chutest.c revision 54359
154359Sroberto/* chutest.c,v 3.1 1993/07/06 01:05:21 jbj Exp 254359Sroberto * chutest - test the CHU clock 354359Sroberto */ 454359Sroberto 554359Sroberto#include <stdio.h> 654359Sroberto#include <sys/types.h> 754359Sroberto#include <sys/socket.h> 854359Sroberto#include <netinet/in.h> 954359Sroberto#include <sys/ioctl.h> 1054359Sroberto#include <sys/time.h> 1154359Sroberto#include <sys/file.h> 1254359Sroberto#include <sgtty.h> 1354359Sroberto 1454359Sroberto#include "../include/ntp_fp.h" 1554359Sroberto#include "../include/ntp.h" 1654359Sroberto#include "../include/ntp_unixtime.h" 1754359Sroberto 1854359Sroberto#ifdef CHULDISC 1954359Sroberto#ifdef STREAM 2054359Sroberto# ifdef HAVE_SYS_CHUDEFS_H 2154359Sroberto#include <sys/chudefs.h> 2254359Sroberto#endif 2354359Sroberto#include <stropts.h> 2454359Sroberto#endif 2554359Sroberto#endif 2654359Sroberto 2754359Sroberto#ifdef CHULDISC 2854359Sroberto# ifdef HAVE_SYS_CHUDEFS_H 2954359Sroberto#include <sys/chudefs.h> 3054359Sroberto#endif 3154359Sroberto#endif 3254359Sroberto 3354359Sroberto#ifndef CHULDISC 3454359Sroberto#ifndef STREAM 3554359Sroberto#define NCHUCHARS (10) 3654359Sroberto 3754359Srobertostruct chucode { 3854359Sroberto u_char codechars[NCHUCHARS]; /* code characters */ 3954359Sroberto u_char ncodechars; /* number of code characters */ 4054359Sroberto u_char chustatus; /* not used currently */ 4154359Sroberto struct timeval codetimes[NCHUCHARS]; /* arrival times */ 4254359Sroberto}; 4354359Sroberto#endif 4454359Sroberto#endif 4554359Sroberto 4654359Sroberto#define STREQ(a, b) (*(a) == *(b) && strcmp((a), (b)) == 0) 4754359Sroberto 4854359Srobertochar *progname; 4954359Srobertoint debug; 5054359Sroberto 5154359Srobertoint dofilter = 0; /* set to 1 when we should run filter algorithm */ 5254359Srobertoint showtimes = 0; /* set to 1 when we should show char arrival times */ 5354359Srobertoint doprocess = 0; /* set to 1 when we do processing analogous to driver */ 5454359Sroberto#ifdef CHULDISC 5554359Srobertoint usechuldisc = 0; /* set to 1 when CHU line discipline should be used */ 5654359Sroberto#endif 5754359Sroberto#ifdef STREAM 5854359Srobertoint usechuldisc = 0; /* set to 1 when CHU line discipline should be used */ 5954359Sroberto#endif 6054359Sroberto 6154359Srobertostruct timeval lasttv; 6254359Srobertostruct chucode chudata; 6354359Sroberto 6454359Srobertoextern u_long ustotslo[]; 6554359Srobertoextern u_long ustotsmid[]; 6654359Srobertoextern u_long ustotshi[]; 6754359Sroberto 6854359Sroberto/* 6954359Sroberto * main - parse arguments and handle options 7054359Sroberto */ 7154359Srobertoint 7254359Srobertomain( 7354359Sroberto int argc, 7454359Sroberto char *argv[] 7554359Sroberto ) 7654359Sroberto{ 7754359Sroberto int c; 7854359Sroberto int errflg = 0; 7954359Sroberto extern int ntp_optind; 8054359Sroberto extern char *ntp_optarg; 8154359Sroberto void init_chu(); 8254359Sroberto 8354359Sroberto progname = argv[0]; 8454359Sroberto while ((c = ntp_getopt(argc, argv, "cdfpt")) != EOF) 8554359Sroberto switch (c) { 8654359Sroberto case 'c': 8754359Sroberto#ifdef STREAM 8854359Sroberto usechuldisc = 1; 8954359Sroberto break; 9054359Sroberto#endif 9154359Sroberto#ifdef CHULDISC 9254359Sroberto usechuldisc = 1; 9354359Sroberto break; 9454359Sroberto#endif 9554359Sroberto#ifndef STREAM 9654359Sroberto#ifndef CHULDISC 9754359Sroberto (void) fprintf(stderr, 9854359Sroberto "%s: CHU line discipline not available on this machine\n", 9954359Sroberto progname); 10054359Sroberto exit(2); 10154359Sroberto#endif 10254359Sroberto#endif 10354359Sroberto case 'd': 10454359Sroberto ++debug; 10554359Sroberto break; 10654359Sroberto case 'f': 10754359Sroberto dofilter = 1; 10854359Sroberto break; 10954359Sroberto case 'p': 11054359Sroberto doprocess = 1; 11154359Sroberto case 't': 11254359Sroberto showtimes = 1; 11354359Sroberto break; 11454359Sroberto default: 11554359Sroberto errflg++; 11654359Sroberto break; 11754359Sroberto } 11854359Sroberto if (errflg || ntp_optind+1 != argc) { 11954359Sroberto#ifdef STREAM 12054359Sroberto (void) fprintf(stderr, "usage: %s [-dft] tty_device\n", 12154359Sroberto progname); 12254359Sroberto#endif 12354359Sroberto#ifdef CHULDISC 12454359Sroberto (void) fprintf(stderr, "usage: %s [-dft] tty_device\n", 12554359Sroberto progname); 12654359Sroberto#endif 12754359Sroberto#ifndef STREAM 12854359Sroberto#ifndef CHULDISC 12954359Sroberto (void) fprintf(stderr, "usage: %s [-cdft] tty_device\n", 13054359Sroberto progname); 13154359Sroberto#endif 13254359Sroberto#endif 13354359Sroberto exit(2); 13454359Sroberto } 13554359Sroberto 13654359Sroberto (void) gettimeofday(&lasttv, (struct timezone *)0); 13754359Sroberto c = openterm(argv[ntp_optind]); 13854359Sroberto init_chu(); 13954359Sroberto#ifdef STREAM 14054359Sroberto if (usechuldisc) 14154359Sroberto process_ldisc(c); 14254359Sroberto else 14354359Sroberto#endif 14454359Sroberto#ifdef CHULDISC 14554359Sroberto if (usechuldisc) 14654359Sroberto process_ldisc(c); 14754359Sroberto else 14854359Sroberto#endif 14954359Sroberto process_raw(c); 15054359Sroberto /*NOTREACHED*/ 15154359Sroberto} 15254359Sroberto 15354359Sroberto 15454359Sroberto/* 15554359Sroberto * openterm - open a port to the CHU clock 15654359Sroberto */ 15754359Srobertoint 15854359Srobertoopenterm( 15954359Sroberto char *dev 16054359Sroberto ) 16154359Sroberto{ 16254359Sroberto int s; 16354359Sroberto struct sgttyb ttyb; 16454359Sroberto 16554359Sroberto if (debug) 16654359Sroberto (void) fprintf(stderr, "Doing open..."); 16754359Sroberto if ((s = open(dev, O_RDONLY, 0777)) < 0) 16854359Sroberto error("open(%s)", dev, ""); 16954359Sroberto if (debug) 17054359Sroberto (void) fprintf(stderr, "open okay\n"); 17154359Sroberto 17254359Sroberto if (debug) 17354359Sroberto (void) fprintf(stderr, "Setting exclusive use..."); 17454359Sroberto if (ioctl(s, TIOCEXCL, (char *)0) < 0) 17554359Sroberto error("ioctl(TIOCEXCL)", "", ""); 17654359Sroberto if (debug) 17754359Sroberto (void) fprintf(stderr, "done\n"); 17854359Sroberto 17954359Sroberto ttyb.sg_ispeed = ttyb.sg_ospeed = B300; 18054359Sroberto ttyb.sg_erase = ttyb.sg_kill = 0; 18154359Sroberto ttyb.sg_flags = EVENP|ODDP|RAW; 18254359Sroberto if (debug) 18354359Sroberto (void) fprintf(stderr, "Setting baud rate et al..."); 18454359Sroberto if (ioctl(s, TIOCSETP, (char *)&ttyb) < 0) 18554359Sroberto error("ioctl(TIOCSETP, raw)", "", ""); 18654359Sroberto if (debug) 18754359Sroberto (void) fprintf(stderr, "done\n"); 18854359Sroberto 18954359Sroberto#ifdef CHULDISC 19054359Sroberto if (usechuldisc) { 19154359Sroberto int ldisc; 19254359Sroberto 19354359Sroberto if (debug) 19454359Sroberto (void) fprintf(stderr, "Switching to CHU ldisc..."); 19554359Sroberto ldisc = CHULDISC; 19654359Sroberto if (ioctl(s, TIOCSETD, (char *)&ldisc) < 0) 19754359Sroberto error("ioctl(TIOCSETD, CHULDISC)", "", ""); 19854359Sroberto if (debug) 19954359Sroberto (void) fprintf(stderr, "okay\n"); 20054359Sroberto } 20154359Sroberto#endif 20254359Sroberto#ifdef STREAM 20354359Sroberto if (usechuldisc) { 20454359Sroberto 20554359Sroberto if (debug) 20654359Sroberto (void) fprintf(stderr, "Poping off streams..."); 20754359Sroberto while (ioctl(s, I_POP, 0) >=0) ; 20854359Sroberto if (debug) 20954359Sroberto (void) fprintf(stderr, "okay\n"); 21054359Sroberto if (debug) 21154359Sroberto (void) fprintf(stderr, "Pushing CHU stream..."); 21254359Sroberto if (ioctl(s, I_PUSH, "chu") < 0) 21354359Sroberto error("ioctl(I_PUSH, \"chu\")", "", ""); 21454359Sroberto if (debug) 21554359Sroberto (void) fprintf(stderr, "okay\n"); 21654359Sroberto } 21754359Sroberto#endif 21854359Sroberto return s; 21954359Sroberto} 22054359Sroberto 22154359Sroberto 22254359Sroberto/* 22354359Sroberto * process_raw - process characters in raw mode 22454359Sroberto */ 22554359Srobertoint 22654359Srobertoprocess_raw( 22754359Sroberto int s 22854359Sroberto ) 22954359Sroberto{ 23054359Sroberto u_char c; 23154359Sroberto int n; 23254359Sroberto struct timeval tv; 23354359Sroberto struct timeval difftv; 23454359Sroberto 23554359Sroberto while ((n = read(s, &c, sizeof(char))) > 0) { 23654359Sroberto (void) gettimeofday(&tv, (struct timezone *)0); 23754359Sroberto if (dofilter) 23854359Sroberto raw_filter((unsigned int)c, &tv); 23954359Sroberto else { 24054359Sroberto difftv.tv_sec = tv.tv_sec - lasttv.tv_sec; 24154359Sroberto difftv.tv_usec = tv.tv_usec - lasttv.tv_usec; 24254359Sroberto if (difftv.tv_usec < 0) { 24354359Sroberto difftv.tv_sec--; 24454359Sroberto difftv.tv_usec += 1000000; 24554359Sroberto } 24654359Sroberto (void) printf("%02x\t%lu.%06lu\t%lu.%06lu\n", 24754359Sroberto c, tv.tv_sec, tv.tv_usec, difftv.tv_sec, 24854359Sroberto difftv.tv_usec); 24954359Sroberto lasttv = tv; 25054359Sroberto } 25154359Sroberto } 25254359Sroberto 25354359Sroberto if (n == 0) { 25454359Sroberto (void) fprintf(stderr, "%s: zero returned on read\n", progname); 25554359Sroberto exit(1); 25654359Sroberto } else 25754359Sroberto error("read()", "", ""); 25854359Sroberto} 25954359Sroberto 26054359Sroberto 26154359Sroberto/* 26254359Sroberto * raw_filter - run the line discipline filter over raw data 26354359Sroberto */ 26454359Srobertoint 26554359Srobertoraw_filter( 26654359Sroberto unsigned int c, 26754359Sroberto struct timeval *tv 26854359Sroberto ) 26954359Sroberto{ 27054359Sroberto static struct timeval diffs[10] = { 0 }; 27154359Sroberto struct timeval diff; 27254359Sroberto l_fp ts; 27354359Sroberto void chufilter(); 27454359Sroberto 27554359Sroberto if ((c & 0xf) > 9 || ((c>>4)&0xf) > 9) { 27654359Sroberto if (debug) 27754359Sroberto (void) fprintf(stderr, 27854359Sroberto "character %02x failed BCD test\n"); 27954359Sroberto chudata.ncodechars = 0; 28054359Sroberto return; 28154359Sroberto } 28254359Sroberto 28354359Sroberto if (chudata.ncodechars > 0) { 28454359Sroberto diff.tv_sec = tv->tv_sec 28554359Sroberto - chudata.codetimes[chudata.ncodechars].tv_sec; 28654359Sroberto diff.tv_usec = tv->tv_usec 28754359Sroberto - chudata.codetimes[chudata.ncodechars].tv_usec; 28854359Sroberto if (diff.tv_usec < 0) { 28954359Sroberto diff.tv_sec--; 29054359Sroberto diff.tv_usec += 1000000; 29154359Sroberto } /* 29254359Sroberto if (diff.tv_sec != 0 || diff.tv_usec > 900000) { 29354359Sroberto if (debug) 29454359Sroberto (void) fprintf(stderr, 29554359Sroberto "character %02x failed time test\n"); 29654359Sroberto chudata.ncodechars = 0; 29754359Sroberto return; 29854359Sroberto } */ 29954359Sroberto } 30054359Sroberto 30154359Sroberto chudata.codechars[chudata.ncodechars] = c; 30254359Sroberto chudata.codetimes[chudata.ncodechars] = *tv; 30354359Sroberto if (chudata.ncodechars > 0) 30454359Sroberto diffs[chudata.ncodechars] = diff; 30554359Sroberto if (++chudata.ncodechars == 10) { 30654359Sroberto if (doprocess) { 30754359Sroberto TVTOTS(&chudata.codetimes[NCHUCHARS-1], &ts); 30854359Sroberto ts.l_ui += JAN_1970; 30954359Sroberto chufilter(&chudata, &chudata.codetimes[NCHUCHARS-1]); 31054359Sroberto } else { 31154359Sroberto register int i; 31254359Sroberto 31354359Sroberto for (i = 0; i < chudata.ncodechars; i++) { 31454359Sroberto (void) printf("%x%x\t%lu.%06lu\t%lu.%06lu\n", 31554359Sroberto chudata.codechars[i] & 0xf, 31654359Sroberto (chudata.codechars[i] >>4 ) & 0xf, 31754359Sroberto chudata.codetimes[i].tv_sec, 31854359Sroberto chudata.codetimes[i].tv_usec, 31954359Sroberto diffs[i].tv_sec, diffs[i].tv_usec); 32054359Sroberto } 32154359Sroberto } 32254359Sroberto chudata.ncodechars = 0; 32354359Sroberto } 32454359Sroberto} 32554359Sroberto 32654359Sroberto 32754359Sroberto/* #ifdef CHULDISC*/ 32854359Sroberto/* 32954359Sroberto * process_ldisc - process line discipline 33054359Sroberto */ 33154359Srobertoint 33254359Srobertoprocess_ldisc( 33354359Sroberto int s 33454359Sroberto ) 33554359Sroberto{ 33654359Sroberto struct chucode chu; 33754359Sroberto int n; 33854359Sroberto register int i; 33954359Sroberto struct timeval diff; 34054359Sroberto l_fp ts; 34154359Sroberto void chufilter(); 34254359Sroberto 34354359Sroberto while ((n = read(s, (char *)&chu, sizeof chu)) > 0) { 34454359Sroberto if (n != sizeof chu) { 34554359Sroberto (void) fprintf(stderr, "Expected %d, got %d\n", 34654359Sroberto sizeof chu, n); 34754359Sroberto continue; 34854359Sroberto } 34954359Sroberto 35054359Sroberto if (doprocess) { 35154359Sroberto TVTOTS(&chu.codetimes[NCHUCHARS-1], &ts); 35254359Sroberto ts.l_ui += JAN_1970; 35354359Sroberto chufilter(&chu, &ts); 35454359Sroberto } else { 35554359Sroberto for (i = 0; i < NCHUCHARS; i++) { 35654359Sroberto if (i == 0) 35754359Sroberto diff.tv_sec = diff.tv_usec = 0; 35854359Sroberto else { 35954359Sroberto diff.tv_sec = chu.codetimes[i].tv_sec 36054359Sroberto - chu.codetimes[i-1].tv_sec; 36154359Sroberto diff.tv_usec = chu.codetimes[i].tv_usec 36254359Sroberto - chu.codetimes[i-1].tv_usec; 36354359Sroberto if (diff.tv_usec < 0) { 36454359Sroberto diff.tv_sec--; 36554359Sroberto diff.tv_usec += 1000000; 36654359Sroberto } 36754359Sroberto } 36854359Sroberto (void) printf("%x%x\t%lu.%06lu\t%lu.%06lu\n", 36954359Sroberto chu.codechars[i] & 0xf, (chu.codechars[i]>>4)&0xf, 37054359Sroberto chu.codetimes[i].tv_sec, chu.codetimes[i].tv_usec, 37154359Sroberto diff.tv_sec, diff.tv_usec); 37254359Sroberto } 37354359Sroberto } 37454359Sroberto } 37554359Sroberto if (n == 0) { 37654359Sroberto (void) fprintf(stderr, "%s: zero returned on read\n", progname); 37754359Sroberto exit(1); 37854359Sroberto } else 37954359Sroberto error("read()", "", ""); 38054359Sroberto} 38154359Sroberto/*#endif*/ 38254359Sroberto 38354359Sroberto 38454359Sroberto/* 38554359Sroberto * error - print an error message 38654359Sroberto */ 38754359Srobertovoid 38854359Srobertoerror( 38954359Sroberto char *fmt, 39054359Sroberto char *s1, 39154359Sroberto char *s2 39254359Sroberto ) 39354359Sroberto{ 39454359Sroberto (void) fprintf(stderr, "%s: ", progname); 39554359Sroberto (void) fprintf(stderr, fmt, s1, s2); 39654359Sroberto (void) fprintf(stderr, ": "); 39754359Sroberto perror(""); 39854359Sroberto exit(1); 39954359Sroberto} 40054359Sroberto 40154359Sroberto/* 40254359Sroberto * Definitions 40354359Sroberto */ 40454359Sroberto#define MAXUNITS 4 /* maximum number of CHU units permitted */ 40554359Sroberto#define CHUDEV "/dev/chu%d" /* device we open. %d is unit number */ 40654359Sroberto#define NCHUCODES 9 /* expect 9 CHU codes per minute */ 40754359Sroberto 40854359Sroberto/* 40954359Sroberto * When CHU is operating optimally we want the primary clock distance 41054359Sroberto * to come out at 300 ms. Thus, peer.distance in the CHU peer structure 41154359Sroberto * is set to 290 ms and we compute delays which are at least 10 ms long. 41254359Sroberto * The following are 290 ms and 10 ms expressed in u_fp format 41354359Sroberto */ 41454359Sroberto#define CHUDISTANCE 0x00004a3d 41554359Sroberto#define CHUBASEDELAY 0x0000028f 41654359Sroberto 41754359Sroberto/* 41854359Sroberto * To compute a quality for the estimate (a pseudo delay) we add a 41954359Sroberto * fixed 10 ms for each missing code in the minute and add to this 42054359Sroberto * the sum of the differences between the remaining offsets and the 42154359Sroberto * estimated sample offset. 42254359Sroberto */ 42354359Sroberto#define CHUDELAYPENALTY 0x0000028f 42454359Sroberto 42554359Sroberto/* 42654359Sroberto * Other constant stuff 42754359Sroberto */ 42854359Sroberto#define CHUPRECISION (-9) /* what the heck */ 42954359Sroberto#define CHUREFID "CHU\0" 43054359Sroberto 43154359Sroberto/* 43254359Sroberto * Default fudge factors 43354359Sroberto */ 43454359Sroberto#define DEFPROPDELAY 0x00624dd3 /* 0.0015 seconds, 1.5 ms */ 43554359Sroberto#define DEFFILTFUDGE 0x000d1b71 /* 0.0002 seconds, 200 us */ 43654359Sroberto 43754359Sroberto/* 43854359Sroberto * Hacks to avoid excercising the multiplier. I have no pride. 43954359Sroberto */ 44054359Sroberto#define MULBY10(x) (((x)<<3) + ((x)<<1)) 44154359Sroberto#define MULBY60(x) (((x)<<6) - ((x)<<2)) /* watch overflow */ 44254359Sroberto#define MULBY24(x) (((x)<<4) + ((x)<<3)) 44354359Sroberto 44454359Sroberto/* 44554359Sroberto * Constants for use when multiplying by 0.1. ZEROPTONE is 0.1 44654359Sroberto * as an l_fp fraction, NZPOBITS is the number of significant bits 44754359Sroberto * in ZEROPTONE. 44854359Sroberto */ 44954359Sroberto#define ZEROPTONE 0x1999999a 45054359Sroberto#define NZPOBITS 29 45154359Sroberto 45254359Sroberto/* 45354359Sroberto * The CHU table. This gives the expected time of arrival of each 45454359Sroberto * character after the on-time second and is computed as follows: 45554359Sroberto * The CHU time code is sent at 300 bps. Your average UART will 45654359Sroberto * synchronize at the edge of the start bit and will consider the 45754359Sroberto * character complete at the center of the first stop bit, i.e. 45854359Sroberto * 0.031667 ms later. Thus the expected time of each interrupt 45954359Sroberto * is the start bit time plus 0.031667 seconds. These times are 46054359Sroberto * in chutable[]. To this we add such things as propagation delay 46154359Sroberto * and delay fudge factor. 46254359Sroberto */ 46354359Sroberto#define CHARDELAY 0x081b4e80 46454359Sroberto 46554359Srobertostatic u_long chutable[NCHUCHARS] = { 46654359Sroberto 0x2147ae14 + CHARDELAY, /* 0.130 (exactly) */ 46754359Sroberto 0x2ac08312 + CHARDELAY, /* 0.167 (exactly) */ 46854359Sroberto 0x34395810 + CHARDELAY, /* 0.204 (exactly) */ 46954359Sroberto 0x3db22d0e + CHARDELAY, /* 0.241 (exactly) */ 47054359Sroberto 0x472b020c + CHARDELAY, /* 0.278 (exactly) */ 47154359Sroberto 0x50a3d70a + CHARDELAY, /* 0.315 (exactly) */ 47254359Sroberto 0x5a1cac08 + CHARDELAY, /* 0.352 (exactly) */ 47354359Sroberto 0x63958106 + CHARDELAY, /* 0.389 (exactly) */ 47454359Sroberto 0x6d0e5604 + CHARDELAY, /* 0.426 (exactly) */ 47554359Sroberto 0x76872b02 + CHARDELAY, /* 0.463 (exactly) */ 47654359Sroberto}; 47754359Sroberto 47854359Sroberto/* 47954359Sroberto * Keep the fudge factors separately so they can be set even 48054359Sroberto * when no clock is configured. 48154359Sroberto */ 48254359Srobertostatic l_fp propagation_delay; 48354359Srobertostatic l_fp fudgefactor; 48454359Srobertostatic l_fp offset_fudge; 48554359Sroberto 48654359Sroberto/* 48754359Sroberto * We keep track of the start of the year, watching for changes. 48854359Sroberto * We also keep track of whether the year is a leap year or not. 48954359Sroberto * All because stupid CHU doesn't include the year in the time code. 49054359Sroberto */ 49154359Srobertostatic u_long yearstart; 49254359Sroberto 49354359Sroberto/* 49454359Sroberto * Imported from the timer module 49554359Sroberto */ 49654359Srobertoextern u_long current_time; 49754359Srobertoextern struct event timerqueue[]; 49854359Sroberto 49954359Sroberto/* 50054359Sroberto * Time conversion tables imported from the library 50154359Sroberto */ 50254359Srobertoextern u_long ustotslo[]; 50354359Srobertoextern u_long ustotsmid[]; 50454359Srobertoextern u_long ustotshi[]; 50554359Sroberto 50654359Sroberto 50754359Sroberto/* 50854359Sroberto * init_chu - initialize internal chu driver data 50954359Sroberto */ 51054359Srobertovoid 51154359Srobertoinit_chu(void) 51254359Sroberto{ 51354359Sroberto 51454359Sroberto /* 51554359Sroberto * Initialize fudge factors to default. 51654359Sroberto */ 51754359Sroberto propagation_delay.l_ui = 0; 51854359Sroberto propagation_delay.l_uf = DEFPROPDELAY; 51954359Sroberto fudgefactor.l_ui = 0; 52054359Sroberto fudgefactor.l_uf = DEFFILTFUDGE; 52154359Sroberto offset_fudge = propagation_delay; 52254359Sroberto L_ADD(&offset_fudge, &fudgefactor); 52354359Sroberto 52454359Sroberto yearstart = 0; 52554359Sroberto} 52654359Sroberto 52754359Sroberto 52854359Srobertovoid 52954359Srobertochufilter( 53054359Sroberto struct chucode *chuc, 53154359Sroberto l_fp *rtime 53254359Sroberto ) 53354359Sroberto{ 53454359Sroberto register int i; 53554359Sroberto register u_long date_ui; 53654359Sroberto register u_long tmp; 53754359Sroberto register u_char *code; 53854359Sroberto int isneg; 53954359Sroberto int imin; 54054359Sroberto int imax; 54154359Sroberto u_long reftime; 54254359Sroberto l_fp off[NCHUCHARS]; 54354359Sroberto l_fp ts; 54454359Sroberto int day, hour, minute, second; 54554359Sroberto static u_char lastcode[NCHUCHARS]; 54654359Sroberto extern u_long calyearstart(); 54754359Sroberto extern char *mfptoa(); 54854359Sroberto void chu_process(); 54954359Sroberto extern char *prettydate(); 55054359Sroberto 55154359Sroberto /* 55254359Sroberto * We'll skip the checks made in the kernel, but assume they've 55354359Sroberto * been done. This means that all characters are BCD and 55454359Sroberto * the intercharacter spacing isn't unreasonable. 55554359Sroberto */ 55654359Sroberto 55754359Sroberto /* 55854359Sroberto * print the code 55954359Sroberto */ 56054359Sroberto for (i = 0; i < NCHUCHARS; i++) 56154359Sroberto printf("%c%c", (chuc->codechars[i] & 0xf) + '0', 56254359Sroberto ((chuc->codechars[i]>>4) & 0xf) + '0'); 56354359Sroberto printf("\n"); 56454359Sroberto 56554359Sroberto /* 56654359Sroberto * Format check. Make sure the two halves match. 56754359Sroberto */ 56854359Sroberto for (i = 0; i < NCHUCHARS/2; i++) 56954359Sroberto if (chuc->codechars[i] != chuc->codechars[i+(NCHUCHARS/2)]) { 57054359Sroberto (void) printf("Bad format, halves don't match\n"); 57154359Sroberto return; 57254359Sroberto } 57354359Sroberto 57454359Sroberto /* 57554359Sroberto * Break out the code into the BCD nibbles. Only need to fiddle 57654359Sroberto * with the first half since both are identical. Note the first 57754359Sroberto * BCD character is the low order nibble, the second the high order. 57854359Sroberto */ 57954359Sroberto code = lastcode; 58054359Sroberto for (i = 0; i < NCHUCHARS/2; i++) { 58154359Sroberto *code++ = chuc->codechars[i] & 0xf; 58254359Sroberto *code++ = (chuc->codechars[i] >> 4) & 0xf; 58354359Sroberto } 58454359Sroberto 58554359Sroberto /* 58654359Sroberto * If the first nibble isn't a 6, we're up the creek 58754359Sroberto */ 58854359Sroberto code = lastcode; 58954359Sroberto if (*code++ != 6) { 59054359Sroberto (void) printf("Bad format, no 6 at start\n"); 59154359Sroberto return; 59254359Sroberto } 59354359Sroberto 59454359Sroberto /* 59554359Sroberto * Collect the day, the hour, the minute and the second. 59654359Sroberto */ 59754359Sroberto day = *code++; 59854359Sroberto day = MULBY10(day) + *code++; 59954359Sroberto day = MULBY10(day) + *code++; 60054359Sroberto hour = *code++; 60154359Sroberto hour = MULBY10(hour) + *code++; 60254359Sroberto minute = *code++; 60354359Sroberto minute = MULBY10(minute) + *code++; 60454359Sroberto second = *code++; 60554359Sroberto second = MULBY10(second) + *code++; 60654359Sroberto 60754359Sroberto /* 60854359Sroberto * Sanity check the day and time. Note that this 60954359Sroberto * only occurs on the 31st through the 39th second 61054359Sroberto * of the minute. 61154359Sroberto */ 61254359Sroberto if (day < 1 || day > 366 61354359Sroberto || hour > 23 || minute > 59 61454359Sroberto || second < 31 || second > 39) { 61554359Sroberto (void) printf("Failed date sanity check: %d %d %d %d\n", 61654359Sroberto day, hour, minute, second); 61754359Sroberto return; 61854359Sroberto } 61954359Sroberto 62054359Sroberto /* 62154359Sroberto * Compute seconds into the year. 62254359Sroberto */ 62354359Sroberto tmp = (u_long)(MULBY24((day-1)) + hour); /* hours */ 62454359Sroberto tmp = MULBY60(tmp) + (u_long)minute; /* minutes */ 62554359Sroberto tmp = MULBY60(tmp) + (u_long)second; /* seconds */ 62654359Sroberto 62754359Sroberto /* 62854359Sroberto * Now the fun begins. We demand that the received time code 62954359Sroberto * be within CLOCK_WAYTOOBIG of the receive timestamp, but 63054359Sroberto * there is uncertainty about the year the timestamp is in. 63154359Sroberto * Use the current year start for the first check, this should 63254359Sroberto * work most of the time. 63354359Sroberto */ 63454359Sroberto date_ui = tmp + yearstart; 63554359Sroberto if (date_ui < (rtime->l_ui + CLOCK_WAYTOOBIG) 63654359Sroberto && date_ui > (rtime->l_ui - CLOCK_WAYTOOBIG)) 63754359Sroberto goto codeokay; /* looks good */ 63854359Sroberto 63954359Sroberto /* 64054359Sroberto * Trouble. Next check is to see if the year rolled over and, if 64154359Sroberto * so, try again with the new year's start. 64254359Sroberto */ 64354359Sroberto date_ui = calyearstart(rtime->l_ui); 64454359Sroberto if (date_ui != yearstart) { 64554359Sroberto yearstart = date_ui; 64654359Sroberto date_ui += tmp; 64754359Sroberto (void) printf("time %u, code %u, difference %d\n", 64854359Sroberto date_ui, rtime->l_ui, (long)date_ui-(long)rtime->l_ui); 64954359Sroberto if (date_ui < (rtime->l_ui + CLOCK_WAYTOOBIG) 65054359Sroberto && date_ui > (rtime->l_ui - CLOCK_WAYTOOBIG)) 65154359Sroberto goto codeokay; /* okay this time */ 65254359Sroberto } 65354359Sroberto 65454359Sroberto ts.l_uf = 0; 65554359Sroberto ts.l_ui = yearstart; 65654359Sroberto printf("yearstart %s\n", prettydate(&ts)); 65754359Sroberto printf("received %s\n", prettydate(rtime)); 65854359Sroberto ts.l_ui = date_ui; 65954359Sroberto printf("date_ui %s\n", prettydate(&ts)); 66054359Sroberto 66154359Sroberto /* 66254359Sroberto * Here we know the year start matches the current system 66354359Sroberto * time. One remaining possibility is that the time code 66454359Sroberto * is in the year previous to that of the system time. This 66554359Sroberto * is only worth checking if the receive timestamp is less 66654359Sroberto * than CLOCK_WAYTOOBIG seconds into the new year. 66754359Sroberto */ 66854359Sroberto if ((rtime->l_ui - yearstart) < CLOCK_WAYTOOBIG) { 66954359Sroberto date_ui = tmp + calyearstart(yearstart - CLOCK_WAYTOOBIG); 67054359Sroberto if ((rtime->l_ui - date_ui) < CLOCK_WAYTOOBIG) 67154359Sroberto goto codeokay; 67254359Sroberto } 67354359Sroberto 67454359Sroberto /* 67554359Sroberto * One last possibility is that the time stamp is in the year 67654359Sroberto * following the year the system is in. Try this one before 67754359Sroberto * giving up. 67854359Sroberto */ 67954359Sroberto date_ui = tmp + calyearstart(yearstart + (400*24*60*60)); /* 400 days */ 68054359Sroberto if ((date_ui - rtime->l_ui) >= CLOCK_WAYTOOBIG) { 68154359Sroberto printf("Date hopelessly off\n"); 68254359Sroberto return; /* hopeless, let it sync to other peers */ 68354359Sroberto } 68454359Sroberto 68554359Sroberto codeokay: 68654359Sroberto reftime = date_ui; 68754359Sroberto /* 68854359Sroberto * We've now got the integral seconds part of the time code (we hope). 68954359Sroberto * The fractional part comes from the table. We next compute 69054359Sroberto * the offsets for each character. 69154359Sroberto */ 69254359Sroberto for (i = 0; i < NCHUCHARS; i++) { 69354359Sroberto register u_long tmp2; 69454359Sroberto 69554359Sroberto off[i].l_ui = date_ui; 69654359Sroberto off[i].l_uf = chutable[i]; 69754359Sroberto tmp = chuc->codetimes[i].tv_sec + JAN_1970; 69854359Sroberto TVUTOTSF(chuc->codetimes[i].tv_usec, tmp2); 69954359Sroberto M_SUB(off[i].l_ui, off[i].l_uf, tmp, tmp2); 70054359Sroberto } 70154359Sroberto 70254359Sroberto /* 70354359Sroberto * Here is a *big* problem. What one would normally 70454359Sroberto * do here on a machine with lots of clock bits (say 70554359Sroberto * a Vax or the gizmo board) is pick the most positive 70654359Sroberto * offset and the estimate, since this is the one that 70754359Sroberto * is most likely suffered the smallest interrupt delay. 70854359Sroberto * The trouble is that the low order clock bit on an IBM 70954359Sroberto * RT, which is the machine I had in mind when doing this, 71054359Sroberto * ticks at just under the millisecond mark. This isn't 71154359Sroberto * precise enough. What we can do to improve this is to 71254359Sroberto * average all 10 samples and rely on the second level 71354359Sroberto * filtering to pick the least delayed estimate. Trouble 71454359Sroberto * is, this means we have to divide a 64 bit fixed point 71554359Sroberto * number by 10, a procedure which really sucks. Oh, well. 71654359Sroberto * First compute the sum. 71754359Sroberto */ 71854359Sroberto date_ui = 0; 71954359Sroberto tmp = 0; 72054359Sroberto for (i = 0; i < NCHUCHARS; i++) 72154359Sroberto M_ADD(date_ui, tmp, off[i].l_ui, off[i].l_uf); 72254359Sroberto if (M_ISNEG(date_ui, tmp)) 72354359Sroberto isneg = 1; 72454359Sroberto else 72554359Sroberto isneg = 0; 72654359Sroberto 72754359Sroberto /* 72854359Sroberto * Here is a multiply-by-0.1 optimization that should apply 72954359Sroberto * just about everywhere. If the magnitude of the sum 73054359Sroberto * is less than 9 we don't have to worry about overflow 73154359Sroberto * out of a 64 bit product, even after rounding. 73254359Sroberto */ 73354359Sroberto if (date_ui < 9 || date_ui > 0xfffffff7) { 73454359Sroberto register u_long prod_ui; 73554359Sroberto register u_long prod_uf; 73654359Sroberto 73754359Sroberto prod_ui = prod_uf = 0; 73854359Sroberto /* 73954359Sroberto * This code knows the low order bit in 0.1 is zero 74054359Sroberto */ 74154359Sroberto for (i = 1; i < NZPOBITS; i++) { 74254359Sroberto M_LSHIFT(date_ui, tmp); 74354359Sroberto if (ZEROPTONE & (1<<i)) 74454359Sroberto M_ADD(prod_ui, prod_uf, date_ui, tmp); 74554359Sroberto } 74654359Sroberto 74754359Sroberto /* 74854359Sroberto * Done, round it correctly. Prod_ui contains the 74954359Sroberto * fraction. 75054359Sroberto */ 75154359Sroberto if (prod_uf & 0x80000000) 75254359Sroberto prod_ui++; 75354359Sroberto if (isneg) 75454359Sroberto date_ui = 0xffffffff; 75554359Sroberto else 75654359Sroberto date_ui = 0; 75754359Sroberto tmp = prod_ui; 75854359Sroberto /* 75954359Sroberto * date_ui is integral part, tmp is fraction. 76054359Sroberto */ 76154359Sroberto } else { 76254359Sroberto register u_long prod_ovr; 76354359Sroberto register u_long prod_ui; 76454359Sroberto register u_long prod_uf; 76554359Sroberto register u_long highbits; 76654359Sroberto 76754359Sroberto prod_ovr = prod_ui = prod_uf = 0; 76854359Sroberto if (isneg) 76954359Sroberto highbits = 0xffffffff; /* sign extend */ 77054359Sroberto else 77154359Sroberto highbits = 0; 77254359Sroberto /* 77354359Sroberto * This code knows the low order bit in 0.1 is zero 77454359Sroberto */ 77554359Sroberto for (i = 1; i < NZPOBITS; i++) { 77654359Sroberto M_LSHIFT3(highbits, date_ui, tmp); 77754359Sroberto if (ZEROPTONE & (1<<i)) 77854359Sroberto M_ADD3(prod_ovr, prod_uf, prod_ui, 77954359Sroberto highbits, date_ui, tmp); 78054359Sroberto } 78154359Sroberto 78254359Sroberto if (prod_uf & 0x80000000) 78354359Sroberto M_ADDUF(prod_ovr, prod_ui, (u_long)1); 78454359Sroberto date_ui = prod_ovr; 78554359Sroberto tmp = prod_ui; 78654359Sroberto } 78754359Sroberto 78854359Sroberto /* 78954359Sroberto * At this point we have the mean offset, with the integral 79054359Sroberto * part in date_ui and the fractional part in tmp. Store 79154359Sroberto * it in the structure. 79254359Sroberto */ 79354359Sroberto /* 79454359Sroberto * Add in fudge factor. 79554359Sroberto */ 79654359Sroberto M_ADD(date_ui, tmp, offset_fudge.l_ui, offset_fudge.l_uf); 79754359Sroberto 79854359Sroberto /* 79954359Sroberto * Find the minimun and maximum offset 80054359Sroberto */ 80154359Sroberto imin = imax = 0; 80254359Sroberto for (i = 1; i < NCHUCHARS; i++) { 80354359Sroberto if (L_ISGEQ(&off[i], &off[imax])) { 80454359Sroberto imax = i; 80554359Sroberto } else if (L_ISGEQ(&off[imin], &off[i])) { 80654359Sroberto imin = i; 80754359Sroberto } 80854359Sroberto } 80954359Sroberto 81054359Sroberto L_ADD(&off[imin], &offset_fudge); 81154359Sroberto if (imin != imax) 81254359Sroberto L_ADD(&off[imax], &offset_fudge); 81354359Sroberto (void) printf("mean %s, min %s, max %s\n", 81454359Sroberto mfptoa(date_ui, tmp, 8), lfptoa(&off[imin], 8), 81554359Sroberto lfptoa(&off[imax], 8)); 81654359Sroberto} 817