xref: /freebsd/lib/libc/isc/ev_timers.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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 /* Import. */
25 
26 #include "port_before.h"
27 #ifndef _LIBC
28 #include "fd_setsize.h"
29 #endif
30 
31 #include <errno.h>
32 
33 #ifndef _LIBC
34 #include <isc/assertions.h>
35 #endif
36 #include <isc/eventlib.h>
37 #include "eventlib_p.h"
38 
39 #include "port_after.h"
40 
41 /* Constants. */
42 
43 #define	MILLION 1000000
44 #define BILLION 1000000000
45 
46 /* Forward. */
47 
48 #ifdef _LIBC
49 static int	__evOptMonoTime;
50 #else
51 static int due_sooner(void *, void *);
52 static void set_index(void *, int);
53 static void free_timer(void *, void *);
54 static void print_timer(void *, void *);
55 static void idle_timeout(evContext, void *, struct timespec, struct timespec);
56 
57 /* Private type. */
58 
59 typedef struct {
60 	evTimerFunc	func;
61 	void *		uap;
62 	struct timespec	lastTouched;
63 	struct timespec	max_idle;
64 	evTimer *	timer;
65 } idle_timer;
66 #endif
67 
68 /* Public. */
69 
70 struct timespec
71 evConsTime(time_t sec, long nsec) {
72 	struct timespec x;
73 
74 	x.tv_sec = sec;
75 	x.tv_nsec = nsec;
76 	return (x);
77 }
78 
79 struct timespec
80 evAddTime(struct timespec addend1, struct timespec addend2) {
81 	struct timespec x;
82 
83 	x.tv_sec = addend1.tv_sec + addend2.tv_sec;
84 	x.tv_nsec = addend1.tv_nsec + addend2.tv_nsec;
85 	if (x.tv_nsec >= BILLION) {
86 		x.tv_sec++;
87 		x.tv_nsec -= BILLION;
88 	}
89 	return (x);
90 }
91 
92 struct timespec
93 evSubTime(struct timespec minuend, struct timespec subtrahend) {
94 	struct timespec x;
95 
96 	x.tv_sec = minuend.tv_sec - subtrahend.tv_sec;
97 	if (minuend.tv_nsec >= subtrahend.tv_nsec)
98 		x.tv_nsec = minuend.tv_nsec - subtrahend.tv_nsec;
99 	else {
100 		x.tv_nsec = BILLION - subtrahend.tv_nsec + minuend.tv_nsec;
101 		x.tv_sec--;
102 	}
103 	return (x);
104 }
105 
106 int
107 evCmpTime(struct timespec a, struct timespec b) {
108 	long x = a.tv_sec - b.tv_sec;
109 
110 	if (x == 0L)
111 		x = a.tv_nsec - b.tv_nsec;
112 	return (x < 0L ? (-1) : x > 0L ? (1) : (0));
113 }
114 
115 struct timespec
116 evNowTime(void) {
117 	struct timeval now;
118 #ifdef CLOCK_REALTIME
119 	struct timespec tsnow;
120 	int m = CLOCK_REALTIME;
121 
122 #ifdef CLOCK_MONOTONIC
123 	if (__evOptMonoTime)
124 		m = CLOCK_MONOTONIC;
125 #endif
126 	if (clock_gettime(m, &tsnow) == 0)
127 		return (tsnow);
128 #endif
129 	if (gettimeofday(&now, NULL) < 0)
130 		return (evConsTime(0, 0));
131 	return (evTimeSpec(now));
132 }
133 
134 struct timespec
135 evUTCTime(void) {
136 	struct timeval now;
137 #ifdef CLOCK_REALTIME
138 	struct timespec tsnow;
139 	if (clock_gettime(CLOCK_REALTIME, &tsnow) == 0)
140 		return (tsnow);
141 #endif
142 	if (gettimeofday(&now, NULL) < 0)
143 		return (evConsTime(0, 0));
144 	return (evTimeSpec(now));
145 }
146 
147 #ifndef _LIBC
148 struct timespec
149 evLastEventTime(evContext opaqueCtx) {
150 	evContext_p *ctx = opaqueCtx.opaque;
151 
152 	return (ctx->lastEventTime);
153 }
154 #endif
155 
156 struct timespec
157 evTimeSpec(struct timeval tv) {
158 	struct timespec ts;
159 
160 	ts.tv_sec = tv.tv_sec;
161 	ts.tv_nsec = tv.tv_usec * 1000;
162 	return (ts);
163 }
164 
165 #if !defined(USE_KQUEUE) || !defined(_LIBC)
166 struct timeval
167 evTimeVal(struct timespec ts) {
168 	struct timeval tv;
169 
170 	tv.tv_sec = ts.tv_sec;
171 	tv.tv_usec = ts.tv_nsec / 1000;
172 	return (tv);
173 }
174 #endif
175 
176 #ifndef _LIBC
177 int
178 evSetTimer(evContext opaqueCtx,
179 	   evTimerFunc func,
180 	   void *uap,
181 	   struct timespec due,
182 	   struct timespec inter,
183 	   evTimerID *opaqueID
184 ) {
185 	evContext_p *ctx = opaqueCtx.opaque;
186 	evTimer *id;
187 
188 	evPrintf(ctx, 1,
189 "evSetTimer(ctx %p, func %p, uap %p, due %ld.%09ld, inter %ld.%09ld)\n",
190 		 ctx, func, uap,
191 		 (long)due.tv_sec, due.tv_nsec,
192 		 (long)inter.tv_sec, inter.tv_nsec);
193 
194 #ifdef __hpux
195 	/*
196 	 * tv_sec and tv_nsec are unsigned.
197 	 */
198 	if (due.tv_nsec >= BILLION)
199 		EV_ERR(EINVAL);
200 
201 	if (inter.tv_nsec >= BILLION)
202 		EV_ERR(EINVAL);
203 #else
204 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
205 		EV_ERR(EINVAL);
206 
207 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
208 		EV_ERR(EINVAL);
209 #endif
210 
211 	/* due={0,0} is a magic cookie meaning "now." */
212 	if (due.tv_sec == (time_t)0 && due.tv_nsec == 0L)
213 		due = evNowTime();
214 
215 	/* Allocate and fill. */
216 	OKNEW(id);
217 	id->func = func;
218 	id->uap = uap;
219 	id->due = due;
220 	id->inter = inter;
221 
222 	if (heap_insert(ctx->timers, id) < 0)
223 		return (-1);
224 
225 	/* Remember the ID if the caller provided us a place for it. */
226 	if (opaqueID)
227 		opaqueID->opaque = id;
228 
229 	if (ctx->debug > 7) {
230 		evPrintf(ctx, 7, "timers after evSetTimer:\n");
231 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
232 	}
233 
234 	return (0);
235 }
236 
237 int
238 evClearTimer(evContext opaqueCtx, evTimerID id) {
239 	evContext_p *ctx = opaqueCtx.opaque;
240 	evTimer *del = id.opaque;
241 
242 	if (ctx->cur != NULL &&
243 	    ctx->cur->type == Timer &&
244 	    ctx->cur->u.timer.this == del) {
245 		evPrintf(ctx, 8, "deferring delete of timer (executing)\n");
246 		/*
247 		 * Setting the interval to zero ensures that evDrop() will
248 		 * clean up the timer.
249 		 */
250 		del->inter = evConsTime(0, 0);
251 		return (0);
252 	}
253 
254 	if (heap_element(ctx->timers, del->index) != del)
255 		EV_ERR(ENOENT);
256 
257 	if (heap_delete(ctx->timers, del->index) < 0)
258 		return (-1);
259 	FREE(del);
260 
261 	if (ctx->debug > 7) {
262 		evPrintf(ctx, 7, "timers after evClearTimer:\n");
263 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
264 	}
265 
266 	return (0);
267 }
268 
269 int
270 evConfigTimer(evContext opaqueCtx,
271 	     evTimerID id,
272 	     const char *param,
273 	     int value
274 ) {
275 	evContext_p *ctx = opaqueCtx.opaque;
276 	evTimer *timer = id.opaque;
277 	int result=0;
278 
279 	UNUSED(value);
280 
281 	if (heap_element(ctx->timers, timer->index) != timer)
282 		EV_ERR(ENOENT);
283 
284 	if (strcmp(param, "rate") == 0)
285 		timer->mode |= EV_TMR_RATE;
286 	else if (strcmp(param, "interval") == 0)
287 		timer->mode &= ~EV_TMR_RATE;
288 	else
289 		EV_ERR(EINVAL);
290 
291 	return (result);
292 }
293 
294 int
295 evResetTimer(evContext opaqueCtx,
296 	     evTimerID id,
297 	     evTimerFunc func,
298 	     void *uap,
299 	     struct timespec due,
300 	     struct timespec inter
301 ) {
302 	evContext_p *ctx = opaqueCtx.opaque;
303 	evTimer *timer = id.opaque;
304 	struct timespec old_due;
305 	int result=0;
306 
307 	if (heap_element(ctx->timers, timer->index) != timer)
308 		EV_ERR(ENOENT);
309 
310 #ifdef __hpux
311 	/*
312 	 * tv_sec and tv_nsec are unsigned.
313 	 */
314 	if (due.tv_nsec >= BILLION)
315 		EV_ERR(EINVAL);
316 
317 	if (inter.tv_nsec >= BILLION)
318 		EV_ERR(EINVAL);
319 #else
320 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
321 		EV_ERR(EINVAL);
322 
323 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
324 		EV_ERR(EINVAL);
325 #endif
326 
327 	old_due = timer->due;
328 
329 	timer->func = func;
330 	timer->uap = uap;
331 	timer->due = due;
332 	timer->inter = inter;
333 
334 	switch (evCmpTime(due, old_due)) {
335 	case -1:
336 		result = heap_increased(ctx->timers, timer->index);
337 		break;
338 	case 0:
339 		result = 0;
340 		break;
341 	case 1:
342 		result = heap_decreased(ctx->timers, timer->index);
343 		break;
344 	}
345 
346 	if (ctx->debug > 7) {
347 		evPrintf(ctx, 7, "timers after evResetTimer:\n");
348 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
349 	}
350 
351 	return (result);
352 }
353 
354 int
355 evSetIdleTimer(evContext opaqueCtx,
356 		evTimerFunc func,
357 		void *uap,
358 		struct timespec max_idle,
359 		evTimerID *opaqueID
360 ) {
361 	evContext_p *ctx = opaqueCtx.opaque;
362 	idle_timer *tt;
363 
364 	/* Allocate and fill. */
365 	OKNEW(tt);
366 	tt->func = func;
367 	tt->uap = uap;
368 	tt->lastTouched = ctx->lastEventTime;
369 	tt->max_idle = max_idle;
370 
371 	if (evSetTimer(opaqueCtx, idle_timeout, tt,
372 		       evAddTime(ctx->lastEventTime, max_idle),
373 		       max_idle, opaqueID) < 0) {
374 		FREE(tt);
375 		return (-1);
376 	}
377 
378 	tt->timer = opaqueID->opaque;
379 
380 	return (0);
381 }
382 
383 int
384 evClearIdleTimer(evContext opaqueCtx, evTimerID id) {
385 	evTimer *del = id.opaque;
386 	idle_timer *tt = del->uap;
387 
388 	FREE(tt);
389 	return (evClearTimer(opaqueCtx, id));
390 }
391 
392 int
393 evResetIdleTimer(evContext opaqueCtx,
394 		 evTimerID opaqueID,
395 		 evTimerFunc func,
396 		 void *uap,
397 		 struct timespec max_idle
398 ) {
399 	evContext_p *ctx = opaqueCtx.opaque;
400 	evTimer *timer = opaqueID.opaque;
401 	idle_timer *tt = timer->uap;
402 
403 	tt->func = func;
404 	tt->uap = uap;
405 	tt->lastTouched = ctx->lastEventTime;
406 	tt->max_idle = max_idle;
407 
408 	return (evResetTimer(opaqueCtx, opaqueID, idle_timeout, tt,
409 			     evAddTime(ctx->lastEventTime, max_idle),
410 			     max_idle));
411 }
412 
413 int
414 evTouchIdleTimer(evContext opaqueCtx, evTimerID id) {
415 	evContext_p *ctx = opaqueCtx.opaque;
416 	evTimer *t = id.opaque;
417 	idle_timer *tt = t->uap;
418 
419 	tt->lastTouched = ctx->lastEventTime;
420 
421 	return (0);
422 }
423 
424 /* Public to the rest of eventlib. */
425 
426 heap_context
427 evCreateTimers(const evContext_p *ctx) {
428 
429 	UNUSED(ctx);
430 
431 	return (heap_new(due_sooner, set_index, 2048));
432 }
433 
434 void
435 evDestroyTimers(const evContext_p *ctx) {
436 	(void) heap_for_each(ctx->timers, free_timer, NULL);
437 	(void) heap_free(ctx->timers);
438 }
439 
440 /* Private. */
441 
442 static int
443 due_sooner(void *a, void *b) {
444 	evTimer *a_timer, *b_timer;
445 
446 	a_timer = a;
447 	b_timer = b;
448 	return (evCmpTime(a_timer->due, b_timer->due) < 0);
449 }
450 
451 static void
452 set_index(void *what, int index) {
453 	evTimer *timer;
454 
455 	timer = what;
456 	timer->index = index;
457 }
458 
459 static void
460 free_timer(void *what, void *uap) {
461 	evTimer *t = what;
462 
463 	UNUSED(uap);
464 
465 	FREE(t);
466 }
467 
468 static void
469 print_timer(void *what, void *uap) {
470 	evTimer *cur = what;
471 	evContext_p *ctx = uap;
472 
473 	cur = what;
474 	evPrintf(ctx, 7,
475 	    "  func %p, uap %p, due %ld.%09ld, inter %ld.%09ld\n",
476 		 cur->func, cur->uap,
477 		 (long)cur->due.tv_sec, cur->due.tv_nsec,
478 		 (long)cur->inter.tv_sec, cur->inter.tv_nsec);
479 }
480 
481 static void
482 idle_timeout(evContext opaqueCtx,
483 	     void *uap,
484 	     struct timespec due,
485 	     struct timespec inter
486 ) {
487 	evContext_p *ctx = opaqueCtx.opaque;
488 	idle_timer *this = uap;
489 	struct timespec idle;
490 
491 	UNUSED(due);
492 	UNUSED(inter);
493 
494 	idle = evSubTime(ctx->lastEventTime, this->lastTouched);
495 	if (evCmpTime(idle, this->max_idle) >= 0) {
496 		(this->func)(opaqueCtx, this->uap, this->timer->due,
497 			     this->max_idle);
498 		/*
499 		 * Setting the interval to zero will cause the timer to
500 		 * be cleaned up in evDrop().
501 		 */
502 		this->timer->inter = evConsTime(0, 0);
503 		FREE(this);
504 	} else {
505 		/* evDrop() will reschedule the timer. */
506 		this->timer->inter = evSubTime(this->max_idle, idle);
507 	}
508 }
509 #endif
510 
511 /*! \file */
512