xref: /freebsd/contrib/ntp/ntpd/refclock_jupiter.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*
2  * Copyright (c) 1997, 1998, 2003
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Lawrence Berkeley Laboratory.
17  * 4. The name of the University may not be used to endorse or promote
18  *    products derived from this software without specific prior
19  *    written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 # include <config.h>
36 #endif
37 
38 /* This clock *REQUIRES* the PPS API to be available */
39 #if defined(REFCLOCK) && defined(CLOCK_JUPITER) && defined(HAVE_PPSAPI)
40 
41 #include "ntpd.h"
42 #include "ntp_io.h"
43 #include "ntp_refclock.h"
44 #include "ntp_unixtime.h"
45 #include "ntp_stdlib.h"
46 #include "ntp_calendar.h"
47 #include "ntp_calgps.h"
48 #include "timespecops.h"
49 
50 #include <stdio.h>
51 #include <ctype.h>
52 
53 #include "jupiter.h"
54 #include "ppsapi_timepps.h"
55 
56 #ifdef WORDS_BIGENDIAN
57 #define getshort(s) ((((s) & 0xff) << 8) | (((s) >> 8) & 0xff))
58 #define putshort(s) ((((s) & 0xff) << 8) | (((s) >> 8) & 0xff))
59 #else
60 #define getshort(s) ((u_short)(s))
61 #define putshort(s) ((u_short)(s))
62 #endif
63 
64 /*
65  * This driver supports the Rockwell Jupiter GPS Receiver board
66  * adapted to precision timing applications.  It requires the
67  * ppsclock line discipline or streams module described in the
68  * Line Disciplines and Streams Drivers page. It also requires a
69  * gadget box and 1-PPS level converter, such as described in the
70  * Pulse-per-second (PPS) Signal Interfacing page.
71  *
72  * It may work (with minor modifications) with other Rockwell GPS
73  * receivers such as the CityTracker.
74  */
75 
76 /*
77  * GPS Definitions
78  */
79 #define	DEVICE		"/dev/gps%d"	/* device name and unit */
80 #define	SPEED232	B9600		/* baud */
81 
82 /*
83  * Radio interface parameters
84  */
85 #define	PRECISION	(-18)	/* precision assumed (about 4 us) */
86 #define	REFID	"GPS\0"		/* reference id */
87 #define	DESCRIPTION	"Rockwell Jupiter GPS Receiver" /* who we are */
88 #define	DEFFUDGETIME	0	/* default fudge time (ms) */
89 
90 /* Unix timestamp for the GPS epoch: January 6, 1980 */
91 #define GPS_EPOCH 315964800
92 
93 /* Rata Die Number of first day of GPS epoch. This is the number of days
94  * since 0000-12-31 to 1980-01-06 in the proleptic Gregorian Calendar.
95  */
96 #define RDN_GPS_EPOCH (4*146097 + 138431 + 1)
97 
98 /* Double short to unsigned int */
99 #define DS2UI(p) ((getshort((p)[1]) << 16) | getshort((p)[0]))
100 
101 /* Double short to signed int */
102 #define DS2I(p) ((getshort((p)[1]) << 16) | getshort((p)[0]))
103 
104 /* One week's worth of seconds */
105 #define WEEKSECS (7 * 24 * 60 * 60)
106 
107 /*
108  * Jupiter unit control structure.
109  */
110 struct instance {
111 	struct peer *peer;		/* peer */
112 
113 	pps_params_t pps_params;	/* pps parameters */
114 	pps_info_t pps_info;		/* last pps data */
115 	pps_handle_t pps_handle;	/* pps handle */
116 	u_int	assert;			/* pps edge to use */
117 	u_int	hardpps;		/* enable kernel mode */
118 	l_fp 		rcv_pps;	/* last pps timestamp */
119 	l_fp	        rcv_next;	/* rcv time of next reftime */
120 	TGpsDatum	ref_next;	/* next GPS time stamp to use with PPS */
121 	TGpsDatum	piv_next;	/* pivot for week date unfolding */
122 	uint16_t	piv_hold;	/* TTL for pivot value */
123 	uint16_t	rcvtout;	/* receive timeout ticker */
124 	int wantid;			/* don't reconfig on channel id msg */
125 	u_int  moving;			/* mobile platform? */
126 	u_char sloppyclockflag;		/* fudge flags */
127 	u_short sbuf[512];		/* local input buffer */
128 	int ssize;			/* space used in sbuf */
129 };
130 
131 /*
132  * Function prototypes
133  */
134 static	void	jupiter_canmsg	(struct instance * const, u_int);
135 static	u_short	jupiter_cksum	(u_short *, u_int);
136 static	int	jupiter_config	(struct instance * const);
137 static	void	jupiter_debug	(struct peer *, const char *,
138 				 const char *, ...) NTP_PRINTF(3, 4);
139 static	const char *	jupiter_parse_t	(struct instance * const, u_short *, l_fp);
140 static	const char *	jupiter_parse_gpos(struct instance * const, u_short *);
141 static	void	jupiter_platform(struct instance * const, u_int);
142 static	void	jupiter_poll	(int, struct peer *);
143 static	void	jupiter_control	(int, const struct refclockstat *,
144 				 struct refclockstat *, struct peer *);
145 static	int	jupiter_ppsapi	(struct instance * const);
146 static	int	jupiter_pps	(struct instance * const);
147 static	int	jupiter_recv	(struct instance * const);
148 static	void	jupiter_receive (struct recvbuf * const rbufp);
149 static	void	jupiter_reqmsg	(struct instance * const, u_int, u_int);
150 static	void	jupiter_reqonemsg(struct instance * const, u_int);
151 static	char *	jupiter_send	(struct instance * const, struct jheader *);
152 static	void	jupiter_shutdown(int, struct peer *);
153 static	int	jupiter_start	(int, struct peer *);
154 static	void	jupiter_ticker	(int, struct peer *);
155 
156 /*
157  * Transfer vector
158  */
159 struct	refclock refclock_jupiter = {
160 	jupiter_start,		/* start up driver */
161 	jupiter_shutdown,	/* shut down driver */
162 	jupiter_poll,		/* transmit poll message */
163 	jupiter_control,	/* (clock control) */
164 	noentry,		/* (clock init) */
165 	noentry,		/* (clock buginfo) */
166 	jupiter_ticker		/* 1HZ ticker */
167 };
168 
169 /*
170  * jupiter_start - open the devices and initialize data for processing
171  */
172 static int
173 jupiter_start(
174 	int unit,
175 	struct peer *peer
176 	)
177 {
178 	struct refclockproc * const pp = peer->procptr;
179 	struct instance * up;
180 	int fd;
181 	char gpsdev[20];
182 
183 	/*
184 	 * Open serial port
185 	 */
186 	snprintf(gpsdev, sizeof(gpsdev), DEVICE, unit);
187 	fd = refclock_open(&peer->srcadr, gpsdev, SPEED232, LDISC_RAW);
188 	if (fd <= 0) {
189 		jupiter_debug(peer, "jupiter_start", "open %s: %m",
190 			      gpsdev);
191 		return (0);
192 	}
193 
194 	/* Allocate unit structure */
195 	up = emalloc_zero(sizeof(*up));
196 	up->peer = peer;
197 	pp->io.clock_recv = jupiter_receive;
198 	pp->io.srcclock = peer;
199 	pp->io.datalen = 0;
200 	pp->io.fd = fd;
201 	if (!io_addclock(&pp->io)) {
202 		close(fd);
203 		pp->io.fd = -1;
204 		free(up);
205 		return (0);
206 	}
207 	pp->unitptr = up;
208 
209 	/*
210 	 * Initialize miscellaneous variables
211 	 */
212 	peer->precision = PRECISION;
213 	pp->clockdesc = DESCRIPTION;
214 	memcpy((char *)&pp->refid, REFID, 4);
215 
216 	up->assert = 1;
217 	up->hardpps = 0;
218 	/*
219 	 * Start the PPSAPI interface if it is there. Default to use
220 	 * the assert edge and do not enable the kernel hardpps.
221 	 */
222 	if (time_pps_create(fd, &up->pps_handle) < 0) {
223 		up->pps_handle = 0;
224 		msyslog(LOG_ERR,
225 			"refclock_jupiter: time_pps_create failed: %m");
226 	}
227 	else if (!jupiter_ppsapi(up))
228 		goto clean_up;
229 
230 	/* Ensure the receiver is properly configured */
231 	if (!jupiter_config(up))
232 		goto clean_up;
233 
234 	jupiter_pps(up);	/* get current PPS state */
235 	return (1);
236 
237 clean_up:
238 	jupiter_shutdown(unit, peer);
239 	pp->unitptr = 0;
240 	return (0);
241 }
242 
243 /*
244  * jupiter_shutdown - shut down the clock
245  */
246 static void
247 jupiter_shutdown(int unit, struct peer *peer)
248 {
249 	struct refclockproc * const pp = peer->procptr;
250 	struct instance *     const up = pp->unitptr;
251 
252 	if (!up)
253 		return;
254 
255 	if (up->pps_handle) {
256 		time_pps_destroy(up->pps_handle);
257 		up->pps_handle = 0;
258 	}
259 
260 	if (pp->io.fd != -1)
261 		io_closeclock(&pp->io);
262 	free(up);
263 }
264 
265 /*
266  * jupiter_config - Configure the receiver
267  */
268 static int
269 jupiter_config(struct instance * const up)
270 {
271 	jupiter_debug(up->peer, __func__, "init receiver");
272 
273 	/*
274 	 * Initialize the unit variables
275 	 */
276 	up->sloppyclockflag = up->peer->procptr->sloppyclockflag;
277 	up->moving = !!(up->sloppyclockflag & CLK_FLAG2);
278 	if (up->moving)
279 		jupiter_debug(up->peer, __func__, "mobile platform");
280 
281 	ZERO(up->rcv_next);
282 	ZERO(up->ref_next);
283 	ZERO(up->piv_next);
284 	up->ssize = 0;
285 
286 	/* Stop outputting all messages */
287 	jupiter_canmsg(up, JUPITER_ALL);
288 
289 	/* Request the receiver id so we can syslog the firmware version */
290 	jupiter_reqonemsg(up, JUPITER_O_ID);
291 
292 	/* Flag that this the id was requested (so we don't get called again) */
293 	up->wantid = 1;
294 
295 	/* Request perodic time mark pulse messages */
296 	jupiter_reqmsg(up, JUPITER_O_PULSE, 1);
297 
298 	/* Request perodic geodetic position status */
299 	jupiter_reqmsg(up, JUPITER_O_GPOS, 1);
300 
301 	/* Set application platform type */
302 	if (up->moving)
303 		jupiter_platform(up, JUPITER_I_PLAT_MED);
304 	else
305 		jupiter_platform(up, JUPITER_I_PLAT_LOW);
306 
307 	return (1);
308 }
309 
310 static void
311 jupiter_checkpps(
312 	struct refclockproc * const pp,
313 	struct instance *     const up
314 	)
315 {
316 	l_fp		tstamp, delta;
317 	struct calendar	cd;
318 
319 	if (jupiter_pps(up) || !up->piv_next.weeks)
320 		return;
321 
322 	/* check delay between pulse message and pulse. */
323 	delta = up->rcv_pps;		/* set by jupiter_pps() */
324 	L_SUB(&delta, &up->rcv_next);	/* recv time pulse message */
325 	if (delta.l_ui != 0 || delta.l_uf >= 0xC0000000) {
326 		up->ref_next.weeks = 0;	/* consider as consumed... */
327 		return;
328 	}
329 
330 	pp->lastrec = up->rcv_pps;
331 	tstamp = ntpfp_from_gpsdatum(&up->ref_next);
332 	refclock_process_offset(pp, tstamp, up->rcv_pps, pp->fudgetime1);
333 	up->rcvtout = 2;
334 
335 	gpscal_to_calendar(&cd, &up->ref_next);
336 	refclock_save_lcode(pp, ntpcal_iso8601std(NULL, 0, &cd),
337 			    (size_t)-1);
338 	up->ref_next.weeks = 0;	/* consumed... */
339 }
340 
341 /*
342  * jupiter_ticker - process periodic checks
343  */
344 static void
345 jupiter_ticker(int unit, struct peer *peer)
346 {
347 	struct refclockproc * const pp = peer->procptr;
348 	struct instance *     const up = pp->unitptr;
349 
350 	if (!up)
351 		return;
352 
353 	/* check if we can add another sample now */
354 	jupiter_checkpps(pp, up);
355 
356 	/* check the pivot update cycle */
357 	if (up->piv_hold && !--up->piv_hold)
358 		ZERO(up->piv_next);
359 
360 	if (up->rcvtout)
361 		--up->rcvtout;
362 	else if (pp->coderecv != pp->codeproc)
363 		refclock_samples_expire(pp, 1);
364 }
365 
366 /*
367  * Initialize PPSAPI
368  */
369 int
370 jupiter_ppsapi(
371 	struct instance * const up	/* unit structure pointer */
372 	)
373 {
374 	int capability;
375 
376 	if (time_pps_getcap(up->pps_handle, &capability) < 0) {
377 		msyslog(LOG_ERR,
378 		    "refclock_jupiter: time_pps_getcap failed: %m");
379 		return (0);
380 	}
381 	memset(&up->pps_params, 0, sizeof(pps_params_t));
382 	if (!up->assert)
383 		up->pps_params.mode = capability & PPS_CAPTURECLEAR;
384 	else
385 		up->pps_params.mode = capability & PPS_CAPTUREASSERT;
386 	if (!(up->pps_params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) {
387 		msyslog(LOG_ERR,
388 		    "refclock_jupiter: invalid capture edge %d",
389 		    up->assert);
390 		return (0);
391 	}
392 	up->pps_params.mode |= PPS_TSFMT_TSPEC;
393 	if (time_pps_setparams(up->pps_handle, &up->pps_params) < 0) {
394 		msyslog(LOG_ERR,
395 		    "refclock_jupiter: time_pps_setparams failed: %m");
396 		return (0);
397 	}
398 	if (up->hardpps) {
399 		if (time_pps_kcbind(up->pps_handle, PPS_KC_HARDPPS,
400 				    up->pps_params.mode & ~PPS_TSFMT_TSPEC,
401 				    PPS_TSFMT_TSPEC) < 0) {
402 			msyslog(LOG_ERR,
403 			    "refclock_jupiter: time_pps_kcbind failed: %m");
404 			return (0);
405 		}
406 		hardpps_enable = 1;
407 	}
408 /*	up->peer->precision = PPS_PRECISION; */
409 
410 #if DEBUG
411 	if (debug) {
412 		time_pps_getparams(up->pps_handle, &up->pps_params);
413 		jupiter_debug(up->peer, __func__,
414 			"pps capability 0x%x version %d mode 0x%x kern %d",
415 			capability, up->pps_params.api_version,
416 			up->pps_params.mode, up->hardpps);
417 	}
418 #endif
419 
420 	return (1);
421 }
422 
423 /*
424  * Get PPSAPI timestamps.
425  *
426  * Return 0 on failure and 1 on success.
427  */
428 static int
429 jupiter_pps(struct instance * const up)
430 {
431 	pps_info_t pps_info;
432 	struct timespec timeout, ts;
433 	l_fp tstmp;
434 
435 	/*
436 	 * Convert the timespec nanoseconds field to ntp l_fp units.
437 	 */
438 	if (up->pps_handle == 0)
439 		return 1;
440 	timeout.tv_sec = 0;
441 	timeout.tv_nsec = 0;
442 	memcpy(&pps_info, &up->pps_info, sizeof(pps_info_t));
443 	if (time_pps_fetch(up->pps_handle, PPS_TSFMT_TSPEC, &up->pps_info,
444 	    &timeout) < 0)
445 		return 1;
446 	if (up->pps_params.mode & PPS_CAPTUREASSERT) {
447 		if (pps_info.assert_sequence ==
448 		    up->pps_info.assert_sequence)
449 			return 1;
450 		ts = up->pps_info.assert_timestamp;
451 	} else if (up->pps_params.mode & PPS_CAPTURECLEAR) {
452 		if (pps_info.clear_sequence ==
453 		    up->pps_info.clear_sequence)
454 			return 1;
455 		ts = up->pps_info.clear_timestamp;
456 	} else {
457 		return 1;
458 	}
459 
460 	tstmp = tspec_stamp_to_lfp(ts);
461 	if (L_ISEQU(&tstmp, &up->rcv_pps))
462 		return 1;
463 
464 	up->rcv_pps = tstmp;
465 	return 0;
466 }
467 
468 /*
469  * jupiter_poll - jupiter watchdog routine
470  */
471 static void
472 jupiter_poll(int unit, struct peer *peer)
473 {
474 	struct refclockproc * const pp = peer->procptr;
475 	struct instance *     const up = pp->unitptr;
476 
477 	pp->polls++;
478 
479 	/*
480 	 * If we have new samples since last poll, everything is fine.
481 	 * if not, blarb loudly.
482 	 */
483 	if (pp->coderecv != pp->codeproc) {
484 		refclock_receive(peer);
485 		refclock_report(peer, CEVNT_NOMINAL);
486 	} else {
487 		refclock_report(peer, CEVNT_TIMEOUT);
488 
489 		/* Request the receiver id to trigger a reconfig */
490 		jupiter_reqonemsg(up, JUPITER_O_ID);
491 		up->wantid = 0;
492 	}
493 }
494 
495 /*
496  * jupiter_control - fudge control
497  */
498 static void
499 jupiter_control(
500 	int unit,		/* unit (not used) */
501 	const struct refclockstat *in, /* input parameters (not used) */
502 	struct refclockstat *out, /* output parameters (not used) */
503 	struct peer *peer	/* peer structure pointer */
504 	)
505 {
506 	struct refclockproc * const pp = peer->procptr;
507 	struct instance *     const up = pp->unitptr;
508 
509 	u_char sloppyclockflag;
510 
511 	up->assert = !(pp->sloppyclockflag & CLK_FLAG3);
512 	jupiter_ppsapi(up);
513 
514 	sloppyclockflag = up->sloppyclockflag;
515 	up->sloppyclockflag = pp->sloppyclockflag;
516 	if ((up->sloppyclockflag & CLK_FLAG2) !=
517 	    (sloppyclockflag & CLK_FLAG2)) {
518 		jupiter_debug(peer, __func__,
519 		    "mode switch: reset receiver");
520 		jupiter_config(up);
521 		return;
522 	}
523 }
524 
525 /*
526  * jupiter_receive - receive gps data
527  * Gag me!
528  */
529 static void
530 jupiter_receive(struct recvbuf * const rbufp)
531 {
532 	struct peer *         const peer = rbufp->recv_peer;
533 	struct refclockproc * const pp   = peer->procptr;
534 	struct instance *     const up   = pp->unitptr;
535 
536 	size_t bpcnt;
537 	int cc, size;
538 	const char *cp;
539 	u_char *bp;
540 	u_short *sp;
541 	struct jid *ip;
542 	struct jheader *hp;
543 
544 	/* Initialize pointers and read the timecode and timestamp */
545 	bp = (u_char *)rbufp->recv_buffer;
546 	bpcnt = rbufp->recv_length;
547 
548 	/* This shouldn't happen */
549 	if (bpcnt > sizeof(up->sbuf) - up->ssize)
550 		bpcnt = sizeof(up->sbuf) - up->ssize;
551 
552 	/* Append to input buffer */
553 	memcpy((u_char *)up->sbuf + up->ssize, bp, bpcnt);
554 	up->ssize += bpcnt;
555 
556 	/* While there's at least a header and we parse an intact message */
557 	while (up->ssize > (int)sizeof(*hp) && (cc = jupiter_recv(up)) > 0) {
558 		hp = (struct jheader *)up->sbuf;
559 		sp = (u_short *)(hp + 1);
560 		size = cc - sizeof(*hp);
561 		switch (getshort(hp->id)) {
562 
563 		case JUPITER_O_PULSE:
564 			/* first see if we can push another sample: */
565 			jupiter_checkpps(pp, up);
566 
567 			if (size != sizeof(struct jpulse)) {
568 				jupiter_debug(peer, __func__,
569 				    "pulse: len %d != %u",
570 				    size, (int)sizeof(struct jpulse));
571 				refclock_report(peer, CEVNT_BADREPLY);
572 				break;
573 			}
574 
575 			/* Parse timecode (even when there's no pps)
576 			 *
577 			 * There appears to be a firmware bug related to
578 			 * the pulse message; in addition to the one per
579 			 * second messages, we get an extra pulse
580 			 * message once an hour (on the anniversary of
581 			 * the cold start). It seems to come 200 ms
582 			 * after the one requested.
583 			 *
584 			 * But since we feed samples only when a new PPS
585 			 * pulse is found we can simply ignore that and
586 			 * aggregate/update any existing timing message.
587 			 */
588 			if ((cp = jupiter_parse_t(up, sp, rbufp->recv_time)) != NULL) {
589 				jupiter_debug(peer, __func__,
590 				    "pulse: %s", cp);
591 			}
592 			break;
593 
594 		case JUPITER_O_GPOS:
595 			if (size != sizeof(struct jgpos)) {
596 				jupiter_debug(peer, __func__,
597 				    "gpos: len %d != %u",
598 				    size, (int)sizeof(struct jgpos));
599 				refclock_report(peer, CEVNT_BADREPLY);
600 				break;
601 			}
602 
603 			if ((cp = jupiter_parse_gpos(up, sp)) != NULL) {
604 				jupiter_debug(peer, __func__,
605 				    "gpos: %s", cp);
606 				break;
607 			}
608 			break;
609 
610 		case JUPITER_O_ID:
611 			if (size != sizeof(struct jid)) {
612 				jupiter_debug(peer, __func__,
613 				    "id: len %d != %u",
614 				    size, (int)sizeof(struct jid));
615 				refclock_report(peer, CEVNT_BADREPLY);
616 				break;
617 			}
618 			/*
619 			 * If we got this message because the Jupiter
620 			 * just powered instance, it needs to be reconfigured.
621 			 */
622 			ip = (struct jid *)sp;
623 			jupiter_debug(peer, __func__,
624 			    "%s chan ver %s, %s (%s)",
625 			    ip->chans, ip->vers, ip->date, ip->opts);
626 			msyslog(LOG_DEBUG,
627 			    "jupiter_receive: %s chan ver %s, %s (%s)",
628 			    ip->chans, ip->vers, ip->date, ip->opts);
629 			if (up->wantid)
630 				up->wantid = 0;
631 			else {
632 				jupiter_debug(peer, __func__, "reset receiver");
633 				jupiter_config(up);
634 				/*
635 				 * Restore since jupiter_config() just
636 				 * zeroed it
637 				 */
638 				up->ssize = cc;
639 			}
640 			break;
641 
642 		default:
643 			jupiter_debug(peer, __func__, "unknown message id %d",
644 			    getshort(hp->id));
645 			break;
646 		}
647 		up->ssize -= cc;
648 		if (up->ssize < 0) {
649 			fprintf(stderr, "jupiter_recv: negative ssize!\n");
650 			abort();
651 		} else if (up->ssize > 0)
652 			memcpy(up->sbuf, (u_char *)up->sbuf + cc, up->ssize);
653 	}
654 }
655 
656 static const char *
657 jupiter_parse_t(
658 	struct instance * const up,
659 	u_short *               sp,
660 	l_fp               rcvtime
661 	)
662 {
663 	struct jpulse *jp;
664 	u_int32 sweek;
665 	u_short flags;
666 	l_fp fofs;
667 
668 	jp = (struct jpulse *)sp;
669 	flags = getshort(jp->flags);
670 
671 	/* Toss if not designated "valid" by the gps.
672 	 * !!NOTE!! do *not* kill data received so far!
673 	 */
674 	if ((flags & JUPITER_O_PULSE_VALID) == 0) {
675 		refclock_report(up->peer, CEVNT_BADTIME);
676 		return ("time mark not valid");
677 	}
678 
679 	up->rcv_next = rcvtime; /* remember when this happened */
680 
681 	/* The timecode is presented as seconds into the current GPS week */
682 	sweek = DS2UI(jp->sweek) % WEEKSECS;
683 	/* check if we have to apply the UTC offset ourselves */
684 	if ((flags & JUPITER_O_PULSE_UTC) == 0) {
685 		struct timespec tofs;
686 		tofs.tv_sec  = getshort(jp->offs);
687 		tofs.tv_nsec = DS2I(jp->offns);
688 		fofs = tspec_intv_to_lfp(tofs);
689 		L_NEG(&fofs);
690 	} else {
691 		ZERO(fofs);
692 	}
693 
694 	/*
695 	 * If we don't know the current GPS week, calculate it from the
696 	 * current time. (It's too bad they didn't include this
697 	 * important value in the pulse message).
698 	 *
699 	 * So we pick the pivot value from the other messages like gpos
700 	 * or chan if we can. Of course, the PULSE message can be in UTC
701 	 * or GPS time scale, and the other messages are simply always
702 	 * GPS time.
703 	 *
704 	 * But as long as the difference between the time stamps is less
705 	 * than a half week, the unfolding of a week time is unambigeous
706 	 * and well suited for the problem we have here. And we won't
707 	 * see *that* many leap seconds, ever.
708 	 */
709 	if (up->piv_next.weeks) {
710 		up->ref_next = gpscal_from_weektime2(
711 			sweek, fofs, &up->piv_next);
712 		up->piv_next = up->ref_next;
713 	} else {
714 		up->ref_next = gpscal_from_weektime1(
715 			sweek, fofs, rcvtime);
716 	}
717 
718 
719 
720 	return (NULL);
721 }
722 
723 static const char *
724 jupiter_parse_gpos(
725 	struct instance * const up,
726 	u_short *               sp
727 	)
728 {
729 	struct jgpos *jg;
730 	struct calendar	tref;
731 	char *cp;
732 	struct timespec tofs;
733 	uint16_t	raw_week;
734 	uint32_t	raw_secs;
735 
736 	jg = (struct jgpos *)sp;
737 
738 	if (jg->navval != 0) {
739 		/*
740 		 * Solution not valid. Use caution and refuse
741 		 * to determine GPS week from this message.
742 		 */
743 		return ("Navigation solution not valid");
744 	}
745 
746 	raw_week = getshort(jg->gweek);
747 	raw_secs = DS2UI(jg->sweek);
748 	tofs.tv_sec  = 0;
749 	tofs.tv_nsec = DS2UI(jg->nsweek);
750 	up->piv_next = gpscal_from_gpsweek(raw_week, raw_secs,
751 					   tspec_intv_to_lfp(tofs));
752 	up->piv_hold = 60;
753 
754 	gpscal_to_calendar(&tref, &up->piv_next);
755 	cp = ntpcal_iso8601std(NULL, 0, &tref);
756 	jupiter_debug(up->peer, __func__,
757 		"GPS %s (gweek/sweek %hu/%u)",
758 		      cp, (unsigned short)raw_week, (unsigned int)raw_secs);
759 	return (NULL);
760 }
761 
762 /*
763  * jupiter_debug - print debug messages
764  */
765 static void
766 jupiter_debug(
767 	struct peer *	peer,
768 	const char *	function,
769 	const char *	fmt,
770 	...
771 	)
772 {
773 	char	buffer[200];
774 	va_list	ap;
775 
776 	va_start(ap, fmt);
777 	/*
778 	 * Print debug message to stdout
779 	 * In the future, we may want to get get more creative...
780 	 */
781 	mvsnprintf(buffer, sizeof(buffer), fmt, ap);
782 	record_clock_stats(&peer->srcadr, buffer);
783 #ifdef DEBUG
784 	if (debug) {
785 		printf("%s: %s\n", function, buffer);
786 		fflush(stdout);
787 	}
788 #endif
789 
790 	va_end(ap);
791 }
792 
793 /* Checksum and transmit a message to the Jupiter */
794 static char *
795 jupiter_send(
796 	struct instance * const up,
797 	struct jheader *        hp
798 	)
799 {
800 	u_int len, size;
801 	ssize_t cc;
802 	u_short *sp;
803 	static char errstr[132];
804 
805 	size = sizeof(*hp);
806 	hp->hsum = putshort(jupiter_cksum((u_short *)hp,
807 	    (size / sizeof(u_short)) - 1));
808 	len = getshort(hp->len);
809 	if (len > 0) {
810 		sp = (u_short *)(hp + 1);
811 		sp[len] = putshort(jupiter_cksum(sp, len));
812 		size += (len + 1) * sizeof(u_short);
813 	}
814 
815 	if ((cc = write(up->peer->procptr->io.fd, (char *)hp, size)) < 0) {
816 		msnprintf(errstr, sizeof(errstr), "write: %m");
817 		return (errstr);
818 	} else if (cc != (int)size) {
819 		snprintf(errstr, sizeof(errstr), "short write (%zd != %u)", cc, size);
820 		return (errstr);
821 	}
822 	return (NULL);
823 }
824 
825 /* Request periodic message output */
826 static struct {
827 	struct jheader jheader;
828 	struct jrequest jrequest;
829 } reqmsg = {
830 	{ putshort(JUPITER_SYNC), 0,
831 	    putshort((sizeof(struct jrequest) / sizeof(u_short)) - 1),
832 	    0, JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK |
833 	    JUPITER_FLAG_CONN | JUPITER_FLAG_LOG, 0 },
834 	{ 0, 0, 0, 0 }
835 };
836 
837 /* An interval of zero means to output on trigger */
838 static void
839 jupiter_reqmsg(
840 	struct instance * const up,
841 	u_int                   id,
842 	u_int             interval
843 	)
844 {
845 	struct jheader *hp;
846 	struct jrequest *rp;
847 	char *cp;
848 
849 	hp = &reqmsg.jheader;
850 	hp->id = putshort(id);
851 	rp = &reqmsg.jrequest;
852 	rp->trigger = putshort(interval == 0);
853 	rp->interval = putshort(interval);
854 	if ((cp = jupiter_send(up, hp)) != NULL)
855 		jupiter_debug(up->peer, __func__, "%u: %s", id, cp);
856 }
857 
858 /* Cancel periodic message output */
859 static struct jheader canmsg = {
860 	putshort(JUPITER_SYNC), 0, 0, 0,
861 	JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK | JUPITER_FLAG_DISC,
862 	0
863 };
864 
865 static void
866 jupiter_canmsg(
867 	struct instance * const up,
868 	u_int                   id
869 	)
870 {
871 	struct jheader *hp;
872 	char *cp;
873 
874 	hp = &canmsg;
875 	hp->id = putshort(id);
876 	if ((cp = jupiter_send(up, hp)) != NULL)
877 		jupiter_debug(up->peer, __func__, "%u: %s", id, cp);
878 }
879 
880 /* Request a single message output */
881 static struct jheader reqonemsg = {
882 	putshort(JUPITER_SYNC), 0, 0, 0,
883 	JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK | JUPITER_FLAG_QUERY,
884 	0
885 };
886 
887 static void
888 jupiter_reqonemsg(
889 	struct instance * const up,
890 	u_int                   id
891 	)
892 {
893 	struct jheader *hp;
894 	char *cp;
895 
896 	hp = &reqonemsg;
897 	hp->id = putshort(id);
898 	if ((cp = jupiter_send(up, hp)) != NULL)
899 		jupiter_debug(up->peer, __func__, "%u: %s", id, cp);
900 }
901 
902 /* Set the platform dynamics */
903 static struct {
904 	struct jheader jheader;
905 	struct jplat jplat;
906 } platmsg = {
907 	{ putshort(JUPITER_SYNC), putshort(JUPITER_I_PLAT),
908 	    putshort((sizeof(struct jplat) / sizeof(u_short)) - 1), 0,
909 	    JUPITER_FLAG_REQUEST | JUPITER_FLAG_NAK, 0 },
910 	{ 0, 0, 0 }
911 };
912 
913 static void
914 jupiter_platform(
915 	struct instance * const up,
916 	u_int             platform
917 	)
918 {
919 	struct jheader *hp;
920 	struct jplat *pp;
921 	char *cp;
922 
923 	hp = &platmsg.jheader;
924 	pp = &platmsg.jplat;
925 	pp->platform = putshort(platform);
926 	if ((cp = jupiter_send(up, hp)) != NULL)
927 		jupiter_debug(up->peer, __func__, "%u: %s", platform, cp);
928 }
929 
930 /* Checksum "len" shorts */
931 static u_short
932 jupiter_cksum(u_short *sp, u_int len)
933 {
934 	u_short sum, x;
935 
936 	sum = 0;
937 	while (len-- > 0) {
938 		x = *sp++;
939 		sum += getshort(x);
940 	}
941 	return (~sum + 1);
942 }
943 
944 /* Return the size of the next message (or zero if we don't have it all yet) */
945 static int
946 jupiter_recv(
947 	struct instance * const up
948 	)
949 {
950 	int n, len, size, cc;
951 	struct jheader *hp;
952 	u_char *bp;
953 	u_short *sp;
954 
955 	/* Must have at least a header's worth */
956 	cc = sizeof(*hp);
957 	size = up->ssize;
958 	if (size < cc)
959 		return (0);
960 
961 	/* Search for the sync short if missing */
962 	sp = up->sbuf;
963 	hp = (struct jheader *)sp;
964 	if (getshort(hp->sync) != JUPITER_SYNC) {
965 		/* Wasn't at the front, sync up */
966 		jupiter_debug(up->peer, __func__, "syncing");
967 		bp = (u_char *)sp;
968 		n = size;
969 		while (n >= 2) {
970 			if (bp[0] != (JUPITER_SYNC & 0xff)) {
971 				/*
972 				jupiter_debug(up->peer, __func__,
973 				    "{0x%x}", bp[0]);
974 				*/
975 				++bp;
976 				--n;
977 				continue;
978 			}
979 			if (bp[1] == ((JUPITER_SYNC >> 8) & 0xff))
980 				break;
981 			/*
982 			jupiter_debug(up->peer, __func__,
983 			    "{0x%x 0x%x}", bp[0], bp[1]);
984 			*/
985 			bp += 2;
986 			n -= 2;
987 		}
988 		/*
989 		jupiter_debug(up->peer, __func__, "\n");
990 		*/
991 		/* Shuffle data to front of input buffer */
992 		if (n > 0)
993 			memcpy(sp, bp, n);
994 		size = n;
995 		up->ssize = size;
996 		if (size < cc || hp->sync != JUPITER_SYNC)
997 			return (0);
998 	}
999 
1000 	if (jupiter_cksum(sp, (cc / sizeof(u_short) - 1)) !=
1001 	    getshort(hp->hsum)) {
1002 	    jupiter_debug(up->peer, __func__, "bad header checksum!");
1003 		/* This is drastic but checksum errors should be rare */
1004 		up->ssize = 0;
1005 		return (0);
1006 	}
1007 
1008 	/* Check for a payload */
1009 	len = getshort(hp->len);
1010 	if (len > 0) {
1011 		n = (len + 1) * sizeof(u_short);
1012 		/* Not enough data yet */
1013 		if (size < cc + n)
1014 			return (0);
1015 
1016 		/* Check payload checksum */
1017 		sp = (u_short *)(hp + 1);
1018 		if (jupiter_cksum(sp, len) != getshort(sp[len])) {
1019 			jupiter_debug(up->peer,
1020 			    __func__, "bad payload checksum!");
1021 			/* This is drastic but checksum errors should be rare */
1022 			up->ssize = 0;
1023 			return (0);
1024 		}
1025 		cc += n;
1026 	}
1027 	return (cc);
1028 }
1029 
1030 #else /* not (REFCLOCK && CLOCK_JUPITER && HAVE_PPSAPI) */
1031 int refclock_jupiter_bs;
1032 #endif /* not (REFCLOCK && CLOCK_JUPITER && HAVE_PPSAPI) */
1033