xref: /xnu-10063.101.15/bsd/sys/cdefs.h (revision 94d3b452840153a99b38a3a9659680b2a006908e)
1 /*
2  * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /* Copyright 1995 NeXT Computer, Inc. All rights reserved. */
29 /*
30  * Copyright (c) 1991, 1993
31  *	The Regents of the University of California.  All rights reserved.
32  *
33  * This code is derived from software contributed to Berkeley by
34  * Berkeley Software Design, Inc.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. All advertising materials mentioning features or use of this software
45  *    must display the following acknowledgement:
46  *	This product includes software developed by the University of
47  *	California, Berkeley and its contributors.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)cdefs.h	8.8 (Berkeley) 1/9/95
65  */
66 
67 #ifndef _CDEFS_H_
68 #define _CDEFS_H_
69 
70 #if defined(__cplusplus)
71 #define __BEGIN_DECLS   extern "C" {
72 #define __END_DECLS     }
73 #else
74 #define __BEGIN_DECLS
75 #define __END_DECLS
76 #endif
77 
78 /* This SDK is designed to work with clang and specific versions of
79  * gcc >= 4.0 with Apple's patch sets */
80 #if !defined(__GNUC__) || __GNUC__ < 4
81 #warning "Unsupported compiler detected"
82 #endif
83 
84 /*
85  * Compatibility with compilers and environments that don't support compiler
86  * feature checking function-like macros.
87  */
88 #ifndef __has_builtin
89 #define __has_builtin(x) 0
90 #endif
91 #ifndef __has_include
92 #define __has_include(x) 0
93 #endif
94 #ifndef __has_feature
95 #define __has_feature(x) 0
96 #endif
97 #ifndef __has_attribute
98 #define __has_attribute(x) 0
99 #endif
100 #ifndef __has_cpp_attribute
101 #define __has_cpp_attribute(x) 0
102 #endif
103 #ifndef __has_extension
104 #define __has_extension(x) 0
105 #endif
106 
107 /*
108  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
109  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
110  * The __CONCAT macro is a bit tricky -- make sure you don't put spaces
111  * in between its arguments.  __CONCAT can also concatenate double-quoted
112  * strings produced by the __STRING macro, but this only works with ANSI C.
113  */
114 #if defined(__STDC__) || defined(__cplusplus)
115 #define __P(protos)     protos          /* full-blown ANSI C */
116 #define __CONCAT(x, y)   x ## y
117 #define __STRING(x)     #x
118 
119 #define __const         const           /* define reserved names to standard */
120 #define __signed        signed
121 #define __volatile      volatile
122 #if defined(__cplusplus)
123 #define __inline        inline          /* convert to C++ keyword */
124 #else
125 #ifndef __GNUC__
126 #define __inline                        /* delete GCC keyword */
127 #endif /* !__GNUC__ */
128 #endif /* !__cplusplus */
129 
130 #else   /* !(__STDC__ || __cplusplus) */
131 #define __P(protos)     ()              /* traditional C preprocessor */
132 #define __CONCAT(x, y)   x /**/ y
133 #define __STRING(x)     "x"
134 
135 #ifndef __GNUC__
136 #define __const                         /* delete pseudo-ANSI C keywords */
137 #define __inline
138 #define __signed
139 #define __volatile
140 #endif  /* !__GNUC__ */
141 
142 /*
143  * In non-ANSI C environments, new programs will want ANSI-only C keywords
144  * deleted from the program and old programs will want them left alone.
145  * When using a compiler other than gcc, programs using the ANSI C keywords
146  * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
147  * When using "gcc -traditional", we assume that this is the intent; if
148  * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
149  */
150 #ifndef NO_ANSI_KEYWORDS
151 #define const           __const                 /* convert ANSI C keywords */
152 #define inline          __inline
153 #define signed          __signed
154 #define volatile        __volatile
155 #endif /* !NO_ANSI_KEYWORDS */
156 #endif /* !(__STDC__ || __cplusplus) */
157 
158 /*
159  * __pure2 can be used for functions that are only a function of their scalar
160  * arguments (meaning they can't dereference pointers).
161  *
162  * __stateful_pure can be used for functions that have no side effects,
163  * but depend on the state of the memory.
164  */
165 #define __dead2         __attribute__((__noreturn__))
166 #define __pure2         __attribute__((__const__))
167 #define __stateful_pure __attribute__((__pure__))
168 
169 /* __unused denotes variables and functions that may not be used, preventing
170  * the compiler from warning about it if not used.
171  */
172 #define __unused        __attribute__((__unused__))
173 
174 /* __used forces variables and functions to be included even if it appears
175  * to the compiler that they are not used (and would thust be discarded).
176  */
177 #define __used          __attribute__((__used__))
178 
179 /* __cold marks code used for debugging or that is rarely taken
180  * and tells the compiler to optimize for size and outline code.
181  */
182 #if __has_attribute(cold)
183 #define __cold          __attribute__((__cold__))
184 #else
185 #define __cold
186 #endif
187 
188 /* __returns_nonnull marks functions that return a non-null pointer. */
189 #if __has_attribute(returns_nonnull)
190 #define __returns_nonnull __attribute((returns_nonnull))
191 #else
192 #define __returns_nonnull
193 #endif
194 
195 /* __exported denotes symbols that should be exported even when symbols
196  * are hidden by default.
197  * __exported_push/_exported_pop are pragmas used to delimit a range of
198  *  symbols that should be exported even when symbols are hidden by default.
199  */
200 #define __exported      __attribute__((__visibility__("default")))
201 #define __exported_push _Pragma("GCC visibility push(default)")
202 #define __exported_pop  _Pragma("GCC visibility pop")
203 
204 /* __deprecated causes the compiler to produce a warning when encountering
205  * code using the deprecated functionality.
206  * __deprecated_msg() does the same, and compilers that support it will print
207  * a message along with the deprecation warning.
208  * This may require turning on such warning with the -Wdeprecated flag.
209  * __deprecated_enum_msg() should be used on enums, and compilers that support
210  * it will print the deprecation warning.
211  * __kpi_deprecated() specifically indicates deprecation of kernel programming
212  * interfaces in Kernel.framework used by KEXTs.
213  */
214 #define __deprecated    __attribute__((__deprecated__))
215 
216 #if __has_extension(attribute_deprecated_with_message) || \
217         (defined(__GNUC__) && ((__GNUC__ >= 5) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5))))
218 	#define __deprecated_msg(_msg) __attribute__((__deprecated__(_msg)))
219 #else
220 	#define __deprecated_msg(_msg) __attribute__((__deprecated__))
221 #endif
222 
223 #if __has_extension(enumerator_attributes)
224 	#define __deprecated_enum_msg(_msg) __deprecated_msg(_msg)
225 #else
226 	#define __deprecated_enum_msg(_msg)
227 #endif
228 
229 #if defined(KERNEL) && !defined(KERNEL_PRIVATE)
230 #define __kpi_deprecated(_msg) __deprecated_msg(_msg)
231 #else /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
232 #define __kpi_deprecated(_msg)
233 #endif /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
234 
235 /* __unavailable causes the compiler to error out when encountering
236  * code using the tagged function
237  */
238 #if __has_attribute(unavailable)
239 #define __unavailable __attribute__((__unavailable__))
240 #else
241 #define __unavailable
242 #endif
243 
244 #if defined(KERNEL) && !defined(KERNEL_PRIVATE)
245 #define __kpi_unavailable __unavailable
246 #else /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
247 #define __kpi_unavailable
248 #endif /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
249 
250 #if XNU_KERNEL_PRIVATE
251 /* This macro is meant to be used for kpi deprecated to x86 3rd parties
252  * but should be marked as unavailable for arm macOS devices.
253  * XNU:                         nothing (API is still available)
254  * 1st party kexts:             __deprecated
255  * 3rd party kexts macOS x86:   __deprecated
256  * 3rd party kexts macOS arm:   __unavailable
257  */
258 #define __kpi_deprecated_arm64_macos_unavailable
259 #elif !KERNEL || !XNU_PLATFORM_MacOSX
260 #define __kpi_deprecated_arm64_macos_unavailable
261 #elif KERNEL_PRIVATE
262 #define __kpi_deprecated_arm64_macos_unavailable __deprecated
263 #elif defined(__arm64__)
264 #define __kpi_deprecated_arm64_macos_unavailable __unavailable
265 #else
266 #define __kpi_deprecated_arm64_macos_unavailable __deprecated
267 #endif /* XNU_KERNEL_PRIVATE */
268 
269 /* Delete pseudo-keywords wherever they are not available or needed. */
270 #ifndef __dead
271 #define __dead
272 #define __pure
273 #endif
274 
275 /*
276  * We use `__restrict' as a way to define the `restrict' type qualifier
277  * without disturbing older software that is unaware of C99 keywords.
278  */
279 #if __STDC_VERSION__ < 199901
280 #define __restrict
281 #else
282 #define __restrict      restrict
283 #endif
284 
285 /* Compatibility with compilers and environments that don't support the
286  * nullability feature.
287  */
288 
289 #if !__has_feature(nullability)
290 #ifndef __nullable
291 #define __nullable
292 #endif
293 #ifndef __nonnull
294 #define __nonnull
295 #endif
296 #ifndef __null_unspecified
297 #define __null_unspecified
298 #endif
299 #ifndef _Nullable
300 #define _Nullable
301 #endif
302 #ifndef _Nonnull
303 #define _Nonnull
304 #endif
305 #ifndef _Null_unspecified
306 #define _Null_unspecified
307 #endif
308 #endif
309 
310 /*
311  * __disable_tail_calls causes the compiler to not perform tail call
312  * optimization inside the marked function.
313  */
314 #if __has_attribute(disable_tail_calls)
315 #define __disable_tail_calls    __attribute__((__disable_tail_calls__))
316 #else
317 #define __disable_tail_calls
318 #endif
319 
320 /*
321  * __not_tail_called causes the compiler to prevent tail call optimization
322  * on statically bound calls to the function.  It has no effect on indirect
323  * calls.  Virtual functions, objective-c methods, and functions marked as
324  * "always_inline" cannot be marked as __not_tail_called.
325  */
326 #if __has_attribute(not_tail_called)
327 #define __not_tail_called       __attribute__((__not_tail_called__))
328 #else
329 #define __not_tail_called
330 #endif
331 
332 /*
333  * __result_use_check warns callers of a function that not using the function
334  * return value is a bug, i.e. dismissing malloc() return value results in a
335  * memory leak.
336  */
337 #if __has_attribute(warn_unused_result)
338 #define __result_use_check __attribute__((__warn_unused_result__))
339 #else
340 #define __result_use_check
341 #endif
342 
343 /*
344  * __swift_unavailable causes the compiler to mark a symbol as specifically
345  * unavailable in Swift, regardless of any other availability in C.
346  */
347 #if __has_feature(attribute_availability_swift)
348 #define __swift_unavailable(_msg)       __attribute__((__availability__(swift, unavailable, message=_msg)))
349 #else
350 #define __swift_unavailable(_msg)
351 #endif
352 
353 /*
354  * __abortlike is the attribute to put on functions like abort() that are
355  * typically used to mark assertions. These optimize the codegen
356  * for outlining while still maintaining debugability.
357  */
358 #ifndef __abortlike
359 #define __abortlike __dead2 __cold __not_tail_called
360 #endif
361 
362 /* Declaring inline functions within headers is error-prone due to differences
363  * across various versions of the C language and extensions.  __header_inline
364  * can be used to declare inline functions within system headers.  In cases
365  * where you want to force inlining instead of letting the compiler make
366  * the decision, you can use __header_always_inline.
367  *
368  * Be aware that using inline for functions which compilers may also provide
369  * builtins can behave differently under various compilers.  If you intend to
370  * provide an inline version of such a function, you may want to use a macro
371  * instead.
372  *
373  * The check for !__GNUC__ || __clang__ is because gcc doesn't correctly
374  * support c99 inline in some cases:
375  * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55965
376  */
377 
378 #if defined(__cplusplus) || \
379         (__STDC_VERSION__ >= 199901L && \
380         !defined(__GNUC_GNU_INLINE__) && \
381         (!defined(__GNUC__) || defined(__clang__)))
382 # define __header_inline           inline
383 #elif defined(__GNUC__) && defined(__GNUC_STDC_INLINE__)
384 # define __header_inline           extern __inline __attribute__((__gnu_inline__))
385 #elif defined(__GNUC__)
386 # define __header_inline           extern __inline
387 #else
388 /* If we land here, we've encountered an unsupported compiler,
389  * so hopefully it understands static __inline as a fallback.
390  */
391 # define __header_inline           static __inline
392 #endif
393 
394 #ifdef __GNUC__
395 # define __header_always_inline    __header_inline __attribute__ ((__always_inline__))
396 #else
397 /* Unfortunately, we're using a compiler that we don't know how to force to
398  * inline.  Oh well.
399  */
400 # define __header_always_inline    __header_inline
401 #endif
402 
403 /*
404  * Compiler-dependent macros that bracket portions of code where the
405  * "-Wunreachable-code" warning should be ignored. Please use sparingly.
406  */
407 #if defined(__clang__)
408 # define __unreachable_ok_push \
409 	 _Pragma("clang diagnostic push") \
410 	 _Pragma("clang diagnostic ignored \"-Wunreachable-code\"")
411 # define __unreachable_ok_pop \
412 	 _Pragma("clang diagnostic pop")
413 #elif defined(__GNUC__) && ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
414 # define __unreachable_ok_push \
415 	 _Pragma("GCC diagnostic push") \
416 	 _Pragma("GCC diagnostic ignored \"-Wunreachable-code\"")
417 # define __unreachable_ok_pop \
418 	 _Pragma("GCC diagnostic pop")
419 #else
420 # define __unreachable_ok_push
421 # define __unreachable_ok_pop
422 #endif
423 
424 /*
425  * Compiler-dependent macros to declare that functions take printf-like
426  * or scanf-like arguments.  They are null except for versions of gcc
427  * that are known to support the features properly.  Functions declared
428  * with these attributes will cause compilation warnings if there is a
429  * mismatch between the format string and subsequent function parameter
430  * types.
431  */
432 #define __printflike(fmtarg, firstvararg) \
433 	__attribute__((__format__ (__printf__, fmtarg, firstvararg)))
434 #define __printf0like(fmtarg, firstvararg) \
435 	__attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
436 #define __scanflike(fmtarg, firstvararg) \
437 	__attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
438 #define __osloglike(fmtarg, firstvararg) \
439 	__attribute__((__format__ (__os_log__, fmtarg, firstvararg)))
440 
441 #define __IDSTRING(name, string) static const char name[] __used = string
442 
443 #ifndef __COPYRIGHT
444 #define __COPYRIGHT(s) __IDSTRING(copyright,s)
445 #endif
446 
447 #ifndef __RCSID
448 #define __RCSID(s) __IDSTRING(rcsid,s)
449 #endif
450 
451 #ifndef __SCCSID
452 #define __SCCSID(s) __IDSTRING(sccsid,s)
453 #endif
454 
455 #ifndef __PROJECT_VERSION
456 #define __PROJECT_VERSION(s) __IDSTRING(project_version,s)
457 #endif
458 
459 /* Source compatibility only, ID string not emitted in object file */
460 #ifndef __FBSDID
461 #define __FBSDID(s)
462 #endif
463 
464 #ifndef __DECONST
465 #define __DECONST(type, var)    __CAST_AWAY_QUALIFIER(var, const, type)
466 #endif
467 
468 #ifndef __DEVOLATILE
469 #define __DEVOLATILE(type, var) __CAST_AWAY_QUALIFIER(var, volatile, type)
470 #endif
471 
472 #ifndef __DEQUALIFY
473 #define __DEQUALIFY(type, var)  __CAST_AWAY_QUALIFIER(var, const volatile, type)
474 #endif
475 
476 /*
477  * __alloc_align can be used to label function arguments that represent the
478  * alignment of the returned pointer.
479  */
480 #ifndef __alloc_align
481 #if __has_attribute(alloc_align)
482 #define __alloc_align(n) __attribute__((alloc_align(n)))
483 #else
484 #define __alloc_align(n)
485 #endif
486 #endif // __alloc_align
487 
488 /*
489  * __alloc_size can be used to label function arguments that represent the
490  * size of memory that the function allocates and returns. The one-argument
491  * form labels a single argument that gives the allocation size (where the
492  * arguments are numbered from 1):
493  *
494  * void	*malloc(size_t __size) __alloc_size(1);
495  *
496  * The two-argument form handles the case where the size is calculated as the
497  * product of two arguments:
498  *
499  * void	*calloc(size_t __count, size_t __size) __alloc_size(1,2);
500  */
501 #ifndef __alloc_size
502 #if __has_attribute(alloc_size)
503 #define __alloc_size(...) __attribute__((alloc_size(__VA_ARGS__)))
504 #else
505 #define __alloc_size(...)
506 #endif
507 #endif // __alloc_size
508 
509 /*
510  * Facilities below assist adoption of -Wunsafe-buffer-usage, an off-by-default
511  * Clang compiler warning that helps the developer minimize unsafe, raw
512  * buffer manipulation in the code that may lead to buffer overflow
513  * vulnerabilities.
514  *
515  * They are primarily designed for modern C++ code where -Wunsafe-buffer-usage
516  * comes with automatic fix-it hints that help the developer transform
517  * their code to use modern C++ containers, which may be made bounds-safe by
518  * linking against a version of the C++ standard library that offers
519  * bounds-checked containers.
520  * They can be used in plain C, but -fbounds-safety is the preferred solution
521  * for plain C (see also <ptrcheck.h>).
522  *
523  * Attribute __unsafe_buffer_usage can be used to label functions that should be
524  * avoided as they may perform or otherwise introduce unsafe buffer
525  * manipulation operations.
526  *
527  * Calls to such functions are flagged by -Wunsafe-buffer-usage, similarly to
528  * how unchecked buffer manipulation operations are flagged when observed
529  * by the compiler directly:
530  *
531  *   // An unsafe function that needs to be avoided.
532  *   __unsafe_buffer_usage
533  *   void foo(int *buf, size_t size);
534  *
535  *   // A safe alternative to foo().
536  *   void foo(std::span<int> buf);
537  *
538  *   void bar(size_t idx) {
539  *       int array[5];
540  *
541  *       // Direct unsafe buffer manipulation through subscript operator:
542  *       array[idx] = 3;  // warning [-Wunsafe-buffer-usage]
543  *       // Unsafe buffer manipulation through function foo():
544  *       foo(array, 5);   // warning [-Wunsafe-buffer-usage]
545  *       // Checked buffer manipulation, with bounds information automatically
546  *       // preserved for the purposes of runtime checks in standard library:
547  *       foo(array);      // no warning
548  *   }
549  *
550  * While annotating a function as __unsafe_buffer_usage has an effect similar
551  * to annotating it as __deprecated, the __unsafe_buffer_usage attribute
552  * should be used whenever the resulting warning needs to be controlled
553  * by the -Wunsafe-buffer-usage flag (which is turned off in codebases that
554  * don't attempt to achieve bounds safety this way) as opposed to -Wdeprecated
555  * (enabled in most codebases).
556  *
557  * The attribute does NOT suppress -Wunsafe-buffer-usage warnings inside
558  * the function's body; it simply introduces new warnings at each call site
559  * to help the developers avoid the function entirely. Most of the time
560  * it does not make sense to annotate a function as __unsafe_buffer_usage
561  * without providing the users with a safe alternative.
562  *
563  * Pragmas __unsafe_buffer_usage_begin and __unsafe_buffer_usage_end
564  * annotate a range of code as intentionally containing unsafe buffer
565  * operations. They suppress -Wunsafe-buffer-usage warnings
566  * for unsafe operations in range:
567  *
568  *   __unsafe_buffer_usage_begin
569  *   array[idx] = 3; // warning suppressed
570  *   foo(array, 5);  // warning suppressed
571  *   __unsafe_buffer_usage_end
572  *
573  * These pragmas are NOT a way to mass-annotate functions with the attribute
574  * __unsafe_buffer_usage. Functions declared within the pragma range
575  * do NOT get annotated automatically. In some rare situations it makes sense
576  * to do all three: put the attribute on the function, put pragmas inside
577  * the body of the function, and put pragmas around some call sites.
578  */
579 #if __has_cpp_attribute(clang::unsafe_buffer_usage)
580 #define __has_safe_buffers 1
581 #define __unsafe_buffer_usage [[clang::unsafe_buffer_usage]]
582 #elif __has_attribute(unsafe_buffer_usage)
583 #define __has_safe_buffers 1
584 #define __unsafe_buffer_usage __attribute__((__unsafe_buffer_usage__))
585 #else
586 #define __has_safe_buffers 0
587 #define __unsafe_buffer_usage
588 #endif
589 #if __has_safe_buffers
590 #define __unsafe_buffer_usage_begin _Pragma("clang unsafe_buffer_usage begin")
591 #define __unsafe_buffer_usage_end   _Pragma("clang unsafe_buffer_usage end")
592 #else
593 #define __unsafe_buffer_usage_begin
594 #define __unsafe_buffer_usage_end
595 #endif
596 
597 /*
598  * COMPILATION ENVIRONMENTS -- see compat(5) for additional detail
599  *
600  * DEFAULT	By default newly complied code will get POSIX APIs plus
601  *		Apple API extensions in scope.
602  *
603  *		Most users will use this compilation environment to avoid
604  *		behavioral differences between 32 and 64 bit code.
605  *
606  * LEGACY	Defining _NONSTD_SOURCE will get pre-POSIX APIs plus Apple
607  *		API extensions in scope.
608  *
609  *		This is generally equivalent to the Tiger release compilation
610  *		environment, except that it cannot be applied to 64 bit code;
611  *		its use is discouraged.
612  *
613  *		We expect this environment to be deprecated in the future.
614  *
615  * STRICT	Defining _POSIX_C_SOURCE or _XOPEN_SOURCE restricts the
616  *		available APIs to exactly the set of APIs defined by the
617  *		corresponding standard, based on the value defined.
618  *
619  *		A correct, portable definition for _POSIX_C_SOURCE is 200112L.
620  *		A correct, portable definition for _XOPEN_SOURCE is 600L.
621  *
622  *		Apple API extensions are not visible in this environment,
623  *		which can cause Apple specific code to fail to compile,
624  *		or behave incorrectly if prototypes are not in scope or
625  *		warnings about missing prototypes are not enabled or ignored.
626  *
627  * In any compilation environment, for correct symbol resolution to occur,
628  * function prototypes must be in scope.  It is recommended that all Apple
629  * tools users add either the "-Wall" or "-Wimplicit-function-declaration"
630  * compiler flags to their projects to be warned when a function is being
631  * used without a prototype in scope.
632  */
633 
634 /* These settings are particular to each product. */
635 #ifdef KERNEL
636 #define __DARWIN_ONLY_64_BIT_INO_T      0
637 #define __DARWIN_ONLY_UNIX_CONFORMANCE  0
638 #define __DARWIN_ONLY_VERS_1050         0
639 #if defined(__x86_64__)
640 #define __DARWIN_SUF_DARWIN14   "_darwin14"
641 #define __DARWIN14_ALIAS(sym)   __asm("_" __STRING(sym) __DARWIN_SUF_DARWIN14)
642 #else
643 #define __DARWIN14_ALIAS(sym)
644 #endif
645 #else /* !KERNEL */
646 #ifdef XNU_PLATFORM_iPhoneOS
647 /* Platform: iPhoneOS */
648 #define __DARWIN_ONLY_64_BIT_INO_T      1
649 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
650 #define __DARWIN_ONLY_VERS_1050         1
651 #endif /* XNU_PLATFORM_iPhoneOS */
652 #ifdef XNU_PLATFORM_iPhoneSimulator
653 /* Platform: iPhoneSimulator */
654 #define __DARWIN_ONLY_64_BIT_INO_T      1
655 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
656 #define __DARWIN_ONLY_VERS_1050         1
657 #endif /* XNU_PLATFORM_iPhoneSimulator */
658 #ifdef XNU_PLATFORM_tvOS
659 /* Platform: tvOS */
660 #define __DARWIN_ONLY_64_BIT_INO_T      1
661 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
662 #define __DARWIN_ONLY_VERS_1050         1
663 #endif /* XNU_PLATFORM_tvOS */
664 #ifdef XNU_PLATFORM_AppleTVOS
665 /* Platform: AppleTVOS */
666 #define __DARWIN_ONLY_64_BIT_INO_T      1
667 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
668 #define __DARWIN_ONLY_VERS_1050         1
669 #endif /* XNU_PLATFORM_AppleTVOS */
670 #ifdef XNU_PLATFORM_tvSimulator
671 /* Platform: tvSimulator */
672 #define __DARWIN_ONLY_64_BIT_INO_T      1
673 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
674 #define __DARWIN_ONLY_VERS_1050         1
675 #endif /* XNU_PLATFORM_tvSimulator */
676 #ifdef XNU_PLATFORM_AppleTVSimulator
677 /* Platform: AppleTVSimulator */
678 #define __DARWIN_ONLY_64_BIT_INO_T      1
679 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
680 #define __DARWIN_ONLY_VERS_1050         1
681 #endif /* XNU_PLATFORM_AppleTVSimulator */
682 #ifdef XNU_PLATFORM_iPhoneOSNano
683 /* Platform: iPhoneOSNano */
684 #define __DARWIN_ONLY_64_BIT_INO_T      1
685 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
686 #define __DARWIN_ONLY_VERS_1050         1
687 #endif /* XNU_PLATFORM_iPhoneOSNano */
688 #ifdef XNU_PLATFORM_iPhoneNanoSimulator
689 /* Platform: iPhoneNanoSimulator */
690 #define __DARWIN_ONLY_64_BIT_INO_T      1
691 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
692 #define __DARWIN_ONLY_VERS_1050         1
693 #endif /* XNU_PLATFORM_iPhoneNanoSimulator */
694 #ifdef XNU_PLATFORM_WatchOS
695 /* Platform: WatchOS */
696 #define __DARWIN_ONLY_64_BIT_INO_T      1
697 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
698 #define __DARWIN_ONLY_VERS_1050         1
699 #endif /* XNU_PLATFORM_WatchOS */
700 #ifdef XNU_PLATFORM_WatchSimulator
701 /* Platform: WatchSimulator */
702 #define __DARWIN_ONLY_64_BIT_INO_T      1
703 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
704 #define __DARWIN_ONLY_VERS_1050         1
705 #endif /* XNU_PLATFORM_WatchSimulator */
706 #ifdef XNU_PLATFORM_BridgeOS
707 /* Platform: BridgeOS */
708 #define __DARWIN_ONLY_64_BIT_INO_T      1
709 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
710 #define __DARWIN_ONLY_VERS_1050         1
711 #endif /* XNU_PLATFORM_BridgeOS */
712 #ifdef XNU_PLATFORM_DriverKit
713 /* Platform: DriverKit */
714 #define __DARWIN_ONLY_64_BIT_INO_T      1
715 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
716 #define __DARWIN_ONLY_VERS_1050         1
717 #endif /* XNU_PLATFORM_DriverKit */
718 #ifdef XNU_PLATFORM_MacOSX
719 /* Platform: MacOSX */
720 #if defined(__i386__)
721 #define __DARWIN_ONLY_64_BIT_INO_T      0
722 #define __DARWIN_ONLY_UNIX_CONFORMANCE  0
723 #define __DARWIN_ONLY_VERS_1050         0
724 #elif defined(__x86_64__)
725 #define __DARWIN_ONLY_64_BIT_INO_T      0
726 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
727 #define __DARWIN_ONLY_VERS_1050         0
728 #else
729 #define __DARWIN_ONLY_64_BIT_INO_T      1
730 #define __DARWIN_ONLY_UNIX_CONFORMANCE  1
731 #define __DARWIN_ONLY_VERS_1050         1
732 #endif
733 #endif /* XNU_PLATFORM_MacOSX */
734 #endif /* KERNEL */
735 
736 /*
737  * The __DARWIN_ALIAS macros are used to do symbol renaming; they allow
738  * legacy code to use the old symbol, thus maintaining binary compatibility
739  * while new code can use a standards compliant version of the same function.
740  *
741  * __DARWIN_ALIAS is used by itself if the function signature has not
742  * changed, it is used along with a #ifdef check for __DARWIN_UNIX03
743  * if the signature has changed.  Because the __LP64__ environment
744  * only supports UNIX03 semantics it causes __DARWIN_UNIX03 to be
745  * defined, but causes __DARWIN_ALIAS to do no symbol mangling.
746  *
747  * As a special case, when XCode is used to target a specific version of the
748  * OS, the manifest constant __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__
749  * will be defined by the compiler, with the digits representing major version
750  * time 100 + minor version times 10 (e.g. 10.5 := 1050).  If we are targeting
751  * pre-10.5, and it is the default compilation environment, revert the
752  * compilation environment to pre-__DARWIN_UNIX03.
753  */
754 #if !defined(__DARWIN_UNIX03)
755 #  if defined(KERNEL)
756 #    define __DARWIN_UNIX03     0
757 #  elif __DARWIN_ONLY_UNIX_CONFORMANCE
758 #    if defined(_NONSTD_SOURCE)
759 #      error "Can't define _NONSTD_SOURCE when only UNIX conformance is available."
760 #    endif /* _NONSTD_SOURCE */
761 #    define __DARWIN_UNIX03     1
762 #  elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1040)
763 #    define __DARWIN_UNIX03     0
764 #  elif defined(_DARWIN_C_SOURCE) || defined(_XOPEN_SOURCE) || defined(_POSIX_C_SOURCE)
765 #    if defined(_NONSTD_SOURCE)
766 #      error "Can't define both _NONSTD_SOURCE and any of _DARWIN_C_SOURCE, _XOPEN_SOURCE or _POSIX_C_SOURCE."
767 #    endif /* _NONSTD_SOURCE */
768 #    define __DARWIN_UNIX03     1
769 #  elif defined(_NONSTD_SOURCE)
770 #    define __DARWIN_UNIX03     0
771 #  else /* default */
772 #    if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1050)
773 #      define __DARWIN_UNIX03   0
774 #    else /* __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1050 */
775 #      define __DARWIN_UNIX03   1
776 #    endif /* __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1050 */
777 #  endif /* _DARWIN_C_SOURCE || _XOPEN_SOURCE || _POSIX_C_SOURCE || __LP64__ */
778 #endif /* !__DARWIN_UNIX03 */
779 
780 #if !defined(__DARWIN_64_BIT_INO_T)
781 #  if defined(KERNEL)
782 #    define __DARWIN_64_BIT_INO_T 0
783 #  elif defined(_DARWIN_USE_64_BIT_INODE)
784 #    if defined(_DARWIN_NO_64_BIT_INODE)
785 #      error "Can't define both _DARWIN_USE_64_BIT_INODE and _DARWIN_NO_64_BIT_INODE."
786 #    endif /* _DARWIN_NO_64_BIT_INODE */
787 #    define __DARWIN_64_BIT_INO_T 1
788 #  elif defined(_DARWIN_NO_64_BIT_INODE)
789 #    if __DARWIN_ONLY_64_BIT_INO_T
790 #      error "Can't define _DARWIN_NO_64_BIT_INODE when only 64-bit inodes are available."
791 #    endif /* __DARWIN_ONLY_64_BIT_INO_T */
792 #    define __DARWIN_64_BIT_INO_T 0
793 #  else /* default */
794 #    if __DARWIN_ONLY_64_BIT_INO_T
795 #      define __DARWIN_64_BIT_INO_T 1
796 #    elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1060) || __DARWIN_UNIX03 == 0
797 #      define __DARWIN_64_BIT_INO_T 0
798 #    else /* default */
799 #      define __DARWIN_64_BIT_INO_T 1
800 #    endif /* __DARWIN_ONLY_64_BIT_INO_T */
801 #  endif
802 #endif /* !__DARWIN_64_BIT_INO_T */
803 
804 #if !defined(__DARWIN_VERS_1050)
805 #  if defined(KERNEL)
806 #    define __DARWIN_VERS_1050 0
807 #  elif __DARWIN_ONLY_VERS_1050
808 #    define __DARWIN_VERS_1050 1
809 #  elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1050) || __DARWIN_UNIX03 == 0
810 #    define __DARWIN_VERS_1050 0
811 #  else /* default */
812 #    define __DARWIN_VERS_1050 1
813 #  endif
814 #endif /* !__DARWIN_VERS_1050 */
815 
816 #if !defined(__DARWIN_NON_CANCELABLE)
817 #  if defined(KERNEL)
818 #    define __DARWIN_NON_CANCELABLE 0
819 #  else /* default */
820 #    define __DARWIN_NON_CANCELABLE 0
821 #  endif
822 #endif /* !__DARWIN_NON_CANCELABLE */
823 
824 /*
825  * symbol suffixes used for symbol versioning
826  */
827 #if __DARWIN_UNIX03
828 #  if __DARWIN_ONLY_UNIX_CONFORMANCE
829 #    define __DARWIN_SUF_UNIX03         /* nothing */
830 #  else /* !__DARWIN_ONLY_UNIX_CONFORMANCE */
831 #    define __DARWIN_SUF_UNIX03         "$UNIX2003"
832 #  endif /* __DARWIN_ONLY_UNIX_CONFORMANCE */
833 
834 #  if __DARWIN_64_BIT_INO_T
835 #    if __DARWIN_ONLY_64_BIT_INO_T
836 #      define __DARWIN_SUF_64_BIT_INO_T /* nothing */
837 #    else /* !__DARWIN_ONLY_64_BIT_INO_T */
838 #      define __DARWIN_SUF_64_BIT_INO_T "$INODE64"
839 #    endif /* __DARWIN_ONLY_64_BIT_INO_T */
840 #  else /* !__DARWIN_64_BIT_INO_T */
841 #    define __DARWIN_SUF_64_BIT_INO_T   /* nothing */
842 #  endif /* __DARWIN_64_BIT_INO_T */
843 
844 #  if __DARWIN_VERS_1050
845 #    if __DARWIN_ONLY_VERS_1050
846 #      define __DARWIN_SUF_1050         /* nothing */
847 #    else /* !__DARWIN_ONLY_VERS_1050 */
848 #      define __DARWIN_SUF_1050         "$1050"
849 #    endif /* __DARWIN_ONLY_VERS_1050 */
850 #  else /* !__DARWIN_VERS_1050 */
851 #    define __DARWIN_SUF_1050           /* nothing */
852 #  endif /* __DARWIN_VERS_1050 */
853 
854 #  if __DARWIN_NON_CANCELABLE
855 #    define __DARWIN_SUF_NON_CANCELABLE "$NOCANCEL"
856 #  else /* !__DARWIN_NON_CANCELABLE */
857 #    define __DARWIN_SUF_NON_CANCELABLE /* nothing */
858 #  endif /* __DARWIN_NON_CANCELABLE */
859 
860 #else /* !__DARWIN_UNIX03 */
861 #  define __DARWIN_SUF_UNIX03           /* nothing */
862 #  define __DARWIN_SUF_64_BIT_INO_T     /* nothing */
863 #  define __DARWIN_SUF_NON_CANCELABLE   /* nothing */
864 #  define __DARWIN_SUF_1050             /* nothing */
865 #endif /* __DARWIN_UNIX03 */
866 
867 #define __DARWIN_SUF_EXTSN              "$DARWIN_EXTSN"
868 
869 /*
870  * symbol versioning macros
871  */
872 #define __DARWIN_ALIAS(sym)             __asm("_" __STRING(sym) __DARWIN_SUF_UNIX03)
873 #define __DARWIN_ALIAS_C(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_NON_CANCELABLE __DARWIN_SUF_UNIX03)
874 #define __DARWIN_ALIAS_I(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_64_BIT_INO_T __DARWIN_SUF_UNIX03)
875 #define __DARWIN_NOCANCEL(sym)          __asm("_" __STRING(sym) __DARWIN_SUF_NON_CANCELABLE)
876 #define __DARWIN_INODE64(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_64_BIT_INO_T)
877 
878 #define __DARWIN_1050(sym)              __asm("_" __STRING(sym) __DARWIN_SUF_1050)
879 #define __DARWIN_1050ALIAS(sym)         __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_UNIX03)
880 #define __DARWIN_1050ALIAS_C(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_NON_CANCELABLE __DARWIN_SUF_UNIX03)
881 #define __DARWIN_1050ALIAS_I(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_64_BIT_INO_T __DARWIN_SUF_UNIX03)
882 #define __DARWIN_1050INODE64(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_64_BIT_INO_T)
883 
884 #define __DARWIN_EXTSN(sym)             __asm("_" __STRING(sym) __DARWIN_SUF_EXTSN)
885 #define __DARWIN_EXTSN_C(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_EXTSN __DARWIN_SUF_NON_CANCELABLE)
886 #if XNU_KERNEL_PRIVATE
887 #define __XNU_INTERNAL(sym)             __asm("_" __STRING(sym) "$XNU_INTERNAL") __attribute__((used))
888 #endif
889 
890 /*
891  * symbol release macros
892  */
893 #ifdef KERNEL
894 #define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)
895 #else
896 #include <sys/_symbol_aliasing.h>
897 
898 #if defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
899 #define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   __DARWIN_ALIAS_STARTING_IPHONE_##_iphone(x)
900 #elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
901 #define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   __DARWIN_ALIAS_STARTING_MAC_##_mac(x)
902 #else
903 #define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   x
904 #endif
905 #endif /* KERNEL */
906 
907 
908 /*
909  * POSIX.1 requires that the macros we test be defined before any standard
910  * header file is included.  This permits us to convert values for feature
911  * testing, as necessary, using only _POSIX_C_SOURCE.
912  *
913  * Here's a quick run-down of the versions:
914  *  defined(_POSIX_SOURCE)		1003.1-1988
915  *  _POSIX_C_SOURCE == 1L		1003.1-1990
916  *  _POSIX_C_SOURCE == 2L		1003.2-1992 C Language Binding Option
917  *  _POSIX_C_SOURCE == 199309L		1003.1b-1993
918  *  _POSIX_C_SOURCE == 199506L		1003.1c-1995, 1003.1i-1995,
919  *					and the omnibus ISO/IEC 9945-1: 1996
920  *  _POSIX_C_SOURCE == 200112L		1003.1-2001
921  *  _POSIX_C_SOURCE == 200809L		1003.1-2008
922  *
923  * In addition, the X/Open Portability Guide, which is now the Single UNIX
924  * Specification, defines a feature-test macro which indicates the version of
925  * that specification, and which subsumes _POSIX_C_SOURCE.
926  */
927 
928 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1L. */
929 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1L
930 #undef _POSIX_C_SOURCE
931 #define _POSIX_C_SOURCE         199009L
932 #endif
933 
934 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2L. */
935 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2L
936 #undef _POSIX_C_SOURCE
937 #define _POSIX_C_SOURCE         199209L
938 #endif
939 
940 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
941 #ifdef _XOPEN_SOURCE
942 #if _XOPEN_SOURCE - 0L >= 700L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 200809L)
943 #undef _POSIX_C_SOURCE
944 #define _POSIX_C_SOURCE         200809L
945 #elif _XOPEN_SOURCE - 0L >= 600L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 200112L)
946 #undef _POSIX_C_SOURCE
947 #define _POSIX_C_SOURCE         200112L
948 #elif _XOPEN_SOURCE - 0L >= 500L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 199506L)
949 #undef _POSIX_C_SOURCE
950 #define _POSIX_C_SOURCE         199506L
951 #endif
952 #endif
953 
954 /*
955  * Deal with all versions of POSIX.  The ordering relative to the tests above is
956  * important.
957  */
958 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
959 #define _POSIX_C_SOURCE         198808L
960 #endif
961 
962 /* POSIX C deprecation macros */
963 #ifdef KERNEL
964 #define __POSIX_C_DEPRECATED(ver)
965 #else
966 #include <sys/_posix_availability.h>
967 
968 #define __POSIX_C_DEPRECATED(ver) ___POSIX_C_DEPRECATED_STARTING_##ver
969 #endif
970 
971 /*
972  * Set a single macro which will always be defined and can be used to determine
973  * the appropriate namespace.  For POSIX, these values will correspond to
974  * _POSIX_C_SOURCE value.  Currently there are two additional levels corresponding
975  * to ANSI (_ANSI_SOURCE) and Darwin extensions (_DARWIN_C_SOURCE)
976  */
977 #define __DARWIN_C_ANSI         010000L
978 #define __DARWIN_C_FULL         900000L
979 
980 #if   defined(_ANSI_SOURCE)
981 #define __DARWIN_C_LEVEL        __DARWIN_C_ANSI
982 #elif defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE) && !defined(_NONSTD_SOURCE)
983 #define __DARWIN_C_LEVEL        _POSIX_C_SOURCE
984 #else
985 #define __DARWIN_C_LEVEL        __DARWIN_C_FULL
986 #endif
987 
988 /* If the developer has neither requested a strict language mode nor a version
989  * of POSIX, turn on functionality provided by __STDC_WANT_LIB_EXT1__ as part
990  * of __DARWIN_C_FULL.
991  */
992 #if !defined(__STDC_WANT_LIB_EXT1__) && !defined(__STRICT_ANSI__) && __DARWIN_C_LEVEL >= __DARWIN_C_FULL
993 #define __STDC_WANT_LIB_EXT1__ 1
994 #endif
995 
996 /*
997  * long long is not supported in c89 (__STRICT_ANSI__), but g++ -ansi and
998  * c99 still want long longs.  While not perfect, we allow long longs for
999  * g++.
1000  */
1001 #if (defined(__STRICT_ANSI__) && (__STDC_VERSION__ - 0 < 199901L) && !defined(__GNUG__))
1002 #define __DARWIN_NO_LONG_LONG 1
1003 #else
1004 #define __DARWIN_NO_LONG_LONG 0
1005 #endif
1006 
1007 /*****************************************
1008 *  Public darwin-specific feature macros
1009 *****************************************/
1010 
1011 /*
1012  * _DARWIN_FEATURE_64_BIT_INODE indicates that the ino_t type is 64-bit, and
1013  * structures modified for 64-bit inodes (like struct stat) will be used.
1014  */
1015 #if __DARWIN_64_BIT_INO_T
1016 #define _DARWIN_FEATURE_64_BIT_INODE            1
1017 #endif
1018 
1019 /*
1020  * _DARWIN_FEATURE_64_ONLY_BIT_INODE indicates that the ino_t type may only
1021  * be 64-bit; there is no support for 32-bit ino_t when this macro is defined
1022  * (and non-zero).  There is no struct stat64 either, as the regular
1023  * struct stat will already be the 64-bit version.
1024  */
1025 #if __DARWIN_ONLY_64_BIT_INO_T
1026 #define _DARWIN_FEATURE_ONLY_64_BIT_INODE       1
1027 #endif
1028 
1029 /*
1030  * _DARWIN_FEATURE_ONLY_VERS_1050 indicates that only those APIs updated
1031  * in 10.5 exists; no pre-10.5 variants are available.
1032  */
1033 #if __DARWIN_ONLY_VERS_1050
1034 #define _DARWIN_FEATURE_ONLY_VERS_1050          1
1035 #endif
1036 
1037 /*
1038  * _DARWIN_FEATURE_ONLY_UNIX_CONFORMANCE indicates only UNIX conforming API
1039  * are available (the legacy BSD APIs are not available)
1040  */
1041 #if __DARWIN_ONLY_UNIX_CONFORMANCE
1042 #define _DARWIN_FEATURE_ONLY_UNIX_CONFORMANCE   1
1043 #endif
1044 
1045 /*
1046  * _DARWIN_FEATURE_UNIX_CONFORMANCE indicates whether UNIX conformance is on,
1047  * and specifies the conformance level (3 is SUSv3)
1048  */
1049 #if __DARWIN_UNIX03
1050 #define _DARWIN_FEATURE_UNIX_CONFORMANCE        3
1051 #endif
1052 
1053 #if defined(DRIVERKIT) && !defined(KERNEL)
1054 /*
1055  * __DRIVERKIT_LIBC__ indicates to the C++ standard library headers and
1056  * similar components that only the restricted set of standard C library
1057  * functionality and headers for the DriverKit userspace driver environment
1058  * are available.
1059  */
1060 #define __DRIVERKIT_LIBC__                      1
1061 #endif /* defined(DRIVERKIT) && !defined(KERNEL) */
1062 
1063 /*
1064  * This macro casts away the qualifier from the variable
1065  *
1066  * Note: use at your own risk, removing qualifiers can result in
1067  * catastrophic run-time failures.
1068  */
1069 #ifndef __CAST_AWAY_QUALIFIER
1070 /*
1071  * XXX: this shouldn't ignore anything more than -Wcast-qual,
1072  * but the old implementation made it an almighty cast that
1073  * ignored everything, so things break left and right if you
1074  * make it only ignore -Wcast-qual.
1075  */
1076 #define __CAST_AWAY_QUALIFIER(variable, qualifier, type) \
1077 	_Pragma("GCC diagnostic push") \
1078 	_Pragma("GCC diagnostic ignored \"-Wcast-qual\"") \
1079 	_Pragma("GCC diagnostic ignored \"-Wcast-align\"") \
1080 	_Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"") \
1081 	((type)(variable)) \
1082 	_Pragma("GCC diagnostic pop")
1083 #endif
1084 
1085 /*
1086  * __XNU_PRIVATE_EXTERN is a linkage decoration indicating that a symbol can be
1087  * used from other compilation units, but not other libraries or executables.
1088  */
1089 #ifndef __XNU_PRIVATE_EXTERN
1090 #define __XNU_PRIVATE_EXTERN __attribute__((visibility("hidden")))
1091 #endif
1092 
1093 #if __has_include(<ptrcheck.h>)
1094 #include <ptrcheck.h>
1095 #else
1096 /*
1097  * We intentionally define to nothing pointer attributes which do not have an
1098  * impact on the ABI. __indexable and __bidi_indexable are not defined because
1099  * of the ABI incompatibility that makes the diagnostic preferable.
1100  */
1101 #define __has_ptrcheck 0
1102 #define __single
1103 #define __unsafe_indexable
1104 #define __counted_by(N)
1105 #define __sized_by(N)
1106 #define __ended_by(E)
1107 #define __terminated_by(T)
1108 #define __null_terminated
1109 
1110 /*
1111  * Similarly, we intentionally define to nothing the
1112  * __ptrcheck_abi_assume_single and __ptrcheck_abi_assume_unsafe_indexable
1113  * macros because they do not lead to an ABI incompatibility. However, we do not
1114  * define the indexable and unsafe_indexable ones because the diagnostic is
1115  * better than the silent ABI break.
1116  */
1117 #define __ptrcheck_abi_assume_single()
1118 #define __ptrcheck_abi_assume_unsafe_indexable()
1119 
1120 /* __unsafe_forge intrinsics are defined as regular C casts. */
1121 #define __unsafe_forge_bidi_indexable(T, P, S) ((T)(P))
1122 #define __unsafe_forge_single(T, P) ((T)(P))
1123 #define __unsafe_forge_terminated_by(T, P, E) ((T)(P))
1124 #define __unsafe_forge_null_terminated(T, P) ((T)(P))
1125 #define __terminated_by_to_indexable(P) (P)
1126 #define __unsafe_terminated_by_to_indexable(P) (P)
1127 #define __null_terminated_to_indexable(P) (P)
1128 #define __unsafe_null_terminated_to_indexable(P) (P)
1129 #define __unsafe_terminated_by_from_indexable(T, P, ...) (P)
1130 #define __unsafe_null_terminated_from_indexable(P, ...) (P)
1131 
1132 /* decay operates normally; attribute is meaningless without pointer checks. */
1133 #define __array_decay_dicards_count_in_parameters
1134 
1135 /* this is a write-once variable; not useful without pointer checks. */
1136 #define __unsafe_late_const
1137 
1138 #define __ptrcheck_unavailable
1139 #define __ptrcheck_unavailable_r(REPLACEMENT)
1140 
1141 #endif /* !__has_include(<ptrcheck.h>) */
1142 
1143 #if KERNEL && !BOUND_CHECKS && !__has_ptrcheck
1144 /*
1145  * With pointer checks disabled, we define __indexable to allow source to still
1146  * contain these annotations. This is safe in builds which _uniformly_ disable
1147  * pointer checks (but not in builds which inconsistently have them enabled).
1148  */
1149 
1150 #define __indexable
1151 #define __bidi_indexable
1152 #endif
1153 
1154 #define __ASSUME_PTR_ABI_SINGLE_BEGIN       __ptrcheck_abi_assume_single()
1155 #define __ASSUME_PTR_ABI_SINGLE_END         __ptrcheck_abi_assume_unsafe_indexable()
1156 
1157 #if __has_ptrcheck
1158 #define __header_indexable                  __indexable
1159 #define __header_bidi_indexable             __bidi_indexable
1160 #else
1161 #define __header_indexable
1162 #define __header_bidi_indexable
1163 #endif
1164 
1165 /*
1166  * Architecture validation for current SDK
1167  */
1168 #if !defined(__sys_cdefs_arch_unknown__) && defined(__i386__)
1169 #elif !defined(__sys_cdefs_arch_unknown__) && defined(__x86_64__)
1170 #elif !defined(__sys_cdefs_arch_unknown__) && defined(__arm__)
1171 #elif !defined(__sys_cdefs_arch_unknown__) && defined(__arm64__)
1172 #else
1173 #error Unsupported architecture
1174 #endif
1175 
1176 #ifdef XNU_KERNEL_PRIVATE
1177 /*
1178  * Selectively ignore cast alignment warnings
1179  */
1180 #define __IGNORE_WCASTALIGN(x) _Pragma("clang diagnostic push")                     \
1181 	                       _Pragma("clang diagnostic ignored \"-Wcast-align\"") \
1182 	                       x                                                    \
1183 	                       _Pragma("clang diagnostic pop")
1184 #endif
1185 
1186 #if defined(PRIVATE) || defined(KERNEL)
1187 /*
1188  * Check if __probable and __improbable have already been defined elsewhere.
1189  * These macros inform the compiler (and humans) about which branches are likely
1190  * to be taken.
1191  */
1192 #if !defined(__probable) && !defined(__improbable)
1193 #define __probable(x)   __builtin_expect(!!(x), 1)
1194 #define __improbable(x) __builtin_expect(!!(x), 0)
1195 #endif /* !defined(__probable) && !defined(__improbable) */
1196 
1197 #define __container_of(ptr, type_t, field) __extension__({ \
1198 	const __typeof__(((type_t *)NULL)->field) *__ptr = (ptr);               \
1199 	uintptr_t __result = (uintptr_t)__ptr - offsetof(type_t, field);        \
1200 	if (__ptr) __builtin_assume(__result != 0);                             \
1201 	__unsafe_forge_single(type_t *, __result);                              \
1202 })
1203 
1204 #define __container_of_safe(ptr, type_t, field) __extension__({ \
1205 	const __typeof__(((type_t *)NULL)->field) *__ptr_or_null = (ptr);       \
1206 	__ptr_or_null ? __container_of(__ptr_or_null, type_t, field) : NULL;    \
1207 })
1208 
1209 /*
1210  * This forces the optimizer to materialize the specified variable value,
1211  * and prevents any reordering of operations done to it.
1212  */
1213 #define __compiler_materialize_and_prevent_reordering_on(var) \
1214 	__asm__ ("" : "=r"(var) : "0"(var))
1215 
1216 #endif /* KERNEL || PRIVATE */
1217 
1218 #define __compiler_barrier() __asm__ __volatile__("" ::: "memory")
1219 
1220 #if __has_attribute(enum_extensibility)
1221 #define __enum_open __attribute__((__enum_extensibility__(open)))
1222 #define __enum_closed __attribute__((__enum_extensibility__(closed)))
1223 #else
1224 #define __enum_open
1225 #define __enum_closed
1226 #endif // __has_attribute(enum_extensibility)
1227 
1228 #if __has_attribute(flag_enum)
1229 #define __enum_options __attribute__((__flag_enum__))
1230 #else
1231 #define __enum_options
1232 #endif
1233 
1234 /*
1235  * Similar to OS_ENUM/OS_CLOSED_ENUM/OS_OPTIONS/OS_CLOSED_OPTIONS
1236  *
1237  * This provides more advanced type checking on compilers supporting
1238  * the proper extensions, even in C.
1239  */
1240 #if __has_feature(objc_fixed_enum) || __has_extension(cxx_fixed_enum) || \
1241         __has_extension(cxx_strong_enums)
1242 #define __enum_decl(_name, _type, ...) \
1243 	        typedef enum : _type __VA_ARGS__ __enum_open _name
1244 #define __enum_closed_decl(_name, _type, ...) \
1245 	        typedef enum : _type __VA_ARGS__ __enum_closed _name
1246 #define __options_decl(_name, _type, ...) \
1247 	        typedef enum : _type __VA_ARGS__ __enum_open __enum_options _name
1248 #define __options_closed_decl(_name, _type, ...) \
1249 	        typedef enum : _type __VA_ARGS__ __enum_closed __enum_options _name
1250 #else
1251 #define __enum_decl(_name, _type, ...) \
1252 	        typedef _type _name; enum __VA_ARGS__ __enum_open
1253 #define __enum_closed_decl(_name, _type, ...) \
1254 	        typedef _type _name; enum __VA_ARGS__ __enum_closed
1255 #define __options_decl(_name, _type, ...) \
1256 	        typedef _type _name; enum __VA_ARGS__ __enum_open __enum_options
1257 #define __options_closed_decl(_name, _type, ...) \
1258 	        typedef _type _name; enum __VA_ARGS__ __enum_closed __enum_options
1259 #endif
1260 
1261 #if XNU_KERNEL_PRIVATE
1262 /*
1263  * __xnu_struct_group() can be used to declare a set of fields to be grouped
1264  * together logically in order to perform safer memory operations
1265  * (assignment, zeroing, ...) on them.
1266  */
1267 #ifdef __cplusplus
1268 #define __xnu_struct_group(group_type, group_name, ...) \
1269 	struct group_type __VA_ARGS__; \
1270 	union { \
1271 	    struct __VA_ARGS__; \
1272 	    struct group_type group_name; \
1273 	}
1274 #else
1275 #define __xnu_struct_group(group_type, group_name, ...) \
1276 	union { \
1277 	    struct __VA_ARGS__; \
1278 	    struct group_type __VA_ARGS__ group_name; \
1279 	}
1280 #endif
1281 #endif /* XNU_KERNEL_PRIVATE */
1282 
1283 #if defined(KERNEL) && __has_attribute(xnu_usage_semantics)
1284 /*
1285  * These macros can be used to annotate type definitions or scalar structure
1286  * fields to inform the compiler about which semantic they have with regards
1287  * to the content of the underlying memory represented by such type or field.
1288  *
1289  * This information is used in the analysis of the types performed by the
1290  * signature based type segregation implemented in kalloc.
1291  */
1292 #define __kernel_ptr_semantics __attribute__((xnu_usage_semantics("pointer")))
1293 #define __kernel_data_semantics __attribute__((xnu_usage_semantics("data")))
1294 #define __kernel_dual_semantics __attribute__((xnu_usage_semantics("pointer", "data")))
1295 
1296 #else  /* defined(KERNEL) && __has_attribute(xnu_usage_semantics) */
1297 
1298 #define __kernel_ptr_semantics
1299 #define __kernel_data_semantics
1300 #define __kernel_dual_semantics
1301 
1302 #endif /* defined(KERNEL) && __has_attribute(xnu_usage_semantics) */
1303 
1304 #if XNU_KERNEL_PRIVATE
1305 /*
1306  * Compiler-dependent macros that bracket portions of code where the
1307  * "-Wxnu-typed-allocators" warning should be ignored.
1308  */
1309 #if defined(__clang__)
1310 # define __typed_allocators_ignore_push \
1311 	 _Pragma("clang diagnostic push") \
1312 	 _Pragma("clang diagnostic ignored \"-Wxnu-typed-allocators\"")
1313 # define __typed_allocators_ignore_pop \
1314 	 _Pragma("clang diagnostic pop")
1315 # define __typed_allocators_ignore(x) __typed_allocators_ignore_push \
1316 	                              x                              \
1317 	                              __typed_allocators_ignore_pop
1318 #else
1319 # define __typed_allocators_ignore_push
1320 # define __typed_allocators_ignore_push
1321 # define __typed_allocators_ignore(x) x
1322 #endif /* __clang */
1323 #endif /* XNU_KERNEL_PRIVATE */
1324 
1325 #endif /* !_CDEFS_H_ */
1326