xref: /freebsd/lib/libc/isc/ev_timers.c (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
1 /*-
2  * SPDX-License-Identifier: ISC
3  *
4  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5  * Copyright (c) 1995-1999 by Internet Software Consortium
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 /* ev_timers.c - implement timers for the eventlib
21  * vix 09sep95 [initial]
22  */
23 
24 #if !defined(LINT) && !defined(CODECENTER)
25 static const char rcsid[] = "$Id: ev_timers.c,v 1.6 2005/04/27 04:56:36 sra Exp $";
26 #endif
27 /* Import. */
28 
29 #include "port_before.h"
30 #ifndef _LIBC
31 #include "fd_setsize.h"
32 #endif
33 
34 #include <errno.h>
35 
36 #ifndef _LIBC
37 #include <isc/assertions.h>
38 #endif
39 #include <isc/eventlib.h>
40 #include "eventlib_p.h"
41 
42 #include "port_after.h"
43 
44 /* Constants. */
45 
46 #define	MILLION 1000000
47 #define BILLION 1000000000
48 
49 /* Forward. */
50 
51 #ifdef _LIBC
52 static int	__evOptMonoTime;
53 #else
54 static int due_sooner(void *, void *);
55 static void set_index(void *, int);
56 static void free_timer(void *, void *);
57 static void print_timer(void *, void *);
58 static void idle_timeout(evContext, void *, struct timespec, struct timespec);
59 
60 /* Private type. */
61 
62 typedef struct {
63 	evTimerFunc	func;
64 	void *		uap;
65 	struct timespec	lastTouched;
66 	struct timespec	max_idle;
67 	evTimer *	timer;
68 } idle_timer;
69 #endif
70 
71 /* Public. */
72 
73 struct timespec
74 evConsTime(time_t sec, long nsec) {
75 	struct timespec x;
76 
77 	x.tv_sec = sec;
78 	x.tv_nsec = nsec;
79 	return (x);
80 }
81 
82 struct timespec
83 evAddTime(struct timespec addend1, struct timespec addend2) {
84 	struct timespec x;
85 
86 	x.tv_sec = addend1.tv_sec + addend2.tv_sec;
87 	x.tv_nsec = addend1.tv_nsec + addend2.tv_nsec;
88 	if (x.tv_nsec >= BILLION) {
89 		x.tv_sec++;
90 		x.tv_nsec -= BILLION;
91 	}
92 	return (x);
93 }
94 
95 struct timespec
96 evSubTime(struct timespec minuend, struct timespec subtrahend) {
97 	struct timespec x;
98 
99 	x.tv_sec = minuend.tv_sec - subtrahend.tv_sec;
100 	if (minuend.tv_nsec >= subtrahend.tv_nsec)
101 		x.tv_nsec = minuend.tv_nsec - subtrahend.tv_nsec;
102 	else {
103 		x.tv_nsec = BILLION - subtrahend.tv_nsec + minuend.tv_nsec;
104 		x.tv_sec--;
105 	}
106 	return (x);
107 }
108 
109 int
110 evCmpTime(struct timespec a, struct timespec b) {
111 	long x = a.tv_sec - b.tv_sec;
112 
113 	if (x == 0L)
114 		x = a.tv_nsec - b.tv_nsec;
115 	return (x < 0L ? (-1) : x > 0L ? (1) : (0));
116 }
117 
118 struct timespec
119 evNowTime(void) {
120 	struct timeval now;
121 #ifdef CLOCK_REALTIME
122 	struct timespec tsnow;
123 	int m = CLOCK_REALTIME;
124 
125 #ifdef CLOCK_MONOTONIC
126 	if (__evOptMonoTime)
127 		m = CLOCK_MONOTONIC;
128 #endif
129 	if (clock_gettime(m, &tsnow) == 0)
130 		return (tsnow);
131 #endif
132 	if (gettimeofday(&now, NULL) < 0)
133 		return (evConsTime(0, 0));
134 	return (evTimeSpec(now));
135 }
136 
137 struct timespec
138 evUTCTime(void) {
139 	struct timeval now;
140 #ifdef CLOCK_REALTIME
141 	struct timespec tsnow;
142 	if (clock_gettime(CLOCK_REALTIME, &tsnow) == 0)
143 		return (tsnow);
144 #endif
145 	if (gettimeofday(&now, NULL) < 0)
146 		return (evConsTime(0, 0));
147 	return (evTimeSpec(now));
148 }
149 
150 #ifndef _LIBC
151 struct timespec
152 evLastEventTime(evContext opaqueCtx) {
153 	evContext_p *ctx = opaqueCtx.opaque;
154 
155 	return (ctx->lastEventTime);
156 }
157 #endif
158 
159 struct timespec
160 evTimeSpec(struct timeval tv) {
161 	struct timespec ts;
162 
163 	ts.tv_sec = tv.tv_sec;
164 	ts.tv_nsec = tv.tv_usec * 1000;
165 	return (ts);
166 }
167 
168 #if !defined(USE_KQUEUE) || !defined(_LIBC)
169 struct timeval
170 evTimeVal(struct timespec ts) {
171 	struct timeval tv;
172 
173 	tv.tv_sec = ts.tv_sec;
174 	tv.tv_usec = ts.tv_nsec / 1000;
175 	return (tv);
176 }
177 #endif
178 
179 #ifndef _LIBC
180 int
181 evSetTimer(evContext opaqueCtx,
182 	   evTimerFunc func,
183 	   void *uap,
184 	   struct timespec due,
185 	   struct timespec inter,
186 	   evTimerID *opaqueID
187 ) {
188 	evContext_p *ctx = opaqueCtx.opaque;
189 	evTimer *id;
190 
191 	evPrintf(ctx, 1,
192 "evSetTimer(ctx %p, func %p, uap %p, due %ld.%09ld, inter %ld.%09ld)\n",
193 		 ctx, func, uap,
194 		 (long)due.tv_sec, due.tv_nsec,
195 		 (long)inter.tv_sec, inter.tv_nsec);
196 
197 #ifdef __hpux
198 	/*
199 	 * tv_sec and tv_nsec are unsigned.
200 	 */
201 	if (due.tv_nsec >= BILLION)
202 		EV_ERR(EINVAL);
203 
204 	if (inter.tv_nsec >= BILLION)
205 		EV_ERR(EINVAL);
206 #else
207 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
208 		EV_ERR(EINVAL);
209 
210 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
211 		EV_ERR(EINVAL);
212 #endif
213 
214 	/* due={0,0} is a magic cookie meaning "now." */
215 	if (due.tv_sec == (time_t)0 && due.tv_nsec == 0L)
216 		due = evNowTime();
217 
218 	/* Allocate and fill. */
219 	OKNEW(id);
220 	id->func = func;
221 	id->uap = uap;
222 	id->due = due;
223 	id->inter = inter;
224 
225 	if (heap_insert(ctx->timers, id) < 0)
226 		return (-1);
227 
228 	/* Remember the ID if the caller provided us a place for it. */
229 	if (opaqueID)
230 		opaqueID->opaque = id;
231 
232 	if (ctx->debug > 7) {
233 		evPrintf(ctx, 7, "timers after evSetTimer:\n");
234 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
235 	}
236 
237 	return (0);
238 }
239 
240 int
241 evClearTimer(evContext opaqueCtx, evTimerID id) {
242 	evContext_p *ctx = opaqueCtx.opaque;
243 	evTimer *del = id.opaque;
244 
245 	if (ctx->cur != NULL &&
246 	    ctx->cur->type == Timer &&
247 	    ctx->cur->u.timer.this == del) {
248 		evPrintf(ctx, 8, "deferring delete of timer (executing)\n");
249 		/*
250 		 * Setting the interval to zero ensures that evDrop() will
251 		 * clean up the timer.
252 		 */
253 		del->inter = evConsTime(0, 0);
254 		return (0);
255 	}
256 
257 	if (heap_element(ctx->timers, del->index) != del)
258 		EV_ERR(ENOENT);
259 
260 	if (heap_delete(ctx->timers, del->index) < 0)
261 		return (-1);
262 	FREE(del);
263 
264 	if (ctx->debug > 7) {
265 		evPrintf(ctx, 7, "timers after evClearTimer:\n");
266 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
267 	}
268 
269 	return (0);
270 }
271 
272 int
273 evConfigTimer(evContext opaqueCtx,
274 	     evTimerID id,
275 	     const char *param,
276 	     int value
277 ) {
278 	evContext_p *ctx = opaqueCtx.opaque;
279 	evTimer *timer = id.opaque;
280 	int result=0;
281 
282 	UNUSED(value);
283 
284 	if (heap_element(ctx->timers, timer->index) != timer)
285 		EV_ERR(ENOENT);
286 
287 	if (strcmp(param, "rate") == 0)
288 		timer->mode |= EV_TMR_RATE;
289 	else if (strcmp(param, "interval") == 0)
290 		timer->mode &= ~EV_TMR_RATE;
291 	else
292 		EV_ERR(EINVAL);
293 
294 	return (result);
295 }
296 
297 int
298 evResetTimer(evContext opaqueCtx,
299 	     evTimerID id,
300 	     evTimerFunc func,
301 	     void *uap,
302 	     struct timespec due,
303 	     struct timespec inter
304 ) {
305 	evContext_p *ctx = opaqueCtx.opaque;
306 	evTimer *timer = id.opaque;
307 	struct timespec old_due;
308 	int result=0;
309 
310 	if (heap_element(ctx->timers, timer->index) != timer)
311 		EV_ERR(ENOENT);
312 
313 #ifdef __hpux
314 	/*
315 	 * tv_sec and tv_nsec are unsigned.
316 	 */
317 	if (due.tv_nsec >= BILLION)
318 		EV_ERR(EINVAL);
319 
320 	if (inter.tv_nsec >= BILLION)
321 		EV_ERR(EINVAL);
322 #else
323 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
324 		EV_ERR(EINVAL);
325 
326 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
327 		EV_ERR(EINVAL);
328 #endif
329 
330 	old_due = timer->due;
331 
332 	timer->func = func;
333 	timer->uap = uap;
334 	timer->due = due;
335 	timer->inter = inter;
336 
337 	switch (evCmpTime(due, old_due)) {
338 	case -1:
339 		result = heap_increased(ctx->timers, timer->index);
340 		break;
341 	case 0:
342 		result = 0;
343 		break;
344 	case 1:
345 		result = heap_decreased(ctx->timers, timer->index);
346 		break;
347 	}
348 
349 	if (ctx->debug > 7) {
350 		evPrintf(ctx, 7, "timers after evResetTimer:\n");
351 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
352 	}
353 
354 	return (result);
355 }
356 
357 int
358 evSetIdleTimer(evContext opaqueCtx,
359 		evTimerFunc func,
360 		void *uap,
361 		struct timespec max_idle,
362 		evTimerID *opaqueID
363 ) {
364 	evContext_p *ctx = opaqueCtx.opaque;
365 	idle_timer *tt;
366 
367 	/* Allocate and fill. */
368 	OKNEW(tt);
369 	tt->func = func;
370 	tt->uap = uap;
371 	tt->lastTouched = ctx->lastEventTime;
372 	tt->max_idle = max_idle;
373 
374 	if (evSetTimer(opaqueCtx, idle_timeout, tt,
375 		       evAddTime(ctx->lastEventTime, max_idle),
376 		       max_idle, opaqueID) < 0) {
377 		FREE(tt);
378 		return (-1);
379 	}
380 
381 	tt->timer = opaqueID->opaque;
382 
383 	return (0);
384 }
385 
386 int
387 evClearIdleTimer(evContext opaqueCtx, evTimerID id) {
388 	evTimer *del = id.opaque;
389 	idle_timer *tt = del->uap;
390 
391 	FREE(tt);
392 	return (evClearTimer(opaqueCtx, id));
393 }
394 
395 int
396 evResetIdleTimer(evContext opaqueCtx,
397 		 evTimerID opaqueID,
398 		 evTimerFunc func,
399 		 void *uap,
400 		 struct timespec max_idle
401 ) {
402 	evContext_p *ctx = opaqueCtx.opaque;
403 	evTimer *timer = opaqueID.opaque;
404 	idle_timer *tt = timer->uap;
405 
406 	tt->func = func;
407 	tt->uap = uap;
408 	tt->lastTouched = ctx->lastEventTime;
409 	tt->max_idle = max_idle;
410 
411 	return (evResetTimer(opaqueCtx, opaqueID, idle_timeout, tt,
412 			     evAddTime(ctx->lastEventTime, max_idle),
413 			     max_idle));
414 }
415 
416 int
417 evTouchIdleTimer(evContext opaqueCtx, evTimerID id) {
418 	evContext_p *ctx = opaqueCtx.opaque;
419 	evTimer *t = id.opaque;
420 	idle_timer *tt = t->uap;
421 
422 	tt->lastTouched = ctx->lastEventTime;
423 
424 	return (0);
425 }
426 
427 /* Public to the rest of eventlib. */
428 
429 heap_context
430 evCreateTimers(const evContext_p *ctx) {
431 
432 	UNUSED(ctx);
433 
434 	return (heap_new(due_sooner, set_index, 2048));
435 }
436 
437 void
438 evDestroyTimers(const evContext_p *ctx) {
439 	(void) heap_for_each(ctx->timers, free_timer, NULL);
440 	(void) heap_free(ctx->timers);
441 }
442 
443 /* Private. */
444 
445 static int
446 due_sooner(void *a, void *b) {
447 	evTimer *a_timer, *b_timer;
448 
449 	a_timer = a;
450 	b_timer = b;
451 	return (evCmpTime(a_timer->due, b_timer->due) < 0);
452 }
453 
454 static void
455 set_index(void *what, int index) {
456 	evTimer *timer;
457 
458 	timer = what;
459 	timer->index = index;
460 }
461 
462 static void
463 free_timer(void *what, void *uap) {
464 	evTimer *t = what;
465 
466 	UNUSED(uap);
467 
468 	FREE(t);
469 }
470 
471 static void
472 print_timer(void *what, void *uap) {
473 	evTimer *cur = what;
474 	evContext_p *ctx = uap;
475 
476 	cur = what;
477 	evPrintf(ctx, 7,
478 	    "  func %p, uap %p, due %ld.%09ld, inter %ld.%09ld\n",
479 		 cur->func, cur->uap,
480 		 (long)cur->due.tv_sec, cur->due.tv_nsec,
481 		 (long)cur->inter.tv_sec, cur->inter.tv_nsec);
482 }
483 
484 static void
485 idle_timeout(evContext opaqueCtx,
486 	     void *uap,
487 	     struct timespec due,
488 	     struct timespec inter
489 ) {
490 	evContext_p *ctx = opaqueCtx.opaque;
491 	idle_timer *this = uap;
492 	struct timespec idle;
493 
494 	UNUSED(due);
495 	UNUSED(inter);
496 
497 	idle = evSubTime(ctx->lastEventTime, this->lastTouched);
498 	if (evCmpTime(idle, this->max_idle) >= 0) {
499 		(this->func)(opaqueCtx, this->uap, this->timer->due,
500 			     this->max_idle);
501 		/*
502 		 * Setting the interval to zero will cause the timer to
503 		 * be cleaned up in evDrop().
504 		 */
505 		this->timer->inter = evConsTime(0, 0);
506 		FREE(this);
507 	} else {
508 		/* evDrop() will reschedule the timer. */
509 		this->timer->inter = evSubTime(this->max_idle, idle);
510 	}
511 }
512 #endif
513 
514 /*! \file */
515