xref: /freebsd/contrib/libevent/util-internal.h (revision 8d13bc63c0e1d50bc9e47ac1f26329c999bfecf0)
1 /*
2  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 #ifndef UTIL_INTERNAL_H_INCLUDED_
27 #define UTIL_INTERNAL_H_INCLUDED_
28 
29 #include "event2/event-config.h"
30 #include "evconfig-private.h"
31 
32 #include <errno.h>
33 
34 /* For EVUTIL_ASSERT */
35 #include "log-internal.h"
36 #include <stdio.h>
37 #include <stdlib.h>
38 #ifdef EVENT__HAVE_SYS_SOCKET_H
39 #include <sys/socket.h>
40 #endif
41 #ifdef EVENT__HAVE_SYS_EVENTFD_H
42 #include <sys/eventfd.h>
43 #endif
44 #include "event2/util.h"
45 
46 #include "time-internal.h"
47 #include "ipv6-internal.h"
48 
49 #ifdef __cplusplus
50 extern "C" {
51 #endif
52 
53 /* __has_attribute() wrapper */
54 #ifdef __has_attribute
55 # define EVUTIL_HAS_ATTRIBUTE __has_attribute
56 #endif
57 /** clang 3 __has_attribute misbehaves in some versions */
58 #if defined(__clang__) && __clang__ == 1
59 # if defined(__apple_build_version__)
60 #  if __clang_major__ <= 6
61 #   undef EVUTIL_HAS_ATTRIBUTE
62 #  endif
63 # else /* !__apple_build_version__ */
64 #  if __clang_major__ == 3 && __clang_minor__ >= 2 && __clang_minor__ <= 5
65 #   undef EVUTIL_HAS_ATTRIBUTE
66 #  endif
67 # endif /* __apple_build_version__ */
68 #endif /*\ defined(__clang__) && __clang__ == 1 */
69 #ifndef EVUTIL_HAS_ATTRIBUTE
70 # define EVUTIL_HAS_ATTRIBUTE(x) 0
71 #endif
72 
73 /* If we need magic to say "inline", get it for free internally. */
74 #ifdef EVENT__inline
75 #define inline EVENT__inline
76 #endif
77 
78 /* Define to appropriate substitute if compiler doesnt have __func__ */
79 #if defined(EVENT__HAVE___func__)
80 # ifndef __func__
81 #  define __func__ __func__
82 # endif
83 #elif defined(EVENT__HAVE___FUNCTION__)
84 # define __func__ __FUNCTION__
85 #else
86 # define __func__ __FILE__
87 #endif
88 
89 /* A good no-op to use in macro definitions. */
90 #define EVUTIL_NIL_STMT_ ((void)0)
91 /* A no-op that tricks the compiler into thinking a condition is used while
92  * definitely not making any code for it.  Used to compile out asserts while
93  * avoiding "unused variable" warnings.  The "!" forces the compiler to
94  * do the sizeof() on an int, in case "condition" is a bitfield value.
95  */
96 #define EVUTIL_NIL_CONDITION_(condition) do { \
97 	(void)sizeof(!(condition));  \
98 } while(0)
99 
100 /* Internal use only: macros to match patterns of error codes in a
101    cross-platform way.  We need these macros because of two historical
102    reasons: first, nonblocking IO functions are generally written to give an
103    error on the "blocked now, try later" case, so sometimes an error from a
104    read, write, connect, or accept means "no error; just wait for more
105    data," and we need to look at the error code.  Second, Windows defines
106    a different set of error codes for sockets. */
107 
108 #ifndef _WIN32
109 
110 #if EAGAIN == EWOULDBLOCK
111 #define EVUTIL_ERR_IS_EAGAIN(e) \
112 	((e) == EAGAIN)
113 #else
114 #define EVUTIL_ERR_IS_EAGAIN(e) \
115 	((e) == EAGAIN || (e) == EWOULDBLOCK)
116 #endif
117 
118 /* True iff e is an error that means a read/write operation can be retried. */
119 #define EVUTIL_ERR_RW_RETRIABLE(e)				\
120 	((e) == EINTR || EVUTIL_ERR_IS_EAGAIN(e))
121 /* True iff e is an error that means an connect can be retried. */
122 #define EVUTIL_ERR_CONNECT_RETRIABLE(e)			\
123 	((e) == EINTR || (e) == EINPROGRESS)
124 /* True iff e is an error that means a accept can be retried. */
125 #define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
126 	((e) == EINTR || EVUTIL_ERR_IS_EAGAIN(e) || (e) == ECONNABORTED)
127 
128 /* True iff e is an error that means the connection was refused */
129 #define EVUTIL_ERR_CONNECT_REFUSED(e)					\
130 	((e) == ECONNREFUSED)
131 
132 #else
133 /* Win32 */
134 
135 #define EVUTIL_ERR_IS_EAGAIN(e) \
136 	((e) == WSAEWOULDBLOCK || (e) == EAGAIN)
137 
138 #define EVUTIL_ERR_RW_RETRIABLE(e)					\
139 	((e) == WSAEWOULDBLOCK ||					\
140 	    (e) == WSAEINTR)
141 
142 #define EVUTIL_ERR_CONNECT_RETRIABLE(e)					\
143 	((e) == WSAEWOULDBLOCK ||					\
144 	    (e) == WSAEINTR ||						\
145 	    (e) == WSAEINPROGRESS ||					\
146 	    (e) == WSAEINVAL)
147 
148 #define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
149 	EVUTIL_ERR_RW_RETRIABLE(e)
150 
151 #define EVUTIL_ERR_CONNECT_REFUSED(e)					\
152 	((e) == WSAECONNREFUSED)
153 
154 #endif
155 
156 /* Arguments for shutdown() */
157 #ifdef SHUT_RD
158 #define EVUTIL_SHUT_RD SHUT_RD
159 #else
160 #define EVUTIL_SHUT_RD 0
161 #endif
162 #ifdef SHUT_WR
163 #define EVUTIL_SHUT_WR SHUT_WR
164 #else
165 #define EVUTIL_SHUT_WR 1 /* SD_SEND */
166 #endif
167 #ifdef SHUT_BOTH
168 #define EVUTIL_SHUT_BOTH SHUT_BOTH
169 #else
170 #define EVUTIL_SHUT_BOTH 2
171 #endif
172 
173 /* Helper: Verify that all the elements in 'dlist' are internally consistent.
174  * Checks for circular lists and bad prev/next pointers.
175  *
176  * Example usage:
177  *    EVUTIL_ASSERT_LIST_OK(eventlist, event, ev_next);
178  */
179 #define EVUTIL_ASSERT_LIST_OK(dlist, type, field) do {			\
180 		struct type *elm1, *elm2, **nextp;			\
181 		if (LIST_EMPTY((dlist)))				\
182 			break;						\
183 									\
184 		/* Check list for circularity using Floyd's */		\
185 		/* 'Tortoise and Hare' algorithm */			\
186 		elm1 = LIST_FIRST((dlist));				\
187 		elm2 = LIST_NEXT(elm1, field);				\
188 		while (elm1 && elm2) {					\
189 			EVUTIL_ASSERT(elm1 != elm2);			\
190 			elm1 = LIST_NEXT(elm1, field);			\
191 			elm2 = LIST_NEXT(elm2, field);			\
192 			if (!elm2)					\
193 				break;					\
194 			EVUTIL_ASSERT(elm1 != elm2);			\
195 			elm2 = LIST_NEXT(elm2, field);			\
196 		}							\
197 									\
198 		/* Now check next and prev pointers for consistency. */ \
199 		nextp = &LIST_FIRST((dlist));				\
200 		elm1 = LIST_FIRST((dlist));				\
201 		while (elm1) {						\
202 			EVUTIL_ASSERT(*nextp == elm1);			\
203 			EVUTIL_ASSERT(nextp == elm1->field.le_prev);	\
204 			nextp = &LIST_NEXT(elm1, field);		\
205 			elm1 = *nextp;					\
206 		}							\
207 	} while (0)
208 
209 /* Helper: Verify that all the elements in a TAILQ are internally consistent.
210  * Checks for circular lists and bad prev/next pointers.
211  *
212  * Example usage:
213  *    EVUTIL_ASSERT_TAILQ_OK(activelist, event, ev_active_next);
214  */
215 #define EVUTIL_ASSERT_TAILQ_OK(tailq, type, field) do {			\
216 		struct type *elm1, *elm2, **nextp;			\
217 		if (TAILQ_EMPTY((tailq)))				\
218 			break;						\
219 									\
220 		/* Check list for circularity using Floyd's */		\
221 		/* 'Tortoise and Hare' algorithm */			\
222 		elm1 = TAILQ_FIRST((tailq));				\
223 		elm2 = TAILQ_NEXT(elm1, field);				\
224 		while (elm1 && elm2) {					\
225 			EVUTIL_ASSERT(elm1 != elm2);			\
226 			elm1 = TAILQ_NEXT(elm1, field);			\
227 			elm2 = TAILQ_NEXT(elm2, field);			\
228 			if (!elm2)					\
229 				break;					\
230 			EVUTIL_ASSERT(elm1 != elm2);			\
231 			elm2 = TAILQ_NEXT(elm2, field);			\
232 		}							\
233 									\
234 		/* Now check next and prev pointers for consistency. */ \
235 		nextp = &TAILQ_FIRST((tailq));				\
236 		elm1 = TAILQ_FIRST((tailq));				\
237 		while (elm1) {						\
238 			EVUTIL_ASSERT(*nextp == elm1);			\
239 			EVUTIL_ASSERT(nextp == elm1->field.tqe_prev);	\
240 			nextp = &TAILQ_NEXT(elm1, field);		\
241 			elm1 = *nextp;					\
242 		}							\
243 		EVUTIL_ASSERT(nextp == (tailq)->tqh_last);		\
244 	} while (0)
245 
246 /* Locale-independent replacements for some ctypes functions.  Use these
247  * when you care about ASCII's notion of character types, because you are about
248  * to send those types onto the wire.
249  */
250 EVENT2_EXPORT_SYMBOL
251 int EVUTIL_ISALPHA_(char c);
252 EVENT2_EXPORT_SYMBOL
253 int EVUTIL_ISALNUM_(char c);
254 int EVUTIL_ISSPACE_(char c);
255 EVENT2_EXPORT_SYMBOL
256 int EVUTIL_ISDIGIT_(char c);
257 EVENT2_EXPORT_SYMBOL
258 int EVUTIL_ISXDIGIT_(char c);
259 int EVUTIL_ISPRINT_(char c);
260 int EVUTIL_ISLOWER_(char c);
261 int EVUTIL_ISUPPER_(char c);
262 EVENT2_EXPORT_SYMBOL
263 char EVUTIL_TOUPPER_(char c);
264 EVENT2_EXPORT_SYMBOL
265 char EVUTIL_TOLOWER_(char c);
266 
267 /** Remove all trailing horizontal whitespace (space or tab) from the end of a
268  * string */
269 EVENT2_EXPORT_SYMBOL
270 void evutil_rtrim_lws_(char *);
271 
272 
273 /** Helper macro.  If we know that a given pointer points to a field in a
274     structure, return a pointer to the structure itself.  Used to implement
275     our half-baked C OO.  Example:
276 
277     struct subtype {
278 	int x;
279 	struct supertype common;
280 	int y;
281     };
282     ...
283     void fn(struct supertype *super) {
284 	struct subtype *sub = EVUTIL_UPCAST(super, struct subtype, common);
285 	...
286     }
287  */
288 #define EVUTIL_UPCAST(ptr, type, field)				\
289 	((type *)(((char*)(ptr)) - evutil_offsetof(type, field)))
290 
291 /* As open(pathname, flags, mode), except that the file is always opened with
292  * the close-on-exec flag set. (And the mode argument is mandatory.)
293  */
294 int evutil_open_closeonexec_(const char *pathname, int flags, unsigned mode);
295 
296 EVENT2_EXPORT_SYMBOL
297 int evutil_read_file_(const char *filename, char **content_out, size_t *len_out,
298     int is_binary);
299 
300 EVENT2_EXPORT_SYMBOL
301 int evutil_socket_connect_(evutil_socket_t *fd_ptr, const struct sockaddr *sa, int socklen);
302 
303 int evutil_socket_finished_connecting_(evutil_socket_t fd);
304 
305 EVENT2_EXPORT_SYMBOL
306 int evutil_ersatz_socketpair_(int, int , int, evutil_socket_t[]);
307 
308 int evutil_resolve_(int family, const char *hostname, struct sockaddr *sa,
309     ev_socklen_t *socklen, int port);
310 
311 const char *evutil_getenv_(const char *name);
312 
313 /* Structure to hold the state of our weak random number generator.
314  */
315 struct evutil_weakrand_state {
316 	ev_uint32_t seed;
317 };
318 
319 #define EVUTIL_WEAKRAND_MAX EV_INT32_MAX
320 
321 /* Initialize the state of a week random number generator based on 'seed'.  If
322  * the seed is 0, construct a new seed based on not-very-strong platform
323  * entropy, like the PID and the time of day.
324  *
325  * This function, and the other evutil_weakrand* functions, are meant for
326  * speed, not security or statistical strength.  If you need a RNG which an
327  * attacker can't predict, or which passes strong statistical tests, use the
328  * evutil_secure_rng* functions instead.
329  */
330 EVENT2_EXPORT_SYMBOL
331 ev_uint32_t evutil_weakrand_seed_(struct evutil_weakrand_state *state, ev_uint32_t seed);
332 /* Return a pseudorandom value between 0 and EVUTIL_WEAKRAND_MAX inclusive.
333  * Updates the state in 'seed' as needed -- this value must be protected by a
334  * lock.
335  */
336 EVENT2_EXPORT_SYMBOL
337 ev_int32_t evutil_weakrand_(struct evutil_weakrand_state *seed);
338 /* Return a pseudorandom value x such that 0 <= x < top. top must be no more
339  * than EVUTIL_WEAKRAND_MAX. Updates the state in 'seed' as needed -- this
340  * value must be proteced by a lock */
341 EVENT2_EXPORT_SYMBOL
342 ev_int32_t evutil_weakrand_range_(struct evutil_weakrand_state *seed, ev_int32_t top);
343 
344 /* Evaluates to the same boolean value as 'p', and hints to the compiler that
345  * we expect this value to be false. */
346 #if defined(__GNUC__) && __GNUC__ >= 3         /* gcc 3.0 or later */
347 #define EVUTIL_UNLIKELY(p) __builtin_expect(!!(p),0)
348 #else
349 #define EVUTIL_UNLIKELY(p) (p)
350 #endif
351 
352 #if EVUTIL_HAS_ATTRIBUTE(fallthrough)
353 #define EVUTIL_FALLTHROUGH __attribute__((fallthrough))
354 #else
355 #define EVUTIL_FALLTHROUGH /* fallthrough */
356 #endif
357 
358 /* Replacement for assert() that calls event_errx on failure. */
359 #ifdef NDEBUG
360 #define EVUTIL_ASSERT(cond) EVUTIL_NIL_CONDITION_(cond)
361 #define EVUTIL_FAILURE_CHECK(cond) 0
362 #else
363 #define EVUTIL_ASSERT(cond)						\
364 	do {								\
365 		if (EVUTIL_UNLIKELY(!(cond))) {				\
366 			event_errx(EVENT_ERR_ABORT_,			\
367 			    "%s:%d: Assertion %s failed in %s",		\
368 			    __FILE__,__LINE__,#cond,__func__);		\
369 			/* In case a user-supplied handler tries to */	\
370 			/* return control to us, log and abort here. */	\
371 			(void)fprintf(stderr,				\
372 			    "%s:%d: Assertion %s failed in %s",		\
373 			    __FILE__,__LINE__,#cond,__func__);		\
374 			abort();					\
375 		}							\
376 	} while (0)
377 #define EVUTIL_FAILURE_CHECK(cond) EVUTIL_UNLIKELY(cond)
378 #endif
379 
380 #ifndef EVENT__HAVE_STRUCT_SOCKADDR_STORAGE
381 /* Replacement for sockaddr storage that we can use internally on platforms
382  * that lack it.  It is not space-efficient, but neither is sockaddr_storage.
383  */
384 struct sockaddr_storage {
385 	union {
386 		struct sockaddr ss_sa;
387 		struct sockaddr_in ss_sin;
388 		struct sockaddr_in6 ss_sin6;
389 		char ss_padding[128];
390 	} ss_union;
391 };
392 #define ss_family ss_union.ss_sa.sa_family
393 #endif
394 
395 /* Internal addrinfo error code.  This one is returned from only from
396  * evutil_getaddrinfo_common_, when we are sure that we'll have to hit a DNS
397  * server. */
398 #define EVUTIL_EAI_NEED_RESOLVE      -90002
399 
400 struct evdns_base;
401 struct evdns_getaddrinfo_request;
402 typedef struct evdns_getaddrinfo_request* (*evdns_getaddrinfo_fn)(
403     struct evdns_base *base,
404     const char *nodename, const char *servname,
405     const struct evutil_addrinfo *hints_in,
406     void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
407 EVENT2_EXPORT_SYMBOL
408 void evutil_set_evdns_getaddrinfo_fn_(evdns_getaddrinfo_fn fn);
409 typedef void (*evdns_getaddrinfo_cancel_fn)(
410     struct evdns_getaddrinfo_request *req);
411 EVENT2_EXPORT_SYMBOL
412 void evutil_set_evdns_getaddrinfo_cancel_fn_(evdns_getaddrinfo_cancel_fn fn);
413 
414 EVENT2_EXPORT_SYMBOL
415 struct evutil_addrinfo *evutil_new_addrinfo_(struct sockaddr *sa,
416     ev_socklen_t socklen, const struct evutil_addrinfo *hints);
417 EVENT2_EXPORT_SYMBOL
418 struct evutil_addrinfo *evutil_addrinfo_append_(struct evutil_addrinfo *first,
419     struct evutil_addrinfo *append);
420 EVENT2_EXPORT_SYMBOL
421 void evutil_adjust_hints_for_addrconfig_(struct evutil_addrinfo *hints);
422 EVENT2_EXPORT_SYMBOL
423 int evutil_getaddrinfo_common_(const char *nodename, const char *servname,
424     struct evutil_addrinfo *hints, struct evutil_addrinfo **res, int *portnum);
425 
426 struct evdns_getaddrinfo_request *evutil_getaddrinfo_async_(
427     struct evdns_base *dns_base,
428     const char *nodename, const char *servname,
429     const struct evutil_addrinfo *hints_in,
430     void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
431 void evutil_getaddrinfo_cancel_async_(struct evdns_getaddrinfo_request *data);
432 
433 /** Return true iff sa is a looback address. (That is, it is 127.0.0.1/8, or
434  * ::1). */
435 EVENT2_EXPORT_SYMBOL
436 int evutil_sockaddr_is_loopback_(const struct sockaddr *sa);
437 
438 
439 /**
440     Formats a sockaddr sa into a string buffer of size outlen stored in out.
441     Returns a pointer to out.  Always writes something into out, so it's safe
442     to use the output of this function without checking it for NULL.
443  */
444 EVENT2_EXPORT_SYMBOL
445 const char *evutil_format_sockaddr_port_(const struct sockaddr *sa, char *out, size_t outlen);
446 
447 int evutil_hex_char_to_int_(char c);
448 
449 
450 void evutil_free_secure_rng_globals_(void);
451 void evutil_free_globals_(void);
452 
453 #ifdef _WIN32
454 EVENT2_EXPORT_SYMBOL
455 HMODULE evutil_load_windows_system_library_(const TCHAR *library_name);
456 #endif
457 
458 #ifndef EV_SIZE_FMT
459 #if defined(_MSC_VER) || defined(__MINGW32__) || defined(__MINGW64__)
460 #define EV_U64_FMT "%I64u"
461 #define EV_I64_FMT "%I64d"
462 #define EV_I64_ARG(x) ((__int64)(x))
463 #define EV_U64_ARG(x) ((unsigned __int64)(x))
464 #else
465 #define EV_U64_FMT "%llu"
466 #define EV_I64_FMT "%lld"
467 #define EV_I64_ARG(x) ((long long)(x))
468 #define EV_U64_ARG(x) ((unsigned long long)(x))
469 #endif
470 #endif
471 
472 #ifdef _WIN32
473 #define EV_SOCK_FMT EV_I64_FMT
474 #define EV_SOCK_ARG(x) EV_I64_ARG((x))
475 #else
476 #define EV_SOCK_FMT "%d"
477 #define EV_SOCK_ARG(x) (x)
478 #endif
479 
480 #if defined(__STDC__) && defined(__STDC_VERSION__) && !defined(__MINGW64_VERSION_MAJOR)
481 #if (__STDC_VERSION__ >= 199901L)
482 #define EV_SIZE_FMT "%zu"
483 #define EV_SSIZE_FMT "%zd"
484 #define EV_SIZE_ARG(x) (x)
485 #define EV_SSIZE_ARG(x) (x)
486 #endif
487 #endif
488 
489 #ifndef EV_SIZE_FMT
490 #if (EVENT__SIZEOF_SIZE_T <= EVENT__SIZEOF_LONG)
491 #define EV_SIZE_FMT "%lu"
492 #define EV_SSIZE_FMT "%ld"
493 #define EV_SIZE_ARG(x) ((unsigned long)(x))
494 #define EV_SSIZE_ARG(x) ((long)(x))
495 #else
496 #define EV_SIZE_FMT EV_U64_FMT
497 #define EV_SSIZE_FMT EV_I64_FMT
498 #define EV_SIZE_ARG(x) EV_U64_ARG(x)
499 #define EV_SSIZE_ARG(x) EV_I64_ARG(x)
500 #endif
501 #endif
502 
503 EVENT2_EXPORT_SYMBOL
504 evutil_socket_t evutil_socket_(int domain, int type, int protocol);
505 evutil_socket_t evutil_accept4_(evutil_socket_t sockfd, struct sockaddr *addr,
506     ev_socklen_t *addrlen, int flags);
507 
508     /* used by one of the test programs.. */
509 EVENT2_EXPORT_SYMBOL
510 int evutil_make_internal_pipe_(evutil_socket_t fd[2]);
511 evutil_socket_t evutil_eventfd_(unsigned initval, int flags);
512 
513 #ifdef SOCK_NONBLOCK
514 #define EVUTIL_SOCK_NONBLOCK SOCK_NONBLOCK
515 #else
516 #define EVUTIL_SOCK_NONBLOCK 0x4000000
517 #endif
518 #ifdef SOCK_CLOEXEC
519 #define EVUTIL_SOCK_CLOEXEC SOCK_CLOEXEC
520 #else
521 #define EVUTIL_SOCK_CLOEXEC 0x80000000
522 #endif
523 #ifdef EFD_NONBLOCK
524 #define EVUTIL_EFD_NONBLOCK EFD_NONBLOCK
525 #else
526 #define EVUTIL_EFD_NONBLOCK 0x4000
527 #endif
528 #ifdef EFD_CLOEXEC
529 #define EVUTIL_EFD_CLOEXEC EFD_CLOEXEC
530 #else
531 #define EVUTIL_EFD_CLOEXEC 0x8000
532 #endif
533 
534 void evutil_memclear_(void *mem, size_t len);
535 
536 struct in_addr;
537 struct in6_addr;
538 
539 /* This is a any, loopback, link-local, multicast */
540 EVENT2_EXPORT_SYMBOL
541 int evutil_v4addr_is_local_(const struct in_addr *in);
542 /* This is a reserved, ipv4compat, ipv4map, loopback,
543  * link-local, multicast, or unspecified address. */
544 EVENT2_EXPORT_SYMBOL
545 int evutil_v6addr_is_local_(const struct in6_addr *in);
546 
547 #ifdef __cplusplus
548 }
549 #endif
550 
551 #endif
552