xref: /freebsd/contrib/unbound/util/ub_event.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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(comm_point_http_handle_callback)
99 UB_EV_BITS_CB(tube_handle_signal)
100 UB_EV_BITS_CB(comm_base_handle_slow_accept)
101 
102 static void (*NATIVE_BITS_CB(void (*cb)(int, short, void*)))(int, short, void*)
103 {
104 	if(cb == comm_point_udp_callback)
105 		return my_comm_point_udp_callback;
106 	else if(cb == comm_point_udp_ancil_callback)
107 		return my_comm_point_udp_ancil_callback;
108 	else if(cb == comm_point_tcp_accept_callback)
109 		return my_comm_point_tcp_accept_callback;
110 	else if(cb == comm_point_tcp_handle_callback)
111 		return my_comm_point_tcp_handle_callback;
112 	else if(cb == comm_timer_callback)
113 		return my_comm_timer_callback;
114 	else if(cb == comm_signal_callback)
115 		return my_comm_signal_callback;
116 	else if(cb == comm_point_local_handle_callback)
117 		return my_comm_point_local_handle_callback;
118 	else if(cb == comm_point_raw_handle_callback)
119 		return my_comm_point_raw_handle_callback;
120 	else if(cb == comm_point_http_handle_callback)
121 		return my_comm_point_http_handle_callback;
122 	else if(cb == tube_handle_signal)
123 		return my_tube_handle_signal;
124 	else if(cb == comm_base_handle_slow_accept)
125 		return my_comm_base_handle_slow_accept;
126 	else {
127 		log_assert(0); /* this NULL callback pointer should not happen,
128 			we should have the necessary routine listed above */
129 		return NULL;
130 	}
131 }
132 #else
133 #  define NATIVE_BITS(b) (b)
134 #  define NATIVE_BITS_CB(c) (c)
135 #endif
136 
137 #ifndef EVFLAG_AUTO
138 #define EVFLAG_AUTO 0
139 #endif
140 
141 #define AS_EVENT_BASE(x) ((struct event_base*)x)
142 #define AS_UB_EVENT_BASE(x) ((struct ub_event_base*)x)
143 #define AS_EVENT(x) ((struct event*)x)
144 #define AS_UB_EVENT(x) ((struct ub_event*)x)
145 
146 const char* ub_event_get_version(void)
147 {
148 	return event_get_version();
149 }
150 
151 #if (defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)) && defined(EV_FEATURE_BACKENDS)
152 static const char* ub_ev_backend2str(int b)
153 {
154 	switch(b) {
155 	case EVBACKEND_SELECT:	return "select";
156 	case EVBACKEND_POLL:	return "poll";
157 	case EVBACKEND_EPOLL:	return "epoll";
158 	case EVBACKEND_KQUEUE:	return "kqueue";
159 	case EVBACKEND_DEVPOLL: return "devpoll";
160 	case EVBACKEND_PORT:	return "evport";
161 	}
162 	return "unknown";
163 }
164 #endif
165 
166 void
167 ub_get_event_sys(struct ub_event_base* base, const char** n, const char** s,
168 	const char** m)
169 {
170 #ifdef USE_WINSOCK
171 	(void)base;
172 	*n = "event";
173 	*s = "winsock";
174 	*m = "WSAWaitForMultipleEvents";
175 #elif defined(USE_MINI_EVENT)
176 	(void)base;
177 	*n = "mini-event";
178 	*s = "internal";
179 	*m = "select";
180 #else
181 	struct event_base* b = AS_EVENT_BASE(base);
182 	*s = event_get_version();
183 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
184 	*n = "libev";
185 	if (!b)
186 		b = (struct event_base*)ev_default_loop(EVFLAG_AUTO);
187 #    ifdef EV_FEATURE_BACKENDS
188 	*m = ub_ev_backend2str(ev_backend((struct ev_loop*)b));
189 #    else
190 	*m = "not obtainable";
191 #    endif
192 #  elif defined(HAVE_EVENT_BASE_GET_METHOD)
193 	*n = "libevent";
194 	if (!b)
195 		b = event_base_new();
196 	*m = event_base_get_method(b);
197 #  else
198 	*n = "unknown";
199 	*m = "not obtainable";
200 	(void)b;
201 #  endif
202 #  ifdef HAVE_EVENT_BASE_FREE
203 	if (b && b != AS_EVENT_BASE(base))
204 		event_base_free(b);
205 #  endif
206 #endif
207 }
208 
209 struct ub_event_base*
210 ub_default_event_base(int sigs, time_t* time_secs, struct timeval* time_tv)
211 {
212 	void* base;
213 
214 	(void)base;
215 #ifdef USE_MINI_EVENT
216 	(void)sigs;
217 	/* use mini event time-sharing feature */
218 	base = event_init(time_secs, time_tv);
219 #else
220 	(void)time_secs;
221 	(void)time_tv;
222 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
223 	/* libev */
224 	if(sigs)
225 		base = ev_default_loop(EVFLAG_AUTO);
226 	else
227 		base = ev_loop_new(EVFLAG_AUTO);
228 #  else
229 	(void)sigs;
230 #    ifdef HAVE_EVENT_BASE_NEW
231 	base = event_base_new();
232 #    else
233 	base = event_init();
234 #    endif
235 #  endif
236 #endif
237 	return (struct ub_event_base*)base;
238 }
239 
240 struct ub_event_base *
241 ub_libevent_event_base(struct event_base* libevent_base)
242 {
243 #ifdef USE_MINI_EVENT
244 	(void)libevent_base;
245 	return NULL;
246 #else
247 	return AS_UB_EVENT_BASE(libevent_base);
248 #endif
249 }
250 
251 struct event_base *
252 ub_libevent_get_event_base(struct ub_event_base* base)
253 {
254 #ifdef USE_MINI_EVENT
255 	(void)base;
256 	return NULL;
257 #else
258 	return AS_EVENT_BASE(base);
259 #endif
260 }
261 
262 void
263 ub_event_base_free(struct ub_event_base* base)
264 {
265 #ifdef USE_MINI_EVENT
266 	event_base_free(AS_EVENT_BASE(base));
267 #elif defined(HAVE_EVENT_BASE_FREE) && defined(HAVE_EVENT_BASE_ONCE)
268 	/* only libevent 1.2+ has it, but in 1.2 it is broken -
269 	   assertion fails on signal handling ev that is not deleted
270  	   in libevent 1.3c (event_base_once appears) this is fixed. */
271 	event_base_free(AS_EVENT_BASE(base));
272 #else
273 	(void)base;
274 #endif /* HAVE_EVENT_BASE_FREE and HAVE_EVENT_BASE_ONCE */
275 }
276 
277 int
278 ub_event_base_dispatch(struct ub_event_base* base)
279 {
280 	return event_base_dispatch(AS_EVENT_BASE(base));
281 }
282 
283 int
284 ub_event_base_loopexit(struct ub_event_base* base)
285 {
286 	return event_base_loopexit(AS_EVENT_BASE(base), NULL);
287 }
288 
289 struct ub_event*
290 ub_event_new(struct ub_event_base* base, int fd, short bits,
291 	void (*cb)(int, short, void*), void* arg)
292 {
293 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
294 
295 	if (!ev)
296 		return NULL;
297 
298 #ifndef HAVE_EVENT_ASSIGN
299 	event_set(ev, fd, NATIVE_BITS(bits), NATIVE_BITS_CB(cb), arg);
300 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
301 		free(ev);
302 		return NULL;
303 	}
304 #else
305 	if (event_assign(ev, AS_EVENT_BASE(base), fd, bits, cb, arg) != 0) {
306 		free(ev);
307 		return NULL;
308 	}
309 #endif
310 	return AS_UB_EVENT(ev);
311 }
312 
313 struct ub_event*
314 ub_signal_new(struct ub_event_base* base, int fd,
315 	void (*cb)(int, short, void*), void* arg)
316 {
317 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
318 
319 	if (!ev)
320 		return NULL;
321 
322 #if !HAVE_DECL_EVSIGNAL_ASSIGN
323 	signal_set(ev, fd, NATIVE_BITS_CB(cb), arg);
324 	if (event_base_set(AS_EVENT_BASE(base), ev) != 0) {
325 		free(ev);
326 		return NULL;
327 	}
328 #else
329 	if (evsignal_assign(ev, AS_EVENT_BASE(base), fd, cb, arg) != 0) {
330 		free(ev);
331 		return NULL;
332 	}
333 #endif
334 	return AS_UB_EVENT(ev);
335 }
336 
337 struct ub_event*
338 ub_winsock_register_wsaevent(struct ub_event_base* base, void* wsaevent,
339 	void (*cb)(int, short, void*), void* arg)
340 {
341 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
342 	struct event *ev = (struct event*)calloc(1, sizeof(struct event));
343 
344 	if (!ev)
345 		return NULL;
346 
347 	if (winsock_register_wsaevent(AS_EVENT_BASE(base), ev, wsaevent, cb,
348 				arg))
349 		return AS_UB_EVENT(ev);
350 	free(ev);
351 	return NULL;
352 #else
353 	(void)base;
354 	(void)wsaevent;
355 	(void)cb;
356 	(void)arg;
357 	return NULL;
358 #endif
359 }
360 
361 void
362 ub_event_add_bits(struct ub_event* ev, short bits)
363 {
364 	AS_EVENT(ev)->ev_events |= NATIVE_BITS(bits);
365 }
366 
367 void
368 ub_event_del_bits(struct ub_event* ev, short bits)
369 {
370 	AS_EVENT(ev)->ev_events &= ~NATIVE_BITS(bits);
371 }
372 
373 void
374 ub_event_set_fd(struct ub_event* ev, int fd)
375 {
376 	AS_EVENT(ev)->ev_fd = fd;
377 }
378 
379 void
380 ub_event_free(struct ub_event* ev)
381 {
382 	if (ev)
383 		free(AS_EVENT(ev));
384 }
385 
386 int
387 ub_event_add(struct ub_event* ev, struct timeval* tv)
388 {
389 	return event_add(AS_EVENT(ev), tv);
390 }
391 
392 int
393 ub_event_del(struct ub_event* ev)
394 {
395 	return event_del(AS_EVENT(ev));
396 }
397 
398 int
399 ub_timer_add(struct ub_event* ev, struct ub_event_base* base,
400 	void (*cb)(int, short, void*), void* arg, struct timeval* tv)
401 {
402 	event_set(AS_EVENT(ev), -1, EV_TIMEOUT, NATIVE_BITS_CB(cb), arg);
403 	if (event_base_set(AS_EVENT_BASE(base), AS_EVENT(ev)) != 0)
404 		return -1;
405 	return evtimer_add(AS_EVENT(ev), tv);
406 }
407 
408 int
409 ub_timer_del(struct ub_event* ev)
410 {
411 	return evtimer_del(AS_EVENT(ev));
412 }
413 
414 int
415 ub_signal_add(struct ub_event* ev, struct timeval* tv)
416 {
417 	return signal_add(AS_EVENT(ev), tv);
418 }
419 
420 int
421 ub_signal_del(struct ub_event* ev)
422 {
423 	return signal_del(AS_EVENT(ev));
424 }
425 
426 void
427 ub_winsock_unregister_wsaevent(struct ub_event* ev)
428 {
429 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
430 	winsock_unregister_wsaevent(AS_EVENT(ev));
431 	free(AS_EVENT(ev));
432 #else
433 	(void)ev;
434 #endif
435 }
436 
437 void
438 ub_winsock_tcp_wouldblock(struct ub_event* ev, int eventbits)
439 {
440 #if defined(USE_MINI_EVENT) && defined(USE_WINSOCK)
441 	winsock_tcp_wouldblock(AS_EVENT(ev), NATIVE_BITS(eventbits));
442 #else
443 	(void)ev;
444 	(void)eventbits;
445 #endif
446 }
447 
448 void ub_comm_base_now(struct comm_base* cb)
449 {
450 #ifdef USE_MINI_EVENT
451 /** minievent updates the time when it blocks. */
452 	(void)cb; /* nothing to do */
453 #else /* !USE_MINI_EVENT */
454 /** fillup the time values in the event base */
455 	time_t *tt;
456 	struct timeval *tv;
457 	comm_base_timept(cb, &tt, &tv);
458 	if(gettimeofday(tv, NULL) < 0) {
459 		log_err("gettimeofday: %s", strerror(errno));
460 	}
461 #ifndef S_SPLINT_S
462 	*tt = tv->tv_sec;
463 #endif
464 #endif /* USE_MINI_EVENT */
465 }
466 
467