freebsd-dev/usr.sbin/xntpd/parse/util/dcfd.c
Jordan K. Hubbard ee0afc78a8 Patches to make this work with FreeBSD with the DCF77 Boeder Receiver.
This is only useful to European users (esp. Germans) as DCF77 transmits
from Frankfurt.
Submitted by:	Vincenzo Capuano <VCAPUANO@VMPROFS.ESOC.ESA.DE>
1995-03-31 07:01:11 +00:00

1619 lines
38 KiB
C

/*
* /src/NTP/REPOSITORY/v3/parse/util/dcfd.c,v 3.18 1994/05/12 12:49:23 kardel Exp
*
* dcfd.c,v 3.18 1994/05/12 12:49:23 kardel Exp
*
* Ported to FreeBSD 2.0 1995/03/20 by Vincenzo Capuano
*
* DCF77 100/200ms pulse synchronisation daemon program (via 50Baud serial line)
*
* Features:
* DCF77 decoding
* NTP loopfilter logic for local clock
* interactive display for debugging
*
* Lacks:
* Leap second handling (at that level you should switch to xntp3 - really!)
*
* Copyright (c) 1993,1994
* Frank Kardel, Friedrich-Alexander Universitaet Erlangen-Nuernberg
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* This program may not be sold or used for profit without prior
* written consent of the author.
*/
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/signal.h>
#include <sys/errno.h>
#include <syslog.h>
/*
* NTP compilation environment
*/
#ifdef USE_PROTOTYPES
#include "ntp_stdlib.h"
#include <signal.h>
#include <stdio.h>
#endif
#ifdef SYS_LINUX
#include "ntp_timex.h"
#endif
/*
* select which terminal handling to use (currently only SysV variants)
*/
#if defined(HAVE_TERMIOS) || defined(STREAM)
#include <termios.h>
#define TTY_GETATTR(_FD_, _ARG_) tcgetattr((_FD_), (_ARG_))
#define TTY_SETATTR(_FD_, _ARG_) tcsetattr((_FD_), TCSANOW, (_ARG_))
#endif
#if defined(HAVE_TERMIO) || defined(HAVE_SYSV_TTYS)
#include <termio.h>
#define TTY_GETATTR(_FD_, _ARG_) ioctl((_FD_), TCGETA, (_ARG_))
#define TTY_SETATTR(_FD_, _ARG_) ioctl((_FD_), TCSETAW, (_ARG_))
#endif
#ifndef TTY_GETATTR
MUST DEFINE ONE OF "HAVE_TERMIOS" or "HAVE_TERMIO"
#endif
#ifndef dysize
#define dysize(_x_) (((_x_) % 4) ? 365 : (((_x_) % 400) ? 365 : 366))
#endif
#define timernormalize(_a_) \
if ((_a_)->tv_usec >= 1000000) \
{ \
(_a_)->tv_sec += (_a_)->tv_usec / 1000000; \
(_a_)->tv_usec = (_a_)->tv_usec % 1000000; \
} \
if ((_a_)->tv_usec < 0) \
{ \
(_a_)->tv_sec -= 1 + -(_a_)->tv_usec / 1000000; \
(_a_)->tv_usec = 1000000 - (-(_a_)->tv_usec % 1000000); \
}
#define timeradd(_a_, _b_) \
(_a_)->tv_sec += (_b_)->tv_sec; \
(_a_)->tv_usec += (_b_)->tv_usec; \
timernormalize((_a_))
#define timersub(_a_, _b_) \
(_a_)->tv_sec -= (_b_)->tv_sec; \
(_a_)->tv_usec -= (_b_)->tv_usec; \
timernormalize((_a_))
/*
* debug macros
*/
#define PRINTF if (interactive) printf
#define LPRINTF if (interactive && loop_filter_debug) printf
#ifdef DEBUG
#define dprintf(_x_) PRINTF _x_
#else
#define dprintf(_x_)
#endif
extern int errno;
/*
* display received data (avoids also detaching from tty)
*/
static int interactive = 0;
/*
* display loopfilter (clock control) variables
*/
static int loop_filter_debug = 0;
/*
* do not set/adjust system time
*/
static int no_set = 0;
/*
* time that passes between start of DCF impulse and time stamping (fine
* adjustment) in microseconds (receiver/OS dependent)
*/
#define DEFAULT_DELAY 230000 /* rough estimate */
/*
* The two states we can be in - eithe we receive nothing
* usable or we have the correct time
*/
#define NO_SYNC 0x01
#define SYNC 0x02
static int sync_state = NO_SYNC;
static time_t last_sync;
static unsigned long ticks = 0;
static char pat[] = "-\\|/";
#define LINES (24-2) /* error lines after which the two headlines are repeated */
#define MAX_UNSYNC (10*60) /* allow synchronisation loss for 10 minutes */
#define NOTICE_INTERVAL (20*60) /* mention missing synchronisation every 20 minutes */
/*
* clock adjustment PLL - see NTP protocol spec (RFC1305) for details
*/
#define USECSCALE 10
#define TIMECONSTANT 2
#define ADJINTERVAL 0
#define FREQ_WEIGHT 18
#define PHASE_WEIGHT 7
#define MAX_DRIFT 0x3FFFFFFF
#define R_SHIFT(_X_, _Y_) (((_X_) < 0) ? -(-(_X_) >> (_Y_)) : ((_X_) >> (_Y_)))
static struct timeval max_adj_offset = { 0, 128000 };
static long clock_adjust = 0; /* current adjustment value (usec * 2^USECSCALE) */
static long drift_comp = 0; /* accumulated drift value (usec / ADJINTERVAL) */
static long adjustments = 0;
static char skip_adjust = 1; /* discard first adjustment (bad samples) */
/*
* DCF77 state flags
*/
#define DCFB_ANNOUNCE 0x0001 /* switch time zone warning (DST switch) */
#define DCFB_DST 0x0002 /* DST in effect */
#define DCFB_LEAP 0x0004 /* LEAP warning (1 hour prior to occurence) */
#define DCFB_ALTERNATE 0x0008 /* alternate antenna used */
struct clocktime /* clock time broken up from time code */
{
long wday; /* Day of week: 1: Monday - 7: Sunday */
long day;
long month;
long year;
long hour;
long minute;
long second;
long usecond;
long utcoffset; /* in minutes */
long flags; /* current clock status (DCF77 state flags) */
};
typedef struct clocktime clocktime_t;
/*
* (usually) quick constant multiplications
*/
#define TIMES10(_X_) (((_X_) << 3) + ((_X_) << 1)) /* *8 + *2 */
#define TIMES24(_X_) (((_X_) << 4) + ((_X_) << 3)) /* *16 + *8 */
#define TIMES60(_X_) ((((_X_) << 4) - (_X_)) << 2) /* *(16 - 1) *4 */
/*
* generic abs() function
*/
#define abs(_x_) (((_x_) < 0) ? -(_x_) : (_x_))
/*
* conversion related return/error codes
*/
#define CVT_MASK 0x0000000F /* conversion exit code */
#define CVT_NONE 0x00000001 /* format not applicable */
#define CVT_FAIL 0x00000002 /* conversion failed - error code returned */
#define CVT_OK 0x00000004 /* conversion succeeded */
#define CVT_BADFMT 0x00000010 /* general format error - (unparsable) */
#define CVT_BADDATE 0x00000020 /* invalid date */
#define CVT_BADTIME 0x00000040 /* invalid time */
/*
* DCF77 raw time code
*
* From "Zur Zeit", Physikalisch-Technische Bundesanstalt (PTB), Braunschweig
* und Berlin, Maerz 1989
*
* Timecode transmission:
* AM:
* time marks are send every second except for the second before the
* next minute mark
* time marks consist of a reduction of transmitter power to 25%
* of the nominal level
* the falling edge is the time indication (on time)
* time marks of a 100ms duration constitute a logical 0
* time marks of a 200ms duration constitute a logical 1
* FM:
* see the spec. (basically a (non-)inverted psuedo random phase shift)
*
* Encoding:
* Second Contents
* 0 - 10 AM: free, FM: 0
* 11 - 14 free
* 15 R - alternate antenna
* 16 A1 - expect zone change (1 hour before)
* 17 - 18 Z1,Z2 - time zone
* 0 0 illegal
* 0 1 MEZ (MET)
* 1 0 MESZ (MED, MET DST)
* 1 1 illegal
* 19 A2 - expect leap insertion/deletion (1 hour before)
* 20 S - start of time code (1)
* 21 - 24 M1 - BCD (lsb first) Minutes
* 25 - 27 M10 - BCD (lsb first) 10 Minutes
* 28 P1 - Minute Parity (even)
* 29 - 32 H1 - BCD (lsb first) Hours
* 33 - 34 H10 - BCD (lsb first) 10 Hours
* 35 P2 - Hour Parity (even)
* 36 - 39 D1 - BCD (lsb first) Days
* 40 - 41 D10 - BCD (lsb first) 10 Days
* 42 - 44 DW - BCD (lsb first) day of week (1: Monday -> 7: Sunday)
* 45 - 49 MO - BCD (lsb first) Month
* 50 MO0 - 10 Months
* 51 - 53 Y1 - BCD (lsb first) Years
* 54 - 57 Y10 - BCD (lsb first) 10 Years
* 58 P3 - Date Parity (even)
* 59 - usually missing (minute indication), except for leap insertion
*/
/*-----------------------------------------------------------------------
* conversion table to map DCF77 bit stream into data fields.
* Encoding:
* Each field of the DCF77 code is described with two adjacent entries in
* this table. The first entry specifies the offset into the DCF77 data stream
* while the length is given as the difference between the start index and
* the start index of the following field.
*/
static struct rawdcfcode
{
char offset; /* start bit */
} rawdcfcode[] =
{
{ 0 }, { 15 }, { 16 }, { 17 }, { 19 }, { 20 }, { 21 }, { 25 }, { 28 }, { 29 },
{ 33 }, { 35 }, { 36 }, { 40 }, { 42 }, { 45 }, { 49 }, { 50 }, { 54 }, { 58 }, { 59 }
};
/*-----------------------------------------------------------------------
* symbolic names for the fields of DCF77 describes in "rawdcfcode".
* see comment above for the structure of the DCF77 data
*/
#define DCF_M 0
#define DCF_R 1
#define DCF_A1 2
#define DCF_Z 3
#define DCF_A2 4
#define DCF_S 5
#define DCF_M1 6
#define DCF_M10 7
#define DCF_P1 8
#define DCF_H1 9
#define DCF_H10 10
#define DCF_P2 11
#define DCF_D1 12
#define DCF_D10 13
#define DCF_DW 14
#define DCF_MO 15
#define DCF_MO0 16
#define DCF_Y1 17
#define DCF_Y10 18
#define DCF_P3 19
/*-----------------------------------------------------------------------
* parity field table (same encoding as rawdcfcode)
* This table describes the sections of the DCF77 code that are
* parity protected
*/
static struct partab
{
char offset; /* start bit of parity field */
} partab[] =
{
{ 21 }, { 29 }, { 36 }, { 59 }
};
/*-----------------------------------------------------------------------
* offsets for parity field descriptions
*/
#define DCF_P_P1 0
#define DCF_P_P2 1
#define DCF_P_P3 2
/*-----------------------------------------------------------------------
* legal values for time zone information
*/
#define DCF_Z_MET 0x2
#define DCF_Z_MED 0x1
/*-----------------------------------------------------------------------
* symbolic representation if the DCF77 data stream
*/
static struct dcfparam
{
unsigned char onebits[60];
unsigned char zerobits[60];
} dcfparam =
{
"###############RADMLS1248124P124812P1248121241248112481248P", /* 'ONE' representation */
"--------------------s-------p------p----------------------p" /* 'ZERO' representation */
};
/*-----------------------------------------------------------------------
* extract a bitfield from DCF77 datastream
* All numeric field are LSB first.
* buf holds a pointer to a DCF77 data buffer in symbolic
* representation
* idx holds the index to the field description in rawdcfcode
*/
static unsigned long ext_bf(buf, idx)
register unsigned char *buf;
register int idx;
{
register unsigned long sum = 0;
register int i, first;
first = rawdcfcode[idx].offset;
for (i = rawdcfcode[idx+1].offset - 1; i >= first; i--)
{
sum <<= 1;
sum |= (buf[i] != dcfparam.zerobits[i]);
}
return sum;
}
/*-----------------------------------------------------------------------
* check even parity integrity for a bitfield
*
* buf holds a pointer to a DCF77 data buffer in symbolic
* representation
* idx holds the index to the field description in partab
*/
static unsigned pcheck(buf, idx)
register unsigned char *buf;
register int idx;
{
register int i,last;
register unsigned psum = 1;
last = partab[idx+1].offset;
for (i = partab[idx].offset; i < last; i++)
psum ^= (buf[i] != dcfparam.zerobits[i]);
return psum;
}
/*-----------------------------------------------------------------------
* convert a DCF77 data buffer into wall clock time + flags
*
* buffer holds a pointer to a DCF77 data buffer in symbolic
* representation
* size describes the length of DCF77 information in bits (represented
* as chars in symbolic notation
* clock points to a wall clock time description of the DCF77 data (result)
*/
static unsigned long convert_rawdcf(buffer, size, clock)
register unsigned char *buffer;
register int size;
register clocktime_t *clock;
{
if (size < 57)
{
PRINTF("%-30s", "*** INCOMPLETE");
return CVT_NONE;
}
/*
* check Start and Parity bits
*/
if ((ext_bf(buffer, DCF_S) == 1) &&
pcheck(buffer, DCF_P_P1) &&
pcheck(buffer, DCF_P_P2) &&
pcheck(buffer, DCF_P_P3))
{
/*
* buffer OK - extract all fields and build wall clock time from them
*/
clock->flags = 0;
clock->usecond= 0;
clock->second = 0;
clock->minute = ext_bf(buffer, DCF_M10);
clock->minute = TIMES10(clock->minute) + ext_bf(buffer, DCF_M1);
clock->hour = ext_bf(buffer, DCF_H10);
clock->hour = TIMES10(clock->hour) + ext_bf(buffer, DCF_H1);
clock->day = ext_bf(buffer, DCF_D10);
clock->day = TIMES10(clock->day) + ext_bf(buffer, DCF_D1);
clock->month = ext_bf(buffer, DCF_MO0);
clock->month = TIMES10(clock->month) + ext_bf(buffer, DCF_MO);
clock->year = ext_bf(buffer, DCF_Y10);
clock->year = TIMES10(clock->year) + ext_bf(buffer, DCF_Y1);
clock->wday = ext_bf(buffer, DCF_DW);
/*
* determine offset to UTC by examining the time zone
*/
switch (ext_bf(buffer, DCF_Z))
{
case DCF_Z_MET:
clock->utcoffset = -60;
break;
case DCF_Z_MED:
clock->flags |= DCFB_DST;
clock->utcoffset = -120;
break;
default:
PRINTF("%-30s", "*** BAD TIME ZONE");
return CVT_FAIL|CVT_BADFMT;
}
/*
* extract various warnings from DCF77
*/
if (ext_bf(buffer, DCF_A1))
clock->flags |= DCFB_ANNOUNCE;
if (ext_bf(buffer, DCF_A2))
clock->flags |= DCFB_LEAP;
if (ext_bf(buffer, DCF_R))
clock->flags |= DCFB_ALTERNATE;
return CVT_OK;
}
else
{
/*
* bad format - not for us
*/
PRINTF("%-30s", "*** BAD FORMAT (invalid/parity)");
return CVT_FAIL|CVT_BADFMT;
}
}
/*-----------------------------------------------------------------------
* raw dcf input routine - fix up 50 baud
* characters for 1/0 decision
*/
static unsigned long cvt_rawdcf(buffer, size, clock)
register unsigned char *buffer;
register int size;
register clocktime_t *clock;
{
register unsigned char *s = buffer;
register unsigned char *e = buffer + size;
register unsigned char *b = dcfparam.onebits;
register unsigned char *c = dcfparam.zerobits;
register unsigned rtc = CVT_NONE;
register unsigned int i, lowmax, highmax, cutoff, span;
#define BITS 9
unsigned char histbuf[BITS];
/*
* the input buffer contains characters with runs of consecutive
* bits set. These set bits are an indication of the DCF77 pulse
* length. We assume that we receive the pulse at 50 Baud. Thus
* a 100ms pulse would generate a 4 bit train (20ms per bit and
* start bit)
* a 200ms pulse would create all zeroes (and probably a frame error)
*
* The basic idea is that on corret reception we must have two
* maxima in the pulse length distribution histogram. (one for
* the zero representing pulses and one for the one representing
* pulses)
* There will always be ones in the datastream, thus we have to see
* two maxima.
* The best point to cut for a 1/0 decision is the minimum between those
* between the maxima. The following code tries to find this cutoff point.
*/
/*
* clear histogram buffer
*/
for (i = 0; i < BITS; i++)
{
histbuf[i] = 0;
}
cutoff = 0;
lowmax = 0;
/*
* convert sequences of set bits into bits counts updating
* the histogram alongway
*/
while (s < e)
{
register unsigned int ch = *s ^ 0xFF;
/*
* check integrity and update histogramm
*/
if (!((ch+1) & ch) || !*s)
{
/*
* character ok
*/
for (i = 0; ch; i++)
{
ch >>= 1;
}
*s = i;
histbuf[i]++;
cutoff += i;
lowmax++;
}
else
{
/*
* invalid character (no consecutive bit sequence)
*/
dprintf(("parse: cvt_rawdcf: character check for 0x%x@%d FAILED\n", *s, s - buffer));
*s = ~0;
rtc = CVT_FAIL|CVT_BADFMT;
}
s++;
}
/*
* first cutoff estimate (average bit count - must be between both
* maxima)
*/
if (lowmax)
{
cutoff /= lowmax;
}
else
{
cutoff = 4; /* doesn't really matter - it'll fail anyway, but gives error output */
}
dprintf(("parse: cvt_rawdcf: average bit count: %d\n", cutoff));
lowmax = 0; /* weighted sum */
highmax = 0; /* bitcount */
/*
* collect weighted sum of lower bits (left of initial guess)
*/
dprintf(("parse: cvt_rawdcf: histogram:"));
for (i = 0; i <= cutoff; i++)
{
lowmax += histbuf[i] * i;
highmax += histbuf[i];
dprintf((" %d", histbuf[i]));
}
dprintf((" <M>"));
/*
* round up
*/
lowmax += highmax / 2;
/*
* calculate lower bit maximum (weighted sum / bit count)
*
* avoid divide by zero
*/
if (highmax)
{
lowmax /= highmax;
}
else
{
lowmax = 0;
}
highmax = 0; /* weighted sum of upper bits counts */
cutoff = 0; /* bitcount */
/*
* collect weighted sum of lower bits (right of initial guess)
*/
for (; i < BITS; i++)
{
highmax+=histbuf[i] * i;
cutoff +=histbuf[i];
dprintf((" %d", histbuf[i]));
}
dprintf(("\n"));
/*
* determine upper maximum (weighted sum / bit count)
*/
if (cutoff)
{
highmax /= cutoff;
}
else
{
highmax = BITS-1;
}
/*
* following now holds:
* lowmax <= cutoff(initial guess) <= highmax
* best cutoff is the minimum nearest to higher bits
*/
/*
* find the minimum between lowmax and highmax (detecting
* possibly a minimum span)
*/
span = cutoff = lowmax;
for (i = lowmax; i <= highmax; i++)
{
if (histbuf[cutoff] > histbuf[i])
{
/*
* got a new minimum move beginning of minimum (cutoff) and
* end of minimum (span) there
*/
cutoff = span = i;
}
else
if (histbuf[cutoff] == histbuf[i])
{
/*
* minimum not better yet - but it spans more than
* one bit value - follow it
*/
span = i;
}
}
/*
* cutoff point for 1/0 decision is the middle of the minimum section
* in the histogram
*/
cutoff = (cutoff + span) / 2;
dprintf(("parse: cvt_rawdcf: lower maximum %d, higher maximum %d, cutoff %d\n", lowmax, highmax, cutoff));
/*
* convert the bit counts to symbolic 1/0 information for data conversion
*/
s = buffer;
while ((s < e) && *c && *b)
{
if (*s == (unsigned char)~0)
{
/*
* invalid character
*/
*s = '?';
}
else
{
/*
* symbolic 1/0 representation
*/
*s = (*s >= cutoff) ? *b : *c;
}
s++;
b++;
c++;
}
/*
* if everything went well so far return the result of the symbolic
* conversion routine else just the accumulated errors
*/
if (rtc != CVT_NONE)
{
PRINTF("%-30s", "*** BAD DATA");
}
return (rtc == CVT_NONE) ? convert_rawdcf(buffer, size, clock) : rtc;
}
/*-----------------------------------------------------------------------
* convert a wall clock time description of DCF77 to a Unix time (seconds
* since 1.1. 1970 UTC)
*/
time_t
dcf_to_unixtime(clock, cvtrtc)
register clocktime_t *clock;
register unsigned long *cvtrtc;
{
#define SETRTC(_X_) { if (cvtrtc) *cvtrtc = (_X_); }
static int days_of_month[] =
{
0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
register int i;
time_t t;
/*
* map 2 digit years to 19xx (DCF77 is a 20th century item)
*/
if (clock->year < 100)
clock->year += 1900;
/*
* assume that we convert timecode within the unix/UTC epoch -
* prolonges validity of 2 digit years
*/
if (clock->year < 1994)
clock->year += 100; /* XXX this will do it till <2094 */
/*
* must have been a really negative year code - drop it
*/
if (clock->year < 0)
{
SETRTC(CVT_FAIL|CVT_BADDATE);
return -1;
}
/*
* sorry, slow section here - but it's not time critical anyway
*/
/*
* calculate days since 1970 (watching leap years)
*/
t = (clock->year - 1970) * 365;
t += (clock->year >> 2) - (1970 >> 2);
t -= clock->year / 400 - 1970 / 400;
/* month */
if (clock->month <= 0 || clock->month > 12)
{
SETRTC(CVT_FAIL|CVT_BADDATE);
return -1; /* bad month */
}
/* adjust current leap year */
if (clock->month >= 3 && dysize(clock->year) == 366)
t++;
/*
* collect days from months excluding the current one
*/
for (i = 1; i < clock->month; i++)
{
t += days_of_month[i];
}
/* day */
if (clock->day < 1 || ((clock->month == 2 && dysize(clock->year) == 366) ?
clock->day > 29 : clock->day > days_of_month[clock->month]))
{
SETRTC(CVT_FAIL|CVT_BADDATE);
return -1; /* bad day */
}
/*
* collect days from date excluding the current one
*/
t += clock->day - 1;
/* hour */
if (clock->hour < 0 || clock->hour >= 24)
{
SETRTC(CVT_FAIL|CVT_BADTIME);
return -1; /* bad hour */
}
/*
* calculate hours from 1. 1. 1970
*/
t = TIMES24(t) + clock->hour;
/* min */
if (clock->minute < 0 || clock->minute > 59)
{
SETRTC(CVT_FAIL|CVT_BADTIME);
return -1; /* bad min */
}
/*
* calculate minutes from 1. 1. 1970
*/
t = TIMES60(t) + clock->minute;
/* sec */
/*
* calculate UTC in minutes
*/
t += clock->utcoffset;
if (clock->second < 0 || clock->second > 60) /* allow for LEAPs */
{
SETRTC(CVT_FAIL|CVT_BADTIME);
return -1; /* bad sec */
}
/*
* calculate UTC in seconds - phew !
*/
t = TIMES60(t) + clock->second;
/* done */
return t;
}
/*-----------------------------------------------------------------------
* cheap half baked 1/0 decision - for interactive operation only
*/
static char type(c)
unsigned char c;
{
c ^= 0xFF;
return (c > 0xF);
}
/*-----------------------------------------------------------------------
* week day representation
*/
static char *wday[8] =
{
"??",
"Mo",
"Tu",
"We",
"Th",
"Fr",
"Sa",
"Su"
};
/*-----------------------------------------------------------------------
* generate a string representation for a timeval
*/
static char * pr_timeval(val)
struct timeval *val;
{
static char buf[20];
if (val->tv_sec == 0)
sprintf(buf, "%c0.%06ld", (val->tv_usec < 0) ? '-' : '+', (long int)abs(val->tv_usec));
else
sprintf(buf, "%ld.%06ld", (long int)val->tv_sec, (long int)abs(val->tv_usec));
return buf;
}
/*-----------------------------------------------------------------------
* correct the current time by an offset by setting the time rigorously
*/
static void set_time(offset)
struct timeval *offset;
{
struct timeval the_time;
if (no_set)
return;
LPRINTF("set_time: %s ", pr_timeval(offset));
syslog(LOG_NOTICE, "setting time (offset %s)", pr_timeval(offset));
if (gettimeofday(&the_time, 0L) == -1)
{
perror("gettimeofday()");
}
else
{
timeradd(&the_time, offset);
if (settimeofday(&the_time, 0L) == -1)
{
perror("settimeofday()");
}
}
}
/*-----------------------------------------------------------------------
* slew the time by a given offset
*/
static void adj_time(offset)
register long offset;
{
struct timeval time_offset;
if (no_set)
return;
time_offset.tv_sec = offset / 1000000;
time_offset.tv_usec = offset % 1000000;
LPRINTF("adj_time: %ld us ", (long int)offset);
if (adjtime(&time_offset, 0L) == -1)
perror("adjtime()");
}
/*-----------------------------------------------------------------------
* read in a possibly previously written drift value
*/
static void read_drift(drift_file)
char *drift_file;
{
FILE *df;
df = fopen(drift_file, "r");
if (df != NULL)
{
int idrift, fdrift;
fscanf(df, "%4d.%03d", &idrift, &fdrift);
fclose(df);
LPRINTF("read_drift: %d.%03d ppm ", idrift, fdrift);
drift_comp = idrift << USECSCALE;
fdrift = (fdrift << USECSCALE) / 1000;
drift_comp += fdrift & (1<<USECSCALE);
LPRINTF("read_drift: drift_comp %ld ", (long int)drift_comp);
}
}
/*-----------------------------------------------------------------------
* write out the current drift value
*/
static void update_drift(drift_file, offset, reftime)
char *drift_file;
long offset;
time_t reftime;
{
FILE *df;
df = fopen(drift_file, "w");
if (df != NULL)
{
int idrift = R_SHIFT(drift_comp, USECSCALE);
int fdrift = drift_comp & ((1<<USECSCALE)-1);
LPRINTF("update_drift: drift_comp %ld ", (long int)drift_comp);
fdrift = (fdrift * 1000) / (1<<USECSCALE);
fprintf(df, "%4d.%03d %c%ld.%06ld %.24s\n", idrift, fdrift,
(offset < 0) ? '-' : '+', (long int)(abs(offset) / 1000000),
(long int)(abs(offset) % 1000000), asctime(localtime(&reftime)));
fclose(df);
LPRINTF("update_drift: %d.%03d ppm ", idrift, fdrift);
}
}
/*-----------------------------------------------------------------------
* process adjustments derived from the DCF77 observation
* (controls clock PLL)
*/
static void adjust_clock(offset, drift_file, reftime)
struct timeval *offset;
char *drift_file;
time_t reftime;
{
struct timeval toffset;
register long usecoffset;
int tmp;
if (no_set)
return;
if (skip_adjust)
{
skip_adjust = 0;
return;
}
toffset = *offset;
toffset.tv_sec = abs(toffset.tv_sec);
toffset.tv_usec = abs(toffset.tv_usec);
if (timercmp(&toffset, &max_adj_offset, >))
{
/*
* hopeless - set the clock - and clear the timing
*/
set_time(offset);
clock_adjust = 0;
skip_adjust = 1;
return;
}
usecoffset = offset->tv_sec * 1000000 + offset->tv_usec;
clock_adjust = R_SHIFT(usecoffset, TIMECONSTANT); /* adjustment to make for next period */
tmp = 0;
while (adjustments > (1 << tmp))
tmp++;
adjustments = 0;
if (tmp > FREQ_WEIGHT)
tmp = FREQ_WEIGHT;
drift_comp += R_SHIFT(usecoffset << USECSCALE, TIMECONSTANT+TIMECONSTANT+FREQ_WEIGHT-tmp);
if (drift_comp > MAX_DRIFT) /* clamp into interval */
drift_comp = MAX_DRIFT;
else
if (drift_comp < -MAX_DRIFT)
drift_comp = -MAX_DRIFT;
update_drift(drift_file, usecoffset, reftime);
LPRINTF("clock_adjust: %s, clock_adjust %ld, drift_comp %ld(%ld) ",
pr_timeval(offset),(long int) R_SHIFT(clock_adjust, USECSCALE),
(long int)R_SHIFT(drift_comp, USECSCALE), (long int)drift_comp);
}
/*-----------------------------------------------------------------------
* adjust the clock by a small mount to simulate frequency correction
*/
static void periodic_adjust()
{
register long adjustment;
adjustments++;
adjustment = R_SHIFT(clock_adjust, PHASE_WEIGHT);
clock_adjust -= adjustment;
adjustment += R_SHIFT(drift_comp, USECSCALE+ADJINTERVAL);
adj_time(adjustment);
}
/*-----------------------------------------------------------------------
* control synchronisation status (warnings) and do periodic adjusts
* (frequency control simulation)
*/
static void tick()
{
static unsigned long last_notice = 0;
#ifndef SV_ONSTACK
(void)signal(SIGALRM, tick);
#endif
periodic_adjust();
ticks += 1<<ADJINTERVAL;
if ((ticks - last_sync) > MAX_UNSYNC)
{
/*
* not getting time for a while
*/
if (sync_state == SYNC)
{
/*
* completely lost information
*/
sync_state = NO_SYNC;
syslog(LOG_INFO, "DCF77 reception lost (timeout)");
last_notice = ticks;
}
else
/*
* in NO_SYNC state - look whether its time to speak up again
*/
if ((ticks - last_notice) > NOTICE_INTERVAL)
{
syslog(LOG_NOTICE, "still not synchronized to DCF77 - check receiver/signal");
last_notice = ticks;
}
}
#ifndef ITIMER_REAL
(void) alarm(1<<ADJINTERVAL);
#endif
}
/*-----------------------------------------------------------------------
* break association from terminal to avoid catching terminal
* or process group related signals (-> daemon operation)
*/
static void detach()
{
int s;
if (fork())
exit(0);
for (s = 0; s < 3; s++)
(void) close(s);
(void) open("/", 0);
(void) dup2(0, 1);
(void) dup2(0, 2);
#if defined(NTP_POSIX_SOURCE) || defined(_POSIX_)
(void) setsid();
#else /* _POSIX_ */
#ifndef BSD
(void) setpgrp();
#else /* BSD */
(void) setpgrp(0, getpid());
#endif /* BSD */
#endif /* _POSIX_ */
#if defined(hpux)
if (fork())
exit(0);
#endif /* hpux */
}
/*-----------------------------------------------------------------------
* list possible arguments and options
*/
static void usage(program)
char *program;
{
fprintf(stderr, "usage: %s [-f] [-l] [-t] [-i] [-o] [-d <drift_file>] <device>\n", program);
fprintf(stderr, "\t-n do not change time\n");
fprintf(stderr, "\t-i interactive\n");
fprintf(stderr, "\t-t trace (print all datagrams)\n");
fprintf(stderr, "\t-f print all databits (includes PTB private data)\n");
fprintf(stderr, "\t-l print loop filter debug information\n");
fprintf(stderr, "\t-o print offet average for current minute\n");
fprintf(stderr, "\t-d <drift_file> specify alternate drift file\n");
fprintf(stderr, "\t-D <input delay>specify delay from input edge to processing in micro seconds\n");
}
/*-----------------------------------------------------------------------
* main loop - argument interpreter / setup / main loop
*/
int
main(argc, argv)
int argc;
char **argv;
{
unsigned char c;
char **a = argv;
int ac = argc;
char *file = NULL;
char *drift_file = "/etc/dcfd.drift";
int fd;
int offset = 15;
int offsets = 0;
int delay = DEFAULT_DELAY; /* average delay from input edge to time stamping */
int trace = 0;
int errs = 0;
/*
* process arguments
*/
while (--ac)
{
char *arg = *++a;
if (*arg == '-')
while ((c = *++arg))
switch (c)
{
case 't':
trace = 1;
interactive = 1;
break;
case 'f':
offset = 0;
interactive = 1;
break;
case 'l':
loop_filter_debug = 1;
offsets = 1;
interactive = 1;
break;
case 'n':
no_set = 1;
break;
case 'o':
offsets = 1;
interactive = 1;
break;
case 'i':
interactive = 1;
break;
case 'D':
if (ac > 1)
{
delay = atoi(*++a);
ac--;
}
else
{
fprintf(stderr, "%s: -D requires integer argument\n", argv[0]);
errs=1;
}
break;
case 'd':
if (ac > 1)
{
drift_file = *++a;
ac--;
}
else
{
fprintf(stderr, "%s: -d requires file name argument\n", argv[0]);
errs=1;
}
break;
default:
fprintf(stderr, "%s: unknown option -%c\n", argv[0], c);
errs=1;
break;
}
else
if (file == NULL)
file = arg;
else
{
fprintf(stderr, "%s: device specified twice\n", argv[0]);
errs=1;
}
}
if (errs)
{
usage(argv[0]);
exit(1);
}
else
if (file == NULL)
{
fprintf(stderr, "%s: device not specified\n", argv[0]);
usage(argv[0]);
exit(1);
}
errs = LINES+1;
/*
* get access to DCF77 tty port
*/
#if defined(SYS_FREEBSD) && defined(BOEDER)
fd = open(file, O_RDONLY | O_NONBLOCK);
#else
fd = open(file, O_RDONLY);
#endif
if (fd == -1)
{
perror(file);
exit(1);
}
else
{
int i, rrc;
struct timeval t, tt, tlast;
struct timeval timeout;
struct timeval phase;
struct timeval time_offset;
char pbuf[61]; /* printable version */
char buf[61]; /* raw data */
clocktime_t clock; /* wall clock time */
time_t utc_time = 0;
time_t last_utc_time = 0;
long usecerror = 0;
long lasterror = 0;
#if defined(HAVE_TERMIOS) || defined(STREAM)
struct termios term;
#endif
#if defined(HAVE_TERMIO) || defined(HAVE_SYSV_TTYS)
struct termio term;
#endif
int rtc = CVT_NONE;
timeout.tv_sec = 1;
timeout.tv_usec = 500000;
phase.tv_sec = 0;
phase.tv_usec = delay;
/*
* setup TTY (50 Baud, Read, 8Bit, No Hangup, 1 character IO)
*/
if (TTY_GETATTR(fd, &term) == -1)
{
perror("tcgetattr");
exit(1);
}
memset(term.c_cc, 0, sizeof(term.c_cc));
term.c_cc[VMIN] = 1;
#if defined(SYS_FREEBSD)
term.c_cflag = CS8|CREAD|CLOCAL|PARENB;
term.c_iflag = 0;
#else
term.c_cflag = B50|CS8|CREAD|CLOCAL|PARENB;
term.c_iflag = IGNPAR;
#endif
term.c_oflag = 0;
term.c_lflag = 0;
#if defined(SYS_FREEBSD)
if (cfsetspeed(&term, B50) == -1)
perror("cfsetspeed");
#endif
if (TTY_SETATTR(fd, &term) == -1)
{
perror("tcsetattr");
exit(1);
}
/*
* loose terminal if in daemon operation
*/
if (!interactive)
detach();
/*
* get syslog() initialized
*/
#ifdef LOG_DAEMON
openlog("dcfd", LOG_PID, LOG_DAEMON);
#else
openlog("dcfd", LOG_PID);
#endif
/*
* setup periodic operations (state control / frequency control)
*/
#ifdef SV_ONSTACK
{
struct sigvec vec;
vec.sv_handler = tick;
vec.sv_mask = 0;
vec.sv_flags = 0;
if (sigvec(SIGALRM, &vec, (struct sigvec *)0) == -1)
{
syslog(LOG_ERR, "sigvec(SIGALRM): %m");
exit(1);
}
}
#else
(void) signal(SIGALRM, tick);
#endif
#ifdef ITIMER_REAL
{
struct itimerval it;
it.it_interval.tv_sec = 1<<ADJINTERVAL;
it.it_interval.tv_usec = 0;
it.it_value.tv_sec = 1<<ADJINTERVAL;
it.it_value.tv_usec = 0;
if (setitimer(ITIMER_REAL, &it, (struct itimerval *)0) == -1)
{
syslog(LOG_ERR, "setitimer: %m");
exit(1);
}
}
#else
(void) alarm(1<<ADJINTERVAL);
#endif
#if defined(SYS_FREEBSD) && defined(BOEDER)
if (fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) & ~O_NONBLOCK) == -1)
perror("F_SETFL");
if (ioctl(fd, TIOCCDTR, 0) == -1)
perror("TIOCCDTR");
#endif
PRINTF(" DCF77 monitor - Copyright 1993,1994, Frank Kardel\n\n");
syslog(LOG_NOTICE, "Starting on %s", file);
pbuf[60] = '\0';
for ( i = 0; i < 60; i++)
pbuf[i] = '.';
read_drift(drift_file);
/*
* what time is it now (for interval measurement)
*/
gettimeofday(&tlast, 0L);
i = 0;
/*
* loop until input trouble ...
*/
do
{
/*
* get an impulse
*/
while ((rrc = read(fd, &c, 1)) == 1)
{
gettimeofday(&t, 0L);
tt = t;
timersub(&t, &tlast);
if (errs > LINES)
{
PRINTF(" %s", &"PTB private....RADMLSMin....PHour..PMDay..DayMonthYear....P\n"[offset]);
PRINTF(" %s", &"---------------RADMLS1248124P124812P1248121241248112481248P\n"[offset]);
errs = 0;
}
/*
* timeout -> possible minute mark -> interpretation
*/
if (timercmp(&t, &timeout, >))
{
PRINTF("%c %.*s ", pat[i % (sizeof(pat)-1)], 59 - offset, &pbuf[offset]);
if ((rtc = cvt_rawdcf(buf, i, &clock)) != CVT_OK)
{
/*
* this data was bad - well - forget synchronisation for now
*/
PRINTF("\n");
if (sync_state == SYNC)
{
sync_state = NO_SYNC;
syslog(LOG_INFO, "DCF77 reception lost (bad data)");
}
errs++;
}
else
if (trace)
{
PRINTF("\r %.*s ", 59 - offset, &buf[offset]);
}
buf[0] = c;
/*
* collect first character
*/
if (((c^0xFF)+1) & (c^0xFF))
pbuf[0] = '?';
else
pbuf[0] = type(c) ? '#' : '-';
for ( i = 1; i < 60; i++)
pbuf[i] = '.';
i = 0;
}
else
{
/*
* collect character
*/
buf[i] = c;
/*
* initial guess (usually correct)
*/
if (((c^0xFF)+1) & (c^0xFF))
pbuf[i] = '?';
else
pbuf[i] = type(c) ? '#' : '-';
PRINTF("%c %.*s ", pat[i % (sizeof(pat)-1)], 59 - offset, &pbuf[offset]);
}
if (i == 0 && rtc == CVT_OK)
{
/*
* we got a good time code here - try to convert it to
* UTC
*/
if ((utc_time = dcf_to_unixtime(&clock, &rtc)) == -1)
{
PRINTF("*** BAD CONVERSION\n");
}
if (utc_time != (last_utc_time + 60))
{
/*
* well, two successive sucessful telegrams are not 60 seconds
* apart
*/
PRINTF("*** NO MINUTE INC\n");
if (sync_state == SYNC)
{
sync_state = NO_SYNC;
syslog(LOG_INFO, "DCF77 reception lost (data mismatch)");
}
errs++;
rtc = CVT_FAIL|CVT_BADTIME|CVT_BADDATE;
}
else
usecerror = 0;
last_utc_time = utc_time;
}
if (rtc == CVT_OK)
{
if (i == 0)
{
/*
* valid time code - determine offset and
* note regained reception
*/
last_sync = ticks;
if (sync_state == NO_SYNC)
{
syslog(LOG_INFO, "receiving DCF77");
}
else
{
/*
* we had at least one minute SYNC - thus
* last error is valid
*/
#if defined(BOEDER)
time_offset.tv_sec = utc_time - tt.tv_sec;
time_offset.tv_usec = 0;
#else
time_offset.tv_sec = lasterror / 1000000;
time_offset.tv_usec = lasterror % 1000000;
#endif
adjust_clock(&time_offset, drift_file, utc_time);
}
sync_state = SYNC;
}
time_offset.tv_sec = utc_time + i;
time_offset.tv_usec = 0;
timeradd(&time_offset, &phase);
usecerror += (time_offset.tv_sec - tt.tv_sec) * 1000000 + time_offset.tv_usec
-tt.tv_usec;
/*
* output interpreted DCF77 data
*/
PRINTF(offsets ? "%s, %2d:%02d:%02d, %d.%02d.%02d, <%s%s%s%s> (%c%d.%06ds)" :
"%s, %2d:%02d:%02d, %d.%02d.%02d, <%s%s%s%s>",
wday[clock.wday],
clock.hour, clock.minute, i, clock.day, clock.month,
clock.year,
(clock.flags & DCFB_ALTERNATE) ? "R" : "_",
(clock.flags & DCFB_ANNOUNCE) ? "A" : "_",
(clock.flags & DCFB_DST) ? "D" : "_",
(clock.flags & DCFB_LEAP) ? "L" : "_",
(lasterror < 0) ? '-' : '+', abs(lasterror) / 1000000, abs(lasterror) % 1000000
);
if (trace && (i == 0))
{
PRINTF("\n");
errs++;
}
lasterror = usecerror / (i+1);
}
else
{
lasterror = 0; /* we cannot calculate phase errors on bad reception */
}
PRINTF("\r");
if (i < 60)
{
i++;
}
tlast = tt;
if (interactive)
fflush(stdout);
}
} while ((rrc == -1) && (errno == EINTR));
/*
* lost IO - sorry guys
*/
syslog(LOG_ERR, "TERMINATING - cannot read from device %s (%m)", file);
(void)close(fd);
}
closelog();
return 0;
}