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diff --git a/libical/src/libical/icalrecur.h b/libical/src/libical/icalrecur.h
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+/* -*- Mode: C -*- */
+/*======================================================================
+ FILE: icalrecur.h
+ CREATOR: eric 20 March 2000
+
+
+ (C) COPYRIGHT 2000, Eric Busboom, http://www.softwarestudio.org
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of either: 
+
+    The LGPL as published by the Free Software Foundation, version
+    2.1, available at: http://www.fsf.org/copyleft/lesser.html
+
+  Or:
+
+    The Mozilla Public License Version 1.0. You may obtain a copy of
+    the License at http://www.mozilla.org/MPL/
+
+How to use: 
+
+1) Get a rule and a start time from a component
+        icalproperty rrule;
+        struct icalrecurrencetype recur;
+        struct icaltimetype dtstart;
+
+        rrule = icalcomponent_get_first_property(comp,ICAL_RRULE_PROPERTY);
+        recur = icalproperty_get_rrule(rrule);
+        start = icalproperty_get_dtstart(dtstart);
+
+Or, just make them up: 
+        recur = icalrecurrencetype_from_string("FREQ=YEARLY;BYDAY=SU,WE");
+        dtstart = icaltime_from_string("19970101T123000")
+
+2) Create an iterator
+        icalrecur_iterator* ritr;
+        ritr = icalrecur_iterator_new(recur,start);
+
+3) Iterator over the occurrences
+        struct icaltimetype next;
+        while (next = icalrecur_iterator_next(ritr) 
+               && !icaltime_is_null_time(next){
+                Do something with next
+        }
+
+Note that that the time returned by icalrecur_iterator_next is in
+whatever timezone that dtstart is in.
+
+======================================================================*/
+
+#ifndef ICALRECUR_H
+#define ICALRECUR_H
+
+#include <time.h>
+#include "icaltime.h"
+
+/***********************************************************************
+ * Recurrance enumerations
+**********************************************************************/
+
+typedef enum icalrecurrencetype_frequency
+{
+    /* These enums are used to index an array, so don't change the
+       order or the integers */
+
+    ICAL_SECONDLY_RECURRENCE=0,
+    ICAL_MINUTELY_RECURRENCE=1,
+    ICAL_HOURLY_RECURRENCE=2,
+    ICAL_DAILY_RECURRENCE=3,
+    ICAL_WEEKLY_RECURRENCE=4,
+    ICAL_MONTHLY_RECURRENCE=5,
+    ICAL_YEARLY_RECURRENCE=6,
+    ICAL_NO_RECURRENCE=7
+
+} icalrecurrencetype_frequency;
+
+typedef enum icalrecurrencetype_weekday
+{
+    ICAL_NO_WEEKDAY,
+    ICAL_SUNDAY_WEEKDAY,
+    ICAL_MONDAY_WEEKDAY,
+    ICAL_TUESDAY_WEEKDAY,
+    ICAL_WEDNESDAY_WEEKDAY,
+    ICAL_THURSDAY_WEEKDAY,
+    ICAL_FRIDAY_WEEKDAY,
+    ICAL_SATURDAY_WEEKDAY
+} icalrecurrencetype_weekday;
+
+enum {
+    ICAL_RECURRENCE_ARRAY_MAX = 0x7f7f,
+    ICAL_RECURRENCE_ARRAY_MAX_BYTE = 0x7f
+};
+
+
+
+/********************** Recurrence type routines **************/
+
+/* See RFC 2445 Section 4.3.10, RECUR Value, for an explaination of
+   the values and fields in struct icalrecurrencetype */
+
+#define ICAL_BY_SECOND_SIZE 61
+#define ICAL_BY_MINUTE_SIZE 61
+#define ICAL_BY_HOUR_SIZE 25
+#define ICAL_BY_DAY_SIZE 364 /* 7 days * 52 weeks */
+#define ICAL_BY_MONTHDAY_SIZE 32
+#define ICAL_BY_YEARDAY_SIZE 367
+#define ICAL_BY_WEEKNO_SIZE 54
+#define ICAL_BY_MONTH_SIZE 13
+#define ICAL_BY_SETPOS_SIZE 367
+
+/* Main struct for holding digested recurrence rules */
+struct icalrecurrencetype 
+{
+        icalrecurrencetype_frequency freq;
+
+
+        /* until and count are mutually exclusive. */
+               struct icaltimetype until; 
+        int count;
+
+        short interval;
+        
+        icalrecurrencetype_weekday week_start;
+        
+        /* The BY* parameters can each take a list of values. Here I
+         * assume that the list of values will not be larger than the
+         * range of the value -- that is, the client will not name a
+         * value more than once. 
+         
+         * Each of the lists is terminated with the value
+         * ICAL_RECURRENCE_ARRAY_MAX unless the the list is full.
+         */
+
+        short by_second[ICAL_BY_SECOND_SIZE];
+        short by_minute[ICAL_BY_MINUTE_SIZE];
+        short by_hour[ICAL_BY_HOUR_SIZE];
+        short by_day[ICAL_BY_DAY_SIZE]; /* Encoded value, see below */
+        short by_month_day[ICAL_BY_MONTHDAY_SIZE];
+        short by_year_day[ ICAL_BY_YEARDAY_SIZE];
+        short by_week_no[ICAL_BY_WEEKNO_SIZE];
+        short by_month[ICAL_BY_MONTH_SIZE];
+        short by_set_pos[ICAL_BY_SETPOS_SIZE];
+};
+
+
+void icalrecurrencetype_clear(struct icalrecurrencetype *r);
+
+/* The 'day' element of the by_day array is encoded to allow
+representation of both the day of the week ( Monday, Tueday), but also
+the Nth day of the week ( First tuesday of the month, last thursday of
+the year) These routines decode the day values */
+
+/* 1 == Monday, etc. */
+enum icalrecurrencetype_weekday icalrecurrencetype_day_day_of_week(short day);
+
+/* 0 == any of day of week. 1 == first, 2 = second, -2 == second to last, etc */
+short icalrecurrencetype_day_position(short day);
+
+
+/***********************************************************************
+ * Recurrance rule parser
+**********************************************************************/
+
+/* Convert between strings ans recurrencetype structures. */
+struct icalrecurrencetype icalrecurrencetype_from_string(const char* str);
+char* icalrecurrencetype_as_string(struct icalrecurrencetype *recur);
+
+
+/********** recurrence iteration routines ********************/
+
+typedef void icalrecur_iterator;
+
+/* Create a new recurrence rule iterator */
+icalrecur_iterator* icalrecur_iterator_new(struct icalrecurrencetype rule, 
+                                           struct icaltimetype dtstart);
+
+/* Get the next occurrence from an iterator */
+struct icaltimetype icalrecur_iterator_next(icalrecur_iterator*);
+
+/* Free the iterator */
+void icalrecur_iterator_free(icalrecur_iterator*);
+
+/* Fills array up with at most 'count' time_t values, each
+   representing an occurrence time in seconds past the POSIX epoch */
+int icalrecur_expand_recurrence(char* rule, time_t start, 
+                                int count, time_t* array);
+
+
+#endif