src/kits/network/netresolv/isc/ev_timers.c

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