xref: /freebsd/contrib/ntp/parseutil/dcfd.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
1 /*
2  * /src/NTP/ntp-4/parseutil/dcfd.c,v 4.9 1999/02/28 13:06:27 kardel RELEASE_19990228_A
3  *
4  * dcfd.c,v 4.9 1999/02/28 13:06:27 kardel RELEASE_19990228_A
5  *
6  * DCF77 100/200ms pulse synchronisation daemon program (via 50Baud serial line)
7  *
8  * Features:
9  *  DCF77 decoding
10  *  simple NTP loopfilter logic for local clock
11  *  interactive display for debugging
12  *
13  * Lacks:
14  *  Leap second handling (at that level you should switch to NTP Version 4 - really!)
15  *
16  * Copyright (C) 1995-1999 by Frank Kardel <kardel@acm.org>
17  * Copyright (C) 1993-1994 by Frank Kardel
18  * Friedrich-Alexander Universit�t Erlangen-N�rnberg, Germany
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23  *
24  * This program may not be sold or used for profit without prior
25  * written consent of the author.
26  */
27 
28 #ifdef HAVE_CONFIG_H
29 # include <config.h>
30 #endif
31 
32 #include <unistd.h>
33 #include <stdio.h>
34 #include <fcntl.h>
35 #include <sys/types.h>
36 #include <sys/time.h>
37 #include <signal.h>
38 #include <syslog.h>
39 #include <time.h>
40 
41 /*
42  * NTP compilation environment
43  */
44 #include "ntp_stdlib.h"
45 #include "ntpd.h"   /* indirectly include ntp.h to get YEAR_PIVOT   Y2KFixes */
46 
47 /*
48  * select which terminal handling to use (currently only SysV variants)
49  */
50 #if defined(HAVE_TERMIOS_H) || defined(STREAM)
51 #include <termios.h>
52 #define TTY_GETATTR(_FD_, _ARG_) tcgetattr((_FD_), (_ARG_))
53 #define TTY_SETATTR(_FD_, _ARG_) tcsetattr((_FD_), TCSANOW, (_ARG_))
54 #else  /* not HAVE_TERMIOS_H || STREAM */
55 # if defined(HAVE_TERMIO_H) || defined(HAVE_SYSV_TTYS)
56 #  include <termio.h>
57 #  define TTY_GETATTR(_FD_, _ARG_) ioctl((_FD_), TCGETA, (_ARG_))
58 #  define TTY_SETATTR(_FD_, _ARG_) ioctl((_FD_), TCSETAW, (_ARG_))
59 # endif/* HAVE_TERMIO_H || HAVE_SYSV_TTYS */
60 #endif /* not HAVE_TERMIOS_H || STREAM */
61 
62 
63 #ifndef TTY_GETATTR
64 #include "Bletch: MUST DEFINE ONE OF 'HAVE_TERMIOS_H' or 'HAVE_TERMIO_H'"
65 #endif
66 
67 #ifndef days_per_year
68 #define days_per_year(_x_) (((_x_) % 4) ? 365 : (((_x_) % 400) ? 365 : 366))
69 #endif
70 
71 #define timernormalize(_a_) \
72 	if ((_a_)->tv_usec >= 1000000) \
73 	{ \
74 		(_a_)->tv_sec  += (_a_)->tv_usec / 1000000; \
75 		(_a_)->tv_usec  = (_a_)->tv_usec % 1000000; \
76 	} \
77 	if ((_a_)->tv_usec < 0) \
78 	{ \
79 		(_a_)->tv_sec  -= 1 + (-(_a_)->tv_usec / 1000000); \
80 		(_a_)->tv_usec = 999999 - (-(_a_)->tv_usec - 1); \
81 	}
82 
83 #ifdef timeradd
84 #undef timeradd
85 #endif
86 #define timeradd(_a_, _b_) \
87 	(_a_)->tv_sec  += (_b_)->tv_sec; \
88 	(_a_)->tv_usec += (_b_)->tv_usec; \
89 	timernormalize((_a_))
90 
91 #ifdef timersub
92 #undef timersub
93 #endif
94 #define timersub(_a_, _b_) \
95 	(_a_)->tv_sec  -= (_b_)->tv_sec; \
96 	(_a_)->tv_usec -= (_b_)->tv_usec; \
97 	timernormalize((_a_))
98 
99 /*
100  * debug macros
101  */
102 #define PRINTF if (interactive) printf
103 #define LPRINTF if (interactive && loop_filter_debug) printf
104 
105 #ifdef DEBUG
106 #define dprintf(_x_) LPRINTF _x_
107 #else
108 #define dprintf(_x_)
109 #endif
110 
111 #ifdef DECL_ERRNO
112      extern int errno;
113 #endif
114 
115 /*
116  * display received data (avoids also detaching from tty)
117  */
118 static int interactive = 0;
119 
120 /*
121  * display loopfilter (clock control) variables
122  */
123 static int loop_filter_debug = 0;
124 
125 /*
126  * do not set/adjust system time
127  */
128 static int no_set = 0;
129 
130 /*
131  * time that passes between start of DCF impulse and time stamping (fine
132  * adjustment) in microseconds (receiver/OS dependent)
133  */
134 #define DEFAULT_DELAY	230000	/* rough estimate */
135 
136 /*
137  * The two states we can be in - eithe we receive nothing
138  * usable or we have the correct time
139  */
140 #define NO_SYNC		0x01
141 #define SYNC		0x02
142 
143 static int    sync_state = NO_SYNC;
144 static time_t last_sync;
145 
146 static unsigned long ticks = 0;
147 
148 static char pat[] = "-\\|/";
149 
150 #define LINES		(24-2)	/* error lines after which the two headlines are repeated */
151 
152 #define MAX_UNSYNC	(10*60)	/* allow synchronisation loss for 10 minutes */
153 #define NOTICE_INTERVAL (20*60)	/* mention missing synchronisation every 20 minutes */
154 
155 /*
156  * clock adjustment PLL - see NTP protocol spec (RFC1305) for details
157  */
158 
159 #define USECSCALE	10
160 #define TIMECONSTANT	2
161 #define ADJINTERVAL	0
162 #define FREQ_WEIGHT	18
163 #define PHASE_WEIGHT	7
164 #define MAX_DRIFT	0x3FFFFFFF
165 
166 #define R_SHIFT(_X_, _Y_) (((_X_) < 0) ? -(-(_X_) >> (_Y_)) : ((_X_) >> (_Y_)))
167 
168 static struct timeval max_adj_offset = { 0, 128000 };
169 
170 static long clock_adjust = 0;	/* current adjustment value (usec * 2^USECSCALE) */
171 static long accum_drift   = 0;	/* accumulated drift value  (usec / ADJINTERVAL) */
172 static long adjustments  = 0;
173 static char skip_adjust  = 1;	/* discard first adjustment (bad samples) */
174 
175 /*
176  * DCF77 state flags
177  */
178 #define DCFB_ANNOUNCE           0x0001 /* switch time zone warning (DST switch) */
179 #define DCFB_DST                0x0002 /* DST in effect */
180 #define DCFB_LEAP		0x0004 /* LEAP warning (1 hour prior to occurrence) */
181 #define DCFB_ALTERNATE		0x0008 /* alternate antenna used */
182 
183 struct clocktime		/* clock time broken up from time code */
184 {
185 	long wday;		/* Day of week: 1: Monday - 7: Sunday */
186 	long day;
187 	long month;
188 	long year;
189 	long hour;
190 	long minute;
191 	long second;
192 	long usecond;
193 	long utcoffset;	/* in minutes */
194 	long flags;		/* current clock status  (DCF77 state flags) */
195 };
196 
197 typedef struct clocktime clocktime_t;
198 
199 /*
200  * (usually) quick constant multiplications
201  */
202 #define TIMES10(_X_) (((_X_) << 3) + ((_X_) << 1))	/* *8 + *2 */
203 #define TIMES24(_X_) (((_X_) << 4) + ((_X_) << 3))      /* *16 + *8 */
204 #define TIMES60(_X_) ((((_X_) << 4)  - (_X_)) << 2)     /* *(16 - 1) *4 */
205 /*
206  * generic l_abs() function
207  */
208 #define l_abs(_x_)     (((_x_) < 0) ? -(_x_) : (_x_))
209 
210 /*
211  * conversion related return/error codes
212  */
213 #define CVT_MASK	0x0000000F /* conversion exit code */
214 #define   CVT_NONE	0x00000001 /* format not applicable */
215 #define   CVT_FAIL	0x00000002 /* conversion failed - error code returned */
216 #define   CVT_OK	0x00000004 /* conversion succeeded */
217 #define CVT_BADFMT	0x00000010 /* general format error - (unparsable) */
218 #define CVT_BADDATE	0x00000020 /* invalid date */
219 #define CVT_BADTIME	0x00000040 /* invalid time */
220 
221 /*
222  * DCF77 raw time code
223  *
224  * From "Zur Zeit", Physikalisch-Technische Bundesanstalt (PTB), Braunschweig
225  * und Berlin, Maerz 1989
226  *
227  * Timecode transmission:
228  * AM:
229  *	time marks are send every second except for the second before the
230  *	next minute mark
231  *	time marks consist of a reduction of transmitter power to 25%
232  *	of the nominal level
233  *	the falling edge is the time indication (on time)
234  *	time marks of a 100ms duration constitute a logical 0
235  *	time marks of a 200ms duration constitute a logical 1
236  * FM:
237  *	see the spec. (basically a (non-)inverted psuedo random phase shift)
238  *
239  * Encoding:
240  * Second	Contents
241  * 0  - 10	AM: free, FM: 0
242  * 11 - 14	free
243  * 15		R     - alternate antenna
244  * 16		A1    - expect zone change (1 hour before)
245  * 17 - 18	Z1,Z2 - time zone
246  *		 0  0 illegal
247  *		 0  1 MEZ  (MET)
248  *		 1  0 MESZ (MED, MET DST)
249  *		 1  1 illegal
250  * 19		A2    - expect leap insertion/deletion (1 hour before)
251  * 20		S     - start of time code (1)
252  * 21 - 24	M1    - BCD (lsb first) Minutes
253  * 25 - 27	M10   - BCD (lsb first) 10 Minutes
254  * 28		P1    - Minute Parity (even)
255  * 29 - 32	H1    - BCD (lsb first) Hours
256  * 33 - 34      H10   - BCD (lsb first) 10 Hours
257  * 35		P2    - Hour Parity (even)
258  * 36 - 39	D1    - BCD (lsb first) Days
259  * 40 - 41	D10   - BCD (lsb first) 10 Days
260  * 42 - 44	DW    - BCD (lsb first) day of week (1: Monday -> 7: Sunday)
261  * 45 - 49	MO    - BCD (lsb first) Month
262  * 50           MO0   - 10 Months
263  * 51 - 53	Y1    - BCD (lsb first) Years
264  * 54 - 57	Y10   - BCD (lsb first) 10 Years
265  * 58 		P3    - Date Parity (even)
266  * 59		      - usually missing (minute indication), except for leap insertion
267  */
268 
269 /*-----------------------------------------------------------------------
270  * conversion table to map DCF77 bit stream into data fields.
271  * Encoding:
272  *   Each field of the DCF77 code is described with two adjacent entries in
273  *   this table. The first entry specifies the offset into the DCF77 data stream
274  *   while the length is given as the difference between the start index and
275  *   the start index of the following field.
276  */
277 static struct rawdcfcode
278 {
279 	char offset;			/* start bit */
280 } rawdcfcode[] =
281 {
282 	{  0 }, { 15 }, { 16 }, { 17 }, { 19 }, { 20 }, { 21 }, { 25 }, { 28 }, { 29 },
283 	{ 33 }, { 35 }, { 36 }, { 40 }, { 42 }, { 45 }, { 49 }, { 50 }, { 54 }, { 58 }, { 59 }
284 };
285 
286 /*-----------------------------------------------------------------------
287  * symbolic names for the fields of DCF77 describes in "rawdcfcode".
288  * see comment above for the structure of the DCF77 data
289  */
290 #define DCF_M	0
291 #define DCF_R	1
292 #define DCF_A1	2
293 #define DCF_Z	3
294 #define DCF_A2	4
295 #define DCF_S	5
296 #define DCF_M1	6
297 #define DCF_M10	7
298 #define DCF_P1	8
299 #define DCF_H1	9
300 #define DCF_H10	10
301 #define DCF_P2	11
302 #define DCF_D1	12
303 #define DCF_D10	13
304 #define DCF_DW	14
305 #define DCF_MO	15
306 #define DCF_MO0	16
307 #define DCF_Y1	17
308 #define DCF_Y10	18
309 #define DCF_P3	19
310 
311 /*-----------------------------------------------------------------------
312  * parity field table (same encoding as rawdcfcode)
313  * This table describes the sections of the DCF77 code that are
314  * parity protected
315  */
316 static struct partab
317 {
318 	char offset;			/* start bit of parity field */
319 } partab[] =
320 {
321 	{ 21 }, { 29 }, { 36 }, { 59 }
322 };
323 
324 /*-----------------------------------------------------------------------
325  * offsets for parity field descriptions
326  */
327 #define DCF_P_P1	0
328 #define DCF_P_P2	1
329 #define DCF_P_P3	2
330 
331 /*-----------------------------------------------------------------------
332  * legal values for time zone information
333  */
334 #define DCF_Z_MET 0x2
335 #define DCF_Z_MED 0x1
336 
337 /*-----------------------------------------------------------------------
338  * symbolic representation if the DCF77 data stream
339  */
340 static struct dcfparam
341 {
342 	unsigned char onebits[60];
343 	unsigned char zerobits[60];
344 } dcfparam =
345 {
346 	"###############RADMLS1248124P124812P1248121241248112481248P", /* 'ONE' representation */
347 	"--------------------s-------p------p----------------------p"  /* 'ZERO' representation */
348 };
349 
350 /*-----------------------------------------------------------------------
351  * extract a bitfield from DCF77 datastream
352  * All numeric fields are LSB first.
353  * buf holds a pointer to a DCF77 data buffer in symbolic
354  *     representation
355  * idx holds the index to the field description in rawdcfcode
356  */
357 static unsigned long
358 ext_bf(
359 	register unsigned char *buf,
360 	register int   idx
361 	)
362 {
363 	register unsigned long sum = 0;
364 	register int i, first;
365 
366 	first = rawdcfcode[idx].offset;
367 
368 	for (i = rawdcfcode[idx+1].offset - 1; i >= first; i--)
369 	{
370 		sum <<= 1;
371 		sum |= (buf[i] != dcfparam.zerobits[i]);
372 	}
373 	return sum;
374 }
375 
376 /*-----------------------------------------------------------------------
377  * check even parity integrity for a bitfield
378  *
379  * buf holds a pointer to a DCF77 data buffer in symbolic
380  *     representation
381  * idx holds the index to the field description in partab
382  */
383 static unsigned
384 pcheck(
385 	register unsigned char *buf,
386 	register int   idx
387 	)
388 {
389 	register int i,last;
390 	register unsigned psum = 1;
391 
392 	last = partab[idx+1].offset;
393 
394 	for (i = partab[idx].offset; i < last; i++)
395 	    psum ^= (buf[i] != dcfparam.zerobits[i]);
396 
397 	return psum;
398 }
399 
400 /*-----------------------------------------------------------------------
401  * convert a DCF77 data buffer into wall clock time + flags
402  *
403  * buffer holds a pointer to a DCF77 data buffer in symbolic
404  *        representation
405  * size   describes the length of DCF77 information in bits (represented
406  *        as chars in symbolic notation
407  * clock  points to a wall clock time description of the DCF77 data (result)
408  */
409 static unsigned long
410 convert_rawdcf(
411 	       unsigned char   *buffer,
412 	       int              size,
413 	       clocktime_t     *clock_time
414 	       )
415 {
416 	if (size < 57)
417 	{
418 		PRINTF("%-30s", "*** INCOMPLETE");
419 		return CVT_NONE;
420 	}
421 
422 	/*
423 	 * check Start and Parity bits
424 	 */
425 	if ((ext_bf(buffer, DCF_S) == 1) &&
426 	    pcheck(buffer, DCF_P_P1) &&
427 	    pcheck(buffer, DCF_P_P2) &&
428 	    pcheck(buffer, DCF_P_P3))
429 	{
430 		/*
431 		 * buffer OK - extract all fields and build wall clock time from them
432 		 */
433 
434 		clock_time->flags  = 0;
435 		clock_time->usecond= 0;
436 		clock_time->second = 0;
437 		clock_time->minute = ext_bf(buffer, DCF_M10);
438 		clock_time->minute = TIMES10(clock_time->minute) + ext_bf(buffer, DCF_M1);
439 		clock_time->hour   = ext_bf(buffer, DCF_H10);
440 		clock_time->hour   = TIMES10(clock_time->hour)   + ext_bf(buffer, DCF_H1);
441 		clock_time->day    = ext_bf(buffer, DCF_D10);
442 		clock_time->day    = TIMES10(clock_time->day)    + ext_bf(buffer, DCF_D1);
443 		clock_time->month  = ext_bf(buffer, DCF_MO0);
444 		clock_time->month  = TIMES10(clock_time->month)  + ext_bf(buffer, DCF_MO);
445 		clock_time->year   = ext_bf(buffer, DCF_Y10);
446 		clock_time->year   = TIMES10(clock_time->year)   + ext_bf(buffer, DCF_Y1);
447 		clock_time->wday   = ext_bf(buffer, DCF_DW);
448 
449 		/*
450 		 * determine offset to UTC by examining the time zone
451 		 */
452 		switch (ext_bf(buffer, DCF_Z))
453 		{
454 		    case DCF_Z_MET:
455 			clock_time->utcoffset = -60;
456 			break;
457 
458 		    case DCF_Z_MED:
459 			clock_time->flags     |= DCFB_DST;
460 			clock_time->utcoffset  = -120;
461 			break;
462 
463 		    default:
464 			PRINTF("%-30s", "*** BAD TIME ZONE");
465 			return CVT_FAIL|CVT_BADFMT;
466 		}
467 
468 		/*
469 		 * extract various warnings from DCF77
470 		 */
471 		if (ext_bf(buffer, DCF_A1))
472 		    clock_time->flags |= DCFB_ANNOUNCE;
473 
474 		if (ext_bf(buffer, DCF_A2))
475 		    clock_time->flags |= DCFB_LEAP;
476 
477 		if (ext_bf(buffer, DCF_R))
478 		    clock_time->flags |= DCFB_ALTERNATE;
479 
480 		return CVT_OK;
481 	}
482 	else
483 	{
484 		/*
485 		 * bad format - not for us
486 		 */
487 		PRINTF("%-30s", "*** BAD FORMAT (invalid/parity)");
488 		return CVT_FAIL|CVT_BADFMT;
489 	}
490 }
491 
492 /*-----------------------------------------------------------------------
493  * raw dcf input routine - fix up 50 baud
494  * characters for 1/0 decision
495  */
496 static unsigned long
497 cvt_rawdcf(
498 	   unsigned char   *buffer,
499 	   int              size,
500 	   clocktime_t     *clock_time
501 	   )
502 {
503 	register unsigned char *s = buffer;
504 	register unsigned char *e = buffer + size;
505 	register unsigned char *b = dcfparam.onebits;
506 	register unsigned char *c = dcfparam.zerobits;
507 	register unsigned rtc = CVT_NONE;
508 	register unsigned int i, lowmax, highmax, cutoff, span;
509 #define BITS 9
510 	unsigned char     histbuf[BITS];
511 	/*
512 	 * the input buffer contains characters with runs of consecutive
513 	 * bits set. These set bits are an indication of the DCF77 pulse
514 	 * length. We assume that we receive the pulse at 50 Baud. Thus
515 	 * a 100ms pulse would generate a 4 bit train (20ms per bit and
516 	 * start bit)
517 	 * a 200ms pulse would create all zeroes (and probably a frame error)
518 	 *
519 	 * The basic idea is that on corret reception we must have two
520 	 * maxima in the pulse length distribution histogram. (one for
521 	 * the zero representing pulses and one for the one representing
522 	 * pulses)
523 	 * There will always be ones in the datastream, thus we have to see
524 	 * two maxima.
525 	 * The best point to cut for a 1/0 decision is the minimum between those
526 	 * between the maxima. The following code tries to find this cutoff point.
527 	 */
528 
529 	/*
530 	 * clear histogram buffer
531 	 */
532 	for (i = 0; i < BITS; i++)
533 	{
534 		histbuf[i] = 0;
535 	}
536 
537 	cutoff = 0;
538 	lowmax = 0;
539 
540 	/*
541 	 * convert sequences of set bits into bits counts updating
542 	 * the histogram alongway
543 	 */
544 	while (s < e)
545 	{
546 		register unsigned int ch = *s ^ 0xFF;
547 		/*
548 		 * check integrity and update histogramm
549 		 */
550 		if (!((ch+1) & ch) || !*s)
551 		{
552 			/*
553 			 * character ok
554 			 */
555 			for (i = 0; ch; i++)
556 			{
557 				ch >>= 1;
558 			}
559 
560 			*s = i;
561 			histbuf[i]++;
562 			cutoff += i;
563 			lowmax++;
564 		}
565 		else
566 		{
567 			/*
568 			 * invalid character (no consecutive bit sequence)
569 			 */
570 			dprintf(("parse: cvt_rawdcf: character check for 0x%x@%d FAILED\n", *s, s - buffer));
571 			*s = (unsigned char)~0;
572 			rtc = CVT_FAIL|CVT_BADFMT;
573 		}
574 		s++;
575 	}
576 
577 	/*
578 	 * first cutoff estimate (average bit count - must be between both
579 	 * maxima)
580 	 */
581 	if (lowmax)
582 	{
583 		cutoff /= lowmax;
584 	}
585 	else
586 	{
587 		cutoff = 4;	/* doesn't really matter - it'll fail anyway, but gives error output */
588 	}
589 
590 	dprintf(("parse: cvt_rawdcf: average bit count: %d\n", cutoff));
591 
592 	lowmax = 0;  /* weighted sum */
593 	highmax = 0; /* bitcount */
594 
595 	/*
596 	 * collect weighted sum of lower bits (left of initial guess)
597 	 */
598 	dprintf(("parse: cvt_rawdcf: histogram:"));
599 	for (i = 0; i <= cutoff; i++)
600 	{
601 		lowmax  += histbuf[i] * i;
602 		highmax += histbuf[i];
603 		dprintf((" %d", histbuf[i]));
604 	}
605 	dprintf((" <M>"));
606 
607 	/*
608 	 * round up
609 	 */
610 	lowmax += highmax / 2;
611 
612 	/*
613 	 * calculate lower bit maximum (weighted sum / bit count)
614 	 *
615 	 * avoid divide by zero
616 	 */
617 	if (highmax)
618 	{
619 		lowmax /= highmax;
620 	}
621 	else
622 	{
623 		lowmax = 0;
624 	}
625 
626 	highmax = 0; /* weighted sum of upper bits counts */
627 	cutoff = 0;  /* bitcount */
628 
629 	/*
630 	 * collect weighted sum of lower bits (right of initial guess)
631 	 */
632 	for (; i < BITS; i++)
633 	{
634 		highmax+=histbuf[i] * i;
635 		cutoff +=histbuf[i];
636 		dprintf((" %d", histbuf[i]));
637 	}
638 	dprintf(("\n"));
639 
640 	/*
641 	 * determine upper maximum (weighted sum / bit count)
642 	 */
643 	if (cutoff)
644 	{
645 		highmax /= cutoff;
646 	}
647 	else
648 	{
649 		highmax = BITS-1;
650 	}
651 
652 	/*
653 	 * following now holds:
654 	 * lowmax <= cutoff(initial guess) <= highmax
655 	 * best cutoff is the minimum nearest to higher bits
656 	 */
657 
658 	/*
659 	 * find the minimum between lowmax and highmax (detecting
660 	 * possibly a minimum span)
661 	 */
662 	span = cutoff = lowmax;
663 	for (i = lowmax; i <= highmax; i++)
664 	{
665 		if (histbuf[cutoff] > histbuf[i])
666 		{
667 			/*
668 			 * got a new minimum move beginning of minimum (cutoff) and
669 			 * end of minimum (span) there
670 			 */
671 			cutoff = span = i;
672 		}
673 		else
674 		    if (histbuf[cutoff] == histbuf[i])
675 		    {
676 			    /*
677 			     * minimum not better yet - but it spans more than
678 			     * one bit value - follow it
679 			     */
680 			    span = i;
681 		    }
682 	}
683 
684 	/*
685 	 * cutoff point for 1/0 decision is the middle of the minimum section
686 	 * in the histogram
687 	 */
688 	cutoff = (cutoff + span) / 2;
689 
690 	dprintf(("parse: cvt_rawdcf: lower maximum %d, higher maximum %d, cutoff %d\n", lowmax, highmax, cutoff));
691 
692 	/*
693 	 * convert the bit counts to symbolic 1/0 information for data conversion
694 	 */
695 	s = buffer;
696 	while ((s < e) && *c && *b)
697 	{
698 		if (*s == (unsigned char)~0)
699 		{
700 			/*
701 			 * invalid character
702 			 */
703 			*s = '?';
704 		}
705 		else
706 		{
707 			/*
708 			 * symbolic 1/0 representation
709 			 */
710 			*s = (*s >= cutoff) ? *b : *c;
711 		}
712 		s++;
713 		b++;
714 		c++;
715 	}
716 
717 	/*
718 	 * if everything went well so far return the result of the symbolic
719 	 * conversion routine else just the accumulated errors
720 	 */
721 	if (rtc != CVT_NONE)
722 	{
723 		PRINTF("%-30s", "*** BAD DATA");
724 	}
725 
726 	return (rtc == CVT_NONE) ? convert_rawdcf(buffer, size, clock_time) : rtc;
727 }
728 
729 /*-----------------------------------------------------------------------
730  * convert a wall clock time description of DCF77 to a Unix time (seconds
731  * since 1.1. 1970 UTC)
732  */
733 static time_t
734 dcf_to_unixtime(
735 		clocktime_t   *clock_time,
736 		unsigned *cvtrtc
737 		)
738 {
739 #define SETRTC(_X_)	{ if (cvtrtc) *cvtrtc = (_X_); }
740 	static int days_of_month[] =
741 	{
742 		0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
743 	};
744 	register int i;
745 	time_t t;
746 
747 	/*
748 	 * map 2 digit years to 19xx (DCF77 is a 20th century item)
749 	 */
750 	if ( clock_time->year < YEAR_PIVOT ) 	/* in case of	   Y2KFixes [ */
751 		clock_time->year += 100;	/* *year%100, make tm_year */
752 						/* *(do we need this?) */
753 	if ( clock_time->year < YEAR_BREAK )	/* (failsafe if) */
754 	    clock_time->year += 1900;				/* Y2KFixes ] */
755 
756 	/*
757 	 * must have been a really bad year code - drop it
758 	 */
759 	if (clock_time->year < (YEAR_PIVOT + 1900) )		/* Y2KFixes */
760 	{
761 		SETRTC(CVT_FAIL|CVT_BADDATE);
762 		return -1;
763 	}
764 	/*
765 	 * sorry, slow section here - but it's not time critical anyway
766 	 */
767 
768 	/*
769 	 * calculate days since 1970 (watching leap years)
770 	 */
771 	t = julian0( clock_time->year ) - julian0( 1970 );
772 
773   				/* month */
774 	if (clock_time->month <= 0 || clock_time->month > 12)
775 	{
776 		SETRTC(CVT_FAIL|CVT_BADDATE);
777 		return -1;		/* bad month */
778 	}
779 				/* adjust current leap year */
780 #if 0
781 	if (clock_time->month < 3 && days_per_year(clock_time->year) == 366)
782 	    t--;
783 #endif
784 
785 	/*
786 	 * collect days from months excluding the current one
787 	 */
788 	for (i = 1; i < clock_time->month; i++)
789 	{
790 		t += days_of_month[i];
791 	}
792 				/* day */
793 	if (clock_time->day < 1 || ((clock_time->month == 2 && days_per_year(clock_time->year) == 366) ?
794 			       clock_time->day > 29 : clock_time->day > days_of_month[clock_time->month]))
795 	{
796 		SETRTC(CVT_FAIL|CVT_BADDATE);
797 		return -1;		/* bad day */
798 	}
799 
800 	/*
801 	 * collect days from date excluding the current one
802 	 */
803 	t += clock_time->day - 1;
804 
805 				/* hour */
806 	if (clock_time->hour < 0 || clock_time->hour >= 24)
807 	{
808 		SETRTC(CVT_FAIL|CVT_BADTIME);
809 		return -1;		/* bad hour */
810 	}
811 
812 	/*
813 	 * calculate hours from 1. 1. 1970
814 	 */
815 	t = TIMES24(t) + clock_time->hour;
816 
817   				/* min */
818 	if (clock_time->minute < 0 || clock_time->minute > 59)
819 	{
820 		SETRTC(CVT_FAIL|CVT_BADTIME);
821 		return -1;		/* bad min */
822 	}
823 
824 	/*
825 	 * calculate minutes from 1. 1. 1970
826 	 */
827 	t = TIMES60(t) + clock_time->minute;
828 				/* sec */
829 
830 	/*
831 	 * calculate UTC in minutes
832 	 */
833 	t += clock_time->utcoffset;
834 
835 	if (clock_time->second < 0 || clock_time->second > 60)	/* allow for LEAPs */
836 	{
837 		SETRTC(CVT_FAIL|CVT_BADTIME);
838 		return -1;		/* bad sec */
839 	}
840 
841 	/*
842 	 * calculate UTC in seconds - phew !
843 	 */
844 	t  = TIMES60(t) + clock_time->second;
845 				/* done */
846 	return t;
847 }
848 
849 /*-----------------------------------------------------------------------
850  * cheap half baked 1/0 decision - for interactive operation only
851  */
852 static char
853 type(
854      unsigned int c
855      )
856 {
857 	c ^= 0xFF;
858 	return (c > 0xF);
859 }
860 
861 /*-----------------------------------------------------------------------
862  * week day representation
863  */
864 static const char *wday[8] =
865 {
866 	"??",
867 	"Mo",
868 	"Tu",
869 	"We",
870 	"Th",
871 	"Fr",
872 	"Sa",
873 	"Su"
874 };
875 
876 /*-----------------------------------------------------------------------
877  * generate a string representation for a timeval
878  */
879 static char *
880 pr_timeval(
881 	   struct timeval *val
882 	   )
883 {
884 	static char buf[20];
885 
886 	if (val->tv_sec == 0)
887 	    sprintf(buf, "%c0.%06ld", (val->tv_usec < 0) ? '-' : '+', (long int)l_abs(val->tv_usec));
888 	else
889 	    sprintf(buf, "%ld.%06ld", (long int)val->tv_sec, (long int)l_abs(val->tv_usec));
890 	return buf;
891 }
892 
893 /*-----------------------------------------------------------------------
894  * correct the current time by an offset by setting the time rigorously
895  */
896 static void
897 set_time(
898 	 struct timeval *offset
899 	 )
900 {
901 	struct timeval the_time;
902 
903 	if (no_set)
904 	    return;
905 
906 	LPRINTF("set_time: %s ", pr_timeval(offset));
907 	syslog(LOG_NOTICE, "setting time (offset %s)", pr_timeval(offset));
908 
909 	if (gettimeofday(&the_time, 0L) == -1)
910 	{
911 		perror("gettimeofday()");
912 	}
913 	else
914 	{
915 		timeradd(&the_time, offset);
916 		if (settimeofday(&the_time, 0L) == -1)
917 		{
918 			perror("settimeofday()");
919 		}
920 	}
921 }
922 
923 /*-----------------------------------------------------------------------
924  * slew the time by a given offset
925  */
926 static void
927 adj_time(
928 	 long offset
929 	 )
930 {
931 	struct timeval time_offset;
932 
933 	if (no_set)
934 	    return;
935 
936 	time_offset.tv_sec  = offset / 1000000;
937 	time_offset.tv_usec = offset % 1000000;
938 
939 	LPRINTF("adj_time: %ld us ", (long int)offset);
940 	if (adjtime(&time_offset, 0L) == -1)
941 	    perror("adjtime()");
942 }
943 
944 /*-----------------------------------------------------------------------
945  * read in a possibly previously written drift value
946  */
947 static void
948 read_drift(
949 	   const char *drift_file
950 	   )
951 {
952 	FILE *df;
953 
954 	df = fopen(drift_file, "r");
955 	if (df != NULL)
956 	{
957 		int idrift = 0, fdrift = 0;
958 
959 		fscanf(df, "%4d.%03d", &idrift, &fdrift);
960 		fclose(df);
961 		LPRINTF("read_drift: %d.%03d ppm ", idrift, fdrift);
962 
963 		accum_drift = idrift << USECSCALE;
964 		fdrift     = (fdrift << USECSCALE) / 1000;
965 		accum_drift += fdrift & (1<<USECSCALE);
966 		LPRINTF("read_drift: drift_comp %ld ", (long int)accum_drift);
967 	}
968 }
969 
970 /*-----------------------------------------------------------------------
971  * write out the current drift value
972  */
973 static void
974 update_drift(
975 	     const char *drift_file,
976 	     long offset,
977 	     time_t reftime
978 	     )
979 {
980 	FILE *df;
981 
982 	df = fopen(drift_file, "w");
983 	if (df != NULL)
984 	{
985 		int idrift = R_SHIFT(accum_drift, USECSCALE);
986 		int fdrift = accum_drift & ((1<<USECSCALE)-1);
987 
988 		LPRINTF("update_drift: drift_comp %ld ", (long int)accum_drift);
989 		fdrift = (fdrift * 1000) / (1<<USECSCALE);
990 		fprintf(df, "%4d.%03d %c%ld.%06ld %.24s\n", idrift, fdrift,
991 			(offset < 0) ? '-' : '+', (long int)(l_abs(offset) / 1000000),
992 			(long int)(l_abs(offset) % 1000000), asctime(localtime(&reftime)));
993 		fclose(df);
994 		LPRINTF("update_drift: %d.%03d ppm ", idrift, fdrift);
995 	}
996 }
997 
998 /*-----------------------------------------------------------------------
999  * process adjustments derived from the DCF77 observation
1000  * (controls clock PLL)
1001  */
1002 static void
1003 adjust_clock(
1004 	     struct timeval *offset,
1005 	     const char *drift_file,
1006 	     time_t reftime
1007 	     )
1008 {
1009 	struct timeval toffset;
1010 	register long usecoffset;
1011 	int tmp;
1012 
1013 	if (no_set)
1014 	    return;
1015 
1016 	if (skip_adjust)
1017 	{
1018 		skip_adjust = 0;
1019 		return;
1020 	}
1021 
1022 	toffset = *offset;
1023 	toffset.tv_sec  = l_abs(toffset.tv_sec);
1024 	toffset.tv_usec = l_abs(toffset.tv_usec);
1025 	if (timercmp(&toffset, &max_adj_offset, >))
1026 	{
1027 		/*
1028 		 * hopeless - set the clock - and clear the timing
1029 		 */
1030 		set_time(offset);
1031 		clock_adjust = 0;
1032 		skip_adjust  = 1;
1033 		return;
1034 	}
1035 
1036 	usecoffset   = offset->tv_sec * 1000000 + offset->tv_usec;
1037 
1038 	clock_adjust = R_SHIFT(usecoffset, TIMECONSTANT);	/* adjustment to make for next period */
1039 
1040 	tmp = 0;
1041 	while (adjustments > (1 << tmp))
1042 	    tmp++;
1043 	adjustments = 0;
1044 	if (tmp > FREQ_WEIGHT)
1045 	    tmp = FREQ_WEIGHT;
1046 
1047 	accum_drift  += R_SHIFT(usecoffset << USECSCALE, TIMECONSTANT+TIMECONSTANT+FREQ_WEIGHT-tmp);
1048 
1049 	if (accum_drift > MAX_DRIFT)		/* clamp into interval */
1050 	    accum_drift = MAX_DRIFT;
1051 	else
1052 	    if (accum_drift < -MAX_DRIFT)
1053 		accum_drift = -MAX_DRIFT;
1054 
1055 	update_drift(drift_file, usecoffset, reftime);
1056 	LPRINTF("clock_adjust: %s, clock_adjust %ld, drift_comp %ld(%ld) ",
1057 		pr_timeval(offset),(long int) R_SHIFT(clock_adjust, USECSCALE),
1058 		(long int)R_SHIFT(accum_drift, USECSCALE), (long int)accum_drift);
1059 }
1060 
1061 /*-----------------------------------------------------------------------
1062  * adjust the clock by a small mount to simulate frequency correction
1063  */
1064 static void
1065 periodic_adjust(
1066 		void
1067 		)
1068 {
1069 	register long adjustment;
1070 
1071 	adjustments++;
1072 
1073 	adjustment = R_SHIFT(clock_adjust, PHASE_WEIGHT);
1074 
1075 	clock_adjust -= adjustment;
1076 
1077 	adjustment += R_SHIFT(accum_drift, USECSCALE+ADJINTERVAL);
1078 
1079 	adj_time(adjustment);
1080 }
1081 
1082 /*-----------------------------------------------------------------------
1083  * control synchronisation status (warnings) and do periodic adjusts
1084  * (frequency control simulation)
1085  */
1086 static void
1087 tick(
1088      int signum
1089      )
1090 {
1091 	static unsigned long last_notice = 0;
1092 
1093 #if !defined(HAVE_SIGACTION) && !defined(HAVE_SIGVEC)
1094 	(void)signal(SIGALRM, tick);
1095 #endif
1096 
1097 	periodic_adjust();
1098 
1099 	ticks += 1<<ADJINTERVAL;
1100 
1101 	if ((ticks - last_sync) > MAX_UNSYNC)
1102 	{
1103 		/*
1104 		 * not getting time for a while
1105 		 */
1106 		if (sync_state == SYNC)
1107 		{
1108 			/*
1109 			 * completely lost information
1110 			 */
1111 			sync_state = NO_SYNC;
1112 			syslog(LOG_INFO, "DCF77 reception lost (timeout)");
1113 			last_notice = ticks;
1114 		}
1115 		else
1116 		    /*
1117 		     * in NO_SYNC state - look whether its time to speak up again
1118 		     */
1119 		    if ((ticks - last_notice) > NOTICE_INTERVAL)
1120 		    {
1121 			    syslog(LOG_NOTICE, "still not synchronized to DCF77 - check receiver/signal");
1122 			    last_notice = ticks;
1123 		    }
1124 	}
1125 
1126 #ifndef ITIMER_REAL
1127 	(void) alarm(1<<ADJINTERVAL);
1128 #endif
1129 }
1130 
1131 /*-----------------------------------------------------------------------
1132  * break association from terminal to avoid catching terminal
1133  * or process group related signals (-> daemon operation)
1134  */
1135 static void
1136 detach(
1137        void
1138        )
1139 {
1140 #   ifdef HAVE_DAEMON
1141 	daemon(0, 0);
1142 #   else /* not HAVE_DAEMON */
1143 	if (fork())
1144 	    exit(0);
1145 
1146 	{
1147 		u_long s;
1148 		int max_fd;
1149 
1150 #if defined(HAVE_SYSCONF) && defined(_SC_OPEN_MAX)
1151 		max_fd = sysconf(_SC_OPEN_MAX);
1152 #else /* HAVE_SYSCONF && _SC_OPEN_MAX */
1153 		max_fd = getdtablesize();
1154 #endif /* HAVE_SYSCONF && _SC_OPEN_MAX */
1155 		for (s = 0; s < max_fd; s++)
1156 		    (void) close((int)s);
1157 		(void) open("/", 0);
1158 		(void) dup2(0, 1);
1159 		(void) dup2(0, 2);
1160 #ifdef SYS_DOMAINOS
1161 		{
1162 			uid_$t puid;
1163 			status_$t st;
1164 
1165 			proc2_$who_am_i(&puid);
1166 			proc2_$make_server(&puid, &st);
1167 		}
1168 #endif /* SYS_DOMAINOS */
1169 #if defined(HAVE_SETPGID) || defined(HAVE_SETSID)
1170 # ifdef HAVE_SETSID
1171 		if (setsid() == (pid_t)-1)
1172 		    syslog(LOG_ERR, "dcfd: setsid(): %m");
1173 # else
1174 		if (setpgid(0, 0) == -1)
1175 		    syslog(LOG_ERR, "dcfd: setpgid(): %m");
1176 # endif
1177 #else /* HAVE_SETPGID || HAVE_SETSID */
1178 		{
1179 			int fid;
1180 
1181 			fid = open("/dev/tty", 2);
1182 			if (fid >= 0)
1183 			{
1184 				(void) ioctl(fid, (u_long) TIOCNOTTY, (char *) 0);
1185 				(void) close(fid);
1186 			}
1187 # ifdef HAVE_SETPGRP_0
1188 			(void) setpgrp();
1189 # else /* HAVE_SETPGRP_0 */
1190 			(void) setpgrp(0, getpid());
1191 # endif /* HAVE_SETPGRP_0 */
1192 		}
1193 #endif /* HAVE_SETPGID || HAVE_SETSID */
1194 	}
1195 #endif /* not HAVE_DAEMON */
1196 }
1197 
1198 /*-----------------------------------------------------------------------
1199  * list possible arguments and options
1200  */
1201 static void
1202 usage(
1203       char *program
1204       )
1205 {
1206   fprintf(stderr, "usage: %s [-n] [-f] [-l] [-t] [-i] [-o] [-d <drift_file>] [-D <input delay>] <device>\n", program);
1207 	fprintf(stderr, "\t-n              do not change time\n");
1208 	fprintf(stderr, "\t-i              interactive\n");
1209 	fprintf(stderr, "\t-t              trace (print all datagrams)\n");
1210 	fprintf(stderr, "\t-f              print all databits (includes PTB private data)\n");
1211 	fprintf(stderr, "\t-l              print loop filter debug information\n");
1212 	fprintf(stderr, "\t-o              print offet average for current minute\n");
1213 	fprintf(stderr, "\t-Y              make internal Y2K checks then exit\n");	/* Y2KFixes */
1214 	fprintf(stderr, "\t-d <drift_file> specify alternate drift file\n");
1215 	fprintf(stderr, "\t-D <input delay>specify delay from input edge to processing in micro seconds\n");
1216 }
1217 
1218 /*-----------------------------------------------------------------------
1219  * check_y2k() - internal check of Y2K logic
1220  *	(a lot of this logic lifted from ../ntpd/check_y2k.c)
1221  */
1222 static int
1223 check_y2k( void )
1224 {
1225     int  year;			/* current working year */
1226     int  year0 = 1900;		/* sarting year for NTP time */
1227     int  yearend;		/* ending year we test for NTP time.
1228 				    * 32-bit systems: through 2036, the
1229 				      **year in which NTP time overflows.
1230 				    * 64-bit systems: a reasonable upper
1231 				      **limit (well, maybe somewhat beyond
1232 				      **reasonable, but well before the
1233 				      **max time, by which time the earth
1234 				      **will be dead.) */
1235     time_t Time;
1236     struct tm LocalTime;
1237 
1238     int Fatals, Warnings;
1239 #define Error(year) if ( (year)>=2036 && LocalTime.tm_year < 110 ) \
1240 	Warnings++; else Fatals++
1241 
1242     Fatals = Warnings = 0;
1243 
1244     Time = time( (time_t *)NULL );
1245     LocalTime = *localtime( &Time );
1246 
1247     year = ( sizeof( u_long ) > 4 ) 	/* save max span using year as temp */
1248 		? ( 400 * 3 ) 		/* three greater gregorian cycles */
1249 		: ((int)(0x7FFFFFFF / 365.242 / 24/60/60)* 2 ); /*32-bit limit*/
1250 			/* NOTE: will automacially expand test years on
1251 			 * 64 bit machines.... this may cause some of the
1252 			 * existing ntp logic to fail for years beyond
1253 			 * 2036 (the current 32-bit limit). If all checks
1254 			 * fail ONLY beyond year 2036 you may ignore such
1255 			 * errors, at least for a decade or so. */
1256     yearend = year0 + year;
1257 
1258     year = 1900+YEAR_PIVOT;
1259     printf( "  starting year %04d\n", (int) year );
1260     printf( "  ending year   %04d\n", (int) yearend );
1261 
1262     for ( ; year < yearend; year++ )
1263     {
1264 	clocktime_t  ct;
1265 	time_t	     Observed;
1266 	time_t	     Expected;
1267 	unsigned     Flag;
1268 	unsigned long t;
1269 
1270 	ct.day = 1;
1271 	ct.month = 1;
1272 	ct.year = year;
1273 	ct.hour = ct.minute = ct.second = ct.usecond = 0;
1274 	ct.utcoffset = 0;
1275 	ct.flags = 0;
1276 
1277 	Flag = 0;
1278  	Observed = dcf_to_unixtime( &ct, &Flag );
1279 		/* seems to be a clone of parse_to_unixtime() with
1280 		 * *a minor difference to arg2 type */
1281 	if ( ct.year != year )
1282 	{
1283 	    fprintf( stdout,
1284 	       "%04d: dcf_to_unixtime(,%d) CORRUPTED ct.year: was %d\n",
1285 	       (int)year, (int)Flag, (int)ct.year );
1286 	    Error(year);
1287 	    break;
1288 	}
1289 	t = julian0(year) - julian0(1970);	/* Julian day from 1970 */
1290 	Expected = t * 24 * 60 * 60;
1291 	if ( Observed != Expected  ||  Flag )
1292 	{   /* time difference */
1293 	    fprintf( stdout,
1294 	       "%04d: dcf_to_unixtime(,%d) FAILURE: was=%lu s/b=%lu  (%ld)\n",
1295 	       year, (int)Flag,
1296 	       (unsigned long)Observed, (unsigned long)Expected,
1297 	       ((long)Observed - (long)Expected) );
1298 	    Error(year);
1299 	    break;
1300 	}
1301 
1302 	if ( year >= YEAR_PIVOT+1900 )
1303 	{
1304 	    /* check year % 100 code we put into dcf_to_unixtime() */
1305 	    ct.year = year % 100;
1306 	    Flag = 0;
1307 
1308 	    Observed = dcf_to_unixtime( &ct, &Flag );
1309 
1310 	    if ( Observed != Expected  ||  Flag )
1311 	    {   /* time difference */
1312 		fprintf( stdout,
1313 "%04d: dcf_to_unixtime(%d,%d) FAILURE: was=%lu s/b=%lu  (%ld)\n",
1314 		   year, (int)ct.year, (int)Flag,
1315 		   (unsigned long)Observed, (unsigned long)Expected,
1316 		   ((long)Observed - (long)Expected) );
1317 		Error(year);
1318 		break;
1319 	    }
1320 
1321 	    /* check year - 1900 code we put into dcf_to_unixtime() */
1322 	    ct.year = year - 1900;
1323 	    Flag = 0;
1324 
1325 	    Observed = dcf_to_unixtime( &ct, &Flag );
1326 
1327 	    if ( Observed != Expected  ||  Flag ) {   /* time difference */
1328 		    fprintf( stdout,
1329 			     "%04d: dcf_to_unixtime(%d,%d) FAILURE: was=%lu s/b=%lu  (%ld)\n",
1330 			     year, (int)ct.year, (int)Flag,
1331 			     (unsigned long)Observed, (unsigned long)Expected,
1332 			     ((long)Observed - (long)Expected) );
1333 		    Error(year);
1334 		break;
1335 	    }
1336 
1337 
1338 	}
1339     }
1340 
1341     return ( Fatals );
1342 }
1343 
1344 /*--------------------------------------------------
1345  * rawdcf_init - set up modem lines for RAWDCF receivers
1346  */
1347 #if defined(TIOCMSET) && (defined(TIOCM_DTR) || defined(CIOCM_DTR))
1348 static void
1349 rawdcf_init(
1350 	int fd
1351 	)
1352 {
1353 	/*
1354 	 * You can use the RS232 to supply the power for a DCF77 receiver.
1355 	 * Here a voltage between the DTR and the RTS line is used. Unfortunately
1356 	 * the name has changed from CIOCM_DTR to TIOCM_DTR recently.
1357 	 */
1358 
1359 #ifdef TIOCM_DTR
1360 	int sl232 = TIOCM_DTR;	/* turn on DTR for power supply */
1361 #else
1362 	int sl232 = CIOCM_DTR;	/* turn on DTR for power supply */
1363 #endif
1364 
1365 	if (ioctl(fd, TIOCMSET, (caddr_t)&sl232) == -1)
1366 	{
1367 		syslog(LOG_NOTICE, "rawdcf_init: WARNING: ioctl(fd, TIOCMSET, [C|T]IOCM_DTR): %m");
1368 	}
1369 }
1370 #else
1371 static void
1372 rawdcf_init(
1373 	    int fd
1374 	)
1375 {
1376 	syslog(LOG_NOTICE, "rawdcf_init: WARNING: OS interface incapable of setting DTR to power DCF modules");
1377 }
1378 #endif  /* DTR initialisation type */
1379 
1380 /*-----------------------------------------------------------------------
1381  * main loop - argument interpreter / setup / main loop
1382  */
1383 int
1384 main(
1385      int argc,
1386      char **argv
1387      )
1388 {
1389 	unsigned char c;
1390 	char **a = argv;
1391 	int  ac = argc;
1392 	char *file = NULL;
1393 	const char *drift_file = "/etc/dcfd.drift";
1394 	int fd;
1395 	int offset = 15;
1396 	int offsets = 0;
1397 	int delay = DEFAULT_DELAY;	/* average delay from input edge to time stamping */
1398 	int trace = 0;
1399 	int errs = 0;
1400 
1401 	/*
1402 	 * process arguments
1403 	 */
1404 	while (--ac)
1405 	{
1406 		char *arg = *++a;
1407 		if (*arg == '-')
1408 		    while ((c = *++arg))
1409 			switch (c)
1410 			{
1411 			    case 't':
1412 				trace = 1;
1413 				interactive = 1;
1414 				break;
1415 
1416 			    case 'f':
1417 				offset = 0;
1418 				interactive = 1;
1419 				break;
1420 
1421 			    case 'l':
1422 				loop_filter_debug = 1;
1423 				offsets = 1;
1424 				interactive = 1;
1425 				break;
1426 
1427 			    case 'n':
1428 				no_set = 1;
1429 				break;
1430 
1431 			    case 'o':
1432 				offsets = 1;
1433 				interactive = 1;
1434 				break;
1435 
1436 			    case 'i':
1437 				interactive = 1;
1438 				break;
1439 
1440 			    case 'D':
1441 				if (ac > 1)
1442 				{
1443 					delay = atoi(*++a);
1444 					ac--;
1445 				}
1446 				else
1447 				{
1448 					fprintf(stderr, "%s: -D requires integer argument\n", argv[0]);
1449 					errs=1;
1450 				}
1451 				break;
1452 
1453 			    case 'd':
1454 				if (ac > 1)
1455 				{
1456 					drift_file = *++a;
1457 					ac--;
1458 				}
1459 				else
1460 				{
1461 					fprintf(stderr, "%s: -d requires file name argument\n", argv[0]);
1462 					errs=1;
1463 				}
1464 				break;
1465 
1466 			    case 'Y':
1467 				errs=check_y2k();
1468 				exit( errs ? 1 : 0 );
1469 
1470 			    default:
1471 				fprintf(stderr, "%s: unknown option -%c\n", argv[0], c);
1472 				errs=1;
1473 				break;
1474 			}
1475 		else
1476 		    if (file == NULL)
1477 			file = arg;
1478 		    else
1479 		    {
1480 			    fprintf(stderr, "%s: device specified twice\n", argv[0]);
1481 			    errs=1;
1482 		    }
1483 	}
1484 
1485 	if (errs)
1486 	{
1487 		usage(argv[0]);
1488 		exit(1);
1489 	}
1490 	else
1491 	    if (file == NULL)
1492 	    {
1493 		    fprintf(stderr, "%s: device not specified\n", argv[0]);
1494 		    usage(argv[0]);
1495 		    exit(1);
1496 	    }
1497 
1498 	errs = LINES+1;
1499 
1500 	/*
1501 	 * get access to DCF77 tty port
1502 	 */
1503 	fd = open(file, O_RDONLY);
1504 	if (fd == -1)
1505 	{
1506 		perror(file);
1507 		exit(1);
1508 	}
1509 	else
1510 	{
1511 		int i, rrc;
1512 		struct timeval t, tt, tlast;
1513 		struct timeval timeout;
1514 		struct timeval phase;
1515 		struct timeval time_offset;
1516 		char pbuf[61];		/* printable version */
1517 		char buf[61];		/* raw data */
1518 		clocktime_t clock_time;	/* wall clock time */
1519 		time_t utc_time = 0;
1520 		time_t last_utc_time = 0;
1521 		long usecerror = 0;
1522 		long lasterror = 0;
1523 #if defined(HAVE_TERMIOS_H) || defined(STREAM)
1524 		struct termios term;
1525 #else  /* not HAVE_TERMIOS_H || STREAM */
1526 # if defined(HAVE_TERMIO_H) || defined(HAVE_SYSV_TTYS)
1527 		struct termio term;
1528 # endif/* HAVE_TERMIO_H || HAVE_SYSV_TTYS */
1529 #endif /* not HAVE_TERMIOS_H || STREAM */
1530 		unsigned int rtc = CVT_NONE;
1531 
1532 		rawdcf_init(fd);
1533 
1534 		timeout.tv_sec  = 1;
1535 		timeout.tv_usec = 500000;
1536 
1537 		phase.tv_sec    = 0;
1538 		phase.tv_usec   = delay;
1539 
1540 		/*
1541 		 * setup TTY (50 Baud, Read, 8Bit, No Hangup, 1 character IO)
1542 		 */
1543 		if (TTY_GETATTR(fd,  &term) == -1)
1544 		{
1545 			perror("tcgetattr");
1546 			exit(1);
1547 		}
1548 
1549 		memset(term.c_cc, 0, sizeof(term.c_cc));
1550 		term.c_cc[VMIN] = 1;
1551 #ifdef NO_PARENB_IGNPAR
1552 		term.c_cflag = B50|CS8|CREAD|CLOCAL;
1553 #else
1554 		term.c_cflag = B50|CS8|CREAD|CLOCAL|PARENB;
1555 #endif
1556 		term.c_iflag = IGNPAR;
1557 		term.c_oflag = 0;
1558 		term.c_lflag = 0;
1559 
1560 		if (TTY_SETATTR(fd, &term) == -1)
1561 		{
1562 			perror("tcsetattr");
1563 			exit(1);
1564 		}
1565 
1566 		/*
1567 		 * lose terminal if in daemon operation
1568 		 */
1569 		if (!interactive)
1570 		    detach();
1571 
1572 		/*
1573 		 * get syslog() initialized
1574 		 */
1575 #ifdef LOG_DAEMON
1576 		openlog("dcfd", LOG_PID, LOG_DAEMON);
1577 #else
1578 		openlog("dcfd", LOG_PID);
1579 #endif
1580 
1581 		/*
1582 		 * setup periodic operations (state control / frequency control)
1583 		 */
1584 #ifdef HAVE_SIGVEC
1585 		{
1586 			struct sigvec vec;
1587 
1588 			vec.sv_handler   = tick;
1589 			vec.sv_mask      = 0;
1590 			vec.sv_flags     = 0;
1591 
1592 			if (sigvec(SIGALRM, &vec, (struct sigvec *)0) == -1)
1593 			{
1594 				syslog(LOG_ERR, "sigvec(SIGALRM): %m");
1595 				exit(1);
1596 			}
1597 		}
1598 #else
1599 #ifdef HAVE_SIGACTION
1600 		{
1601 			struct sigaction act;
1602 
1603 			act.sa_handler   = tick;
1604 # ifdef HAVE_SA_SIGACTION_IN_STRUCT_SIGACTION
1605 			act.sa_sigaction = (void (*) P((int, siginfo_t *, void *)))0;
1606 # endif /* HAVE_SA_SIGACTION_IN_STRUCT_SIGACTION */
1607 			sigemptyset(&act.sa_mask);
1608 			act.sa_flags     = 0;
1609 
1610 			if (sigaction(SIGALRM, &act, (struct sigaction *)0) == -1)
1611 			{
1612 				syslog(LOG_ERR, "sigaction(SIGALRM): %m");
1613 				exit(1);
1614 			}
1615 		}
1616 #else
1617 		(void) signal(SIGALRM, tick);
1618 #endif
1619 #endif
1620 
1621 #ifdef ITIMER_REAL
1622 		{
1623 			struct itimerval it;
1624 
1625 			it.it_interval.tv_sec  = 1<<ADJINTERVAL;
1626 			it.it_interval.tv_usec = 0;
1627 			it.it_value.tv_sec     = 1<<ADJINTERVAL;
1628 			it.it_value.tv_usec    = 0;
1629 
1630 			if (setitimer(ITIMER_REAL, &it, (struct itimerval *)0) == -1)
1631 			{
1632 				syslog(LOG_ERR, "setitimer: %m");
1633 				exit(1);
1634 			}
1635 		}
1636 #else
1637 		(void) alarm(1<<ADJINTERVAL);
1638 #endif
1639 
1640 		PRINTF("  DCF77 monitor - Copyright (C) 1993-1998 by Frank Kardel\n\n");
1641 
1642 		pbuf[60] = '\0';
1643 		for ( i = 0; i < 60; i++)
1644 		    pbuf[i] = '.';
1645 
1646 		read_drift(drift_file);
1647 
1648 		/*
1649 		 * what time is it now (for interval measurement)
1650 		 */
1651 		gettimeofday(&tlast, 0L);
1652 		i = 0;
1653 		/*
1654 		 * loop until input trouble ...
1655 		 */
1656 		do
1657 		{
1658 			/*
1659 			 * get an impulse
1660 			 */
1661 			while ((rrc = read(fd, &c, 1)) == 1)
1662 			{
1663 				gettimeofday(&t, 0L);
1664 				tt = t;
1665 				timersub(&t, &tlast);
1666 
1667 				if (errs > LINES)
1668 				{
1669 					PRINTF("  %s", &"PTB private....RADMLSMin....PHour..PMDay..DayMonthYear....P\n"[offset]);
1670 					PRINTF("  %s", &"---------------RADMLS1248124P124812P1248121241248112481248P\n"[offset]);
1671 					errs = 0;
1672 				}
1673 
1674 				/*
1675 				 * timeout -> possible minute mark -> interpretation
1676 				 */
1677 				if (timercmp(&t, &timeout, >))
1678 				{
1679 					PRINTF("%c %.*s ", pat[i % (sizeof(pat)-1)], 59 - offset, &pbuf[offset]);
1680 
1681 					if ((rtc = cvt_rawdcf((unsigned char *)buf, i, &clock_time)) != CVT_OK)
1682 					{
1683 						/*
1684 						 * this data was bad - well - forget synchronisation for now
1685 						 */
1686 						PRINTF("\n");
1687 						if (sync_state == SYNC)
1688 						{
1689 							sync_state = NO_SYNC;
1690 							syslog(LOG_INFO, "DCF77 reception lost (bad data)");
1691 						}
1692 						errs++;
1693 					}
1694 					else
1695 					    if (trace)
1696 					    {
1697 						    PRINTF("\r  %.*s ", 59 - offset, &buf[offset]);
1698 					    }
1699 
1700 
1701 					buf[0] = c;
1702 
1703 					/*
1704 					 * collect first character
1705 					 */
1706 					if (((c^0xFF)+1) & (c^0xFF))
1707 					    pbuf[0] = '?';
1708 					else
1709 					    pbuf[0] = type(c) ? '#' : '-';
1710 
1711 					for ( i = 1; i < 60; i++)
1712 					    pbuf[i] = '.';
1713 
1714 					i = 0;
1715 				}
1716 				else
1717 				{
1718 					/*
1719 					 * collect character
1720 					 */
1721 					buf[i] = c;
1722 
1723 					/*
1724 					 * initial guess (usually correct)
1725 					 */
1726 					if (((c^0xFF)+1) & (c^0xFF))
1727 					    pbuf[i] = '?';
1728 					else
1729 					    pbuf[i] = type(c) ? '#' : '-';
1730 
1731 					PRINTF("%c %.*s ", pat[i % (sizeof(pat)-1)], 59 - offset, &pbuf[offset]);
1732 				}
1733 
1734 				if (i == 0 && rtc == CVT_OK)
1735 				{
1736 					/*
1737 					 * we got a good time code here - try to convert it to
1738 					 * UTC
1739 					 */
1740 					if ((utc_time = dcf_to_unixtime(&clock_time, &rtc)) == -1)
1741 					{
1742 						PRINTF("*** BAD CONVERSION\n");
1743 					}
1744 
1745 					if (utc_time != (last_utc_time + 60))
1746 					{
1747 						/*
1748 						 * well, two successive sucessful telegrams are not 60 seconds
1749 						 * apart
1750 						 */
1751 						PRINTF("*** NO MINUTE INC\n");
1752 						if (sync_state == SYNC)
1753 						{
1754 							sync_state = NO_SYNC;
1755 							syslog(LOG_INFO, "DCF77 reception lost (data mismatch)");
1756 						}
1757 						errs++;
1758 						rtc = CVT_FAIL|CVT_BADTIME|CVT_BADDATE;
1759 					}
1760 					else
1761 					    usecerror = 0;
1762 
1763 					last_utc_time = utc_time;
1764 				}
1765 
1766 				if (rtc == CVT_OK)
1767 				{
1768 					if (i == 0)
1769 					{
1770 						/*
1771 						 * valid time code - determine offset and
1772 						 * note regained reception
1773 						 */
1774 						last_sync = ticks;
1775 						if (sync_state == NO_SYNC)
1776 						{
1777 							syslog(LOG_INFO, "receiving DCF77");
1778 						}
1779 						else
1780 						{
1781 							/*
1782 							 * we had at least one minute SYNC - thus
1783 							 * last error is valid
1784 							 */
1785 							time_offset.tv_sec  = lasterror / 1000000;
1786 							time_offset.tv_usec = lasterror % 1000000;
1787 							adjust_clock(&time_offset, drift_file, utc_time);
1788 						}
1789 						sync_state = SYNC;
1790 					}
1791 
1792 					time_offset.tv_sec  = utc_time + i;
1793 					time_offset.tv_usec = 0;
1794 
1795 					timeradd(&time_offset, &phase);
1796 
1797 					usecerror += (time_offset.tv_sec - tt.tv_sec) * 1000000 + time_offset.tv_usec
1798 						-tt.tv_usec;
1799 
1800 					/*
1801 					 * output interpreted DCF77 data
1802 					 */
1803 					PRINTF(offsets ? "%s, %2ld:%02ld:%02d, %ld.%02ld.%02ld, <%s%s%s%s> (%c%ld.%06lds)" :
1804 					       "%s, %2ld:%02ld:%02d, %ld.%02ld.%02ld, <%s%s%s%s>",
1805 					       wday[clock_time.wday],
1806 					       clock_time.hour, clock_time.minute, i, clock_time.day, clock_time.month,
1807 					       clock_time.year,
1808 					       (clock_time.flags & DCFB_ALTERNATE) ? "R" : "_",
1809 					       (clock_time.flags & DCFB_ANNOUNCE) ? "A" : "_",
1810 					       (clock_time.flags & DCFB_DST) ? "D" : "_",
1811 					       (clock_time.flags & DCFB_LEAP) ? "L" : "_",
1812 					       (lasterror < 0) ? '-' : '+', l_abs(lasterror) / 1000000, l_abs(lasterror) % 1000000
1813 					       );
1814 
1815 					if (trace && (i == 0))
1816 					{
1817 						PRINTF("\n");
1818 						errs++;
1819 					}
1820 					lasterror = usecerror / (i+1);
1821 				}
1822 				else
1823 				{
1824 					lasterror = 0; /* we cannot calculate phase errors on bad reception */
1825 				}
1826 
1827 				PRINTF("\r");
1828 
1829 				if (i < 60)
1830 				{
1831 					i++;
1832 				}
1833 
1834 				tlast = tt;
1835 
1836 				if (interactive)
1837 				    fflush(stdout);
1838 			}
1839 		} while ((rrc == -1) && (errno == EINTR));
1840 
1841 		/*
1842 		 * lost IO - sorry guys
1843 		 */
1844 		syslog(LOG_ERR, "TERMINATING - cannot read from device %s (%m)", file);
1845 
1846 		(void)close(fd);
1847 	}
1848 
1849 	closelog();
1850 
1851 	return 0;
1852 }
1853