-/* $NetBSD: pom.c,v 1.4 1995/03/23 08:35:36 cgd Exp $ */
+/* $NetBSD: pom.c,v 1.20 2010/12/05 04:34:22 pgoyette Exp $ */
/*
* Copyright (c) 1989, 1993
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* SUCH DAMAGE.
*/
+#include <sys/cdefs.h>
#ifndef lint
-static char copyright[] =
-"@(#) Copyright (c) 1989, 1993\n\
- The Regents of the University of California. All rights reserved.\n";
+__COPYRIGHT("@(#) Copyright (c) 1989, 1993\
+ The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)pom.c 8.1 (Berkeley) 5/31/93";
#else
-static char rcsid[] = "$NetBSD: pom.c,v 1.4 1995/03/23 08:35:36 cgd Exp $";
+__RCSID("$NetBSD: pom.c,v 1.20 2010/12/05 04:34:22 pgoyette Exp $");
#endif
#endif /* not lint */
*
* -- Keith E. Brandt VIII 1984
*
+ * Updated to the Third Edition of Duffett-Smith's book, Paul Janzen, IX 1998
+ *
*/
-#include <sys/time.h>
+#include <ctype.h>
+#include <err.h>
+#include <math.h>
#include <stdio.h>
#include <string.h>
-#include <tzfile.h>
-#include <math.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+
+#ifndef PI
+#define PI 3.14159265358979323846
+#endif
-#define PI 3.141592654
-#define EPOCH 85
-#define EPSILONg 279.611371 /* solar ecliptic long at EPOCH */
-#define RHOg 282.680403 /* solar ecliptic long of perigee at EPOCH */
-#define ECCEN 0.01671542 /* solar orbit eccentricity */
-#define lzero 18.251907 /* lunar mean long at EPOCH */
-#define Pzero 192.917585 /* lunar mean long of perigee at EPOCH */
-#define Nzero 55.204723 /* lunar mean long of node at EPOCH */
+/*
+ * The EPOCH in the third edition of the book is 1990 Jan 0.0 TDT.
+ * In this program, we do not bother to correct for the differences
+ * between UTC (as shown by the UNIX clock) and TDT. (TDT = TAI + 32.184s;
+ * TAI-UTC = 32s in Jan 1999.)
+ */
+#define EPOCH_MINUS_1970 (20 * 365 + 5 - 1) /* 20 years, 5 leaps, back 1 day to Jan 0 */
+#define EPSILONg 279.403303 /* solar ecliptic long at EPOCH */
+#define RHOg 282.768422 /* solar ecliptic long of perigee at EPOCH */
+#define ECCEN 0.016713 /* solar orbit eccentricity */
+#define lzero 318.351648 /* lunar mean long at EPOCH */
+#define Pzero 36.340410 /* lunar mean long of perigee at EPOCH */
+#define Nzero 318.510107 /* lunar mean long of node at EPOCH */
-double dtor(), potm(), adj360();
+int main(int, char *[]);
+static void adj360(double *);
+static double dtor(double);
+static double potm(double);
+static time_t parsetime(char *);
+static void badformat(void) __dead;
-main()
+int
+main(int argc, char *argv[])
{
- extern int errno;
- struct timeval tp;
- struct timezone tzp;
- struct tm *GMT, *gmtime();
+ time_t tmpt, now;
double days, today, tomorrow;
- int cnt;
+ char buf[1024];
- if (gettimeofday(&tp,&tzp)) {
- (void)fprintf(stderr, "pom: %s\n", strerror(errno));
- exit(1);
+ if (time(&now) == (time_t)-1)
+ err(1, "time");
+ if (argc > 1) {
+ tmpt = parsetime(argv[1]);
+ strftime(buf, sizeof(buf), "%a %Y %b %e %H:%M:%S (%Z)",
+ localtime(&tmpt));
+ printf("%s: ", buf);
+ } else {
+ tmpt = now;
}
- GMT = gmtime(&tp.tv_sec);
- days = (GMT->tm_yday + 1) + ((GMT->tm_hour +
- (GMT->tm_min / 60.0) + (GMT->tm_sec / 3600.0)) / 24.0);
- for (cnt = EPOCH; cnt < GMT->tm_year; ++cnt)
- days += isleap(cnt) ? 366 : 365;
+ days = (tmpt - EPOCH_MINUS_1970 * 86400) / 86400.0;
today = potm(days) + .5;
- (void)printf("The Moon is ");
+ if (tmpt < now)
+ (void)printf("The Moon was ");
+ else if (tmpt == now)
+ (void)printf("The Moon is ");
+ else
+ (void)printf("The Moon will be ");
if ((int)today == 100)
(void)printf("Full\n");
else if (!(int)today)
if ((int)today == 50)
(void)printf("%s\n", tomorrow > today ?
"at the First Quarter" : "at the Last Quarter");
+ /* today is 0.5 too big, but it doesn't matter here
+ * since the phase is changing fast enough
+ */
else {
+ today -= 0.5; /* Now it might matter */
(void)printf("%s ", tomorrow > today ?
"Waxing" : "Waning");
if (today > 50)
today);
}
}
- exit(0);
+
+ return EXIT_SUCCESS;
}
/*
* potm --
* return phase of the moon
*/
-double
-potm(days)
- double days;
+static double
+potm(double days)
{
double N, Msol, Ec, LambdaSol, l, Mm, Ev, Ac, A3, Mmprime;
double A4, lprime, V, ldprime, D, Nm;
- N = 360 * days / 365.2422; /* sec 42 #3 */
+ N = 360 * days / 365.242191; /* sec 46 #3 */
adj360(&N);
- Msol = N + EPSILONg - RHOg; /* sec 42 #4 */
+ Msol = N + EPSILONg - RHOg; /* sec 46 #4 */
adj360(&Msol);
- Ec = 360 / PI * ECCEN * sin(dtor(Msol)); /* sec 42 #5 */
- LambdaSol = N + Ec + EPSILONg; /* sec 42 #6 */
+ Ec = 360 / PI * ECCEN * sin(dtor(Msol)); /* sec 46 #5 */
+ LambdaSol = N + Ec + EPSILONg; /* sec 46 #6 */
adj360(&LambdaSol);
- l = 13.1763966 * days + lzero; /* sec 61 #4 */
+ l = 13.1763966 * days + lzero; /* sec 65 #4 */
adj360(&l);
- Mm = l - (0.1114041 * days) - Pzero; /* sec 61 #5 */
+ Mm = l - (0.1114041 * days) - Pzero; /* sec 65 #5 */
adj360(&Mm);
- Nm = Nzero - (0.0529539 * days); /* sec 61 #6 */
+ Nm = Nzero - (0.0529539 * days); /* sec 65 #6 */
adj360(&Nm);
- Ev = 1.2739 * sin(dtor(2*(l - LambdaSol) - Mm)); /* sec 61 #7 */
- Ac = 0.1858 * sin(dtor(Msol)); /* sec 61 #8 */
+ Ev = 1.2739 * sin(dtor(2*(l - LambdaSol) - Mm)); /* sec 65 #7 */
+ Ac = 0.1858 * sin(dtor(Msol)); /* sec 65 #8 */
A3 = 0.37 * sin(dtor(Msol));
- Mmprime = Mm + Ev - Ac - A3; /* sec 61 #9 */
- Ec = 6.2886 * sin(dtor(Mmprime)); /* sec 61 #10 */
- A4 = 0.214 * sin(dtor(2 * Mmprime)); /* sec 61 #11 */
- lprime = l + Ev + Ec - Ac + A4; /* sec 61 #12 */
- V = 0.6583 * sin(dtor(2 * (lprime - LambdaSol))); /* sec 61 #13 */
- ldprime = lprime + V; /* sec 61 #14 */
- D = ldprime - LambdaSol; /* sec 63 #2 */
- return(50 * (1 - cos(dtor(D)))); /* sec 63 #3 */
+ Mmprime = Mm + Ev - Ac - A3; /* sec 65 #9 */
+ Ec = 6.2886 * sin(dtor(Mmprime)); /* sec 65 #10 */
+ A4 = 0.214 * sin(dtor(2 * Mmprime)); /* sec 65 #11 */
+ lprime = l + Ev + Ec - Ac + A4; /* sec 65 #12 */
+ V = 0.6583 * sin(dtor(2 * (lprime - LambdaSol))); /* sec 65 #13 */
+ ldprime = lprime + V; /* sec 65 #14 */
+ D = ldprime - LambdaSol; /* sec 67 #2 */
+ return(50.0 * (1 - cos(dtor(D)))); /* sec 67 #3 */
}
/*
* dtor --
* convert degrees to radians
*/
-double
-dtor(deg)
- double deg;
+static double
+dtor(double deg)
{
return(deg * PI / 180);
}
* adj360 --
* adjust value so 0 <= deg <= 360
*/
-double
-adj360(deg)
- double *deg;
+static void
+adj360(double *deg)
{
for (;;)
if (*deg < 0)
else
break;
}
+
+#define ATOI2(ar) ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
+static time_t
+parsetime(char *p)
+{
+ struct tm *lt;
+ int bigyear;
+ int yearset = 0;
+ time_t tval;
+ char *t;
+
+ for (t = p; *t; ++t) {
+ if (isdigit((unsigned char) *t))
+ continue;
+ badformat();
+ }
+
+ tval = time(NULL);
+ lt = localtime(&tval);
+ lt->tm_sec = 0;
+ lt->tm_min = 0;
+
+ switch (strlen(p)) {
+ case 10: /* yyyy */
+ bigyear = ATOI2(p);
+ lt->tm_year = bigyear * 100 - 1900;
+ yearset = 1;
+ /* FALLTHROUGH */
+ case 8: /* yy */
+ if (yearset) {
+ lt->tm_year += ATOI2(p);
+ } else {
+ lt->tm_year = ATOI2(p);
+ if (lt->tm_year < 69) /* hack for 2000 */
+ lt->tm_year += 100;
+ }
+ /* FALLTHROUGH */
+ case 6: /* mm */
+ lt->tm_mon = ATOI2(p);
+ if ((lt->tm_mon > 12) || !lt->tm_mon)
+ badformat();
+ --lt->tm_mon; /* time struct is 0 - 11 */
+ /* FALLTHROUGH */
+ case 4: /* dd */
+ lt->tm_mday = ATOI2(p);
+ if ((lt->tm_mday > 31) || !lt->tm_mday)
+ badformat();
+ /* FALLTHROUGH */
+ case 2: /* HH */
+ lt->tm_hour = ATOI2(p);
+ if (lt->tm_hour > 23)
+ badformat();
+ break;
+ default:
+ badformat();
+ }
+ /* The calling code needs a valid tm_ydays and this is the easiest
+ * way to get one */
+ if ((tval = mktime(lt)) == -1)
+ errx(1, "specified date is outside allowed range");
+ return (tval);
+}
+
+static void
+badformat(void)
+{
+ warnx("illegal time format");
+ (void)fprintf(stderr, "usage: %s [[[[[cc]yy]mm]dd]HH]\n",
+ getprogname());
+ exit(EXIT_FAILURE);
+}