xref: /freebsd/contrib/unbound/util/ub_event.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
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) \
136 	(((union {struct ub_event_base* a; struct event_base* b;})x).b)
137 #define AS_UB_EVENT_BASE(x) \
138 	(((union {struct event_base* a; struct ub_event_base* b;})x).b)
139 #define AS_EVENT(x) \
140 	(((union {struct ub_event* a; struct event* b;})x).b)
141 #define AS_UB_EVENT(x) \
142 	(((union {struct event* a; struct ub_event* b;})x).b)
143 
144 const char* ub_event_get_version()
145 {
146 	return event_get_version();
147 }
148 
149 #if (defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)) && defined(EVBACKEND_SELECT)
150 static const char* ub_ev_backend2str(int b)
151 {
152 	switch(b) {
153 	case EVBACKEND_SELECT:	return "select";
154 	case EVBACKEND_POLL:	return "poll";
155 	case EVBACKEND_EPOLL:	return "epoll";
156 	case EVBACKEND_KQUEUE:	return "kqueue";
157 	case EVBACKEND_DEVPOLL: return "devpoll";
158 	case EVBACKEND_PORT:	return "evport";
159 	}
160 	return "unknown";
161 }
162 #endif
163 
164 void
165 ub_get_event_sys(struct ub_event_base* base, const char** n, const char** s,
166 	const char** m)
167 {
168 #ifdef USE_WINSOCK
169 	(void)base;
170 	*n = "event";
171 	*s = "winsock";
172 	*m = "WSAWaitForMultipleEvents";
173 #elif defined(USE_MINI_EVENT)
174 	(void)base;
175 	*n = "mini-event";
176 	*s = "internal";
177 	*m = "select";
178 #else
179 	struct event_base* b = AS_EVENT_BASE(base);
180 	*s = event_get_version();
181 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
182 	*n = "libev";
183 	if (!b)
184 		b = (struct event_base*)ev_default_loop(EVFLAG_AUTO);
185 #    ifdef EVBACKEND_SELECT
186 	*m = ub_ev_backend2str(ev_backend((struct ev_loop*)b));
187 #    else
188 	*m = "not obtainable";
189 #    endif
190 #  elif defined(HAVE_EVENT_BASE_GET_METHOD)
191 	*n = "libevent";
192 	if (!b)
193 		b = event_base_new();
194 	*m = event_base_get_method(b);
195 #  else
196 	*n = "unknown";
197 	*m = "not obtainable";
198 	(void)b;
199 #  endif
200 #  ifdef HAVE_EVENT_BASE_FREE
201 	if (b && b != AS_EVENT_BASE(base))
202 		event_base_free(b);
203 #  endif
204 #endif
205 }
206 
207 struct ub_event_base*
208 ub_default_event_base(int sigs, time_t* time_secs, struct timeval* time_tv)
209 {
210 	void* base;
211 
212 	(void)base;
213 #ifdef USE_MINI_EVENT
214 	(void)sigs;
215 	/* use mini event time-sharing feature */
216 	base = event_init(time_secs, time_tv);
217 #else
218 	(void)time_secs;
219 	(void)time_tv;
220 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
221 	/* libev */
222 	if(sigs)
223 		base = ev_default_loop(EVFLAG_AUTO);
224 	else
225 		base = ev_loop_new(EVFLAG_AUTO);
226 #  else
227 	(void)sigs;
228 #    ifdef HAVE_EVENT_BASE_NEW
229 	base = event_base_new();
230 #    else
231 	base = event_init();
232 #    endif
233 #  endif
234 #endif
235 	return (struct ub_event_base*)base;
236 }
237 
238 struct ub_event_base *
239 ub_libevent_event_base(struct event_base* libevent_base)
240 {
241 #ifdef USE_MINI_EVENT
242 	(void)libevent_base;
243 	return NULL;
244 #else
245 	return AS_UB_EVENT_BASE(libevent_base);
246 #endif
247 }
248 
249 struct event_base *
250 ub_libevent_get_event_base(struct ub_event_base* base)
251 {
252 #ifdef USE_MINI_EVENT
253 	(void)base;
254 	return NULL;
255 #else
256 	return AS_EVENT_BASE(base);
257 #endif
258 }
259 
260 void
261 ub_event_base_free(struct ub_event_base* base)
262 {
263 #ifdef USE_MINI_EVENT
264 	event_base_free(AS_EVENT_BASE(base));
265 #elif defined(HAVE_EVENT_BASE_FREE) && defined(HAVE_EVENT_BASE_ONCE)
266 	/* only libevent 1.2+ has it, but in 1.2 it is broken -
267 	   assertion fails on signal handling ev that is not deleted
268  	   in libevent 1.3c (event_base_once appears) this is fixed. */
269 	event_base_free(AS_EVENT_BASE(base));
270 #else
271 	(void)base;
272 #endif /* HAVE_EVENT_BASE_FREE and HAVE_EVENT_BASE_ONCE */
273 }
274 
275 int
276 ub_event_base_dispatch(struct ub_event_base* base)
277 {
278 	return event_base_dispatch(AS_EVENT_BASE(base));
279 }
280 
281 int
282 ub_event_base_loopexit(struct ub_event_base* base)
283 {
284 	return event_base_loopexit(AS_EVENT_BASE(base), NULL);
285 }
286 
287 struct ub_event*
288 ub_event_new(struct ub_event_base* base, int fd, short bits,
289 	void (*cb)(int, short, void*), void* arg)
290 {
291 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
292 
293 	if (!ev)
294 		return NULL;
295 
296 	event_set(ev, fd, NATIVE_BITS(bits), NATIVE_BITS_CB(cb), arg);
297 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
298 		free(ev);
299 		return NULL;
300 	}
301 	return AS_UB_EVENT(ev);
302 }
303 
304 struct ub_event*
305 ub_signal_new(struct ub_event_base* base, int fd,
306 	void (*cb)(int, short, void*), void* arg)
307 {
308 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
309 
310 	if (!ev)
311 		return NULL;
312 
313 	signal_set(ev, fd, NATIVE_BITS_CB(cb), arg);
314 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
315 		free(ev);
316 		return NULL;
317 	}
318 	return AS_UB_EVENT(ev);
319 }
320 
321 struct ub_event*
322 ub_winsock_register_wsaevent(struct ub_event_base* base, void* wsaevent,
323 	void (*cb)(int, short, void*), void* arg)
324 {
325 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
326 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
327 
328 	if (!ev)
329 		return NULL;
330 
331 	if (winsock_register_wsaevent(AS_EVENT_BASE(base), ev, wsaevent, cb,
332 				arg))
333 		return AS_UB_EVENT(ev);
334 	free(ev);
335 	return NULL;
336 #else
337 	(void)base;
338 	(void)wsaevent;
339 	(void)cb;
340 	(void)arg;
341 	return NULL;
342 #endif
343 }
344 
345 void
346 ub_event_add_bits(struct ub_event* ev, short bits)
347 {
348 	AS_EVENT(ev)->ev_events |= NATIVE_BITS(bits);
349 }
350 
351 void
352 ub_event_del_bits(struct ub_event* ev, short bits)
353 {
354 	AS_EVENT(ev)->ev_events &= ~NATIVE_BITS(bits);
355 }
356 
357 void
358 ub_event_set_fd(struct ub_event* ev, int fd)
359 {
360 	AS_EVENT(ev)->ev_fd = fd;
361 }
362 
363 void
364 ub_event_free(struct ub_event* ev)
365 {
366 	if (ev)
367 		free(AS_EVENT(ev));
368 }
369 
370 int
371 ub_event_add(struct ub_event* ev, struct timeval* tv)
372 {
373 	return event_add(AS_EVENT(ev), tv);
374 }
375 
376 int
377 ub_event_del(struct ub_event* ev)
378 {
379 	return event_del(AS_EVENT(ev));
380 }
381 
382 int
383 ub_timer_add(struct ub_event* ev, struct ub_event_base* base,
384 	void (*cb)(int, short, void*), void* arg, struct timeval* tv)
385 {
386 	event_set(AS_EVENT(ev), -1, EV_TIMEOUT, NATIVE_BITS_CB(cb), arg);
387 	if (event_base_set(AS_EVENT_BASE(base), AS_EVENT(ev)) != 0)
388 		return -1;
389 	return evtimer_add(AS_EVENT(ev), tv);
390 }
391 
392 int
393 ub_timer_del(struct ub_event* ev)
394 {
395 	return evtimer_del(AS_EVENT(ev));
396 }
397 
398 int
399 ub_signal_add(struct ub_event* ev, struct timeval* tv)
400 {
401 	return signal_add(AS_EVENT(ev), tv);
402 }
403 
404 int
405 ub_signal_del(struct ub_event* ev)
406 {
407 	return signal_del(AS_EVENT(ev));
408 }
409 
410 void
411 ub_winsock_unregister_wsaevent(struct ub_event* ev)
412 {
413 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
414 	winsock_unregister_wsaevent(AS_EVENT(ev));
415 	free(AS_EVENT(ev));
416 #else
417 	(void)ev;
418 #endif
419 }
420 
421 void
422 ub_winsock_tcp_wouldblock(struct ub_event* ev, int eventbits)
423 {
424 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
425 	winsock_tcp_wouldblock(AS_EVENT(ev), NATIVE_BITS(eventbits));
426 #else
427 	(void)ev;
428 	(void)eventbits;
429 #endif
430 }
431 
432 void ub_comm_base_now(struct comm_base* cb)
433 {
434 	#ifdef USE_MINI_EVENT
435 /** minievent updates the time when it blocks. */
436 	(void)cb; /* nothing to do */
437 #else /* !USE_MINI_EVENT */
438 /** fillup the time values in the event base */
439 	time_t *tt;
440 	struct timeval *tv;
441 	comm_base_timept(cb, &tt, &tv);
442 	if(gettimeofday(tv, NULL) < 0) {
443 		log_err("gettimeofday: %s", strerror(errno));
444 	}
445 	*tt = tv->tv_sec;
446 #endif /* USE_MINI_EVENT */
447 }
448 
449