2  * refclock_shm - clock driver for utc via shared memory
3  * - under construction -
4  * To add new modes: Extend or union the shmTime-struct. Do not
6  * will specify wrong size of shared memory-segment
52 #define PRECISION       (-1)    /* precision assumed (0.5 s) */
78 	shm_start,              /* start up driver */
88 	int    mode; /* 0 - if valid is set:
91 		      * 1 - if valid is set:
111 	struct shmTime *shm;	/* pointer to shared memory segment */
114 	/* debugging/monitoring counters - reset when printed */
115 	int ticks;		/* number of attempts to read data*/
139 	 * Big units will give non-ascii but that's OK  in getShmTime()
144 	if (shmid == -1) { /* error */  in getShmTime()
149 	if (p == (struct shmTime *)-1) { /* error */  in getShmTime()
213  * shm_start - attach to shared memory
221 	struct refclockproc * const pp = peer->procptr;  in shm_start()
222 	struct shmunit *      const up = emalloc_zero(sizeof(*up));  in shm_start()  local
224 	pp->io.clock_recv = noentry;  in shm_start()
225 	pp->io.srcclock = peer;  in shm_start()
226 	pp->io.datalen = 0;  in shm_start()
227 	pp->io.fd = -1;  in shm_start()
229 	up->forall = (unit >= 2) && !(peer->ttl & SHM_MODE_PRIVATE);  in shm_start()
231 	up->shm = getShmTime(unit, up->forall);  in shm_start()
236 	memcpy((char *)&pp->refid, REFID, 4);  in shm_start()
237 	if (up->shm != 0) {  in shm_start()
238 		pp->unitptr = up;  in shm_start()
239 		up->shm->precision = PRECISION;  in shm_start()
240 		peer->precision = up->shm->precision;  in shm_start()
241 		up->shm->valid = 0;  in shm_start()
242 		up->shm->nsamples = NSAMPLES;  in shm_start()
243 		pp->clockdesc = DESCRIPTION;  in shm_start()
244 		/* items to be changed later in 'shm_control()': */  in shm_start()
245 		up->max_delay = 5;  in shm_start()
246 		up->max_delta = 4*3600;  in shm_start()
249 		free(up);  in shm_start()
250 		pp->unitptr = NULL;  in shm_start()
257  * shm_control - configure flag1/time2 params
259  * These are not yet available during 'shm_start', so we have to do any
260  * pre-computations we want to avoid during regular poll/timer callbacks
271 	struct refclockproc * const pp = peer->procptr;  in shm_control()
272 	struct shmunit *      const up = pp->unitptr;  in shm_control()  local
277 	if (NULL == up)  in shm_control()
279 	if (pp->sloppyclockflag & CLK_FLAG1)  in shm_control()
280 		up->max_delta = 0;  in shm_control()
281 	else if (pp->fudgetime2 < 1. || pp->fudgetime2 > 86400.)  in shm_control()
282 		up->max_delta = 4*3600;  in shm_control()
284 		up->max_delta = (time_t)floor(pp->fudgetime2 + 0.5);  in shm_control()
289  * shm_shutdown - shut down the clock
297 	struct refclockproc * const pp = peer->procptr;  in shm_shutdown()
298 	struct shmunit *      const up = pp->unitptr;  in shm_shutdown()  local
301 	if (NULL == up)  in shm_shutdown()
306 	(void)shmdt((char *)up->shm);  in shm_shutdown()
310 	UnmapViewOfFile(up->shm);  in shm_shutdown()
313 	free(up);  in shm_shutdown()
318  * shm_poll - called by the transmit procedure
326 	struct refclockproc * const pp = peer->procptr;  in shm_poll()
327 	struct shmunit *      const up = pp->unitptr;  in shm_poll()  local
330 	pp->polls++;  in shm_poll()
333 	major_error = max(up->notready, up->bad);  in shm_poll()
334 	major_error = max(major_error, up->clash);  in shm_poll()
340         if (pp->coderecv != pp->codeproc) {  in shm_poll()
342 		pp->lastref = pp->lastrec;  in shm_poll()
345 	} else if (NULL == up->shm) { /* is this possible at all? */  in shm_poll()
348 	} else if (major_error == up->clash) {  in shm_poll()
351 	} else if (major_error == up->bad) {  in shm_poll()
383 /* try to grab a sample from the specified SHM segment */  in shm_query()
396 	shm_stat->status = NO_SEGMENT;  in shm_query()
400     /*@-type@*//* splint is confused about struct timespec */  in shm_query()
401     shm_stat->tvc.tv_sec = shm_stat->tvc.tv_nsec = 0;  in shm_query()
406 	shm_stat->tvc.tv_sec = now;  in shm_query()
409     /* relying on word access to be atomic here */  in shm_query()
410     if (shm->valid == 0) {  in shm_query()
411 	shm_stat->status = NOT_READY;  in shm_query()
415     cnt = shm->count;  in shm_query()
420      * (b) memset compiles to an uninterruptible single-instruction bitblt.  in shm_query()
424     shm->valid = 0;  in shm_query()
429      * Not supported in mode 0, and word access to the count field   in shm_query()
430      * must be atomic for this to work.  in shm_query()
432     if (shmcopy.mode > 0 && cnt != shm->count) {  in shm_query()
433 	shm_stat->status = CLASH;  in shm_query()
434 	return shm_stat->status;  in shm_query()
437     shm_stat->status = OK;  in shm_query()
438     shm_stat->mode = shmcopy.mode;  in shm_query()
442 	shm_stat->tvr.tv_sec	= shmcopy.receiveTimeStampSec;  in shm_query()
443 	shm_stat->tvr.tv_nsec	= shmcopy.receiveTimeStampUSec * 1000;  in shm_query()
445 	shm_stat->tvt.tv_sec	= shmcopy.clockTimeStampSec;  in shm_query()
446 	shm_stat->tvt.tv_nsec	= shmcopy.clockTimeStampUSec * 1000;  in shm_query()
456 	** *rounded* usecs, and the logic to deal with  in shm_query()
457 	** wrap-arounds in the presence of rounded values is  in shm_query()
460 	if (   ((cns_new - (unsigned)shm_stat->tvt.tv_nsec) < 1000)  in shm_query()
461 	       && ((rns_new - (unsigned)shm_stat->tvr.tv_nsec) < 1000)) {  in shm_query()
462 	    shm_stat->tvt.tv_nsec = cns_new;  in shm_query()
463 	    shm_stat->tvr.tv_nsec = rns_new;  in shm_query()
465 	/* At this point shm_stat->tvr and shm_stat->tvt contain valid ns-level  in shm_query()
467 	** us-level timestamps  in shm_query()
473 	shm_stat->tvr.tv_sec	= shmcopy.receiveTimeStampSec;  in shm_query()
474 	shm_stat->tvr.tv_nsec	= shmcopy.receiveTimeStampUSec * 1000;  in shm_query()
476 	shm_stat->tvt.tv_sec	= shmcopy.clockTimeStampSec;  in shm_query()
477 	shm_stat->tvt.tv_nsec	= shmcopy.clockTimeStampUSec * 1000;  in shm_query()
483 	if (   ((cns_new - (unsigned)shm_stat->tvt.tv_nsec) < 1000)  in shm_query()
484 	       && ((rns_new - (unsigned)shm_stat->tvr.tv_nsec) < 1000)) {  in shm_query()
485 	    shm_stat->tvt.tv_nsec = cns_new;  in shm_query()
486 	    shm_stat->tvr.tv_nsec = rns_new;  in shm_query()
488 	/* At this point shm_stat->tvr and shm_stat->tvt contains valid ns-level  in shm_query()
490 	** us-level timestamps  in shm_query()
495 	shm_stat->status = BAD_MODE;  in shm_query()
498     /*@-type@*/  in shm_query()
505     shm_stat->leap = shmcopy.leap;  in shm_query()
506     shm_stat->precision = shmcopy.precision;  in shm_query()
508     return shm_stat->status;  in shm_query()
512  * shm_timer - called once every second.
514  * This tries to grab a sample from the SHM segment, filtering bad ones
522 	struct refclockproc * const pp = peer->procptr;  in shm_timer()
523 	struct shmunit *      const up = pp->unitptr;  in shm_timer()  local
539 	up->ticks++;  in shm_timer()
540 	if ((shm = up->shm) == NULL) {  in shm_timer()
541 		/* try to map again - this may succeed if meanwhile some-  in shm_timer()
543 		shm = up->shm = getShmTime(unit, up->forall);  in shm_timer()
546 				    refnumtoa(&peer->srcadr)));  in shm_timer()
557 			refnumtoa(&peer->srcadr), shm_stat.mode));  in shm_timer()
563 	    DPRINTF(1, ("%s: SHM not ready\n",refnumtoa(&peer->srcadr)));  in shm_timer()
564 	    up->notready++;  in shm_timer()
568 			refnumtoa(&peer->srcadr), shm->mode));  in shm_timer()
569 	    up->bad++;  in shm_timer()
571 		     shm->mode);  in shm_timer()
575 			refnumtoa(&peer->srcadr)));  in shm_timer()
577 	    up->clash++;  in shm_timer()
581 			refnumtoa(&peer->srcadr)));  in shm_timer()
583 	    up->bad++;  in shm_timer()
588 	/* format the last time code in human-readable form into  in shm_timer()
589 	 * 'pp->a_lastcode'. Someone claimed: "NetBSD has incompatible  in shm_timer()
598 	/* add ntpq -c cv timecode in ISO 8601 format */  in shm_timer()
599 	c = snprintf(pp->a_lastcode, sizeof(pp->a_lastcode),  in shm_timer()
600 		     "%04u-%02u-%02uT%02u:%02u:%02u.%09ldZ",  in shm_timer()
604 	pp->lencode = (c > 0 && (size_t)c < sizeof(pp->a_lastcode)) ? c : 0;  in shm_timer()
607 	tt = shm_stat.tvc.tv_sec - shm_stat.tvr.tv_sec;  in shm_timer()
608 	if (tt < 0 || tt > up->max_delay) {  in shm_timer()
610 			    refnumtoa(&peer->srcadr), (long long)tt));  in shm_timer()
611 		up->bad++;  in shm_timer()
618 	tt = shm_stat.tvr.tv_sec - shm_stat.tvt.tv_sec - (shm_stat.tvr.tv_nsec < shm_stat.tvt.tv_nsec);  in shm_timer()
620 		tt = -tt;  in shm_timer()
621 	if (up->max_delta > 0 && tt > up->max_delta) {  in shm_timer()
623 			    refnumtoa(&peer->srcadr), (long long)tt));  in shm_timer()
624 		up->bad++;  in shm_timer()
630 	/* if we really made it to this point... we're winners! */  in shm_timer()
632 		    refnumtoa(&peer->srcadr)));  in shm_timer()
635 	pp->leap = shm_stat.leap;  in shm_timer()
636 	peer->precision = shm_stat.precision;  in shm_timer()
637 	refclock_process_offset(pp, tsref, tsrcv, pp->fudgetime1);  in shm_timer()
638 	up->good++;  in shm_timer()
642  * shm_clockstats - dump and reset counters
649 	struct refclockproc * const pp = peer->procptr;  in shm_clockstats()
650 	struct shmunit *      const up = pp->unitptr;  in shm_clockstats()  local
653 	if (pp->sloppyclockflag & CLK_FLAG4) {  in shm_clockstats()
655 			&peer->srcadr, "%3d %3d %3d %3d %3d",  in shm_clockstats()
656 			up->ticks, up->good, up->notready,  in shm_clockstats()
657 			up->bad, up->clash);  in shm_clockstats()
659 	up->ticks = up->good = up->notready = up->bad = up->clash = 0;  in shm_clockstats()