Virgin import of ntpd 4.0.98f

1 files changed, 544 insertions, 0 deletions

diff --git a/contrib/ntp/clockstuff/propdelay.c b/contrib/ntp/clockstuff/propdelay.c
new file mode 100644
index 0000000..3ce571c
--- /dev/null
+++ b/contrib/ntp/clockstuff/propdelay.c
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+/* propdelay.c,v 3.1 1993/07/06 01:05:24 jbj Exp
+ * propdelay - compute propagation delays
+ *
+ * cc -o propdelay propdelay.c -lm
+ *
+ * "Time and Frequency Users' Manual", NBS Technical Note 695 (1977).
+ */
+
+/*
+ * This can be used to get a rough idea of the HF propagation delay
+ * between two points (usually between you and the radio station).
+ * The usage is
+ *
+ * propdelay latitudeA longitudeA latitudeB longitudeB
+ *
+ * where points A and B are the locations in question.  You obviously
+ * need to know the latitude and longitude of each of the places.
+ * The program expects the latitude to be preceded by an 'n' or 's'
+ * and the longitude to be preceded by an 'e' or 'w'.  It understands
+ * either decimal degrees or degrees:minutes:seconds.  Thus to compute
+ * the delay between the WWVH (21:59:26N, 159:46:00W) and WWV (40:40:49N,
+ * 105:02:27W) you could use:
+ *
+ * propdelay n21:59:26 w159:46 n40:40:49 w105:02:27
+ *
+ * By default it prints out a summer (F2 average virtual height 350 km) and
+ * winter (F2 average virtual height 250 km) number.  The results will be
+ * quite approximate but are about as good as you can do with HF time anyway.
+ * You might pick a number between the values to use, or use the summer
+ * value in the summer and switch to the winter value when the static
+ * above 10 MHz starts to drop off in the fall.  You can also use the
+ * -h switch if you want to specify your own virtual height.
+ *
+ * You can also do a
+ *
+ * propdelay -W n45:17:47 w75:45:22
+ *
+ * to find the propagation delays to WWV and WWVH (from CHU in this
+ * case), a
+ *
+ * propdelay -C n40:40:49 w105:02:27
+ *
+ * to find the delays to CHU, and a
+ *
+ * propdelay -G n52:03:17 w98:34:18
+ *
+ * to find delays to GOES via each of the three satellites.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "ntp_stdlib.h"
+
+extern	double	sin	(double);
+extern	double	cos	(double);
+extern	double	acos	(double);
+extern	double	tan	(double);
+extern	double	atan	(double);
+extern	double	sqrt	(double);
+
+#define	STREQ(a, b)	(*(a) == *(b) && strcmp((a), (b)) == 0)
+
+/*
+ * Program constants
+ */
+#define	EARTHRADIUS	(6370.0)	/* raduis of earth (km) */
+#define	LIGHTSPEED	(299800.0)	/* speed of light, km/s */
+#define	PI		(3.1415926536)
+#define	RADPERDEG	(PI/180.0)	/* radians per degree */
+#define MILE		(1.609344)      /* km in a mile */
+
+#define	SUMMERHEIGHT	(350.0)		/* summer height in km */
+#define	WINTERHEIGHT	(250.0)		/* winter height in km */
+
+#define SATHEIGHT	(6.6110 * 6378.0) /* geosync satellite height in km
+					     from centre of earth */
+
+#define WWVLAT  "n40:40:49"
+#define WWVLONG "w105:02:27"
+
+#define WWVHLAT  "n21:59:26"
+#define WWVHLONG "w159:46:00"
+
+#define CHULAT	"n45:17:47"
+#define	CHULONG	"w75:45:22"
+
+#define GOES_UP_LAT  "n37:52:00"
+#define GOES_UP_LONG "w75:27:00"
+#define GOES_EAST_LONG "w75:00:00"
+#define GOES_STBY_LONG "w105:00:00"
+#define GOES_WEST_LONG "w135:00:00"
+#define GOES_SAT_LAT "n00:00:00"
+
+char *wwvlat = WWVLAT;
+char *wwvlong = WWVLONG;
+
+char *wwvhlat = WWVHLAT;
+char *wwvhlong = WWVHLONG;
+
+char *chulat = CHULAT;
+char *chulong = CHULONG;
+
+char *goes_up_lat = GOES_UP_LAT;
+char *goes_up_long = GOES_UP_LONG;
+char *goes_east_long = GOES_EAST_LONG;
+char *goes_stby_long = GOES_STBY_LONG;
+char *goes_west_long = GOES_WEST_LONG;
+char *goes_sat_lat = GOES_SAT_LAT;
+
+int hflag = 0;
+int Wflag = 0;
+int Cflag = 0;
+int Gflag = 0;
+int height;
+
+char *progname;
+int debug;
+
+static	void	doit		(double, double, double, double, double, char *);
+static	double	latlong		(char *, int);
+static	double	greatcircle	(double, double, double, double);
+static	double	waveangle	(double, double, int);
+static	double	propdelay	(double, double, int);
+static	int	finddelay	(double, double, double, double, double, double *);
+static	void	satdoit		(double, double, double, double, double, double, char *);
+static	void	satfinddelay	(double, double, double, double, double *);
+static	double	satpropdelay	(double);
+
+/*
+ * main - parse arguments and handle options
+ */
+int
+main(
+	int argc,
+	char *argv[]
+	)
+{
+	int c;
+	int errflg = 0;
+	double lat1, long1;
+	double lat2, long2;
+	double lat3, long3;
+
+	progname = argv[0];
+	while ((c = ntp_getopt(argc, argv, "dh:CWG")) != EOF)
+	    switch (c) {
+		case 'd':
+		    ++debug;
+		    break;
+		case 'h':
+		    hflag++;
+		    height = atof(ntp_optarg);
+		    if (height <= 0.0) {
+			    (void) fprintf(stderr, "height %s unlikely\n",
+					   ntp_optarg);
+			    errflg++;
+		    }
+		    break;
+		case 'C':
+		    Cflag++;
+		    break;
+		case 'W':
+		    Wflag++;
+		    break;
+		case 'G':
+		    Gflag++;
+		    break;
+		default:
+		    errflg++;
+		    break;
+	    }
+	if (errflg || (!(Cflag || Wflag || Gflag) && ntp_optind+4 != argc) || 
+	    ((Cflag || Wflag || Gflag) && ntp_optind+2 != argc)) {
+		(void) fprintf(stderr,
+			       "usage: %s [-d] [-h height] lat1 long1 lat2 long2\n",
+			       progname);
+		(void) fprintf(stderr," - or -\n");
+		(void) fprintf(stderr,
+			       "usage: %s -CWG [-d] lat long\n",
+			       progname);
+		exit(2);
+	}
+
+		   
+	if (!(Cflag || Wflag || Gflag)) {
+		lat1 = latlong(argv[ntp_optind], 1);
+		long1 = latlong(argv[ntp_optind + 1], 0);
+		lat2 = latlong(argv[ntp_optind + 2], 1);
+		long2 = latlong(argv[ntp_optind + 3], 0);
+		if (hflag) {
+			doit(lat1, long1, lat2, long2, height, "");
+		} else {
+			doit(lat1, long1, lat2, long2, (double)SUMMERHEIGHT,
+			     "summer propagation, ");
+			doit(lat1, long1, lat2, long2, (double)WINTERHEIGHT,
+			     "winter propagation, ");
+		}
+	} else if (Wflag) {
+		/*
+		 * Compute delay from WWV
+		 */
+		lat1 = latlong(argv[ntp_optind], 1);
+		long1 = latlong(argv[ntp_optind + 1], 0);
+		lat2 = latlong(wwvlat, 1);
+		long2 = latlong(wwvlong, 0);
+		if (hflag) {
+			doit(lat1, long1, lat2, long2, height, "WWV  ");
+		} else {
+			doit(lat1, long1, lat2, long2, (double)SUMMERHEIGHT,
+			     "WWV  summer propagation, ");
+			doit(lat1, long1, lat2, long2, (double)WINTERHEIGHT,
+			     "WWV  winter propagation, ");
+		}
+
+		/*
+		 * Compute delay from WWVH
+		 */
+		lat2 = latlong(wwvhlat, 1);
+		long2 = latlong(wwvhlong, 0);
+		if (hflag) {
+			doit(lat1, long1, lat2, long2, height, "WWVH ");
+		} else {
+			doit(lat1, long1, lat2, long2, (double)SUMMERHEIGHT,
+			     "WWVH summer propagation, ");
+			doit(lat1, long1, lat2, long2, (double)WINTERHEIGHT,
+			     "WWVH winter propagation, ");
+		}
+	} else if (Cflag) {
+		lat1 = latlong(argv[ntp_optind], 1);
+		long1 = latlong(argv[ntp_optind + 1], 0);
+		lat2 = latlong(chulat, 1);
+		long2 = latlong(chulong, 0);
+		if (hflag) {
+			doit(lat1, long1, lat2, long2, height, "CHU ");
+		} else {
+			doit(lat1, long1, lat2, long2, (double)SUMMERHEIGHT,
+			     "CHU summer propagation, ");
+			doit(lat1, long1, lat2, long2, (double)WINTERHEIGHT,
+			     "CHU winter propagation, ");
+		}
+	} else if (Gflag) {
+		lat1 = latlong(goes_up_lat, 1);
+		long1 = latlong(goes_up_long, 0);
+		lat3 = latlong(argv[ntp_optind], 1);
+		long3 = latlong(argv[ntp_optind + 1], 0);
+
+		lat2 = latlong(goes_sat_lat, 1);
+
+		long2 = latlong(goes_west_long, 0);
+		satdoit(lat1, long1, lat2, long2, lat3, long3,
+			"GOES Delay via WEST");
+
+		long2 = latlong(goes_stby_long, 0);
+		satdoit(lat1, long1, lat2, long2, lat3, long3,
+			"GOES Delay via STBY");
+
+		long2 = latlong(goes_east_long, 0);
+		satdoit(lat1, long1, lat2, long2, lat3, long3,
+			"GOES Delay via EAST");
+
+	}
+	exit(0);
+}
+
+
+/*
+ * doit - compute a delay and print it
+ */
+static void
+doit(
+	double lat1,
+	double long1,
+	double lat2,
+	double long2,
+	double h,
+	char *str
+	)
+{
+	int hops;
+	double delay;
+
+	hops = finddelay(lat1, long1, lat2, long2, h, &delay);
+	printf("%sheight %g km, hops %d, delay %g seconds\n",
+	       str, h, hops, delay);
+}
+
+
+/*
+ * latlong - decode a latitude/longitude value
+ */
+static double
+latlong(
+	char *str,
+	int islat
+	)
+{
+	register char *cp;
+	register char *bp;
+	double arg;
+	double div;
+	int isneg;
+	char buf[32];
+	char *colon;
+
+	if (islat) {
+		/*
+		 * Must be north or south
+		 */
+		if (*str == 'N' || *str == 'n')
+		    isneg = 0;
+		else if (*str == 'S' || *str == 's')
+		    isneg = 1;
+		else
+		    isneg = -1;
+	} else {
+		/*
+		 * East is positive, west is negative
+		 */
+		if (*str == 'E' || *str == 'e')
+		    isneg = 0;
+		else if (*str == 'W' || *str == 'w')
+		    isneg = 1;
+		else
+		    isneg = -1;
+	}
+
+	if (isneg >= 0)
+	    str++;
+
+	colon = strchr(str, ':');
+	if (colon != NULL) {
+		/*
+		 * in hhh:mm:ss form
+		 */
+		cp = str;
+		bp = buf;
+		while (cp < colon)
+		    *bp++ = *cp++;
+		*bp = '\0';
+		cp++;
+		arg = atof(buf);
+		div = 60.0;
+		colon = strchr(cp, ':');
+		if (colon != NULL) {
+			bp = buf;
+			while (cp < colon)
+			    *bp++ = *cp++;
+			*bp = '\0';
+			cp++;
+			arg += atof(buf) / div;
+			div = 3600.0;
+		}
+		if (*cp != '\0')
+		    arg += atof(cp) / div;
+	} else {
+		arg = atof(str);
+	}
+
+	if (isneg == 1)
+	    arg = -arg;
+
+	if (debug > 2)
+	    (void) printf("latitude/longitude %s = %g\n", str, arg);
+
+	return arg;
+}
+
+
+/*
+ * greatcircle - compute the great circle distance in kilometers
+ */
+static double
+greatcircle(
+	double lat1,
+	double long1,
+	double lat2,
+	double long2
+	)
+{
+	double dg;
+	double l1r, l2r;
+
+	l1r = lat1 * RADPERDEG;
+	l2r = lat2 * RADPERDEG;
+	dg = EARTHRADIUS * acos(
+		(cos(l1r) * cos(l2r) * cos((long2-long1)*RADPERDEG))
+		+ (sin(l1r) * sin(l2r)));
+	if (debug >= 2)
+	    printf(
+		    "greatcircle lat1 %g long1 %g lat2 %g long2 %g dist %g\n",
+		    lat1, long1, lat2, long2, dg);
+	return dg;
+}
+
+
+/*
+ * waveangle - compute the wave angle for the given distance, virtual
+ *	       height and number of hops.
+ */
+static double
+waveangle(
+	double dg,
+	double h,
+	int n
+	)
+{
+	double theta;
+	double delta;
+
+	theta = dg / (EARTHRADIUS * (double)(2 * n));
+	delta = atan((h / (EARTHRADIUS * sin(theta))) + tan(theta/2)) - theta;
+	if (debug >= 2)
+	    printf("waveangle dist %g height %g hops %d angle %g\n",
+		   dg, h, n, delta / RADPERDEG);
+	return delta;
+}
+
+
+/*
+ * propdelay - compute the propagation delay
+ */
+static double
+propdelay(
+	double dg,
+	double h,
+	int n
+	)
+{
+	double phi;
+	double theta;
+	double td;
+
+	theta = dg / (EARTHRADIUS * (double)(2 * n));
+	phi = (PI/2.0) - atan((h / (EARTHRADIUS * sin(theta))) + tan(theta/2));
+	td = dg / (LIGHTSPEED * sin(phi));
+	if (debug >= 2)
+	    printf("propdelay dist %g height %g hops %d time %g\n",
+		   dg, h, n, td);
+	return td;
+}
+
+
+/*
+ * finddelay - find the propagation delay
+ */
+static int
+finddelay(
+	double lat1,
+	double long1,
+	double lat2,
+	double long2,
+	double h,
+	double *delay
+	)
+{
+	double dg;	/* great circle distance */
+	double delta;	/* wave angle */
+	int n;		/* number of hops */
+
+	dg = greatcircle(lat1, long1, lat2, long2);
+	if (debug)
+	    printf("great circle distance %g km %g miles\n", dg, dg/MILE);
+	
+	n = 1;
+	while ((delta = waveangle(dg, h, n)) < 0.0) {
+		if (debug)
+		    printf("tried %d hop%s, no good\n", n, n>1?"s":"");
+		n++;
+	}
+	if (debug)
+	    printf("%d hop%s okay, wave angle is %g\n", n, n>1?"s":"",
+		   delta / RADPERDEG);
+
+	*delay = propdelay(dg, h, n);
+	return n;
+}
+
+/*
+ * satdoit - compute a delay and print it
+ */
+static void
+satdoit(
+	double lat1,
+	double long1,
+	double lat2,
+	double long2,
+	double lat3,
+	double long3,
+	char *str
+	)
+{
+	double up_delay,down_delay;
+
+	satfinddelay(lat1, long1, lat2, long2, &up_delay);
+	satfinddelay(lat3, long3, lat2, long2, &down_delay);
+
+	printf("%s, delay %g seconds\n", str, up_delay + down_delay);
+}
+
+/*
+ * satfinddelay - calculate the one-way delay time between a ground station
+ * and a satellite
+ */
+static void
+satfinddelay(
+	double lat1,
+	double long1,
+	double lat2,
+	double long2,
+	double *delay
+	)
+{
+	double dg;	/* great circle distance */
+
+	dg = greatcircle(lat1, long1, lat2, long2);
+
+	*delay = satpropdelay(dg);
+}
+
+/*
+ * satpropdelay - calculate the one-way delay time between a ground station
+ * and a satellite
+ */
+static double
+satpropdelay(
+	double dg
+	)
+{
+	double k1, k2, dist;
+	double theta;
+	double td;
+
+	theta = dg / (EARTHRADIUS);
+	k1 = EARTHRADIUS * sin(theta);
+	k2 = SATHEIGHT - (EARTHRADIUS * cos(theta));
+	if (debug >= 2)
+	    printf("Theta %g k1 %g k2 %g\n", theta, k1, k2);
+	dist = sqrt(k1*k1 + k2*k2);
+	td = dist / LIGHTSPEED;
+	if (debug >= 2)
+	    printf("propdelay dist %g height %g time %g\n", dg, dist, td);
+	return td;
+}