xref: /freebsd/contrib/libevent/bufferevent_sock.c (revision 84b3c4547afa496b37e86c5e649e99237c8afc6e)
1 /*
2  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
3  * Copyright (c) 2002-2006 Niels Provos <provos@citi.umich.edu>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include "event2/event-config.h"
30 #include "evconfig-private.h"
31 
32 #include <sys/types.h>
33 
34 #ifdef EVENT__HAVE_SYS_TIME_H
35 #include <sys/time.h>
36 #endif
37 
38 #include <errno.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #ifdef EVENT__HAVE_STDARG_H
43 #include <stdarg.h>
44 #endif
45 #ifdef EVENT__HAVE_UNISTD_H
46 #include <unistd.h>
47 #endif
48 
49 #ifdef _WIN32
50 #include <winsock2.h>
51 #include <ws2tcpip.h>
52 #endif
53 
54 #ifdef EVENT__HAVE_SYS_SOCKET_H
55 #include <sys/socket.h>
56 #endif
57 #ifdef EVENT__HAVE_NETINET_IN_H
58 #include <netinet/in.h>
59 #endif
60 #ifdef EVENT__HAVE_NETINET_IN6_H
61 #include <netinet/in6.h>
62 #endif
63 
64 #include "event2/util.h"
65 #include "event2/bufferevent.h"
66 #include "event2/buffer.h"
67 #include "event2/bufferevent_struct.h"
68 #include "event2/bufferevent_compat.h"
69 #include "event2/event.h"
70 #include "log-internal.h"
71 #include "mm-internal.h"
72 #include "bufferevent-internal.h"
73 #include "util-internal.h"
74 #ifdef _WIN32
75 #include "iocp-internal.h"
76 #endif
77 
78 /* prototypes */
79 static int be_socket_enable(struct bufferevent *, short);
80 static int be_socket_disable(struct bufferevent *, short);
81 static void be_socket_destruct(struct bufferevent *);
82 static int be_socket_flush(struct bufferevent *, short, enum bufferevent_flush_mode);
83 static int be_socket_ctrl(struct bufferevent *, enum bufferevent_ctrl_op, union bufferevent_ctrl_data *);
84 
85 static void be_socket_setfd(struct bufferevent *, evutil_socket_t);
86 
87 const struct bufferevent_ops bufferevent_ops_socket = {
88 	"socket",
89 	evutil_offsetof(struct bufferevent_private, bev),
90 	be_socket_enable,
91 	be_socket_disable,
92 	NULL, /* unlink */
93 	be_socket_destruct,
94 	bufferevent_generic_adj_existing_timeouts_,
95 	be_socket_flush,
96 	be_socket_ctrl,
97 };
98 
99 const struct sockaddr*
100 bufferevent_socket_get_conn_address_(struct bufferevent *bev)
101 {
102 	struct bufferevent_private *bev_p =
103 	    EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
104 
105 	return (struct sockaddr *)&bev_p->conn_address;
106 }
107 static void
108 bufferevent_socket_set_conn_address_fd(struct bufferevent_private *bev_p, int fd)
109 {
110 	socklen_t len = sizeof(bev_p->conn_address);
111 
112 	struct sockaddr *addr = (struct sockaddr *)&bev_p->conn_address;
113 	if (addr->sa_family != AF_UNSPEC)
114 		getpeername(fd, addr, &len);
115 }
116 static void
117 bufferevent_socket_set_conn_address(struct bufferevent_private *bev_p,
118 	struct sockaddr *addr, size_t addrlen)
119 {
120 	EVUTIL_ASSERT(addrlen <= sizeof(bev_p->conn_address));
121 	memcpy(&bev_p->conn_address, addr, addrlen);
122 }
123 
124 static void
125 bufferevent_socket_outbuf_cb(struct evbuffer *buf,
126     const struct evbuffer_cb_info *cbinfo,
127     void *arg)
128 {
129 	struct bufferevent *bufev = arg;
130 	struct bufferevent_private *bufev_p =
131 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
132 
133 	if (cbinfo->n_added &&
134 	    (bufev->enabled & EV_WRITE) &&
135 	    !event_pending(&bufev->ev_write, EV_WRITE, NULL) &&
136 	    !bufev_p->write_suspended) {
137 		/* Somebody added data to the buffer, and we would like to
138 		 * write, and we were not writing.  So, start writing. */
139 		if (bufferevent_add_event_(&bufev->ev_write, &bufev->timeout_write) == -1) {
140 		    /* Should we log this? */
141 		}
142 	}
143 }
144 
145 static void
146 bufferevent_readcb(evutil_socket_t fd, short event, void *arg)
147 {
148 	struct bufferevent *bufev = arg;
149 	struct bufferevent_private *bufev_p =
150 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
151 	struct evbuffer *input;
152 	int res = 0;
153 	short what = BEV_EVENT_READING;
154 	ev_ssize_t howmuch = -1, readmax=-1;
155 
156 	bufferevent_incref_and_lock_(bufev);
157 
158 	if (event == EV_TIMEOUT) {
159 		/* Note that we only check for event==EV_TIMEOUT. If
160 		 * event==EV_TIMEOUT|EV_READ, we can safely ignore the
161 		 * timeout, since a read has occurred */
162 		what |= BEV_EVENT_TIMEOUT;
163 		goto error;
164 	}
165 
166 	input = bufev->input;
167 
168 	/*
169 	 * If we have a high watermark configured then we don't want to
170 	 * read more data than would make us reach the watermark.
171 	 */
172 	if (bufev->wm_read.high != 0) {
173 		howmuch = bufev->wm_read.high - evbuffer_get_length(input);
174 		/* we somehow lowered the watermark, stop reading */
175 		if (howmuch <= 0) {
176 			bufferevent_wm_suspend_read(bufev);
177 			goto done;
178 		}
179 	}
180 	readmax = bufferevent_get_read_max_(bufev_p);
181 	if (howmuch < 0 || howmuch > readmax) /* The use of -1 for "unlimited"
182 					       * uglifies this code. XXXX */
183 		howmuch = readmax;
184 	if (bufev_p->read_suspended)
185 		goto done;
186 
187 	evbuffer_unfreeze(input, 0);
188 	res = evbuffer_read(input, fd, (int)howmuch); /* XXXX evbuffer_read would do better to take and return ev_ssize_t */
189 	evbuffer_freeze(input, 0);
190 
191 	if (res == -1) {
192 		int err = evutil_socket_geterror(fd);
193 		if (EVUTIL_ERR_RW_RETRIABLE(err))
194 			goto reschedule;
195 		if (EVUTIL_ERR_CONNECT_REFUSED(err)) {
196 			bufev_p->connection_refused = 1;
197 			goto done;
198 		}
199 		/* error case */
200 		what |= BEV_EVENT_ERROR;
201 	} else if (res == 0) {
202 		/* eof case */
203 		what |= BEV_EVENT_EOF;
204 	}
205 
206 	if (res <= 0)
207 		goto error;
208 
209 	bufferevent_decrement_read_buckets_(bufev_p, res);
210 
211 	/* Invoke the user callback - must always be called last */
212 	bufferevent_trigger_nolock_(bufev, EV_READ, 0);
213 
214 	goto done;
215 
216  reschedule:
217 	goto done;
218 
219  error:
220 	bufferevent_disable(bufev, EV_READ);
221 	bufferevent_run_eventcb_(bufev, what, 0);
222 
223  done:
224 	bufferevent_decref_and_unlock_(bufev);
225 }
226 
227 static void
228 bufferevent_writecb(evutil_socket_t fd, short event, void *arg)
229 {
230 	struct bufferevent *bufev = arg;
231 	struct bufferevent_private *bufev_p =
232 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
233 	int res = 0;
234 	short what = BEV_EVENT_WRITING;
235 	int connected = 0;
236 	ev_ssize_t atmost = -1;
237 
238 	bufferevent_incref_and_lock_(bufev);
239 
240 	if (event == EV_TIMEOUT) {
241 		/* Note that we only check for event==EV_TIMEOUT. If
242 		 * event==EV_TIMEOUT|EV_WRITE, we can safely ignore the
243 		 * timeout, since a read has occurred */
244 		what |= BEV_EVENT_TIMEOUT;
245 		goto error;
246 	}
247 	if (bufev_p->connecting) {
248 		int c = evutil_socket_finished_connecting_(fd);
249 		/* we need to fake the error if the connection was refused
250 		 * immediately - usually connection to localhost on BSD */
251 		if (bufev_p->connection_refused) {
252 			bufev_p->connection_refused = 0;
253 			c = -1;
254 		}
255 
256 		if (c == 0)
257 			goto done;
258 
259 		bufev_p->connecting = 0;
260 		if (c < 0) {
261 			event_del(&bufev->ev_write);
262 			event_del(&bufev->ev_read);
263 			bufferevent_run_eventcb_(bufev, BEV_EVENT_ERROR, 0);
264 			goto done;
265 		} else {
266 			connected = 1;
267 			bufferevent_socket_set_conn_address_fd(bufev_p, fd);
268 #ifdef _WIN32
269 			if (BEV_IS_ASYNC(bufev)) {
270 				event_del(&bufev->ev_write);
271 				bufferevent_async_set_connected_(bufev);
272 				bufferevent_run_eventcb_(bufev,
273 						BEV_EVENT_CONNECTED, 0);
274 				goto done;
275 			}
276 #endif
277 			bufferevent_run_eventcb_(bufev,
278 					BEV_EVENT_CONNECTED, 0);
279 			if (!(bufev->enabled & EV_WRITE) ||
280 			    bufev_p->write_suspended) {
281 				event_del(&bufev->ev_write);
282 				goto done;
283 			}
284 		}
285 	}
286 
287 	atmost = bufferevent_get_write_max_(bufev_p);
288 
289 	if (bufev_p->write_suspended)
290 		goto done;
291 
292 	if (evbuffer_get_length(bufev->output)) {
293 		evbuffer_unfreeze(bufev->output, 1);
294 		res = evbuffer_write_atmost(bufev->output, fd, atmost);
295 		evbuffer_freeze(bufev->output, 1);
296 		if (res == -1) {
297 			int err = evutil_socket_geterror(fd);
298 			if (EVUTIL_ERR_RW_RETRIABLE(err))
299 				goto reschedule;
300 			what |= BEV_EVENT_ERROR;
301 		} else if (res == 0) {
302 			/* eof case
303 			   XXXX Actually, a 0 on write doesn't indicate
304 			   an EOF. An ECONNRESET might be more typical.
305 			 */
306 			what |= BEV_EVENT_EOF;
307 		}
308 		if (res <= 0)
309 			goto error;
310 
311 		bufferevent_decrement_write_buckets_(bufev_p, res);
312 	}
313 
314 	if (evbuffer_get_length(bufev->output) == 0) {
315 		event_del(&bufev->ev_write);
316 	}
317 
318 	/*
319 	 * Invoke the user callback if our buffer is drained or below the
320 	 * low watermark.
321 	 */
322 	if (res || !connected) {
323 		bufferevent_trigger_nolock_(bufev, EV_WRITE, 0);
324 	}
325 
326 	goto done;
327 
328  reschedule:
329 	if (evbuffer_get_length(bufev->output) == 0) {
330 		event_del(&bufev->ev_write);
331 	}
332 	goto done;
333 
334  error:
335 	bufferevent_disable(bufev, EV_WRITE);
336 	bufferevent_run_eventcb_(bufev, what, 0);
337 
338  done:
339 	bufferevent_decref_and_unlock_(bufev);
340 }
341 
342 struct bufferevent *
343 bufferevent_socket_new(struct event_base *base, evutil_socket_t fd,
344     int options)
345 {
346 	struct bufferevent_private *bufev_p;
347 	struct bufferevent *bufev;
348 
349 #ifdef _WIN32
350 	if (base && event_base_get_iocp_(base))
351 		return bufferevent_async_new_(base, fd, options);
352 #endif
353 
354 	if ((bufev_p = mm_calloc(1, sizeof(struct bufferevent_private)))== NULL)
355 		return NULL;
356 
357 	if (bufferevent_init_common_(bufev_p, base, &bufferevent_ops_socket,
358 				    options) < 0) {
359 		mm_free(bufev_p);
360 		return NULL;
361 	}
362 	bufev = &bufev_p->bev;
363 	evbuffer_set_flags(bufev->output, EVBUFFER_FLAG_DRAINS_TO_FD);
364 
365 	event_assign(&bufev->ev_read, bufev->ev_base, fd,
366 	    EV_READ|EV_PERSIST|EV_FINALIZE, bufferevent_readcb, bufev);
367 	event_assign(&bufev->ev_write, bufev->ev_base, fd,
368 	    EV_WRITE|EV_PERSIST|EV_FINALIZE, bufferevent_writecb, bufev);
369 
370 	evbuffer_add_cb(bufev->output, bufferevent_socket_outbuf_cb, bufev);
371 
372 	evbuffer_freeze(bufev->input, 0);
373 	evbuffer_freeze(bufev->output, 1);
374 
375 	return bufev;
376 }
377 
378 int
379 bufferevent_socket_connect(struct bufferevent *bev,
380     const struct sockaddr *sa, int socklen)
381 {
382 	struct bufferevent_private *bufev_p =
383 	    EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
384 
385 	evutil_socket_t fd;
386 	int r = 0;
387 	int result=-1;
388 	int ownfd = 0;
389 
390 	bufferevent_incref_and_lock_(bev);
391 
392 	if (!bufev_p)
393 		goto done;
394 
395 	fd = bufferevent_getfd(bev);
396 	if (fd < 0) {
397 		if (!sa)
398 			goto done;
399 		fd = evutil_socket_(sa->sa_family,
400 		    SOCK_STREAM|EVUTIL_SOCK_NONBLOCK, 0);
401 		if (fd < 0)
402 			goto done;
403 		ownfd = 1;
404 	}
405 	if (sa) {
406 #ifdef _WIN32
407 		if (bufferevent_async_can_connect_(bev)) {
408 			bufferevent_setfd(bev, fd);
409 			r = bufferevent_async_connect_(bev, fd, sa, socklen);
410 			if (r < 0)
411 				goto freesock;
412 			bufev_p->connecting = 1;
413 			result = 0;
414 			goto done;
415 		} else
416 #endif
417 		r = evutil_socket_connect_(&fd, sa, socklen);
418 		if (r < 0)
419 			goto freesock;
420 	}
421 #ifdef _WIN32
422 	/* ConnectEx() isn't always around, even when IOCP is enabled.
423 	 * Here, we borrow the socket object's write handler to fall back
424 	 * on a non-blocking connect() when ConnectEx() is unavailable. */
425 	if (BEV_IS_ASYNC(bev)) {
426 		event_assign(&bev->ev_write, bev->ev_base, fd,
427 		    EV_WRITE|EV_PERSIST|EV_FINALIZE, bufferevent_writecb, bev);
428 	}
429 #endif
430 	bufferevent_setfd(bev, fd);
431 	if (r == 0) {
432 		if (! be_socket_enable(bev, EV_WRITE)) {
433 			bufev_p->connecting = 1;
434 			result = 0;
435 			goto done;
436 		}
437 	} else if (r == 1) {
438 		/* The connect succeeded already. How very BSD of it. */
439 		result = 0;
440 		bufev_p->connecting = 1;
441 		bufferevent_trigger_nolock_(bev, EV_WRITE, BEV_OPT_DEFER_CALLBACKS);
442 	} else {
443 		/* The connect failed already.  How very BSD of it. */
444 		result = 0;
445 		bufferevent_run_eventcb_(bev, BEV_EVENT_ERROR, BEV_OPT_DEFER_CALLBACKS);
446 		bufferevent_disable(bev, EV_WRITE|EV_READ);
447 	}
448 
449 	goto done;
450 
451 freesock:
452 	bufferevent_run_eventcb_(bev, BEV_EVENT_ERROR, 0);
453 	if (ownfd)
454 		evutil_closesocket(fd);
455 	/* do something about the error? */
456 done:
457 	bufferevent_decref_and_unlock_(bev);
458 	return result;
459 }
460 
461 static void
462 bufferevent_connect_getaddrinfo_cb(int result, struct evutil_addrinfo *ai,
463     void *arg)
464 {
465 	struct bufferevent *bev = arg;
466 	struct bufferevent_private *bev_p =
467 	    EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
468 	int r;
469 	BEV_LOCK(bev);
470 
471 	bufferevent_unsuspend_write_(bev, BEV_SUSPEND_LOOKUP);
472 	bufferevent_unsuspend_read_(bev, BEV_SUSPEND_LOOKUP);
473 
474 	bev_p->dns_request = NULL;
475 
476 	if (result == EVUTIL_EAI_CANCEL) {
477 		bev_p->dns_error = result;
478 		bufferevent_decref_and_unlock_(bev);
479 		return;
480 	}
481 	if (result != 0) {
482 		bev_p->dns_error = result;
483 		bufferevent_run_eventcb_(bev, BEV_EVENT_ERROR, 0);
484 		bufferevent_decref_and_unlock_(bev);
485 		if (ai)
486 			evutil_freeaddrinfo(ai);
487 		return;
488 	}
489 
490 	/* XXX use the other addrinfos? */
491 	/* XXX use this return value */
492 	bufferevent_socket_set_conn_address(bev_p, ai->ai_addr, (int)ai->ai_addrlen);
493 	r = bufferevent_socket_connect(bev, ai->ai_addr, (int)ai->ai_addrlen);
494 	(void)r;
495 	bufferevent_decref_and_unlock_(bev);
496 	evutil_freeaddrinfo(ai);
497 }
498 
499 int
500 bufferevent_socket_connect_hostname(struct bufferevent *bev,
501     struct evdns_base *evdns_base, int family, const char *hostname, int port)
502 {
503 	char portbuf[10];
504 	struct evutil_addrinfo hint;
505 	struct bufferevent_private *bev_p =
506 	    EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
507 
508 	if (family != AF_INET && family != AF_INET6 && family != AF_UNSPEC)
509 		return -1;
510 	if (port < 1 || port > 65535)
511 		return -1;
512 
513 	memset(&hint, 0, sizeof(hint));
514 	hint.ai_family = family;
515 	hint.ai_protocol = IPPROTO_TCP;
516 	hint.ai_socktype = SOCK_STREAM;
517 
518 	evutil_snprintf(portbuf, sizeof(portbuf), "%d", port);
519 
520 	BEV_LOCK(bev);
521 	bev_p->dns_error = 0;
522 
523 	bufferevent_suspend_write_(bev, BEV_SUSPEND_LOOKUP);
524 	bufferevent_suspend_read_(bev, BEV_SUSPEND_LOOKUP);
525 
526 	bufferevent_incref_(bev);
527 	bev_p->dns_request = evutil_getaddrinfo_async_(evdns_base, hostname,
528 	    portbuf, &hint, bufferevent_connect_getaddrinfo_cb, bev);
529 	BEV_UNLOCK(bev);
530 
531 	return 0;
532 }
533 
534 int
535 bufferevent_socket_get_dns_error(struct bufferevent *bev)
536 {
537 	int rv;
538 	struct bufferevent_private *bev_p =
539 	    EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
540 
541 	BEV_LOCK(bev);
542 	rv = bev_p->dns_error;
543 	BEV_UNLOCK(bev);
544 
545 	return rv;
546 }
547 
548 /*
549  * Create a new buffered event object.
550  *
551  * The read callback is invoked whenever we read new data.
552  * The write callback is invoked whenever the output buffer is drained.
553  * The error callback is invoked on a write/read error or on EOF.
554  *
555  * Both read and write callbacks maybe NULL.  The error callback is not
556  * allowed to be NULL and have to be provided always.
557  */
558 
559 struct bufferevent *
560 bufferevent_new(evutil_socket_t fd,
561     bufferevent_data_cb readcb, bufferevent_data_cb writecb,
562     bufferevent_event_cb eventcb, void *cbarg)
563 {
564 	struct bufferevent *bufev;
565 
566 	if (!(bufev = bufferevent_socket_new(NULL, fd, 0)))
567 		return NULL;
568 
569 	bufferevent_setcb(bufev, readcb, writecb, eventcb, cbarg);
570 
571 	return bufev;
572 }
573 
574 
575 static int
576 be_socket_enable(struct bufferevent *bufev, short event)
577 {
578 	if (event & EV_READ &&
579 	    bufferevent_add_event_(&bufev->ev_read, &bufev->timeout_read) == -1)
580 			return -1;
581 	if (event & EV_WRITE &&
582 	    bufferevent_add_event_(&bufev->ev_write, &bufev->timeout_write) == -1)
583 			return -1;
584 	return 0;
585 }
586 
587 static int
588 be_socket_disable(struct bufferevent *bufev, short event)
589 {
590 	struct bufferevent_private *bufev_p =
591 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
592 	if (event & EV_READ) {
593 		if (event_del(&bufev->ev_read) == -1)
594 			return -1;
595 	}
596 	/* Don't actually disable the write if we are trying to connect. */
597 	if ((event & EV_WRITE) && ! bufev_p->connecting) {
598 		if (event_del(&bufev->ev_write) == -1)
599 			return -1;
600 	}
601 	return 0;
602 }
603 
604 static void
605 be_socket_destruct(struct bufferevent *bufev)
606 {
607 	struct bufferevent_private *bufev_p =
608 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
609 	evutil_socket_t fd;
610 	EVUTIL_ASSERT(bufev->be_ops == &bufferevent_ops_socket);
611 
612 	fd = event_get_fd(&bufev->ev_read);
613 
614 	if ((bufev_p->options & BEV_OPT_CLOSE_ON_FREE) && fd >= 0)
615 		EVUTIL_CLOSESOCKET(fd);
616 
617 	evutil_getaddrinfo_cancel_async_(bufev_p->dns_request);
618 }
619 
620 static int
621 be_socket_flush(struct bufferevent *bev, short iotype,
622     enum bufferevent_flush_mode mode)
623 {
624 	return 0;
625 }
626 
627 
628 static void
629 be_socket_setfd(struct bufferevent *bufev, evutil_socket_t fd)
630 {
631 	struct bufferevent_private *bufev_p =
632 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
633 
634 	BEV_LOCK(bufev);
635 	EVUTIL_ASSERT(bufev->be_ops == &bufferevent_ops_socket);
636 
637 	event_del(&bufev->ev_read);
638 	event_del(&bufev->ev_write);
639 
640 	evbuffer_unfreeze(bufev->input, 0);
641 	evbuffer_unfreeze(bufev->output, 1);
642 
643 	event_assign(&bufev->ev_read, bufev->ev_base, fd,
644 	    EV_READ|EV_PERSIST|EV_FINALIZE, bufferevent_readcb, bufev);
645 	event_assign(&bufev->ev_write, bufev->ev_base, fd,
646 	    EV_WRITE|EV_PERSIST|EV_FINALIZE, bufferevent_writecb, bufev);
647 
648 	if (fd >= 0)
649 		bufferevent_enable(bufev, bufev->enabled);
650 
651 	evutil_getaddrinfo_cancel_async_(bufev_p->dns_request);
652 
653 	BEV_UNLOCK(bufev);
654 }
655 
656 /* XXXX Should non-socket bufferevents support this? */
657 int
658 bufferevent_priority_set(struct bufferevent *bufev, int priority)
659 {
660 	int r = -1;
661 	struct bufferevent_private *bufev_p =
662 	    EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
663 
664 	BEV_LOCK(bufev);
665 	if (bufev->be_ops != &bufferevent_ops_socket)
666 		goto done;
667 
668 	if (event_priority_set(&bufev->ev_read, priority) == -1)
669 		goto done;
670 	if (event_priority_set(&bufev->ev_write, priority) == -1)
671 		goto done;
672 
673 	event_deferred_cb_set_priority_(&bufev_p->deferred, priority);
674 
675 	r = 0;
676 done:
677 	BEV_UNLOCK(bufev);
678 	return r;
679 }
680 
681 /* XXXX Should non-socket bufferevents support this? */
682 int
683 bufferevent_base_set(struct event_base *base, struct bufferevent *bufev)
684 {
685 	int res = -1;
686 
687 	BEV_LOCK(bufev);
688 	if (bufev->be_ops != &bufferevent_ops_socket)
689 		goto done;
690 
691 	bufev->ev_base = base;
692 
693 	res = event_base_set(base, &bufev->ev_read);
694 	if (res == -1)
695 		goto done;
696 
697 	res = event_base_set(base, &bufev->ev_write);
698 done:
699 	BEV_UNLOCK(bufev);
700 	return res;
701 }
702 
703 static int
704 be_socket_ctrl(struct bufferevent *bev, enum bufferevent_ctrl_op op,
705     union bufferevent_ctrl_data *data)
706 {
707 	switch (op) {
708 	case BEV_CTRL_SET_FD:
709 		be_socket_setfd(bev, data->fd);
710 		return 0;
711 	case BEV_CTRL_GET_FD:
712 		data->fd = event_get_fd(&bev->ev_read);
713 		return 0;
714 	case BEV_CTRL_GET_UNDERLYING:
715 	case BEV_CTRL_CANCEL_ALL:
716 	default:
717 		return -1;
718 	}
719 }
720