown ANSI C */ 70 71 #define __CONCAT1(x,y) x ## y 72 #define __CONCAT(x,y) __CONCAT1(x,y) 73 #define ___CONCAT(x,y) __CONCAT(x,y) 74 75 #define __STRING(x) #x 76 #define ___STRING(x) __STRING(x) 77 78 #if defined(__cplusplus) 79 #define __inline inline /* convert to C++ keyword */ 80 #endif /* !__cplusplus */ 81 82 #define __always_inline __attribute__((__always_inline__)) 83 #define __attribute_const__ __attribute__((__const__)) 84 #define __attribute_pure__ __attribute__((__pure__)) 85 #define __dead __attribute__((__noreturn__)) 86 #define __noreturn __attribute__((__noreturn__)) 87 #define __mallocfunc __attribute__((__malloc__)) 88 #define __packed __attribute__((__packed__)) 89 #define __unused __attribute__((__unused__)) 90 #define __used __attribute__((__used__)) 91 92 #define __printflike(x, y) __attribute__((__format__(printf, x, y))) 93 #define __scanflike(x, y) __attribute__((__format__(scanf, x, y))) 94 #define __strftimelike(x) __attribute__((__format__(strftime, x, 0))) 95 96 /* 97 * GNU C version 2.96 added explicit branch prediction so that 98 * the CPU back-end can hint the processor and also so that 99 * code blocks can be reordered such that the predicted path 100 * sees a more linear flow, thus improving cache behavior, etc. 101 * 102 * The following two macros provide us with a way to use this 103 * compiler feature. Use __predict_true() if you expect the expression 104 * to evaluate to true, and __predict_false() if you expect the 105 * expression to evaluate to false. 106 * 107 * A few notes about usage: 108 * 109 * * Generally, __predict_false() error condition checks (unless 110 * you have some _strong_ reason to do otherwise, in which case 111 * document it), and/or __predict_true() `no-error' condition 112 * checks, assuming you want to optimize for the no-error case. 113 * 114 * * Other than that, if you don't know the likelihood of a test 115 * succeeding from empirical or other `hard' evidence, don't 116 * make predictions. 117 * 118 * * These are meant to be used in places that are run `a lot'. 119 * It is wasteful to make predictions in code that is run 120 * seldomly (e.g. at subsystem initialization time) as the 121 * basic block reordering that this affects can often generate 122 * larger code. 123 */ 124 #define __predict_true(exp) __builtin_expect((exp) != 0, 1) 125 #define __predict_false(exp) __builtin_expect((exp) != 0, 0) 126 127 #define __wur __attribute__((__warn_unused_result__)) 128 129 #define __errorattr(msg) __attribute__((unavailable(msg))) 130 #define __warnattr(msg) __attribute__((deprecated(msg))) 131 #define __warnattr_real(msg) __attribute__((deprecated(msg))) 132 #define __enable_if(cond, msg) __attribute__((enable_if(cond, msg))) 133 #define __clang_error_if(cond, msg) __attribute__((diagnose_if(cond, msg, "error"))) 134 #define __clang_warning_if(cond, msg) __attribute__((diagnose_if(cond, msg, "warning"))) 135 136 #if defined(ANDROID_STRICT) 137 /* 138 * For things that are sketchy, but not necessarily an error. FIXME: Enable 139 * this. 140 */ 141 # define __warnattr_strict(msg) /* __warnattr(msg) */ 142 #else 143 # define __warnattr_strict(msg) 144 #endif 145 146 /* 147 * Some BSD source needs these macros. 148 * Originally they embedded the rcs versions of each source file 149 * in the generated binary. We strip strings during build anyway,. 150 */ 151 #define __IDSTRING(_prefix,_s) /* nothing */ 152 #define __COPYRIGHT(_s) /* nothing */ 153 #define __FBSDID(_s) /* nothing */ 154 #define __RCSID(_s) /* nothing */ 155 #define __SCCSID(_s) /* nothing */ 156 157 /* 158 * With bionic, you always get all C and POSIX API. 159 * 160 * If you want BSD and/or GNU extensions, _BSD_SOURCE and/or _GNU_SOURCE are 161 * expected to be defined by callers before *any* standard header file is 162 * included. 163 * 164 * In our header files we test against __USE_BSD and __USE_GNU. 165 */ 166 #if defined(_GNU_SOURCE) 167 # define __USE_BSD 1 168 # define __USE_GNU 1 169 #endif 170 171 #if defined(_BSD_SOURCE) 172 # define __USE_BSD 1 173 #endif 174 175 /* 176 * _FILE_OFFSET_BITS 64 support. 177 * See https://android.googlesource.com/platform/bionic/+/master/docs/32-bit-abi.md 178 */ 179 #if !defined(__LP64__) && defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64 180 # define __USE_FILE_OFFSET64 1 181 /* 182 * Note that __RENAME_IF_FILE_OFFSET64 is only valid if the off_t and off64_t 183 * functions were both added at the same API level because if you use this, 184 * you only have one declaration to attach __INTRODUCED_IN to. 185 */ 186 # define __RENAME_IF_FILE_OFFSET64(func) __RENAME(func) 187 #else 188 # define __RENAME_IF_FILE_OFFSET64(func) 189 #endif 190 191 /* 192 * For LP32, `long double` == `double`. Historically many `long double` functions were incorrect 193 * on x86, missing on most architectures, and even if they are present and correct, linking to 194 * them just bloats your ELF file by adding extra relocations. The __BIONIC_LP32_USE_LONG_DOUBLE 195 * macro lets us test the headers both ways (and adds an escape valve). 196 * 197 * Note that some functions have their __RENAME_LDBL commented out as a sign that although we could 198 * use __RENAME_LDBL it would actually cause the function to be introduced later because the 199 * `long double` variant appeared before the `double` variant. 200 */ 201 #if defined(__LP64__) || defined(__BIONIC_LP32_USE_LONG_DOUBLE) 202 #define __RENAME_LDBL(rewrite,rewrite_api_level,regular_api_level) __INTRODUCED_IN(regular_api_level) 203 #else 204 #define __RENAME_LDBL(rewrite,rewrite_api_level,regular_api_level) __RENAME(rewrite) __INTRODUCED_IN(rewrite_api_level) 205 #endif 206 207 /* 208 * On all architectures, `struct stat` == `struct stat64`, but LP32 didn't gain the *64 functions 209 * until API level 21. 210 */ 211 #if defined(__LP64__) || defined(__BIONIC_LP32_USE_STAT64) 212 #define __RENAME_STAT64(rewrite,rewrite_api_level,regular_api_level) __INTRODUCED_IN(regular_api_level) 213 #else 214 #define __RENAME_STAT64(rewrite,rewrite_api_level,regular_api_level) __RENAME(rewrite) __INTRODUCED_IN(rewrite_api_level) 215 #endif 216 217 /* glibc compatibility. */ 218 #if defined(__LP64__) 219 #define __WORDSIZE 64 220 #else 221 #define __WORDSIZE 32 222 #endif 223 224 /* 225 * When _FORTIFY_SOURCE is defined, automatic bounds checking is 226 * added to commonly used libc functions. If a buffer overrun is 227 * detected, the program is safely aborted. 228 * 229 * https://android-developers.googleblog.com/2017/04/fortify-in-android.html 230 */ 231 232 #define __BIONIC_FORTIFY_UNKNOWN_SIZE ((size_t) -1) 233 234 #if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 235 /* 236 * FORTIFY's _chk functions effectively disable ASAN's stdlib interceptors. 237 * Additionally, the static analyzer/clang-tidy try to pattern match some 238 * standard library functions, and FORTIFY sometimes interferes with this. So, 239 * we turn FORTIFY off in both cases. 240 */ 241 # if !__has_feature(address_sanitizer) && !defined(__clang_analyzer__) 242 # define __BIONIC_FORTIFY 1 243 # endif 244 #endif 245 246 // As we move some FORTIFY checks to be always on, __bos needs to be 247 // always available. 248 #if defined(__BIONIC_FORTIFY) 249 # if _FORTIFY_SOURCE == 2 250 # define __bos_level 1 251 # else 252 # define __bos_level 0 253 # endif 254 #else 255 # define __bos_level 0 256 #endif 257 258 #define __bosn(s, n) __builtin_object_size((s), (n)) 259 #define __bos(s) __bosn((s), __bos_level) 260 261 #if defined(__BIONIC_FORTIFY) 262 # define __bos0(s) __bosn((s), 0) 263 # define __pass_object_size_n(n) __attribute__((pass_object_size(n))) 264 /* 265 * FORTIFY'ed functions all have either enable_if or pass_object_size, which 266 * makes taking their address impossible. Saying (&read)(foo, bar, baz); will 267 * therefore call the unFORTIFYed version of read. 268 */ 269 # define __call_bypassing_fortify(fn) (&fn) 270 /* 271 * Because clang-FORTIFY uses overloads, we can't mark functions as `extern 272 * inline` without making them available externally. 273 */ 274 # define __BIONIC_FORTIFY_INLINE static __inline__ __always_inline 275 /* 276 * We should use __BIONIC_FORTIFY_VARIADIC instead of __BIONIC_FORTIFY_INLINE 277 * for variadic functions because compilers cannot inline them. 278 * The __always_inline attribute is useless, misleading, and could trigger 279 * clang compiler bug to incorrectly inline variadic functions. 280 */ 281 # define __BIONIC_FORTIFY_VARIADIC static __inline__ 282 /* Error functions don't have bodies, so they can just be static. */ 283 # define __BIONIC_ERROR_FUNCTION_VISIBILITY static __attribute__((unused)) 284 #else 285 /* Further increase sharing for some inline functions */ 286 # define __pass_object_size_n(n) 287 #endif 288 #define __pass_object_size __pass_object_size_n(__bos_level) 289 #define __pass_object_size0 __pass_object_size_n(0) 290 291 #if defined(__BIONIC_FORTIFY) || defined(__BIONIC_DECLARE_FORTIFY_HELPERS) 292 # define __BIONIC_INCLUDE_FORTIFY_HEADERS 1 293 #endif 294 295 #define __overloadable __attribute__((overloadable)) 296 297 /* Used to tag non-static symbols that are private and never exposed by the shared library. */ 298 #define __LIBC_HIDDEN__ __attribute__((visibility("hidden"))) 299 300 /* 301 * Used to tag symbols that should be hidden for 64-bit, 302 * but visible to preserve binary compatibility for LP32. 303 */ 304 #ifdef __LP64__ 305 #define __LIBC32_LEGACY_PUBLIC__ __attribute__((visibility("hidden"))) 306 #else 307 #define __LIBC32_LEGACY_PUBLIC__ __attribute__((visibility("default"))) 308 #endif 309 310 /* Used to rename functions so that the compiler emits a call to 'x' rather than the function this was applied to. */ 311 #define __RENAME(x) __asm__(#x) 312 313 #if __has_builtin(__builtin_umul_overflow) || __GNUC__ >= 5 314 #if defined(__LP64__) 315 #define __size_mul_overflow(a, b, result) __builtin_umull_overflow(a, b, result) 316 #else 317 #define __size_mul_overflow(a, b, result) __builtin_umul_overflow(a, b, result) 318 #endif 319 #else 320 extern __inline__ __always_inline __attribute__((gnu_inline)) 321 int __size_mul_overflow(__SIZE_TYPE__ a, __SIZE_TYPE__ b, __SIZE_TYPE__ *result) { 322 *result = a * b; 323 static const __SIZE_TYPE__ mul_no_overflow = 1UL << (sizeof(__SIZE_TYPE__) * 4); 324 return (a >= mul_no_overflow || b >= mul_no_overflow) && a > 0 && (__SIZE_TYPE__)-1 / a < b; 325 } 326 #endif 327 328 /* 329 * Used when we need to check for overflow when multiplying x and y. This 330 * should only be used where __size_mul_overflow can not work, because it makes 331 * assumptions that __size_mul_overflow doesn't (x and y are positive, ...), 332 * *and* doesn't make use of compiler intrinsics, so it's probably slower than 333 * __size_mul_overflow. 334 */ 335 #define __unsafe_check_mul_overflow(x, y) ((__SIZE_TYPE__)-1 / (x) < (y)) 336 337 #include <android/versioning.h> 338 #include <android/api-level.h> 339
