/*
 * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright 1995 NeXT Computer, Inc. All rights reserved. */
/*
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Berkeley Software Design, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)cdefs.h	8.8 (Berkeley) 1/9/95
 */

#ifndef _CDEFS_H_
#define _CDEFS_H_

#if defined(__cplusplus)
#define __BEGIN_DECLS   extern "C" {
#define __END_DECLS     }
#else
#define __BEGIN_DECLS
#define __END_DECLS
#endif

/* This SDK is designed to work with clang and specific versions of
 * gcc >= 4.0 with Apple's patch sets */
#if !defined(__GNUC__) || __GNUC__ < 4
#warning "Unsupported compiler detected"
#endif

/*
 * Compatibility with compilers and environments that don't support compiler
 * feature checking function-like macros.
 */
#ifndef __has_builtin
#define __has_builtin(x) 0
#endif
#ifndef __has_include
#define __has_include(x) 0
#endif
#ifndef __has_feature
#define __has_feature(x) 0
#endif
#ifndef __has_attribute
#define __has_attribute(x) 0
#endif
#ifndef __has_cpp_attribute
#define __has_cpp_attribute(x) 0
#endif
#ifndef __has_extension
#define __has_extension(x) 0
#endif

/*
 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
 * The __CONCAT macro is a bit tricky -- make sure you don't put spaces
 * in between its arguments.  __CONCAT can also concatenate double-quoted
 * strings produced by the __STRING macro, but this only works with ANSI C.
 */
#if defined(__STDC__) || defined(__cplusplus)
#define __P(protos)     protos          /* full-blown ANSI C */
#define __CONCAT(x, y)   x ## y
#define __STRING(x)     #x

#define __const         const           /* define reserved names to standard */
#define __signed        signed
#define __volatile      volatile
#if defined(__cplusplus)
#define __inline        inline          /* convert to C++ keyword */
#else
#ifndef __GNUC__
#define __inline                        /* delete GCC keyword */
#endif /* !__GNUC__ */
#endif /* !__cplusplus */

#else   /* !(__STDC__ || __cplusplus) */
#define __P(protos)     ()              /* traditional C preprocessor */
#define __CONCAT(x, y)   x /**/ y
#define __STRING(x)     "x"

#ifndef __GNUC__
#define __const                         /* delete pseudo-ANSI C keywords */
#define __inline
#define __signed
#define __volatile
#endif  /* !__GNUC__ */

/*
 * In non-ANSI C environments, new programs will want ANSI-only C keywords
 * deleted from the program and old programs will want them left alone.
 * When using a compiler other than gcc, programs using the ANSI C keywords
 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
 * When using "gcc -traditional", we assume that this is the intent; if
 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
 */
#ifndef NO_ANSI_KEYWORDS
#define const           __const                 /* convert ANSI C keywords */
#define inline          __inline
#define signed          __signed
#define volatile        __volatile
#endif /* !NO_ANSI_KEYWORDS */
#endif /* !(__STDC__ || __cplusplus) */

/*
 * __pure2 can be used for functions that are only a function of their scalar
 * arguments (meaning they can't dereference pointers).
 *
 * __stateful_pure can be used for functions that have no side effects,
 * but depend on the state of the memory.
 */
#define __dead2         __attribute__((__noreturn__))
#define __pure2         __attribute__((__const__))
#define __stateful_pure __attribute__((__pure__))

/* __unused denotes variables and functions that may not be used, preventing
 * the compiler from warning about it if not used.
 */
#define __unused        __attribute__((__unused__))

/* __used forces variables and functions to be included even if it appears
 * to the compiler that they are not used (and would thust be discarded).
 */
#define __used          __attribute__((__used__))

/* __cold marks code used for debugging or that is rarely taken
 * and tells the compiler to optimize for size and outline code.
 */
#if __has_attribute(cold)
#define __cold          __attribute__((__cold__))
#else
#define __cold
#endif

/* __returns_nonnull marks functions that return a non-null pointer. */
#if __has_attribute(returns_nonnull)
#define __returns_nonnull __attribute((returns_nonnull))
#else
#define __returns_nonnull
#endif

/* __exported denotes symbols that should be exported even when symbols
 * are hidden by default.
 * __exported_push/_exported_pop are pragmas used to delimit a range of
 *  symbols that should be exported even when symbols are hidden by default.
 */
#define __exported      __attribute__((__visibility__("default")))
#define __exported_push _Pragma("GCC visibility push(default)")
#ifndef __BUILDING_XNU_LIBRARY__
#define __exported_push_hidden _Pragma("GCC visibility push(hidden)")
#define __exported_pop  _Pragma("GCC visibility pop")
#define __exported_hidden __private_extern__
#else /* __BUILDING_XNU_LIBRARY__ */
/* Don't hide symbols that the might be need to be used from outside */
#define __exported_push_hidden
#define __exported_pop
#define __exported_hidden
#endif /* __BUILDING_XNU_LIBRARY__ */

/* __deprecated causes the compiler to produce a warning when encountering
 * code using the deprecated functionality.
 * __deprecated_msg() does the same, and compilers that support it will print
 * a message along with the deprecation warning.
 * This may require turning on such warning with the -Wdeprecated flag.
 * __deprecated_enum_msg() should be used on enums, and compilers that support
 * it will print the deprecation warning.
 * __kpi_deprecated() specifically indicates deprecation of kernel programming
 * interfaces in Kernel.framework used by KEXTs.
 */
#define __deprecated    __attribute__((__deprecated__))

#if __has_extension(attribute_deprecated_with_message) || \
        (defined(__GNUC__) && ((__GNUC__ >= 5) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5))))
	#define __deprecated_msg(_msg) __attribute__((__deprecated__(_msg)))
#else
	#define __deprecated_msg(_msg) __attribute__((__deprecated__))
#endif

#if __has_extension(enumerator_attributes)
	#define __deprecated_enum_msg(_msg) __deprecated_msg(_msg)
#else
	#define __deprecated_enum_msg(_msg)
#endif

#if defined(KERNEL) && !defined(KERNEL_PRIVATE)
#define __kpi_deprecated(_msg) __deprecated_msg(_msg)
#else /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
#define __kpi_deprecated(_msg)
#endif /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */

/* __unavailable causes the compiler to error out when encountering
 * code using the tagged function
 */
#if __has_attribute(unavailable)
#define __unavailable __attribute__((__unavailable__))
#else
#define __unavailable
#endif

#if defined(KERNEL) && !defined(KERNEL_PRIVATE)
#define __kpi_unavailable __unavailable
#else /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */
#define __kpi_unavailable
#endif /* !defined(KERNEL) || defined(KERNEL_PRIVATE) */

#if XNU_KERNEL_PRIVATE
/* This macro is meant to be used for kpi deprecated to x86 3rd parties
 * but should be marked as unavailable for arm macOS devices.
 * XNU:                         nothing (API is still available)
 * 1st party kexts:             __deprecated
 * 3rd party kexts macOS x86:   __deprecated
 * 3rd party kexts macOS arm:   __unavailable
 */
#define __kpi_deprecated_arm64_macos_unavailable
#elif !KERNEL || !XNU_PLATFORM_MacOSX
#define __kpi_deprecated_arm64_macos_unavailable
#elif KERNEL_PRIVATE
#define __kpi_deprecated_arm64_macos_unavailable __deprecated
#elif defined(__arm64__)
#define __kpi_deprecated_arm64_macos_unavailable __unavailable
#else
#define __kpi_deprecated_arm64_macos_unavailable __deprecated
#endif /* XNU_KERNEL_PRIVATE */

/* Delete pseudo-keywords wherever they are not available or needed. */
#ifndef __dead
#define __dead
#define __pure
#endif

/*
 * We use `__restrict' as a way to define the `restrict' type qualifier
 * without disturbing older software that is unaware of C99 keywords.
 */
#if __STDC_VERSION__ < 199901
#define __restrict
#else
#define __restrict      restrict
#endif

/* Compatibility with compilers and environments that don't support the
 * nullability feature.
 */

#if !__has_feature(nullability)
#ifndef __nullable
#define __nullable
#endif
#ifndef __nonnull
#define __nonnull
#endif
#ifndef __null_unspecified
#define __null_unspecified
#endif
#ifndef _Nullable
#define _Nullable
#endif
#ifndef _Nonnull
#define _Nonnull
#endif
#ifndef _Null_unspecified
#define _Null_unspecified
#endif
#endif

/*
 * __disable_tail_calls causes the compiler to not perform tail call
 * optimization inside the marked function.
 */
#if __has_attribute(disable_tail_calls)
#define __disable_tail_calls    __attribute__((__disable_tail_calls__))
#else
#define __disable_tail_calls
#endif

/*
 * __not_tail_called causes the compiler to prevent tail call optimization
 * on statically bound calls to the function.  It has no effect on indirect
 * calls.  Virtual functions, objective-c methods, and functions marked as
 * "always_inline" cannot be marked as __not_tail_called.
 */
#if __has_attribute(not_tail_called)
#define __not_tail_called       __attribute__((__not_tail_called__))
#else
#define __not_tail_called
#endif

/*
 * __result_use_check warns callers of a function that not using the function
 * return value is a bug, i.e. dismissing malloc() return value results in a
 * memory leak.
 */
#if __has_attribute(warn_unused_result)
#define __result_use_check __attribute__((__warn_unused_result__))
#else
#define __result_use_check
#endif

/*
 * __swift_unavailable causes the compiler to mark a symbol as specifically
 * unavailable in Swift, regardless of any other availability in C.
 */
#if __has_feature(attribute_availability_swift)
#define __swift_unavailable(_msg)       __attribute__((__availability__(swift, unavailable, message=_msg)))
#else
#define __swift_unavailable(_msg)
#endif

/*
 * Attributes to support Swift concurrency.
 */
#if __has_attribute(__swift_attr__)
#define __swift_unavailable_from_async(_msg)    __attribute__((__swift_attr__("@_unavailableFromAsync(message: \"" _msg "\")")))
#define __swift_nonisolated                     __attribute__((__swift_attr__("nonisolated")))
#define __swift_nonisolated_unsafe              __attribute__((__swift_attr__("nonisolated(unsafe)")))
#else
#define __swift_unavailable_from_async(_msg)
#define __swift_nonisolated
#define __swift_nonisolated_unsafe
#endif

/*
 * __abortlike is the attribute to put on functions like abort() that are
 * typically used to mark assertions. These optimize the codegen
 * for outlining while still maintaining debugability.
 */
#ifndef __abortlike
#define __abortlike __dead2 __cold __not_tail_called
#endif

/* Declaring inline functions within headers is error-prone due to differences
 * across various versions of the C language and extensions.  __header_inline
 * can be used to declare inline functions within system headers.  In cases
 * where you want to force inlining instead of letting the compiler make
 * the decision, you can use __header_always_inline.
 *
 * Be aware that using inline for functions which compilers may also provide
 * builtins can behave differently under various compilers.  If you intend to
 * provide an inline version of such a function, you may want to use a macro
 * instead.
 *
 * The check for !__GNUC__ || __clang__ is because gcc doesn't correctly
 * support c99 inline in some cases:
 * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55965
 */

#if defined(__cplusplus) || \
        (__STDC_VERSION__ >= 199901L && \
        !defined(__GNUC_GNU_INLINE__) && \
        (!defined(__GNUC__) || defined(__clang__)))
# define __header_inline           inline
#elif defined(__GNUC__) && defined(__GNUC_STDC_INLINE__)
# define __header_inline           extern __inline __attribute__((__gnu_inline__))
#elif defined(__GNUC__)
# define __header_inline           extern __inline
#else
/* If we land here, we've encountered an unsupported compiler,
 * so hopefully it understands static __inline as a fallback.
 */
# define __header_inline           static __inline
#endif

#ifdef __GNUC__
# define __header_always_inline    __header_inline __attribute__ ((__always_inline__))
#else
/* Unfortunately, we're using a compiler that we don't know how to force to
 * inline.  Oh well.
 */
# define __header_always_inline    __header_inline
#endif

/*
 * Compiler-dependent macros that bracket portions of code where the
 * "-Wunreachable-code" warning should be ignored. Please use sparingly.
 */
#if defined(__clang__)
# define __unreachable_ok_push \
	 _Pragma("clang diagnostic push") \
	 _Pragma("clang diagnostic ignored \"-Wunreachable-code\"")
# define __unreachable_ok_pop \
	 _Pragma("clang diagnostic pop")
#elif defined(__GNUC__) && ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
# define __unreachable_ok_push \
	 _Pragma("GCC diagnostic push") \
	 _Pragma("GCC diagnostic ignored \"-Wunreachable-code\"")
# define __unreachable_ok_pop \
	 _Pragma("GCC diagnostic pop")
#else
# define __unreachable_ok_push
# define __unreachable_ok_pop
#endif

/*
 * Compiler-dependent macros to declare that functions take printf-like
 * or scanf-like arguments.  They are null except for versions of gcc
 * that are known to support the features properly.  Functions declared
 * with these attributes will cause compilation warnings if there is a
 * mismatch between the format string and subsequent function parameter
 * types.
 */
#define __printflike(fmtarg, firstvararg) \
	__attribute__((__format__ (__printf__, fmtarg, firstvararg)))
#define __printf0like(fmtarg, firstvararg) \
	__attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
#define __scanflike(fmtarg, firstvararg) \
	__attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
#define __osloglike(fmtarg, firstvararg) \
	__attribute__((__format__ (__os_log__, fmtarg, firstvararg)))

#define __IDSTRING(name, string) static const char name[] __used = string

#ifndef __COPYRIGHT
#define __COPYRIGHT(s) __IDSTRING(copyright,s)
#endif

#ifndef __RCSID
#define __RCSID(s) __IDSTRING(rcsid,s)
#endif

#ifndef __SCCSID
#define __SCCSID(s) __IDSTRING(sccsid,s)
#endif

#ifndef __PROJECT_VERSION
#define __PROJECT_VERSION(s) __IDSTRING(project_version,s)
#endif

/* Source compatibility only, ID string not emitted in object file */
#ifndef __FBSDID
#define __FBSDID(s)
#endif

#ifndef __DECONST
#define __DECONST(type, var)    __CAST_AWAY_QUALIFIER(var, const, type)
#endif

#ifndef __DEVOLATILE
#define __DEVOLATILE(type, var) __CAST_AWAY_QUALIFIER(var, volatile, type)
#endif

#ifndef __DEQUALIFY
#define __DEQUALIFY(type, var)  __CAST_AWAY_QUALIFIER(var, const volatile, type)
#endif

/*
 * __alloc_align can be used to label function arguments that represent the
 * alignment of the returned pointer.
 */
#ifndef __alloc_align
#if __has_attribute(alloc_align)
#define __alloc_align(n) __attribute__((alloc_align(n)))
#else
#define __alloc_align(n)
#endif
#endif // __alloc_align

/*
 * __alloc_size can be used to label function arguments that represent the
 * size of memory that the function allocates and returns. The one-argument
 * form labels a single argument that gives the allocation size (where the
 * arguments are numbered from 1):
 *
 * void	*malloc(size_t __size) __alloc_size(1);
 *
 * The two-argument form handles the case where the size is calculated as the
 * product of two arguments:
 *
 * void	*calloc(size_t __count, size_t __size) __alloc_size(1,2);
 */
#ifndef __alloc_size
#if __has_attribute(alloc_size)
#define __alloc_size(...) __attribute__((alloc_size(__VA_ARGS__)))
#else
#define __alloc_size(...)
#endif
#endif // __alloc_size

/*
 * Facilities below assist adoption of -Wunsafe-buffer-usage, an off-by-default
 * Clang compiler warning that helps the developer minimize unsafe, raw
 * buffer manipulation in the code that may lead to buffer overflow
 * vulnerabilities.
 *
 * They are primarily designed for modern C++ code where -Wunsafe-buffer-usage
 * comes with automatic fix-it hints that help the developer transform
 * their code to use modern C++ containers, which may be made bounds-safe by
 * linking against a version of the C++ standard library that offers
 * bounds-checked containers.
 * They can be used in plain C, but -fbounds-safety is the preferred solution
 * for plain C (see also <ptrcheck.h>).
 *
 * Attribute __unsafe_buffer_usage can be used to label functions that should be
 * avoided as they may perform or otherwise introduce unsafe buffer manipulation
 * operations. The attribute can also be attached to class/struct fields that
 * are used in unsafe buffer manipulations.
 *
 * Calls to attribute annotated functions are flagged by -Wunsafe-buffer-usage, similar to
 * how unchecked buffer manipulation operations are flagged when observed
 * by the compiler directly. Similarly, use of and assignment to the struct/class fields
 * that have the attribute also get flagged by the compiler.
 *
 *   // An unsafe function that needs to be avoided.
 *   __unsafe_buffer_usage
 *   void foo(int *buf, size_t size);
 *
 *   // A safe alternative to foo().
 *   void foo(std::span<int> buf);
 *
 *   void bar(size_t idx) {
 *       int array[5];
 *
 *       // Direct unsafe buffer manipulation through subscript operator:
 *       array[idx] = 3;  // warning: function introduces unsafe buffer manipulation [-Wunsafe-buffer-usage]
 *       // Unsafe buffer manipulation through function foo():
 *       foo(array, 5);   // warning: function introduces unsafe buffer manipulation [-Wunsafe-buffer-usage]
 *       // Checked buffer manipulation, with bounds information automatically
 *       // preserved for the purposes of runtime checks in standard library:
 *       foo(array);      // no warning
 *   }
 *
 *   struct Reader {
 *      // Field involved in unsafe buffer manipulation
 *      __unsafe_buffer_usage
 *      void *ptr;
 *
 *      __unsafe_buffer_usage
 *      size_t sz, count;
 *   };
 *
 *   void add_element(Reader rdr, int value) {
 *      if(rdr.count < rdr.sz) { // warning: unsafe buffer access [-Wunsafe-buffer-usage]
 *         rdr.ptr[rdr.count] = value; // warning: unsafe buffer access [-Wunsafe-buffer-usage]
 *         rdr.count++; // warning: unsafe buffer access [-Wunsafe-buffer-usage]
 *      }
 *   }
 *
 * While annotating a function as __unsafe_buffer_usage has an effect similar
 * to annotating it as __deprecated, the __unsafe_buffer_usage attribute
 * should be used whenever the resulting warning needs to be controlled
 * by the -Wunsafe-buffer-usage flag (which is turned off in codebases that
 * don't attempt to achieve bounds safety this way) as opposed to -Wdeprecated
 * (enabled in most codebases).
 *
 * The attribute suppresses all -Wunsafe-buffer-usage warnings inside the
 * function's body as it is explictly marked as unsafe by the user and
 * introduces new warnings at each call site to help the developers avoid the
 * function entirely. Most of the time it does not make sense to annotate a
 * function as __unsafe_buffer_usage without providing the users with a safe
 * alternative.
 *
 * Pragmas __unsafe_buffer_usage_begin and __unsafe_buffer_usage_end
 * annotate a range of code as intentionally containing unsafe buffer
 * operations. They suppress -Wunsafe-buffer-usage warnings
 * for unsafe operations in range:
 *
 *   __unsafe_buffer_usage_begin
 *   array[idx] = 3; // warning suppressed
 *   foo(array, 5);  // warning suppressed
 *   __unsafe_buffer_usage_end
 *
 * These pragmas are NOT a way to mass-annotate functions with the attribute
 * __unsafe_buffer_usage. Functions declared within the pragma range
 * do NOT get annotated automatically.
 */
#if __has_cpp_attribute(clang::unsafe_buffer_usage)
#define __has_safe_buffers 1
#define __unsafe_buffer_usage [[clang::unsafe_buffer_usage]]
#elif __has_attribute(unsafe_buffer_usage)
#define __has_safe_buffers 1
#define __unsafe_buffer_usage __attribute__((__unsafe_buffer_usage__))
#else
#define __has_safe_buffers 0
#define __unsafe_buffer_usage
#endif
#if __has_safe_buffers
#define __unsafe_buffer_usage_begin _Pragma("clang unsafe_buffer_usage begin")
#define __unsafe_buffer_usage_end   _Pragma("clang unsafe_buffer_usage end")
#else
#define __unsafe_buffer_usage_begin
#define __unsafe_buffer_usage_end
#endif

/*
 * COMPILATION ENVIRONMENTS -- see compat(5) for additional detail
 *
 * DEFAULT	By default newly complied code will get POSIX APIs plus
 *		Apple API extensions in scope.
 *
 *		Most users will use this compilation environment to avoid
 *		behavioral differences between 32 and 64 bit code.
 *
 * LEGACY	Defining _NONSTD_SOURCE will get pre-POSIX APIs plus Apple
 *		API extensions in scope.
 *
 *		This is generally equivalent to the Tiger release compilation
 *		environment, except that it cannot be applied to 64 bit code;
 *		its use is discouraged.
 *
 *		We expect this environment to be deprecated in the future.
 *
 * STRICT	Defining _POSIX_C_SOURCE or _XOPEN_SOURCE restricts the
 *		available APIs to exactly the set of APIs defined by the
 *		corresponding standard, based on the value defined.
 *
 *		A correct, portable definition for _POSIX_C_SOURCE is 200112L.
 *		A correct, portable definition for _XOPEN_SOURCE is 600L.
 *
 *		Apple API extensions are not visible in this environment,
 *		which can cause Apple specific code to fail to compile,
 *		or behave incorrectly if prototypes are not in scope or
 *		warnings about missing prototypes are not enabled or ignored.
 *
 * In any compilation environment, for correct symbol resolution to occur,
 * function prototypes must be in scope.  It is recommended that all Apple
 * tools users add either the "-Wall" or "-Wimplicit-function-declaration"
 * compiler flags to their projects to be warned when a function is being
 * used without a prototype in scope.
 */

/* These settings are particular to each product. */
#ifdef KERNEL
#define __DARWIN_ONLY_64_BIT_INO_T      0
#define __DARWIN_ONLY_UNIX_CONFORMANCE  0
#define __DARWIN_ONLY_VERS_1050         0
#if defined(__x86_64__)
#define __DARWIN_SUF_DARWIN14   "_darwin14"
#define __DARWIN14_ALIAS(sym)   __asm("_" __STRING(sym) __DARWIN_SUF_DARWIN14)
#else
#define __DARWIN14_ALIAS(sym)
#endif
#else /* !KERNEL */
#ifdef XNU_PLATFORM_iPhoneOS
/* Platform: iPhoneOS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_iPhoneOS */
#ifdef XNU_PLATFORM_iPhoneSimulator
/* Platform: iPhoneSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_iPhoneSimulator */
#ifdef XNU_PLATFORM_tvOS
/* Platform: tvOS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_tvOS */
#ifdef XNU_PLATFORM_AppleTVOS
/* Platform: AppleTVOS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_AppleTVOS */
#ifdef XNU_PLATFORM_tvSimulator
/* Platform: tvSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_tvSimulator */
#ifdef XNU_PLATFORM_AppleTVSimulator
/* Platform: AppleTVSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_AppleTVSimulator */
#ifdef XNU_PLATFORM_iPhoneOSNano
/* Platform: iPhoneOSNano */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_iPhoneOSNano */
#ifdef XNU_PLATFORM_iPhoneNanoSimulator
/* Platform: iPhoneNanoSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_iPhoneNanoSimulator */
#ifdef XNU_PLATFORM_WatchOS
/* Platform: WatchOS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_WatchOS */
#ifdef XNU_PLATFORM_WatchSimulator
/* Platform: WatchSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_WatchSimulator */
#ifdef XNU_PLATFORM_BridgeOS
/* Platform: BridgeOS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_BridgeOS */
#ifdef XNU_PLATFORM_DriverKit
/* Platform: DriverKit */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_DriverKit */
#ifdef XNU_PLATFORM_MacOSX
/* Platform: MacOSX */
#if defined(__i386__)
#define __DARWIN_ONLY_64_BIT_INO_T      0
#define __DARWIN_ONLY_UNIX_CONFORMANCE  0
#define __DARWIN_ONLY_VERS_1050         0
#elif defined(__x86_64__)
#define __DARWIN_ONLY_64_BIT_INO_T      0
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         0
#else
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif
#endif /* XNU_PLATFORM_MacOSX */
#ifdef XNU_PLATFORM_XROS
/* Platform: XROS */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_XROS */
#ifdef XNU_PLATFORM_XRSimulator
/* Platform: XRSimulator */
#define __DARWIN_ONLY_64_BIT_INO_T      1
#define __DARWIN_ONLY_UNIX_CONFORMANCE  1
#define __DARWIN_ONLY_VERS_1050         1
#endif /* XNU_PLATFORM_XRSimulator */
#endif /* KERNEL */

/*
 * The __DARWIN_ALIAS macros are used to do symbol renaming; they allow
 * legacy code to use the old symbol, thus maintaining binary compatibility
 * while new code can use a standards compliant version of the same function.
 *
 * __DARWIN_ALIAS is used by itself if the function signature has not
 * changed, it is used along with a #ifdef check for __DARWIN_UNIX03
 * if the signature has changed.  Because the __LP64__ environment
 * only supports UNIX03 semantics it causes __DARWIN_UNIX03 to be
 * defined, but causes __DARWIN_ALIAS to do no symbol mangling.
 *
 * As a special case, when XCode is used to target a specific version of the
 * OS, the manifest constant __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__
 * will be defined by the compiler, with the digits representing major version
 * time 100 + minor version times 10 (e.g. 10.5 := 1050).  If we are targeting
 * pre-10.5, and it is the default compilation environment, revert the
 * compilation environment to pre-__DARWIN_UNIX03.
 */
#if !defined(__DARWIN_UNIX03)
#  if defined(KERNEL)
#    define __DARWIN_UNIX03     0
#  elif __DARWIN_ONLY_UNIX_CONFORMANCE
#    if defined(_NONSTD_SOURCE)
#      error "Can't define _NONSTD_SOURCE when only UNIX conformance is available."
#    endif /* _NONSTD_SOURCE */
#    define __DARWIN_UNIX03     1
#  elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1040)
#    define __DARWIN_UNIX03     0
#  elif defined(_DARWIN_C_SOURCE) || defined(_XOPEN_SOURCE) || defined(_POSIX_C_SOURCE)
#    if defined(_NONSTD_SOURCE)
#      error "Can't define both _NONSTD_SOURCE and any of _DARWIN_C_SOURCE, _XOPEN_SOURCE or _POSIX_C_SOURCE."
#    endif /* _NONSTD_SOURCE */
#    define __DARWIN_UNIX03     1
#  elif defined(_NONSTD_SOURCE)
#    define __DARWIN_UNIX03     0
#  else /* default */
#    if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1050)
#      define __DARWIN_UNIX03   0
#    else /* __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1050 */
#      define __DARWIN_UNIX03   1
#    endif /* __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1050 */
#  endif /* _DARWIN_C_SOURCE || _XOPEN_SOURCE || _POSIX_C_SOURCE || __LP64__ */
#endif /* !__DARWIN_UNIX03 */

#if !defined(__DARWIN_64_BIT_INO_T)
#  if defined(KERNEL)
#    define __DARWIN_64_BIT_INO_T 0
#  elif defined(_DARWIN_USE_64_BIT_INODE)
#    if defined(_DARWIN_NO_64_BIT_INODE)
#      error "Can't define both _DARWIN_USE_64_BIT_INODE and _DARWIN_NO_64_BIT_INODE."
#    endif /* _DARWIN_NO_64_BIT_INODE */
#    define __DARWIN_64_BIT_INO_T 1
#  elif defined(_DARWIN_NO_64_BIT_INODE)
#    if __DARWIN_ONLY_64_BIT_INO_T
#      error "Can't define _DARWIN_NO_64_BIT_INODE when only 64-bit inodes are available."
#    endif /* __DARWIN_ONLY_64_BIT_INO_T */
#    define __DARWIN_64_BIT_INO_T 0
#  else /* default */
#    if __DARWIN_ONLY_64_BIT_INO_T
#      define __DARWIN_64_BIT_INO_T 1
#    elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1060) || __DARWIN_UNIX03 == 0
#      define __DARWIN_64_BIT_INO_T 0
#    else /* default */
#      define __DARWIN_64_BIT_INO_T 1
#    endif /* __DARWIN_ONLY_64_BIT_INO_T */
#  endif
#endif /* !__DARWIN_64_BIT_INO_T */

#if !defined(__DARWIN_VERS_1050)
#  if defined(KERNEL)
#    define __DARWIN_VERS_1050 0
#  elif __DARWIN_ONLY_VERS_1050
#    define __DARWIN_VERS_1050 1
#  elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && ((__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ - 0) < 1050) || __DARWIN_UNIX03 == 0
#    define __DARWIN_VERS_1050 0
#  else /* default */
#    define __DARWIN_VERS_1050 1
#  endif
#endif /* !__DARWIN_VERS_1050 */

#if !defined(__DARWIN_NON_CANCELABLE)
#  if defined(KERNEL)
#    define __DARWIN_NON_CANCELABLE 0
#  else /* default */
#    define __DARWIN_NON_CANCELABLE 0
#  endif
#endif /* !__DARWIN_NON_CANCELABLE */

/*
 * symbol suffixes used for symbol versioning
 */
#if __DARWIN_UNIX03
#  if __DARWIN_ONLY_UNIX_CONFORMANCE
#    define __DARWIN_SUF_UNIX03         /* nothing */
#  else /* !__DARWIN_ONLY_UNIX_CONFORMANCE */
#    define __DARWIN_SUF_UNIX03         "$UNIX2003"
#  endif /* __DARWIN_ONLY_UNIX_CONFORMANCE */

#  if __DARWIN_64_BIT_INO_T
#    if __DARWIN_ONLY_64_BIT_INO_T
#      define __DARWIN_SUF_64_BIT_INO_T /* nothing */
#    else /* !__DARWIN_ONLY_64_BIT_INO_T */
#      define __DARWIN_SUF_64_BIT_INO_T "$INODE64"
#    endif /* __DARWIN_ONLY_64_BIT_INO_T */
#  else /* !__DARWIN_64_BIT_INO_T */
#    define __DARWIN_SUF_64_BIT_INO_T   /* nothing */
#  endif /* __DARWIN_64_BIT_INO_T */

#  if __DARWIN_VERS_1050
#    if __DARWIN_ONLY_VERS_1050
#      define __DARWIN_SUF_1050         /* nothing */
#    else /* !__DARWIN_ONLY_VERS_1050 */
#      define __DARWIN_SUF_1050         "$1050"
#    endif /* __DARWIN_ONLY_VERS_1050 */
#  else /* !__DARWIN_VERS_1050 */
#    define __DARWIN_SUF_1050           /* nothing */
#  endif /* __DARWIN_VERS_1050 */

#  if __DARWIN_NON_CANCELABLE
#    define __DARWIN_SUF_NON_CANCELABLE "$NOCANCEL"
#  else /* !__DARWIN_NON_CANCELABLE */
#    define __DARWIN_SUF_NON_CANCELABLE /* nothing */
#  endif /* __DARWIN_NON_CANCELABLE */

#else /* !__DARWIN_UNIX03 */
#  define __DARWIN_SUF_UNIX03           /* nothing */
#  define __DARWIN_SUF_64_BIT_INO_T     /* nothing */
#  define __DARWIN_SUF_NON_CANCELABLE   /* nothing */
#  define __DARWIN_SUF_1050             /* nothing */
#endif /* __DARWIN_UNIX03 */

#define __DARWIN_SUF_EXTSN              "$DARWIN_EXTSN"

/*
 * symbol versioning macros
 */
#define __DARWIN_ALIAS(sym)             __asm("_" __STRING(sym) __DARWIN_SUF_UNIX03)
#define __DARWIN_ALIAS_C(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_NON_CANCELABLE __DARWIN_SUF_UNIX03)
#define __DARWIN_ALIAS_I(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_64_BIT_INO_T __DARWIN_SUF_UNIX03)
#define __DARWIN_NOCANCEL(sym)          __asm("_" __STRING(sym) __DARWIN_SUF_NON_CANCELABLE)
#define __DARWIN_INODE64(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_64_BIT_INO_T)

#define __DARWIN_1050(sym)              __asm("_" __STRING(sym) __DARWIN_SUF_1050)
#define __DARWIN_1050ALIAS(sym)         __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_UNIX03)
#define __DARWIN_1050ALIAS_C(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_NON_CANCELABLE __DARWIN_SUF_UNIX03)
#define __DARWIN_1050ALIAS_I(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_64_BIT_INO_T __DARWIN_SUF_UNIX03)
#define __DARWIN_1050INODE64(sym)       __asm("_" __STRING(sym) __DARWIN_SUF_1050 __DARWIN_SUF_64_BIT_INO_T)

#define __DARWIN_EXTSN(sym)             __asm("_" __STRING(sym) __DARWIN_SUF_EXTSN)
#define __DARWIN_EXTSN_C(sym)           __asm("_" __STRING(sym) __DARWIN_SUF_EXTSN __DARWIN_SUF_NON_CANCELABLE)
#if XNU_KERNEL_PRIVATE
#define __XNU_INTERNAL(sym)             __asm("_" __STRING(sym) "$XNU_INTERNAL") __attribute__((used))
#endif

/*
 * symbol release macros
 */
#ifdef KERNEL
#define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)
#else
#include <sys/_symbol_aliasing.h>

#if defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
#define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   __DARWIN_ALIAS_STARTING_IPHONE_##_iphone(x)
#elif defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
#define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   __DARWIN_ALIAS_STARTING_MAC_##_mac(x)
#else
#define __DARWIN_ALIAS_STARTING(_mac, _iphone, x)   x
#endif
#endif /* KERNEL */


/*
 * POSIX.1 requires that the macros we test be defined before any standard
 * header file is included.  This permits us to convert values for feature
 * testing, as necessary, using only _POSIX_C_SOURCE.
 *
 * Here's a quick run-down of the versions:
 *  defined(_POSIX_SOURCE)		1003.1-1988
 *  _POSIX_C_SOURCE == 1L		1003.1-1990
 *  _POSIX_C_SOURCE == 2L		1003.2-1992 C Language Binding Option
 *  _POSIX_C_SOURCE == 199309L		1003.1b-1993
 *  _POSIX_C_SOURCE == 199506L		1003.1c-1995, 1003.1i-1995,
 *					and the omnibus ISO/IEC 9945-1: 1996
 *  _POSIX_C_SOURCE == 200112L		1003.1-2001
 *  _POSIX_C_SOURCE == 200809L		1003.1-2008
 *
 * In addition, the X/Open Portability Guide, which is now the Single UNIX
 * Specification, defines a feature-test macro which indicates the version of
 * that specification, and which subsumes _POSIX_C_SOURCE.
 */

/* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1L. */
#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1L
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE         199009L
#endif

/* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2L. */
#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2L
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE         199209L
#endif

/* Deal with various X/Open Portability Guides and Single UNIX Spec. */
#ifdef _XOPEN_SOURCE
#if _XOPEN_SOURCE - 0L >= 700L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 200809L)
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE         200809L
#elif _XOPEN_SOURCE - 0L >= 600L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 200112L)
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE         200112L
#elif _XOPEN_SOURCE - 0L >= 500L && (!defined(_POSIX_C_SOURCE) || _POSIX_C_SOURCE - 0L < 199506L)
#undef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE         199506L
#endif
#endif

/*
 * Deal with all versions of POSIX.  The ordering relative to the tests above is
 * important.
 */
#if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
#define _POSIX_C_SOURCE         198808L
#endif

/* POSIX C deprecation macros */
#ifdef KERNEL
#define __POSIX_C_DEPRECATED(ver)
#else
#include <sys/_posix_availability.h>

#define __POSIX_C_DEPRECATED(ver) ___POSIX_C_DEPRECATED_STARTING_##ver
#endif

/*
 * Set a single macro which will always be defined and can be used to determine
 * the appropriate namespace.  For POSIX, these values will correspond to
 * _POSIX_C_SOURCE value.  Currently there are two additional levels corresponding
 * to ANSI (_ANSI_SOURCE) and Darwin extensions (_DARWIN_C_SOURCE)
 */
#define __DARWIN_C_ANSI         010000L
#define __DARWIN_C_FULL         900000L

#if   defined(_ANSI_SOURCE)
#define __DARWIN_C_LEVEL        __DARWIN_C_ANSI
#elif defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE) && !defined(_NONSTD_SOURCE)
#define __DARWIN_C_LEVEL        _POSIX_C_SOURCE
#else
#define __DARWIN_C_LEVEL        __DARWIN_C_FULL
#endif

/* If the developer has neither requested a strict language mode nor a version
 * of POSIX, turn on functionality provided by __STDC_WANT_LIB_EXT1__ as part
 * of __DARWIN_C_FULL.
 */
#if !defined(__STDC_WANT_LIB_EXT1__) && !defined(__STRICT_ANSI__) && __DARWIN_C_LEVEL >= __DARWIN_C_FULL
#define __STDC_WANT_LIB_EXT1__ 1
#endif

/*
 * long long is not supported in c89 (__STRICT_ANSI__), but g++ -ansi and
 * c99 still want long longs.  While not perfect, we allow long longs for
 * g++.
 */
#if (defined(__STRICT_ANSI__) && (__STDC_VERSION__ - 0 < 199901L) && !defined(__GNUG__))
#define __DARWIN_NO_LONG_LONG 1
#else
#define __DARWIN_NO_LONG_LONG 0
#endif

/*****************************************
*  Public darwin-specific feature macros
*****************************************/

/*
 * _DARWIN_FEATURE_64_BIT_INODE indicates that the ino_t type is 64-bit, and
 * structures modified for 64-bit inodes (like struct stat) will be used.
 */
#if __DARWIN_64_BIT_INO_T
#define _DARWIN_FEATURE_64_BIT_INODE            1
#endif

/*
 * _DARWIN_FEATURE_64_ONLY_BIT_INODE indicates that the ino_t type may only
 * be 64-bit; there is no support for 32-bit ino_t when this macro is defined
 * (and non-zero).  There is no struct stat64 either, as the regular
 * struct stat will already be the 64-bit version.
 */
#if __DARWIN_ONLY_64_BIT_INO_T
#define _DARWIN_FEATURE_ONLY_64_BIT_INODE       1
#endif

/*
 * _DARWIN_FEATURE_ONLY_VERS_1050 indicates that only those APIs updated
 * in 10.5 exists; no pre-10.5 variants are available.
 */
#if __DARWIN_ONLY_VERS_1050
#define _DARWIN_FEATURE_ONLY_VERS_1050          1
#endif

/*
 * _DARWIN_FEATURE_ONLY_UNIX_CONFORMANCE indicates only UNIX conforming API
 * are available (the legacy BSD APIs are not available)
 */
#if __DARWIN_ONLY_UNIX_CONFORMANCE
#define _DARWIN_FEATURE_ONLY_UNIX_CONFORMANCE   1
#endif

/*
 * _DARWIN_FEATURE_UNIX_CONFORMANCE indicates whether UNIX conformance is on,
 * and specifies the conformance level (3 is SUSv3)
 */
#if __DARWIN_UNIX03
#define _DARWIN_FEATURE_UNIX_CONFORMANCE        3
#endif

#if defined(DRIVERKIT) && !defined(KERNEL)
/*
 * __DRIVERKIT_LIBC__ indicates to the C++ standard library headers and
 * similar components that only the restricted set of standard C library
 * functionality and headers for the DriverKit userspace driver environment
 * are available.
 */
#define __DRIVERKIT_LIBC__                      1
#endif /* defined(DRIVERKIT) && !defined(KERNEL) */

/*
 * This macro casts away the qualifier from the variable
 *
 * Note: use at your own risk, removing qualifiers can result in
 * catastrophic run-time failures.
 */
#ifndef __CAST_AWAY_QUALIFIER
/*
 * XXX: this shouldn't ignore anything more than -Wcast-qual,
 * but the old implementation made it an almighty cast that
 * ignored everything, so things break left and right if you
 * make it only ignore -Wcast-qual.
 */
#define __CAST_AWAY_QUALIFIER(variable, qualifier, type) \
	_Pragma("GCC diagnostic push") \
	_Pragma("GCC diagnostic ignored \"-Wcast-qual\"") \
	_Pragma("GCC diagnostic ignored \"-Wcast-align\"") \
	_Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"") \
	((type)(variable)) \
	_Pragma("GCC diagnostic pop")
#endif

/*
 * __XNU_PRIVATE_EXTERN is a linkage decoration indicating that a symbol can be
 * used from other compilation units, but not other libraries or executables.
 */
#ifndef __XNU_PRIVATE_EXTERN
#define __XNU_PRIVATE_EXTERN __attribute__((visibility("hidden")))
#endif

#if __has_include(<ptrcheck.h>)
#include <ptrcheck.h>
#else
#if __has_feature(bounds_safety)
#error -fbounds-safety is enabled, but <ptrcheck.h> is missing. \
        This will lead to difficult-to-diagnose compilation errors.
#endif /* __has_feature(bounds_safety) */

/*
 * We intentionally define to nothing pointer attributes which do not have an
 * impact on the ABI. __indexable and __bidi_indexable are not defined because
 * of the ABI incompatibility that makes the diagnostic preferable.
 */
#define __has_ptrcheck 0
#define __single
#define __unsafe_indexable
#define __counted_by(N)
#define __counted_by_or_null(N)
#define __sized_by(N)
#define __sized_by_or_null(N)
#define __ended_by(E)
#define __terminated_by(T)
#define __null_terminated

/*
 * Similarly, we intentionally define to nothing the
 * __ptrcheck_abi_assume_single and __ptrcheck_abi_assume_unsafe_indexable
 * macros because they do not lead to an ABI incompatibility. However, we do not
 * define the indexable and unsafe_indexable ones because the diagnostic is
 * better than the silent ABI break.
 */
#define __ptrcheck_abi_assume_single()
#define __ptrcheck_abi_assume_unsafe_indexable()

/* __unsafe_forge intrinsics are defined as regular C casts. */
#define __unsafe_forge_bidi_indexable(T, P, S) ((T)(P))
#define __unsafe_forge_single(T, P) ((T)(P))
#define __unsafe_forge_terminated_by(T, P, E) ((T)(P))
#define __unsafe_forge_null_terminated(T, P) ((T)(P))
#define __terminated_by_to_indexable(P) (P)
#define __unsafe_terminated_by_to_indexable(P) (P)
#define __null_terminated_to_indexable(P) (P)
#define __unsafe_null_terminated_to_indexable(P) (P)
#define __unsafe_terminated_by_from_indexable(T, P, ...) (P)
#define __unsafe_null_terminated_from_indexable(P, ...) (P)

/* decay operates normally; attribute is meaningless without pointer checks. */
#define __array_decay_dicards_count_in_parameters

/* this is a write-once variable; not useful without pointer checks. */
#define __unsafe_late_const

#define __ptrcheck_unavailable
#define __ptrcheck_unavailable_r(REPLACEMENT)

#endif /* !__has_include(<ptrcheck.h>) */

#if KERNEL && !BOUND_CHECKS && !__has_ptrcheck
/*
 * With pointer checks disabled, we define __indexable to allow source to still
 * contain these annotations. This is safe in builds which _uniformly_ disable
 * pointer checks (but not in builds which inconsistently have them enabled).
 */

#define __indexable
#define __bidi_indexable
#endif

#define __ASSUME_PTR_ABI_SINGLE_BEGIN       __ptrcheck_abi_assume_single()
#define __ASSUME_PTR_ABI_SINGLE_END         __ptrcheck_abi_assume_unsafe_indexable()

#if __has_ptrcheck
#define __header_indexable                  __indexable
#define __header_bidi_indexable             __bidi_indexable
#else
#define __header_indexable
#define __header_bidi_indexable
#endif

/*
 * Architecture validation for current SDK
 */
#if !defined(__sys_cdefs_arch_unknown__) && defined(__i386__)
#elif !defined(__sys_cdefs_arch_unknown__) && defined(__x86_64__)
#elif !defined(__sys_cdefs_arch_unknown__) && defined(__arm__)
#elif !defined(__sys_cdefs_arch_unknown__) && defined(__arm64__)
#else
#error Unsupported architecture
#endif

#ifdef XNU_KERNEL_PRIVATE
/*
 * Selectively ignore cast alignment warnings
 */
#define __IGNORE_WCASTALIGN(x) _Pragma("clang diagnostic push")                     \
	                       _Pragma("clang diagnostic ignored \"-Wcast-align\"") \
	                       x                                                    \
	                       _Pragma("clang diagnostic pop")
#endif

#if defined(PRIVATE) || defined(KERNEL)
/*
 * Check if __probable and __improbable have already been defined elsewhere.
 * These macros inform the compiler (and humans) about which branches are likely
 * to be taken.
 */
#if !defined(__probable) && !defined(__improbable)
#define __probable(x)   __builtin_expect(!!(x), 1)
#define __improbable(x) __builtin_expect(!!(x), 0)
#endif /* !defined(__probable) && !defined(__improbable) */

#define __container_of(ptr, type_t, field) __extension__({ \
	const __typeof__(((type_t *)NULL)->field) *__ptr = (ptr);               \
	uintptr_t __result = (uintptr_t)__ptr - offsetof(type_t, field);        \
	if (__ptr) __builtin_assume(__result != 0);                             \
	__unsafe_forge_single(type_t *, __result);                              \
})

#define __container_of_safe(ptr, type_t, field) __extension__({ \
	const __typeof__(((type_t *)NULL)->field) *__ptr_or_null = (ptr);       \
	__ptr_or_null ? __container_of(__ptr_or_null, type_t, field) : NULL;    \
})

/*
 * This forces the optimizer to materialize the specified variable value,
 * and prevents any reordering of operations done to it.
 */
#define __compiler_materialize_and_prevent_reordering_on(var) \
	__asm__ ("" : "=r"(var) : "0"(var))

#endif /* KERNEL || PRIVATE */

#define __compiler_barrier() __asm__ __volatile__("" ::: "memory")

#if __has_attribute(enum_extensibility)
#define __enum_open __attribute__((__enum_extensibility__(open)))
#define __enum_closed __attribute__((__enum_extensibility__(closed)))
#else
#define __enum_open
#define __enum_closed
#endif // __has_attribute(enum_extensibility)

#if __has_attribute(flag_enum)
#define __enum_options __attribute__((__flag_enum__))
#else
#define __enum_options
#endif

/*
 * Similar to OS_ENUM/OS_CLOSED_ENUM/OS_OPTIONS/OS_CLOSED_OPTIONS
 *
 * This provides more advanced type checking on compilers supporting
 * the proper extensions, even in C.
 */
#if __has_feature(objc_fixed_enum) || __has_extension(cxx_fixed_enum) || \
        __has_extension(cxx_strong_enums)
#define __enum_decl(_name, _type, ...) \
	        typedef enum : _type __VA_ARGS__ __enum_open _name
#define __enum_closed_decl(_name, _type, ...) \
	        typedef enum : _type __VA_ARGS__ __enum_closed _name
#define __options_decl(_name, _type, ...) \
	        typedef enum : _type __VA_ARGS__ __enum_open __enum_options _name
#define __options_closed_decl(_name, _type, ...) \
	        typedef enum : _type __VA_ARGS__ __enum_closed __enum_options _name
#else
#define __enum_decl(_name, _type, ...) \
	        typedef _type _name; enum __VA_ARGS__ __enum_open
#define __enum_closed_decl(_name, _type, ...) \
	        typedef _type _name; enum __VA_ARGS__ __enum_closed
#define __options_decl(_name, _type, ...) \
	        typedef _type _name; enum __VA_ARGS__ __enum_open __enum_options
#define __options_closed_decl(_name, _type, ...) \
	        typedef _type _name; enum __VA_ARGS__ __enum_closed __enum_options
#endif

#if XNU_KERNEL_PRIVATE
/*
 * __xnu_struct_group() can be used to declare a set of fields to be grouped
 * together logically in order to perform safer memory operations
 * (assignment, zeroing, ...) on them.
 */
#ifdef __cplusplus
#define __xnu_struct_group(group_type, group_name, ...) \
	struct group_type __VA_ARGS__; \
	union { \
	    struct __VA_ARGS__; \
	    struct group_type group_name; \
	}
#else
#define __xnu_struct_group(group_type, group_name, ...) \
	union { \
	    struct __VA_ARGS__; \
	    struct group_type __VA_ARGS__ group_name; \
	}
#endif
#endif /* XNU_KERNEL_PRIVATE */

#if defined(KERNEL) && __has_attribute(xnu_usage_semantics)
/*
 * These macros can be used to annotate type definitions or scalar structure
 * fields to inform the compiler about which semantic they have with regards
 * to the content of the underlying memory represented by such type or field.
 *
 * This information is used in the analysis of the types performed by the
 * signature based type segregation implemented in kalloc.
 */
#define __kernel_ptr_semantics __attribute__((xnu_usage_semantics("pointer")))
#define __kernel_data_semantics __attribute__((xnu_usage_semantics("data")))
#define __kernel_dual_semantics __attribute__((xnu_usage_semantics("pointer", "data")))

#else  /* defined(KERNEL) && __has_attribute(xnu_usage_semantics) */

#define __kernel_ptr_semantics
#define __kernel_data_semantics
#define __kernel_dual_semantics

#endif /* defined(KERNEL) && __has_attribute(xnu_usage_semantics) */

#if XNU_KERNEL_PRIVATE
/*
 * Compiler-dependent macros that bracket portions of code where the
 * "-Wxnu-typed-allocators" warning should be ignored.
 */
#if defined(__clang__)
# define __typed_allocators_ignore_push \
	 _Pragma("clang diagnostic push") \
	 _Pragma("clang diagnostic ignored \"-Wxnu-typed-allocators\"")
# define __typed_allocators_ignore_pop \
	 _Pragma("clang diagnostic pop")
# define __typed_allocators_ignore(x) __typed_allocators_ignore_push \
	                              x                              \
	                              __typed_allocators_ignore_pop
#else
# define __typed_allocators_ignore_push
# define __typed_allocators_ignore_pop
# define __typed_allocators_ignore(x) x
#endif /* __clang */
#endif /* XNU_KERNEL_PRIVATE */

#if defined(KERNEL_PRIVATE) && \
        __has_attribute(xnu_data_size) && \
        __has_attribute(xnu_returns_data_pointer)
/*
 * Annotate function parameters to specify that they semantically
 * represent the size of a data-only backing storage.
 */
# define __xnu_data_size __attribute__((xnu_data_size))
/*
 * Annotate function declarations to specify that the pointer they return
 * points to a data-only backing storage.
 */
# define __xnu_returns_data_pointer __attribute__((xnu_returns_data_pointer))
#else
# define __xnu_data_size
# define __xnu_returns_data_pointer
#endif

#if XNU_KERNEL_PRIVATE
/*
 * Macro pair which allows C code to, at build time, require that a function
 * will not use a stack frame/spill to the stack in RELEASE or DEVELOPMENT (i.e.
 * not DEBUG).
 *
 * This macro has no effect on non-optimizing/-O0 builds since we rely on the
 * existence of some basic optimizations in order to ensure that stack usage can
 * be avoided. Since non-optimizing builds should never be used in production,
 * we can relax the security properties of this macro and permit stack usage
 * without an error.
 *
 * When unsupported, this macro is ignored and stack usage will not generate an
 * error. As such, this macro should only be used when stack usage may pose a
 * security concern rather than a functional issue.
 *
 * In user-space compilation the function decorated with this calls into a mock
 * function and that uses the stack, so this needs to be disabled.
 */
#if __OPTIMIZE__ && !defined(__BUILDING_XNU_LIBRARY__)
#define __SECURITY_STACK_DISALLOWED_PUSH \
	 _Pragma("clang diagnostic push") \
	 _Pragma("clang diagnostic error \"-Wframe-larger-than\"")
#define __SECURITY_STACK_DISALLOWED_POP \
	 _Pragma("clang diagnostic pop")
#else
#define __SECURITY_STACK_DISALLOWED_PUSH
#define __SECURITY_STACK_DISALLOWED_POP
#endif /* __clang */
#endif /* XNU_KERNEL_PRIVATE */

#endif /* !_CDEFS_H_ */