[mirror_frr.git] / lib / compiler.h

/*
 * Copyright (c) 2015-2017  David Lamparter, for NetDEF, Inc.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _FRR_COMPILER_H
#define _FRR_COMPILER_H

#ifdef __cplusplus
extern "C" {
#endif

/* function attributes, use like
 *   void prototype(void) __attribute__((_CONSTRUCTOR(100)));
 */
#if defined(__clang__)
#if __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 5)
#  define _RET_NONNULL    , returns_nonnull
#endif
#if __has_attribute(fallthrough)
#  define _FALLTHROUGH __attribute__((fallthrough));
#endif
# define _CONSTRUCTOR(x)  constructor(x)
# define _DEPRECATED(x) deprecated(x)
# if __has_builtin(assume)
#  define assume(x) __builtin_assume(x)
# endif
#elif defined(__GNUC__)
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 9)
#  define _RET_NONNULL    , returns_nonnull
#endif
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
#  define _CONSTRUCTOR(x) constructor(x)
#  define _DESTRUCTOR(x)  destructor(x)
#  define _ALLOC_SIZE(x)  alloc_size(x)
#endif
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
#  define _DEPRECATED(x) deprecated(x)
#  define assume(x) do { if (!(x)) __builtin_unreachable(); } while (0)
#endif
#if __GNUC__ < 5
#  define __has_attribute(x) 0
#endif
#if __GNUC__ >= 7
#  define _FALLTHROUGH __attribute__((fallthrough));
#endif
#endif

#if __has_attribute(hot)
#  define _OPTIMIZE_HOT __attribute__((hot))
#else
#  define _OPTIMIZE_HOT
#endif
#if __has_attribute(optimize)
#  define _OPTIMIZE_O3 __attribute__((optimize("3")))
#else
#  define _OPTIMIZE_O3
#endif
#define OPTIMIZE _OPTIMIZE_O3 _OPTIMIZE_HOT

#if !defined(__GNUC__)
#error module code needs GCC visibility extensions
#elif __GNUC__ < 4
#error module code needs GCC visibility extensions
#else
# define DSO_PUBLIC __attribute__ ((visibility ("default")))
# define DSO_SELF   __attribute__ ((visibility ("protected")))
# define DSO_LOCAL  __attribute__ ((visibility ("hidden")))
#endif

#ifdef __sun
/* Solaris doesn't do constructor priorities due to linker restrictions */
#undef _CONSTRUCTOR
#undef _DESTRUCTOR
#endif

/* fallback versions */
#ifndef _RET_NONNULL
# define _RET_NONNULL
#endif
#ifndef _CONSTRUCTOR
# define _CONSTRUCTOR(x) constructor
#endif
#ifndef _DESTRUCTOR
# define _DESTRUCTOR(x) destructor
#endif
#ifndef _ALLOC_SIZE
# define _ALLOC_SIZE(x)
#endif
#ifndef _FALLTHROUGH
#define _FALLTHROUGH
#endif
#ifndef _DEPRECATED
#define _DEPRECATED(x) deprecated
#endif
#ifndef assume
#define assume(x)
#endif

/* pure = function does not modify memory & return value is the same if
 * memory hasn't changed (=> allows compiler to optimize)
 *
 * Mostly autodetected by the compiler if function body is available (i.e.
 * static inline functions in headers).  Since that implies it should only be
 * used in headers for non-inline functions, the "extern" is included here.
 */
#define ext_pure	extern __attribute__((pure))

/* for helper functions defined inside macros */
#define macro_inline	static inline __attribute__((unused))
#define macro_pure	static inline __attribute__((unused, pure))


/* variadic macros, use like:
 * #define V_0()  ...
 * #define V_1(x) ...
 * #define V(...) MACRO_VARIANT(V, ##__VA_ARGS__)(__VA_ARGS__)
 */
#define _MACRO_VARIANT(A0,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10, N, ...) N

#define _CONCAT2(a, b) a ## b
#define _CONCAT(a, b) _CONCAT2(a,b)

#define MACRO_VARIANT(NAME, ...) \
	_CONCAT(NAME, _MACRO_VARIANT(0, ##__VA_ARGS__, \
			_10, _9, _8, _7, _6, _5, _4, _3, _2, _1, _0))

#define NAMECTR(name) _CONCAT(name, __COUNTER__)

/* per-arg repeat macros, use like:
 * #define PERARG(n) ...n...
 * #define FOO(...) MACRO_REPEAT(PERARG, ##__VA_ARGS__)
 */

#define _MACRO_REPEAT_0(NAME)
#define _MACRO_REPEAT_1(NAME, A1) \
	NAME(A1)
#define _MACRO_REPEAT_2(NAME, A1, A2) \
	NAME(A1) NAME(A2)
#define _MACRO_REPEAT_3(NAME, A1, A2, A3) \
	NAME(A1) NAME(A2) NAME(A3)
#define _MACRO_REPEAT_4(NAME, A1, A2, A3, A4) \
	NAME(A1) NAME(A2) NAME(A3) NAME(A4)
#define _MACRO_REPEAT_5(NAME, A1, A2, A3, A4, A5) \
	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5)
#define _MACRO_REPEAT_6(NAME, A1, A2, A3, A4, A5, A6) \
	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6)
#define _MACRO_REPEAT_7(NAME, A1, A2, A3, A4, A5, A6, A7) \
	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6) NAME(A7)
#define _MACRO_REPEAT_8(NAME, A1, A2, A3, A4, A5, A6, A7, A8) \
	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6) NAME(A7) NAME(A8)

#define MACRO_REPEAT(NAME, ...) \
	MACRO_VARIANT(_MACRO_REPEAT, ##__VA_ARGS__)(NAME, ##__VA_ARGS__)

/*
 * for warnings on macros, put in the macro content like this:
 *   #define MACRO BLA CPP_WARN("MACRO has been deprecated")
 */
#define CPP_STR(X) #X

#if defined(__ICC)
#define CPP_NOTICE(text) _Pragma(CPP_STR(message __FILE__ ": " text))
#define CPP_WARN(text) CPP_NOTICE(text)

#elif (defined(__GNUC__)                                                       \
       && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))           \
	|| (defined(__clang__)                                                 \
	    && (__clang_major__ >= 4                                           \
		|| (__clang_major__ == 3 && __clang_minor__ >= 5)))
#define CPP_WARN(text) _Pragma(CPP_STR(GCC warning text))
#define CPP_NOTICE(text) _Pragma(CPP_STR(message text))

#else
#define CPP_WARN(text)
#define CPP_NOTICE(text)
#endif

/* MAX / MIN are not commonly defined, but useful */
/* note: glibc sys/param.h has #define MIN(a,b) (((a)<(b))?(a):(b)) */
#ifdef MAX
#undef MAX
#endif
#define MAX(a, b)                                                              \
	({                                                                     \
		typeof(a) _max_a = (a);                                        \
		typeof(b) _max_b = (b);                                        \
		_max_a > _max_b ? _max_a : _max_b;                             \
	})
#ifdef MIN
#undef MIN
#endif
#define MIN(a, b)                                                              \
	({                                                                     \
		typeof(a) _min_a = (a);                                        \
		typeof(b) _min_b = (b);                                        \
		_min_a < _min_b ? _min_a : _min_b;                             \
	})

#define numcmp(a, b)                                                           \
	({                                                                     \
		typeof(a) _cmp_a = (a);                                        \
		typeof(b) _cmp_b = (b);                                        \
		(_cmp_a < _cmp_b) ? -1 : ((_cmp_a > _cmp_b) ? 1 : 0);          \
	})

#ifndef offsetof
#ifdef __compiler_offsetof
#define offsetof(TYPE, MEMBER) __compiler_offsetof(TYPE,MEMBER)
#else
#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
#endif
#endif

#ifdef container_of
#undef container_of
#endif

#if !(defined(__cplusplus) || defined(test__cplusplus))
/* this variant of container_of() retains 'const' on pointers without needing
 * to be told to do so.  The following will all work without warning:
 *
 * struct member *p;
 * const struct member *cp;
 *
 * const struct cont *x = container_of(cp, struct cont, member);
 * const struct cont *x = container_of(cp, const struct cont, member);
 * const struct cont *x = container_of(p,  struct cont, member);
 * const struct cont *x = container_of(p,  const struct cont, member);
 * struct cont *x       = container_of(p,  struct cont, member);
 *
 * but the following will generate warnings about stripping const:
 *
 * struct cont *x       = container_of(cp, struct cont, member);
 * struct cont *x       = container_of(cp, const struct cont, member);
 * struct cont *x       = container_of(p,  const struct cont, member);
 */
#define container_of(ptr, type, member)                                        \
	(__builtin_choose_expr(                                                \
		__builtin_types_compatible_p(typeof(&((type *)0)->member),     \
			typeof(ptr))                                           \
		    ||  __builtin_types_compatible_p(void *, typeof(ptr)),     \
		({                                                             \
			typeof(((type *)0)->member) *__mptr = (void *)(ptr);   \
			(type *)((char *)__mptr - offsetof(type, member));     \
		}),                                                            \
		({                                                             \
			typeof(((const type *)0)->member) *__mptr = (ptr);     \
			(const type *)((const char *)__mptr -                  \
					offsetof(type, member));               \
		})                                                             \
	))
#else
/* current C++ compilers don't have the builtins used above; so this version
 * of the macro doesn't do the const check. */
#define container_of(ptr, type, member)                                        \
		({                                                             \
			const typeof(((type *)0)->member) *__mptr = (ptr);     \
			(type *)((char *)__mptr - offsetof(type, member));     \
		})
#endif

#define container_of_null(ptr, type, member)                                   \
	({                                                                     \
		typeof(ptr) _tmp = (ptr);                                      \
		_tmp ? container_of(_tmp, type, member) : NULL;                \
	})

#define array_size(ar) (sizeof(ar) / sizeof(ar[0]))

/* sigh. this is so ugly, it overflows and wraps to being nice again.
 *
 * printfrr() supports "%Ld" for <int64_t>, whatever that is typedef'd to.
 * However, gcc & clang think that "%Ld" is <long long>, which doesn't quite
 * match up since int64_t is <long> on a lot of 64-bit systems.
 *
 * If we have _FRR_ATTRIBUTE_PRINTFRR, we loaded a compiler plugin that
 * replaces the whole format checking bits with a custom version that
 * understands "%Ld" (along with "%pI4" and co.), so we don't need to do
 * anything.
 *
 * If we don't have that attribute...  we still want -Wformat to work.  So,
 * this is the "f*ck it" approach and we just redefine int64_t to always be
 * <long long>.  This should work until such a time that <long long> is
 * something else (e.g. 128-bit integer)...  let's just guard against that
 * with the _Static_assert below and work with the world we have right now,
 * where <long long> is always 64-bit.
 */

/* these need to be included before any of the following, so we can
 * "overwrite" things.
 */
#include <stdint.h>
#include <inttypes.h>

#ifdef _FRR_ATTRIBUTE_PRINTFRR
#define PRINTFRR(a, b) __attribute__((printfrr(a, b)))

#else /* !_FRR_ATTRIBUTE_PRINTFRR */
#define PRINTFRR(a, b) __attribute__((format(printf, a, b)))

/* these should be typedefs, but might also be #define */
#ifdef uint64_t
#undef uint64_t
#endif
#ifdef int64_t
#undef int64_t
#endif

/* can't overwrite the typedef, but we can replace int64_t with _int64_t */
typedef unsigned long long _uint64_t;
#define uint64_t _uint64_t
typedef signed long long _int64_t;
#define int64_t _int64_t

/* if this breaks, 128-bit machines may have entered reality (or <long long>
 * is something weird)
 */
#if __STDC_VERSION__ >= 201112L
_Static_assert(sizeof(_uint64_t) == 8 && sizeof(_int64_t) == 8,
	       "nobody expects the spanish intquisition");
#endif

/* since we redefined int64_t, we also need to redefine PRI*64 */
#undef PRIu64
#undef PRId64
#undef PRIx64
#define PRIu64 "llu"
#define PRId64 "lld"
#define PRIx64 "llx"
#endif /* !_FRR_ATTRIBUTE_PRINTFRR */

#ifdef __cplusplus
}
#endif

#endif /* _FRR_COMPILER_H */
Commit	Line	Data
de1a880c DL	1	/*
	2	* Copyright (c) 2015-2017 David Lamparter, for NetDEF, Inc.
	3	*
	4	* Permission to use, copy, modify, and distribute this software for any
	5	* purpose with or without fee is hereby granted, provided that the above
	6	* copyright notice and this permission notice appear in all copies.
	7	*
	8	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	9	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	10	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	11	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	12	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	13	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	14	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	15	*/
	16
	17	#ifndef _FRR_COMPILER_H
	18	#define _FRR_COMPILER_H
	19
5e244469 RW	20	#ifdef __cplusplus
	21	extern "C" {
	22	#endif
	23
de1a880c DL	24	/* function attributes, use like
	25	* void prototype(void) __attribute__((_CONSTRUCTOR(100)));
	26	*/
	27	#if defined(__clang__)
996c9314	28	#if __clang_major__ > 3 \|\| (__clang_major__ == 3 && __clang_minor__ >= 5)
de1a880c	29	# define _RET_NONNULL , returns_nonnull
996c9314	30	#endif
bd27ea43 DL	31	#if __has_attribute(fallthrough)
	32	# define _FALLTHROUGH __attribute__((fallthrough));
	33	#endif
de1a880c	34	# define _CONSTRUCTOR(x) constructor(x)
bcea0c0f	35	# define _DEPRECATED(x) deprecated(x)
111a04f7 DL	36	# if __has_builtin(assume)
	37	# define assume(x) __builtin_assume(x)
	38	# endif
de1a880c	39	#elif defined(__GNUC__)
996c9314	40	#if __GNUC__ > 4 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 9)
de1a880c	41	# define _RET_NONNULL , returns_nonnull
996c9314 LB	42	#endif
996c9314 LB	43	#if __GNUC__ > 4 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
de1a880c DL	44	# define _CONSTRUCTOR(x) constructor(x)
	45	# define _DESTRUCTOR(x) destructor(x)
	46	# define _ALLOC_SIZE(x) alloc_size(x)
996c9314	47	#endif
bcea0c0f DL	48	#if __GNUC__ > 4 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
bcea0c0f DL	49	# define _DEPRECATED(x) deprecated(x)
111a04f7 DL	50	# define assume(x) do { if (!(x)) __builtin_unreachable(); } while (0)
	51	#endif
	52	#if __GNUC__ < 5
	53	# define __has_attribute(x) 0
bcea0c0f	54	#endif
bd27ea43 DL	55	#if __GNUC__ >= 7
	56	# define _FALLTHROUGH __attribute__((fallthrough));
	57	#endif
de1a880c DL	58	#endif
de1a880c DL	59
111a04f7 DL	60	#if __has_attribute(hot)
	61	# define _OPTIMIZE_HOT __attribute__((hot))
	62	#else
	63	# define _OPTIMIZE_HOT
	64	#endif
	65	#if __has_attribute(optimize)
	66	# define _OPTIMIZE_O3 __attribute__((optimize("3")))
	67	#else
	68	# define _OPTIMIZE_O3
	69	#endif
	70	#define OPTIMIZE _OPTIMIZE_O3 _OPTIMIZE_HOT
	71
8be3678a DL	72	#if !defined(__GNUC__)
	73	#error module code needs GCC visibility extensions
	74	#elif __GNUC__ < 4
	75	#error module code needs GCC visibility extensions
	76	#else
	77	# define DSO_PUBLIC __attribute__ ((visibility ("default")))
	78	# define DSO_SELF __attribute__ ((visibility ("protected")))
	79	# define DSO_LOCAL __attribute__ ((visibility ("hidden")))
	80	#endif
	81
de1a880c DL	82	#ifdef __sun
de1a880c DL	83	/* Solaris doesn't do constructor priorities due to linker restrictions */
996c9314 LB	84	#undef _CONSTRUCTOR
996c9314 LB	85	#undef _DESTRUCTOR
de1a880c DL	86	#endif
	87
	88	/* fallback versions */
	89	#ifndef _RET_NONNULL
	90	# define _RET_NONNULL
	91	#endif
	92	#ifndef _CONSTRUCTOR
	93	# define _CONSTRUCTOR(x) constructor
	94	#endif
	95	#ifndef _DESTRUCTOR
	96	# define _DESTRUCTOR(x) destructor
	97	#endif
	98	#ifndef _ALLOC_SIZE
	99	# define _ALLOC_SIZE(x)
	100	#endif
bd27ea43 DL	101	#ifndef _FALLTHROUGH
	102	#define _FALLTHROUGH
	103	#endif
bcea0c0f DL	104	#ifndef _DEPRECATED
	105	#define _DEPRECATED(x) deprecated
	106	#endif
111a04f7 DL	107	#ifndef assume
	108	#define assume(x)
	109	#endif
de1a880c	110
3b18b6c0 DL	111	/* pure = function does not modify memory & return value is the same if
	112	* memory hasn't changed (=> allows compiler to optimize)
	113	*
	114	* Mostly autodetected by the compiler if function body is available (i.e.
	115	* static inline functions in headers). Since that implies it should only be
	116	* used in headers for non-inline functions, the "extern" is included here.
	117	*/
	118	#define ext_pure extern __attribute__((pure))
	119
0d019561 DL	120	/* for helper functions defined inside macros */
	121	#define macro_inline static inline __attribute__((unused))
	122	#define macro_pure static inline __attribute__((unused, pure))
	123
48373d46 DL	124
	125	/* variadic macros, use like:
	126	* #define V_0() ...
	127	* #define V_1(x) ...
	128	* #define V(...) MACRO_VARIANT(V, ##__VA_ARGS__)(__VA_ARGS__)
	129	*/
	130	#define _MACRO_VARIANT(A0,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10, N, ...) N
	131
	132	#define _CONCAT2(a, b) a ## b
	133	#define _CONCAT(a, b) _CONCAT2(a,b)
	134
	135	#define MACRO_VARIANT(NAME, ...) \
	136	_CONCAT(NAME, _MACRO_VARIANT(0, ##__VA_ARGS__, \
	137	_10, _9, _8, _7, _6, _5, _4, _3, _2, _1, _0))
	138
	139	#define NAMECTR(name) _CONCAT(name, __COUNTER__)
	140
	141	/* per-arg repeat macros, use like:
	142	* #define PERARG(n) ...n...
	143	* #define FOO(...) MACRO_REPEAT(PERARG, ##__VA_ARGS__)
	144	*/
	145
	146	#define _MACRO_REPEAT_0(NAME)
	147	#define _MACRO_REPEAT_1(NAME, A1) \
	148	NAME(A1)
	149	#define _MACRO_REPEAT_2(NAME, A1, A2) \
	150	NAME(A1) NAME(A2)
	151	#define _MACRO_REPEAT_3(NAME, A1, A2, A3) \
	152	NAME(A1) NAME(A2) NAME(A3)
	153	#define _MACRO_REPEAT_4(NAME, A1, A2, A3, A4) \
	154	NAME(A1) NAME(A2) NAME(A3) NAME(A4)
	155	#define _MACRO_REPEAT_5(NAME, A1, A2, A3, A4, A5) \
	156	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5)
	157	#define _MACRO_REPEAT_6(NAME, A1, A2, A3, A4, A5, A6) \
	158	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6)
	159	#define _MACRO_REPEAT_7(NAME, A1, A2, A3, A4, A5, A6, A7) \
	160	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6) NAME(A7)
	161	#define _MACRO_REPEAT_8(NAME, A1, A2, A3, A4, A5, A6, A7, A8) \
	162	NAME(A1) NAME(A2) NAME(A3) NAME(A4) NAME(A5) NAME(A6) NAME(A7) NAME(A8)
	163
	164	#define MACRO_REPEAT(NAME, ...) \
	165	MACRO_VARIANT(_MACRO_REPEAT, ##__VA_ARGS__)(NAME, ##__VA_ARGS__)
	166
de1a880c DL	167	/*
	168	* for warnings on macros, put in the macro content like this:
	169	* #define MACRO BLA CPP_WARN("MACRO has been deprecated")
	170	*/
	171	#define CPP_STR(X) #X
	172
	173	#if defined(__ICC)
	174	#define CPP_NOTICE(text) _Pragma(CPP_STR(message __FILE__ ": " text))
	175	#define CPP_WARN(text) CPP_NOTICE(text)
	176
	177	#elif (defined(__GNUC__) \
	178	&& (__GNUC__ >= 5 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) \
	179	\|\| (defined(__clang__) \
	180	&& (__clang_major__ >= 4 \
	181	\|\| (__clang_major__ == 3 && __clang_minor__ >= 5)))
	182	#define CPP_WARN(text) _Pragma(CPP_STR(GCC warning text))
	183	#define CPP_NOTICE(text) _Pragma(CPP_STR(message text))
	184
	185	#else
	186	#define CPP_WARN(text)
ec40eaf9	187	#define CPP_NOTICE(text)
de1a880c DL	188	#endif
de1a880c DL	189
0d019561 DL	190	/* MAX / MIN are not commonly defined, but useful */
	191	/* note: glibc sys/param.h has #define MIN(a,b) (((a)<(b))?(a):(b)) */
	192	#ifdef MAX
	193	#undef MAX
	194	#endif
	195	#define MAX(a, b) \
	196	({ \
	197	typeof(a) _max_a = (a); \
	198	typeof(b) _max_b = (b); \
	199	_max_a > _max_b ? _max_a : _max_b; \
	200	})
	201	#ifdef MIN
	202	#undef MIN
	203	#endif
	204	#define MIN(a, b) \
	205	({ \
	206	typeof(a) _min_a = (a); \
	207	typeof(b) _min_b = (b); \
	208	_min_a < _min_b ? _min_a : _min_b; \
	209	})
	210
1315d74d DL	211	#define numcmp(a, b) \
	212	({ \
	213	typeof(a) _cmp_a = (a); \
	214	typeof(b) _cmp_b = (b); \
	215	(_cmp_a < _cmp_b) ? -1 : ((_cmp_a > _cmp_b) ? 1 : 0); \
	216	})
	217
0d019561 DL	218	#ifndef offsetof
	219	#ifdef __compiler_offsetof
	220	#define offsetof(TYPE, MEMBER) __compiler_offsetof(TYPE,MEMBER)
	221	#else
	222	#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
	223	#endif
	224	#endif
	225
a7f20d43 DL	226	#ifdef container_of
	227	#undef container_of
	228	#endif
	229
	230	#if !(defined(__cplusplus) \|\| defined(test__cplusplus))
0d019561 DL	231	/* this variant of container_of() retains 'const' on pointers without needing
	232	* to be told to do so. The following will all work without warning:
	233	*
	234	* struct member *p;
	235	* const struct member *cp;
	236	*
	237	* const struct cont *x = container_of(cp, struct cont, member);
	238	* const struct cont *x = container_of(cp, const struct cont, member);
	239	* const struct cont *x = container_of(p, struct cont, member);
	240	* const struct cont *x = container_of(p, const struct cont, member);
	241	* struct cont *x = container_of(p, struct cont, member);
	242	*
	243	* but the following will generate warnings about stripping const:
	244	*
	245	* struct cont *x = container_of(cp, struct cont, member);
	246	* struct cont *x = container_of(cp, const struct cont, member);
	247	* struct cont *x = container_of(p, const struct cont, member);
	248	*/
0d019561 DL	249	#define container_of(ptr, type, member) \
	250	(__builtin_choose_expr( \
	251	__builtin_types_compatible_p(typeof(&((type *)0)->member), \
	252	typeof(ptr)) \
	253	\|\| __builtin_types_compatible_p(void *, typeof(ptr)), \
	254	({ \
	255	typeof(((type )0)->member) __mptr = (void *)(ptr); \
	256	(type )((char )__mptr - offsetof(type, member)); \
	257	}), \
	258	({ \
	259	typeof(((const type )0)->member) __mptr = (ptr); \
	260	(const type )((const char )__mptr - \
	261	offsetof(type, member)); \
	262	}) \
	263	))
a7f20d43 DL	264	#else
	265	/* current C++ compilers don't have the builtins used above; so this version
	266	* of the macro doesn't do the const check. */
	267	#define container_of(ptr, type, member) \
	268	({ \
	269	const typeof(((type )0)->member) __mptr = (ptr); \
	270	(type )((char )__mptr - offsetof(type, member)); \
	271	})
	272	#endif
0d019561 DL	273
	274	#define container_of_null(ptr, type, member) \
	275	({ \
	276	typeof(ptr) _tmp = (ptr); \
	277	_tmp ? container_of(_tmp, type, member) : NULL; \
	278	})
	279
	280	#define array_size(ar) (sizeof(ar) / sizeof(ar[0]))
	281
afb35622 DL	282	/* sigh. this is so ugly, it overflows and wraps to being nice again.
	283	*
	284	* printfrr() supports "%Ld" for <int64_t>, whatever that is typedef'd to.
	285	* However, gcc & clang think that "%Ld" is <long long>, which doesn't quite
	286	* match up since int64_t is <long> on a lot of 64-bit systems.
	287	*
	288	* If we have _FRR_ATTRIBUTE_PRINTFRR, we loaded a compiler plugin that
	289	* replaces the whole format checking bits with a custom version that
	290	* understands "%Ld" (along with "%pI4" and co.), so we don't need to do
	291	* anything.
	292	*
	293	* If we don't have that attribute... we still want -Wformat to work. So,
	294	* this is the "f*ck it" approach and we just redefine int64_t to always be
	295	* <long long>. This should work until such a time that <long long> is
	296	* something else (e.g. 128-bit integer)... let's just guard against that
	297	* with the _Static_assert below and work with the world we have right now,
	298	* where <long long> is always 64-bit.
	299	*/
	300
	301	/* these need to be included before any of the following, so we can
	302	* "overwrite" things.
	303	*/
	304	#include <stdint.h>
	305	#include <inttypes.h>
	306
	307	#ifdef _FRR_ATTRIBUTE_PRINTFRR
	308	#define PRINTFRR(a, b) __attribute__((printfrr(a, b)))
	309
	310	#else /* !_FRR_ATTRIBUTE_PRINTFRR */
	311	#define PRINTFRR(a, b) __attribute__((format(printf, a, b)))
	312
	313	/* these should be typedefs, but might also be #define */
	314	#ifdef uint64_t
	315	#undef uint64_t
	316	#endif
	317	#ifdef int64_t
	318	#undef int64_t
	319	#endif
	320
	321	/* can't overwrite the typedef, but we can replace int64_t with _int64_t */
	322	typedef unsigned long long _uint64_t;
	323	#define uint64_t _uint64_t
	324	typedef signed long long _int64_t;
	325	#define int64_t _int64_t
	326
	327	/* if this breaks, 128-bit machines may have entered reality (or <long long>
	328	* is something weird)
	329	*/
	330	#if __STDC_VERSION__ >= 201112L
	331	_Static_assert(sizeof(_uint64_t) == 8 && sizeof(_int64_t) == 8,
	332	"nobody expects the spanish intquisition");
	333	#endif
	334
	335	/* since we redefined int64_t, we also need to redefine PRI64 /
	336	#undef PRIu64
	337	#undef PRId64
	338	#undef PRIx64
	339	#define PRIu64 "llu"
	340	#define PRId64 "lld"
	341	#define PRIx64 "llx"
	342	#endif /* !_FRR_ATTRIBUTE_PRINTFRR */
	343
5e244469 RW	344	#ifdef __cplusplus
	345	}
	346	#endif
	347
de1a880c	348	#endif /* _FRR_COMPILER_H */