}
-// Check to see if two events overlap. Returns nonzero if they do.
-// (This function is used in both Citadel and WebCit. If you change it in
-// one place, change it in the other. Better yet, put it in a library.)
-int ical_ctdl_is_overlap(
- struct icaltimetype t1start,
- struct icaltimetype t1end,
- struct icaltimetype t2start,
- struct icaltimetype t2end
-) {
- if (icaltime_is_null_time(t1start)) return(0);
- if (icaltime_is_null_time(t2start)) return(0);
-
- // if either event lacks end time, assume end = start
- if (icaltime_is_null_time(t1end)) {
- memcpy(&t1end, &t1start, sizeof(struct icaltimetype));
- }
- else {
- if (t1end.is_date && icaltime_compare(t1start, t1end)) {
-
- // the end date is non-inclusive so adjust it by one
- // day because our test is inclusive, note that a day is
- // not too much because we are talking about all day
- // events
- // if start = end we assume that nevertheless the whole
- // day is meant
-
- icaltime_adjust(&t1end, -1, 0, 0, 0);
- }
- }
-
- if (icaltime_is_null_time(t2end))
- memcpy(&t2end, &t2start, sizeof(struct icaltimetype));
- else {
- if (t2end.is_date && icaltime_compare(t2start, t2end)) {
- icaltime_adjust(&t2end, -1, 0, 0, 0);
- }
- }
-
- // First, check for all-day events
- if (t1start.is_date || t2start.is_date) {
- // If event 1 ends before event 2 starts, we're in the clear.
- if (icaltime_compare_date_only(t1end, t2start) < 0) return(0);
-
- // If event 2 ends before event 1 starts, we're also ok.
- if (icaltime_compare_date_only(t2end, t1start) < 0) return(0);
-
- return(1);
- }
-
- // syslog(LOG_DEBUG, "Comparing t1start %d:%d t1end %d:%d t2start %d:%d t2end %d:%d",
- // t1start.hour, t1start.minute, t1end.hour, t1end.minute,
- // t2start.hour, t2start.minute, t2end.hour, t2end.minute);
-
- // Now check for overlaps using date *and* time.
-
- // If event 1 ends before event 2 starts, we're in the clear.
- if (icaltime_compare(t1end, t2start) <= 0) return(0);
- // syslog(LOG_DEBUG, "calendar: first passed");
-
- // If event 2 ends before event 1 starts, we're also ok.
- if (icaltime_compare(t2end, t1start) <= 0) return(0);
- // syslog(LOG_DEBUG, "calendar: second passed");
-
- // Otherwise, they overlap.
- return(1);
-}
-
-
// Phase 6 of "hunt for conflicts"
// called by ical_conflicts_phase5()
//