xref: /freebsd/contrib/unbound/util/ub_event.c (revision 5dae51da3da0cc94d17bd67b308fad304ebec7e0)
1 /*
2  * util/ub_event.c - directly call libevent (compatability) functions
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains and implementation for the indirection layer for pluggable
40  * events that transparently passes it either directly to libevent, or calls
41  * the libevent compatibility layer functions.
42  */
43 #include "config.h"
44 #include <sys/time.h>
45 #include "util/ub_event.h"
46 #include "util/log.h"
47 #include "util/netevent.h"
48 #include "util/tube.h"
49 
50 /* We define libevent structures here to hide the libevent stuff. */
51 
52 #ifdef USE_MINI_EVENT
53 #  ifdef USE_WINSOCK
54 #    include "util/winsock_event.h"
55 #  else
56 #    include "util/mini_event.h"
57 #  endif /* USE_WINSOCK */
58 #else /* USE_MINI_EVENT */
59    /* we use libevent */
60 #  ifdef HAVE_EVENT_H
61 #    include <event.h>
62 #  else
63 #    include "event2/event.h"
64 #    include "event2/event_struct.h"
65 #    include "event2/event_compat.h"
66 #  endif
67 #endif /* USE_MINI_EVENT */
68 
69 #if UB_EV_TIMEOUT != EV_TIMEOUT || UB_EV_READ != EV_READ || \
70     UB_EV_WRITE != EV_WRITE || UB_EV_SIGNAL != EV_SIGNAL || \
71     UB_EV_PERSIST != EV_PERSIST
72 /* Only necessary for libev */
73 #  define NATIVE_BITS(b) ( \
74 	  (((b) & UB_EV_TIMEOUT) ? EV_TIMEOUT : 0) \
75 	| (((b) & UB_EV_READ   ) ? EV_READ    : 0) \
76 	| (((b) & UB_EV_WRITE  ) ? EV_WRITE   : 0) \
77 	| (((b) & UB_EV_SIGNAL ) ? EV_SIGNAL  : 0) \
78 	| (((b) & UB_EV_PERSIST) ? EV_PERSIST : 0))
79 
80 #  define UB_EV_BITS(b) ( \
81 	  (((b) & EV_TIMEOUT) ? UB_EV_TIMEOUT : 0) \
82 	| (((b) & EV_READ   ) ? UB_EV_READ    : 0) \
83 	| (((b) & EV_WRITE  ) ? UB_EV_WRITE   : 0) \
84 	| (((b) & EV_SIGNAL ) ? UB_EV_SIGNAL  : 0) \
85 	| (((b) & EV_PERSIST) ? UB_EV_PERSIST : 0))
86 
87 #  define UB_EV_BITS_CB(C) void my_ ## C (int fd, short bits, void *arg) \
88 	{ (C)(fd, UB_EV_BITS(bits), arg); }
89 
90 UB_EV_BITS_CB(comm_point_udp_callback);
91 UB_EV_BITS_CB(comm_point_udp_ancil_callback)
92 UB_EV_BITS_CB(comm_point_tcp_accept_callback)
93 UB_EV_BITS_CB(comm_point_tcp_handle_callback)
94 UB_EV_BITS_CB(comm_timer_callback)
95 UB_EV_BITS_CB(comm_signal_callback)
96 UB_EV_BITS_CB(comm_point_local_handle_callback)
97 UB_EV_BITS_CB(comm_point_raw_handle_callback)
98 UB_EV_BITS_CB(tube_handle_signal)
99 UB_EV_BITS_CB(comm_base_handle_slow_accept)
100 
101 static void (*NATIVE_BITS_CB(void (*cb)(int, short, void*)))(int, short, void*)
102 {
103 	if(cb == comm_point_udp_callback)
104 		return my_comm_point_udp_callback;
105 	else if(cb == comm_point_udp_ancil_callback)
106 		return my_comm_point_udp_ancil_callback;
107 	else if(cb == comm_point_tcp_accept_callback)
108 		return my_comm_point_tcp_accept_callback;
109 	else if(cb == comm_point_tcp_handle_callback)
110 		return my_comm_point_tcp_handle_callback;
111 	else if(cb == comm_timer_callback)
112 		return my_comm_timer_callback;
113 	else if(cb == comm_signal_callback)
114 		return my_comm_signal_callback;
115 	else if(cb == comm_point_local_handle_callback)
116 		return my_comm_point_local_handle_callback;
117 	else if(cb == comm_point_raw_handle_callback)
118 		return my_comm_point_raw_handle_callback;
119 	else if(cb == tube_handle_signal)
120 		return my_tube_handle_signal;
121 	else if(cb == comm_base_handle_slow_accept)
122 		return my_comm_base_handle_slow_accept;
123 	else
124 		return NULL;
125 }
126 #else
127 #  define NATIVE_BITS(b) (b)
128 #  define NATIVE_BITS_CB(c) (c)
129 #endif
130 
131 #ifndef EVFLAG_AUTO
132 #define EVFLAG_AUTO 0
133 #endif
134 
135 #define AS_EVENT_BASE(x) ((struct event_base*)x)
136 #define AS_UB_EVENT_BASE(x) ((struct ub_event_base*)x)
137 #define AS_EVENT(x) ((struct event*)x)
138 #define AS_UB_EVENT(x) ((struct ub_event*)x)
139 
140 const char* ub_event_get_version(void)
141 {
142 	return event_get_version();
143 }
144 
145 #if (defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)) && defined(EVBACKEND_SELECT)
146 static const char* ub_ev_backend2str(int b)
147 {
148 	switch(b) {
149 	case EVBACKEND_SELECT:	return "select";
150 	case EVBACKEND_POLL:	return "poll";
151 	case EVBACKEND_EPOLL:	return "epoll";
152 	case EVBACKEND_KQUEUE:	return "kqueue";
153 	case EVBACKEND_DEVPOLL: return "devpoll";
154 	case EVBACKEND_PORT:	return "evport";
155 	}
156 	return "unknown";
157 }
158 #endif
159 
160 void
161 ub_get_event_sys(struct ub_event_base* base, const char** n, const char** s,
162 	const char** m)
163 {
164 #ifdef USE_WINSOCK
165 	(void)base;
166 	*n = "event";
167 	*s = "winsock";
168 	*m = "WSAWaitForMultipleEvents";
169 #elif defined(USE_MINI_EVENT)
170 	(void)base;
171 	*n = "mini-event";
172 	*s = "internal";
173 	*m = "select";
174 #else
175 	struct event_base* b = AS_EVENT_BASE(base);
176 	*s = event_get_version();
177 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
178 	*n = "libev";
179 	if (!b)
180 		b = (struct event_base*)ev_default_loop(EVFLAG_AUTO);
181 #    ifdef EVBACKEND_SELECT
182 	*m = ub_ev_backend2str(ev_backend((struct ev_loop*)b));
183 #    else
184 	*m = "not obtainable";
185 #    endif
186 #  elif defined(HAVE_EVENT_BASE_GET_METHOD)
187 	*n = "libevent";
188 	if (!b)
189 		b = event_base_new();
190 	*m = event_base_get_method(b);
191 #  else
192 	*n = "unknown";
193 	*m = "not obtainable";
194 	(void)b;
195 #  endif
196 #  ifdef HAVE_EVENT_BASE_FREE
197 	if (b && b != AS_EVENT_BASE(base))
198 		event_base_free(b);
199 #  endif
200 #endif
201 }
202 
203 struct ub_event_base*
204 ub_default_event_base(int sigs, time_t* time_secs, struct timeval* time_tv)
205 {
206 	void* base;
207 
208 	(void)base;
209 #ifdef USE_MINI_EVENT
210 	(void)sigs;
211 	/* use mini event time-sharing feature */
212 	base = event_init(time_secs, time_tv);
213 #else
214 	(void)time_secs;
215 	(void)time_tv;
216 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
217 	/* libev */
218 	if(sigs)
219 		base = ev_default_loop(EVFLAG_AUTO);
220 	else
221 		base = ev_loop_new(EVFLAG_AUTO);
222 #  else
223 	(void)sigs;
224 #    ifdef HAVE_EVENT_BASE_NEW
225 	base = event_base_new();
226 #    else
227 	base = event_init();
228 #    endif
229 #  endif
230 #endif
231 	return (struct ub_event_base*)base;
232 }
233 
234 struct ub_event_base *
235 ub_libevent_event_base(struct event_base* libevent_base)
236 {
237 #ifdef USE_MINI_EVENT
238 	(void)libevent_base;
239 	return NULL;
240 #else
241 	return AS_UB_EVENT_BASE(libevent_base);
242 #endif
243 }
244 
245 struct event_base *
246 ub_libevent_get_event_base(struct ub_event_base* base)
247 {
248 #ifdef USE_MINI_EVENT
249 	(void)base;
250 	return NULL;
251 #else
252 	return AS_EVENT_BASE(base);
253 #endif
254 }
255 
256 void
257 ub_event_base_free(struct ub_event_base* base)
258 {
259 #ifdef USE_MINI_EVENT
260 	event_base_free(AS_EVENT_BASE(base));
261 #elif defined(HAVE_EVENT_BASE_FREE) && defined(HAVE_EVENT_BASE_ONCE)
262 	/* only libevent 1.2+ has it, but in 1.2 it is broken -
263 	   assertion fails on signal handling ev that is not deleted
264  	   in libevent 1.3c (event_base_once appears) this is fixed. */
265 	event_base_free(AS_EVENT_BASE(base));
266 #else
267 	(void)base;
268 #endif /* HAVE_EVENT_BASE_FREE and HAVE_EVENT_BASE_ONCE */
269 }
270 
271 int
272 ub_event_base_dispatch(struct ub_event_base* base)
273 {
274 	return event_base_dispatch(AS_EVENT_BASE(base));
275 }
276 
277 int
278 ub_event_base_loopexit(struct ub_event_base* base)
279 {
280 	return event_base_loopexit(AS_EVENT_BASE(base), NULL);
281 }
282 
283 struct ub_event*
284 ub_event_new(struct ub_event_base* base, int fd, short bits,
285 	void (*cb)(int, short, void*), void* arg)
286 {
287 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
288 
289 	if (!ev)
290 		return NULL;
291 
292 	event_set(ev, fd, NATIVE_BITS(bits), NATIVE_BITS_CB(cb), arg);
293 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
294 		free(ev);
295 		return NULL;
296 	}
297 	return AS_UB_EVENT(ev);
298 }
299 
300 struct ub_event*
301 ub_signal_new(struct ub_event_base* base, int fd,
302 	void (*cb)(int, short, void*), void* arg)
303 {
304 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
305 
306 	if (!ev)
307 		return NULL;
308 
309 	signal_set(ev, fd, NATIVE_BITS_CB(cb), arg);
310 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
311 		free(ev);
312 		return NULL;
313 	}
314 	return AS_UB_EVENT(ev);
315 }
316 
317 struct ub_event*
318 ub_winsock_register_wsaevent(struct ub_event_base* base, void* wsaevent,
319 	void (*cb)(int, short, void*), void* arg)
320 {
321 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
322 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
323 
324 	if (!ev)
325 		return NULL;
326 
327 	if (winsock_register_wsaevent(AS_EVENT_BASE(base), ev, wsaevent, cb,
328 				arg))
329 		return AS_UB_EVENT(ev);
330 	free(ev);
331 	return NULL;
332 #else
333 	(void)base;
334 	(void)wsaevent;
335 	(void)cb;
336 	(void)arg;
337 	return NULL;
338 #endif
339 }
340 
341 void
342 ub_event_add_bits(struct ub_event* ev, short bits)
343 {
344 	AS_EVENT(ev)->ev_events |= NATIVE_BITS(bits);
345 }
346 
347 void
348 ub_event_del_bits(struct ub_event* ev, short bits)
349 {
350 	AS_EVENT(ev)->ev_events &= ~NATIVE_BITS(bits);
351 }
352 
353 void
354 ub_event_set_fd(struct ub_event* ev, int fd)
355 {
356 	AS_EVENT(ev)->ev_fd = fd;
357 }
358 
359 void
360 ub_event_free(struct ub_event* ev)
361 {
362 	if (ev)
363 		free(AS_EVENT(ev));
364 }
365 
366 int
367 ub_event_add(struct ub_event* ev, struct timeval* tv)
368 {
369 	return event_add(AS_EVENT(ev), tv);
370 }
371 
372 int
373 ub_event_del(struct ub_event* ev)
374 {
375 	return event_del(AS_EVENT(ev));
376 }
377 
378 int
379 ub_timer_add(struct ub_event* ev, struct ub_event_base* base,
380 	void (*cb)(int, short, void*), void* arg, struct timeval* tv)
381 {
382 	event_set(AS_EVENT(ev), -1, EV_TIMEOUT, NATIVE_BITS_CB(cb), arg);
383 	if (event_base_set(AS_EVENT_BASE(base), AS_EVENT(ev)) != 0)
384 		return -1;
385 	return evtimer_add(AS_EVENT(ev), tv);
386 }
387 
388 int
389 ub_timer_del(struct ub_event* ev)
390 {
391 	return evtimer_del(AS_EVENT(ev));
392 }
393 
394 int
395 ub_signal_add(struct ub_event* ev, struct timeval* tv)
396 {
397 	return signal_add(AS_EVENT(ev), tv);
398 }
399 
400 int
401 ub_signal_del(struct ub_event* ev)
402 {
403 	return signal_del(AS_EVENT(ev));
404 }
405 
406 void
407 ub_winsock_unregister_wsaevent(struct ub_event* ev)
408 {
409 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
410 	winsock_unregister_wsaevent(AS_EVENT(ev));
411 	free(AS_EVENT(ev));
412 #else
413 	(void)ev;
414 #endif
415 }
416 
417 void
418 ub_winsock_tcp_wouldblock(struct ub_event* ev, int eventbits)
419 {
420 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
421 	winsock_tcp_wouldblock(AS_EVENT(ev), NATIVE_BITS(eventbits));
422 #else
423 	(void)ev;
424 	(void)eventbits;
425 #endif
426 }
427 
428 void ub_comm_base_now(struct comm_base* cb)
429 {
430 	#ifdef USE_MINI_EVENT
431 /** minievent updates the time when it blocks. */
432 	(void)cb; /* nothing to do */
433 #else /* !USE_MINI_EVENT */
434 /** fillup the time values in the event base */
435 	time_t *tt;
436 	struct timeval *tv;
437 	comm_base_timept(cb, &tt, &tv);
438 	if(gettimeofday(tv, NULL) < 0) {
439 		log_err("gettimeofday: %s", strerror(errno));
440 	}
441 	*tt = tv->tv_sec;
442 #endif /* USE_MINI_EVENT */
443 }
444 
445