817 lines
19 KiB
C
817 lines
19 KiB
C
/* chutest.c,v 3.1 1993/07/06 01:05:21 jbj Exp
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* chutest - test the CHU clock
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*/
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#include <stdio.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <sys/ioctl.h>
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#include <sys/time.h>
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#include <sys/file.h>
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#include <sgtty.h>
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#include "../include/ntp_fp.h"
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#include "../include/ntp.h"
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#include "../include/ntp_unixtime.h"
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#ifdef CHULDISC
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#ifdef STREAM
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# ifdef HAVE_SYS_CHUDEFS_H
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#include <sys/chudefs.h>
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#endif
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#include <stropts.h>
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#endif
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#endif
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#ifdef CHULDISC
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# ifdef HAVE_SYS_CHUDEFS_H
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#include <sys/chudefs.h>
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#endif
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#endif
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#ifndef CHULDISC
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#ifndef STREAM
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#define NCHUCHARS (10)
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struct chucode {
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u_char codechars[NCHUCHARS]; /* code characters */
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u_char ncodechars; /* number of code characters */
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u_char chustatus; /* not used currently */
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struct timeval codetimes[NCHUCHARS]; /* arrival times */
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};
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#endif
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#endif
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#define STREQ(a, b) (*(a) == *(b) && strcmp((a), (b)) == 0)
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char *progname;
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int debug;
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int dofilter = 0; /* set to 1 when we should run filter algorithm */
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int showtimes = 0; /* set to 1 when we should show char arrival times */
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int doprocess = 0; /* set to 1 when we do processing analogous to driver */
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#ifdef CHULDISC
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int usechuldisc = 0; /* set to 1 when CHU line discipline should be used */
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#endif
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#ifdef STREAM
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int usechuldisc = 0; /* set to 1 when CHU line discipline should be used */
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#endif
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struct timeval lasttv;
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struct chucode chudata;
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extern u_long ustotslo[];
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extern u_long ustotsmid[];
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extern u_long ustotshi[];
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/*
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* main - parse arguments and handle options
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*/
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int
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main(
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int argc,
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char *argv[]
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)
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{
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int c;
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int errflg = 0;
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extern int ntp_optind;
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extern char *ntp_optarg;
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void init_chu();
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progname = argv[0];
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while ((c = ntp_getopt(argc, argv, "cdfpt")) != EOF)
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switch (c) {
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case 'c':
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#ifdef STREAM
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usechuldisc = 1;
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break;
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#endif
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#ifdef CHULDISC
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usechuldisc = 1;
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break;
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#endif
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#ifndef STREAM
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#ifndef CHULDISC
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(void) fprintf(stderr,
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"%s: CHU line discipline not available on this machine\n",
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progname);
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exit(2);
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#endif
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#endif
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case 'd':
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++debug;
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break;
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case 'f':
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dofilter = 1;
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break;
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case 'p':
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doprocess = 1;
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case 't':
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showtimes = 1;
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break;
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default:
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errflg++;
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break;
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}
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if (errflg || ntp_optind+1 != argc) {
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#ifdef STREAM
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(void) fprintf(stderr, "usage: %s [-dft] tty_device\n",
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progname);
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#endif
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#ifdef CHULDISC
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(void) fprintf(stderr, "usage: %s [-dft] tty_device\n",
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progname);
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#endif
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#ifndef STREAM
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#ifndef CHULDISC
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(void) fprintf(stderr, "usage: %s [-cdft] tty_device\n",
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progname);
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#endif
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#endif
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exit(2);
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}
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(void) gettimeofday(&lasttv, (struct timezone *)0);
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c = openterm(argv[ntp_optind]);
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init_chu();
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#ifdef STREAM
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if (usechuldisc)
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process_ldisc(c);
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else
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#endif
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#ifdef CHULDISC
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if (usechuldisc)
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process_ldisc(c);
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else
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#endif
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process_raw(c);
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/*NOTREACHED*/
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}
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/*
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* openterm - open a port to the CHU clock
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*/
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int
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openterm(
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char *dev
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)
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{
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int s;
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struct sgttyb ttyb;
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if (debug)
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(void) fprintf(stderr, "Doing open...");
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if ((s = open(dev, O_RDONLY, 0777)) < 0)
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error("open(%s)", dev, "");
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if (debug)
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(void) fprintf(stderr, "open okay\n");
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if (debug)
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(void) fprintf(stderr, "Setting exclusive use...");
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if (ioctl(s, TIOCEXCL, (char *)0) < 0)
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error("ioctl(TIOCEXCL)", "", "");
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if (debug)
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(void) fprintf(stderr, "done\n");
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ttyb.sg_ispeed = ttyb.sg_ospeed = B300;
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ttyb.sg_erase = ttyb.sg_kill = 0;
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ttyb.sg_flags = EVENP|ODDP|RAW;
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if (debug)
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(void) fprintf(stderr, "Setting baud rate et al...");
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if (ioctl(s, TIOCSETP, (char *)&ttyb) < 0)
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error("ioctl(TIOCSETP, raw)", "", "");
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if (debug)
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(void) fprintf(stderr, "done\n");
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#ifdef CHULDISC
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if (usechuldisc) {
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int ldisc;
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if (debug)
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(void) fprintf(stderr, "Switching to CHU ldisc...");
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ldisc = CHULDISC;
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if (ioctl(s, TIOCSETD, (char *)&ldisc) < 0)
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error("ioctl(TIOCSETD, CHULDISC)", "", "");
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if (debug)
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(void) fprintf(stderr, "okay\n");
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}
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#endif
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#ifdef STREAM
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if (usechuldisc) {
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if (debug)
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(void) fprintf(stderr, "Poping off streams...");
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while (ioctl(s, I_POP, 0) >=0) ;
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if (debug)
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(void) fprintf(stderr, "okay\n");
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if (debug)
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(void) fprintf(stderr, "Pushing CHU stream...");
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if (ioctl(s, I_PUSH, "chu") < 0)
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error("ioctl(I_PUSH, \"chu\")", "", "");
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if (debug)
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(void) fprintf(stderr, "okay\n");
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}
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#endif
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return s;
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}
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/*
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* process_raw - process characters in raw mode
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*/
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int
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process_raw(
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int s
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)
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{
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u_char c;
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int n;
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struct timeval tv;
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struct timeval difftv;
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while ((n = read(s, &c, sizeof(char))) > 0) {
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(void) gettimeofday(&tv, (struct timezone *)0);
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if (dofilter)
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raw_filter((unsigned int)c, &tv);
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else {
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difftv.tv_sec = tv.tv_sec - lasttv.tv_sec;
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difftv.tv_usec = tv.tv_usec - lasttv.tv_usec;
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if (difftv.tv_usec < 0) {
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difftv.tv_sec--;
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difftv.tv_usec += 1000000;
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}
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(void) printf("%02x\t%lu.%06lu\t%lu.%06lu\n",
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c, tv.tv_sec, tv.tv_usec, difftv.tv_sec,
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difftv.tv_usec);
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lasttv = tv;
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}
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}
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if (n == 0) {
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(void) fprintf(stderr, "%s: zero returned on read\n", progname);
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exit(1);
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} else
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error("read()", "", "");
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}
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/*
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* raw_filter - run the line discipline filter over raw data
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*/
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int
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raw_filter(
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unsigned int c,
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struct timeval *tv
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)
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{
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static struct timeval diffs[10] = { 0 };
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struct timeval diff;
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l_fp ts;
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void chufilter();
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if ((c & 0xf) > 9 || ((c>>4)&0xf) > 9) {
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if (debug)
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(void) fprintf(stderr,
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"character %02x failed BCD test\n");
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chudata.ncodechars = 0;
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return;
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}
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if (chudata.ncodechars > 0) {
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diff.tv_sec = tv->tv_sec
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- chudata.codetimes[chudata.ncodechars].tv_sec;
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diff.tv_usec = tv->tv_usec
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- chudata.codetimes[chudata.ncodechars].tv_usec;
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if (diff.tv_usec < 0) {
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diff.tv_sec--;
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diff.tv_usec += 1000000;
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} /*
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if (diff.tv_sec != 0 || diff.tv_usec > 900000) {
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if (debug)
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(void) fprintf(stderr,
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"character %02x failed time test\n");
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chudata.ncodechars = 0;
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return;
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} */
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}
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chudata.codechars[chudata.ncodechars] = c;
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chudata.codetimes[chudata.ncodechars] = *tv;
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if (chudata.ncodechars > 0)
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diffs[chudata.ncodechars] = diff;
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if (++chudata.ncodechars == 10) {
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if (doprocess) {
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TVTOTS(&chudata.codetimes[NCHUCHARS-1], &ts);
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ts.l_ui += JAN_1970;
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chufilter(&chudata, &chudata.codetimes[NCHUCHARS-1]);
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} else {
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register int i;
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for (i = 0; i < chudata.ncodechars; i++) {
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(void) printf("%x%x\t%lu.%06lu\t%lu.%06lu\n",
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chudata.codechars[i] & 0xf,
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(chudata.codechars[i] >>4 ) & 0xf,
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chudata.codetimes[i].tv_sec,
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chudata.codetimes[i].tv_usec,
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diffs[i].tv_sec, diffs[i].tv_usec);
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}
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}
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chudata.ncodechars = 0;
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}
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}
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/* #ifdef CHULDISC*/
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/*
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* process_ldisc - process line discipline
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*/
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int
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process_ldisc(
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int s
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)
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{
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struct chucode chu;
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int n;
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register int i;
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struct timeval diff;
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l_fp ts;
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void chufilter();
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while ((n = read(s, (char *)&chu, sizeof chu)) > 0) {
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if (n != sizeof chu) {
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(void) fprintf(stderr, "Expected %d, got %d\n",
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sizeof chu, n);
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continue;
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}
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if (doprocess) {
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TVTOTS(&chu.codetimes[NCHUCHARS-1], &ts);
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ts.l_ui += JAN_1970;
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chufilter(&chu, &ts);
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} else {
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for (i = 0; i < NCHUCHARS; i++) {
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if (i == 0)
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diff.tv_sec = diff.tv_usec = 0;
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else {
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diff.tv_sec = chu.codetimes[i].tv_sec
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- chu.codetimes[i-1].tv_sec;
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diff.tv_usec = chu.codetimes[i].tv_usec
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- chu.codetimes[i-1].tv_usec;
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if (diff.tv_usec < 0) {
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diff.tv_sec--;
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diff.tv_usec += 1000000;
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}
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}
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(void) printf("%x%x\t%lu.%06lu\t%lu.%06lu\n",
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chu.codechars[i] & 0xf, (chu.codechars[i]>>4)&0xf,
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chu.codetimes[i].tv_sec, chu.codetimes[i].tv_usec,
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diff.tv_sec, diff.tv_usec);
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}
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}
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}
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if (n == 0) {
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(void) fprintf(stderr, "%s: zero returned on read\n", progname);
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exit(1);
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} else
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error("read()", "", "");
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}
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/*#endif*/
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/*
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* error - print an error message
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*/
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void
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error(
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char *fmt,
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char *s1,
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char *s2
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)
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{
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(void) fprintf(stderr, "%s: ", progname);
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(void) fprintf(stderr, fmt, s1, s2);
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(void) fprintf(stderr, ": ");
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perror("");
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exit(1);
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}
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/*
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* Definitions
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*/
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#define MAXUNITS 4 /* maximum number of CHU units permitted */
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#define CHUDEV "/dev/chu%d" /* device we open. %d is unit number */
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#define NCHUCODES 9 /* expect 9 CHU codes per minute */
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/*
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* When CHU is operating optimally we want the primary clock distance
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* to come out at 300 ms. Thus, peer.distance in the CHU peer structure
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* is set to 290 ms and we compute delays which are at least 10 ms long.
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* The following are 290 ms and 10 ms expressed in u_fp format
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*/
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#define CHUDISTANCE 0x00004a3d
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#define CHUBASEDELAY 0x0000028f
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/*
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* To compute a quality for the estimate (a pseudo delay) we add a
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* fixed 10 ms for each missing code in the minute and add to this
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* the sum of the differences between the remaining offsets and the
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* estimated sample offset.
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*/
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#define CHUDELAYPENALTY 0x0000028f
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/*
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* Other constant stuff
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*/
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#define CHUPRECISION (-9) /* what the heck */
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#define CHUREFID "CHU\0"
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/*
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* Default fudge factors
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*/
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#define DEFPROPDELAY 0x00624dd3 /* 0.0015 seconds, 1.5 ms */
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#define DEFFILTFUDGE 0x000d1b71 /* 0.0002 seconds, 200 us */
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/*
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* Hacks to avoid excercising the multiplier. I have no pride.
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*/
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#define MULBY10(x) (((x)<<3) + ((x)<<1))
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#define MULBY60(x) (((x)<<6) - ((x)<<2)) /* watch overflow */
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#define MULBY24(x) (((x)<<4) + ((x)<<3))
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/*
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* Constants for use when multiplying by 0.1. ZEROPTONE is 0.1
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* as an l_fp fraction, NZPOBITS is the number of significant bits
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* in ZEROPTONE.
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*/
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#define ZEROPTONE 0x1999999a
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#define NZPOBITS 29
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/*
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* The CHU table. This gives the expected time of arrival of each
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* character after the on-time second and is computed as follows:
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* The CHU time code is sent at 300 bps. Your average UART will
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* synchronize at the edge of the start bit and will consider the
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* character complete at the center of the first stop bit, i.e.
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* 0.031667 ms later. Thus the expected time of each interrupt
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* is the start bit time plus 0.031667 seconds. These times are
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* in chutable[]. To this we add such things as propagation delay
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* and delay fudge factor.
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*/
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#define CHARDELAY 0x081b4e80
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static u_long chutable[NCHUCHARS] = {
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0x2147ae14 + CHARDELAY, /* 0.130 (exactly) */
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0x2ac08312 + CHARDELAY, /* 0.167 (exactly) */
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0x34395810 + CHARDELAY, /* 0.204 (exactly) */
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0x3db22d0e + CHARDELAY, /* 0.241 (exactly) */
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0x472b020c + CHARDELAY, /* 0.278 (exactly) */
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0x50a3d70a + CHARDELAY, /* 0.315 (exactly) */
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0x5a1cac08 + CHARDELAY, /* 0.352 (exactly) */
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0x63958106 + CHARDELAY, /* 0.389 (exactly) */
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0x6d0e5604 + CHARDELAY, /* 0.426 (exactly) */
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0x76872b02 + CHARDELAY, /* 0.463 (exactly) */
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};
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/*
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* Keep the fudge factors separately so they can be set even
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* when no clock is configured.
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*/
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static l_fp propagation_delay;
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static l_fp fudgefactor;
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static l_fp offset_fudge;
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/*
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* We keep track of the start of the year, watching for changes.
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* We also keep track of whether the year is a leap year or not.
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* All because stupid CHU doesn't include the year in the time code.
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*/
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static u_long yearstart;
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/*
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* Imported from the timer module
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*/
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extern u_long current_time;
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extern struct event timerqueue[];
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/*
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* Time conversion tables imported from the library
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*/
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extern u_long ustotslo[];
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extern u_long ustotsmid[];
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extern u_long ustotshi[];
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/*
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* init_chu - initialize internal chu driver data
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*/
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void
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init_chu(void)
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{
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/*
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* Initialize fudge factors to default.
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*/
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propagation_delay.l_ui = 0;
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propagation_delay.l_uf = DEFPROPDELAY;
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fudgefactor.l_ui = 0;
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fudgefactor.l_uf = DEFFILTFUDGE;
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offset_fudge = propagation_delay;
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L_ADD(&offset_fudge, &fudgefactor);
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yearstart = 0;
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}
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void
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chufilter(
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struct chucode *chuc,
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l_fp *rtime
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)
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{
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register int i;
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register u_long date_ui;
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register u_long tmp;
|
|
register u_char *code;
|
|
int isneg;
|
|
int imin;
|
|
int imax;
|
|
u_long reftime;
|
|
l_fp off[NCHUCHARS];
|
|
l_fp ts;
|
|
int day, hour, minute, second;
|
|
static u_char lastcode[NCHUCHARS];
|
|
extern u_long calyearstart();
|
|
extern char *mfptoa();
|
|
void chu_process();
|
|
extern char *prettydate();
|
|
|
|
/*
|
|
* We'll skip the checks made in the kernel, but assume they've
|
|
* been done. This means that all characters are BCD and
|
|
* the intercharacter spacing isn't unreasonable.
|
|
*/
|
|
|
|
/*
|
|
* print the code
|
|
*/
|
|
for (i = 0; i < NCHUCHARS; i++)
|
|
printf("%c%c", (chuc->codechars[i] & 0xf) + '0',
|
|
((chuc->codechars[i]>>4) & 0xf) + '0');
|
|
printf("\n");
|
|
|
|
/*
|
|
* Format check. Make sure the two halves match.
|
|
*/
|
|
for (i = 0; i < NCHUCHARS/2; i++)
|
|
if (chuc->codechars[i] != chuc->codechars[i+(NCHUCHARS/2)]) {
|
|
(void) printf("Bad format, halves don't match\n");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Break out the code into the BCD nibbles. Only need to fiddle
|
|
* with the first half since both are identical. Note the first
|
|
* BCD character is the low order nibble, the second the high order.
|
|
*/
|
|
code = lastcode;
|
|
for (i = 0; i < NCHUCHARS/2; i++) {
|
|
*code++ = chuc->codechars[i] & 0xf;
|
|
*code++ = (chuc->codechars[i] >> 4) & 0xf;
|
|
}
|
|
|
|
/*
|
|
* If the first nibble isn't a 6, we're up the creek
|
|
*/
|
|
code = lastcode;
|
|
if (*code++ != 6) {
|
|
(void) printf("Bad format, no 6 at start\n");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Collect the day, the hour, the minute and the second.
|
|
*/
|
|
day = *code++;
|
|
day = MULBY10(day) + *code++;
|
|
day = MULBY10(day) + *code++;
|
|
hour = *code++;
|
|
hour = MULBY10(hour) + *code++;
|
|
minute = *code++;
|
|
minute = MULBY10(minute) + *code++;
|
|
second = *code++;
|
|
second = MULBY10(second) + *code++;
|
|
|
|
/*
|
|
* Sanity check the day and time. Note that this
|
|
* only occurs on the 31st through the 39th second
|
|
* of the minute.
|
|
*/
|
|
if (day < 1 || day > 366
|
|
|| hour > 23 || minute > 59
|
|
|| second < 31 || second > 39) {
|
|
(void) printf("Failed date sanity check: %d %d %d %d\n",
|
|
day, hour, minute, second);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Compute seconds into the year.
|
|
*/
|
|
tmp = (u_long)(MULBY24((day-1)) + hour); /* hours */
|
|
tmp = MULBY60(tmp) + (u_long)minute; /* minutes */
|
|
tmp = MULBY60(tmp) + (u_long)second; /* seconds */
|
|
|
|
/*
|
|
* Now the fun begins. We demand that the received time code
|
|
* be within CLOCK_WAYTOOBIG of the receive timestamp, but
|
|
* there is uncertainty about the year the timestamp is in.
|
|
* Use the current year start for the first check, this should
|
|
* work most of the time.
|
|
*/
|
|
date_ui = tmp + yearstart;
|
|
if (date_ui < (rtime->l_ui + CLOCK_WAYTOOBIG)
|
|
&& date_ui > (rtime->l_ui - CLOCK_WAYTOOBIG))
|
|
goto codeokay; /* looks good */
|
|
|
|
/*
|
|
* Trouble. Next check is to see if the year rolled over and, if
|
|
* so, try again with the new year's start.
|
|
*/
|
|
date_ui = calyearstart(rtime->l_ui);
|
|
if (date_ui != yearstart) {
|
|
yearstart = date_ui;
|
|
date_ui += tmp;
|
|
(void) printf("time %u, code %u, difference %d\n",
|
|
date_ui, rtime->l_ui, (long)date_ui-(long)rtime->l_ui);
|
|
if (date_ui < (rtime->l_ui + CLOCK_WAYTOOBIG)
|
|
&& date_ui > (rtime->l_ui - CLOCK_WAYTOOBIG))
|
|
goto codeokay; /* okay this time */
|
|
}
|
|
|
|
ts.l_uf = 0;
|
|
ts.l_ui = yearstart;
|
|
printf("yearstart %s\n", prettydate(&ts));
|
|
printf("received %s\n", prettydate(rtime));
|
|
ts.l_ui = date_ui;
|
|
printf("date_ui %s\n", prettydate(&ts));
|
|
|
|
/*
|
|
* Here we know the year start matches the current system
|
|
* time. One remaining possibility is that the time code
|
|
* is in the year previous to that of the system time. This
|
|
* is only worth checking if the receive timestamp is less
|
|
* than CLOCK_WAYTOOBIG seconds into the new year.
|
|
*/
|
|
if ((rtime->l_ui - yearstart) < CLOCK_WAYTOOBIG) {
|
|
date_ui = tmp + calyearstart(yearstart - CLOCK_WAYTOOBIG);
|
|
if ((rtime->l_ui - date_ui) < CLOCK_WAYTOOBIG)
|
|
goto codeokay;
|
|
}
|
|
|
|
/*
|
|
* One last possibility is that the time stamp is in the year
|
|
* following the year the system is in. Try this one before
|
|
* giving up.
|
|
*/
|
|
date_ui = tmp + calyearstart(yearstart + (400*24*60*60)); /* 400 days */
|
|
if ((date_ui - rtime->l_ui) >= CLOCK_WAYTOOBIG) {
|
|
printf("Date hopelessly off\n");
|
|
return; /* hopeless, let it sync to other peers */
|
|
}
|
|
|
|
codeokay:
|
|
reftime = date_ui;
|
|
/*
|
|
* We've now got the integral seconds part of the time code (we hope).
|
|
* The fractional part comes from the table. We next compute
|
|
* the offsets for each character.
|
|
*/
|
|
for (i = 0; i < NCHUCHARS; i++) {
|
|
register u_long tmp2;
|
|
|
|
off[i].l_ui = date_ui;
|
|
off[i].l_uf = chutable[i];
|
|
tmp = chuc->codetimes[i].tv_sec + JAN_1970;
|
|
TVUTOTSF(chuc->codetimes[i].tv_usec, tmp2);
|
|
M_SUB(off[i].l_ui, off[i].l_uf, tmp, tmp2);
|
|
}
|
|
|
|
/*
|
|
* Here is a *big* problem. What one would normally
|
|
* do here on a machine with lots of clock bits (say
|
|
* a Vax or the gizmo board) is pick the most positive
|
|
* offset and the estimate, since this is the one that
|
|
* is most likely suffered the smallest interrupt delay.
|
|
* The trouble is that the low order clock bit on an IBM
|
|
* RT, which is the machine I had in mind when doing this,
|
|
* ticks at just under the millisecond mark. This isn't
|
|
* precise enough. What we can do to improve this is to
|
|
* average all 10 samples and rely on the second level
|
|
* filtering to pick the least delayed estimate. Trouble
|
|
* is, this means we have to divide a 64 bit fixed point
|
|
* number by 10, a procedure which really sucks. Oh, well.
|
|
* First compute the sum.
|
|
*/
|
|
date_ui = 0;
|
|
tmp = 0;
|
|
for (i = 0; i < NCHUCHARS; i++)
|
|
M_ADD(date_ui, tmp, off[i].l_ui, off[i].l_uf);
|
|
if (M_ISNEG(date_ui, tmp))
|
|
isneg = 1;
|
|
else
|
|
isneg = 0;
|
|
|
|
/*
|
|
* Here is a multiply-by-0.1 optimization that should apply
|
|
* just about everywhere. If the magnitude of the sum
|
|
* is less than 9 we don't have to worry about overflow
|
|
* out of a 64 bit product, even after rounding.
|
|
*/
|
|
if (date_ui < 9 || date_ui > 0xfffffff7) {
|
|
register u_long prod_ui;
|
|
register u_long prod_uf;
|
|
|
|
prod_ui = prod_uf = 0;
|
|
/*
|
|
* This code knows the low order bit in 0.1 is zero
|
|
*/
|
|
for (i = 1; i < NZPOBITS; i++) {
|
|
M_LSHIFT(date_ui, tmp);
|
|
if (ZEROPTONE & (1<<i))
|
|
M_ADD(prod_ui, prod_uf, date_ui, tmp);
|
|
}
|
|
|
|
/*
|
|
* Done, round it correctly. Prod_ui contains the
|
|
* fraction.
|
|
*/
|
|
if (prod_uf & 0x80000000)
|
|
prod_ui++;
|
|
if (isneg)
|
|
date_ui = 0xffffffff;
|
|
else
|
|
date_ui = 0;
|
|
tmp = prod_ui;
|
|
/*
|
|
* date_ui is integral part, tmp is fraction.
|
|
*/
|
|
} else {
|
|
register u_long prod_ovr;
|
|
register u_long prod_ui;
|
|
register u_long prod_uf;
|
|
register u_long highbits;
|
|
|
|
prod_ovr = prod_ui = prod_uf = 0;
|
|
if (isneg)
|
|
highbits = 0xffffffff; /* sign extend */
|
|
else
|
|
highbits = 0;
|
|
/*
|
|
* This code knows the low order bit in 0.1 is zero
|
|
*/
|
|
for (i = 1; i < NZPOBITS; i++) {
|
|
M_LSHIFT3(highbits, date_ui, tmp);
|
|
if (ZEROPTONE & (1<<i))
|
|
M_ADD3(prod_ovr, prod_uf, prod_ui,
|
|
highbits, date_ui, tmp);
|
|
}
|
|
|
|
if (prod_uf & 0x80000000)
|
|
M_ADDUF(prod_ovr, prod_ui, (u_long)1);
|
|
date_ui = prod_ovr;
|
|
tmp = prod_ui;
|
|
}
|
|
|
|
/*
|
|
* At this point we have the mean offset, with the integral
|
|
* part in date_ui and the fractional part in tmp. Store
|
|
* it in the structure.
|
|
*/
|
|
/*
|
|
* Add in fudge factor.
|
|
*/
|
|
M_ADD(date_ui, tmp, offset_fudge.l_ui, offset_fudge.l_uf);
|
|
|
|
/*
|
|
* Find the minimun and maximum offset
|
|
*/
|
|
imin = imax = 0;
|
|
for (i = 1; i < NCHUCHARS; i++) {
|
|
if (L_ISGEQ(&off[i], &off[imax])) {
|
|
imax = i;
|
|
} else if (L_ISGEQ(&off[imin], &off[i])) {
|
|
imin = i;
|
|
}
|
|
}
|
|
|
|
L_ADD(&off[imin], &offset_fudge);
|
|
if (imin != imax)
|
|
L_ADD(&off[imax], &offset_fudge);
|
|
(void) printf("mean %s, min %s, max %s\n",
|
|
mfptoa(date_ui, tmp, 8), lfptoa(&off[imin], 8),
|
|
lfptoa(&off[imax], 8));
|
|
}
|