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-rw-r--r--usr.sbin/xntpd/parse/util/dcfd.c503
1 files changed, 440 insertions, 63 deletions
diff --git a/usr.sbin/xntpd/parse/util/dcfd.c b/usr.sbin/xntpd/parse/util/dcfd.c
index 723e2c8e8cad6..23934a8e104ec 100644
--- a/usr.sbin/xntpd/parse/util/dcfd.c
+++ b/usr.sbin/xntpd/parse/util/dcfd.c
@@ -1,7 +1,7 @@
/*
- * /src/NTP/REPOSITORY/v3/parse/util/dcfd.c,v 3.8 1993/11/04 20:02:05 kardel Exp
+ * /src/NTP/REPOSITORY/v3/parse/util/dcfd.c,v 3.15 1994/01/25 19:05:42 kardel Exp
*
- * dcfd.c,v 3.8 1993/11/04 20:02:05 kardel Exp
+ * dcfd.c,v 3.15 1994/01/25 19:05:42 kardel Exp
*
* DCF77 100/200ms pulse synchronisation daemon program (via 50Baud serial line)
*
@@ -13,7 +13,7 @@
* Lacks:
* Leap second handling (at that level you should switch to xntp3 - really!)
*
- * Copyright (c) 1993
+ * Copyright (c) 1993,1994
* Frank Kardel, Friedrich-Alexander Universitaet Erlangen-Nuernberg
*
* This program is distributed in the hope that it will be useful,
@@ -33,6 +33,9 @@
#include <sys/errno.h>
#include <syslog.h>
+/*
+ * NTP compilation environment
+ */
#ifdef USE_PROTOTYPES
#include "ntp_stdlib.h"
extern int sigvec P((int, struct sigvec *, struct sigvec *));
@@ -43,6 +46,9 @@ extern int fscanf P((FILE *, char *, ...));
#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_))
@@ -63,24 +69,33 @@ MUST DEFINE ONE OF "HAVE_TERMIOS" or "HAVE_TERMIO"
#define dysize(_x_) (((_x_) % 4) ? 365 : (((_x_) % 400) ? 365 : 366))
#endif
-#define timernormalize(_a_, _b_) \
+#define timernormalize(_a_) \
if ((_a_)->tv_usec >= 1000000) \
{ \
(_a_)->tv_sec += (_a_)->tv_usec / 1000000; \
- (_a_)->tv_usec -= (_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_), (_b_))
+ timernormalize((_a_))
#define timersub(_a_, _b_) \
(_a_)->tv_sec -= (_b_)->tv_sec; \
(_a_)->tv_usec -= (_b_)->tv_usec; \
- timernormalize((_a_), (_b_))
+ timernormalize((_a_))
+/*
+ * debug macros
+ */
#define PRINTF if (interactive) printf
+#define LPRINTF if (interactive && loop_filter_debug) printf
#ifdef DEBUG
#define dprintf(_x_) PRINTF _x_
@@ -90,9 +105,31 @@ MUST DEFINE ONE OF "HAVE_TERMIOS" or "HAVE_TERMIO"
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
@@ -105,7 +142,7 @@ static char pat[] = "-\\|/";
#define LINES (24-2) /* error lines after which the two headlines are repeated */
-#define MAX_UNSYNC (5*60) /* allow synchronisation loss for 5 minutes */
+#define MAX_UNSYNC (10*60) /* allow synchronisation loss for 10 minutes */
#define NOTICE_INTERVAL (20*60) /* mention missing synchronisation every 20 minutes */
/*
@@ -113,7 +150,7 @@ static char pat[] = "-\\|/";
*/
#define USECSCALE 10
-#define TIMECONSTANT 0
+#define TIMECONSTANT 2
#define ADJINTERVAL 0
#define FREQ_WEIGHT 18
#define PHASE_WEIGHT 7
@@ -129,7 +166,7 @@ static long adjustments = 0;
static char skip_adjust = 1; /* discard first adjustment (bad samples) */
/*
- * state flags
+ * DCF77 state flags
*/
#define DCFB_ANNOUNCE 0x0001 /* switch time zone warning (DST switch) */
#define DCFB_DST 0x0002 /* DST in effect */
@@ -138,7 +175,7 @@ static char skip_adjust = 1; /* discard first adjustment (bad samples) */
struct clocktime /* clock time broken up from time code */
{
- long wday;
+ long wday; /* Day of week: 1: Monday - 7: Sunday */
long day;
long month;
long year;
@@ -147,18 +184,24 @@ struct clocktime /* clock time broken up from time code */
long second;
long usecond;
long utcoffset; /* in minutes */
- long flags; /* current clock status */
+ 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_))
/*
- * parser related return/error codes
+ * conversion related return/error codes
*/
#define CVT_MASK 0x0000000F /* conversion exit code */
#define CVT_NONE 0x00000001 /* format not applicable */
@@ -216,6 +259,14 @@ typedef struct clocktime clocktime_t;
* 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 */
@@ -225,6 +276,10 @@ static struct rawdcfcode
{ 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
@@ -246,6 +301,11 @@ static struct rawdcfcode
#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 */
@@ -254,6 +314,22 @@ static struct 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];
@@ -264,13 +340,13 @@ static struct dcfparam
"--------------------s-------p------p----------------------p" /* 'ZERO' representation */
};
-#define DCF_P_P1 0
-#define DCF_P_P2 1
-#define DCF_P_P3 2
-
-#define DCF_Z_MET 0x2
-#define DCF_Z_MED 0x1
-
+/*-----------------------------------------------------------------------
+ * 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;
@@ -288,6 +364,13 @@ static unsigned long ext_bf(buf, idx)
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;
@@ -303,6 +386,15 @@ static unsigned pcheck(buf, idx)
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;
@@ -323,7 +415,7 @@ static unsigned long convert_rawdcf(buffer, size, clock)
pcheck(buffer, DCF_P_P3))
{
/*
- * buffer OK
+ * buffer OK - extract all fields and build wall clock time from them
*/
clock->flags = 0;
@@ -341,6 +433,9 @@ static unsigned long convert_rawdcf(buffer, size, clock)
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:
@@ -357,6 +452,9 @@ static unsigned long convert_rawdcf(buffer, size, clock)
return CVT_FAIL|CVT_BADFMT;
}
+ /*
+ * extract various warnings from DCF77
+ */
if (ext_bf(buffer, DCF_A1))
clock->flags |= DCFB_ANNOUNCE;
@@ -378,7 +476,7 @@ static unsigned long convert_rawdcf(buffer, size, clock)
}
}
-/*
+/*-----------------------------------------------------------------------
* raw dcf input routine - fix up 50 baud
* characters for 1/0 decision
*/
@@ -402,8 +500,20 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
* 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;
@@ -412,15 +522,21 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
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;
/*
- * these lines are left as an excercise to the reader 8-)
+ * check integrity and update histogramm
*/
if (!((ch+1) & ch) || !*s)
{
-
+ /*
+ * character ok
+ */
for (i = 0; ch; i++)
{
ch >>= 1;
@@ -433,6 +549,9 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
}
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;
@@ -440,6 +559,10 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
s++;
}
+ /*
+ * first cutoff estimate (average bit count - must be between both
+ * maxima)
+ */
if (lowmax)
{
cutoff /= lowmax;
@@ -451,20 +574,31 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
dprintf(("parse: cvt_rawdcf: average bit count: %d\n", cutoff));
- lowmax = 0;
- highmax = 0;
+ 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;
+ 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;
@@ -474,9 +608,12 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
lowmax = 0;
}
- highmax = 0;
- cutoff = 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;
@@ -485,6 +622,9 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
}
dprintf(("\n"));
+ /*
+ * determine upper maximum (weighted sum / bit count)
+ */
if (cutoff)
{
highmax /= cutoff;
@@ -494,34 +634,64 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
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])
{
- cutoff = i;
- span = 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++;
@@ -529,11 +699,19 @@ static unsigned long cvt_rawdcf(buffer, size, clock)
c++;
}
+ /*
+ * if everything went well so far return the result of the symbolic
+ * conversion routine else just the accumulated errors
+ */
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
-parse_to_unixtime(clock, cvtrtc)
+dcf_to_unixtime(clock, cvtrtc)
register clocktime_t *clock;
register unsigned long *cvtrtc;
{
@@ -545,12 +723,22 @@ parse_to_unixtime(clock, cvtrtc)
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;
- if (clock->year < 1970)
- clock->year += 100; /* XXX this will do it till <2070 */
+ /*
+ * 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);
@@ -560,6 +748,10 @@ parse_to_unixtime(clock, cvtrtc)
/*
* 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;
@@ -570,10 +762,13 @@ parse_to_unixtime(clock, cvtrtc)
SETRTC(CVT_FAIL|CVT_BADDATE);
return -1; /* bad month */
}
- /* adjust leap year */
+ /* 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];
@@ -586,7 +781,11 @@ parse_to_unixtime(clock, cvtrtc)
return -1; /* bad day */
}
+ /*
+ * collect days from date excluding the current one
+ */
t += clock->day - 1;
+
/* hour */
if (clock->hour < 0 || clock->hour >= 24)
{
@@ -594,6 +793,9 @@ parse_to_unixtime(clock, cvtrtc)
return -1; /* bad hour */
}
+ /*
+ * calculate hours from 1. 1. 1970
+ */
t = TIMES24(t) + clock->hour;
/* min */
@@ -603,10 +805,16 @@ parse_to_unixtime(clock, cvtrtc)
return -1; /* bad min */
}
+ /*
+ * calculate minutes from 1. 1. 1970
+ */
t = TIMES60(t) + clock->minute;
/* sec */
- t += clock->utcoffset; /* warp to UTC */
+ /*
+ * calculate UTC in minutes
+ */
+ t += clock->utcoffset;
if (clock->second < 0 || clock->second > 60) /* allow for LEAPs */
{
@@ -614,12 +822,15 @@ parse_to_unixtime(clock, cvtrtc)
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)
@@ -629,6 +840,9 @@ unsigned char c;
return (c > 0xF);
}
+/*-----------------------------------------------------------------------
+ * week day representation
+ */
static char *wday[8] =
{
"??",
@@ -641,6 +855,9 @@ static char *wday[8] =
"Su"
};
+/*-----------------------------------------------------------------------
+ * generate a string representation for a timeval
+ */
static char * pr_timeval(val)
struct timeval *val;
{
@@ -653,11 +870,20 @@ static char * pr_timeval(val)
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;
- /*XXX*/ if (loop_filter_debug) printf("set_time: %s ", pr_timeval(offset));
+
+ 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()");
@@ -672,20 +898,28 @@ static void set_time(offset)
}
}
+/*-----------------------------------------------------------------------
+ * 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;
- /*XXX*/ if (loop_filter_debug)
- printf("adj_time: %d us ", offset);
+ LPRINTF("adj_time: %d us ", 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;
{
@@ -698,17 +932,18 @@ static void read_drift(drift_file)
fscanf(df, "%4d.%03d", &idrift, &fdrift);
fclose(df);
- /*XXX*/ if (loop_filter_debug)
- printf("read_drift: %d.%03d ppm ", idrift, fdrift);
+ LPRINTF("read_drift: %d.%03d ppm ", idrift, fdrift);
drift_comp = idrift << USECSCALE;
fdrift = (fdrift << USECSCALE) / 1000;
drift_comp += fdrift & (1<<USECSCALE);
- /*XXX*/ if (loop_filter_debug)
- printf("read_drift: drift_comp %d ", drift_comp);
+ LPRINTF("read_drift: drift_comp %d ", drift_comp);
}
}
+/*-----------------------------------------------------------------------
+ * write out the current drift value
+ */
static void update_drift(drift_file, offset, reftime)
char *drift_file;
long offset;
@@ -722,18 +957,20 @@ static void update_drift(drift_file, offset, reftime)
int idrift = R_SHIFT(drift_comp, USECSCALE);
int fdrift = drift_comp & ((1<<USECSCALE)-1);
- /*XXX*/ if (loop_filter_debug)
- printf("update_drift: drift_comp %d ", drift_comp);
+ LPRINTF("update_drift: drift_comp %d ", drift_comp);
fdrift = (fdrift * 1000) / (1<<USECSCALE);
fprintf(df, "%4d.%03d %c%d.%06d %.24s\n", idrift, fdrift,
(offset < 0) ? '-' : '+', abs(offset) / 1000000, abs(offset) % 1000000,
asctime(localtime(&reftime)));
fclose(df);
- /*XXX*/ if (loop_filter_debug)
- printf("update_drift: %d.%03d ppm ", idrift, fdrift);
+ 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;
@@ -743,6 +980,9 @@ static void adjust_clock(offset, drift_file, reftime)
register long usecoffset;
int tmp;
+ if (no_set)
+ return;
+
if (skip_adjust)
{
skip_adjust = 0;
@@ -783,11 +1023,13 @@ static void adjust_clock(offset, drift_file, reftime)
drift_comp = -MAX_DRIFT;
update_drift(drift_file, usecoffset, reftime);
- /*XXX*/ if (loop_filter_debug)
- printf("clock_adjust: %s, clock_adjust %d, drift_comp %d(%d) ",
+ LPRINTF("clock_adjust: %s, clock_adjust %d, drift_comp %d(%d) ",
pr_timeval(offset), R_SHIFT(clock_adjust, USECSCALE) , R_SHIFT(drift_comp, USECSCALE), drift_comp);
}
+/*-----------------------------------------------------------------------
+ * adjust the clock by a small mount to simulate frequency correction
+ */
static void periodic_adjust()
{
register long adjustment;
@@ -803,9 +1045,13 @@ static void periodic_adjust()
adj_time(adjustment);
}
+/*-----------------------------------------------------------------------
+ * control synchronisation status (warnings) and do periodic adjusts
+ * (frequency control simulation)
+ */
static void tick()
{
- static unsigned long last_notice;
+ static unsigned long last_notice = 0;
#ifndef SV_ONSTACK
(void)signal(SIGALRM, tick);
@@ -815,11 +1061,29 @@ static void tick()
ticks += 1<<ADJINTERVAL;
- if ((sync_state == NO_SYNC) && ((ticks - last_sync) > MAX_UNSYNC) &&
- ((last_notice - ticks) > NOTICE_INTERVAL))
+ if ((ticks - last_sync) > MAX_UNSYNC)
{
- syslog(LOG_NOTICE, "still not synchronized - check receiver/signal");
- last_notice = ticks;
+ /*
+ * 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
@@ -827,6 +1091,10 @@ static void tick()
#endif
}
+/*-----------------------------------------------------------------------
+ * break association from terminal to avaoid catching terminal
+ * or process group related signals (-> daemon operation)
+ */
static void detach()
{
int s;
@@ -855,18 +1123,26 @@ static void detach()
#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;
@@ -880,9 +1156,13 @@ main(argc, argv)
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;
@@ -906,6 +1186,10 @@ main(argc, argv)
interactive = 1;
break;
+ case 'n':
+ no_set = 1;
+ break;
+
case 'o':
offsets = 1;
interactive = 1;
@@ -915,6 +1199,19 @@ main(argc, argv)
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)
{
@@ -958,6 +1255,9 @@ main(argc, argv)
errs = LINES+1;
+ /*
+ * get access to DCF77 tty port
+ */
fd = open(file, O_RDONLY);
if (fd == -1)
{
@@ -975,6 +1275,7 @@ main(argc, argv)
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)
@@ -989,8 +1290,11 @@ main(argc, argv)
timeout.tv_usec = 500000;
phase.tv_sec = 0;
- phase.tv_usec = 230000;
+ phase.tv_usec = delay;
+ /*
+ * setup TTY (50 Baud, Read, 8Bit, No Hangup, 1 character IO)
+ */
if (TTY_GETATTR(fd, &term) == -1)
{
perror("tcgetattr");
@@ -1010,15 +1314,24 @@ main(argc, argv)
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;
@@ -1064,10 +1377,19 @@ main(argc, argv)
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);
@@ -1081,23 +1403,32 @@ main(argc, argv)
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_DEBUG, "DCF77 reception lost");
+ syslog(LOG_INFO, "DCF77 reception lost (bad data)");
}
errs++;
}
buf[0] = c;
+ /*
+ * collect first character
+ */
if (((c^0xFF)+1) & (c^0xFF))
pbuf[0] = '?';
else
@@ -1110,6 +1441,9 @@ main(argc, argv)
}
else
{
+ /*
+ * collect character
+ */
buf[i] = c;
/*
@@ -1125,12 +1459,34 @@ main(argc, argv)
if (i == 0 && rtc == CVT_OK)
{
- if ((utc_time = parse_to_unixtime(&clock, &rtc)) == -1)
+ /*
+ * 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");
}
- usecerror = 0;
+ 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)
@@ -1142,14 +1498,25 @@ main(argc, argv)
if (i == 0)
{
- time_offset.tv_sec = lasterror / 1000000;
- time_offset.tv_usec = lasterror % 1000000;
- adjust_clock(&time_offset, drift_file, utc_time+i);
+ /*
+ * 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
+ */
+ time_offset.tv_sec = lasterror / 1000000;
+ time_offset.tv_usec = lasterror % 1000000;
+ adjust_clock(&time_offset, drift_file, utc_time);
+ }
sync_state = SYNC;
}
@@ -1161,6 +1528,9 @@ main(argc, argv)
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],
@@ -1180,6 +1550,10 @@ main(argc, argv)
}
lasterror = usecerror / (i+1);
}
+ else
+ {
+ lasterror = 0; /* we cannot calculate phase errors on bad reception */
+ }
PRINTF("\r");
@@ -1195,7 +1569,10 @@ main(argc, argv)
}
} while ((rrc == -1) && (errno == EINTR));
- syslog(LOG_ERR, "TERMINATING - cannot read from device %s", file);
+ /*
+ * lost IO - sorry guys
+ */
+ syslog(LOG_ERR, "TERMINATING - cannot read from device %s (%m)", file);
(void)close(fd);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-02 05:51:06 +0000