1/*	$NetBSD: refclock_pcf.c,v 1.9 2020/05/25 20:47:26 christos Exp $	*/
2
3/*
4 * refclock_pcf - clock driver for the Conrad parallel port radio clock
5 */
6
7#ifdef HAVE_CONFIG_H
8# include <config.h>
9#endif
10
11#if defined(REFCLOCK) && defined(CLOCK_PCF)
12
13#include "ntpd.h"
14#include "ntp_io.h"
15#include "ntp_refclock.h"
16#include "ntp_calendar.h"
17#include "ntp_stdlib.h"
18
19/*
20 * This driver supports the parallel port radio clock sold by Conrad
21 * Electronic under order numbers 967602 and 642002.
22 *
23 * It requires that the local timezone be CET/CEST and that the pcfclock
24 * device driver be installed.  A device driver for Linux is available at
25 * http://home.pages.de/~voegele/pcf.html.  Information about a FreeBSD
26 * driver is available at http://schumann.cx/pcfclock/.
27 */
28
29/*
30 * Interface definitions
31 */
32#define	DEVICE		"/dev/pcfclocks/%d"
33#define	OLDDEVICE	"/dev/pcfclock%d"
34#define	PRECISION	(-1)	/* precision assumed (about 0.5 s) */
35#define REFID		"PCF"
36#define DESCRIPTION	"Conrad parallel port radio clock"
37
38#define LENPCF		18	/* timecode length */
39
40/*
41 * Function prototypes
42 */
43static	int 	pcf_start 		(int, struct peer *);
44static	void	pcf_shutdown		(int, struct peer *);
45static	void	pcf_poll		(int, struct peer *);
46
47/*
48 * Transfer vector
49 */
50struct  refclock refclock_pcf = {
51	pcf_start,              /* start up driver */
52	pcf_shutdown,           /* shut down driver */
53	pcf_poll,               /* transmit poll message */
54	noentry,                /* not used */
55	noentry,                /* initialize driver (not used) */
56	noentry,                /* not used */
57	NOFLAGS                 /* not used */
58};
59
60
61/*
62 * pcf_start - open the device and initialize data for processing
63 */
64static int
65pcf_start(
66     	int unit,
67	struct peer *peer
68	)
69{
70	struct refclockproc *pp;
71	int fd;
72	char device[128];
73
74	/*
75	 * Open device file for reading.
76	 */
77	snprintf(device, sizeof(device), DEVICE, unit);
78	fd = open(device, O_RDONLY);
79	if (fd == -1) {
80		snprintf(device, sizeof(device), OLDDEVICE, unit);
81		fd = open(device, O_RDONLY);
82	}
83#ifdef DEBUG
84	if (debug)
85		printf ("starting PCF with device %s\n",device);
86#endif
87	if (fd == -1) {
88		return (0);
89	}
90
91	pp = peer->procptr;
92	pp->io.clock_recv = noentry;
93	pp->io.srcclock = peer;
94	pp->io.datalen = 0;
95	pp->io.fd = fd;
96
97	/*
98	 * Initialize miscellaneous variables
99	 */
100	peer->precision = PRECISION;
101	pp->clockdesc = DESCRIPTION;
102	/* one transmission takes 172.5 milliseconds since the radio clock
103	   transmits 69 bits with a period of 2.5 milliseconds per bit */
104	pp->fudgetime1 = 0.1725;
105	memcpy((char *)&pp->refid, REFID, 4);
106
107	return (1);
108}
109
110
111/*
112 * pcf_shutdown - shut down the clock
113 */
114static void
115pcf_shutdown(
116	int unit,
117	struct peer *peer
118	)
119{
120	struct refclockproc *pp;
121
122	pp = peer->procptr;
123	if (NULL != pp)
124		close(pp->io.fd);
125}
126
127
128/*
129 * pcf_poll - called by the transmit procedure
130 */
131static void
132pcf_poll(
133	int unit,
134	struct peer *peer
135	)
136{
137	struct refclockproc *pp;
138	char buf[LENPCF];
139	struct tm tm, *tp;
140	time_t t;
141
142	pp = peer->procptr;
143
144	buf[0] = 0;
145	if (read(pp->io.fd, buf, sizeof(buf)) < (ssize_t)sizeof(buf) || buf[0] != 9) {
146		refclock_report(peer, CEVNT_FAULT);
147		return;
148	}
149
150	ZERO(tm);
151
152	tm.tm_mday = buf[11] * 10 + buf[10];
153	tm.tm_mon = buf[13] * 10 + buf[12] - 1;
154	tm.tm_year = buf[15] * 10 + buf[14];
155	tm.tm_hour = buf[7] * 10 + buf[6];
156	tm.tm_min = buf[5] * 10 + buf[4];
157	tm.tm_sec = buf[3] * 10 + buf[2];
158	tm.tm_isdst = (buf[8] & 1) ? 1 : (buf[8] & 2) ? 0 : -1;
159
160	/*
161	 * Y2K convert the 2-digit year
162	 */
163	if (tm.tm_year < 99)
164		tm.tm_year += 100;
165
166	t = mktime(&tm);
167	if (t == (time_t) -1) {
168		refclock_report(peer, CEVNT_BADTIME);
169		return;
170	}
171
172#if defined(__GLIBC__) && defined(_BSD_SOURCE)
173	if ((tm.tm_isdst > 0 && tm.tm_gmtoff != 7200)
174	    || (tm.tm_isdst == 0 && tm.tm_gmtoff != 3600)
175	    || tm.tm_isdst < 0) {
176#ifdef DEBUG
177		if (debug)
178			printf ("local time zone not set to CET/CEST\n");
179#endif
180		refclock_report(peer, CEVNT_BADTIME);
181		return;
182	}
183#endif
184
185	pp->lencode = strftime(pp->a_lastcode, BMAX, "%Y %m %d %H %M %S", &tm);
186
187#if defined(_REENTRANT) || defined(_THREAD_SAFE)
188	tp = gmtime_r(&t, &tm);
189#else
190	tp = gmtime(&t);
191#endif
192	if (!tp) {
193		refclock_report(peer, CEVNT_FAULT);
194		return;
195	}
196
197	get_systime(&pp->lastrec);
198	pp->polls++;
199	pp->year = tp->tm_year + 1900;
200	pp->day = tp->tm_yday + 1;
201	pp->hour = tp->tm_hour;
202	pp->minute = tp->tm_min;
203	pp->second = tp->tm_sec;
204	pp->nsec = buf[16] * 31250000;
205	if (buf[17] & 1)
206		pp->nsec += 500000000;
207
208#ifdef DEBUG
209	if (debug)
210		printf ("pcf%d: time is %04d/%02d/%02d %02d:%02d:%02d UTC\n",
211			unit, pp->year, tp->tm_mon + 1, tp->tm_mday, pp->hour,
212			pp->minute, pp->second);
213#endif
214
215	if (!refclock_process(pp)) {
216		refclock_report(peer, CEVNT_BADTIME);
217		return;
218	}
219	record_clock_stats(&peer->srcadr, pp->a_lastcode);
220	if ((buf[1] & 1) && !(pp->sloppyclockflag & CLK_FLAG2))
221		pp->leap = LEAP_NOTINSYNC;
222	else
223		pp->leap = LEAP_NOWARNING;
224	pp->lastref = pp->lastrec;
225	refclock_receive(peer);
226}
227#else
228int refclock_pcf_bs;
229#endif /* REFCLOCK */
230