--- /dev/null
+
+/*
+ * dtime.c -- time/date routines
+ *
+ * $Id$
+ */
+
+#include <h/mh.h> /* for snprintf() */
+#include <h/nmh.h>
+#include <h/tws.h>
+
+#if !defined(HAVE_TM_GMTOFF) && !defined(HAVE_TZSET)
+# include <sys/timeb.h>
+#endif
+
+#ifdef TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+# else
+# include <time.h>
+# endif
+#endif
+
+#if !defined(HAVE_TM_GMTOFF) && defined(HAVE_TZSET)
+extern int daylight;
+extern long timezone;
+extern char *tzname[];
+#endif
+
+#ifndef abs
+# define abs(a) (a >= 0 ? a : -a)
+#endif
+
+/*
+ * The number of days in the year, accounting for leap years
+ */
+#define dysize(y) \
+ (((y) % 4) ? 365 : (((y) % 100) ? 366 : (((y) % 400) ? 365 : 366)))
+
+char *tw_moty[] = {
+ "Jan", "Feb", "Mar", "Apr",
+ "May", "Jun", "Jul", "Aug",
+ "Sep", "Oct", "Nov", "Dec",
+ NULL
+};
+
+char *tw_dotw[] = {
+ "Sun", "Mon", "Tue",
+ "Wed", "Thu", "Fri",
+ "Sat", NULL
+};
+
+char *tw_ldotw[] = {
+ "Sunday", "Monday", "Tuesday",
+ "Wednesday", "Thursday", "Friday",
+ "Saturday", NULL
+};
+
+struct zone {
+ char *std;
+ char *dst;
+ int shift;
+};
+
+static struct zone zones[] = {
+ { "GMT", "BST", 0 },
+ { "EST", "EDT", -5 },
+ { "CST", "CDT", -6 },
+ { "MST", "MDT", -7 },
+ { "PST", "PDT", -8 },
+#if 0
+/* RFC1123 specifies do not use military TZs */
+ { "A", NULL, -1 },
+ { "B", NULL, -2 },
+ { "C", NULL, -3 },
+ { "D", NULL, -4 },
+ { "E", NULL, -5 },
+ { "F", NULL, -6 },
+ { "G", NULL, -7 },
+ { "H", NULL, -8 },
+ { "I", NULL, -9 },
+ { "K", NULL, -10 },
+ { "L", NULL, -11 },
+ { "M", NULL, -12 },
+ { "N", NULL, 1 },
+#ifndef HUJI
+ { "O", NULL, 2 },
+#else
+ { "JST", "JDT", 2 },
+#endif
+ { "P", NULL, 3 },
+ { "Q", NULL, 4 },
+ { "R", NULL, 5 },
+ { "S", NULL, 6 },
+ { "T", NULL, 7 },
+ { "U", NULL, 8 },
+ { "V", NULL, 9 },
+ { "W", NULL, 10 },
+ { "X", NULL, 11 },
+ { "Y", NULL, 12 },
+#endif
+ { NULL, NULL, 0 }
+};
+
+static int dmsize[] = {
+ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
+};
+
+
+/*
+ * Get current time (adjusted for local time
+ * zone and daylight savings time) expressed
+ * as nmh "broken-down" time structure.
+ */
+
+struct tws *
+dlocaltimenow (void)
+{
+ time_t clock;
+
+ time (&clock);
+ return dlocaltime (&clock);
+}
+
+
+/*
+ * Take clock value and return pointer to nmh time structure
+ * containing "broken-down" time. The time is adjusted for
+ * local time zone and daylight savings time.
+ */
+
+struct tws *
+dlocaltime (time_t *clock)
+{
+ static struct tws tw;
+ struct tm *tm;
+
+#if !defined(HAVE_TM_GMTOFF) && !defined(HAVE_TZSET)
+ struct timeb tb;
+#endif
+
+ if (!clock)
+ return NULL;
+
+ tm = localtime (clock);
+
+ tw.tw_sec = tm->tm_sec;
+ tw.tw_min = tm->tm_min;
+ tw.tw_hour = tm->tm_hour;
+ tw.tw_mday = tm->tm_mday;
+ tw.tw_mon = tm->tm_mon;
+
+ /*
+ * tm_year is always "year - 1900".
+ * So we correct for this.
+ */
+ tw.tw_year = tm->tm_year + 1900;
+ tw.tw_wday = tm->tm_wday;
+ tw.tw_yday = tm->tm_yday;
+
+ tw.tw_flags = TW_NULL;
+ if (tm->tm_isdst)
+ tw.tw_flags |= TW_DST;
+
+#ifdef HAVE_TM_GMTOFF
+ tw.tw_zone = tm->tm_gmtoff / 60;
+ if (tm->tm_isdst) /* if DST is in effect */
+ tw.tw_zone -= 60; /* reset to normal offset */
+#else
+# ifdef HAVE_TZSET
+ tzset();
+ tw.tw_zone = -(timezone / 60);
+# else
+ ftime (&tb);
+ tw.tw_zone = -tb.timezone;
+# endif
+#endif
+
+ tw.tw_flags &= ~TW_SDAY;
+ tw.tw_flags |= TW_SEXP;
+ tw.tw_flags &= ~TW_SZONE;
+ tw.tw_flags |= TW_SZEXP;
+
+ tw.tw_clock = *clock;
+
+ return (&tw);
+}
+
+
+/*
+ * Take clock value and return pointer to nmh time
+ * structure containing "broken-down" time. Time is
+ * expressed in UTC (Coordinated Universal Time).
+ */
+
+struct tws *
+dgmtime (time_t *clock)
+{
+ static struct tws tw;
+ struct tm *tm;
+
+ if (!clock)
+ return NULL;
+
+ tm = gmtime (clock);
+
+ tw.tw_sec = tm->tm_sec;
+ tw.tw_min = tm->tm_min;
+ tw.tw_hour = tm->tm_hour;
+ tw.tw_mday = tm->tm_mday;
+ tw.tw_mon = tm->tm_mon;
+
+ /*
+ * tm_year is always "year - 1900"
+ * So we correct for this.
+ */
+ tw.tw_year = tm->tm_year + 1900;
+ tw.tw_wday = tm->tm_wday;
+ tw.tw_yday = tm->tm_yday;
+
+ tw.tw_flags = TW_NULL;
+ if (tm->tm_isdst)
+ tw.tw_flags |= TW_DST;
+
+ tw.tw_zone = 0;
+
+ tw.tw_flags &= ~TW_SDAY;
+ tw.tw_flags |= TW_SEXP;
+ tw.tw_flags &= ~TW_SZONE;
+ tw.tw_flags |= TW_SZEXP;
+
+ tw.tw_clock = *clock;
+
+ return (&tw);
+}
+
+
+/*
+ * Using a nmh "broken-down" time structure,
+ * produce a 26-byte date/time string, such as
+ *
+ * Tue Jan 14 17:49:03 1992\n\0
+ */
+
+char *
+dctime (struct tws *tw)
+{
+ static char buffer[26];
+
+ if (!tw)
+ return NULL;
+
+ snprintf (buffer, sizeof(buffer), "%.3s %.3s %02d %02d:%02d:%02d %.4d\n",
+ tw_dotw[tw->tw_wday], tw_moty[tw->tw_mon], tw->tw_mday,
+ tw->tw_hour, tw->tw_min, tw->tw_sec,
+ tw->tw_year < 100 ? tw->tw_year + 1900 : tw->tw_year);
+
+ return buffer;
+}
+
+
+/*
+ * Produce a date/time string of the form
+ *
+ * Mon, 16 Jun 1992 15:30:48 -700 (or)
+ * Mon, 16 Jun 1992 15:30:48 EDT
+ *
+ * for the current time, as specified by rfc822.
+ * The first form is required by rfc1123.
+ */
+
+char *
+dtimenow (int alpha_timezone)
+{
+ time_t clock;
+
+ time (&clock);
+ return dtime (&clock, alpha_timezone);
+}
+
+
+/*
+ * Using a local calendar time value, produce
+ * a date/time string of the form
+ *
+ * Mon, 16 Jun 1992 15:30:48 -700 (or)
+ * Mon, 16 Jun 1992 15:30:48 EDT
+ *
+ * as specified by rfc822. The first form is required
+ * by rfc1123 for outgoing messages.
+ */
+
+char *
+dtime (time_t *clock, int alpha_timezone)
+{
+ if (alpha_timezone)
+ /* use alpha-numeric timezones */
+ return dasctime (dlocaltime (clock), TW_NULL);
+ else
+ /* use numeric timezones */
+ return dasctime (dlocaltime (clock), TW_ZONE);
+}
+
+
+/*
+ * Using a nmh "broken-down" time structure, produce
+ * a date/time string of the form
+ *
+ * Mon, 16 Jun 1992 15:30:48 -0700
+ *
+ * as specified by rfc822 and rfc1123.
+ */
+
+char *
+dasctime (struct tws *tw, int flags)
+{
+ char buffer[80];
+ static char result[80];
+
+ if (!tw)
+ return NULL;
+
+ /* Display timezone if known */
+ if ((tw->tw_flags & TW_SZONE) == TW_SZNIL)
+ result[0] = '\0';
+ else
+ snprintf(result, sizeof(result), " %s", dtimezone(tw->tw_zone, tw->tw_flags | flags));
+
+ snprintf(buffer, sizeof(buffer), "%02d %s %0*d %02d:%02d:%02d%s",
+ tw->tw_mday, tw_moty[tw->tw_mon],
+ tw->tw_year < 100 ? 2 : 4, tw->tw_year,
+ tw->tw_hour, tw->tw_min, tw->tw_sec, result);
+
+ if ((tw->tw_flags & TW_SDAY) == TW_SEXP)
+ snprintf (result, sizeof(result), "%s, %s", tw_dotw[tw->tw_wday], buffer);
+ else
+ if ((tw->tw_flags & TW_SDAY) == TW_SNIL)
+ strncpy (result, buffer, sizeof(result));
+ else
+ snprintf (result, sizeof(result), "%s (%s)", buffer, tw_dotw[tw->tw_wday]);
+
+ return result;
+}
+
+
+/*
+ * Get the timezone for given offset
+ */
+
+char *
+dtimezone (int offset, int flags)
+{
+ int hours, mins;
+ struct zone *z;
+ static char buffer[10];
+
+ if (offset < 0) {
+ mins = -((-offset) % 60);
+ hours = -((-offset) / 60);
+ } else {
+ mins = offset % 60;
+ hours = offset / 60;
+ }
+
+ if (!(flags & TW_ZONE) && mins == 0) {
+#if defined(HAVE_TZSET) && defined(HAVE_TZNAME)
+ tzset();
+ return ((flags & TW_DST) ? tzname[1] : tzname[0]);
+#else
+ for (z = zones; z->std; z++)
+ if (z->shift == hours)
+ return (z->dst && (flags & TW_DST) ? z->dst : z->std);
+#endif
+ }
+
+#if defined(DSTXXX)
+ if (flags & TW_DST)
+ hours += 1;
+#endif /* defined(DSTXXX) */
+ snprintf (buffer, sizeof(buffer), "%s%02d%02d",
+ offset < 0 ? "-" : "+", abs (hours), abs (mins));
+ return buffer;
+}
+
+
+/*
+ * Convert nmh time structure for local "broken-down"
+ * time to calendar time (clock value). This routine
+ * is based on the gtime() routine written by Steven Shafer
+ * at CMU. It was forwarded to MTR by Jay Lepreau at Utah-CS.
+ */
+
+time_t
+dmktime (struct tws *tw)
+{
+ int i, sec, min, hour, mday, mon, year;
+ time_t result;
+
+ if (tw->tw_clock != 0)
+ return tw->tw_clock;
+
+ if ((sec = tw->tw_sec) < 0 || sec > 61
+ || (min = tw->tw_min) < 0 || min > 59
+ || (hour = tw->tw_hour) < 0 || hour > 23
+ || (mday = tw->tw_mday) < 1 || mday > 31
+ || (mon = tw->tw_mon + 1) < 1 || mon > 12)
+ return (tw->tw_clock = (time_t) -1);
+
+ year = tw->tw_year;
+
+ result = 0;
+ if (year < 100)
+ year += 1900;
+
+ for (i = 1970; i < year; i++)
+ result += dysize (i);
+ if (dysize (year) == 366 && mon >= 3)
+ result++;
+ while (--mon)
+ result += dmsize[mon - 1];
+ result += mday - 1;
+ result = 24 * result + hour;
+ result = 60 * result + min;
+ result = 60 * result + sec;
+ result -= 60 * tw->tw_zone;
+ if (tw->tw_flags & TW_DST)
+ result -= 60 * 60;
+
+ return (tw->tw_clock = result);
+}
+
+
+/*
+ * Simple calculation of day of the week. Algorithm
+ * used is Zeller's congruence. We assume that
+ * if tw->tw_year < 100, then the century = 19.
+ */
+
+void
+set_dotw (struct tws *tw)
+{
+ int month, day, year, century;
+
+ month = tw->tw_mon - 1;
+ day = tw->tw_mday;
+ year = tw->tw_year % 100;
+ century = tw->tw_year < 100 ? 19 : tw->tw_year / 100;
+
+ if (month <= 0) {
+ month += 12;
+ if (--year < 0) {
+ year += 100;
+ century--;
+ }
+ }
+
+ tw->tw_wday =
+ ((26 * month - 2) / 10 + day + year + year / 4
+ - 3 * century / 4 + 1) % 7;
+ if (tw->tw_wday < 0)
+ tw->tw_wday += 7;
+
+ tw->tw_flags &= ~TW_SDAY, tw->tw_flags |= TW_SIMP;
+}
+
+
+/*
+ * Copy nmh time structure
+ */
+
+void
+twscopy (struct tws *tb, struct tws *tw)
+{
+ *tb = *tw; /* struct copy */
+
+#if 0
+ tb->tw_sec = tw->tw_sec;
+ tb->tw_min = tw->tw_min;
+ tb->tw_hour = tw->tw_hour;
+ tb->tw_mday = tw->tw_mday;
+ tb->tw_mon = tw->tw_mon;
+ tb->tw_year = tw->tw_year;
+ tb->tw_wday = tw->tw_wday;
+ tb->tw_yday = tw->tw_yday;
+ tb->tw_zone = tw->tw_zone;
+ tb->tw_clock = tw->tw_clock;
+ tb->tw_flags = tw->tw_flags;
+#endif
+}
+
+
+/*
+ * Compare two nmh time structures
+ */
+
+int
+twsort (struct tws *tw1, struct tws *tw2)
+{
+ time_t c1, c2;
+
+ if (tw1->tw_clock == 0)
+ dmktime (tw1);
+ if (tw2->tw_clock == 0)
+ dmktime (tw2);
+
+ return ((c1 = tw1->tw_clock) > (c2 = tw2->tw_clock) ? 1
+ : c1 == c2 ? 0 : -1);
+}
projects / mmh / blobdiff