===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/calendar/day.c,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -r1.6 -r1.7
--- src/usr.bin/calendar/day.c	1998/11/08 04:31:13	1.6
+++ src/usr.bin/calendar/day.c	1998/12/13 07:31:07	1.7
@@ -1,4 +1,4 @@
-/*	$OpenBSD: day.c,v 1.6 1998/11/08 04:31:13 pjanzen Exp $	*/
+/*	$OpenBSD: day.c,v 1.7 1998/12/13 07:31:07 pjanzen Exp $	*/
 
 /*
  * Copyright (c) 1989, 1993, 1994
@@ -43,7 +43,7 @@
 #if 0
 static const char sccsid[] = "@(#)calendar.c  8.3 (Berkeley) 3/25/94";
 #else
-static char rcsid[] = "$OpenBSD: day.c,v 1.6 1998/11/08 04:31:13 pjanzen Exp $";
+static char rcsid[] = "$OpenBSD: day.c,v 1.7 1998/12/13 07:31:07 pjanzen Exp $";
 #endif
 #endif /* not lint */
 
@@ -62,8 +62,12 @@
 #include "pathnames.h"
 #include "calendar.h"
 
+#define WEEKLY 1
+#define MONTHLY 2
+#define YEARLY 3
+
 struct tm *tp;
-int *cumdays, offset, yrdays;
+int *cumdays, offset;
 char dayname[10];
 
 
@@ -140,22 +144,39 @@
 			errx(1, "cannot allocate memory");
 		fnmonths[i].len = strlen(buf);
 	}
+	/* Hardwired special events */
+	spev[0].name = strdup(EASTER);
+	spev[0].nlen = EASTERNAMELEN;
+	spev[0].getev = easter;
+	spev[1].name = strdup(PASKHA);
+	spev[1].nlen = PASKHALEN;
+	spev[1].getev = paskha;
+	for (i = 0; i < NUMEV; i++) {
+		if (spev[i].name == NULL)
+			errx(1, "cannot allocate memory");
+		spev[i].uname = NULL;
+	}
 }
 
 void
 settime(now)
-    	time_t now;
+	time_t *now;
 {
-	tp = localtime(&now);
-	if (isleap(tp->tm_year + TM_YEAR_BASE)) {
-		yrdays = DAYSPERLYEAR;
+	tp = localtime(now);
+	tp->tm_sec = 0;
+	tp->tm_min = 0;
+	/* Avoid getting caught by a timezone shift; set time to noon */
+	tp->tm_isdst = 0;
+	tp->tm_hour = 12;
+	*now = mktime(tp);
+	if (isleap(tp->tm_year + TM_YEAR_BASE))
 		cumdays = daytab[1];
-	} else {
-		yrdays = DAYSPERNYEAR;
+	else
 		cumdays = daytab[0];
-	}
 	/* Friday displays Monday's events */
 	offset = tp->tm_wday == 5 ? 3 : 1;
+	if (f_dayAfter)
+		offset = 0;	/* Except not when range is set explicitly */
 	header[5].iov_base = dayname;
 
 	(void) setlocale(LC_TIME, "C");
@@ -202,8 +223,8 @@
 
     /* Year */
     if (len >= 6) {
-	*(date + len - 4) = '\0';
-	tm.tm_year = atoi(date);
+		*(date + len - 4) = '\0';
+		tm.tm_year = atoi(date);
 
 	/* tm_year up TM_YEAR_BASE ... */
 	if (tm.tm_year < 69)		/* Y2K */
@@ -235,9 +256,13 @@
 isnow(endp)
 	char	*endp;
 {
-	int day, flags = 0, month = 0, v1, v2;
-	int monthp, dayp, varp;
-	struct match *matches;
+	int day = 0, flags = 0, month = 0, v1, v2, i;
+	int monthp, dayp, varp = 0;
+	struct match *matches = NULL, *tmp, *tmp2;
+	int interval = YEARLY;	/* how frequently the event repeats. */
+	int vwd = 0;	/* Variable weekday */
+	time_t tdiff, ttmp;
+	struct tm tmtmp;
 
 	/*
 	 * CONVENTION
@@ -255,8 +280,8 @@
 		return (NULL);
 
 	/* Easter or Easter depending days */
-	if (flags & F_EASTER)
-	    day = v1 - 1; /* days since January 1 [0-365] */
+	if (flags & F_SPECIAL)
+		vwd = v1;
 
 	 /*
 	  * 1. {Weekday,Day} XYZ ...
@@ -265,24 +290,47 @@
 	  */
 	else if (flags & F_ISDAY || v1 > 12) {
 
-		/* found a day; day: 1-31 or weekday: 1-7 */
+		/* found a day; day: 13-31 or weekday: 1-7 */
 		day = v1;
 
 		/* {Day,Weekday} {Month,Monthname} ... */
-		/* if no recognizable month, assume just a day alone
-		 * in other words, find month or use current month */
-		if (!(month = getfield(endp, &endp, &flags)))
+		/* if no recognizable month, assume just a day alone -- this is
+		 * very unlikely and can only happen after the first 12 days.
+		 * --find month or use current month */
+		if (!(month = getfield(endp, &endp, &flags))) {
 			month = tp->tm_mon + 1;
+			/* F_ISDAY is set only if a weekday was spelled out */
+			/* F_ISDAY must be set if 0 < day < 8 */
+			if ((day <= 7) && (day >= 1))
+				interval = WEEKLY;
+			else
+				interval = MONTHLY;
+		} else if ((day <= 7) && (day >= 1))
+			day += 10;
+			/* it's a weekday; make it the first one of the month */
+		if (month == -1) {
+			month = tp->tm_mon + 1;
+			interval = MONTHLY;
+		}
+		if ((month > 12) || (month < 1))
+			return (NULL);
 	}
 
 	/* 2. {Monthname} XYZ ... */
 	else if (flags & F_ISMONTH) {
 		month = v1;
-
+		if (month == -1) {
+			month = tp->tm_mon + 1;
+			interval = MONTHLY;
+		}
 		/* Monthname {day,weekday} */
 		/* if no recognizable day, assume the first day in month */
 		if (!(day = getfield(endp, &endp, &flags)))
 			day = 1;
+		/* If a weekday was spelled out without an ordering,
+		 * assume the first of that day in the month */
+		if ((flags & F_ISDAY) && (day >= 1) && (day <=7))
+			day += 10;
 	}
 
 	/* Hm ... */
@@ -296,7 +344,10 @@
 		if (flags & F_ISMONTH) {
 			day = v1;
 			month = v2;
-			varp = 0;
+			if (month == -1) {
+				month = tp->tm_mon + 1;
+				interval = MONTHLY;
+			}
 		}
 
 		/* {Month} {Weekday,Day} ...  */
@@ -305,7 +356,8 @@
 			month = v1;
 			/* if no recognizable day, assume the first */
 			day = v2 ? v2 : 1;
-			varp = 0;
+			if ((flags & F_ISDAY) && (day >= 1) && (day <= 7))
+				day += 10;
 		}
 	}
 
@@ -315,85 +367,167 @@
 	 */
 	if (flags & F_ISDAY) {
 #if DEBUG
-	    fprintf(stderr, "\nday: %d %s month %d\n", day, endp, month);
+		fprintf(stderr, "\nday: %d %s month %d\n", day, endp, month);
 #endif
 
-	    varp = 1;
-	    /* variable weekday, SundayLast, MondayFirst ... */
-	    if (day < 0 || day >= 10) {
-
-		/* negative offset; last, -4 .. -1 */
-		if (day < 0) {
-		    v1 = day/10 - 1;          /* offset -4 ... -1 */
-		    day = 10 + (day % 10);    /* day 1 ... 7 */
-
-		    /* which weekday the end of the month is (1-7) */
-		    v2 = (cumdays[month + 1] - tp->tm_yday +
-		        tp->tm_wday + 371) % 7 + 1;
-
-		    /* and subtract enough days */
-		    day = cumdays[month + 1] - cumdays[month] +
-		        (v1 + 1) * 7 - (v2 - day + 7) % 7;
-#if DEBUG
-		    fprintf(stderr, "\nMonth %d ends on weekday %d\n", month, v2);
-#endif
+		varp = 1;
+		/* variable weekday, SundayLast, MondayFirst ... */
+		if (day < 0 || day >= 10)
+			vwd = day;
+		else {
+			day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
+			interval = WEEKLY;
 		}
+	} else
+	/* Check for silliness.  Note we still catch Feb 29 */
+		if (!(flags & F_SPECIAL) &&
+		    (day > (cumdays[month + 1] - cumdays[month]) || day < 1)) {
+			if (!((month == 2 && day == 29) ||
+			    (interval == MONTHLY && day <= 31)))
+				return (NULL);
+		}
 
-		/* first, second ... +1 ... +5 */
-		else {
-		    v1 = day/10;        /* offset */
-		    day = day % 10;
-
-		    /* which weekday the first of the month is */
-		    v2 = (cumdays[month] - tp->tm_yday +
-		        tp->tm_wday + 372) % 7 + 1;
-		    
-		    /* and add enough days */
-		    day = 1 + (v1 - 1) * 7 + (day - v2 + 7) % 7;
+	if (!(flags & F_SPECIAL)) {
+		monthp = month;
+		dayp = day;
+		day = cumdays[month] + day;
 #if DEBUG
-		    fprintf(stderr, "\nMonth %d starts on weekday %d\n", month, v2);
+		fprintf(stderr, "day2: day %d(%d) yday %d\n", dayp, day, tp->tm_yday);
 #endif
-	    }
-	    }
-	    else
-		    day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
+	/* Speed up processing for the most common situation:  yearly events
+	 * when the interval being checked is less than a month or so (this
+	 * could be less than a year, but then we have to start worrying about
+	 * leap years).  Only one event can match, and it's easy to find.
+	 * Note we can't check special events, because they can wander widely.
+	 */
+		if (((v1 = offset + f_dayAfter) < 50) && (interval == YEARLY)) {
+			memcpy(&tmtmp, tp, sizeof(struct tm));
+			tmtmp.tm_mday = dayp;
+			tmtmp.tm_mon = monthp - 1;
+			v2 = day - tp->tm_yday;
+			if ((v2 > v1) || (v2 < 0)) {
+				if ((v2 += isleap(tp->tm_year + TM_YEAR_BASE) ? 366 : 365)
+				    <= v1)
+					tmtmp.tm_year++;
+				else
+					return(NULL);
+			}
+			if ((tmp = malloc(sizeof(struct match))) == NULL)
+				errx(1, "cannot allocate memory");
+			tmp->when = f_time + v2 * SECSPERDAY;
+			(void)mktime(&tmtmp);
+			if (strftime(tmp->print_date,
+			    sizeof(tmp->print_date),
+			/*    "%a %b %d", &tm);  Skip weekdays */
+			    "%b %d", &tmtmp) == 0)
+				tmp->print_date[sizeof(tmp->print_date) - 1] = '\0';
+			tmp->var   = varp;
+			tmp->next  = NULL;
+			return(tmp);
+		}
 	}
-
-	if (!(flags & F_EASTER)) {
-	    monthp = month;
-	    dayp = day;
-	    day = cumdays[month] + day;
-	}
 	else {
-	    for (v1 = 0; day > cumdays[v1]; v1++)
-		;
-	    monthp = v1 - 1;
-	    dayp = day - cumdays[v1 - 1];
-	    varp = 1;
+		varp = 1;
+		/* Set up v1 to the event number and ... */
+		v1 = vwd % (NUMEV + 1) - 1;
+		vwd /= (NUMEV + 1);
+		if (v1 < 0) {
+			v1 += NUMEV + 1;
+			vwd--;
+		}
+		dayp = monthp = 1;	/* Why not */
 	}
 
-#if DEBUG
-	fprintf(stderr, "day2: day %d(%d) yday %d\n", dayp, day, tp->tm_yday);
-#endif
-	/* if today or today + offset days */
-	if ((day >= tp->tm_yday - f_dayBefore &&
-	    day <= tp->tm_yday + offset + f_dayAfter) ||
-
-	/* if number of days left in this year + days to event in next year */
-	   (yrdays - tp->tm_yday + day <= offset + f_dayAfter ||
-	    /* a year backward, eg. 6 Jan and 10 days before -> 27. Dec */
-	    tp->tm_yday + day - f_dayBefore < 0
-	    )) {
-		if ((matches = malloc(sizeof(struct match))) == NULL)
-			errx(1,"cannot allocate memory");
-		matches->month = monthp;
-		matches->day   = dayp;
-		matches->var   = varp;
-		matches->year  = tp->tm_year;	/* XXX */
-		matches->next  = NULL;
-		return (matches);
+	/* Compare to past and coming instances of the event.  The i == 0 part
+	 * of the loop corresponds to this specific instance.  Note that we
+	 * can leave things sort of higgledy-piggledy since a mktime() happens
+	 * on this before anything gets printed.  Also note that even though
+	 * we've effectively gotten rid of f_dayBefore, we still have to check
+	 * the one prior event for situations like "the 31st of every month"
+	 * and "yearly" events which could happen twice in one year but not in
+	 * the next */
+	tmp2 = matches;
+	for (i = -1; i < 2; i++) {
+		memcpy(&tmtmp, tp, sizeof(struct tm));
+		tmtmp.tm_mday = dayp;
+		tmtmp.tm_mon = month = monthp - 1;
+		do {
+			v2 = 0;
+			switch (interval) {
+			case WEEKLY:
+				tmtmp.tm_mday += 7 * i;
+				break;
+			case MONTHLY:
+				month += i;
+				tmtmp.tm_mon = month;
+				switch(tmtmp.tm_mon) {
+				case -1:
+					tmtmp.tm_mon = month = 11;
+					tmtmp.tm_year--;
+					break;
+				case 12:
+					tmtmp.tm_mon = month = 0;
+					tmtmp.tm_year++;
+					break;
+				}
+				if (vwd) {
+					v1 = vwd;
+					variable_weekday(&v1, tmtmp.tm_mon + 1,
+					    tmtmp.tm_year + TM_YEAR_BASE);
+					tmtmp.tm_mday = v1;
+				} else
+					tmtmp.tm_mday = dayp;
+				break;
+			case YEARLY:
+			default:
+				tmtmp.tm_year += i;
+				if (flags & F_SPECIAL) {
+					tmtmp.tm_mon = 0;	/* Gee, mktime() is nice */
+					tmtmp.tm_mday = spev[v1].getev(tmtmp.tm_year +
+					    vwd + TM_YEAR_BASE);
+				} else if (vwd) {
+					v1 = vwd;
+					variable_weekday(&v1, tmtmp.tm_mon + 1,
+					    tmtmp.tm_year + TM_YEAR_BASE);
+					tmtmp.tm_mday = v1;
+				} else {
+				/* Need the following to keep Feb 29 from
+				 * becoming Mar 1 */
+				tmtmp.tm_mday = dayp;
+				tmtmp.tm_mon = monthp - 1;
+				}
+				break;
+			}
+			/* How many days apart are we */
+			if ((ttmp = mktime(&tmtmp)) == -1)
+				warnx("time out of range: %s", endp);
+			else {
+				tdiff = difftime(ttmp, f_time)/ SECSPERDAY;
+				if (tdiff <= offset + f_dayAfter) {
+					if (tdiff >=  0) {
+					if ((tmp = malloc(sizeof(struct match))) == NULL)
+						errx(1, "cannot allocate memory");
+					tmp->when = ttmp;
+					if (strftime(tmp->print_date,
+					    sizeof(tmp->print_date),
+					/*    "%a %b %d", &tm);  Skip weekdays */
+					    "%b %d", &tmtmp) == 0)
+						tmp->print_date[sizeof(tmp->print_date) - 1] = '\0';
+					tmp->var   = varp;
+					tmp->next  = NULL;
+					if (tmp2)
+						tmp2->next = tmp;
+					else
+						matches = tmp;
+					tmp2 = tmp;
+					v2 = (i == 1) ? 1 : 0;
+					}
+				} else
+					i = 2; /* No point checking in the future */
+			}
+		} while (v2 != 0);
 	}
-	return (NULL);
+	return (matches);
 }
 
 
@@ -450,21 +584,17 @@
 
 	offset = strlen(s);
 
-
 	/* Sun+1 or Wednesday-2
 	 *    ^              ^   */
 
 	/* printf ("x: %s %s %d\n", s, s + offset - 2, offset); */
 	switch(*(s + offset - 2)) {
 	case '-':
-	    return(-(atoi(s + offset - 1)));
-	    break;
 	case '+':
-	    return(atoi(s + offset - 1));
+	    return(atoi(s + offset - 2));
 	    break;
 	}
 
-
 	/*
 	 * some aliases: last, first, second, third, fourth
 	 */
@@ -481,7 +611,63 @@
 	else if (offset > 6 && !strcasecmp(s + offset - 6, "fourth"))
 	    return(+4);
 
-
 	/* no offset detected */
 	return(0);
+}
+
+
+int
+foy(year)
+	int year;
+{
+	/* 0-6; what weekday Jan 1 is */
+	year--;
+	return ((1 - year/100 + year/400 + (int)(365.25 * year)) % 7);
+}
+
+
+
+void
+variable_weekday(day, month, year)
+	int *day, month, year;
+{
+	int v1, v2;
+	int *cumdays;
+	int day1;
+
+	if (isleap(year))
+		cumdays = daytab[1];
+	else
+		cumdays = daytab[0];
+	day1 = foy(year);
+	/* negative offset; last, -4 .. -1 */
+	if (*day < 0) {
+		v1 = *day/10 - 1;          /* offset -4 ... -1 */
+		*day = 10 + (*day % 10);    /* day 1 ... 7 */
+
+		/* which weekday the end of the month is (1-7) */
+		v2 = (cumdays[month + 1] + day1) % 7 + 1;
+
+		/* and subtract enough days */
+		*day = cumdays[month + 1] - cumdays[month] +
+		    (v1 + 1) * 7 - (v2 - *day + 7) % 7;
+#if DEBUG
+		fprintf(stderr, "\nMonth %d ends on weekday %d\n", month, v2);
+#endif
+	}
+
+	/* first, second ... +1 ... +5 */
+	else {
+		v1 = *day/10;        /* offset */
+		*day = *day % 10;
+
+		/* which weekday the first of the month is (1-7) */
+		v2 = (cumdays[month] + 1 + day1) % 7 + 1;
+
+		/* and add enough days */
+		*day = 1 + (v1 - 1) * 7 + (*day - v2 + 7) % 7;
+#if DEBUG
+		fprintf(stderr, "\nMonth %d starts on weekday %d\n", month, v2);
+#endif
+	}
 }