xref: /freebsd/contrib/ntp/ntpd/refclock_pcf.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1 /*
2  * refclock_pcf - clock driver for the Conrad parallel port radio clock
3  */
4 
5 #ifdef HAVE_CONFIG_H
6 # include <config.h>
7 #endif
8 
9 #if defined(REFCLOCK) && defined(CLOCK_PCF)
10 
11 #include "ntpd.h"
12 #include "ntp_io.h"
13 #include "ntp_refclock.h"
14 #include "ntp_calendar.h"
15 #include "ntp_stdlib.h"
16 
17 /*
18  * This driver supports the parallel port radio clock sold by Conrad
19  * Electronic under order numbers 967602 and 642002.
20  *
21  * It requires that the local timezone be CET/CEST and that the pcfclock
22  * device driver be installed.  A device driver for Linux is available at
23  * http://home.pages.de/~voegele/pcf.html.  Information about a FreeBSD
24  * driver is available at http://schumann.cx/pcfclock/.
25  */
26 
27 /*
28  * Interface definitions
29  */
30 #define	DEVICE		"/dev/pcfclocks/%d"
31 #define	OLDDEVICE	"/dev/pcfclock%d"
32 #define	PRECISION	(-1)	/* precision assumed (about 0.5 s) */
33 #define REFID		"PCF"
34 #define DESCRIPTION	"Conrad parallel port radio clock"
35 
36 #define LENPCF		18	/* timecode length */
37 
38 /*
39  * Function prototypes
40  */
41 static	int 	pcf_start 		(int, struct peer *);
42 static	void	pcf_shutdown		(int, struct peer *);
43 static	void	pcf_poll		(int, struct peer *);
44 
45 /*
46  * Transfer vector
47  */
48 struct  refclock refclock_pcf = {
49 	pcf_start,              /* start up driver */
50 	pcf_shutdown,           /* shut down driver */
51 	pcf_poll,               /* transmit poll message */
52 	noentry,                /* not used */
53 	noentry,                /* initialize driver (not used) */
54 	noentry,                /* not used */
55 	NOFLAGS                 /* not used */
56 };
57 
58 
59 /*
60  * pcf_start - open the device and initialize data for processing
61  */
62 static int
63 pcf_start(
64      	int unit,
65 	struct peer *peer
66 	)
67 {
68 	struct refclockproc *pp;
69 	int fd;
70 	char device[128];
71 
72 	/*
73 	 * Open device file for reading.
74 	 */
75 	snprintf(device, sizeof(device), DEVICE, unit);
76 	fd = open(device, O_RDONLY);
77 	if (fd == -1) {
78 		snprintf(device, sizeof(device), OLDDEVICE, unit);
79 		fd = open(device, O_RDONLY);
80 	}
81 #ifdef DEBUG
82 	if (debug)
83 		printf ("starting PCF with device %s\n",device);
84 #endif
85 	if (fd == -1) {
86 		return (0);
87 	}
88 
89 	pp = peer->procptr;
90 	pp->io.clock_recv = noentry;
91 	pp->io.srcclock = peer;
92 	pp->io.datalen = 0;
93 	pp->io.fd = fd;
94 
95 	/*
96 	 * Initialize miscellaneous variables
97 	 */
98 	peer->precision = PRECISION;
99 	pp->clockdesc = DESCRIPTION;
100 	/* one transmission takes 172.5 milliseconds since the radio clock
101 	   transmits 69 bits with a period of 2.5 milliseconds per bit */
102 	pp->fudgetime1 = 0.1725;
103 	memcpy((char *)&pp->refid, REFID, 4);
104 
105 	return (1);
106 }
107 
108 
109 /*
110  * pcf_shutdown - shut down the clock
111  */
112 static void
113 pcf_shutdown(
114 	int unit,
115 	struct peer *peer
116 	)
117 {
118 	struct refclockproc *pp;
119 
120 	pp = peer->procptr;
121 	if (NULL != pp)
122 		close(pp->io.fd);
123 }
124 
125 
126 /*
127  * pcf_poll - called by the transmit procedure
128  */
129 static void
130 pcf_poll(
131 	int unit,
132 	struct peer *peer
133 	)
134 {
135 	struct refclockproc *pp;
136 	char buf[LENPCF];
137 	struct tm tm, *tp;
138 	time_t t;
139 
140 	pp = peer->procptr;
141 
142 	buf[0] = 0;
143 	if (read(pp->io.fd, buf, sizeof(buf)) < (ssize_t)sizeof(buf) || buf[0] != 9) {
144 		refclock_report(peer, CEVNT_FAULT);
145 		return;
146 	}
147 
148 	ZERO(tm);
149 
150 	tm.tm_mday = buf[11] * 10 + buf[10];
151 	tm.tm_mon = buf[13] * 10 + buf[12] - 1;
152 	tm.tm_year = buf[15] * 10 + buf[14];
153 	tm.tm_hour = buf[7] * 10 + buf[6];
154 	tm.tm_min = buf[5] * 10 + buf[4];
155 	tm.tm_sec = buf[3] * 10 + buf[2];
156 	tm.tm_isdst = (buf[8] & 1) ? 1 : (buf[8] & 2) ? 0 : -1;
157 
158 	/*
159 	 * Y2K convert the 2-digit year
160 	 */
161 	if (tm.tm_year < 99)
162 		tm.tm_year += 100;
163 
164 	t = mktime(&tm);
165 	if (t == (time_t) -1) {
166 		refclock_report(peer, CEVNT_BADTIME);
167 		return;
168 	}
169 
170 #if defined(__GLIBC__) && defined(_BSD_SOURCE)
171 	if ((tm.tm_isdst > 0 && tm.tm_gmtoff != 7200)
172 	    || (tm.tm_isdst == 0 && tm.tm_gmtoff != 3600)
173 	    || tm.tm_isdst < 0) {
174 #ifdef DEBUG
175 		if (debug)
176 			printf ("local time zone not set to CET/CEST\n");
177 #endif
178 		refclock_report(peer, CEVNT_BADTIME);
179 		return;
180 	}
181 #endif
182 
183 	pp->lencode = strftime(pp->a_lastcode, BMAX, "%Y %m %d %H %M %S", &tm);
184 
185 #if defined(_REENTRANT) || defined(_THREAD_SAFE)
186 	tp = gmtime_r(&t, &tm);
187 #else
188 	tp = gmtime(&t);
189 #endif
190 	if (!tp) {
191 		refclock_report(peer, CEVNT_FAULT);
192 		return;
193 	}
194 
195 	get_systime(&pp->lastrec);
196 	pp->polls++;
197 	pp->year = tp->tm_year + 1900;
198 	pp->day = tp->tm_yday + 1;
199 	pp->hour = tp->tm_hour;
200 	pp->minute = tp->tm_min;
201 	pp->second = tp->tm_sec;
202 	pp->nsec = buf[16] * 31250000;
203 	if (buf[17] & 1)
204 		pp->nsec += 500000000;
205 
206 #ifdef DEBUG
207 	if (debug)
208 		printf ("pcf%d: time is %04d/%02d/%02d %02d:%02d:%02d UTC\n",
209 			unit, pp->year, tp->tm_mon + 1, tp->tm_mday, pp->hour,
210 			pp->minute, pp->second);
211 #endif
212 
213 	if (!refclock_process(pp)) {
214 		refclock_report(peer, CEVNT_BADTIME);
215 		return;
216 	}
217 	record_clock_stats(&peer->srcadr, pp->a_lastcode);
218 	if ((buf[1] & 1) && !(pp->sloppyclockflag & CLK_FLAG2))
219 		pp->leap = LEAP_NOTINSYNC;
220 	else
221 		pp->leap = LEAP_NOWARNING;
222 	pp->lastref = pp->lastrec;
223 	refclock_receive(peer);
224 }
225 #else
226 int refclock_pcf_bs;
227 #endif /* REFCLOCK */
228