xref: /netbsd-src/external/bsd/ntp/dist/ntpd/refclock_jupiter.c (revision bbde328be4e75ea9ad02e9715ea13ca54b797ada)
1 /*	$NetBSD: refclock_jupiter.c,v 1.1.1.1 2009/12/13 16:55:44 kardel Exp $	*/
2 
3 /*
4  * Copyright (c) 1997, 1998, 2003
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Lawrence Berkeley Laboratory.
19  * 4. The name of the University may not be used to endorse or promote
20  *    products derived from this software without specific prior
21  *    written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifdef HAVE_CONFIG_H
37 # include <config.h>
38 #endif
39 
40 #if defined(REFCLOCK) && defined(CLOCK_JUPITER) && defined(HAVE_PPSAPI)
41 
42 #include "ntpd.h"
43 #include "ntp_io.h"
44 #include "ntp_refclock.h"
45 #include "ntp_unixtime.h"
46 #include "ntp_stdlib.h"
47 
48 #include <stdio.h>
49 #include <ctype.h>
50 
51 #include "jupiter.h"
52 
53 #ifdef HAVE_PPSAPI
54 # include "ppsapi_timepps.h"
55 #endif
56 
57 #ifdef XNTP_BIG_ENDIAN
58 #define getshort(s) ((((s) & 0xff) << 8) | (((s) >> 8) & 0xff))
59 #define putshort(s) ((((s) & 0xff) << 8) | (((s) >> 8) & 0xff))
60 #else
61 #define getshort(s) (s)
62 #define putshort(s) (s)
63 #endif
64 
65 /* XXX */
66 #ifdef sun
67 char *strerror(int);
68 #endif
69 
70 /*
71  * This driver supports the Rockwell Jupiter GPS Receiver board
72  * adapted to precision timing applications.  It requires the
73  * ppsclock line discipline or streams module described in the
74  * Line Disciplines and Streams Drivers page. It also requires a
75  * gadget box and 1-PPS level converter, such as described in the
76  * Pulse-per-second (PPS) Signal Interfacing page.
77  *
78  * It may work (with minor modifications) with other Rockwell GPS
79  * receivers such as the CityTracker.
80  */
81 
82 /*
83  * GPS Definitions
84  */
85 #define	DEVICE		"/dev/gps%d"	/* device name and unit */
86 #define	SPEED232	B9600		/* baud */
87 
88 /*
89  * Radio interface parameters
90  */
91 #define	PRECISION	(-18)	/* precision assumed (about 4 us) */
92 #define	REFID	"GPS\0"		/* reference id */
93 #define	DESCRIPTION	"Rockwell Jupiter GPS Receiver" /* who we are */
94 #define	DEFFUDGETIME	0	/* default fudge time (ms) */
95 
96 /* Unix timestamp for the GPS epoch: January 6, 1980 */
97 #define GPS_EPOCH 315964800
98 
99 /* Double short to unsigned int */
100 #define DS2UI(p) ((getshort((p)[1]) << 16) | getshort((p)[0]))
101 
102 /* Double short to signed int */
103 #define DS2I(p) ((getshort((p)[1]) << 16) | getshort((p)[0]))
104 
105 /* One week's worth of seconds */
106 #define WEEKSECS (7 * 24 * 60 * 60)
107 
108 /*
109  * Jupiter unit control structure.
110  */
111 struct instance {
112 	struct peer *peer;		/* peer */
113 	u_int  pollcnt;			/* poll message counter */
114 	u_int  polled;			/* Hand in a time sample? */
115 #ifdef HAVE_PPSAPI
116 	pps_params_t pps_params;	/* pps parameters */
117 	pps_info_t pps_info;		/* last pps data */
118 	pps_handle_t pps_handle;	/* pps handle */
119 	u_int assert;			/* pps edge to use */
120 	u_int hardpps;			/* enable kernel mode */
121 	struct timespec ts;		/* last timestamp */
122 #endif
123 	l_fp limit;
124 	u_int gpos_gweek;		/* Current GPOS GPS week number */
125 	u_int gpos_sweek;		/* Current GPOS GPS seconds into week */
126 	u_int gweek;			/* current GPS week number */
127 	u_int32 lastsweek;		/* last seconds into GPS week */
128 	time_t timecode;		/* current ntp timecode */
129 	u_int32 stime;			/* used to detect firmware bug */
130 	int wantid;			/* don't reconfig on channel id msg */
131 	u_int  moving;			/* mobile platform? */
132 	u_char sloppyclockflag;		/* fudge flags */
133 	u_short sbuf[512];		/* local input buffer */
134 	int ssize;			/* space used in sbuf */
135 };
136 
137 /*
138  * Function prototypes
139  */
140 static	void	jupiter_canmsg	(struct instance *, u_int);
141 static	u_short	jupiter_cksum	(u_short *, u_int);
142 static	int	jupiter_config	(struct instance *);
143 static	void	jupiter_debug	(struct peer *, char *, char *, ...)
144     __attribute__ ((format (printf, 3, 4)));
145 static	char *	jupiter_parse_t	(struct instance *, u_short *);
146 static	char *	jupiter_parse_gpos	(struct instance *, u_short *);
147 static	void	jupiter_platform	(struct instance *, u_int);
148 static	void	jupiter_poll	(int, struct peer *);
149 static	void	jupiter_control	(int, struct refclockstat *, struct
150 				    refclockstat *, struct peer *);
151 #ifdef HAVE_PPSAPI
152 static	int	jupiter_ppsapi	(struct instance *);
153 static	int	jupiter_pps	(struct instance *);
154 #endif /* HAVE_PPSAPI */
155 static	int	jupiter_recv	(struct instance *);
156 static	void	jupiter_receive (struct recvbuf *rbufp);
157 static	void	jupiter_reqmsg	(struct instance *, u_int, u_int);
158 static	void	jupiter_reqonemsg	(struct instance *, u_int);
159 static	char *	jupiter_send	(struct instance *, struct jheader *);
160 static	void	jupiter_shutdown	(int, struct peer *);
161 static	int	jupiter_start	(int, struct peer *);
162 
163 /*
164  * Transfer vector
165  */
166 struct	refclock refclock_jupiter = {
167 	jupiter_start,		/* start up driver */
168 	jupiter_shutdown,	/* shut down driver */
169 	jupiter_poll,		/* transmit poll message */
170 	jupiter_control,	/* (clock control) */
171 	noentry,		/* (clock init) */
172 	noentry,		/* (clock buginfo) */
173 	NOFLAGS			/* not used */
174 };
175 
176 /*
177  * jupiter_start - open the devices and initialize data for processing
178  */
179 static int
180 jupiter_start(
181 	int unit,
182 	struct peer *peer
183 	)
184 {
185 	struct refclockproc *pp;
186 	struct instance *instance;
187 	int fd = -1;
188 	char gpsdev[20];
189 
190 	/*
191 	 * Open serial port
192 	 */
193 	(void)sprintf(gpsdev, DEVICE, unit);
194 	fd = refclock_open(gpsdev, SPEED232, LDISC_RAW);
195 	if (fd == 0) {
196 		jupiter_debug(peer, "jupiter_start", "open %s: %s",
197 		    gpsdev, strerror(errno));
198 		return (0);
199 	}
200 
201 	/* Allocate unit structure */
202 	if ((instance = (struct instance *)
203 	    emalloc(sizeof(struct instance))) == NULL) {
204 		(void) close(fd);
205 		return (0);
206 	}
207 	memset((char *)instance, 0, sizeof(struct instance));
208 	instance->peer = peer;
209 	pp = peer->procptr;
210 	pp->io.clock_recv = jupiter_receive;
211 	pp->io.srcclock = (caddr_t)peer;
212 	pp->io.datalen = 0;
213 	pp->io.fd = fd;
214 	if (!io_addclock(&pp->io)) {
215 		(void) close(fd);
216 		free(instance);
217 		return (0);
218 	}
219 	pp->unitptr = (caddr_t)instance;
220 
221 	/*
222 	 * Initialize miscellaneous variables
223 	 */
224 	peer->precision = PRECISION;
225 	pp->clockdesc = DESCRIPTION;
226 	memcpy((char *)&pp->refid, REFID, 4);
227 
228 #ifdef HAVE_PPSAPI
229 	instance->assert = 1;
230 	instance->hardpps = 0;
231 	/*
232 	 * Start the PPSAPI interface if it is there. Default to use
233 	 * the assert edge and do not enable the kernel hardpps.
234 	 */
235 	if (time_pps_create(fd, &instance->pps_handle) < 0) {
236 		instance->pps_handle = 0;
237 		msyslog(LOG_ERR,
238 			"refclock_jupiter: time_pps_create failed: %m");
239 	}
240 	else if (!jupiter_ppsapi(instance))
241 		goto clean_up;
242 #endif /* HAVE_PPSAPI */
243 
244 	/* Ensure the receiver is properly configured */
245 	if (!jupiter_config(instance))
246 		goto clean_up;
247 
248 	return (1);
249 
250 clean_up:
251 	jupiter_shutdown(unit, peer);
252 	pp->unitptr = 0;
253 	return (0);
254 }
255 
256 /*
257  * jupiter_shutdown - shut down the clock
258  */
259 static void
260 jupiter_shutdown(int unit, struct peer *peer)
261 {
262 	struct instance *instance;
263 	struct refclockproc *pp;
264 
265 	pp = peer->procptr;
266 	instance = (struct instance *)pp->unitptr;
267 	if (!instance)
268 		return;
269 
270 #ifdef HAVE_PPSAPI
271 	if (instance->pps_handle) {
272 		time_pps_destroy(instance->pps_handle);
273 		instance->pps_handle = 0;
274 	}
275 #endif /* HAVE_PPSAPI */
276 
277 	io_closeclock(&pp->io);
278 	free(instance);
279 }
280 
281 /*
282  * jupiter_config - Configure the receiver
283  */
284 static int
285 jupiter_config(struct instance *instance)
286 {
287 	jupiter_debug(instance->peer, "jupiter_config", "init receiver");
288 
289 	/*
290 	 * Initialize the unit variables
291 	 */
292 	instance->sloppyclockflag = instance->peer->procptr->sloppyclockflag;
293 	instance->moving = !!(instance->sloppyclockflag & CLK_FLAG2);
294 	if (instance->moving)
295 		jupiter_debug(instance->peer, "jupiter_config",
296 			"mobile platform");
297 
298 	instance->pollcnt     = 2;
299 	instance->polled      = 0;
300 	instance->gpos_gweek = 0;
301 	instance->gpos_sweek = 0;
302 	instance->gweek = 0;
303 	instance->lastsweek = 2 * WEEKSECS;
304 	instance->timecode = 0;
305 	instance->stime = 0;
306 	instance->ssize = 0;
307 
308 	/* Stop outputting all messages */
309 	jupiter_canmsg(instance, JUPITER_ALL);
310 
311 	/* Request the receiver id so we can syslog the firmware version */
312 	jupiter_reqonemsg(instance, JUPITER_O_ID);
313 
314 	/* Flag that this the id was requested (so we don't get called again) */
315 	instance->wantid = 1;
316 
317 	/* Request perodic time mark pulse messages */
318 	jupiter_reqmsg(instance, JUPITER_O_PULSE, 1);
319 
320 	/* Request perodic geodetic position status */
321 	jupiter_reqmsg(instance, JUPITER_O_GPOS, 1);
322 
323 	/* Set application platform type */
324 	if (instance->moving)
325 		jupiter_platform(instance, JUPITER_I_PLAT_MED);
326 	else
327 		jupiter_platform(instance, JUPITER_I_PLAT_LOW);
328 
329 	return (1);
330 }
331 
332 #ifdef HAVE_PPSAPI
333 /*
334  * Initialize PPSAPI
335  */
336 int
337 jupiter_ppsapi(
338 	struct instance *instance	/* unit structure pointer */
339 	)
340 {
341 	int capability;
342 
343 	if (time_pps_getcap(instance->pps_handle, &capability) < 0) {
344 		msyslog(LOG_ERR,
345 		    "refclock_jupiter: time_pps_getcap failed: %m");
346 		return (0);
347 	}
348 	memset(&instance->pps_params, 0, sizeof(pps_params_t));
349 	if (!instance->assert)
350 		instance->pps_params.mode = capability & PPS_CAPTURECLEAR;
351 	else
352 		instance->pps_params.mode = capability & PPS_CAPTUREASSERT;
353 	if (!(instance->pps_params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) {
354 		msyslog(LOG_ERR,
355 		    "refclock_jupiter: invalid capture edge %d",
356 		    instance->assert);
357 		return (0);
358 	}
359 	instance->pps_params.mode |= PPS_TSFMT_TSPEC;
360 	if (time_pps_setparams(instance->pps_handle, &instance->pps_params) < 0) {
361 		msyslog(LOG_ERR,
362 		    "refclock_jupiter: time_pps_setparams failed: %m");
363 		return (0);
364 	}
365 	if (instance->hardpps) {
366 		if (time_pps_kcbind(instance->pps_handle, PPS_KC_HARDPPS,
367 				    instance->pps_params.mode & ~PPS_TSFMT_TSPEC,
368 				    PPS_TSFMT_TSPEC) < 0) {
369 			msyslog(LOG_ERR,
370 			    "refclock_jupiter: time_pps_kcbind failed: %m");
371 			return (0);
372 		}
373 		pps_enable = 1;
374 	}
375 /*	instance->peer->precision = PPS_PRECISION; */
376 
377 #if DEBUG
378 	if (debug) {
379 		time_pps_getparams(instance->pps_handle, &instance->pps_params);
380 		jupiter_debug(instance->peer, "refclock_jupiter",
381 			"pps capability 0x%x version %d mode 0x%x kern %d",
382 			capability, instance->pps_params.api_version,
383 			instance->pps_params.mode, instance->hardpps);
384 	}
385 #endif
386 
387 	return (1);
388 }
389 
390 /*
391  * Get PPSAPI timestamps.
392  *
393  * Return 0 on failure and 1 on success.
394  */
395 static int
396 jupiter_pps(struct instance *instance)
397 {
398 	pps_info_t pps_info;
399 	struct timespec timeout, ts;
400 	double dtemp;
401 	l_fp tstmp;
402 
403 	/*
404 	 * Convert the timespec nanoseconds field to ntp l_fp units.
405 	 */
406 	if (instance->pps_handle == 0)
407 		return 1;
408 	timeout.tv_sec = 0;
409 	timeout.tv_nsec = 0;
410 	memcpy(&pps_info, &instance->pps_info, sizeof(pps_info_t));
411 	if (time_pps_fetch(instance->pps_handle, PPS_TSFMT_TSPEC, &instance->pps_info,
412 	    &timeout) < 0)
413 		return 1;
414 	if (instance->pps_params.mode & PPS_CAPTUREASSERT) {
415 		if (pps_info.assert_sequence ==
416 		    instance->pps_info.assert_sequence)
417 			return 1;
418 		ts = instance->pps_info.assert_timestamp;
419 	} else if (instance->pps_params.mode & PPS_CAPTURECLEAR) {
420 		if (pps_info.clear_sequence ==
421 		    instance->pps_info.clear_sequence)
422 			return 1;
423 		ts = instance->pps_info.clear_timestamp;
424 	} else {
425 		return 1;
426 	}
427 	if ((instance->ts.tv_sec == ts.tv_sec) && (instance->ts.tv_nsec == ts.tv_nsec))
428 		return 1;
429 	instance->ts = ts;
430 
431 	tstmp.l_ui = ts.tv_sec + JAN_1970;
432 	dtemp = ts.tv_nsec * FRAC / 1e9;
433 	tstmp.l_uf = (u_int32)dtemp;
434 	instance->peer->procptr->lastrec = tstmp;
435 	return 0;
436 }
437 #endif /* HAVE_PPSAPI */
438 
439 /*
440  * jupiter_poll - jupiter watchdog routine
441  */
442 static void
443 jupiter_poll(int unit, struct peer *peer)
444 {
445 	struct instance *instance;
446 	struct refclockproc *pp;
447 
448 	pp = peer->procptr;
449 	instance = (struct instance *)pp->unitptr;
450 
451 	/*
452 	 * You don't need to poll this clock.  It puts out timecodes
453 	 * once per second.  If asked for a timestamp, take note.
454 	 * The next time a timecode comes in, it will be fed back.
455 	 */
456 
457 	/*
458 	 * If we haven't had a response in a while, reset the receiver.
459 	 */
460 	if (instance->pollcnt > 0) {
461 		instance->pollcnt--;
462 	} else {
463 		refclock_report(peer, CEVNT_TIMEOUT);
464 
465 		/* Request the receiver id to trigger a reconfig */
466 		jupiter_reqonemsg(instance, JUPITER_O_ID);
467 		instance->wantid = 0;
468 	}
469 
470 	/*
471 	 * polled every 64 seconds. Ask jupiter_receive to hand in
472 	 * a timestamp.
473 	 */
474 	instance->polled = 1;
475 	pp->polls++;
476 }
477 
478 /*
479  * jupiter_control - fudge control
480  */
481 static void
482 jupiter_control(
483 	int unit,		/* unit (not used) */
484 	struct refclockstat *in, /* input parameters (not used) */
485 	struct refclockstat *out, /* output parameters (not used) */
486 	struct peer *peer	/* peer structure pointer */
487 	)
488 {
489 	struct refclockproc *pp;
490 	struct instance *instance;
491 	u_char sloppyclockflag;
492 
493 	pp = peer->procptr;
494 	instance = (struct instance *)pp->unitptr;
495 
496 	DTOLFP(pp->fudgetime2, &instance->limit);
497 	/* Force positive value. */
498 	if (L_ISNEG(&instance->limit))
499 		L_NEG(&instance->limit);
500 
501 #ifdef HAVE_PPSAPI
502 	instance->assert = !(pp->sloppyclockflag & CLK_FLAG3);
503 	jupiter_ppsapi(instance);
504 #endif /* HAVE_PPSAPI */
505 
506 	sloppyclockflag = instance->sloppyclockflag;
507 	instance->sloppyclockflag = pp->sloppyclockflag;
508 	if ((instance->sloppyclockflag & CLK_FLAG2) !=
509 	    (sloppyclockflag & CLK_FLAG2)) {
510 		jupiter_debug(peer,
511 		    "jupiter_control",
512 		    "mode switch: reset receiver");
513 		jupiter_config(instance);
514 		return;
515 	}
516 }
517 
518 /*
519  * jupiter_receive - receive gps data
520  * Gag me!
521  */
522 static void
523 jupiter_receive(struct recvbuf *rbufp)
524 {
525 	int bpcnt, cc, size, ppsret;
526 	time_t last_timecode;
527 	u_int32 laststime;
528 	char *cp;
529 	u_char *bp;
530 	u_short *sp;
531 	struct jid *ip;
532 	struct jheader *hp;
533 	struct peer *peer;
534 	struct refclockproc *pp;
535 	struct instance *instance;
536 	l_fp tstamp;
537 
538 	/* Initialize pointers and read the timecode and timestamp */
539 	peer = (struct peer *)rbufp->recv_srcclock;
540 	pp = peer->procptr;
541 	instance = (struct instance *)pp->unitptr;
542 
543 	bp = (u_char *)rbufp->recv_buffer;
544 	bpcnt = rbufp->recv_length;
545 
546 	/* This shouldn't happen */
547 	if (bpcnt > sizeof(instance->sbuf) - instance->ssize)
548 		bpcnt = sizeof(instance->sbuf) - instance->ssize;
549 
550 	/* Append to input buffer */
551 	memcpy((u_char *)instance->sbuf + instance->ssize, bp, bpcnt);
552 	instance->ssize += bpcnt;
553 
554 	/* While there's at least a header and we parse an intact message */
555 	while (instance->ssize > sizeof(*hp) && (cc = jupiter_recv(instance)) > 0) {
556 		instance->pollcnt = 2;
557 
558 		tstamp = rbufp->recv_time;
559 		hp = (struct jheader *)instance->sbuf;
560 		sp = (u_short *)(hp + 1);
561 		size = cc - sizeof(*hp);
562 		switch (getshort(hp->id)) {
563 
564 		case JUPITER_O_PULSE:
565 			if (size != sizeof(struct jpulse)) {
566 				jupiter_debug(peer,
567 				    "jupiter_receive", "pulse: len %d != %u",
568 				    size, (int)sizeof(struct jpulse));
569 				refclock_report(peer, CEVNT_BADREPLY);
570 				break;
571 			}
572 
573 			/*
574 			 * There appears to be a firmware bug related
575 			 * to the pulse message; in addition to the one
576 			 * per second messages, we get an extra pulse
577 			 * message once an hour (on the anniversary of
578 			 * the cold start). It seems to come 200 ms
579 			 * after the one requested. So if we've seen a
580 			 * pulse message in the last 210 ms, we skip
581 			 * this one.
582 			 */
583 			laststime = instance->stime;
584 			instance->stime = DS2UI(((struct jpulse *)sp)->stime);
585 			if (laststime != 0 && instance->stime - laststime <= 21) {
586 				jupiter_debug(peer, "jupiter_receive",
587 				"avoided firmware bug (stime %.2f, laststime %.2f)",
588 				(double)instance->stime * 0.01, (double)laststime * 0.01);
589 				break;
590 			}
591 
592 			/* Retrieve pps timestamp */
593 			ppsret = jupiter_pps(instance);
594 
595 			/*
596 			 * Add one second if msg received early
597 			 * (i.e. before limit, a.k.a. fudgetime2) in
598 			 * the second.
599 			 */
600 			L_SUB(&tstamp, &pp->lastrec);
601 			if (!L_ISGEQ(&tstamp, &instance->limit))
602 				++pp->lastrec.l_ui;
603 
604 			/* Parse timecode (even when there's no pps) */
605 			last_timecode = instance->timecode;
606 			if ((cp = jupiter_parse_t(instance, sp)) != NULL) {
607 				jupiter_debug(peer,
608 				    "jupiter_receive", "pulse: %s", cp);
609 				break;
610 			}
611 
612 			/* Bail if we didn't get a pps timestamp */
613 			if (ppsret)
614 				break;
615 
616 			/* Bail if we don't have the last timecode yet */
617 			if (last_timecode == 0)
618 				break;
619 
620 			/* Add the new sample to a median filter */
621 			tstamp.l_ui = JAN_1970 + last_timecode;
622 			tstamp.l_uf = 0;
623 
624 			refclock_process_offset(pp, tstamp, pp->lastrec, pp->fudgetime1);
625 
626 			/*
627 			 * The clock will blurt a timecode every second
628 			 * but we only want one when polled.  If we
629 			 * havn't been polled, bail out.
630 			 */
631 			if (!instance->polled)
632 				break;
633 			instance->polled = 0;
634 
635 			/*
636 			 * It's a live one!  Remember this time.
637 			 */
638 
639 			pp->lastref = pp->lastrec;
640 			refclock_receive(peer);
641 
642 			/*
643 			 * If we get here - what we got from the clock is
644 			 * OK, so say so
645 			 */
646 			refclock_report(peer, CEVNT_NOMINAL);
647 
648 			/*
649 			 * We have succeeded in answering the poll.
650 			 * Turn off the flag and return
651 			 */
652 			instance->polled = 0;
653 			break;
654 
655 		case JUPITER_O_GPOS:
656 			if (size != sizeof(struct jgpos)) {
657 				jupiter_debug(peer,
658 				    "jupiter_receive", "gpos: len %d != %u",
659 				    size, (int)sizeof(struct jgpos));
660 				refclock_report(peer, CEVNT_BADREPLY);
661 				break;
662 			}
663 
664 			if ((cp = jupiter_parse_gpos(instance, sp)) != NULL) {
665 				jupiter_debug(peer,
666 				    "jupiter_receive", "gpos: %s", cp);
667 				break;
668 			}
669 			break;
670 
671 		case JUPITER_O_ID:
672 			if (size != sizeof(struct jid)) {
673 				jupiter_debug(peer,
674 				    "jupiter_receive", "id: len %d != %u",
675 				    size, (int)sizeof(struct jid));
676 				refclock_report(peer, CEVNT_BADREPLY);
677 				break;
678 			}
679 			/*
680 			 * If we got this message because the Jupiter
681 			 * just powered instance, it needs to be reconfigured.
682 			 */
683 			ip = (struct jid *)sp;
684 			jupiter_debug(peer,
685 			    "jupiter_receive", "%s chan ver %s, %s (%s)",
686 			    ip->chans, ip->vers, ip->date, ip->opts);
687 			msyslog(LOG_DEBUG,
688 			    "jupiter_receive: %s chan ver %s, %s (%s)",
689 			    ip->chans, ip->vers, ip->date, ip->opts);
690 			if (instance->wantid)
691 				instance->wantid = 0;
692 			else {
693 				jupiter_debug(peer,
694 				    "jupiter_receive", "reset receiver");
695 				jupiter_config(instance);
696 				/*
697 				 * Restore since jupiter_config() just
698 				 * zeroed it
699 				 */
700 				instance->ssize = cc;
701 			}
702 			break;
703 
704 		default:
705 			jupiter_debug(peer,
706 			    "jupiter_receive", "unknown message id %d",
707 			    getshort(hp->id));
708 			break;
709 		}
710 		instance->ssize -= cc;
711 		if (instance->ssize < 0) {
712 			fprintf(stderr, "jupiter_recv: negative ssize!\n");
713 			abort();
714 		} else if (instance->ssize > 0)
715 			memcpy(instance->sbuf, (u_char *)instance->sbuf + cc, instance->ssize);
716 	}
717 }
718 
719 static char *
720 jupiter_parse_t(struct instance *instance, u_short *sp)
721 {
722 	struct tm *tm;
723 	char *cp;
724 	struct jpulse *jp;
725 	u_int32 sweek;
726 	time_t last_timecode;
727 	u_short flags;
728 
729 	jp = (struct jpulse *)sp;
730 
731 	/* The timecode is presented as seconds into the current GPS week */
732 	sweek = DS2UI(jp->sweek) % WEEKSECS;
733 
734 	/*
735 	 * If we don't know the current GPS week, calculate it from the
736 	 * current time. (It's too bad they didn't include this
737 	 * important value in the pulse message). We'd like to pick it
738 	 * up from one of the other messages like gpos or chan but they
739 	 * don't appear to be synchronous with time keeping and changes
740 	 * too soon (something like 10 seconds before the new GPS
741 	 * week).
742 	 *
743 	 * If we already know the current GPS week, increment it when
744 	 * we wrap into a new week.
745 	 */
746 	if (instance->gweek == 0) {
747 		if (!instance->gpos_gweek) {
748 			return ("jupiter_parse_t: Unknown gweek");
749 		}
750 
751 		instance->gweek = instance->gpos_gweek;
752 
753 		/*
754 		 * Fix warps. GPOS has GPS time and PULSE has UTC.
755 		 * Plus, GPOS need not be completely in synch with
756 		 * the PPS signal.
757 		 */
758 		if (instance->gpos_sweek >= sweek) {
759 			if ((instance->gpos_sweek - sweek) > WEEKSECS / 2)
760 				++instance->gweek;
761 		}
762 		else {
763 			if ((sweek - instance->gpos_sweek) > WEEKSECS / 2)
764 				--instance->gweek;
765 		}
766 	}
767 	else if (sweek == 0 && instance->lastsweek == WEEKSECS - 1) {
768 		++instance->gweek;
769 		jupiter_debug(instance->peer,
770 		    "jupiter_parse_t", "NEW gps week %u", instance->gweek);
771 	}
772 
773 	/*
774 	 * See if the sweek stayed the same (this happens when there is
775 	 * no pps pulse).
776 	 *
777 	 * Otherwise, look for time warps:
778 	 *
779 	 *   - we have stored at least one lastsweek and
780 	 *   - the sweek didn't increase by one and
781 	 *   - we didn't wrap to a new GPS week
782 	 *
783 	 * Then we warped.
784 	 */
785 	if (instance->lastsweek == sweek)
786 		jupiter_debug(instance->peer,
787 		    "jupiter_parse_t", "gps sweek not incrementing (%d)",
788 		    sweek);
789 	else if (instance->lastsweek != 2 * WEEKSECS &&
790 	    instance->lastsweek + 1 != sweek &&
791 	    !(sweek == 0 && instance->lastsweek == WEEKSECS - 1))
792 		jupiter_debug(instance->peer,
793 		    "jupiter_parse_t", "gps sweek jumped (was %d, now %d)",
794 		    instance->lastsweek, sweek);
795 	instance->lastsweek = sweek;
796 
797 	/* This timecode describes next pulse */
798 	last_timecode = instance->timecode;
799 	instance->timecode =
800 	    GPS_EPOCH + (instance->gweek * WEEKSECS) + sweek;
801 
802 	if (last_timecode == 0)
803 		/* XXX debugging */
804 		jupiter_debug(instance->peer,
805 		    "jupiter_parse_t", "UTC <none> (gweek/sweek %u/%u)",
806 		    instance->gweek, sweek);
807 	else {
808 		/* XXX debugging */
809 		tm = gmtime(&last_timecode);
810 		cp = asctime(tm);
811 
812 		jupiter_debug(instance->peer,
813 		    "jupiter_parse_t", "UTC %.24s (gweek/sweek %u/%u)",
814 		    cp, instance->gweek, sweek);
815 
816 		/* Billboard last_timecode (which is now the current time) */
817 		instance->peer->procptr->year   = tm->tm_year + 1900;
818 		instance->peer->procptr->day    = tm->tm_yday + 1;
819 		instance->peer->procptr->hour   = tm->tm_hour;
820 		instance->peer->procptr->minute = tm->tm_min;
821 		instance->peer->procptr->second = tm->tm_sec;
822 	}
823 
824 	flags = getshort(jp->flags);
825 
826 	/* Toss if not designated "valid" by the gps */
827 	if ((flags & JUPITER_O_PULSE_VALID) == 0) {
828 		refclock_report(instance->peer, CEVNT_BADTIME);
829 		return ("time mark not valid");
830 	}
831 
832 	/* We better be sync'ed to UTC... */
833 	if ((flags & JUPITER_O_PULSE_UTC) == 0) {
834 		refclock_report(instance->peer, CEVNT_BADTIME);
835 		return ("time mark not sync'ed to UTC");
836 	}
837 
838 	return (NULL);
839 }
840 
841 static char *
842 jupiter_parse_gpos(struct instance *instance, u_short *sp)
843 {
844 	struct jgpos *jg;
845 	time_t t;
846 	struct tm *tm;
847 	char *cp;
848 
849 	jg = (struct jgpos *)sp;
850 
851 	if (jg->navval != 0) {
852 		/*
853 		 * Solution not valid. Use caution and refuse
854 		 * to determine GPS week from this message.
855 		 */
856 		instance->gpos_gweek = 0;
857 		instance->gpos_sweek = 0;
858 		return ("Navigation solution not valid");
859 	}
860 
861 	instance->gpos_gweek = jg->gweek;
862 	instance->gpos_sweek = DS2UI(jg->sweek);
863 	while(instance->gpos_sweek >= WEEKSECS) {
864 		instance->gpos_sweek -= WEEKSECS;
865 		++instance->gpos_gweek;
866 	}
867 	instance->gweek = 0;
868 
869 	t = GPS_EPOCH + (instance->gpos_gweek * WEEKSECS) + instance->gpos_sweek;
870 	tm = gmtime(&t);
871 	cp = asctime(tm);
872 
873 	jupiter_debug(instance->peer,
874 		"jupiter_parse_g", "GPS %.24s (gweek/sweek %u/%u)",
875 		cp, instance->gpos_gweek, instance->gpos_sweek);
876 	return (NULL);
877 }
878 
879 /*
880  * jupiter_debug - print debug messages
881  */
882 #if defined(__STDC__) || defined(SYS_WINNT)
883 static void
884 jupiter_debug(struct peer *peer, char *function, char *fmt, ...)
885 #else
886 static void
887 jupiter_debug(peer, function, fmt, va_alist)
888 	struct peer *peer;
889 	char *function;
890 	char *fmt;
891 #endif /* __STDC__ */
892 {
893 	char buffer[200];
894 	va_list ap;
895 
896 #if defined(__STDC__) || defined(SYS_WINNT)
897 	va_start(ap, fmt);
898 #else
899 	va_start(ap);
900 #endif /* __STDC__ */
901 	/*
902 	 * Print debug message to stdout
903 	 * In the future, we may want to get get more creative...
904 	 */
905 	vsnprintf(buffer, sizeof(buffer), fmt, ap);
906 	record_clock_stats(&(peer->srcadr), buffer);
907 #ifdef DEBUG
908 	if (debug) {
909 		fprintf(stdout, "%s: ", function);
910 		fprintf(stdout, buffer);
911 		fprintf(stdout, "\n");
912 		fflush(stdout);
913 	}
914 #endif
915 
916 	va_end(ap);
917 }
918 
919 /* Checksum and transmit a message to the Jupiter */
920 static char *
921 jupiter_send(struct instance *instance, struct jheader *hp)
922 {
923 	u_int len, size;
924 	int cc;
925 	u_short *sp;
926 	static char errstr[132];
927 
928 	size = sizeof(*hp);
929 	hp->hsum = putshort(jupiter_cksum((u_short *)hp,
930 	    (size / sizeof(u_short)) - 1));
931 	len = getshort(hp->len);
932 	if (len > 0) {
933 		sp = (u_short *)(hp + 1);
934 		sp[len] = putshort(jupiter_cksum(sp, len));
935 		size += (len + 1) * sizeof(u_short);
936 	}
937 
938 	if ((cc = write(instance->peer->procptr->io.fd, (char *)hp, size)) < 0) {
939 		(void)sprintf(errstr, "write: %s", strerror(errno));
940 		return (errstr);
941 	} else if (cc != size) {
942 		(void)sprintf(errstr, "short write (%d != %d)", cc, size);
943 		return (errstr);
944 	}
945 	return (NULL);
946 }
947 
948 /* Request periodic message output */
949 static struct {
950 	struct jheader jheader;
951 	struct jrequest jrequest;
952 } reqmsg = {
953 	{ putshort(JUPITER_SYNC), 0,
954 	    putshort((sizeof(struct jrequest) / sizeof(u_short)) - 1),
955 	    0, JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK |
956 	    JUPITER_FLAG_CONN | JUPITER_FLAG_LOG, 0 },
957 	{ 0, 0, 0, 0 }
958 };
959 
960 /* An interval of zero means to output on trigger */
961 static void
962 jupiter_reqmsg(struct instance *instance, u_int id,
963     u_int interval)
964 {
965 	struct jheader *hp;
966 	struct jrequest *rp;
967 	char *cp;
968 
969 	hp = &reqmsg.jheader;
970 	hp->id = putshort(id);
971 	rp = &reqmsg.jrequest;
972 	rp->trigger = putshort(interval == 0);
973 	rp->interval = putshort(interval);
974 	if ((cp = jupiter_send(instance, hp)) != NULL)
975 		jupiter_debug(instance->peer, "jupiter_reqmsg", "%u: %s", id, cp);
976 }
977 
978 /* Cancel periodic message output */
979 static struct jheader canmsg = {
980 	putshort(JUPITER_SYNC), 0, 0, 0,
981 	JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK | JUPITER_FLAG_DISC,
982 	0
983 };
984 
985 static void
986 jupiter_canmsg(struct instance *instance, u_int id)
987 {
988 	struct jheader *hp;
989 	char *cp;
990 
991 	hp = &canmsg;
992 	hp->id = putshort(id);
993 	if ((cp = jupiter_send(instance, hp)) != NULL)
994 		jupiter_debug(instance->peer, "jupiter_canmsg", "%u: %s", id, cp);
995 }
996 
997 /* Request a single message output */
998 static struct jheader reqonemsg = {
999 	putshort(JUPITER_SYNC), 0, 0, 0,
1000 	JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK | JUPITER_FLAG_QUERY,
1001 	0
1002 };
1003 
1004 static void
1005 jupiter_reqonemsg(struct instance *instance, u_int id)
1006 {
1007 	struct jheader *hp;
1008 	char *cp;
1009 
1010 	hp = &reqonemsg;
1011 	hp->id = putshort(id);
1012 	if ((cp = jupiter_send(instance, hp)) != NULL)
1013 		jupiter_debug(instance->peer, "jupiter_reqonemsg", "%u: %s", id, cp);
1014 }
1015 
1016 /* Set the platform dynamics */
1017 static struct {
1018 	struct jheader jheader;
1019 	struct jplat jplat;
1020 } platmsg = {
1021 	{ putshort(JUPITER_SYNC), putshort(JUPITER_I_PLAT),
1022 	    putshort((sizeof(struct jplat) / sizeof(u_short)) - 1), 0,
1023 	    JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK, 0 },
1024 	{ 0, 0, 0 }
1025 };
1026 
1027 static void
1028 jupiter_platform(struct instance *instance, u_int platform)
1029 {
1030 	struct jheader *hp;
1031 	struct jplat *pp;
1032 	char *cp;
1033 
1034 	hp = &platmsg.jheader;
1035 	pp = &platmsg.jplat;
1036 	pp->platform = putshort(platform);
1037 	if ((cp = jupiter_send(instance, hp)) != NULL)
1038 		jupiter_debug(instance->peer, "jupiter_platform", "%u: %s", platform, cp);
1039 }
1040 
1041 /* Checksum "len" shorts */
1042 static u_short
1043 jupiter_cksum(u_short *sp, u_int len)
1044 {
1045 	u_short sum, x;
1046 
1047 	sum = 0;
1048 	while (len-- > 0) {
1049 		x = *sp++;
1050 		sum += getshort(x);
1051 	}
1052 	return (~sum + 1);
1053 }
1054 
1055 /* Return the size of the next message (or zero if we don't have it all yet) */
1056 static int
1057 jupiter_recv(struct instance *instance)
1058 {
1059 	int n, len, size, cc;
1060 	struct jheader *hp;
1061 	u_char *bp;
1062 	u_short *sp;
1063 
1064 	/* Must have at least a header's worth */
1065 	cc = sizeof(*hp);
1066 	size = instance->ssize;
1067 	if (size < cc)
1068 		return (0);
1069 
1070 	/* Search for the sync short if missing */
1071 	sp = instance->sbuf;
1072 	hp = (struct jheader *)sp;
1073 	if (getshort(hp->sync) != JUPITER_SYNC) {
1074 		/* Wasn't at the front, sync up */
1075 		jupiter_debug(instance->peer, "jupiter_recv", "syncing");
1076 		bp = (u_char *)sp;
1077 		n = size;
1078 		while (n >= 2) {
1079 			if (bp[0] != (JUPITER_SYNC & 0xff)) {
1080 				/*
1081 				jupiter_debug(instance->peer, "{0x%x}", bp[0]);
1082 				*/
1083 				++bp;
1084 				--n;
1085 				continue;
1086 			}
1087 			if (bp[1] == ((JUPITER_SYNC >> 8) & 0xff))
1088 				break;
1089 			/*
1090 			jupiter_debug(instance->peer, "{0x%x 0x%x}", bp[0], bp[1]);
1091 			*/
1092 			bp += 2;
1093 			n -= 2;
1094 		}
1095 		/*
1096 		jupiter_debug(instance->peer, "\n");
1097 		*/
1098 		/* Shuffle data to front of input buffer */
1099 		if (n > 0)
1100 			memcpy(sp, bp, n);
1101 		size = n;
1102 		instance->ssize = size;
1103 		if (size < cc || hp->sync != JUPITER_SYNC)
1104 			return (0);
1105 	}
1106 
1107 	if (jupiter_cksum(sp, (cc / sizeof(u_short) - 1)) !=
1108 	    getshort(hp->hsum)) {
1109 	    jupiter_debug(instance->peer, "jupiter_recv", "bad header checksum!");
1110 		/* This is drastic but checksum errors should be rare */
1111 		instance->ssize = 0;
1112 		return (0);
1113 	}
1114 
1115 	/* Check for a payload */
1116 	len = getshort(hp->len);
1117 	if (len > 0) {
1118 		n = (len + 1) * sizeof(u_short);
1119 		/* Not enough data yet */
1120 		if (size < cc + n)
1121 			return (0);
1122 
1123 		/* Check payload checksum */
1124 		sp = (u_short *)(hp + 1);
1125 		if (jupiter_cksum(sp, len) != getshort(sp[len])) {
1126 			jupiter_debug(instance->peer,
1127 			    "jupiter_recv", "bad payload checksum!");
1128 			/* This is drastic but checksum errors should be rare */
1129 			instance->ssize = 0;
1130 			return (0);
1131 		}
1132 		cc += n;
1133 	}
1134 	return (cc);
1135 }
1136 
1137 #else /* not (REFCLOCK && CLOCK_JUPITER && HAVE_PPSAPI) */
1138 int refclock_jupiter_bs;
1139 #endif /* not (REFCLOCK && CLOCK_JUPITER && HAVE_PPSAPI) */
1140