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))
__size_mul_overflow(__SIZE_TYPE__ a,__SIZE_TYPE__ b,__SIZE_TYPE__ * result)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