1 /*
2  * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu>
3  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 #include "event2/event-config.h"
28 #include "evconfig-private.h"
29 
30 #ifdef _WIN32
31 #include <winsock2.h>
32 #define WIN32_LEAN_AND_MEAN
33 #include <windows.h>
34 #undef WIN32_LEAN_AND_MEAN
35 #endif
36 #include <sys/types.h>
37 #if !defined(_WIN32) && defined(EVENT__HAVE_SYS_TIME_H)
38 #include <sys/time.h>
39 #endif
40 #include <sys/queue.h>
41 #ifdef EVENT__HAVE_SYS_SOCKET_H
42 #include <sys/socket.h>
43 #endif
44 #include <stdio.h>
45 #include <stdlib.h>
46 #ifdef EVENT__HAVE_UNISTD_H
47 #include <unistd.h>
48 #endif
49 #include <ctype.h>
50 #include <errno.h>
51 #include <signal.h>
52 #include <string.h>
53 #include <time.h>
54 #include <limits.h>
55 #ifdef EVENT__HAVE_FCNTL_H
56 #include <fcntl.h>
57 #endif
58 
59 #include "event2/event.h"
60 #include "event2/event_struct.h"
61 #include "event2/event_compat.h"
62 #include "event-internal.h"
63 #include "defer-internal.h"
64 #include "evthread-internal.h"
65 #include "event2/thread.h"
66 #include "event2/util.h"
67 #include "log-internal.h"
68 #include "evmap-internal.h"
69 #include "iocp-internal.h"
70 #include "changelist-internal.h"
71 #define HT_NO_CACHE_HASH_VALUES
72 #include "ht-internal.h"
73 #include "util-internal.h"
74 
75 
76 #ifdef EVENT__HAVE_WORKING_KQUEUE
77 #include "kqueue-internal.h"
78 #endif
79 
80 #ifdef EVENT__HAVE_EVENT_PORTS
81 extern const struct eventop evportops;
82 #endif
83 #ifdef EVENT__HAVE_SELECT
84 extern const struct eventop selectops;
85 #endif
86 #ifdef EVENT__HAVE_POLL
87 extern const struct eventop pollops;
88 #endif
89 #ifdef EVENT__HAVE_EPOLL
90 extern const struct eventop epollops;
91 #endif
92 #ifdef EVENT__HAVE_WORKING_KQUEUE
93 extern const struct eventop kqops;
94 #endif
95 #ifdef EVENT__HAVE_DEVPOLL
96 extern const struct eventop devpollops;
97 #endif
98 #ifdef _WIN32
99 extern const struct eventop win32ops;
100 #endif
101 
102 /* Array of backends in order of preference. */
103 static const struct eventop *eventops[] = {
104 #ifdef EVENT__HAVE_EVENT_PORTS
105 	&evportops,
106 #endif
107 #ifdef EVENT__HAVE_WORKING_KQUEUE
108 	&kqops,
109 #endif
110 #ifdef EVENT__HAVE_EPOLL
111 	&epollops,
112 #endif
113 #ifdef EVENT__HAVE_DEVPOLL
114 	&devpollops,
115 #endif
116 #ifdef EVENT__HAVE_POLL
117 	&pollops,
118 #endif
119 #ifdef EVENT__HAVE_SELECT
120 	&selectops,
121 #endif
122 #ifdef _WIN32
123 	&win32ops,
124 #endif
125 	NULL
126 };
127 
128 /* Global state; deprecated */
129 EVENT2_EXPORT_SYMBOL
130 struct event_base *event_global_current_base_ = NULL;
131 #define current_base event_global_current_base_
132 
133 /* Global state */
134 
135 static void *event_self_cbarg_ptr_ = NULL;
136 
137 /* Prototypes */
138 static void	event_queue_insert_active(struct event_base *, struct event_callback *);
139 static void	event_queue_insert_active_later(struct event_base *, struct event_callback *);
140 static void	event_queue_insert_timeout(struct event_base *, struct event *);
141 static void	event_queue_insert_inserted(struct event_base *, struct event *);
142 static void	event_queue_remove_active(struct event_base *, struct event_callback *);
143 static void	event_queue_remove_active_later(struct event_base *, struct event_callback *);
144 static void	event_queue_remove_timeout(struct event_base *, struct event *);
145 static void	event_queue_remove_inserted(struct event_base *, struct event *);
146 static void event_queue_make_later_events_active(struct event_base *base);
147 
148 static int evthread_make_base_notifiable_nolock_(struct event_base *base);
149 static int event_del_(struct event *ev, int blocking);
150 
151 #ifdef USE_REINSERT_TIMEOUT
152 /* This code seems buggy; only turn it on if we find out what the trouble is. */
153 static void	event_queue_reinsert_timeout(struct event_base *,struct event *, int was_common, int is_common, int old_timeout_idx);
154 #endif
155 
156 static int	event_haveevents(struct event_base *);
157 
158 static int	event_process_active(struct event_base *);
159 
160 static int	timeout_next(struct event_base *, struct timeval **);
161 static void	timeout_process(struct event_base *);
162 
163 static inline void	event_signal_closure(struct event_base *, struct event *ev);
164 static inline void	event_persist_closure(struct event_base *, struct event *ev);
165 
166 static int	evthread_notify_base(struct event_base *base);
167 
168 static void insert_common_timeout_inorder(struct common_timeout_list *ctl,
169     struct event *ev);
170 
171 #ifndef EVENT__DISABLE_DEBUG_MODE
172 /* These functions implement a hashtable of which 'struct event *' structures
173  * have been setup or added.  We don't want to trust the content of the struct
174  * event itself, since we're trying to work through cases where an event gets
175  * clobbered or freed.  Instead, we keep a hashtable indexed by the pointer.
176  */
177 
178 struct event_debug_entry {
179 	HT_ENTRY(event_debug_entry) node;
180 	const struct event *ptr;
181 	unsigned added : 1;
182 };
183 
184 static inline unsigned
hash_debug_entry(const struct event_debug_entry * e)185 hash_debug_entry(const struct event_debug_entry *e)
186 {
187 	/* We need to do this silliness to convince compilers that we
188 	 * honestly mean to cast e->ptr to an integer, and discard any
189 	 * part of it that doesn't fit in an unsigned.
190 	 */
191 	unsigned u = (unsigned) ((ev_uintptr_t) e->ptr);
192 	/* Our hashtable implementation is pretty sensitive to low bits,
193 	 * and every struct event is over 64 bytes in size, so we can
194 	 * just say >>6. */
195 	return (u >> 6);
196 }
197 
198 static inline int
eq_debug_entry(const struct event_debug_entry * a,const struct event_debug_entry * b)199 eq_debug_entry(const struct event_debug_entry *a,
200     const struct event_debug_entry *b)
201 {
202 	return a->ptr == b->ptr;
203 }
204 
205 int event_debug_mode_on_ = 0;
206 
207 
208 #if !defined(EVENT__DISABLE_THREAD_SUPPORT) && !defined(EVENT__DISABLE_DEBUG_MODE)
209 /**
210  * @brief debug mode variable which is set for any function/structure that needs
211  *        to be shared across threads (if thread support is enabled).
212  *
213  *        When and if evthreads are initialized, this variable will be evaluated,
214  *        and if set to something other than zero, this means the evthread setup
215  *        functions were called out of order.
216  *
217  *        See: "Locks and threading" in the documentation.
218  */
219 int event_debug_created_threadable_ctx_ = 0;
220 #endif
221 
222 /* Set if it's too late to enable event_debug_mode. */
223 static int event_debug_mode_too_late = 0;
224 #ifndef EVENT__DISABLE_THREAD_SUPPORT
225 static void *event_debug_map_lock_ = NULL;
226 #endif
227 static HT_HEAD(event_debug_map, event_debug_entry) global_debug_map =
228 	HT_INITIALIZER();
229 
HT_PROTOTYPE(event_debug_map,event_debug_entry,node,hash_debug_entry,eq_debug_entry)230 HT_PROTOTYPE(event_debug_map, event_debug_entry, node, hash_debug_entry,
231     eq_debug_entry)
232 HT_GENERATE(event_debug_map, event_debug_entry, node, hash_debug_entry,
233     eq_debug_entry, 0.5, mm_malloc, mm_realloc, mm_free)
234 
235 /* record that ev is now setup (that is, ready for an add) */
236 static void event_debug_note_setup_(const struct event *ev)
237 {
238 	struct event_debug_entry *dent, find;
239 
240 	if (!event_debug_mode_on_)
241 		goto out;
242 
243 	find.ptr = ev;
244 	EVLOCK_LOCK(event_debug_map_lock_, 0);
245 	dent = HT_FIND(event_debug_map, &global_debug_map, &find);
246 	if (dent) {
247 		dent->added = 0;
248 	} else {
249 		dent = mm_malloc(sizeof(*dent));
250 		if (!dent)
251 			event_err(1,
252 			    "Out of memory in debugging code");
253 		dent->ptr = ev;
254 		dent->added = 0;
255 		HT_INSERT(event_debug_map, &global_debug_map, dent);
256 	}
257 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
258 
259 out:
260 	event_debug_mode_too_late = 1;
261 }
262 /* record that ev is no longer setup */
event_debug_note_teardown_(const struct event * ev)263 static void event_debug_note_teardown_(const struct event *ev)
264 {
265 	struct event_debug_entry *dent, find;
266 
267 	if (!event_debug_mode_on_)
268 		goto out;
269 
270 	find.ptr = ev;
271 	EVLOCK_LOCK(event_debug_map_lock_, 0);
272 	dent = HT_REMOVE(event_debug_map, &global_debug_map, &find);
273 	if (dent)
274 		mm_free(dent);
275 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
276 
277 out:
278 	event_debug_mode_too_late = 1;
279 }
280 /* Macro: record that ev is now added */
event_debug_note_add_(const struct event * ev)281 static void event_debug_note_add_(const struct event *ev)
282 {
283 	struct event_debug_entry *dent,find;
284 
285 	if (!event_debug_mode_on_)
286 		goto out;
287 
288 	find.ptr = ev;
289 	EVLOCK_LOCK(event_debug_map_lock_, 0);
290 	dent = HT_FIND(event_debug_map, &global_debug_map, &find);
291 	if (dent) {
292 		dent->added = 1;
293 	} else {
294 		event_errx(EVENT_ERR_ABORT_,
295 		    "%s: noting an add on a non-setup event %p"
296 		    " (events: 0x%x, fd: "EV_SOCK_FMT
297 		    ", flags: 0x%x)",
298 		    __func__, ev, ev->ev_events,
299 		    EV_SOCK_ARG(ev->ev_fd), ev->ev_flags);
300 	}
301 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
302 
303 out:
304 	event_debug_mode_too_late = 1;
305 }
306 /* record that ev is no longer added */
event_debug_note_del_(const struct event * ev)307 static void event_debug_note_del_(const struct event *ev)
308 {
309 	struct event_debug_entry *dent, find;
310 
311 	if (!event_debug_mode_on_)
312 		goto out;
313 
314 	find.ptr = ev;
315 	EVLOCK_LOCK(event_debug_map_lock_, 0);
316 	dent = HT_FIND(event_debug_map, &global_debug_map, &find);
317 	if (dent) {
318 		dent->added = 0;
319 	} else {
320 		event_errx(EVENT_ERR_ABORT_,
321 		    "%s: noting a del on a non-setup event %p"
322 		    " (events: 0x%x, fd: "EV_SOCK_FMT
323 		    ", flags: 0x%x)",
324 		    __func__, ev, ev->ev_events,
325 		    EV_SOCK_ARG(ev->ev_fd), ev->ev_flags);
326 	}
327 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
328 
329 out:
330 	event_debug_mode_too_late = 1;
331 }
332 /* assert that ev is setup (i.e., okay to add or inspect) */
event_debug_assert_is_setup_(const struct event * ev)333 static void event_debug_assert_is_setup_(const struct event *ev)
334 {
335 	struct event_debug_entry *dent, find;
336 
337 	if (!event_debug_mode_on_)
338 		return;
339 
340 	find.ptr = ev;
341 	EVLOCK_LOCK(event_debug_map_lock_, 0);
342 	dent = HT_FIND(event_debug_map, &global_debug_map, &find);
343 	if (!dent) {
344 		event_errx(EVENT_ERR_ABORT_,
345 		    "%s called on a non-initialized event %p"
346 		    " (events: 0x%x, fd: "EV_SOCK_FMT
347 		    ", flags: 0x%x)",
348 		    __func__, ev, ev->ev_events,
349 		    EV_SOCK_ARG(ev->ev_fd), ev->ev_flags);
350 	}
351 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
352 }
353 /* assert that ev is not added (i.e., okay to tear down or set up again) */
event_debug_assert_not_added_(const struct event * ev)354 static void event_debug_assert_not_added_(const struct event *ev)
355 {
356 	struct event_debug_entry *dent, find;
357 
358 	if (!event_debug_mode_on_)
359 		return;
360 
361 	find.ptr = ev;
362 	EVLOCK_LOCK(event_debug_map_lock_, 0);
363 	dent = HT_FIND(event_debug_map, &global_debug_map, &find);
364 	if (dent && dent->added) {
365 		event_errx(EVENT_ERR_ABORT_,
366 		    "%s called on an already added event %p"
367 		    " (events: 0x%x, fd: "EV_SOCK_FMT", "
368 		    "flags: 0x%x)",
369 		    __func__, ev, ev->ev_events,
370 		    EV_SOCK_ARG(ev->ev_fd), ev->ev_flags);
371 	}
372 	EVLOCK_UNLOCK(event_debug_map_lock_, 0);
373 }
event_debug_assert_socket_nonblocking_(evutil_socket_t fd)374 static void event_debug_assert_socket_nonblocking_(evutil_socket_t fd)
375 {
376 	if (!event_debug_mode_on_)
377 		return;
378 	if (fd < 0)
379 		return;
380 
381 #ifndef _WIN32
382 	{
383 		int flags;
384 		if ((flags = fcntl(fd, F_GETFL, NULL)) >= 0) {
385 			EVUTIL_ASSERT(flags & O_NONBLOCK);
386 		}
387 	}
388 #endif
389 }
390 #else
event_debug_note_setup_(const struct event * ev)391 static void event_debug_note_setup_(const struct event *ev) { (void)ev; }
event_debug_note_teardown_(const struct event * ev)392 static void event_debug_note_teardown_(const struct event *ev) { (void)ev; }
event_debug_note_add_(const struct event * ev)393 static void event_debug_note_add_(const struct event *ev) { (void)ev; }
event_debug_note_del_(const struct event * ev)394 static void event_debug_note_del_(const struct event *ev) { (void)ev; }
event_debug_assert_is_setup_(const struct event * ev)395 static void event_debug_assert_is_setup_(const struct event *ev) { (void)ev; }
event_debug_assert_not_added_(const struct event * ev)396 static void event_debug_assert_not_added_(const struct event *ev) { (void)ev; }
event_debug_assert_socket_nonblocking_(evutil_socket_t fd)397 static void event_debug_assert_socket_nonblocking_(evutil_socket_t fd) { (void)fd; }
398 #endif
399 
400 #define EVENT_BASE_ASSERT_LOCKED(base)		\
401 	EVLOCK_ASSERT_LOCKED((base)->th_base_lock)
402 
403 /* How often (in seconds) do we check for changes in wall clock time relative
404  * to monotonic time?  Set this to -1 for 'never.' */
405 #define CLOCK_SYNC_INTERVAL 5
406 
407 /** Set 'tp' to the current time according to 'base'.  We must hold the lock
408  * on 'base'.  If there is a cached time, return it.  Otherwise, use
409  * clock_gettime or gettimeofday as appropriate to find out the right time.
410  * Return 0 on success, -1 on failure.
411  */
412 static int
gettime(struct event_base * base,struct timeval * tp)413 gettime(struct event_base *base, struct timeval *tp)
414 {
415 	EVENT_BASE_ASSERT_LOCKED(base);
416 
417 	if (base->tv_cache.tv_sec) {
418 		*tp = base->tv_cache;
419 		return (0);
420 	}
421 
422 	if (evutil_gettime_monotonic_(&base->monotonic_timer, tp) == -1) {
423 		return -1;
424 	}
425 
426 	if (base->last_updated_clock_diff + CLOCK_SYNC_INTERVAL
427 	    < tp->tv_sec) {
428 		struct timeval tv;
429 		evutil_gettimeofday(&tv,NULL);
430 		evutil_timersub(&tv, tp, &base->tv_clock_diff);
431 		base->last_updated_clock_diff = tp->tv_sec;
432 	}
433 
434 	return 0;
435 }
436 
437 int
event_base_gettimeofday_cached(struct event_base * base,struct timeval * tv)438 event_base_gettimeofday_cached(struct event_base *base, struct timeval *tv)
439 {
440 	int r;
441 	if (!base) {
442 		base = current_base;
443 		if (!current_base)
444 			return evutil_gettimeofday(tv, NULL);
445 	}
446 
447 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
448 	if (base->tv_cache.tv_sec == 0) {
449 		r = evutil_gettimeofday(tv, NULL);
450 	} else {
451 		evutil_timeradd(&base->tv_cache, &base->tv_clock_diff, tv);
452 		r = 0;
453 	}
454 	EVBASE_RELEASE_LOCK(base, th_base_lock);
455 	return r;
456 }
457 
458 /** Make 'base' have no current cached time. */
459 static inline void
clear_time_cache(struct event_base * base)460 clear_time_cache(struct event_base *base)
461 {
462 	base->tv_cache.tv_sec = 0;
463 }
464 
465 /** Replace the cached time in 'base' with the current time. */
466 static inline void
update_time_cache(struct event_base * base)467 update_time_cache(struct event_base *base)
468 {
469 	base->tv_cache.tv_sec = 0;
470 	if (!(base->flags & EVENT_BASE_FLAG_NO_CACHE_TIME))
471 	    gettime(base, &base->tv_cache);
472 }
473 
474 int
event_base_update_cache_time(struct event_base * base)475 event_base_update_cache_time(struct event_base *base)
476 {
477 
478 	if (!base) {
479 		base = current_base;
480 		if (!current_base)
481 			return -1;
482 	}
483 
484 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
485 	if (base->running_loop)
486 		update_time_cache(base);
487 	EVBASE_RELEASE_LOCK(base, th_base_lock);
488 	return 0;
489 }
490 
491 static inline struct event *
event_callback_to_event(struct event_callback * evcb)492 event_callback_to_event(struct event_callback *evcb)
493 {
494 	EVUTIL_ASSERT((evcb->evcb_flags & EVLIST_INIT));
495 	return EVUTIL_UPCAST(evcb, struct event, ev_evcallback);
496 }
497 
498 static inline struct event_callback *
event_to_event_callback(struct event * ev)499 event_to_event_callback(struct event *ev)
500 {
501 	return &ev->ev_evcallback;
502 }
503 
504 struct event_base *
event_init(void)505 event_init(void)
506 {
507 	struct event_base *base = event_base_new_with_config(NULL);
508 
509 	if (base == NULL) {
510 		event_errx(1, "%s: Unable to construct event_base", __func__);
511 		return NULL;
512 	}
513 
514 	current_base = base;
515 
516 	return (base);
517 }
518 
519 struct event_base *
event_base_new(void)520 event_base_new(void)
521 {
522 	struct event_base *base = NULL;
523 	struct event_config *cfg = event_config_new();
524 	if (cfg) {
525 		base = event_base_new_with_config(cfg);
526 		event_config_free(cfg);
527 	}
528 	return base;
529 }
530 
531 /** Return true iff 'method' is the name of a method that 'cfg' tells us to
532  * avoid. */
533 static int
event_config_is_avoided_method(const struct event_config * cfg,const char * method)534 event_config_is_avoided_method(const struct event_config *cfg,
535     const char *method)
536 {
537 	struct event_config_entry *entry;
538 
539 	TAILQ_FOREACH(entry, &cfg->entries, next) {
540 		if (entry->avoid_method != NULL &&
541 		    strcmp(entry->avoid_method, method) == 0)
542 			return (1);
543 	}
544 
545 	return (0);
546 }
547 
548 /** Return true iff 'method' is disabled according to the environment. */
549 static int
event_is_method_disabled(const char * name)550 event_is_method_disabled(const char *name)
551 {
552 	char environment[64];
553 	int i;
554 
555 	evutil_snprintf(environment, sizeof(environment), "EVENT_NO%s", name);
556 	for (i = 8; environment[i] != '\0'; ++i)
557 		environment[i] = EVUTIL_TOUPPER_(environment[i]);
558 	/* Note that evutil_getenv_() ignores the environment entirely if
559 	 * we're setuid */
560 	return (evutil_getenv_(environment) != NULL);
561 }
562 
563 int
event_base_get_features(const struct event_base * base)564 event_base_get_features(const struct event_base *base)
565 {
566 	return base->evsel->features;
567 }
568 
569 void
event_enable_debug_mode(void)570 event_enable_debug_mode(void)
571 {
572 #ifndef EVENT__DISABLE_DEBUG_MODE
573 	if (event_debug_mode_on_)
574 		event_errx(1, "%s was called twice!", __func__);
575 	if (event_debug_mode_too_late)
576 		event_errx(1, "%s must be called *before* creating any events "
577 		    "or event_bases",__func__);
578 
579 	event_debug_mode_on_ = 1;
580 
581 	HT_INIT(event_debug_map, &global_debug_map);
582 #endif
583 }
584 
585 void
event_disable_debug_mode(void)586 event_disable_debug_mode(void)
587 {
588 #ifndef EVENT__DISABLE_DEBUG_MODE
589 	struct event_debug_entry **ent, *victim;
590 
591 	EVLOCK_LOCK(event_debug_map_lock_, 0);
592 	for (ent = HT_START(event_debug_map, &global_debug_map); ent; ) {
593 		victim = *ent;
594 		ent = HT_NEXT_RMV(event_debug_map, &global_debug_map, ent);
595 		mm_free(victim);
596 	}
597 	HT_CLEAR(event_debug_map, &global_debug_map);
598 	EVLOCK_UNLOCK(event_debug_map_lock_ , 0);
599 
600 	event_debug_mode_on_  = 0;
601 #endif
602 }
603 
604 struct event_base *
event_base_new_with_config(const struct event_config * cfg)605 event_base_new_with_config(const struct event_config *cfg)
606 {
607 	int i;
608 	struct event_base *base;
609 	int should_check_environment;
610 
611 #ifndef EVENT__DISABLE_DEBUG_MODE
612 	event_debug_mode_too_late = 1;
613 #endif
614 
615 	if ((base = mm_calloc(1, sizeof(struct event_base))) == NULL) {
616 		event_warn("%s: calloc", __func__);
617 		return NULL;
618 	}
619 
620 	if (cfg)
621 		base->flags = cfg->flags;
622 
623 	should_check_environment =
624 	    !(cfg && (cfg->flags & EVENT_BASE_FLAG_IGNORE_ENV));
625 
626 	{
627 		struct timeval tmp;
628 		int precise_time =
629 		    cfg && (cfg->flags & EVENT_BASE_FLAG_PRECISE_TIMER);
630 		int flags;
631 		if (should_check_environment && !precise_time) {
632 			precise_time = evutil_getenv_("EVENT_PRECISE_TIMER") != NULL;
633 			if (precise_time) {
634 				base->flags |= EVENT_BASE_FLAG_PRECISE_TIMER;
635 			}
636 		}
637 		flags = precise_time ? EV_MONOT_PRECISE : 0;
638 		evutil_configure_monotonic_time_(&base->monotonic_timer, flags);
639 
640 		gettime(base, &tmp);
641 	}
642 
643 	min_heap_ctor_(&base->timeheap);
644 
645 	base->sig.ev_signal_pair[0] = -1;
646 	base->sig.ev_signal_pair[1] = -1;
647 	base->th_notify_fd[0] = -1;
648 	base->th_notify_fd[1] = -1;
649 
650 	TAILQ_INIT(&base->active_later_queue);
651 
652 	evmap_io_initmap_(&base->io);
653 	evmap_signal_initmap_(&base->sigmap);
654 	event_changelist_init_(&base->changelist);
655 
656 	base->evbase = NULL;
657 
658 	if (cfg) {
659 		memcpy(&base->max_dispatch_time,
660 		    &cfg->max_dispatch_interval, sizeof(struct timeval));
661 		base->limit_callbacks_after_prio =
662 		    cfg->limit_callbacks_after_prio;
663 	} else {
664 		base->max_dispatch_time.tv_sec = -1;
665 		base->limit_callbacks_after_prio = 1;
666 	}
667 	if (cfg && cfg->max_dispatch_callbacks >= 0) {
668 		base->max_dispatch_callbacks = cfg->max_dispatch_callbacks;
669 	} else {
670 		base->max_dispatch_callbacks = INT_MAX;
671 	}
672 	if (base->max_dispatch_callbacks == INT_MAX &&
673 	    base->max_dispatch_time.tv_sec == -1)
674 		base->limit_callbacks_after_prio = INT_MAX;
675 
676 	for (i = 0; eventops[i] && !base->evbase; i++) {
677 		if (cfg != NULL) {
678 			/* determine if this backend should be avoided */
679 			if (event_config_is_avoided_method(cfg,
680 				eventops[i]->name))
681 				continue;
682 			if ((eventops[i]->features & cfg->require_features)
683 			    != cfg->require_features)
684 				continue;
685 		}
686 
687 		/* also obey the environment variables */
688 		if (should_check_environment &&
689 		    event_is_method_disabled(eventops[i]->name))
690 			continue;
691 
692 		base->evsel = eventops[i];
693 
694 		base->evbase = base->evsel->init(base);
695 	}
696 
697 	if (base->evbase == NULL) {
698 		event_warnx("%s: no event mechanism available",
699 		    __func__);
700 		base->evsel = NULL;
701 		event_base_free(base);
702 		return NULL;
703 	}
704 
705 	if (evutil_getenv_("EVENT_SHOW_METHOD"))
706 		event_msgx("libevent using: %s", base->evsel->name);
707 
708 	/* allocate a single active event queue */
709 	if (event_base_priority_init(base, 1) < 0) {
710 		event_base_free(base);
711 		return NULL;
712 	}
713 
714 	/* prepare for threading */
715 
716 #if !defined(EVENT__DISABLE_THREAD_SUPPORT) && !defined(EVENT__DISABLE_DEBUG_MODE)
717 	event_debug_created_threadable_ctx_ = 1;
718 #endif
719 
720 #ifndef EVENT__DISABLE_THREAD_SUPPORT
721 	if (EVTHREAD_LOCKING_ENABLED() &&
722 	    (!cfg || !(cfg->flags & EVENT_BASE_FLAG_NOLOCK))) {
723 		int r;
724 		EVTHREAD_ALLOC_LOCK(base->th_base_lock, 0);
725 		EVTHREAD_ALLOC_COND(base->current_event_cond);
726 		r = evthread_make_base_notifiable(base);
727 		if (r<0) {
728 			event_warnx("%s: Unable to make base notifiable.", __func__);
729 			event_base_free(base);
730 			return NULL;
731 		}
732 	}
733 #endif
734 
735 #ifdef _WIN32
736 	if (cfg && (cfg->flags & EVENT_BASE_FLAG_STARTUP_IOCP))
737 		event_base_start_iocp_(base, cfg->n_cpus_hint);
738 #endif
739 
740 	return (base);
741 }
742 
743 int
event_base_start_iocp_(struct event_base * base,int n_cpus)744 event_base_start_iocp_(struct event_base *base, int n_cpus)
745 {
746 #ifdef _WIN32
747 	if (base->iocp)
748 		return 0;
749 	base->iocp = event_iocp_port_launch_(n_cpus);
750 	if (!base->iocp) {
751 		event_warnx("%s: Couldn't launch IOCP", __func__);
752 		return -1;
753 	}
754 	return 0;
755 #else
756 	return -1;
757 #endif
758 }
759 
760 void
event_base_stop_iocp_(struct event_base * base)761 event_base_stop_iocp_(struct event_base *base)
762 {
763 #ifdef _WIN32
764 	int rv;
765 
766 	if (!base->iocp)
767 		return;
768 	rv = event_iocp_shutdown_(base->iocp, -1);
769 	EVUTIL_ASSERT(rv >= 0);
770 	base->iocp = NULL;
771 #endif
772 }
773 
774 static int
event_base_cancel_single_callback_(struct event_base * base,struct event_callback * evcb,int run_finalizers)775 event_base_cancel_single_callback_(struct event_base *base,
776     struct event_callback *evcb,
777     int run_finalizers)
778 {
779 	int result = 0;
780 
781 	if (evcb->evcb_flags & EVLIST_INIT) {
782 		struct event *ev = event_callback_to_event(evcb);
783 		if (!(ev->ev_flags & EVLIST_INTERNAL)) {
784 			event_del_(ev, EVENT_DEL_EVEN_IF_FINALIZING);
785 			result = 1;
786 		}
787 	} else {
788 		EVBASE_ACQUIRE_LOCK(base, th_base_lock);
789 		event_callback_cancel_nolock_(base, evcb, 1);
790 		EVBASE_RELEASE_LOCK(base, th_base_lock);
791 		result = 1;
792 	}
793 
794 	if (run_finalizers && (evcb->evcb_flags & EVLIST_FINALIZING)) {
795 		switch (evcb->evcb_closure) {
796 		case EV_CLOSURE_EVENT_FINALIZE:
797 		case EV_CLOSURE_EVENT_FINALIZE_FREE: {
798 			struct event *ev = event_callback_to_event(evcb);
799 			ev->ev_evcallback.evcb_cb_union.evcb_evfinalize(ev, ev->ev_arg);
800 			if (evcb->evcb_closure == EV_CLOSURE_EVENT_FINALIZE_FREE)
801 				mm_free(ev);
802 			break;
803 		}
804 		case EV_CLOSURE_CB_FINALIZE:
805 			evcb->evcb_cb_union.evcb_cbfinalize(evcb, evcb->evcb_arg);
806 			break;
807 		default:
808 			break;
809 		}
810 	}
811 	return result;
812 }
813 
event_base_free_queues_(struct event_base * base,int run_finalizers)814 static int event_base_free_queues_(struct event_base *base, int run_finalizers)
815 {
816 	int deleted = 0, i;
817 
818 	for (i = 0; i < base->nactivequeues; ++i) {
819 		struct event_callback *evcb, *next;
820 		for (evcb = TAILQ_FIRST(&base->activequeues[i]); evcb; ) {
821 			next = TAILQ_NEXT(evcb, evcb_active_next);
822 			deleted += event_base_cancel_single_callback_(base, evcb, run_finalizers);
823 			evcb = next;
824 		}
825 	}
826 
827 	{
828 		struct event_callback *evcb;
829 		while ((evcb = TAILQ_FIRST(&base->active_later_queue))) {
830 			deleted += event_base_cancel_single_callback_(base, evcb, run_finalizers);
831 		}
832 	}
833 
834 	return deleted;
835 }
836 
837 static void
event_base_free_(struct event_base * base,int run_finalizers)838 event_base_free_(struct event_base *base, int run_finalizers)
839 {
840 	int i, n_deleted=0;
841 	struct event *ev;
842 	/* XXXX grab the lock? If there is contention when one thread frees
843 	 * the base, then the contending thread will be very sad soon. */
844 
845 	/* event_base_free(NULL) is how to free the current_base if we
846 	 * made it with event_init and forgot to hold a reference to it. */
847 	if (base == NULL && current_base)
848 		base = current_base;
849 	/* Don't actually free NULL. */
850 	if (base == NULL) {
851 		event_warnx("%s: no base to free", __func__);
852 		return;
853 	}
854 	/* XXX(niels) - check for internal events first */
855 
856 #ifdef _WIN32
857 	event_base_stop_iocp_(base);
858 #endif
859 
860 	/* threading fds if we have them */
861 	if (base->th_notify_fd[0] != -1) {
862 		event_del(&base->th_notify);
863 		EVUTIL_CLOSESOCKET(base->th_notify_fd[0]);
864 		if (base->th_notify_fd[1] != -1)
865 			EVUTIL_CLOSESOCKET(base->th_notify_fd[1]);
866 		base->th_notify_fd[0] = -1;
867 		base->th_notify_fd[1] = -1;
868 		event_debug_unassign(&base->th_notify);
869 	}
870 
871 	/* Delete all non-internal events. */
872 	evmap_delete_all_(base);
873 
874 	while ((ev = min_heap_top_(&base->timeheap)) != NULL) {
875 		event_del(ev);
876 		++n_deleted;
877 	}
878 	for (i = 0; i < base->n_common_timeouts; ++i) {
879 		struct common_timeout_list *ctl =
880 		    base->common_timeout_queues[i];
881 		event_del(&ctl->timeout_event); /* Internal; doesn't count */
882 		event_debug_unassign(&ctl->timeout_event);
883 		for (ev = TAILQ_FIRST(&ctl->events); ev; ) {
884 			struct event *next = TAILQ_NEXT(ev,
885 			    ev_timeout_pos.ev_next_with_common_timeout);
886 			if (!(ev->ev_flags & EVLIST_INTERNAL)) {
887 				event_del(ev);
888 				++n_deleted;
889 			}
890 			ev = next;
891 		}
892 		mm_free(ctl);
893 	}
894 	if (base->common_timeout_queues)
895 		mm_free(base->common_timeout_queues);
896 
897 	for (;;) {
898 		/* For finalizers we can register yet another finalizer out from
899 		 * finalizer, and iff finalizer will be in active_later_queue we can
900 		 * add finalizer to activequeues, and we will have events in
901 		 * activequeues after this function returns, which is not what we want
902 		 * (we even have an assertion for this).
903 		 *
904 		 * A simple case is bufferevent with underlying (i.e. filters).
905 		 */
906 		int i = event_base_free_queues_(base, run_finalizers);
907 		event_debug(("%s: %d events freed", __func__, i));
908 		if (!i) {
909 			break;
910 		}
911 		n_deleted += i;
912 	}
913 
914 	if (n_deleted)
915 		event_debug(("%s: %d events were still set in base",
916 			__func__, n_deleted));
917 
918 	while (LIST_FIRST(&base->once_events)) {
919 		struct event_once *eonce = LIST_FIRST(&base->once_events);
920 		LIST_REMOVE(eonce, next_once);
921 		mm_free(eonce);
922 	}
923 
924 	if (base->evsel != NULL && base->evsel->dealloc != NULL)
925 		base->evsel->dealloc(base);
926 
927 	for (i = 0; i < base->nactivequeues; ++i)
928 		EVUTIL_ASSERT(TAILQ_EMPTY(&base->activequeues[i]));
929 
930 	EVUTIL_ASSERT(min_heap_empty_(&base->timeheap));
931 	min_heap_dtor_(&base->timeheap);
932 
933 	mm_free(base->activequeues);
934 
935 	evmap_io_clear_(&base->io);
936 	evmap_signal_clear_(&base->sigmap);
937 	event_changelist_freemem_(&base->changelist);
938 
939 	EVTHREAD_FREE_LOCK(base->th_base_lock, 0);
940 	EVTHREAD_FREE_COND(base->current_event_cond);
941 
942 	/* If we're freeing current_base, there won't be a current_base. */
943 	if (base == current_base)
944 		current_base = NULL;
945 	mm_free(base);
946 }
947 
948 void
event_base_free_nofinalize(struct event_base * base)949 event_base_free_nofinalize(struct event_base *base)
950 {
951 	event_base_free_(base, 0);
952 }
953 
954 void
event_base_free(struct event_base * base)955 event_base_free(struct event_base *base)
956 {
957 	event_base_free_(base, 1);
958 }
959 
960 /* Fake eventop; used to disable the backend temporarily inside event_reinit
961  * so that we can call event_del() on an event without telling the backend.
962  */
963 static int
nil_backend_del(struct event_base * b,evutil_socket_t fd,short old,short events,void * fdinfo)964 nil_backend_del(struct event_base *b, evutil_socket_t fd, short old,
965     short events, void *fdinfo)
966 {
967 	return 0;
968 }
969 const struct eventop nil_eventop = {
970 	"nil",
971 	NULL, /* init: unused. */
972 	NULL, /* add: unused. */
973 	nil_backend_del, /* del: used, so needs to be killed. */
974 	NULL, /* dispatch: unused. */
975 	NULL, /* dealloc: unused. */
976 	0, 0, 0
977 };
978 
979 /* reinitialize the event base after a fork */
980 int
event_reinit(struct event_base * base)981 event_reinit(struct event_base *base)
982 {
983 	const struct eventop *evsel;
984 	int res = 0;
985 	int was_notifiable = 0;
986 	int had_signal_added = 0;
987 
988 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
989 
990 	if (base->running_loop) {
991 		event_warnx("%s: forked from the event_loop.", __func__);
992 		res = -1;
993 		goto done;
994 	}
995 
996 	evsel = base->evsel;
997 
998 	/* check if this event mechanism requires reinit on the backend */
999 	if (evsel->need_reinit) {
1000 		/* We're going to call event_del() on our notify events (the
1001 		 * ones that tell about signals and wakeup events).  But we
1002 		 * don't actually want to tell the backend to change its
1003 		 * state, since it might still share some resource (a kqueue,
1004 		 * an epoll fd) with the parent process, and we don't want to
1005 		 * delete the fds from _that_ backend, we temporarily stub out
1006 		 * the evsel with a replacement.
1007 		 */
1008 		base->evsel = &nil_eventop;
1009 	}
1010 
1011 	/* We need to re-create a new signal-notification fd and a new
1012 	 * thread-notification fd.  Otherwise, we'll still share those with
1013 	 * the parent process, which would make any notification sent to them
1014 	 * get received by one or both of the event loops, more or less at
1015 	 * random.
1016 	 */
1017 	if (base->sig.ev_signal_added) {
1018 		event_del_nolock_(&base->sig.ev_signal, EVENT_DEL_AUTOBLOCK);
1019 		event_debug_unassign(&base->sig.ev_signal);
1020 		memset(&base->sig.ev_signal, 0, sizeof(base->sig.ev_signal));
1021 		had_signal_added = 1;
1022 		base->sig.ev_signal_added = 0;
1023 	}
1024 	if (base->sig.ev_signal_pair[0] != -1)
1025 		EVUTIL_CLOSESOCKET(base->sig.ev_signal_pair[0]);
1026 	if (base->sig.ev_signal_pair[1] != -1)
1027 		EVUTIL_CLOSESOCKET(base->sig.ev_signal_pair[1]);
1028 	if (base->th_notify_fn != NULL) {
1029 		was_notifiable = 1;
1030 		base->th_notify_fn = NULL;
1031 	}
1032 	if (base->th_notify_fd[0] != -1) {
1033 		event_del_nolock_(&base->th_notify, EVENT_DEL_AUTOBLOCK);
1034 		EVUTIL_CLOSESOCKET(base->th_notify_fd[0]);
1035 		if (base->th_notify_fd[1] != -1)
1036 			EVUTIL_CLOSESOCKET(base->th_notify_fd[1]);
1037 		base->th_notify_fd[0] = -1;
1038 		base->th_notify_fd[1] = -1;
1039 		event_debug_unassign(&base->th_notify);
1040 	}
1041 
1042 	/* Replace the original evsel. */
1043         base->evsel = evsel;
1044 
1045 	if (evsel->need_reinit) {
1046 		/* Reconstruct the backend through brute-force, so that we do
1047 		 * not share any structures with the parent process. For some
1048 		 * backends, this is necessary: epoll and kqueue, for
1049 		 * instance, have events associated with a kernel
1050 		 * structure. If didn't reinitialize, we'd share that
1051 		 * structure with the parent process, and any changes made by
1052 		 * the parent would affect our backend's behavior (and vice
1053 		 * versa).
1054 		 */
1055 		if (base->evsel->dealloc != NULL)
1056 			base->evsel->dealloc(base);
1057 		base->evbase = evsel->init(base);
1058 		if (base->evbase == NULL) {
1059 			event_errx(1,
1060 			   "%s: could not reinitialize event mechanism",
1061 			   __func__);
1062 			res = -1;
1063 			goto done;
1064 		}
1065 
1066 		/* Empty out the changelist (if any): we are starting from a
1067 		 * blank slate. */
1068 		event_changelist_freemem_(&base->changelist);
1069 
1070 		/* Tell the event maps to re-inform the backend about all
1071 		 * pending events. This will make the signal notification
1072 		 * event get re-created if necessary. */
1073 		if (evmap_reinit_(base) < 0)
1074 			res = -1;
1075 	} else {
1076 		res = evsig_init_(base);
1077 		if (res == 0 && had_signal_added) {
1078 			res = event_add_nolock_(&base->sig.ev_signal, NULL, 0);
1079 			if (res == 0)
1080 				base->sig.ev_signal_added = 1;
1081 		}
1082 	}
1083 
1084 	/* If we were notifiable before, and nothing just exploded, become
1085 	 * notifiable again. */
1086 	if (was_notifiable && res == 0)
1087 		res = evthread_make_base_notifiable_nolock_(base);
1088 
1089 done:
1090 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1091 	return (res);
1092 }
1093 
1094 /* Get the monotonic time for this event_base' timer */
1095 int
event_gettime_monotonic(struct event_base * base,struct timeval * tv)1096 event_gettime_monotonic(struct event_base *base, struct timeval *tv)
1097 {
1098   int rv = -1;
1099 
1100   if (base && tv) {
1101     EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1102     rv = evutil_gettime_monotonic_(&(base->monotonic_timer), tv);
1103     EVBASE_RELEASE_LOCK(base, th_base_lock);
1104   }
1105 
1106   return rv;
1107 }
1108 
1109 const char **
event_get_supported_methods(void)1110 event_get_supported_methods(void)
1111 {
1112 	static const char **methods = NULL;
1113 	const struct eventop **method;
1114 	const char **tmp;
1115 	int i = 0, k;
1116 
1117 	/* count all methods */
1118 	for (method = &eventops[0]; *method != NULL; ++method) {
1119 		++i;
1120 	}
1121 
1122 	/* allocate one more than we need for the NULL pointer */
1123 	tmp = mm_calloc((i + 1), sizeof(char *));
1124 	if (tmp == NULL)
1125 		return (NULL);
1126 
1127 	/* populate the array with the supported methods */
1128 	for (k = 0, i = 0; eventops[k] != NULL; ++k) {
1129 		tmp[i++] = eventops[k]->name;
1130 	}
1131 	tmp[i] = NULL;
1132 
1133 	if (methods != NULL)
1134 		mm_free((char**)methods);
1135 
1136 	methods = tmp;
1137 
1138 	return (methods);
1139 }
1140 
1141 struct event_config *
event_config_new(void)1142 event_config_new(void)
1143 {
1144 	struct event_config *cfg = mm_calloc(1, sizeof(*cfg));
1145 
1146 	if (cfg == NULL)
1147 		return (NULL);
1148 
1149 	TAILQ_INIT(&cfg->entries);
1150 	cfg->max_dispatch_interval.tv_sec = -1;
1151 	cfg->max_dispatch_callbacks = INT_MAX;
1152 	cfg->limit_callbacks_after_prio = 1;
1153 
1154 	return (cfg);
1155 }
1156 
1157 static void
event_config_entry_free(struct event_config_entry * entry)1158 event_config_entry_free(struct event_config_entry *entry)
1159 {
1160 	if (entry->avoid_method != NULL)
1161 		mm_free((char *)entry->avoid_method);
1162 	mm_free(entry);
1163 }
1164 
1165 void
event_config_free(struct event_config * cfg)1166 event_config_free(struct event_config *cfg)
1167 {
1168 	struct event_config_entry *entry;
1169 
1170 	while ((entry = TAILQ_FIRST(&cfg->entries)) != NULL) {
1171 		TAILQ_REMOVE(&cfg->entries, entry, next);
1172 		event_config_entry_free(entry);
1173 	}
1174 	mm_free(cfg);
1175 }
1176 
1177 int
event_config_set_flag(struct event_config * cfg,int flag)1178 event_config_set_flag(struct event_config *cfg, int flag)
1179 {
1180 	if (!cfg)
1181 		return -1;
1182 	cfg->flags |= flag;
1183 	return 0;
1184 }
1185 
1186 int
event_config_avoid_method(struct event_config * cfg,const char * method)1187 event_config_avoid_method(struct event_config *cfg, const char *method)
1188 {
1189 	struct event_config_entry *entry = mm_malloc(sizeof(*entry));
1190 	if (entry == NULL)
1191 		return (-1);
1192 
1193 	if ((entry->avoid_method = mm_strdup(method)) == NULL) {
1194 		mm_free(entry);
1195 		return (-1);
1196 	}
1197 
1198 	TAILQ_INSERT_TAIL(&cfg->entries, entry, next);
1199 
1200 	return (0);
1201 }
1202 
1203 int
event_config_require_features(struct event_config * cfg,int features)1204 event_config_require_features(struct event_config *cfg,
1205     int features)
1206 {
1207 	if (!cfg)
1208 		return (-1);
1209 	cfg->require_features = features;
1210 	return (0);
1211 }
1212 
1213 int
event_config_set_num_cpus_hint(struct event_config * cfg,int cpus)1214 event_config_set_num_cpus_hint(struct event_config *cfg, int cpus)
1215 {
1216 	if (!cfg)
1217 		return (-1);
1218 	cfg->n_cpus_hint = cpus;
1219 	return (0);
1220 }
1221 
1222 int
event_config_set_max_dispatch_interval(struct event_config * cfg,const struct timeval * max_interval,int max_callbacks,int min_priority)1223 event_config_set_max_dispatch_interval(struct event_config *cfg,
1224     const struct timeval *max_interval, int max_callbacks, int min_priority)
1225 {
1226 	if (max_interval)
1227 		memcpy(&cfg->max_dispatch_interval, max_interval,
1228 		    sizeof(struct timeval));
1229 	else
1230 		cfg->max_dispatch_interval.tv_sec = -1;
1231 	cfg->max_dispatch_callbacks =
1232 	    max_callbacks >= 0 ? max_callbacks : INT_MAX;
1233 	if (min_priority < 0)
1234 		min_priority = 0;
1235 	cfg->limit_callbacks_after_prio = min_priority;
1236 	return (0);
1237 }
1238 
1239 int
event_priority_init(int npriorities)1240 event_priority_init(int npriorities)
1241 {
1242 	return event_base_priority_init(current_base, npriorities);
1243 }
1244 
1245 int
event_base_priority_init(struct event_base * base,int npriorities)1246 event_base_priority_init(struct event_base *base, int npriorities)
1247 {
1248 	int i, r;
1249 	r = -1;
1250 
1251 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1252 
1253 	if (N_ACTIVE_CALLBACKS(base) || npriorities < 1
1254 	    || npriorities >= EVENT_MAX_PRIORITIES)
1255 		goto err;
1256 
1257 	if (npriorities == base->nactivequeues)
1258 		goto ok;
1259 
1260 	if (base->nactivequeues) {
1261 		mm_free(base->activequeues);
1262 		base->nactivequeues = 0;
1263 	}
1264 
1265 	/* Allocate our priority queues */
1266 	base->activequeues = (struct evcallback_list *)
1267 	  mm_calloc(npriorities, sizeof(struct evcallback_list));
1268 	if (base->activequeues == NULL) {
1269 		event_warn("%s: calloc", __func__);
1270 		goto err;
1271 	}
1272 	base->nactivequeues = npriorities;
1273 
1274 	for (i = 0; i < base->nactivequeues; ++i) {
1275 		TAILQ_INIT(&base->activequeues[i]);
1276 	}
1277 
1278 ok:
1279 	r = 0;
1280 err:
1281 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1282 	return (r);
1283 }
1284 
1285 int
event_base_get_npriorities(struct event_base * base)1286 event_base_get_npriorities(struct event_base *base)
1287 {
1288 
1289 	int n;
1290 	if (base == NULL)
1291 		base = current_base;
1292 
1293 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1294 	n = base->nactivequeues;
1295 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1296 	return (n);
1297 }
1298 
1299 int
event_base_get_num_events(struct event_base * base,unsigned int type)1300 event_base_get_num_events(struct event_base *base, unsigned int type)
1301 {
1302 	int r = 0;
1303 
1304 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1305 
1306 	if (type & EVENT_BASE_COUNT_ACTIVE)
1307 		r += base->event_count_active;
1308 
1309 	if (type & EVENT_BASE_COUNT_VIRTUAL)
1310 		r += base->virtual_event_count;
1311 
1312 	if (type & EVENT_BASE_COUNT_ADDED)
1313 		r += base->event_count;
1314 
1315 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1316 
1317 	return r;
1318 }
1319 
1320 int
event_base_get_max_events(struct event_base * base,unsigned int type,int clear)1321 event_base_get_max_events(struct event_base *base, unsigned int type, int clear)
1322 {
1323 	int r = 0;
1324 
1325 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1326 
1327 	if (type & EVENT_BASE_COUNT_ACTIVE) {
1328 		r += base->event_count_active_max;
1329 		if (clear)
1330 			base->event_count_active_max = 0;
1331 	}
1332 
1333 	if (type & EVENT_BASE_COUNT_VIRTUAL) {
1334 		r += base->virtual_event_count_max;
1335 		if (clear)
1336 			base->virtual_event_count_max = 0;
1337 	}
1338 
1339 	if (type & EVENT_BASE_COUNT_ADDED) {
1340 		r += base->event_count_max;
1341 		if (clear)
1342 			base->event_count_max = 0;
1343 	}
1344 
1345 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1346 
1347 	return r;
1348 }
1349 
1350 /* Returns true iff we're currently watching any events. */
1351 static int
event_haveevents(struct event_base * base)1352 event_haveevents(struct event_base *base)
1353 {
1354 	/* Caller must hold th_base_lock */
1355 	return (base->virtual_event_count > 0 || base->event_count > 0);
1356 }
1357 
1358 /* "closure" function called when processing active signal events */
1359 static inline void
event_signal_closure(struct event_base * base,struct event * ev)1360 event_signal_closure(struct event_base *base, struct event *ev)
1361 {
1362 	short ncalls;
1363 	int should_break;
1364 
1365 	/* Allows deletes to work */
1366 	ncalls = ev->ev_ncalls;
1367 	if (ncalls != 0)
1368 		ev->ev_pncalls = &ncalls;
1369 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1370 	while (ncalls) {
1371 		ncalls--;
1372 		ev->ev_ncalls = ncalls;
1373 		if (ncalls == 0)
1374 			ev->ev_pncalls = NULL;
1375 		(*ev->ev_callback)(ev->ev_fd, ev->ev_res, ev->ev_arg);
1376 
1377 		EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1378 		should_break = base->event_break;
1379 		EVBASE_RELEASE_LOCK(base, th_base_lock);
1380 
1381 		if (should_break) {
1382 			if (ncalls != 0)
1383 				ev->ev_pncalls = NULL;
1384 			return;
1385 		}
1386 	}
1387 }
1388 
1389 /* Common timeouts are special timeouts that are handled as queues rather than
1390  * in the minheap.  This is more efficient than the minheap if we happen to
1391  * know that we're going to get several thousands of timeout events all with
1392  * the same timeout value.
1393  *
1394  * Since all our timeout handling code assumes timevals can be copied,
1395  * assigned, etc, we can't use "magic pointer" to encode these common
1396  * timeouts.  Searching through a list to see if every timeout is common could
1397  * also get inefficient.  Instead, we take advantage of the fact that tv_usec
1398  * is 32 bits long, but only uses 20 of those bits (since it can never be over
1399  * 999999.)  We use the top bits to encode 4 bites of magic number, and 8 bits
1400  * of index into the event_base's aray of common timeouts.
1401  */
1402 
1403 #define MICROSECONDS_MASK       COMMON_TIMEOUT_MICROSECONDS_MASK
1404 #define COMMON_TIMEOUT_IDX_MASK 0x0ff00000
1405 #define COMMON_TIMEOUT_IDX_SHIFT 20
1406 #define COMMON_TIMEOUT_MASK     0xf0000000
1407 #define COMMON_TIMEOUT_MAGIC    0x50000000
1408 
1409 #define COMMON_TIMEOUT_IDX(tv) \
1410 	(((tv)->tv_usec & COMMON_TIMEOUT_IDX_MASK)>>COMMON_TIMEOUT_IDX_SHIFT)
1411 
1412 /** Return true iff if 'tv' is a common timeout in 'base' */
1413 static inline int
is_common_timeout(const struct timeval * tv,const struct event_base * base)1414 is_common_timeout(const struct timeval *tv,
1415     const struct event_base *base)
1416 {
1417 	int idx;
1418 	if ((tv->tv_usec & COMMON_TIMEOUT_MASK) != COMMON_TIMEOUT_MAGIC)
1419 		return 0;
1420 	idx = COMMON_TIMEOUT_IDX(tv);
1421 	return idx < base->n_common_timeouts;
1422 }
1423 
1424 /* True iff tv1 and tv2 have the same common-timeout index, or if neither
1425  * one is a common timeout. */
1426 static inline int
is_same_common_timeout(const struct timeval * tv1,const struct timeval * tv2)1427 is_same_common_timeout(const struct timeval *tv1, const struct timeval *tv2)
1428 {
1429 	return (tv1->tv_usec & ~MICROSECONDS_MASK) ==
1430 	    (tv2->tv_usec & ~MICROSECONDS_MASK);
1431 }
1432 
1433 /** Requires that 'tv' is a common timeout.  Return the corresponding
1434  * common_timeout_list. */
1435 static inline struct common_timeout_list *
get_common_timeout_list(struct event_base * base,const struct timeval * tv)1436 get_common_timeout_list(struct event_base *base, const struct timeval *tv)
1437 {
1438 	return base->common_timeout_queues[COMMON_TIMEOUT_IDX(tv)];
1439 }
1440 
1441 #if 0
1442 static inline int
1443 common_timeout_ok(const struct timeval *tv,
1444     struct event_base *base)
1445 {
1446 	const struct timeval *expect =
1447 	    &get_common_timeout_list(base, tv)->duration;
1448 	return tv->tv_sec == expect->tv_sec &&
1449 	    tv->tv_usec == expect->tv_usec;
1450 }
1451 #endif
1452 
1453 /* Add the timeout for the first event in given common timeout list to the
1454  * event_base's minheap. */
1455 static void
common_timeout_schedule(struct common_timeout_list * ctl,const struct timeval * now,struct event * head)1456 common_timeout_schedule(struct common_timeout_list *ctl,
1457     const struct timeval *now, struct event *head)
1458 {
1459 	struct timeval timeout = head->ev_timeout;
1460 	timeout.tv_usec &= MICROSECONDS_MASK;
1461 	event_add_nolock_(&ctl->timeout_event, &timeout, 1);
1462 }
1463 
1464 /* Callback: invoked when the timeout for a common timeout queue triggers.
1465  * This means that (at least) the first event in that queue should be run,
1466  * and the timeout should be rescheduled if there are more events. */
1467 static void
common_timeout_callback(evutil_socket_t fd,short what,void * arg)1468 common_timeout_callback(evutil_socket_t fd, short what, void *arg)
1469 {
1470 	struct timeval now;
1471 	struct common_timeout_list *ctl = arg;
1472 	struct event_base *base = ctl->base;
1473 	struct event *ev = NULL;
1474 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1475 	gettime(base, &now);
1476 	while (1) {
1477 		ev = TAILQ_FIRST(&ctl->events);
1478 		if (!ev || ev->ev_timeout.tv_sec > now.tv_sec ||
1479 		    (ev->ev_timeout.tv_sec == now.tv_sec &&
1480 			(ev->ev_timeout.tv_usec&MICROSECONDS_MASK) > now.tv_usec))
1481 			break;
1482 		event_del_nolock_(ev, EVENT_DEL_NOBLOCK);
1483 		event_active_nolock_(ev, EV_TIMEOUT, 1);
1484 	}
1485 	if (ev)
1486 		common_timeout_schedule(ctl, &now, ev);
1487 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1488 }
1489 
1490 #define MAX_COMMON_TIMEOUTS 256
1491 
1492 const struct timeval *
event_base_init_common_timeout(struct event_base * base,const struct timeval * duration)1493 event_base_init_common_timeout(struct event_base *base,
1494     const struct timeval *duration)
1495 {
1496 	int i;
1497 	struct timeval tv;
1498 	const struct timeval *result=NULL;
1499 	struct common_timeout_list *new_ctl;
1500 
1501 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1502 	if (duration->tv_usec > 1000000) {
1503 		memcpy(&tv, duration, sizeof(struct timeval));
1504 		if (is_common_timeout(duration, base))
1505 			tv.tv_usec &= MICROSECONDS_MASK;
1506 		tv.tv_sec += tv.tv_usec / 1000000;
1507 		tv.tv_usec %= 1000000;
1508 		duration = &tv;
1509 	}
1510 	for (i = 0; i < base->n_common_timeouts; ++i) {
1511 		const struct common_timeout_list *ctl =
1512 		    base->common_timeout_queues[i];
1513 		if (duration->tv_sec == ctl->duration.tv_sec &&
1514 		    duration->tv_usec ==
1515 		    (ctl->duration.tv_usec & MICROSECONDS_MASK)) {
1516 			EVUTIL_ASSERT(is_common_timeout(&ctl->duration, base));
1517 			result = &ctl->duration;
1518 			goto done;
1519 		}
1520 	}
1521 	if (base->n_common_timeouts == MAX_COMMON_TIMEOUTS) {
1522 		event_warnx("%s: Too many common timeouts already in use; "
1523 		    "we only support %d per event_base", __func__,
1524 		    MAX_COMMON_TIMEOUTS);
1525 		goto done;
1526 	}
1527 	if (base->n_common_timeouts_allocated == base->n_common_timeouts) {
1528 		int n = base->n_common_timeouts < 16 ? 16 :
1529 		    base->n_common_timeouts*2;
1530 		struct common_timeout_list **newqueues =
1531 		    mm_realloc(base->common_timeout_queues,
1532 			n*sizeof(struct common_timeout_queue *));
1533 		if (!newqueues) {
1534 			event_warn("%s: realloc",__func__);
1535 			goto done;
1536 		}
1537 		base->n_common_timeouts_allocated = n;
1538 		base->common_timeout_queues = newqueues;
1539 	}
1540 	new_ctl = mm_calloc(1, sizeof(struct common_timeout_list));
1541 	if (!new_ctl) {
1542 		event_warn("%s: calloc",__func__);
1543 		goto done;
1544 	}
1545 	TAILQ_INIT(&new_ctl->events);
1546 	new_ctl->duration.tv_sec = duration->tv_sec;
1547 	new_ctl->duration.tv_usec =
1548 	    duration->tv_usec | COMMON_TIMEOUT_MAGIC |
1549 	    (base->n_common_timeouts << COMMON_TIMEOUT_IDX_SHIFT);
1550 	evtimer_assign(&new_ctl->timeout_event, base,
1551 	    common_timeout_callback, new_ctl);
1552 	new_ctl->timeout_event.ev_flags |= EVLIST_INTERNAL;
1553 	event_priority_set(&new_ctl->timeout_event, 0);
1554 	new_ctl->base = base;
1555 	base->common_timeout_queues[base->n_common_timeouts++] = new_ctl;
1556 	result = &new_ctl->duration;
1557 
1558 done:
1559 	if (result)
1560 		EVUTIL_ASSERT(is_common_timeout(result, base));
1561 
1562 	EVBASE_RELEASE_LOCK(base, th_base_lock);
1563 	return result;
1564 }
1565 
1566 /* Closure function invoked when we're activating a persistent event. */
1567 static inline void
event_persist_closure(struct event_base * base,struct event * ev)1568 event_persist_closure(struct event_base *base, struct event *ev)
1569 {
1570 	void (*evcb_callback)(evutil_socket_t, short, void *);
1571 
1572         // Other fields of *ev that must be stored before executing
1573         evutil_socket_t evcb_fd;
1574         short evcb_res;
1575         void *evcb_arg;
1576 
1577 	/* reschedule the persistent event if we have a timeout. */
1578 	if (ev->ev_io_timeout.tv_sec || ev->ev_io_timeout.tv_usec) {
1579 		/* If there was a timeout, we want it to run at an interval of
1580 		 * ev_io_timeout after the last time it was _scheduled_ for,
1581 		 * not ev_io_timeout after _now_.  If it fired for another
1582 		 * reason, though, the timeout ought to start ticking _now_. */
1583 		struct timeval run_at, relative_to, delay, now;
1584 		ev_uint32_t usec_mask = 0;
1585 		EVUTIL_ASSERT(is_same_common_timeout(&ev->ev_timeout,
1586 			&ev->ev_io_timeout));
1587 		gettime(base, &now);
1588 		if (is_common_timeout(&ev->ev_timeout, base)) {
1589 			delay = ev->ev_io_timeout;
1590 			usec_mask = delay.tv_usec & ~MICROSECONDS_MASK;
1591 			delay.tv_usec &= MICROSECONDS_MASK;
1592 			if (ev->ev_res & EV_TIMEOUT) {
1593 				relative_to = ev->ev_timeout;
1594 				relative_to.tv_usec &= MICROSECONDS_MASK;
1595 			} else {
1596 				relative_to = now;
1597 			}
1598 		} else {
1599 			delay = ev->ev_io_timeout;
1600 			if (ev->ev_res & EV_TIMEOUT) {
1601 				relative_to = ev->ev_timeout;
1602 			} else {
1603 				relative_to = now;
1604 			}
1605 		}
1606 		evutil_timeradd(&relative_to, &delay, &run_at);
1607 		if (evutil_timercmp(&run_at, &now, <)) {
1608 			/* Looks like we missed at least one invocation due to
1609 			 * a clock jump, not running the event loop for a
1610 			 * while, really slow callbacks, or
1611 			 * something. Reschedule relative to now.
1612 			 */
1613 			evutil_timeradd(&now, &delay, &run_at);
1614 		}
1615 		run_at.tv_usec |= usec_mask;
1616 		event_add_nolock_(ev, &run_at, 1);
1617 	}
1618 
1619 	// Save our callback before we release the lock
1620 	evcb_callback = ev->ev_callback;
1621         evcb_fd = ev->ev_fd;
1622         evcb_res = ev->ev_res;
1623         evcb_arg = ev->ev_arg;
1624 
1625 	// Release the lock
1626  	EVBASE_RELEASE_LOCK(base, th_base_lock);
1627 
1628 	// Execute the callback
1629         (evcb_callback)(evcb_fd, evcb_res, evcb_arg);
1630 }
1631 
1632 /*
1633   Helper for event_process_active to process all the events in a single queue,
1634   releasing the lock as we go.  This function requires that the lock be held
1635   when it's invoked.  Returns -1 if we get a signal or an event_break that
1636   means we should stop processing any active events now.  Otherwise returns
1637   the number of non-internal event_callbacks that we processed.
1638 */
1639 static int
event_process_active_single_queue(struct event_base * base,struct evcallback_list * activeq,int max_to_process,const struct timeval * endtime)1640 event_process_active_single_queue(struct event_base *base,
1641     struct evcallback_list *activeq,
1642     int max_to_process, const struct timeval *endtime)
1643 {
1644 	struct event_callback *evcb;
1645 	int count = 0;
1646 
1647 	EVUTIL_ASSERT(activeq != NULL);
1648 
1649 	for (evcb = TAILQ_FIRST(activeq); evcb; evcb = TAILQ_FIRST(activeq)) {
1650 		struct event *ev=NULL;
1651 		if (evcb->evcb_flags & EVLIST_INIT) {
1652 			ev = event_callback_to_event(evcb);
1653 
1654 			if (ev->ev_events & EV_PERSIST || ev->ev_flags & EVLIST_FINALIZING)
1655 				event_queue_remove_active(base, evcb);
1656 			else
1657 				event_del_nolock_(ev, EVENT_DEL_NOBLOCK);
1658 			event_debug((
1659 			    "event_process_active: event: %p, %s%s%scall %p",
1660 			    ev,
1661 			    ev->ev_res & EV_READ ? "EV_READ " : " ",
1662 			    ev->ev_res & EV_WRITE ? "EV_WRITE " : " ",
1663 			    ev->ev_res & EV_CLOSED ? "EV_CLOSED " : " ",
1664 			    ev->ev_callback));
1665 		} else {
1666 			event_queue_remove_active(base, evcb);
1667 			event_debug(("event_process_active: event_callback %p, "
1668 				"closure %d, call %p",
1669 				evcb, evcb->evcb_closure, evcb->evcb_cb_union.evcb_callback));
1670 		}
1671 
1672 		if (!(evcb->evcb_flags & EVLIST_INTERNAL))
1673 			++count;
1674 
1675 
1676 		base->current_event = evcb;
1677 #ifndef EVENT__DISABLE_THREAD_SUPPORT
1678 		base->current_event_waiters = 0;
1679 #endif
1680 
1681 		switch (evcb->evcb_closure) {
1682 		case EV_CLOSURE_EVENT_SIGNAL:
1683 			EVUTIL_ASSERT(ev != NULL);
1684 			event_signal_closure(base, ev);
1685 			break;
1686 		case EV_CLOSURE_EVENT_PERSIST:
1687 			EVUTIL_ASSERT(ev != NULL);
1688 			event_persist_closure(base, ev);
1689 			break;
1690 		case EV_CLOSURE_EVENT: {
1691 			void (*evcb_callback)(evutil_socket_t, short, void *);
1692 			short res;
1693 			EVUTIL_ASSERT(ev != NULL);
1694 			evcb_callback = *ev->ev_callback;
1695 			res = ev->ev_res;
1696 			EVBASE_RELEASE_LOCK(base, th_base_lock);
1697 			evcb_callback(ev->ev_fd, res, ev->ev_arg);
1698 		}
1699 		break;
1700 		case EV_CLOSURE_CB_SELF: {
1701 			void (*evcb_selfcb)(struct event_callback *, void *) = evcb->evcb_cb_union.evcb_selfcb;
1702 			EVBASE_RELEASE_LOCK(base, th_base_lock);
1703 			evcb_selfcb(evcb, evcb->evcb_arg);
1704 		}
1705 		break;
1706 		case EV_CLOSURE_EVENT_FINALIZE:
1707 		case EV_CLOSURE_EVENT_FINALIZE_FREE: {
1708 			void (*evcb_evfinalize)(struct event *, void *);
1709 			int evcb_closure = evcb->evcb_closure;
1710 			EVUTIL_ASSERT(ev != NULL);
1711 			base->current_event = NULL;
1712 			evcb_evfinalize = ev->ev_evcallback.evcb_cb_union.evcb_evfinalize;
1713 			EVUTIL_ASSERT((evcb->evcb_flags & EVLIST_FINALIZING));
1714 			EVBASE_RELEASE_LOCK(base, th_base_lock);
1715 			evcb_evfinalize(ev, ev->ev_arg);
1716 			event_debug_note_teardown_(ev);
1717 			if (evcb_closure == EV_CLOSURE_EVENT_FINALIZE_FREE)
1718 				mm_free(ev);
1719 		}
1720 		break;
1721 		case EV_CLOSURE_CB_FINALIZE: {
1722 			void (*evcb_cbfinalize)(struct event_callback *, void *) = evcb->evcb_cb_union.evcb_cbfinalize;
1723 			base->current_event = NULL;
1724 			EVUTIL_ASSERT((evcb->evcb_flags & EVLIST_FINALIZING));
1725 			EVBASE_RELEASE_LOCK(base, th_base_lock);
1726 			evcb_cbfinalize(evcb, evcb->evcb_arg);
1727 		}
1728 		break;
1729 		default:
1730 			EVUTIL_ASSERT(0);
1731 		}
1732 
1733 		EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1734 		base->current_event = NULL;
1735 #ifndef EVENT__DISABLE_THREAD_SUPPORT
1736 		if (base->current_event_waiters) {
1737 			base->current_event_waiters = 0;
1738 			EVTHREAD_COND_BROADCAST(base->current_event_cond);
1739 		}
1740 #endif
1741 
1742 		if (base->event_break)
1743 			return -1;
1744 		if (count >= max_to_process)
1745 			return count;
1746 		if (count && endtime) {
1747 			struct timeval now;
1748 			update_time_cache(base);
1749 			gettime(base, &now);
1750 			if (evutil_timercmp(&now, endtime, >=))
1751 				return count;
1752 		}
1753 		if (base->event_continue)
1754 			break;
1755 	}
1756 	return count;
1757 }
1758 
1759 /*
1760  * Active events are stored in priority queues.  Lower priorities are always
1761  * process before higher priorities.  Low priority events can starve high
1762  * priority ones.
1763  */
1764 
1765 static int
event_process_active(struct event_base * base)1766 event_process_active(struct event_base *base)
1767 {
1768 	/* Caller must hold th_base_lock */
1769 	struct evcallback_list *activeq = NULL;
1770 	int i, c = 0;
1771 	const struct timeval *endtime;
1772 	struct timeval tv;
1773 	const int maxcb = base->max_dispatch_callbacks;
1774 	const int limit_after_prio = base->limit_callbacks_after_prio;
1775 	if (base->max_dispatch_time.tv_sec >= 0) {
1776 		update_time_cache(base);
1777 		gettime(base, &tv);
1778 		evutil_timeradd(&base->max_dispatch_time, &tv, &tv);
1779 		endtime = &tv;
1780 	} else {
1781 		endtime = NULL;
1782 	}
1783 
1784 	for (i = 0; i < base->nactivequeues; ++i) {
1785 		if (TAILQ_FIRST(&base->activequeues[i]) != NULL) {
1786 			base->event_running_priority = i;
1787 			activeq = &base->activequeues[i];
1788 			if (i < limit_after_prio)
1789 				c = event_process_active_single_queue(base, activeq,
1790 				    INT_MAX, NULL);
1791 			else
1792 				c = event_process_active_single_queue(base, activeq,
1793 				    maxcb, endtime);
1794 			if (c < 0) {
1795 				goto done;
1796 			} else if (c > 0)
1797 				break; /* Processed a real event; do not
1798 					* consider lower-priority events */
1799 			/* If we get here, all of the events we processed
1800 			 * were internal.  Continue. */
1801 		}
1802 	}
1803 
1804 done:
1805 	base->event_running_priority = -1;
1806 
1807 	return c;
1808 }
1809 
1810 /*
1811  * Wait continuously for events.  We exit only if no events are left.
1812  */
1813 
1814 int
event_dispatch(void)1815 event_dispatch(void)
1816 {
1817 	return (event_loop(0));
1818 }
1819 
1820 int
event_base_dispatch(struct event_base * event_base)1821 event_base_dispatch(struct event_base *event_base)
1822 {
1823 	return (event_base_loop(event_base, 0));
1824 }
1825 
1826 const char *
event_base_get_method(const struct event_base * base)1827 event_base_get_method(const struct event_base *base)
1828 {
1829 	EVUTIL_ASSERT(base);
1830 	return (base->evsel->name);
1831 }
1832 
1833 /** Callback: used to implement event_base_loopexit by telling the event_base
1834  * that it's time to exit its loop. */
1835 static void
event_loopexit_cb(evutil_socket_t fd,short what,void * arg)1836 event_loopexit_cb(evutil_socket_t fd, short what, void *arg)
1837 {
1838 	struct event_base *base = arg;
1839 	base->event_gotterm = 1;
1840 }
1841 
1842 int
event_loopexit(const struct timeval * tv)1843 event_loopexit(const struct timeval *tv)
1844 {
1845 	return (event_once(-1, EV_TIMEOUT, event_loopexit_cb,
1846 		    current_base, tv));
1847 }
1848 
1849 int
event_base_loopexit(struct event_base * event_base,const struct timeval * tv)1850 event_base_loopexit(struct event_base *event_base, const struct timeval *tv)
1851 {
1852 	return (event_base_once(event_base, -1, EV_TIMEOUT, event_loopexit_cb,
1853 		    event_base, tv));
1854 }
1855 
1856 int
event_loopbreak(void)1857 event_loopbreak(void)
1858 {
1859 	return (event_base_loopbreak(current_base));
1860 }
1861 
1862 int
event_base_loopbreak(struct event_base * event_base)1863 event_base_loopbreak(struct event_base *event_base)
1864 {
1865 	int r = 0;
1866 	if (event_base == NULL)
1867 		return (-1);
1868 
1869 	EVBASE_ACQUIRE_LOCK(event_base, th_base_lock);
1870 	event_base->event_break = 1;
1871 
1872 	if (EVBASE_NEED_NOTIFY(event_base)) {
1873 		r = evthread_notify_base(event_base);
1874 	} else {
1875 		r = (0);
1876 	}
1877 	EVBASE_RELEASE_LOCK(event_base, th_base_lock);
1878 	return r;
1879 }
1880 
1881 int
event_base_loopcontinue(struct event_base * event_base)1882 event_base_loopcontinue(struct event_base *event_base)
1883 {
1884 	int r = 0;
1885 	if (event_base == NULL)
1886 		return (-1);
1887 
1888 	EVBASE_ACQUIRE_LOCK(event_base, th_base_lock);
1889 	event_base->event_continue = 1;
1890 
1891 	if (EVBASE_NEED_NOTIFY(event_base)) {
1892 		r = evthread_notify_base(event_base);
1893 	} else {
1894 		r = (0);
1895 	}
1896 	EVBASE_RELEASE_LOCK(event_base, th_base_lock);
1897 	return r;
1898 }
1899 
1900 int
event_base_got_break(struct event_base * event_base)1901 event_base_got_break(struct event_base *event_base)
1902 {
1903 	int res;
1904 	EVBASE_ACQUIRE_LOCK(event_base, th_base_lock);
1905 	res = event_base->event_break;
1906 	EVBASE_RELEASE_LOCK(event_base, th_base_lock);
1907 	return res;
1908 }
1909 
1910 int
event_base_got_exit(struct event_base * event_base)1911 event_base_got_exit(struct event_base *event_base)
1912 {
1913 	int res;
1914 	EVBASE_ACQUIRE_LOCK(event_base, th_base_lock);
1915 	res = event_base->event_gotterm;
1916 	EVBASE_RELEASE_LOCK(event_base, th_base_lock);
1917 	return res;
1918 }
1919 
1920 /* not thread safe */
1921 
1922 int
event_loop(int flags)1923 event_loop(int flags)
1924 {
1925 	return event_base_loop(current_base, flags);
1926 }
1927 
1928 int
event_base_loop(struct event_base * base,int flags)1929 event_base_loop(struct event_base *base, int flags)
1930 {
1931 	const struct eventop *evsel = base->evsel;
1932 	struct timeval tv;
1933 	struct timeval *tv_p;
1934 	int res, done, retval = 0;
1935 
1936 	/* Grab the lock.  We will release it inside evsel.dispatch, and again
1937 	 * as we invoke user callbacks. */
1938 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
1939 
1940 	if (base->running_loop) {
1941 		event_warnx("%s: reentrant invocation.  Only one event_base_loop"
1942 		    " can run on each event_base at once.", __func__);
1943 		EVBASE_RELEASE_LOCK(base, th_base_lock);
1944 		return -1;
1945 	}
1946 
1947 	base->running_loop = 1;
1948 
1949 	clear_time_cache(base);
1950 
1951 	if (base->sig.ev_signal_added && base->sig.ev_n_signals_added)
1952 		evsig_set_base_(base);
1953 
1954 	done = 0;
1955 
1956 #ifndef EVENT__DISABLE_THREAD_SUPPORT
1957 	base->th_owner_id = EVTHREAD_GET_ID();
1958 #endif
1959 
1960 	base->event_gotterm = base->event_break = 0;
1961 
1962 	while (!done) {
1963 		base->event_continue = 0;
1964 		base->n_deferreds_queued = 0;
1965 
1966 		/* Terminate the loop if we have been asked to */
1967 		if (base->event_gotterm) {
1968 			break;
1969 		}
1970 
1971 		if (base->event_break) {
1972 			break;
1973 		}
1974 
1975 		tv_p = &tv;
1976 		if (!N_ACTIVE_CALLBACKS(base) && !(flags & EVLOOP_NONBLOCK)) {
1977 			timeout_next(base, &tv_p);
1978 		} else {
1979 			/*
1980 			 * if we have active events, we just poll new events
1981 			 * without waiting.
1982 			 */
1983 			evutil_timerclear(&tv);
1984 		}
1985 
1986 		/* If we have no events, we just exit */
1987 		if (0==(flags&EVLOOP_NO_EXIT_ON_EMPTY) &&
1988 		    !event_haveevents(base) && !N_ACTIVE_CALLBACKS(base)) {
1989 			event_debug(("%s: no events registered.", __func__));
1990 			retval = 1;
1991 			goto done;
1992 		}
1993 
1994 		event_queue_make_later_events_active(base);
1995 
1996 		clear_time_cache(base);
1997 
1998 		res = evsel->dispatch(base, tv_p);
1999 
2000 		if (res == -1) {
2001 			event_debug(("%s: dispatch returned unsuccessfully.",
2002 				__func__));
2003 			retval = -1;
2004 			goto done;
2005 		}
2006 
2007 		update_time_cache(base);
2008 
2009 		timeout_process(base);
2010 
2011 		if (N_ACTIVE_CALLBACKS(base)) {
2012 			int n = event_process_active(base);
2013 			if ((flags & EVLOOP_ONCE)
2014 			    && N_ACTIVE_CALLBACKS(base) == 0
2015 			    && n != 0)
2016 				done = 1;
2017 		} else if (flags & EVLOOP_NONBLOCK)
2018 			done = 1;
2019 	}
2020 	event_debug(("%s: asked to terminate loop.", __func__));
2021 
2022 done:
2023 	clear_time_cache(base);
2024 	base->running_loop = 0;
2025 
2026 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2027 
2028 	return (retval);
2029 }
2030 
2031 /* One-time callback to implement event_base_once: invokes the user callback,
2032  * then deletes the allocated storage */
2033 static void
event_once_cb(evutil_socket_t fd,short events,void * arg)2034 event_once_cb(evutil_socket_t fd, short events, void *arg)
2035 {
2036 	struct event_once *eonce = arg;
2037 
2038 	(*eonce->cb)(fd, events, eonce->arg);
2039 	EVBASE_ACQUIRE_LOCK(eonce->ev.ev_base, th_base_lock);
2040 	LIST_REMOVE(eonce, next_once);
2041 	EVBASE_RELEASE_LOCK(eonce->ev.ev_base, th_base_lock);
2042 	event_debug_unassign(&eonce->ev);
2043 	mm_free(eonce);
2044 }
2045 
2046 /* not threadsafe, event scheduled once. */
2047 int
event_once(evutil_socket_t fd,short events,void (* callback)(evutil_socket_t,short,void *),void * arg,const struct timeval * tv)2048 event_once(evutil_socket_t fd, short events,
2049     void (*callback)(evutil_socket_t, short, void *),
2050     void *arg, const struct timeval *tv)
2051 {
2052 	return event_base_once(current_base, fd, events, callback, arg, tv);
2053 }
2054 
2055 /* Schedules an event once */
2056 int
event_base_once(struct event_base * base,evutil_socket_t fd,short events,void (* callback)(evutil_socket_t,short,void *),void * arg,const struct timeval * tv)2057 event_base_once(struct event_base *base, evutil_socket_t fd, short events,
2058     void (*callback)(evutil_socket_t, short, void *),
2059     void *arg, const struct timeval *tv)
2060 {
2061 	struct event_once *eonce;
2062 	int res = 0;
2063 	int activate = 0;
2064 
2065 	/* We cannot support signals that just fire once, or persistent
2066 	 * events. */
2067 	if (events & (EV_SIGNAL|EV_PERSIST))
2068 		return (-1);
2069 
2070 	if ((eonce = mm_calloc(1, sizeof(struct event_once))) == NULL)
2071 		return (-1);
2072 
2073 	eonce->cb = callback;
2074 	eonce->arg = arg;
2075 
2076 	if ((events & (EV_TIMEOUT|EV_SIGNAL|EV_READ|EV_WRITE|EV_CLOSED)) == EV_TIMEOUT) {
2077 		evtimer_assign(&eonce->ev, base, event_once_cb, eonce);
2078 
2079 		if (tv == NULL || ! evutil_timerisset(tv)) {
2080 			/* If the event is going to become active immediately,
2081 			 * don't put it on the timeout queue.  This is one
2082 			 * idiom for scheduling a callback, so let's make
2083 			 * it fast (and order-preserving). */
2084 			activate = 1;
2085 		}
2086 	} else if (events & (EV_READ|EV_WRITE|EV_CLOSED)) {
2087 		events &= EV_READ|EV_WRITE|EV_CLOSED;
2088 
2089 		event_assign(&eonce->ev, base, fd, events, event_once_cb, eonce);
2090 	} else {
2091 		/* Bad event combination */
2092 		mm_free(eonce);
2093 		return (-1);
2094 	}
2095 
2096 	if (res == 0) {
2097 		EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2098 		if (activate)
2099 			event_active_nolock_(&eonce->ev, EV_TIMEOUT, 1);
2100 		else
2101 			res = event_add_nolock_(&eonce->ev, tv, 0);
2102 
2103 		if (res != 0) {
2104 			mm_free(eonce);
2105 			return (res);
2106 		} else {
2107 			LIST_INSERT_HEAD(&base->once_events, eonce, next_once);
2108 		}
2109 		EVBASE_RELEASE_LOCK(base, th_base_lock);
2110 	}
2111 
2112 	return (0);
2113 }
2114 
2115 int
event_assign(struct event * ev,struct event_base * base,evutil_socket_t fd,short events,void (* callback)(evutil_socket_t,short,void *),void * arg)2116 event_assign(struct event *ev, struct event_base *base, evutil_socket_t fd, short events, void (*callback)(evutil_socket_t, short, void *), void *arg)
2117 {
2118 	if (!base)
2119 		base = current_base;
2120 	if (arg == &event_self_cbarg_ptr_)
2121 		arg = ev;
2122 
2123 	if (!(events & EV_SIGNAL))
2124 		event_debug_assert_socket_nonblocking_(fd);
2125 	event_debug_assert_not_added_(ev);
2126 
2127 	ev->ev_base = base;
2128 
2129 	ev->ev_callback = callback;
2130 	ev->ev_arg = arg;
2131 	ev->ev_fd = fd;
2132 	ev->ev_events = events;
2133 	ev->ev_res = 0;
2134 	ev->ev_flags = EVLIST_INIT;
2135 	ev->ev_ncalls = 0;
2136 	ev->ev_pncalls = NULL;
2137 
2138 	if (events & EV_SIGNAL) {
2139 		if ((events & (EV_READ|EV_WRITE|EV_CLOSED)) != 0) {
2140 			event_warnx("%s: EV_SIGNAL is not compatible with "
2141 			    "EV_READ, EV_WRITE or EV_CLOSED", __func__);
2142 			return -1;
2143 		}
2144 		ev->ev_closure = EV_CLOSURE_EVENT_SIGNAL;
2145 	} else {
2146 		if (events & EV_PERSIST) {
2147 			evutil_timerclear(&ev->ev_io_timeout);
2148 			ev->ev_closure = EV_CLOSURE_EVENT_PERSIST;
2149 		} else {
2150 			ev->ev_closure = EV_CLOSURE_EVENT;
2151 		}
2152 	}
2153 
2154 	min_heap_elem_init_(ev);
2155 
2156 	if (base != NULL) {
2157 		/* by default, we put new events into the middle priority */
2158 		ev->ev_pri = base->nactivequeues / 2;
2159 	}
2160 
2161 	event_debug_note_setup_(ev);
2162 
2163 	return 0;
2164 }
2165 
2166 int
event_base_set(struct event_base * base,struct event * ev)2167 event_base_set(struct event_base *base, struct event *ev)
2168 {
2169 	/* Only innocent events may be assigned to a different base */
2170 	if (ev->ev_flags != EVLIST_INIT)
2171 		return (-1);
2172 
2173 	event_debug_assert_is_setup_(ev);
2174 
2175 	ev->ev_base = base;
2176 	ev->ev_pri = base->nactivequeues/2;
2177 
2178 	return (0);
2179 }
2180 
2181 void
event_set(struct event * ev,evutil_socket_t fd,short events,void (* callback)(evutil_socket_t,short,void *),void * arg)2182 event_set(struct event *ev, evutil_socket_t fd, short events,
2183 	  void (*callback)(evutil_socket_t, short, void *), void *arg)
2184 {
2185 	int r;
2186 	r = event_assign(ev, current_base, fd, events, callback, arg);
2187 	EVUTIL_ASSERT(r == 0);
2188 }
2189 
2190 void *
event_self_cbarg(void)2191 event_self_cbarg(void)
2192 {
2193 	return &event_self_cbarg_ptr_;
2194 }
2195 
2196 struct event *
event_base_get_running_event(struct event_base * base)2197 event_base_get_running_event(struct event_base *base)
2198 {
2199 	struct event *ev = NULL;
2200 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2201 	if (EVBASE_IN_THREAD(base)) {
2202 		struct event_callback *evcb = base->current_event;
2203 		if (evcb->evcb_flags & EVLIST_INIT)
2204 			ev = event_callback_to_event(evcb);
2205 	}
2206 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2207 	return ev;
2208 }
2209 
2210 struct event *
event_new(struct event_base * base,evutil_socket_t fd,short events,void (* cb)(evutil_socket_t,short,void *),void * arg)2211 event_new(struct event_base *base, evutil_socket_t fd, short events, void (*cb)(evutil_socket_t, short, void *), void *arg)
2212 {
2213 	struct event *ev;
2214 	ev = mm_malloc(sizeof(struct event));
2215 	if (ev == NULL)
2216 		return (NULL);
2217 	if (event_assign(ev, base, fd, events, cb, arg) < 0) {
2218 		mm_free(ev);
2219 		return (NULL);
2220 	}
2221 
2222 	return (ev);
2223 }
2224 
2225 void
event_free(struct event * ev)2226 event_free(struct event *ev)
2227 {
2228 	/* This is disabled, so that events which have been finalized be a
2229 	 * valid target for event_free(). That's */
2230 	// event_debug_assert_is_setup_(ev);
2231 
2232 	/* make sure that this event won't be coming back to haunt us. */
2233 	event_del(ev);
2234 	event_debug_note_teardown_(ev);
2235 	mm_free(ev);
2236 
2237 }
2238 
2239 void
event_debug_unassign(struct event * ev)2240 event_debug_unassign(struct event *ev)
2241 {
2242 	event_debug_assert_not_added_(ev);
2243 	event_debug_note_teardown_(ev);
2244 
2245 	ev->ev_flags &= ~EVLIST_INIT;
2246 }
2247 
2248 #define EVENT_FINALIZE_FREE_ 0x10000
2249 static int
event_finalize_nolock_(struct event_base * base,unsigned flags,struct event * ev,event_finalize_callback_fn cb)2250 event_finalize_nolock_(struct event_base *base, unsigned flags, struct event *ev, event_finalize_callback_fn cb)
2251 {
2252 	ev_uint8_t closure = (flags & EVENT_FINALIZE_FREE_) ?
2253 	    EV_CLOSURE_EVENT_FINALIZE_FREE : EV_CLOSURE_EVENT_FINALIZE;
2254 
2255 	event_del_nolock_(ev, EVENT_DEL_NOBLOCK);
2256 	ev->ev_closure = closure;
2257 	ev->ev_evcallback.evcb_cb_union.evcb_evfinalize = cb;
2258 	event_active_nolock_(ev, EV_FINALIZE, 1);
2259 	ev->ev_flags |= EVLIST_FINALIZING;
2260 	return 0;
2261 }
2262 
2263 static int
event_finalize_impl_(unsigned flags,struct event * ev,event_finalize_callback_fn cb)2264 event_finalize_impl_(unsigned flags, struct event *ev, event_finalize_callback_fn cb)
2265 {
2266 	int r;
2267 	struct event_base *base = ev->ev_base;
2268 	if (EVUTIL_FAILURE_CHECK(!base)) {
2269 		event_warnx("%s: event has no event_base set.", __func__);
2270 		return -1;
2271 	}
2272 
2273 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2274 	r = event_finalize_nolock_(base, flags, ev, cb);
2275 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2276 	return r;
2277 }
2278 
2279 int
event_finalize(unsigned flags,struct event * ev,event_finalize_callback_fn cb)2280 event_finalize(unsigned flags, struct event *ev, event_finalize_callback_fn cb)
2281 {
2282 	return event_finalize_impl_(flags, ev, cb);
2283 }
2284 
2285 int
event_free_finalize(unsigned flags,struct event * ev,event_finalize_callback_fn cb)2286 event_free_finalize(unsigned flags, struct event *ev, event_finalize_callback_fn cb)
2287 {
2288 	return event_finalize_impl_(flags|EVENT_FINALIZE_FREE_, ev, cb);
2289 }
2290 
2291 void
event_callback_finalize_nolock_(struct event_base * base,unsigned flags,struct event_callback * evcb,void (* cb)(struct event_callback *,void *))2292 event_callback_finalize_nolock_(struct event_base *base, unsigned flags, struct event_callback *evcb, void (*cb)(struct event_callback *, void *))
2293 {
2294 	struct event *ev = NULL;
2295 	if (evcb->evcb_flags & EVLIST_INIT) {
2296 		ev = event_callback_to_event(evcb);
2297 		event_del_nolock_(ev, EVENT_DEL_NOBLOCK);
2298 	} else {
2299 		event_callback_cancel_nolock_(base, evcb, 0); /*XXX can this fail?*/
2300 	}
2301 
2302 	evcb->evcb_closure = EV_CLOSURE_CB_FINALIZE;
2303 	evcb->evcb_cb_union.evcb_cbfinalize = cb;
2304 	event_callback_activate_nolock_(base, evcb); /* XXX can this really fail?*/
2305 	evcb->evcb_flags |= EVLIST_FINALIZING;
2306 }
2307 
2308 void
event_callback_finalize_(struct event_base * base,unsigned flags,struct event_callback * evcb,void (* cb)(struct event_callback *,void *))2309 event_callback_finalize_(struct event_base *base, unsigned flags, struct event_callback *evcb, void (*cb)(struct event_callback *, void *))
2310 {
2311 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2312 	event_callback_finalize_nolock_(base, flags, evcb, cb);
2313 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2314 }
2315 
2316 /** Internal: Finalize all of the n_cbs callbacks in evcbs.  The provided
2317  * callback will be invoked on *one of them*, after they have *all* been
2318  * finalized. */
2319 int
event_callback_finalize_many_(struct event_base * base,int n_cbs,struct event_callback ** evcbs,void (* cb)(struct event_callback *,void *))2320 event_callback_finalize_many_(struct event_base *base, int n_cbs, struct event_callback **evcbs, void (*cb)(struct event_callback *, void *))
2321 {
2322 	int n_pending = 0, i;
2323 
2324 	if (base == NULL)
2325 		base = current_base;
2326 
2327 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2328 
2329 	event_debug(("%s: %d events finalizing", __func__, n_cbs));
2330 
2331 	/* At most one can be currently executing; the rest we just
2332 	 * cancel... But we always make sure that the finalize callback
2333 	 * runs. */
2334 	for (i = 0; i < n_cbs; ++i) {
2335 		struct event_callback *evcb = evcbs[i];
2336 		if (evcb == base->current_event) {
2337 			event_callback_finalize_nolock_(base, 0, evcb, cb);
2338 			++n_pending;
2339 		} else {
2340 			event_callback_cancel_nolock_(base, evcb, 0);
2341 		}
2342 	}
2343 
2344 	if (n_pending == 0) {
2345 		/* Just do the first one. */
2346 		event_callback_finalize_nolock_(base, 0, evcbs[0], cb);
2347 	}
2348 
2349 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2350 	return 0;
2351 }
2352 
2353 /*
2354  * Set's the priority of an event - if an event is already scheduled
2355  * changing the priority is going to fail.
2356  */
2357 
2358 int
event_priority_set(struct event * ev,int pri)2359 event_priority_set(struct event *ev, int pri)
2360 {
2361 	event_debug_assert_is_setup_(ev);
2362 
2363 	if (ev->ev_flags & EVLIST_ACTIVE)
2364 		return (-1);
2365 	if (pri < 0 || pri >= ev->ev_base->nactivequeues)
2366 		return (-1);
2367 
2368 	ev->ev_pri = pri;
2369 
2370 	return (0);
2371 }
2372 
2373 /*
2374  * Checks if a specific event is pending or scheduled.
2375  */
2376 
2377 int
event_pending(const struct event * ev,short event,struct timeval * tv)2378 event_pending(const struct event *ev, short event, struct timeval *tv)
2379 {
2380 	int flags = 0;
2381 
2382 	if (EVUTIL_FAILURE_CHECK(ev->ev_base == NULL)) {
2383 		event_warnx("%s: event has no event_base set.", __func__);
2384 		return 0;
2385 	}
2386 
2387 	EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock);
2388 	event_debug_assert_is_setup_(ev);
2389 
2390 	if (ev->ev_flags & EVLIST_INSERTED)
2391 		flags |= (ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED|EV_SIGNAL));
2392 	if (ev->ev_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER))
2393 		flags |= ev->ev_res;
2394 	if (ev->ev_flags & EVLIST_TIMEOUT)
2395 		flags |= EV_TIMEOUT;
2396 
2397 	event &= (EV_TIMEOUT|EV_READ|EV_WRITE|EV_CLOSED|EV_SIGNAL);
2398 
2399 	/* See if there is a timeout that we should report */
2400 	if (tv != NULL && (flags & event & EV_TIMEOUT)) {
2401 		struct timeval tmp = ev->ev_timeout;
2402 		tmp.tv_usec &= MICROSECONDS_MASK;
2403 		/* correctly remamp to real time */
2404 		evutil_timeradd(&ev->ev_base->tv_clock_diff, &tmp, tv);
2405 	}
2406 
2407 	EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock);
2408 
2409 	return (flags & event);
2410 }
2411 
2412 int
event_initialized(const struct event * ev)2413 event_initialized(const struct event *ev)
2414 {
2415 	if (!(ev->ev_flags & EVLIST_INIT))
2416 		return 0;
2417 
2418 	return 1;
2419 }
2420 
2421 void
event_get_assignment(const struct event * event,struct event_base ** base_out,evutil_socket_t * fd_out,short * events_out,event_callback_fn * callback_out,void ** arg_out)2422 event_get_assignment(const struct event *event, struct event_base **base_out, evutil_socket_t *fd_out, short *events_out, event_callback_fn *callback_out, void **arg_out)
2423 {
2424 	event_debug_assert_is_setup_(event);
2425 
2426 	if (base_out)
2427 		*base_out = event->ev_base;
2428 	if (fd_out)
2429 		*fd_out = event->ev_fd;
2430 	if (events_out)
2431 		*events_out = event->ev_events;
2432 	if (callback_out)
2433 		*callback_out = event->ev_callback;
2434 	if (arg_out)
2435 		*arg_out = event->ev_arg;
2436 }
2437 
2438 size_t
event_get_struct_event_size(void)2439 event_get_struct_event_size(void)
2440 {
2441 	return sizeof(struct event);
2442 }
2443 
2444 evutil_socket_t
event_get_fd(const struct event * ev)2445 event_get_fd(const struct event *ev)
2446 {
2447 	event_debug_assert_is_setup_(ev);
2448 	return ev->ev_fd;
2449 }
2450 
2451 struct event_base *
event_get_base(const struct event * ev)2452 event_get_base(const struct event *ev)
2453 {
2454 	event_debug_assert_is_setup_(ev);
2455 	return ev->ev_base;
2456 }
2457 
2458 short
event_get_events(const struct event * ev)2459 event_get_events(const struct event *ev)
2460 {
2461 	event_debug_assert_is_setup_(ev);
2462 	return ev->ev_events;
2463 }
2464 
2465 event_callback_fn
event_get_callback(const struct event * ev)2466 event_get_callback(const struct event *ev)
2467 {
2468 	event_debug_assert_is_setup_(ev);
2469 	return ev->ev_callback;
2470 }
2471 
2472 void *
event_get_callback_arg(const struct event * ev)2473 event_get_callback_arg(const struct event *ev)
2474 {
2475 	event_debug_assert_is_setup_(ev);
2476 	return ev->ev_arg;
2477 }
2478 
2479 int
event_get_priority(const struct event * ev)2480 event_get_priority(const struct event *ev)
2481 {
2482 	event_debug_assert_is_setup_(ev);
2483 	return ev->ev_pri;
2484 }
2485 
2486 int
event_add(struct event * ev,const struct timeval * tv)2487 event_add(struct event *ev, const struct timeval *tv)
2488 {
2489 	int res;
2490 
2491 	if (EVUTIL_FAILURE_CHECK(!ev->ev_base)) {
2492 		event_warnx("%s: event has no event_base set.", __func__);
2493 		return -1;
2494 	}
2495 
2496 	EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock);
2497 
2498 	res = event_add_nolock_(ev, tv, 0);
2499 
2500 	EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock);
2501 
2502 	return (res);
2503 }
2504 
2505 /* Helper callback: wake an event_base from another thread.  This version
2506  * works by writing a byte to one end of a socketpair, so that the event_base
2507  * listening on the other end will wake up as the corresponding event
2508  * triggers */
2509 static int
evthread_notify_base_default(struct event_base * base)2510 evthread_notify_base_default(struct event_base *base)
2511 {
2512 	char buf[1];
2513 	int r;
2514 	buf[0] = (char) 0;
2515 #ifdef _WIN32
2516 	r = send(base->th_notify_fd[1], buf, 1, 0);
2517 #else
2518 	r = write(base->th_notify_fd[1], buf, 1);
2519 #endif
2520 	return (r < 0 && ! EVUTIL_ERR_IS_EAGAIN(errno)) ? -1 : 0;
2521 }
2522 
2523 #ifdef EVENT__HAVE_EVENTFD
2524 /* Helper callback: wake an event_base from another thread.  This version
2525  * assumes that you have a working eventfd() implementation. */
2526 static int
evthread_notify_base_eventfd(struct event_base * base)2527 evthread_notify_base_eventfd(struct event_base *base)
2528 {
2529 	ev_uint64_t msg = 1;
2530 	int r;
2531 	do {
2532 		r = write(base->th_notify_fd[0], (void*) &msg, sizeof(msg));
2533 	} while (r < 0 && errno == EAGAIN);
2534 
2535 	return (r < 0) ? -1 : 0;
2536 }
2537 #endif
2538 
2539 
2540 /** Tell the thread currently running the event_loop for base (if any) that it
2541  * needs to stop waiting in its dispatch function (if it is) and process all
2542  * active callbacks. */
2543 static int
evthread_notify_base(struct event_base * base)2544 evthread_notify_base(struct event_base *base)
2545 {
2546 	EVENT_BASE_ASSERT_LOCKED(base);
2547 	if (!base->th_notify_fn)
2548 		return -1;
2549 	if (base->is_notify_pending)
2550 		return 0;
2551 	base->is_notify_pending = 1;
2552 	return base->th_notify_fn(base);
2553 }
2554 
2555 /* Implementation function to remove a timeout on a currently pending event.
2556  */
2557 int
event_remove_timer_nolock_(struct event * ev)2558 event_remove_timer_nolock_(struct event *ev)
2559 {
2560 	struct event_base *base = ev->ev_base;
2561 
2562 	EVENT_BASE_ASSERT_LOCKED(base);
2563 	event_debug_assert_is_setup_(ev);
2564 
2565 	event_debug(("event_remove_timer_nolock: event: %p", ev));
2566 
2567 	/* If it's not pending on a timeout, we don't need to do anything. */
2568 	if (ev->ev_flags & EVLIST_TIMEOUT) {
2569 		event_queue_remove_timeout(base, ev);
2570 		evutil_timerclear(&ev->ev_.ev_io.ev_timeout);
2571 	}
2572 
2573 	return (0);
2574 }
2575 
2576 int
event_remove_timer(struct event * ev)2577 event_remove_timer(struct event *ev)
2578 {
2579 	int res;
2580 
2581 	if (EVUTIL_FAILURE_CHECK(!ev->ev_base)) {
2582 		event_warnx("%s: event has no event_base set.", __func__);
2583 		return -1;
2584 	}
2585 
2586 	EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock);
2587 
2588 	res = event_remove_timer_nolock_(ev);
2589 
2590 	EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock);
2591 
2592 	return (res);
2593 }
2594 
2595 /* Implementation function to add an event.  Works just like event_add,
2596  * except: 1) it requires that we have the lock.  2) if tv_is_absolute is set,
2597  * we treat tv as an absolute time, not as an interval to add to the current
2598  * time */
2599 int
event_add_nolock_(struct event * ev,const struct timeval * tv,int tv_is_absolute)2600 event_add_nolock_(struct event *ev, const struct timeval *tv,
2601     int tv_is_absolute)
2602 {
2603 	struct event_base *base = ev->ev_base;
2604 	int res = 0;
2605 	int notify = 0;
2606 
2607 	EVENT_BASE_ASSERT_LOCKED(base);
2608 	event_debug_assert_is_setup_(ev);
2609 
2610 	event_debug((
2611 		 "event_add: event: %p (fd "EV_SOCK_FMT"), %s%s%s%scall %p",
2612 		 ev,
2613 		 EV_SOCK_ARG(ev->ev_fd),
2614 		 ev->ev_events & EV_READ ? "EV_READ " : " ",
2615 		 ev->ev_events & EV_WRITE ? "EV_WRITE " : " ",
2616 		 ev->ev_events & EV_CLOSED ? "EV_CLOSED " : " ",
2617 		 tv ? "EV_TIMEOUT " : " ",
2618 		 ev->ev_callback));
2619 
2620 	EVUTIL_ASSERT(!(ev->ev_flags & ~EVLIST_ALL));
2621 
2622 	if (ev->ev_flags & EVLIST_FINALIZING) {
2623 		/* XXXX debug */
2624 		return (-1);
2625 	}
2626 
2627 	/*
2628 	 * prepare for timeout insertion further below, if we get a
2629 	 * failure on any step, we should not change any state.
2630 	 */
2631 	if (tv != NULL && !(ev->ev_flags & EVLIST_TIMEOUT)) {
2632 		if (min_heap_reserve_(&base->timeheap,
2633 			1 + min_heap_size_(&base->timeheap)) == -1)
2634 			return (-1);  /* ENOMEM == errno */
2635 	}
2636 
2637 	/* If the main thread is currently executing a signal event's
2638 	 * callback, and we are not the main thread, then we want to wait
2639 	 * until the callback is done before we mess with the event, or else
2640 	 * we can race on ev_ncalls and ev_pncalls below. */
2641 #ifndef EVENT__DISABLE_THREAD_SUPPORT
2642 	if (base->current_event == event_to_event_callback(ev) &&
2643 	    (ev->ev_events & EV_SIGNAL)
2644 	    && !EVBASE_IN_THREAD(base)) {
2645 		++base->current_event_waiters;
2646 		EVTHREAD_COND_WAIT(base->current_event_cond, base->th_base_lock);
2647 	}
2648 #endif
2649 
2650 	if ((ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED|EV_SIGNAL)) &&
2651 	    !(ev->ev_flags & (EVLIST_INSERTED|EVLIST_ACTIVE|EVLIST_ACTIVE_LATER))) {
2652 		if (ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED))
2653 			res = evmap_io_add_(base, ev->ev_fd, ev);
2654 		else if (ev->ev_events & EV_SIGNAL)
2655 			res = evmap_signal_add_(base, (int)ev->ev_fd, ev);
2656 		if (res != -1)
2657 			event_queue_insert_inserted(base, ev);
2658 		if (res == 1) {
2659 			/* evmap says we need to notify the main thread. */
2660 			notify = 1;
2661 			res = 0;
2662 		}
2663 	}
2664 
2665 	/*
2666 	 * we should change the timeout state only if the previous event
2667 	 * addition succeeded.
2668 	 */
2669 	if (res != -1 && tv != NULL) {
2670 		struct timeval now;
2671 		int common_timeout;
2672 #ifdef USE_REINSERT_TIMEOUT
2673 		int was_common;
2674 		int old_timeout_idx;
2675 #endif
2676 
2677 		/*
2678 		 * for persistent timeout events, we remember the
2679 		 * timeout value and re-add the event.
2680 		 *
2681 		 * If tv_is_absolute, this was already set.
2682 		 */
2683 		if (ev->ev_closure == EV_CLOSURE_EVENT_PERSIST && !tv_is_absolute)
2684 			ev->ev_io_timeout = *tv;
2685 
2686 #ifndef USE_REINSERT_TIMEOUT
2687 		if (ev->ev_flags & EVLIST_TIMEOUT) {
2688 			event_queue_remove_timeout(base, ev);
2689 		}
2690 #endif
2691 
2692 		/* Check if it is active due to a timeout.  Rescheduling
2693 		 * this timeout before the callback can be executed
2694 		 * removes it from the active list. */
2695 		if ((ev->ev_flags & EVLIST_ACTIVE) &&
2696 		    (ev->ev_res & EV_TIMEOUT)) {
2697 			if (ev->ev_events & EV_SIGNAL) {
2698 				/* See if we are just active executing
2699 				 * this event in a loop
2700 				 */
2701 				if (ev->ev_ncalls && ev->ev_pncalls) {
2702 					/* Abort loop */
2703 					*ev->ev_pncalls = 0;
2704 				}
2705 			}
2706 
2707 			event_queue_remove_active(base, event_to_event_callback(ev));
2708 		}
2709 
2710 		gettime(base, &now);
2711 
2712 		common_timeout = is_common_timeout(tv, base);
2713 #ifdef USE_REINSERT_TIMEOUT
2714 		was_common = is_common_timeout(&ev->ev_timeout, base);
2715 		old_timeout_idx = COMMON_TIMEOUT_IDX(&ev->ev_timeout);
2716 #endif
2717 
2718 		if (tv_is_absolute) {
2719 			ev->ev_timeout = *tv;
2720 		} else if (common_timeout) {
2721 			struct timeval tmp = *tv;
2722 			tmp.tv_usec &= MICROSECONDS_MASK;
2723 			evutil_timeradd(&now, &tmp, &ev->ev_timeout);
2724 			ev->ev_timeout.tv_usec |=
2725 			    (tv->tv_usec & ~MICROSECONDS_MASK);
2726 		} else {
2727 			evutil_timeradd(&now, tv, &ev->ev_timeout);
2728 		}
2729 
2730 		event_debug((
2731 			 "event_add: event %p, timeout in %d seconds %d useconds, call %p",
2732 			 ev, (int)tv->tv_sec, (int)tv->tv_usec, ev->ev_callback));
2733 
2734 #ifdef USE_REINSERT_TIMEOUT
2735 		event_queue_reinsert_timeout(base, ev, was_common, common_timeout, old_timeout_idx);
2736 #else
2737 		event_queue_insert_timeout(base, ev);
2738 #endif
2739 
2740 		if (common_timeout) {
2741 			struct common_timeout_list *ctl =
2742 			    get_common_timeout_list(base, &ev->ev_timeout);
2743 			if (ev == TAILQ_FIRST(&ctl->events)) {
2744 				common_timeout_schedule(ctl, &now, ev);
2745 			}
2746 		} else {
2747 			struct event* top = NULL;
2748 			/* See if the earliest timeout is now earlier than it
2749 			 * was before: if so, we will need to tell the main
2750 			 * thread to wake up earlier than it would otherwise.
2751 			 * We double check the timeout of the top element to
2752 			 * handle time distortions due to system suspension.
2753 			 */
2754 			if (min_heap_elt_is_top_(ev))
2755 				notify = 1;
2756 			else if ((top = min_heap_top_(&base->timeheap)) != NULL &&
2757 					 evutil_timercmp(&top->ev_timeout, &now, <))
2758 				notify = 1;
2759 		}
2760 	}
2761 
2762 	/* if we are not in the right thread, we need to wake up the loop */
2763 	if (res != -1 && notify && EVBASE_NEED_NOTIFY(base))
2764 		evthread_notify_base(base);
2765 
2766 	event_debug_note_add_(ev);
2767 
2768 	return (res);
2769 }
2770 
2771 static int
event_del_(struct event * ev,int blocking)2772 event_del_(struct event *ev, int blocking)
2773 {
2774 	int res;
2775 	struct event_base *base = ev->ev_base;
2776 
2777 	if (EVUTIL_FAILURE_CHECK(!base)) {
2778 		event_warnx("%s: event has no event_base set.", __func__);
2779 		return -1;
2780 	}
2781 
2782 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
2783 	res = event_del_nolock_(ev, blocking);
2784 	EVBASE_RELEASE_LOCK(base, th_base_lock);
2785 
2786 	return (res);
2787 }
2788 
2789 int
event_del(struct event * ev)2790 event_del(struct event *ev)
2791 {
2792 	return event_del_(ev, EVENT_DEL_AUTOBLOCK);
2793 }
2794 
2795 int
event_del_block(struct event * ev)2796 event_del_block(struct event *ev)
2797 {
2798 	return event_del_(ev, EVENT_DEL_BLOCK);
2799 }
2800 
2801 int
event_del_noblock(struct event * ev)2802 event_del_noblock(struct event *ev)
2803 {
2804 	return event_del_(ev, EVENT_DEL_NOBLOCK);
2805 }
2806 
2807 /** Helper for event_del: always called with th_base_lock held.
2808  *
2809  * "blocking" must be one of the EVENT_DEL_{BLOCK, NOBLOCK, AUTOBLOCK,
2810  * EVEN_IF_FINALIZING} values. See those for more information.
2811  */
2812 int
event_del_nolock_(struct event * ev,int blocking)2813 event_del_nolock_(struct event *ev, int blocking)
2814 {
2815 	struct event_base *base;
2816 	int res = 0, notify = 0;
2817 
2818 	event_debug(("event_del: %p (fd "EV_SOCK_FMT"), callback %p",
2819 		ev, EV_SOCK_ARG(ev->ev_fd), ev->ev_callback));
2820 
2821 	/* An event without a base has not been added */
2822 	if (ev->ev_base == NULL)
2823 		return (-1);
2824 
2825 	EVENT_BASE_ASSERT_LOCKED(ev->ev_base);
2826 
2827 	if (blocking != EVENT_DEL_EVEN_IF_FINALIZING) {
2828 		if (ev->ev_flags & EVLIST_FINALIZING) {
2829 			/* XXXX Debug */
2830 			return 0;
2831 		}
2832 	}
2833 
2834 	base = ev->ev_base;
2835 
2836 	EVUTIL_ASSERT(!(ev->ev_flags & ~EVLIST_ALL));
2837 
2838 	/* See if we are just active executing this event in a loop */
2839 	if (ev->ev_events & EV_SIGNAL) {
2840 		if (ev->ev_ncalls && ev->ev_pncalls) {
2841 			/* Abort loop */
2842 			*ev->ev_pncalls = 0;
2843 		}
2844 	}
2845 
2846 	if (ev->ev_flags & EVLIST_TIMEOUT) {
2847 		/* NOTE: We never need to notify the main thread because of a
2848 		 * deleted timeout event: all that could happen if we don't is
2849 		 * that the dispatch loop might wake up too early.  But the
2850 		 * point of notifying the main thread _is_ to wake up the
2851 		 * dispatch loop early anyway, so we wouldn't gain anything by
2852 		 * doing it.
2853 		 */
2854 		event_queue_remove_timeout(base, ev);
2855 	}
2856 
2857 	if (ev->ev_flags & EVLIST_ACTIVE)
2858 		event_queue_remove_active(base, event_to_event_callback(ev));
2859 	else if (ev->ev_flags & EVLIST_ACTIVE_LATER)
2860 		event_queue_remove_active_later(base, event_to_event_callback(ev));
2861 
2862 	if (ev->ev_flags & EVLIST_INSERTED) {
2863 		event_queue_remove_inserted(base, ev);
2864 		if (ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED))
2865 			res = evmap_io_del_(base, ev->ev_fd, ev);
2866 		else
2867 			res = evmap_signal_del_(base, (int)ev->ev_fd, ev);
2868 		if (res == 1) {
2869 			/* evmap says we need to notify the main thread. */
2870 			notify = 1;
2871 			res = 0;
2872 		}
2873 		/* If we do not have events, let's notify event base so it can
2874 		 * exit without waiting */
2875 		if (!event_haveevents(base) && !N_ACTIVE_CALLBACKS(base))
2876 			notify = 1;
2877 	}
2878 
2879 	/* if we are not in the right thread, we need to wake up the loop */
2880 	if (res != -1 && notify && EVBASE_NEED_NOTIFY(base))
2881 		evthread_notify_base(base);
2882 
2883 	event_debug_note_del_(ev);
2884 
2885 	/* If the main thread is currently executing this event's callback,
2886 	 * and we are not the main thread, then we want to wait until the
2887 	 * callback is done before returning. That way, when this function
2888 	 * returns, it will be safe to free the user-supplied argument.
2889 	 */
2890 #ifndef EVENT__DISABLE_THREAD_SUPPORT
2891 	if (blocking != EVENT_DEL_NOBLOCK &&
2892 	    base->current_event == event_to_event_callback(ev) &&
2893 	    !EVBASE_IN_THREAD(base) &&
2894 	    (blocking == EVENT_DEL_BLOCK || !(ev->ev_events & EV_FINALIZE))) {
2895 		++base->current_event_waiters;
2896 		EVTHREAD_COND_WAIT(base->current_event_cond, base->th_base_lock);
2897 	}
2898 #endif
2899 
2900 	return (res);
2901 }
2902 
2903 void
event_active(struct event * ev,int res,short ncalls)2904 event_active(struct event *ev, int res, short ncalls)
2905 {
2906 	if (EVUTIL_FAILURE_CHECK(!ev->ev_base)) {
2907 		event_warnx("%s: event has no event_base set.", __func__);
2908 		return;
2909 	}
2910 
2911 	EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock);
2912 
2913 	event_debug_assert_is_setup_(ev);
2914 
2915 	event_active_nolock_(ev, res, ncalls);
2916 
2917 	EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock);
2918 }
2919 
2920 
2921 void
event_active_nolock_(struct event * ev,int res,short ncalls)2922 event_active_nolock_(struct event *ev, int res, short ncalls)
2923 {
2924 	struct event_base *base;
2925 
2926 	event_debug(("event_active: %p (fd "EV_SOCK_FMT"), res %d, callback %p",
2927 		ev, EV_SOCK_ARG(ev->ev_fd), (int)res, ev->ev_callback));
2928 
2929 	base = ev->ev_base;
2930 	EVENT_BASE_ASSERT_LOCKED(base);
2931 
2932 	if (ev->ev_flags & EVLIST_FINALIZING) {
2933 		/* XXXX debug */
2934 		return;
2935 	}
2936 
2937 	switch ((ev->ev_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER))) {
2938 	default:
2939 	case EVLIST_ACTIVE|EVLIST_ACTIVE_LATER:
2940 		EVUTIL_ASSERT(0);
2941 		break;
2942 	case EVLIST_ACTIVE:
2943 		/* We get different kinds of events, add them together */
2944 		ev->ev_res |= res;
2945 		return;
2946 	case EVLIST_ACTIVE_LATER:
2947 		ev->ev_res |= res;
2948 		break;
2949 	case 0:
2950 		ev->ev_res = res;
2951 		break;
2952 	}
2953 
2954 	if (ev->ev_pri < base->event_running_priority)
2955 		base->event_continue = 1;
2956 
2957 	if (ev->ev_events & EV_SIGNAL) {
2958 #ifndef EVENT__DISABLE_THREAD_SUPPORT
2959 		if (base->current_event == event_to_event_callback(ev) &&
2960 		    !EVBASE_IN_THREAD(base)) {
2961 			++base->current_event_waiters;
2962 			EVTHREAD_COND_WAIT(base->current_event_cond, base->th_base_lock);
2963 		}
2964 #endif
2965 		ev->ev_ncalls = ncalls;
2966 		ev->ev_pncalls = NULL;
2967 	}
2968 
2969 	event_callback_activate_nolock_(base, event_to_event_callback(ev));
2970 }
2971 
2972 void
event_active_later_(struct event * ev,int res)2973 event_active_later_(struct event *ev, int res)
2974 {
2975 	EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock);
2976 	event_active_later_nolock_(ev, res);
2977 	EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock);
2978 }
2979 
2980 void
event_active_later_nolock_(struct event * ev,int res)2981 event_active_later_nolock_(struct event *ev, int res)
2982 {
2983 	struct event_base *base = ev->ev_base;
2984 	EVENT_BASE_ASSERT_LOCKED(base);
2985 
2986 	if (ev->ev_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER)) {
2987 		/* We get different kinds of events, add them together */
2988 		ev->ev_res |= res;
2989 		return;
2990 	}
2991 
2992 	ev->ev_res = res;
2993 
2994 	event_callback_activate_later_nolock_(base, event_to_event_callback(ev));
2995 }
2996 
2997 int
event_callback_activate_(struct event_base * base,struct event_callback * evcb)2998 event_callback_activate_(struct event_base *base,
2999     struct event_callback *evcb)
3000 {
3001 	int r;
3002 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3003 	r = event_callback_activate_nolock_(base, evcb);
3004 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3005 	return r;
3006 }
3007 
3008 int
event_callback_activate_nolock_(struct event_base * base,struct event_callback * evcb)3009 event_callback_activate_nolock_(struct event_base *base,
3010     struct event_callback *evcb)
3011 {
3012 	int r = 1;
3013 
3014 	if (evcb->evcb_flags & EVLIST_FINALIZING)
3015 		return 0;
3016 
3017 	switch (evcb->evcb_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER)) {
3018 	default:
3019 		EVUTIL_ASSERT(0);
3020 		EVUTIL_FALLTHROUGH;
3021 	case EVLIST_ACTIVE_LATER:
3022 		event_queue_remove_active_later(base, evcb);
3023 		r = 0;
3024 		break;
3025 	case EVLIST_ACTIVE:
3026 		return 0;
3027 	case 0:
3028 		break;
3029 	}
3030 
3031 	event_queue_insert_active(base, evcb);
3032 
3033 	if (EVBASE_NEED_NOTIFY(base))
3034 		evthread_notify_base(base);
3035 
3036 	return r;
3037 }
3038 
3039 int
event_callback_activate_later_nolock_(struct event_base * base,struct event_callback * evcb)3040 event_callback_activate_later_nolock_(struct event_base *base,
3041     struct event_callback *evcb)
3042 {
3043 	if (evcb->evcb_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER))
3044 		return 0;
3045 
3046 	event_queue_insert_active_later(base, evcb);
3047 	if (EVBASE_NEED_NOTIFY(base))
3048 		evthread_notify_base(base);
3049 	return 1;
3050 }
3051 
3052 void
event_callback_init_(struct event_base * base,struct event_callback * cb)3053 event_callback_init_(struct event_base *base,
3054     struct event_callback *cb)
3055 {
3056 	memset(cb, 0, sizeof(*cb));
3057 	cb->evcb_pri = base->nactivequeues - 1;
3058 }
3059 
3060 int
event_callback_cancel_(struct event_base * base,struct event_callback * evcb)3061 event_callback_cancel_(struct event_base *base,
3062     struct event_callback *evcb)
3063 {
3064 	int r;
3065 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3066 	r = event_callback_cancel_nolock_(base, evcb, 0);
3067 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3068 	return r;
3069 }
3070 
3071 int
event_callback_cancel_nolock_(struct event_base * base,struct event_callback * evcb,int even_if_finalizing)3072 event_callback_cancel_nolock_(struct event_base *base,
3073     struct event_callback *evcb, int even_if_finalizing)
3074 {
3075 	if ((evcb->evcb_flags & EVLIST_FINALIZING) && !even_if_finalizing)
3076 		return 0;
3077 
3078 	if (evcb->evcb_flags & EVLIST_INIT)
3079 		return event_del_nolock_(event_callback_to_event(evcb),
3080 		    even_if_finalizing ? EVENT_DEL_EVEN_IF_FINALIZING : EVENT_DEL_AUTOBLOCK);
3081 
3082 	switch ((evcb->evcb_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER))) {
3083 	default:
3084 	case EVLIST_ACTIVE|EVLIST_ACTIVE_LATER:
3085 		EVUTIL_ASSERT(0);
3086 		break;
3087 	case EVLIST_ACTIVE:
3088 		/* We get different kinds of events, add them together */
3089 		event_queue_remove_active(base, evcb);
3090 		return 0;
3091 	case EVLIST_ACTIVE_LATER:
3092 		event_queue_remove_active_later(base, evcb);
3093 		break;
3094 	case 0:
3095 		break;
3096 	}
3097 
3098 	return 0;
3099 }
3100 
3101 void
event_deferred_cb_init_(struct event_callback * cb,ev_uint8_t priority,deferred_cb_fn fn,void * arg)3102 event_deferred_cb_init_(struct event_callback *cb, ev_uint8_t priority, deferred_cb_fn fn, void *arg)
3103 {
3104 	memset(cb, 0, sizeof(*cb));
3105 	cb->evcb_cb_union.evcb_selfcb = fn;
3106 	cb->evcb_arg = arg;
3107 	cb->evcb_pri = priority;
3108 	cb->evcb_closure = EV_CLOSURE_CB_SELF;
3109 }
3110 
3111 void
event_deferred_cb_set_priority_(struct event_callback * cb,ev_uint8_t priority)3112 event_deferred_cb_set_priority_(struct event_callback *cb, ev_uint8_t priority)
3113 {
3114 	cb->evcb_pri = priority;
3115 }
3116 
3117 void
event_deferred_cb_cancel_(struct event_base * base,struct event_callback * cb)3118 event_deferred_cb_cancel_(struct event_base *base, struct event_callback *cb)
3119 {
3120 	if (!base)
3121 		base = current_base;
3122 	event_callback_cancel_(base, cb);
3123 }
3124 
3125 #define MAX_DEFERREDS_QUEUED 32
3126 int
event_deferred_cb_schedule_(struct event_base * base,struct event_callback * cb)3127 event_deferred_cb_schedule_(struct event_base *base, struct event_callback *cb)
3128 {
3129 	int r = 1;
3130 	if (!base)
3131 		base = current_base;
3132 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3133 	if (base->n_deferreds_queued > MAX_DEFERREDS_QUEUED) {
3134 		r = event_callback_activate_later_nolock_(base, cb);
3135 	} else {
3136 		r = event_callback_activate_nolock_(base, cb);
3137 		if (r) {
3138 			++base->n_deferreds_queued;
3139 		}
3140 	}
3141 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3142 	return r;
3143 }
3144 
3145 static int
timeout_next(struct event_base * base,struct timeval ** tv_p)3146 timeout_next(struct event_base *base, struct timeval **tv_p)
3147 {
3148 	/* Caller must hold th_base_lock */
3149 	struct timeval now;
3150 	struct event *ev;
3151 	struct timeval *tv = *tv_p;
3152 	int res = 0;
3153 
3154 	ev = min_heap_top_(&base->timeheap);
3155 
3156 	if (ev == NULL) {
3157 		/* if no time-based events are active wait for I/O */
3158 		*tv_p = NULL;
3159 		goto out;
3160 	}
3161 
3162 	if (gettime(base, &now) == -1) {
3163 		res = -1;
3164 		goto out;
3165 	}
3166 
3167 	if (evutil_timercmp(&ev->ev_timeout, &now, <=)) {
3168 		evutil_timerclear(tv);
3169 		goto out;
3170 	}
3171 
3172 	evutil_timersub(&ev->ev_timeout, &now, tv);
3173 
3174 	EVUTIL_ASSERT(tv->tv_sec >= 0);
3175 	EVUTIL_ASSERT(tv->tv_usec >= 0);
3176 	event_debug(("timeout_next: event: %p, in %d seconds, %d useconds", ev, (int)tv->tv_sec, (int)tv->tv_usec));
3177 
3178 out:
3179 	return (res);
3180 }
3181 
3182 /* Activate every event whose timeout has elapsed. */
3183 static void
timeout_process(struct event_base * base)3184 timeout_process(struct event_base *base)
3185 {
3186 	/* Caller must hold lock. */
3187 	struct timeval now;
3188 	struct event *ev;
3189 
3190 	if (min_heap_empty_(&base->timeheap)) {
3191 		return;
3192 	}
3193 
3194 	gettime(base, &now);
3195 
3196 	while ((ev = min_heap_top_(&base->timeheap))) {
3197 		if (evutil_timercmp(&ev->ev_timeout, &now, >))
3198 			break;
3199 
3200 		/* delete this event from the I/O queues */
3201 		event_del_nolock_(ev, EVENT_DEL_NOBLOCK);
3202 
3203 		event_debug(("timeout_process: event: %p, call %p",
3204 			 ev, ev->ev_callback));
3205 		event_active_nolock_(ev, EV_TIMEOUT, 1);
3206 	}
3207 }
3208 
3209 #ifndef MAX
3210 #define MAX(a,b) (((a)>(b))?(a):(b))
3211 #endif
3212 
3213 #define MAX_EVENT_COUNT(var, v) var = MAX(var, v)
3214 
3215 /* These are a fancy way to spell
3216      if (~flags & EVLIST_INTERNAL)
3217          base->event_count--/++;
3218 */
3219 #define DECR_EVENT_COUNT(base,flags) \
3220 	((base)->event_count -= !((flags) & EVLIST_INTERNAL))
3221 #define INCR_EVENT_COUNT(base,flags) do {					\
3222 	((base)->event_count += !((flags) & EVLIST_INTERNAL));			\
3223 	MAX_EVENT_COUNT((base)->event_count_max, (base)->event_count);		\
3224 } while (0)
3225 
3226 static void
event_queue_remove_inserted(struct event_base * base,struct event * ev)3227 event_queue_remove_inserted(struct event_base *base, struct event *ev)
3228 {
3229 	EVENT_BASE_ASSERT_LOCKED(base);
3230 	if (EVUTIL_FAILURE_CHECK(!(ev->ev_flags & EVLIST_INSERTED))) {
3231 		event_errx(1, "%s: %p(fd "EV_SOCK_FMT") not on queue %x", __func__,
3232 		    ev, EV_SOCK_ARG(ev->ev_fd), EVLIST_INSERTED);
3233 		return;
3234 	}
3235 	DECR_EVENT_COUNT(base, ev->ev_flags);
3236 	ev->ev_flags &= ~EVLIST_INSERTED;
3237 }
3238 static void
event_queue_remove_active(struct event_base * base,struct event_callback * evcb)3239 event_queue_remove_active(struct event_base *base, struct event_callback *evcb)
3240 {
3241 	EVENT_BASE_ASSERT_LOCKED(base);
3242 	if (EVUTIL_FAILURE_CHECK(!(evcb->evcb_flags & EVLIST_ACTIVE))) {
3243 		event_errx(1, "%s: %p not on queue %x", __func__,
3244 			   evcb, EVLIST_ACTIVE);
3245 		return;
3246 	}
3247 	DECR_EVENT_COUNT(base, evcb->evcb_flags);
3248 	evcb->evcb_flags &= ~EVLIST_ACTIVE;
3249 	base->event_count_active--;
3250 
3251 	TAILQ_REMOVE(&base->activequeues[evcb->evcb_pri],
3252 	    evcb, evcb_active_next);
3253 }
3254 static void
event_queue_remove_active_later(struct event_base * base,struct event_callback * evcb)3255 event_queue_remove_active_later(struct event_base *base, struct event_callback *evcb)
3256 {
3257 	EVENT_BASE_ASSERT_LOCKED(base);
3258 	if (EVUTIL_FAILURE_CHECK(!(evcb->evcb_flags & EVLIST_ACTIVE_LATER))) {
3259 		event_errx(1, "%s: %p not on queue %x", __func__,
3260 			   evcb, EVLIST_ACTIVE_LATER);
3261 		return;
3262 	}
3263 	DECR_EVENT_COUNT(base, evcb->evcb_flags);
3264 	evcb->evcb_flags &= ~EVLIST_ACTIVE_LATER;
3265 	base->event_count_active--;
3266 
3267 	TAILQ_REMOVE(&base->active_later_queue, evcb, evcb_active_next);
3268 }
3269 static void
event_queue_remove_timeout(struct event_base * base,struct event * ev)3270 event_queue_remove_timeout(struct event_base *base, struct event *ev)
3271 {
3272 	EVENT_BASE_ASSERT_LOCKED(base);
3273 	if (EVUTIL_FAILURE_CHECK(!(ev->ev_flags & EVLIST_TIMEOUT))) {
3274 		event_errx(1, "%s: %p(fd "EV_SOCK_FMT") not on queue %x", __func__,
3275 		    ev, EV_SOCK_ARG(ev->ev_fd), EVLIST_TIMEOUT);
3276 		return;
3277 	}
3278 	DECR_EVENT_COUNT(base, ev->ev_flags);
3279 	ev->ev_flags &= ~EVLIST_TIMEOUT;
3280 
3281 	if (is_common_timeout(&ev->ev_timeout, base)) {
3282 		struct common_timeout_list *ctl =
3283 		    get_common_timeout_list(base, &ev->ev_timeout);
3284 		TAILQ_REMOVE(&ctl->events, ev,
3285 		    ev_timeout_pos.ev_next_with_common_timeout);
3286 	} else {
3287 		min_heap_erase_(&base->timeheap, ev);
3288 	}
3289 }
3290 
3291 #ifdef USE_REINSERT_TIMEOUT
3292 /* Remove and reinsert 'ev' into the timeout queue. */
3293 static void
event_queue_reinsert_timeout(struct event_base * base,struct event * ev,int was_common,int is_common,int old_timeout_idx)3294 event_queue_reinsert_timeout(struct event_base *base, struct event *ev,
3295     int was_common, int is_common, int old_timeout_idx)
3296 {
3297 	struct common_timeout_list *ctl;
3298 	if (!(ev->ev_flags & EVLIST_TIMEOUT)) {
3299 		event_queue_insert_timeout(base, ev);
3300 		return;
3301 	}
3302 
3303 	switch ((was_common<<1) | is_common) {
3304 	case 3: /* Changing from one common timeout to another */
3305 		ctl = base->common_timeout_queues[old_timeout_idx];
3306 		TAILQ_REMOVE(&ctl->events, ev,
3307 		    ev_timeout_pos.ev_next_with_common_timeout);
3308 		ctl = get_common_timeout_list(base, &ev->ev_timeout);
3309 		insert_common_timeout_inorder(ctl, ev);
3310 		break;
3311 	case 2: /* Was common; is no longer common */
3312 		ctl = base->common_timeout_queues[old_timeout_idx];
3313 		TAILQ_REMOVE(&ctl->events, ev,
3314 		    ev_timeout_pos.ev_next_with_common_timeout);
3315 		min_heap_push_(&base->timeheap, ev);
3316 		break;
3317 	case 1: /* Wasn't common; has become common. */
3318 		min_heap_erase_(&base->timeheap, ev);
3319 		ctl = get_common_timeout_list(base, &ev->ev_timeout);
3320 		insert_common_timeout_inorder(ctl, ev);
3321 		break;
3322 	case 0: /* was in heap; is still on heap. */
3323 		min_heap_adjust_(&base->timeheap, ev);
3324 		break;
3325 	default:
3326 		EVUTIL_ASSERT(0); /* unreachable */
3327 		break;
3328 	}
3329 }
3330 #endif
3331 
3332 /* Add 'ev' to the common timeout list in 'ev'. */
3333 static void
insert_common_timeout_inorder(struct common_timeout_list * ctl,struct event * ev)3334 insert_common_timeout_inorder(struct common_timeout_list *ctl,
3335     struct event *ev)
3336 {
3337 	struct event *e;
3338 	/* By all logic, we should just be able to append 'ev' to the end of
3339 	 * ctl->events, since the timeout on each 'ev' is set to {the common
3340 	 * timeout} + {the time when we add the event}, and so the events
3341 	 * should arrive in order of their timeeouts.  But just in case
3342 	 * there's some wacky threading issue going on, we do a search from
3343 	 * the end of 'ev' to find the right insertion point.
3344 	 */
3345 	TAILQ_FOREACH_REVERSE(e, &ctl->events,
3346 	    event_list, ev_timeout_pos.ev_next_with_common_timeout) {
3347 		/* This timercmp is a little sneaky, since both ev and e have
3348 		 * magic values in tv_usec.  Fortunately, they ought to have
3349 		 * the _same_ magic values in tv_usec.  Let's assert for that.
3350 		 */
3351 		EVUTIL_ASSERT(
3352 			is_same_common_timeout(&e->ev_timeout, &ev->ev_timeout));
3353 		if (evutil_timercmp(&ev->ev_timeout, &e->ev_timeout, >=)) {
3354 			TAILQ_INSERT_AFTER(&ctl->events, e, ev,
3355 			    ev_timeout_pos.ev_next_with_common_timeout);
3356 			return;
3357 		}
3358 	}
3359 	TAILQ_INSERT_HEAD(&ctl->events, ev,
3360 	    ev_timeout_pos.ev_next_with_common_timeout);
3361 }
3362 
3363 static void
event_queue_insert_inserted(struct event_base * base,struct event * ev)3364 event_queue_insert_inserted(struct event_base *base, struct event *ev)
3365 {
3366 	EVENT_BASE_ASSERT_LOCKED(base);
3367 
3368 	if (EVUTIL_FAILURE_CHECK(ev->ev_flags & EVLIST_INSERTED)) {
3369 		event_errx(1, "%s: %p(fd "EV_SOCK_FMT") already inserted", __func__,
3370 		    ev, EV_SOCK_ARG(ev->ev_fd));
3371 		return;
3372 	}
3373 
3374 	INCR_EVENT_COUNT(base, ev->ev_flags);
3375 
3376 	ev->ev_flags |= EVLIST_INSERTED;
3377 }
3378 
3379 static void
event_queue_insert_active(struct event_base * base,struct event_callback * evcb)3380 event_queue_insert_active(struct event_base *base, struct event_callback *evcb)
3381 {
3382 	EVENT_BASE_ASSERT_LOCKED(base);
3383 
3384 	if (evcb->evcb_flags & EVLIST_ACTIVE) {
3385 		/* Double insertion is possible for active events */
3386 		return;
3387 	}
3388 
3389 	INCR_EVENT_COUNT(base, evcb->evcb_flags);
3390 
3391 	evcb->evcb_flags |= EVLIST_ACTIVE;
3392 
3393 	base->event_count_active++;
3394 	MAX_EVENT_COUNT(base->event_count_active_max, base->event_count_active);
3395 	EVUTIL_ASSERT(evcb->evcb_pri < base->nactivequeues);
3396 	TAILQ_INSERT_TAIL(&base->activequeues[evcb->evcb_pri],
3397 	    evcb, evcb_active_next);
3398 }
3399 
3400 static void
event_queue_insert_active_later(struct event_base * base,struct event_callback * evcb)3401 event_queue_insert_active_later(struct event_base *base, struct event_callback *evcb)
3402 {
3403 	EVENT_BASE_ASSERT_LOCKED(base);
3404 	if (evcb->evcb_flags & (EVLIST_ACTIVE_LATER|EVLIST_ACTIVE)) {
3405 		/* Double insertion is possible */
3406 		return;
3407 	}
3408 
3409 	INCR_EVENT_COUNT(base, evcb->evcb_flags);
3410 	evcb->evcb_flags |= EVLIST_ACTIVE_LATER;
3411 	base->event_count_active++;
3412 	MAX_EVENT_COUNT(base->event_count_active_max, base->event_count_active);
3413 	EVUTIL_ASSERT(evcb->evcb_pri < base->nactivequeues);
3414 	TAILQ_INSERT_TAIL(&base->active_later_queue, evcb, evcb_active_next);
3415 }
3416 
3417 static void
event_queue_insert_timeout(struct event_base * base,struct event * ev)3418 event_queue_insert_timeout(struct event_base *base, struct event *ev)
3419 {
3420 	EVENT_BASE_ASSERT_LOCKED(base);
3421 
3422 	if (EVUTIL_FAILURE_CHECK(ev->ev_flags & EVLIST_TIMEOUT)) {
3423 		event_errx(1, "%s: %p(fd "EV_SOCK_FMT") already on timeout", __func__,
3424 		    ev, EV_SOCK_ARG(ev->ev_fd));
3425 		return;
3426 	}
3427 
3428 	INCR_EVENT_COUNT(base, ev->ev_flags);
3429 
3430 	ev->ev_flags |= EVLIST_TIMEOUT;
3431 
3432 	if (is_common_timeout(&ev->ev_timeout, base)) {
3433 		struct common_timeout_list *ctl =
3434 		    get_common_timeout_list(base, &ev->ev_timeout);
3435 		insert_common_timeout_inorder(ctl, ev);
3436 	} else {
3437 		min_heap_push_(&base->timeheap, ev);
3438 	}
3439 }
3440 
3441 static void
event_queue_make_later_events_active(struct event_base * base)3442 event_queue_make_later_events_active(struct event_base *base)
3443 {
3444 	struct event_callback *evcb;
3445 	EVENT_BASE_ASSERT_LOCKED(base);
3446 
3447 	while ((evcb = TAILQ_FIRST(&base->active_later_queue))) {
3448 		TAILQ_REMOVE(&base->active_later_queue, evcb, evcb_active_next);
3449 		evcb->evcb_flags = (evcb->evcb_flags & ~EVLIST_ACTIVE_LATER) | EVLIST_ACTIVE;
3450 		EVUTIL_ASSERT(evcb->evcb_pri < base->nactivequeues);
3451 		TAILQ_INSERT_TAIL(&base->activequeues[evcb->evcb_pri], evcb, evcb_active_next);
3452 		base->n_deferreds_queued += (evcb->evcb_closure == EV_CLOSURE_CB_SELF);
3453 	}
3454 }
3455 
3456 /* Functions for debugging */
3457 
3458 const char *
event_get_version(void)3459 event_get_version(void)
3460 {
3461 	return (EVENT__VERSION);
3462 }
3463 
3464 ev_uint32_t
event_get_version_number(void)3465 event_get_version_number(void)
3466 {
3467 	return (EVENT__NUMERIC_VERSION);
3468 }
3469 
3470 /*
3471  * No thread-safe interface needed - the information should be the same
3472  * for all threads.
3473  */
3474 
3475 const char *
event_get_method(void)3476 event_get_method(void)
3477 {
3478 	return (current_base->evsel->name);
3479 }
3480 
3481 #ifndef EVENT__DISABLE_MM_REPLACEMENT
3482 static void *(*mm_malloc_fn_)(size_t sz) = NULL;
3483 static void *(*mm_realloc_fn_)(void *p, size_t sz) = NULL;
3484 static void (*mm_free_fn_)(void *p) = NULL;
3485 
3486 void *
event_mm_malloc_(size_t sz)3487 event_mm_malloc_(size_t sz)
3488 {
3489 	if (sz == 0)
3490 		return NULL;
3491 
3492 	if (mm_malloc_fn_)
3493 		return mm_malloc_fn_(sz);
3494 	else
3495 		return malloc(sz);
3496 }
3497 
3498 void *
event_mm_calloc_(size_t count,size_t size)3499 event_mm_calloc_(size_t count, size_t size)
3500 {
3501 	if (count == 0 || size == 0)
3502 		return NULL;
3503 
3504 	if (mm_malloc_fn_) {
3505 		size_t sz = count * size;
3506 		void *p = NULL;
3507 		if (count > EV_SIZE_MAX / size)
3508 			goto error;
3509 		p = mm_malloc_fn_(sz);
3510 		if (p)
3511 			return memset(p, 0, sz);
3512 	} else {
3513 		void *p = calloc(count, size);
3514 #ifdef _WIN32
3515 		/* Windows calloc doesn't reliably set ENOMEM */
3516 		if (p == NULL)
3517 			goto error;
3518 #endif
3519 		return p;
3520 	}
3521 
3522 error:
3523 	errno = ENOMEM;
3524 	return NULL;
3525 }
3526 
3527 char *
event_mm_strdup_(const char * str)3528 event_mm_strdup_(const char *str)
3529 {
3530 	if (!str) {
3531 		errno = EINVAL;
3532 		return NULL;
3533 	}
3534 
3535 	if (mm_malloc_fn_) {
3536 		size_t ln = strlen(str);
3537 		void *p = NULL;
3538 		if (ln == EV_SIZE_MAX)
3539 			goto error;
3540 		p = mm_malloc_fn_(ln+1);
3541 		if (p)
3542 			return memcpy(p, str, ln+1);
3543 	} else
3544 #ifdef _WIN32
3545 		return _strdup(str);
3546 #else
3547 		return strdup(str);
3548 #endif
3549 
3550 error:
3551 	errno = ENOMEM;
3552 	return NULL;
3553 }
3554 
3555 void *
event_mm_realloc_(void * ptr,size_t sz)3556 event_mm_realloc_(void *ptr, size_t sz)
3557 {
3558 	if (mm_realloc_fn_)
3559 		return mm_realloc_fn_(ptr, sz);
3560 	else
3561 		return realloc(ptr, sz);
3562 }
3563 
3564 void
event_mm_free_(void * ptr)3565 event_mm_free_(void *ptr)
3566 {
3567 	if (mm_free_fn_)
3568 		mm_free_fn_(ptr);
3569 	else
3570 		free(ptr);
3571 }
3572 
3573 void
event_set_mem_functions(void * (* malloc_fn)(size_t sz),void * (* realloc_fn)(void * ptr,size_t sz),void (* free_fn)(void * ptr))3574 event_set_mem_functions(void *(*malloc_fn)(size_t sz),
3575 			void *(*realloc_fn)(void *ptr, size_t sz),
3576 			void (*free_fn)(void *ptr))
3577 {
3578 	mm_malloc_fn_ = malloc_fn;
3579 	mm_realloc_fn_ = realloc_fn;
3580 	mm_free_fn_ = free_fn;
3581 }
3582 #endif
3583 
3584 #ifdef EVENT__HAVE_EVENTFD
3585 static void
evthread_notify_drain_eventfd(evutil_socket_t fd,short what,void * arg)3586 evthread_notify_drain_eventfd(evutil_socket_t fd, short what, void *arg)
3587 {
3588 	ev_uint64_t msg;
3589 	ev_ssize_t r;
3590 	struct event_base *base = arg;
3591 
3592 	r = read(fd, (void*) &msg, sizeof(msg));
3593 	if (r<0 && errno != EAGAIN) {
3594 		event_sock_warn(fd, "Error reading from eventfd");
3595 	}
3596 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3597 	base->is_notify_pending = 0;
3598 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3599 }
3600 #endif
3601 
3602 static void
evthread_notify_drain_default(evutil_socket_t fd,short what,void * arg)3603 evthread_notify_drain_default(evutil_socket_t fd, short what, void *arg)
3604 {
3605 	unsigned char buf[1024];
3606 	struct event_base *base = arg;
3607 #ifdef _WIN32
3608 	while (recv(fd, (char*)buf, sizeof(buf), 0) > 0)
3609 		;
3610 #else
3611 	while (read(fd, (char*)buf, sizeof(buf)) > 0)
3612 		;
3613 #endif
3614 
3615 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3616 	base->is_notify_pending = 0;
3617 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3618 }
3619 
3620 int
evthread_make_base_notifiable(struct event_base * base)3621 evthread_make_base_notifiable(struct event_base *base)
3622 {
3623 	int r;
3624 	if (!base)
3625 		return -1;
3626 
3627 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3628 	r = evthread_make_base_notifiable_nolock_(base);
3629 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3630 	return r;
3631 }
3632 
3633 static int
evthread_make_base_notifiable_nolock_(struct event_base * base)3634 evthread_make_base_notifiable_nolock_(struct event_base *base)
3635 {
3636 	void (*cb)(evutil_socket_t, short, void *);
3637 	int (*notify)(struct event_base *);
3638 
3639 	if (base->th_notify_fn != NULL) {
3640 		/* The base is already notifiable: we're doing fine. */
3641 		return 0;
3642 	}
3643 
3644 #if defined(EVENT__HAVE_WORKING_KQUEUE)
3645 	if (base->evsel == &kqops && event_kq_add_notify_event_(base) == 0) {
3646 		base->th_notify_fn = event_kq_notify_base_;
3647 		/* No need to add an event here; the backend can wake
3648 		 * itself up just fine. */
3649 		return 0;
3650 	}
3651 #endif
3652 
3653 #ifdef EVENT__HAVE_EVENTFD
3654 	base->th_notify_fd[0] = evutil_eventfd_(0,
3655 	    EVUTIL_EFD_CLOEXEC|EVUTIL_EFD_NONBLOCK);
3656 	if (base->th_notify_fd[0] >= 0) {
3657 		base->th_notify_fd[1] = -1;
3658 		notify = evthread_notify_base_eventfd;
3659 		cb = evthread_notify_drain_eventfd;
3660 	} else
3661 #endif
3662 	if (evutil_make_internal_pipe_(base->th_notify_fd) == 0) {
3663 		notify = evthread_notify_base_default;
3664 		cb = evthread_notify_drain_default;
3665 	} else {
3666 		return -1;
3667 	}
3668 
3669 	base->th_notify_fn = notify;
3670 
3671 	/* prepare an event that we can use for wakeup */
3672 	event_assign(&base->th_notify, base, base->th_notify_fd[0],
3673 				 EV_READ|EV_PERSIST, cb, base);
3674 
3675 	/* we need to mark this as internal event */
3676 	base->th_notify.ev_flags |= EVLIST_INTERNAL;
3677 	event_priority_set(&base->th_notify, 0);
3678 
3679 	return event_add_nolock_(&base->th_notify, NULL, 0);
3680 }
3681 
3682 int
event_base_foreach_event_nolock_(struct event_base * base,event_base_foreach_event_cb fn,void * arg)3683 event_base_foreach_event_nolock_(struct event_base *base,
3684     event_base_foreach_event_cb fn, void *arg)
3685 {
3686 	int r, i;
3687 	unsigned u;
3688 	struct event *ev;
3689 
3690 	/* Start out with all the EVLIST_INSERTED events. */
3691 	if ((r = evmap_foreach_event_(base, fn, arg)))
3692 		return r;
3693 
3694 	/* Okay, now we deal with those events that have timeouts and are in
3695 	 * the min-heap. */
3696 	for (u = 0; u < base->timeheap.n; ++u) {
3697 		ev = base->timeheap.p[u];
3698 		if (ev->ev_flags & EVLIST_INSERTED) {
3699 			/* we already processed this one */
3700 			continue;
3701 		}
3702 		if ((r = fn(base, ev, arg)))
3703 			return r;
3704 	}
3705 
3706 	/* Now for the events in one of the timeout queues.
3707 	 * the min-heap. */
3708 	for (i = 0; i < base->n_common_timeouts; ++i) {
3709 		struct common_timeout_list *ctl =
3710 		    base->common_timeout_queues[i];
3711 		TAILQ_FOREACH(ev, &ctl->events,
3712 		    ev_timeout_pos.ev_next_with_common_timeout) {
3713 			if (ev->ev_flags & EVLIST_INSERTED) {
3714 				/* we already processed this one */
3715 				continue;
3716 			}
3717 			if ((r = fn(base, ev, arg)))
3718 				return r;
3719 		}
3720 	}
3721 
3722 	/* Finally, we deal wit all the active events that we haven't touched
3723 	 * yet. */
3724 	for (i = 0; i < base->nactivequeues; ++i) {
3725 		struct event_callback *evcb;
3726 		TAILQ_FOREACH(evcb, &base->activequeues[i], evcb_active_next) {
3727 			if ((evcb->evcb_flags & (EVLIST_INIT|EVLIST_INSERTED|EVLIST_TIMEOUT)) != EVLIST_INIT) {
3728 				/* This isn't an event (evlist_init clear), or
3729 				 * we already processed it. (inserted or
3730 				 * timeout set */
3731 				continue;
3732 			}
3733 			ev = event_callback_to_event(evcb);
3734 			if ((r = fn(base, ev, arg)))
3735 				return r;
3736 		}
3737 	}
3738 
3739 	return 0;
3740 }
3741 
3742 /* Helper for event_base_dump_events: called on each event in the event base;
3743  * dumps only the inserted events. */
3744 static int
dump_inserted_event_fn(const struct event_base * base,const struct event * e,void * arg)3745 dump_inserted_event_fn(const struct event_base *base, const struct event *e, void *arg)
3746 {
3747 	FILE *output = arg;
3748 	const char *gloss = (e->ev_events & EV_SIGNAL) ?
3749 	    "sig" : "fd ";
3750 
3751 	if (! (e->ev_flags & (EVLIST_INSERTED|EVLIST_TIMEOUT)))
3752 		return 0;
3753 
3754 	fprintf(output, "  %p [%s "EV_SOCK_FMT"]%s%s%s%s%s%s%s",
3755 	    (void*)e, gloss, EV_SOCK_ARG(e->ev_fd),
3756 	    (e->ev_events&EV_READ)?" Read":"",
3757 	    (e->ev_events&EV_WRITE)?" Write":"",
3758 	    (e->ev_events&EV_CLOSED)?" EOF":"",
3759 	    (e->ev_events&EV_SIGNAL)?" Signal":"",
3760 	    (e->ev_events&EV_PERSIST)?" Persist":"",
3761 	    (e->ev_events&EV_ET)?" ET":"",
3762 	    (e->ev_flags&EVLIST_INTERNAL)?" Internal":"");
3763 	if (e->ev_flags & EVLIST_TIMEOUT) {
3764 		struct timeval tv;
3765 		tv.tv_sec = e->ev_timeout.tv_sec;
3766 		tv.tv_usec = e->ev_timeout.tv_usec & MICROSECONDS_MASK;
3767 		evutil_timeradd(&tv, &base->tv_clock_diff, &tv);
3768 		fprintf(output, " Timeout=%ld.%06d",
3769 		    (long)tv.tv_sec, (int)(tv.tv_usec & MICROSECONDS_MASK));
3770 	}
3771 	fputc('\n', output);
3772 
3773 	return 0;
3774 }
3775 
3776 /* Helper for event_base_dump_events: called on each event in the event base;
3777  * dumps only the active events. */
3778 static int
dump_active_event_fn(const struct event_base * base,const struct event * e,void * arg)3779 dump_active_event_fn(const struct event_base *base, const struct event *e, void *arg)
3780 {
3781 	FILE *output = arg;
3782 	const char *gloss = (e->ev_events & EV_SIGNAL) ?
3783 	    "sig" : "fd ";
3784 
3785 	if (! (e->ev_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER)))
3786 		return 0;
3787 
3788 	fprintf(output, "  %p [%s "EV_SOCK_FMT", priority=%d]%s%s%s%s%s active%s%s\n",
3789 	    (void*)e, gloss, EV_SOCK_ARG(e->ev_fd), e->ev_pri,
3790 	    (e->ev_res&EV_READ)?" Read":"",
3791 	    (e->ev_res&EV_WRITE)?" Write":"",
3792 	    (e->ev_res&EV_CLOSED)?" EOF":"",
3793 	    (e->ev_res&EV_SIGNAL)?" Signal":"",
3794 	    (e->ev_res&EV_TIMEOUT)?" Timeout":"",
3795 	    (e->ev_flags&EVLIST_INTERNAL)?" [Internal]":"",
3796 	    (e->ev_flags&EVLIST_ACTIVE_LATER)?" [NextTime]":"");
3797 
3798 	return 0;
3799 }
3800 
3801 int
event_base_foreach_event(struct event_base * base,event_base_foreach_event_cb fn,void * arg)3802 event_base_foreach_event(struct event_base *base,
3803     event_base_foreach_event_cb fn, void *arg)
3804 {
3805 	int r;
3806 	if ((!fn) || (!base)) {
3807 		return -1;
3808 	}
3809 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3810 	r = event_base_foreach_event_nolock_(base, fn, arg);
3811 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3812 	return r;
3813 }
3814 
3815 
3816 void
event_base_dump_events(struct event_base * base,FILE * output)3817 event_base_dump_events(struct event_base *base, FILE *output)
3818 {
3819 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3820 	fprintf(output, "Inserted events:\n");
3821 	event_base_foreach_event_nolock_(base, dump_inserted_event_fn, output);
3822 
3823 	fprintf(output, "Active events:\n");
3824 	event_base_foreach_event_nolock_(base, dump_active_event_fn, output);
3825 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3826 }
3827 
3828 void
event_base_active_by_fd(struct event_base * base,evutil_socket_t fd,short events)3829 event_base_active_by_fd(struct event_base *base, evutil_socket_t fd, short events)
3830 {
3831 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3832 
3833 	/* Activate any non timer events */
3834 	if (!(events & EV_TIMEOUT)) {
3835 		evmap_io_active_(base, fd, events & (EV_READ|EV_WRITE|EV_CLOSED));
3836 	} else {
3837 		/* If we want to activate timer events, loop and activate each event with
3838 		 * the same fd in both the timeheap and common timeouts list */
3839 		int i;
3840 		unsigned u;
3841 		struct event *ev;
3842 
3843 		for (u = 0; u < base->timeheap.n; ++u) {
3844 			ev = base->timeheap.p[u];
3845 			if (ev->ev_fd == fd) {
3846 				event_active_nolock_(ev, EV_TIMEOUT, 1);
3847 			}
3848 		}
3849 
3850 		for (i = 0; i < base->n_common_timeouts; ++i) {
3851 			struct common_timeout_list *ctl = base->common_timeout_queues[i];
3852 			TAILQ_FOREACH(ev, &ctl->events,
3853 				ev_timeout_pos.ev_next_with_common_timeout) {
3854 				if (ev->ev_fd == fd) {
3855 					event_active_nolock_(ev, EV_TIMEOUT, 1);
3856 				}
3857 			}
3858 		}
3859 	}
3860 
3861 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3862 }
3863 
3864 void
event_base_active_by_signal(struct event_base * base,int sig)3865 event_base_active_by_signal(struct event_base *base, int sig)
3866 {
3867 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3868 	evmap_signal_active_(base, sig, 1);
3869 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3870 }
3871 
3872 
3873 void
event_base_add_virtual_(struct event_base * base)3874 event_base_add_virtual_(struct event_base *base)
3875 {
3876 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3877 	base->virtual_event_count++;
3878 	MAX_EVENT_COUNT(base->virtual_event_count_max, base->virtual_event_count);
3879 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3880 }
3881 
3882 void
event_base_del_virtual_(struct event_base * base)3883 event_base_del_virtual_(struct event_base *base)
3884 {
3885 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3886 	EVUTIL_ASSERT(base->virtual_event_count > 0);
3887 	base->virtual_event_count--;
3888 	if (base->virtual_event_count == 0 && EVBASE_NEED_NOTIFY(base))
3889 		evthread_notify_base(base);
3890 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3891 }
3892 
3893 static void
event_free_debug_globals_locks(void)3894 event_free_debug_globals_locks(void)
3895 {
3896 #ifndef EVENT__DISABLE_THREAD_SUPPORT
3897 #ifndef EVENT__DISABLE_DEBUG_MODE
3898 	if (event_debug_map_lock_ != NULL) {
3899 		EVTHREAD_FREE_LOCK(event_debug_map_lock_, 0);
3900 		event_debug_map_lock_ = NULL;
3901 		evthreadimpl_disable_lock_debugging_();
3902 	}
3903 #endif /* EVENT__DISABLE_DEBUG_MODE */
3904 #endif /* EVENT__DISABLE_THREAD_SUPPORT */
3905 	return;
3906 }
3907 
3908 static void
event_free_debug_globals(void)3909 event_free_debug_globals(void)
3910 {
3911 	event_free_debug_globals_locks();
3912 }
3913 
3914 static void
event_free_evsig_globals(void)3915 event_free_evsig_globals(void)
3916 {
3917 	evsig_free_globals_();
3918 }
3919 
3920 static void
event_free_evutil_globals(void)3921 event_free_evutil_globals(void)
3922 {
3923 	evutil_free_globals_();
3924 }
3925 
3926 static void
event_free_globals(void)3927 event_free_globals(void)
3928 {
3929 	event_free_debug_globals();
3930 	event_free_evsig_globals();
3931 	event_free_evutil_globals();
3932 }
3933 
3934 void
libevent_global_shutdown(void)3935 libevent_global_shutdown(void)
3936 {
3937 	event_disable_debug_mode();
3938 	event_free_globals();
3939 }
3940 
3941 #ifndef EVENT__DISABLE_THREAD_SUPPORT
3942 int
event_global_setup_locks_(const int enable_locks)3943 event_global_setup_locks_(const int enable_locks)
3944 {
3945 #ifndef EVENT__DISABLE_DEBUG_MODE
3946 	EVTHREAD_SETUP_GLOBAL_LOCK(event_debug_map_lock_, 0);
3947 #endif
3948 	if (evsig_global_setup_locks_(enable_locks) < 0)
3949 		return -1;
3950 	if (evutil_global_setup_locks_(enable_locks) < 0)
3951 		return -1;
3952 	if (evutil_secure_rng_global_setup_locks_(enable_locks) < 0)
3953 		return -1;
3954 	return 0;
3955 }
3956 #endif
3957 
3958 void
event_base_assert_ok_(struct event_base * base)3959 event_base_assert_ok_(struct event_base *base)
3960 {
3961 	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
3962 	event_base_assert_ok_nolock_(base);
3963 	EVBASE_RELEASE_LOCK(base, th_base_lock);
3964 }
3965 
3966 void
event_base_assert_ok_nolock_(struct event_base * base)3967 event_base_assert_ok_nolock_(struct event_base *base)
3968 {
3969 	int i;
3970 	int count;
3971 
3972 	/* First do checks on the per-fd and per-signal lists */
3973 	evmap_check_integrity_(base);
3974 
3975 	/* Check the heap property */
3976 	for (i = 1; i < (int)base->timeheap.n; ++i) {
3977 		int parent = (i - 1) / 2;
3978 		struct event *ev, *p_ev;
3979 		ev = base->timeheap.p[i];
3980 		p_ev = base->timeheap.p[parent];
3981 		EVUTIL_ASSERT(ev->ev_flags & EVLIST_TIMEOUT);
3982 		EVUTIL_ASSERT(evutil_timercmp(&p_ev->ev_timeout, &ev->ev_timeout, <=));
3983 		EVUTIL_ASSERT(ev->ev_timeout_pos.min_heap_idx == i);
3984 	}
3985 
3986 	/* Check that the common timeouts are fine */
3987 	for (i = 0; i < base->n_common_timeouts; ++i) {
3988 		struct common_timeout_list *ctl = base->common_timeout_queues[i];
3989 		struct event *last=NULL, *ev;
3990 
3991 		EVUTIL_ASSERT_TAILQ_OK(&ctl->events, event, ev_timeout_pos.ev_next_with_common_timeout);
3992 
3993 		TAILQ_FOREACH(ev, &ctl->events, ev_timeout_pos.ev_next_with_common_timeout) {
3994 			if (last)
3995 				EVUTIL_ASSERT(evutil_timercmp(&last->ev_timeout, &ev->ev_timeout, <=));
3996 			EVUTIL_ASSERT(ev->ev_flags & EVLIST_TIMEOUT);
3997 			EVUTIL_ASSERT(is_common_timeout(&ev->ev_timeout,base));
3998 			EVUTIL_ASSERT(COMMON_TIMEOUT_IDX(&ev->ev_timeout) == i);
3999 			last = ev;
4000 		}
4001 	}
4002 
4003 	/* Check the active queues. */
4004 	count = 0;
4005 	for (i = 0; i < base->nactivequeues; ++i) {
4006 		struct event_callback *evcb;
4007 		EVUTIL_ASSERT_TAILQ_OK(&base->activequeues[i], event_callback, evcb_active_next);
4008 		TAILQ_FOREACH(evcb, &base->activequeues[i], evcb_active_next) {
4009 			EVUTIL_ASSERT((evcb->evcb_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER)) == EVLIST_ACTIVE);
4010 			EVUTIL_ASSERT(evcb->evcb_pri == i);
4011 			++count;
4012 		}
4013 	}
4014 
4015 	{
4016 		struct event_callback *evcb;
4017 		TAILQ_FOREACH(evcb, &base->active_later_queue, evcb_active_next) {
4018 			EVUTIL_ASSERT((evcb->evcb_flags & (EVLIST_ACTIVE|EVLIST_ACTIVE_LATER)) == EVLIST_ACTIVE_LATER);
4019 			++count;
4020 		}
4021 	}
4022 	EVUTIL_ASSERT(count == base->event_count_active);
4023 }
4024