1 /*	$NetBSD: ev_timers.c,v 1.11 2012/03/21 00:34:54 christos Exp $	*/
2 
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 #include <sys/cdefs.h>
25 #if !defined(LINT) && !defined(CODECENTER) && !defined(lint)
26 #ifdef notdef
27 static const char rcsid[] = "Id: ev_timers.c,v 1.6 2005/04/27 04:56:36 sra Exp";
28 #else
29 __RCSID("$NetBSD: ev_timers.c,v 1.11 2012/03/21 00:34:54 christos Exp $");
30 #endif
31 #endif
32 
33 /* Import. */
34 
35 #include "port_before.h"
36 #include "fd_setsize.h"
37 
38 #include <errno.h>
39 
40 #include <isc/assertions.h>
41 #include <isc/eventlib.h>
42 #include "eventlib_p.h"
43 
44 #include "port_after.h"
45 
46 /* Constants. */
47 
48 #define	MILLION 1000000
49 #define BILLION 1000000000
50 
51 /* Forward. */
52 
53 #ifndef _LIBC
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
evConsTime(time_t sec,long nsec)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
evAddTime(struct timespec addend1,struct timespec addend2)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
evSubTime(struct timespec minuend,struct timespec subtrahend)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
evCmpTime(struct timespec a,struct timespec b)110 evCmpTime(struct timespec a, struct timespec b) {
111 #define SGN(x) ((x) < 0 ? (-1) : (x) > 0 ? (1) : (0));
112 	time_t s = a.tv_sec - b.tv_sec;
113 	long n;
114 
115 	if (s != 0)
116 		return SGN(s);
117 
118 	n = a.tv_nsec - b.tv_nsec;
119 	return SGN(n);
120 }
121 
122 struct timespec
evNowTime(void)123 evNowTime(void)
124 {
125 	struct timeval now;
126 #ifdef CLOCK_REALTIME
127 	struct timespec tsnow;
128 	int m = CLOCK_REALTIME;
129 
130 #ifdef CLOCK_MONOTONIC
131 #ifndef _LIBC
132 	if (__evOptMonoTime)
133 		m = CLOCK_MONOTONIC;
134 #endif
135 #endif
136 	if (clock_gettime(m, &tsnow) == 0)
137 		return (tsnow);
138 #endif
139 	if (gettimeofday(&now, NULL) < 0)
140 		return (evConsTime((time_t)0, 0L));
141 	return (evTimeSpec(now));
142 }
143 
144 struct timespec
evUTCTime(void)145 evUTCTime(void) {
146 	struct timeval now;
147 #ifdef CLOCK_REALTIME
148 	struct timespec tsnow;
149 	if (clock_gettime(CLOCK_REALTIME, &tsnow) == 0)
150 		return (tsnow);
151 #endif
152 	if (gettimeofday(&now, NULL) < 0)
153 		return (evConsTime((time_t)0, 0L));
154 	return (evTimeSpec(now));
155 }
156 
157 #ifndef _LIBC
158 struct timespec
evLastEventTime(evContext opaqueCtx)159 evLastEventTime(evContext opaqueCtx) {
160 	evContext_p *ctx = opaqueCtx.opaque;
161 
162 	return (ctx->lastEventTime);
163 }
164 #endif
165 
166 struct timespec
evTimeSpec(struct timeval tv)167 evTimeSpec(struct timeval tv) {
168 	struct timespec ts;
169 
170 	ts.tv_sec = tv.tv_sec;
171 	ts.tv_nsec = tv.tv_usec * 1000;
172 	return (ts);
173 }
174 
175 struct timeval
evTimeVal(struct timespec ts)176 evTimeVal(struct timespec ts) {
177 	struct timeval tv;
178 
179 	tv.tv_sec = ts.tv_sec;
180 	tv.tv_usec = (suseconds_t)(ts.tv_nsec / 1000);
181 	return (tv);
182 }
183 
184 #ifndef _LIBC
185 int
evSetTimer(evContext opaqueCtx,evTimerFunc func,void * uap,struct timespec due,struct timespec inter,evTimerID * opaqueID)186 evSetTimer(evContext opaqueCtx,
187 	   evTimerFunc func,
188 	   void *uap,
189 	   struct timespec due,
190 	   struct timespec inter,
191 	   evTimerID *opaqueID
192 ) {
193 	evContext_p *ctx = opaqueCtx.opaque;
194 	evTimer *id;
195 
196 	evPrintf(ctx, 1,
197 "evSetTimer(ctx %p, func %p, uap %p, due %ld.%09ld, inter %ld.%09ld)\n",
198 		 ctx, func, uap,
199 		 (long)due.tv_sec, due.tv_nsec,
200 		 (long)inter.tv_sec, inter.tv_nsec);
201 
202 #ifdef __hpux
203 	/*
204 	 * tv_sec and tv_nsec are unsigned.
205 	 */
206 	if (due.tv_nsec >= BILLION)
207 		EV_ERR(EINVAL);
208 
209 	if (inter.tv_nsec >= BILLION)
210 		EV_ERR(EINVAL);
211 #else
212 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
213 		EV_ERR(EINVAL);
214 
215 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
216 		EV_ERR(EINVAL);
217 #endif
218 
219 	/* due={0,0} is a magic cookie meaning "now." */
220 	if (due.tv_sec == (time_t)0 && due.tv_nsec == 0L)
221 		due = evNowTime();
222 
223 	/* Allocate and fill. */
224 	OKNEW(id);
225 	id->func = func;
226 	id->uap = uap;
227 	id->due = due;
228 	id->inter = inter;
229 
230 	if (heap_insert(ctx->timers, id) < 0)
231 		return (-1);
232 
233 	/* Remember the ID if the caller provided us a place for it. */
234 	if (opaqueID)
235 		opaqueID->opaque = id;
236 
237 	if (ctx->debug > 7) {
238 		evPrintf(ctx, 7, "timers after evSetTimer:\n");
239 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
240 	}
241 
242 	return (0);
243 }
244 
245 int
evClearTimer(evContext opaqueCtx,evTimerID id)246 evClearTimer(evContext opaqueCtx, evTimerID id) {
247 	evContext_p *ctx = opaqueCtx.opaque;
248 	evTimer *del = id.opaque;
249 
250 	if (ctx->cur != NULL &&
251 	    ctx->cur->type == Timer &&
252 	    ctx->cur->u.timer.this == del) {
253 		evPrintf(ctx, 8, "deferring delete of timer (executing)\n");
254 		/*
255 		 * Setting the interval to zero ensures that evDrop() will
256 		 * clean up the timer.
257 		 */
258 		del->inter = evConsTime(0, 0);
259 		return (0);
260 	}
261 
262 	if (heap_element(ctx->timers, del->index) != del)
263 		EV_ERR(ENOENT);
264 
265 	if (heap_delete(ctx->timers, del->index) < 0)
266 		return (-1);
267 	FREE(del);
268 
269 	if (ctx->debug > 7) {
270 		evPrintf(ctx, 7, "timers after evClearTimer:\n");
271 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
272 	}
273 
274 	return (0);
275 }
276 
277 int
evConfigTimer(evContext opaqueCtx,evTimerID id,const char * param,int value)278 evConfigTimer(evContext opaqueCtx,
279 	     evTimerID id,
280 	     const char *param,
281 	     int value
282 ) {
283 	evContext_p *ctx = opaqueCtx.opaque;
284 	evTimer *timer = id.opaque;
285 	int result=0;
286 
287 	UNUSED(value);
288 
289 	if (heap_element(ctx->timers, timer->index) != timer)
290 		EV_ERR(ENOENT);
291 
292 	if (strcmp(param, "rate") == 0)
293 		timer->mode |= EV_TMR_RATE;
294 	else if (strcmp(param, "interval") == 0)
295 		timer->mode &= ~EV_TMR_RATE;
296 	else
297 		EV_ERR(EINVAL);
298 
299 	return (result);
300 }
301 
302 int
evResetTimer(evContext opaqueCtx,evTimerID id,evTimerFunc func,void * uap,struct timespec due,struct timespec inter)303 evResetTimer(evContext opaqueCtx,
304 	     evTimerID id,
305 	     evTimerFunc func,
306 	     void *uap,
307 	     struct timespec due,
308 	     struct timespec inter
309 ) {
310 	evContext_p *ctx = opaqueCtx.opaque;
311 	evTimer *timer = id.opaque;
312 	struct timespec old_due;
313 	int result=0;
314 
315 	if (heap_element(ctx->timers, timer->index) != timer)
316 		EV_ERR(ENOENT);
317 
318 #ifdef __hpux
319 	/*
320 	 * tv_sec and tv_nsec are unsigned.
321 	 */
322 	if (due.tv_nsec >= BILLION)
323 		EV_ERR(EINVAL);
324 
325 	if (inter.tv_nsec >= BILLION)
326 		EV_ERR(EINVAL);
327 #else
328 	if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
329 		EV_ERR(EINVAL);
330 
331 	if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
332 		EV_ERR(EINVAL);
333 #endif
334 
335 	old_due = timer->due;
336 
337 	timer->func = func;
338 	timer->uap = uap;
339 	timer->due = due;
340 	timer->inter = inter;
341 
342 	switch (evCmpTime(due, old_due)) {
343 	case -1:
344 		result = heap_increased(ctx->timers, timer->index);
345 		break;
346 	case 0:
347 		result = 0;
348 		break;
349 	case 1:
350 		result = heap_decreased(ctx->timers, timer->index);
351 		break;
352 	}
353 
354 	if (ctx->debug > 7) {
355 		evPrintf(ctx, 7, "timers after evResetTimer:\n");
356 		(void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
357 	}
358 
359 	return (result);
360 }
361 
362 int
evSetIdleTimer(evContext opaqueCtx,evTimerFunc func,void * uap,struct timespec max_idle,evTimerID * opaqueID)363 evSetIdleTimer(evContext opaqueCtx,
364 		evTimerFunc func,
365 		void *uap,
366 		struct timespec max_idle,
367 		evTimerID *opaqueID
368 ) {
369 	evContext_p *ctx = opaqueCtx.opaque;
370 	idle_timer *tt;
371 
372 	/* Allocate and fill. */
373 	OKNEW(tt);
374 	tt->func = func;
375 	tt->uap = uap;
376 	tt->lastTouched = ctx->lastEventTime;
377 	tt->max_idle = max_idle;
378 
379 	if (evSetTimer(opaqueCtx, idle_timeout, tt,
380 		       evAddTime(ctx->lastEventTime, max_idle),
381 		       max_idle, opaqueID) < 0) {
382 		FREE(tt);
383 		return (-1);
384 	}
385 
386 	tt->timer = opaqueID->opaque;
387 
388 	return (0);
389 }
390 
391 int
evClearIdleTimer(evContext opaqueCtx,evTimerID id)392 evClearIdleTimer(evContext opaqueCtx, evTimerID id) {
393 	evTimer *del = id.opaque;
394 	idle_timer *tt = del->uap;
395 
396 	FREE(tt);
397 	return (evClearTimer(opaqueCtx, id));
398 }
399 
400 int
evResetIdleTimer(evContext opaqueCtx,evTimerID opaqueID,evTimerFunc func,void * uap,struct timespec max_idle)401 evResetIdleTimer(evContext opaqueCtx,
402 		 evTimerID opaqueID,
403 		 evTimerFunc func,
404 		 void *uap,
405 		 struct timespec max_idle
406 ) {
407 	evContext_p *ctx = opaqueCtx.opaque;
408 	evTimer *timer = opaqueID.opaque;
409 	idle_timer *tt = timer->uap;
410 
411 	tt->func = func;
412 	tt->uap = uap;
413 	tt->lastTouched = ctx->lastEventTime;
414 	tt->max_idle = max_idle;
415 
416 	return (evResetTimer(opaqueCtx, opaqueID, idle_timeout, tt,
417 			     evAddTime(ctx->lastEventTime, max_idle),
418 			     max_idle));
419 }
420 
421 int
evTouchIdleTimer(evContext opaqueCtx,evTimerID id)422 evTouchIdleTimer(evContext opaqueCtx, evTimerID id) {
423 	evContext_p *ctx = opaqueCtx.opaque;
424 	evTimer *t = id.opaque;
425 	idle_timer *tt = t->uap;
426 
427 	tt->lastTouched = ctx->lastEventTime;
428 
429 	return (0);
430 }
431 
432 /* Public to the rest of eventlib. */
433 
434 heap_context
evCreateTimers(const evContext_p * ctx)435 evCreateTimers(const evContext_p *ctx) {
436 
437 	UNUSED(ctx);
438 
439 	return (heap_new(due_sooner, set_index, 2048));
440 }
441 
442 void
evDestroyTimers(const evContext_p * ctx)443 evDestroyTimers(const evContext_p *ctx) {
444 	(void) heap_for_each(ctx->timers, free_timer, NULL);
445 	(void) heap_free(ctx->timers);
446 }
447 
448 /* Private. */
449 
450 static int
due_sooner(void * a,void * b)451 due_sooner(void *a, void *b) {
452 	evTimer *a_timer, *b_timer;
453 
454 	a_timer = a;
455 	b_timer = b;
456 	return (evCmpTime(a_timer->due, b_timer->due) < 0);
457 }
458 
459 static void
set_index(void * what,int idx)460 set_index(void *what, int idx) {
461 	evTimer *timer;
462 
463 	timer = what;
464 	timer->index = idx;
465 }
466 
467 static void
free_timer(void * what,void * uap)468 free_timer(void *what, void *uap) {
469 	evTimer *t = what;
470 
471 	UNUSED(uap);
472 
473 	FREE(t);
474 }
475 
476 static void
print_timer(void * what,void * uap)477 print_timer(void *what, void *uap) {
478 	evTimer *cur = what;
479 	evContext_p *ctx = uap;
480 
481 	cur = what;
482 	evPrintf(ctx, 7,
483 	    "  func %p, uap %p, due %ld.%09ld, inter %ld.%09ld\n",
484 		 cur->func, cur->uap,
485 		 (long)cur->due.tv_sec, cur->due.tv_nsec,
486 		 (long)cur->inter.tv_sec, cur->inter.tv_nsec);
487 }
488 
489 static void
idle_timeout(evContext opaqueCtx,void * uap,struct timespec due,struct timespec inter)490 idle_timeout(evContext opaqueCtx,
491 	     void *uap,
492 	     struct timespec due,
493 	     struct timespec inter
494 ) {
495 	evContext_p *ctx = opaqueCtx.opaque;
496 	idle_timer *this = uap;
497 	struct timespec idle;
498 
499 	UNUSED(due);
500 	UNUSED(inter);
501 
502 	idle = evSubTime(ctx->lastEventTime, this->lastTouched);
503 	if (evCmpTime(idle, this->max_idle) >= 0) {
504 		(this->func)(opaqueCtx, this->uap, this->timer->due,
505 			     this->max_idle);
506 		/*
507 		 * Setting the interval to zero will cause the timer to
508 		 * be cleaned up in evDrop().
509 		 */
510 		this->timer->inter = evConsTime(0L, 0L);
511 		FREE(this);
512 	} else {
513 		/* evDrop() will reschedule the timer. */
514 		this->timer->inter = evSubTime(this->max_idle, idle);
515 	}
516 }
517 #endif
518 
519 /*! \file */
520