lib/libc/isc/ev_timers.c

   1 /*      $NetBSD: ev_timers.c,v 1.8 2009/04/12 17:07:17 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 1.8 2009/04/12 17:07:17 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
  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 #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
 123 evNowTime() {
 124         struct timeval now;
 125 #ifdef CLOCK_REALTIME
 126         struct timespec tsnow;
 127         int m = CLOCK_REALTIME;
 128
 129 #ifdef CLOCK_MONOTONIC
 130 #ifndef _LIBC
 131         if (__evOptMonoTime)
 132                 m = CLOCK_MONOTONIC;
 133 #endif
 134 #endif
 135         if (clock_gettime(m, &tsnow) == 0)
 136                 return (tsnow);
 137 #endif
 138         if (gettimeofday(&now, NULL) < 0)
 139                 return (evConsTime(0L, 0L));
 140         return (evTimeSpec(now));
 141 }
 142
 143 struct timespec
 144 evUTCTime(void) {
 145         struct timeval now;
 146 #ifdef CLOCK_REALTIME
 147         struct timespec tsnow;
 148         if (clock_gettime(CLOCK_REALTIME, &tsnow) == 0)
 149                 return (tsnow);
 150 #endif
 151         if (gettimeofday(&now, NULL) < 0)
 152                 return (evConsTime(0L, 0L));
 153         return (evTimeSpec(now));
 154 }
 155
 156 #ifndef _LIBC
 157 struct timespec
 158 evLastEventTime(evContext opaqueCtx) {
 159         evContext_p *ctx = opaqueCtx.opaque;
 160
 161         return (ctx->lastEventTime);
 162 }
 163 #endif
 164
 165 struct timespec
 166 evTimeSpec(struct timeval tv) {
 167         struct timespec ts;
 168
 169         ts.tv_sec = tv.tv_sec;
 170         ts.tv_nsec = tv.tv_usec * 1000;
 171         return (ts);
 172 }
 173
 174 struct timeval
 175 evTimeVal(struct timespec ts) {
 176         struct timeval tv;
 177
 178         tv.tv_sec = ts.tv_sec;
 179         tv.tv_usec = ts.tv_nsec / 1000;
 180         return (tv);
 181 }
 182
 183 #ifndef _LIBC
 184 int
 185 evSetTimer(evContext opaqueCtx,
 186            evTimerFunc func,
 187            void *uap,
 188            struct timespec due,
 189            struct timespec inter,
 190            evTimerID *opaqueID
 191 ) {
 192         evContext_p *ctx = opaqueCtx.opaque;
 193         evTimer *id;
 194
 195         evPrintf(ctx, 1,
 196 "evSetTimer(ctx %p, func %p, uap %p, due %ld.%09ld, inter %ld.%09ld)\n",
 197                  ctx, func, uap,
 198                  (long)due.tv_sec, due.tv_nsec,
 199                  (long)inter.tv_sec, inter.tv_nsec);
 200
 201 #ifdef __hpux
 202         /*
 203          * tv_sec and tv_nsec are unsigned.
 204          */
 205         if (due.tv_nsec >= BILLION)
 206                 EV_ERR(EINVAL);
 207
 208         if (inter.tv_nsec >= BILLION)
 209                 EV_ERR(EINVAL);
 210 #else
 211         if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
 212                 EV_ERR(EINVAL);
 213
 214         if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
 215                 EV_ERR(EINVAL);
 216 #endif
 217
 218         /* due={0,0} is a magic cookie meaning "now." */
 219         if (due.tv_sec == (time_t)0 && due.tv_nsec == 0L)
 220                 due = evNowTime();
 221
 222         /* Allocate and fill. */
 223         OKNEW(id);
 224         id->func = func;
 225         id->uap = uap;
 226         id->due = due;
 227         id->inter = inter;
 228
 229         if (heap_insert(ctx->timers, id) < 0)
 230                 return (-1);
 231
 232         /* Remember the ID if the caller provided us a place for it. */
 233         if (opaqueID)
 234                 opaqueID->opaque = id;
 235
 236         if (ctx->debug > 7) {
 237                 evPrintf(ctx, 7, "timers after evSetTimer:\n");
 238                 (void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
 239         }
 240
 241         return (0);
 242 }
 243
 244 int
 245 evClearTimer(evContext opaqueCtx, evTimerID id) {
 246         evContext_p *ctx = opaqueCtx.opaque;
 247         evTimer *del = id.opaque;
 248
 249         if (ctx->cur != NULL &&
 250             ctx->cur->type == Timer &&
 251             ctx->cur->u.timer.this == del) {
 252                 evPrintf(ctx, 8, "deferring delete of timer (executing)\n");
 253                 /*
 254                  * Setting the interval to zero ensures that evDrop() will
 255                  * clean up the timer.
 256                  */
 257                 del->inter = evConsTime(0, 0);
 258                 return (0);
 259         }
 260
 261         if (heap_element(ctx->timers, del->index) != del)
 262                 EV_ERR(ENOENT);
 263
 264         if (heap_delete(ctx->timers, del->index) < 0)
 265                 return (-1);
 266         FREE(del);
 267
 268         if (ctx->debug > 7) {
 269                 evPrintf(ctx, 7, "timers after evClearTimer:\n");
 270                 (void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
 271         }
 272
 273         return (0);
 274 }
 275
 276 int
 277 evConfigTimer(evContext opaqueCtx,
 278              evTimerID id,
 279              const char *param,
 280              int value
 281 ) {
 282         evContext_p *ctx = opaqueCtx.opaque;
 283         evTimer *timer = id.opaque;
 284         int result=0;
 285
 286         UNUSED(value);
 287
 288         if (heap_element(ctx->timers, timer->index) != timer)
 289                 EV_ERR(ENOENT);
 290
 291         if (strcmp(param, "rate") == 0)
 292                 timer->mode |= EV_TMR_RATE;
 293         else if (strcmp(param, "interval") == 0)
 294                 timer->mode &= ~EV_TMR_RATE;
 295         else
 296                 EV_ERR(EINVAL);
 297
 298         return (result);
 299 }
 300
 301 int
 302 evResetTimer(evContext opaqueCtx,
 303              evTimerID id,
 304              evTimerFunc func,
 305              void *uap,
 306              struct timespec due,
 307              struct timespec inter
 308 ) {
 309         evContext_p *ctx = opaqueCtx.opaque;
 310         evTimer *timer = id.opaque;
 311         struct timespec old_due;
 312         int result=0;
 313
 314         if (heap_element(ctx->timers, timer->index) != timer)
 315                 EV_ERR(ENOENT);
 316
 317 #ifdef __hpux
 318         /*
 319          * tv_sec and tv_nsec are unsigned.
 320          */
 321         if (due.tv_nsec >= BILLION)
 322                 EV_ERR(EINVAL);
 323
 324         if (inter.tv_nsec >= BILLION)
 325                 EV_ERR(EINVAL);
 326 #else
 327         if (due.tv_sec < 0 || due.tv_nsec < 0 || due.tv_nsec >= BILLION)
 328                 EV_ERR(EINVAL);
 329
 330         if (inter.tv_sec < 0 || inter.tv_nsec < 0 || inter.tv_nsec >= BILLION)
 331                 EV_ERR(EINVAL);
 332 #endif
 333
 334         old_due = timer->due;
 335
 336         timer->func = func;
 337         timer->uap = uap;
 338         timer->due = due;
 339         timer->inter = inter;
 340
 341         switch (evCmpTime(due, old_due)) {
 342         case -1:
 343                 result = heap_increased(ctx->timers, timer->index);
 344                 break;
 345         case 0:
 346                 result = 0;
 347                 break;
 348         case 1:
 349                 result = heap_decreased(ctx->timers, timer->index);
 350                 break;
 351         }
 352
 353         if (ctx->debug > 7) {
 354                 evPrintf(ctx, 7, "timers after evResetTimer:\n");
 355                 (void) heap_for_each(ctx->timers, print_timer, (void *)ctx);
 356         }
 357
 358         return (result);
 359 }
 360
 361 int
 362 evSetIdleTimer(evContext opaqueCtx,
 363                 evTimerFunc func,
 364                 void *uap,
 365                 struct timespec max_idle,
 366                 evTimerID *opaqueID
 367 ) {
 368         evContext_p *ctx = opaqueCtx.opaque;
 369         idle_timer *tt;
 370
 371         /* Allocate and fill. */
 372         OKNEW(tt);
 373         tt->func = func;
 374         tt->uap = uap;
 375         tt->lastTouched = ctx->lastEventTime;
 376         tt->max_idle = max_idle;
 377
 378         if (evSetTimer(opaqueCtx, idle_timeout, tt,
 379                        evAddTime(ctx->lastEventTime, max_idle),
 380                        max_idle, opaqueID) < 0) {
 381                 FREE(tt);
 382                 return (-1);
 383         }
 384
 385         tt->timer = opaqueID->opaque;
 386
 387         return (0);
 388 }
 389
 390 int
 391 evClearIdleTimer(evContext opaqueCtx, evTimerID id) {
 392         evTimer *del = id.opaque;
 393         idle_timer *tt = del->uap;
 394
 395         FREE(tt);
 396         return (evClearTimer(opaqueCtx, id));
 397 }
 398
 399 int
 400 evResetIdleTimer(evContext opaqueCtx,
 401                  evTimerID opaqueID,
 402                  evTimerFunc func,
 403                  void *uap,
 404                  struct timespec max_idle
 405 ) {
 406         evContext_p *ctx = opaqueCtx.opaque;
 407         evTimer *timer = opaqueID.opaque;
 408         idle_timer *tt = timer->uap;
 409
 410         tt->func = func;
 411         tt->uap = uap;
 412         tt->lastTouched = ctx->lastEventTime;
 413         tt->max_idle = max_idle;
 414
 415         return (evResetTimer(opaqueCtx, opaqueID, idle_timeout, tt,
 416                              evAddTime(ctx->lastEventTime, max_idle),
 417                              max_idle));
 418 }
 419
 420 int
 421 evTouchIdleTimer(evContext opaqueCtx, evTimerID id) {
 422         evContext_p *ctx = opaqueCtx.opaque;
 423         evTimer *t = id.opaque;
 424         idle_timer *tt = t->uap;
 425
 426         tt->lastTouched = ctx->lastEventTime;
 427
 428         return (0);
 429 }
 430
 431 /* Public to the rest of eventlib. */
 432
 433 heap_context
 434 evCreateTimers(const evContext_p *ctx) {
 435
 436         UNUSED(ctx);
 437
 438         return (heap_new(due_sooner, set_index, 2048));
 439 }
 440
 441 void
 442 evDestroyTimers(const evContext_p *ctx) {
 443         (void) heap_for_each(ctx->timers, free_timer, NULL);
 444         (void) heap_free(ctx->timers);
 445 }
 446
 447 /* Private. */
 448
 449 static int
 450 due_sooner(void *a, void *b) {
 451         evTimer *a_timer, *b_timer;
 452
 453         a_timer = a;
 454         b_timer = b;
 455         return (evCmpTime(a_timer->due, b_timer->due) < 0);
 456 }
 457
 458 static void
 459 set_index(void *what, int idx) {
 460         evTimer *timer;
 461
 462         timer = what;
 463         timer->index = idx;
 464 }
 465
 466 static void
 467 free_timer(void *what, void *uap) {
 468         evTimer *t = what;
 469
 470         UNUSED(uap);
 471
 472         FREE(t);
 473 }
 474
 475 static void
 476 print_timer(void *what, void *uap) {
 477         evTimer *cur = what;
 478         evContext_p *ctx = uap;
 479
 480         cur = what;
 481         evPrintf(ctx, 7,
 482             "  func %p, uap %p, due %ld.%09ld, inter %ld.%09ld\n",
 483                  cur->func, cur->uap,
 484                  (long)cur->due.tv_sec, cur->due.tv_nsec,
 485                  (long)cur->inter.tv_sec, cur->inter.tv_nsec);
 486 }
 487
 488 static void
 489 idle_timeout(evContext opaqueCtx,
 490              void *uap,
 491              struct timespec due,
 492              struct timespec inter
 493 ) {
 494         evContext_p *ctx = opaqueCtx.opaque;
 495         idle_timer *this = uap;
 496         struct timespec idle;
 497
 498         UNUSED(due);
 499         UNUSED(inter);
 500
 501         idle = evSubTime(ctx->lastEventTime, this->lastTouched);
 502         if (evCmpTime(idle, this->max_idle) >= 0) {
 503                 (this->func)(opaqueCtx, this->uap, this->timer->due,
 504                              this->max_idle);
 505                 /*
 506                  * Setting the interval to zero will cause the timer to
 507                  * be cleaned up in evDrop().
 508                  */
 509                 this->timer->inter = evConsTime(0L, 0L);
 510                 FREE(this);
 511         } else {
 512                 /* evDrop() will reschedule the timer. */
 513                 this->timer->inter = evSubTime(this->max_idle, idle);
 514         }
 515 }
 516 #endif
 517
 518 /*! \file */