Initial revision

scaldate.h

@@ -0,0 +1,83 @@
+/* +++Date last modified: 05-Jul-1997 */
+
+/*
+** scalar date routines    --    public domain by Ray Gardner
+** Numerically, these will work over the range 1/01/01 thru 14699/12/31.
+** Practically, these only work from the beginning of the Gregorian
+** calendar thru 14699/12/31.  The Gregorian calendar took effect in
+** much of Europe in about 1582, some parts of Germany in about 1700, in
+** England and the colonies in about 1752ff, and in Russia in 1918.
+*/
+
+#ifndef SCALDATE__H
+#define SCALDATE__H
+
+/* #include "sniptype.h" */
+
+/*
+**  Define ISO_CAL to be 1 for ISO (Mon-Sun) calendars
+**
+**  ISO defines the first week with 4 or more days in it to be week #1.
+*/
+
+#ifndef ISO_CAL
+ #define ISO_CAL 0
+#endif
+
+#if (ISO_CAL != 0 && ISO_CAL != 1)
+ #error ISO_CAL must be set to either 0 or 1
+#endif
+
+#if ISO_CAL
+ enum DOW_T {DOW_IGNORE = -1,
+       MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY};
+#else
+ enum DOW_T {DOW_IGNORE = -1,
+       SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY};
+#endif
+
+/*
+**  Daylight savings time rules.
+**
+**  Rules include a month, date, and day. If the day is DOW_IGNORE, DST will
+**  start on the month and date specified. If a day is specified (the
+**  interpretation of the day parameter is subject to the value of ISO_CAL),
+**  DST will start on the first such day following (or equal to) the specified
+**  date, or stop on the first such day preceding (or equal to) the specified
+**  date.
+**
+**  The defaults defined for the U.S. mean that DST will begin on the first
+**  Sunday after (or on) April 1 and end on the last Sunday preceding (or on)
+**  October 31.
+*/
+
+extern unsigned   DST_start_mo;
+extern unsigned   DST_start_dt;
+extern enum DOW_T DST_start_dy;
+
+extern unsigned   DST_stop_mo;
+extern unsigned   DST_stop_dt;
+extern enum DOW_T DST_stop_dy;
+
+int  isleap (unsigned yr);
+long ymd_to_scalar (unsigned yr, unsigned mo, unsigned day);
+void scalar_to_ymd (long scalar, unsigned *yr, unsigned *mo, unsigned *day);
+int  daynum(int year, int month, int day);
+int  weeknum(int year, int month, int day);
+
+int valiDate(unsigned yr, unsigned mo, unsigned day);
+
+unsigned dow(unsigned yr, unsigned mo, unsigned day);
+unsigned DOW(unsigned y, unsigned m, unsigned d);
+
+long today(void);
+
+extern char *MoonPhaseText[8];
+
+unsigned moonphase(unsigned yr, unsigned mo, unsigned dy);
+
+int getfdate (int handle, long *date);
+int getdatef (char *fname, long *date);
+
+
+#endif /* SCALDATE__H */