merged in some new stuff from libical CVS. (icalrecur_add_byrules): If no

2001-06-13  Damon Chaplin  <damon@ximian.com>

	* src/libical/icalrecur.c: merged in some new stuff from libical CVS.
	(icalrecur_add_byrules): If no sign is given set sign to 1 (i.e.
	default to positive).
	(icalrecur_iterator_new): when setting up the year days array, handle
	the case where a year has no occurrences and we have to skip it.
	Also initialize the last.day and last.month fields.
	(expand_by_day): set the last day of the year explicitly rather than
	adding 1 to year and subtracting 1 from day. It is more efficient,
	and less prone to bugs. Also rewrote a bit.
	(expand_year_days): added code to handle BY_MONTH_DAY and BY_DAY +
	BY_MONTH_DAY, and rewrote code to handle BY_DAY + BY_MONTH.
	(next_year): handled the case where there are no occurrences in the
	year.

	* src/libical/icaltime.c (icaltime_adjust): new function to adjust a
	time by a number of days/hours/minutes/seconds.
	(icaltime_day_of_week): rewrote using a single call to mktime().
	(icaltime_day_of_year): rewrote using a single call to mktime().
	(icaltime_from_day_of_year): rewrote in a simpler way. The old version
	had a bug in it.

	* src/libical/icaltime.h (struct icaltimetype): added is_daylight
	flag, so we can try to distinguish between standard and daylight time
	when the clocks go back. Though this doesn't always resolve the
	ambiguity.

	* src/libical/icalcomponent.c: added some stuff to handle timezone
	data connected to the calendar component. Unfinished.

	* src/libical/icalyacc.y: merged in a fix from sourceforge CVS version
	of libical, so we can handle -ve UTC offsets.

	* src/libical/Makefile.am (CPPFLAGS): added PACKAGE_DATA_DIR define
	for finding the VTIMEZONE files.
	(libical_la_SOURCES): added icalarray.[hc] and icaltimezone.[hc].
	(COMBINEDHEADERS): added icalarray.h and icaltimezone.h to the headers
	to be combined into ical.h.

svn path=/trunk/; revision=10220

6 files changed, 398 insertions, 89 deletions

diff --git a/libical/src/libical/Makefile.am b/libical/src/libical/Makefile.am
index 5c2200c7f0..9e1a6da9ca 100644
--- a/libical/src/libical/Makefile.am
+++ b/libical/src/libical/Makefile.am
@@ -2,7 +2,7 @@
 #  FILE: Makefile.am
 #  CREATOR: eric 
 #  
-#  $Id: Makefile.am,v 1.29 2001/05/16 07:16:31 jpr Exp $
+#  $Id: Makefile.am,v 1.30 2001/06/14 02:50:46 damon Exp $
 #
 #
 # (C) COPYRIGHT 2000, Eric Busboom, http://www.softwarestudio.org
@@ -36,6 +36,8 @@ YFLAGS = -d -v -t -pical_yy
 LFLAGS = -Pical_yy
 LEX_OUTPUT_ROOT = lex.ical_yy
 
+CPPFLAGS = -DPACKAGE_DATA_DIR=\""$(datadir)/$(PACKAGE)"\"
+
 all: ical.h
 
 INCLUDES =			\
@@ -48,6 +50,8 @@ libical_la_LDFLAGS = -version-info 0:0:0
 
 libical_la_SOURCES =		\
 	$(BUILT_SOURCES)	\
+	icalarray.c		\
+	icalarray.h		\
 	icalattendee.h		\
 	icalattendee.c		\
 	icalcomponent.c		\
@@ -73,6 +77,8 @@ libical_la_SOURCES =		\
 	icalrestriction.h	\
 	icaltime.c		\
 	icaltime.h		\
+	icaltimezone.c		\
+	icaltimezone.h		\
 	icalduration.h		\
 	icalduration.c		\
 	icalperiod.h		\
@@ -114,7 +120,9 @@ COMBINEDHEADERS =					\
 	$(top_srcdir)/src/libical/icalproperty.h	\
 	$(top_srcdir)/src/libical/icalattendee.h	\
 	$(top_srcdir)/src/libical/pvl.h			\
+	$(top_srcdir)/src/libical/icalarray.h		\
 	$(top_srcdir)/src/libical/icalcomponent.h	\
+	$(top_srcdir)/src/libical/icaltimezone.h	\
 	$(top_srcdir)/src/libical/icalparser.h		\
 	$(top_srcdir)/src/libical/icalmemory.h		\
 	$(top_srcdir)/src/libical/icalerror.h		\
diff --git a/libical/src/libical/icalcomponent.c b/libical/src/libical/icalcomponent.c
index c28c972007..ee4ec54f30 100644
--- a/libical/src/libical/icalcomponent.c
+++ b/libical/src/libical/icalcomponent.c
@@ -33,6 +33,8 @@
 #include "icalmemory.h"
 #include "icalenums.h"
 #include "icaltime.h"
+#include "icalarray.h"
+#include "icaltimezone.h"
 #include "icalduration.h"
 #include "icalperiod.h"
 #include "icalparser.h"
@@ -55,6 +57,7 @@ struct icalcomponent_impl
 	pvl_list components;
 	pvl_elem component_iterator;
 	icalcomponent* parent;
+	icalarray* timezones;
 };
 
 /* icalproperty functions that only components get to use */
@@ -65,6 +68,8 @@ void icalcomponent_add_children(struct icalcomponent_impl *impl,va_list args);
 icalcomponent* icalcomponent_new_impl (icalcomponent_kind kind);
 int icalcomponent_property_sorter(void *a, void *b);
 
+static void icalcomponent_rename_tzids_callback(icalparameter *param,
+						void *data);
 
 void icalcomponent_add_children(struct icalcomponent_impl *impl,va_list args)
 {
@@ -108,6 +113,7 @@ icalcomponent_new_impl (icalcomponent_kind kind)
     comp->component_iterator = 0;
     comp->x_name = 0;
     comp->parent = 0;
+    comp->timezones = icaltimezone_array_new ();
 
     return comp;
 }
@@ -219,6 +225,8 @@ icalcomponent_free (icalcomponent* component)
 	    free(c->x_name);
 	}
 
+	icalarray_free (c->timezones);
+
 	c->kind = ICAL_NO_COMPONENT;
 	c->properties = 0;
 	c->property_iterator = 0;
@@ -226,9 +234,11 @@ icalcomponent_free (icalcomponent* component)
 	c->component_iterator = 0;
 	c->x_name = 0;	
 	c->id[0] = 'X';
+	c->timezones = NULL;
 
 	free(c);
     }
+
 }
 
 char*
@@ -531,6 +541,10 @@ icalcomponent_add_component (icalcomponent* parent, icalcomponent* child)
     cimpl->parent = parent;
 
     pvl_push(impl->components,child);
+
+    /* If the new component is a VTIMEZONE, add it to our array. */
+    if (cimpl->kind == ICAL_VTIMEZONE_COMPONENT)
+      icaltimezone_array_append_from_vtimezone (cimpl->timezones, child);
 }
 
 
@@ -546,6 +560,20 @@ icalcomponent_remove_component (icalcomponent* parent, icalcomponent* child)
    impl = (struct icalcomponent_impl*)parent;
    cimpl = (struct icalcomponent_impl*)child;
    
+    /* If the component is a VTIMEZONE, remove it from our array as well. */
+    if (cimpl->kind == ICAL_VTIMEZONE_COMPONENT) {
+	icaltimezone *zone;
+	int i;
+
+        for (i = 0; i < impl->timezones->num_elements; i++) {
+	    zone = icalarray_element_at (impl->timezones, i);
+	    if (icaltimezone_get_component (zone) == child) {
+	        icalarray_remove_element_at (impl->timezones, i);
+		break;
+	    }
+	}
+    }
+
    for( itr = pvl_head(impl->components);
 	itr != 0;
 	itr = next_itr)
@@ -1485,3 +1513,99 @@ icalcomponent* icalcomponent_new_xdaylight()
 {
     return icalcomponent_new(ICAL_XDAYLIGHT_COMPONENT);
 }
+
+/* Calls the given function for each TZID parameter found in the component. */
+void icalcomponent_foreach_tzid(icalcomponent* comp,
+				void (*callback)(icalparameter *param, void *data),
+				void *callback_data)
+{
+    icalproperty *prop;
+    icalproperty_kind kind;
+    icalparameter *param;
+    icalcomponent *child;
+
+    /* First rename any TZID parameters used in this component. */
+    prop = icalcomponent_get_first_property (comp, ICAL_ANY_PROPERTY);
+    while (prop) {
+        kind = icalproperty_isa (prop);
+
+      /* These are the only properties that can have a TZID. Note that
+	 COMPLETED, CREATED, DTSTAMP & LASTMODIFIED must be in UTC. */
+      if (kind == ICAL_DTSTART_PROPERTY || kind == ICAL_DTEND_PROPERTY
+	  || kind == ICAL_DUE_PROPERTY || kind == ICAL_EXDATE_PROPERTY
+	  || kind == ICAL_RDATE_PROPERTY) {
+	param = icalproperty_get_first_parameter (prop, ICAL_TZID_PARAMETER);
+	if (param)
+	    (*callback) (param, callback_data);
+      }
+
+      prop = icalcomponent_get_next_property (comp, ICAL_ANY_PROPERTY);
+    }
+
+    /* Now recursively rename child components. */
+    child = icalcomponent_get_first_component (comp, ICAL_ANY_COMPONENT);
+    while (child) {
+        icalcomponent_foreach_tzid (child, callback, callback_data);
+        child = icalcomponent_get_next_component (comp, ICAL_ANY_COMPONENT);
+    }
+}
+
+
+/* Renames all references to the given TZIDs to a new name. rename_table
+   contains pairs of strings - a current TZID, and the new TZID to rename it
+   to. */
+void icalcomponent_rename_tzids(icalcomponent* comp, icalarray* rename_table)
+{
+    icalcomponent_foreach_tzid (comp, icalcomponent_rename_tzids_callback,
+				rename_table);
+}
+
+
+static void icalcomponent_rename_tzids_callback(icalparameter *param, void *data)
+{
+    icalarray *rename_table = data;
+    const char *tzid;
+    int i;
+
+    tzid = icalparameter_get_tzid (param);
+    if (!tzid)
+        return;
+
+    /* Step through the rename table to see if the current TZID matches
+       any of the ones we want to rename. */
+    for (i = 0; i < rename_table->num_elements - 1; i += 2) {
+        if (!strcmp (tzid, icalarray_element_at (rename_table, i)))
+	    icalparameter_set_tzid (param, icalarray_element_at (rename_table, i + 1));
+    }
+}
+
+
+/* Returns the icaltimezone from the component corresponding to the given
+   TZID, or NULL if the component does not have a corresponding VTIMEZONE. */
+icaltimezone* icalcomponent_get_timezone(icalcomponent* comp, const char *tzid)
+{
+    struct icalcomponent_impl *impl;
+    icaltimezone *zone;
+    int lower, upper, middle, cmp;
+
+    impl = (struct icalcomponent_impl*)comp;
+
+    /* Do a simple binary search. */
+    lower = middle = 0;
+    upper = impl->timezones->num_elements;
+
+    while (lower < upper) {
+	middle = (lower + upper) >> 1;
+	zone = icalarray_element_at (impl->timezones, middle);
+	cmp = strcmp (tzid, icaltimezone_get_tzid (zone));
+	if (cmp == 0)
+	    return zone;
+	else if (cmp < 0)
+	    upper = middle;
+	else
+	    lower = middle + 1;
+    }
+
+    return NULL;
+}
+
diff --git a/libical/src/libical/icalrecur.c b/libical/src/libical/icalrecur.c
index 51fdf63a79..99ebf022f6 100644
--- a/libical/src/libical/icalrecur.c
+++ b/libical/src/libical/icalrecur.c
@@ -280,6 +280,8 @@ void icalrecur_add_byrules(struct icalrecur_parser *parser, short *array,
 	} else if (*t == '+'){
 	    sign = 1;
 	    t++;
+	} else {
+	    sign = 1;
 	}
 
 	v = atoi(t) * sign ;
@@ -904,7 +906,20 @@ icalrecur_iterator* icalrecur_iterator_new(struct icalrecurrencetype rule,
     /* For YEARLY rule, begin by setting up the year days array */
 
     if(impl->rule.freq == ICAL_YEARLY_RECURRENCE){
-        expand_year_days(impl,impl->last.year);
+        struct icaltimetype next;
+
+	for (;;) {
+	    expand_year_days(impl,impl->last.year);
+	    if (impl->days[0] != ICAL_RECURRENCE_ARRAY_MAX)
+	        break;
+	    increment_year(impl,impl->rule.interval);
+	}
+
+        /* Copy the first day into last. */
+	next = icaltime_from_day_of_year(impl->days[0], impl->last.year);
+    
+	impl->last.day =  next.day;
+	impl->last.month =  next.month;
     } 
 
 
@@ -1618,13 +1633,14 @@ int next_week(struct icalrecur_iterator_impl* impl)
 }
 
 
+/* Expand the BYDAY rule part and return a pointer to a newly allocated list of days. */
 pvl_list expand_by_day(struct icalrecur_iterator_impl* impl,short year)
 {
     /* Try to calculate each of the occurrences. */
     int i;
     pvl_list days_list = pvl_newlist();
 
-    short start_dow, end_dow, end_year_day, start_doy;
+    short start_dow, end_dow, end_year_day;
     struct icaltimetype tmp = impl->last;
     
     tmp.year= year;
@@ -1632,35 +1648,34 @@ pvl_list expand_by_day(struct icalrecur_iterator_impl* impl,short year)
     tmp.day = 1;
     tmp.is_date = 1;
     
+    /* Find the day that 1st Jan falls on, 1 (Sun) to 7 (Sat). */
     start_dow = icaltime_day_of_week(tmp);
-    start_doy =  icaltime_start_doy_of_week(tmp);
     
     /* Get the last day of the year*/
-    tmp.year++;
-    tmp = icaltime_normalize(tmp);
-    tmp.day--;
-    tmp = icaltime_normalize(tmp);
-    
+    tmp.year= year;
+    tmp.month = 12;
+    tmp.day = 31;
+    tmp.is_date = 1;
+
     end_dow =  icaltime_day_of_week(tmp);
     end_year_day = icaltime_day_of_year(tmp);
-    
+
     for(i = 0; BYDAYPTR[i] != ICAL_RECURRENCE_ARRAY_MAX; i++){
+        /* This is 1 (Sun) to 7 (Sat). */
         short dow = 
             icalrecurrencetype_day_day_of_week(BYDAYPTR[i]);  
         short pos =  icalrecurrencetype_day_position(BYDAYPTR[i]);
         
         if(pos == 0){
-            /* add all of the days of the year with this day-of-week*/
-            int week;
-            for(week = 0; week < 52 ; week ++){
-                short doy = start_doy + (week * 7) + dow-1;
-                
-                if(doy > end_year_day){
-                    break;
-                } else {
-                    pvl_push(days_list,(void*)(int)doy);
-                }
-            } 
+            /* The day was specified without a position -- it is just
+               a bare day of the week ( BYDAY=SU) so add all of the
+               days of the year with this day-of-week*/
+            int doy, tmp_start_doy;
+
+	    tmp_start_doy = ((dow + 7 - start_dow) % 7) + 1;
+
+            for (doy = tmp_start_doy; doy <= end_year_day; doy += 7)
+		pvl_push(days_list,(void*)(int)doy);
             
         } else if ( pos > 0) {
             int first;
@@ -1674,7 +1689,7 @@ pvl_list expand_by_day(struct icalrecur_iterator_impl* impl,short year)
             pvl_push(days_list,(void*)(first+  (pos-1) * 7));
             
         } else { /* pos < 0 */ 
-            assert(0);
+            icalerror_set_errno(ICAL_UNIMPLEMENTED_ERROR);
         }
     }
 
@@ -1693,6 +1708,8 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
     struct icaltimetype t;
     int flags;
 
+    t = icaltime_null_time();
+
 #define HBD(x) has_by_data(impl,x)
 
     t.is_date = 1; /* Needed to make day_of_year routines work property */
@@ -1706,12 +1723,12 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
         (HBD(BY_MONTH) ? 1<<BY_MONTH : 0) + 
         (HBD(BY_YEAR_DAY) ? 1<<BY_YEAR_DAY : 0);
 
-
+    
     switch(flags) {
-
+        
     case 0: {
         /* FREQ=YEARLY; */
-
+        
         break;
     }
     case 1<<BY_MONTH: {
@@ -1737,7 +1754,21 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
 
     case 1<<BY_MONTH_DAY:  {
         /* FREQ=YEARLY; BYMONTHDAY=1,15*/
-        assert(0);
+        for(k=0;impl->by_ptrs[BY_MONTH_DAY][k]!=ICAL_RECURRENCE_ARRAY_MAX;k++)
+            {
+                short month_day = impl->by_ptrs[BY_MONTH_DAY][k];
+                short doy;
+
+                t = impl->dtstart;
+		t.day = month_day;
+		t.year = year;
+		t.is_date = 1;
+
+		doy = icaltime_day_of_year(t);
+
+		impl->days[days_index++] = doy;
+
+            }
         break;
     }
 
@@ -1757,7 +1788,6 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
 		t.is_date = 1;
 
 		doy = icaltime_day_of_year(t);
-
 		impl->days[days_index++] = doy;
 
             }
@@ -1779,13 +1809,15 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
 
         dow = icaltime_day_of_week(t);
 	/* HACK Not finished */ 
+
+        icalerror_set_errno(ICAL_UNIMPLEMENTED_ERROR);
 	
         break;
     }
 
     case (1<<BY_WEEK_NO) + (1<<BY_MONTH_DAY): {
         /*FREQ=YEARLY; WEEKNO=20,50; BYMONTH= 6,11 */
-        assert(0);
+        icalerror_set_errno(ICAL_UNIMPLEMENTED_ERROR);
         break;
     }
 
@@ -1801,6 +1833,8 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
             impl->days[days_index++] = day;
         }
 
+        pvl_free(days);
+
         break;
     }
 
@@ -1811,38 +1845,86 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
         for(j=0;impl->by_ptrs[BY_MONTH][j]!=ICAL_RECURRENCE_ARRAY_MAX;j++){
 	    short month = impl->by_ptrs[BY_MONTH][j];
 	    short days_in_month = icaltime_days_in_month(month,year);
+	    short first_dow, last_dow, doy_offset;
 		
 	    struct icaltimetype t;
 	    memset(&t,0,sizeof(struct icaltimetype));
-	    t.day = 1;
 	    t.year = year;
 	    t.month = month;
+	    t.day = 1;
 	    t.is_date = 1;
 	    
-	    for(t.day = 1; t.day <=days_in_month; t.day++){
-		
-		short current_dow = icaltime_day_of_week(t);
+	    first_dow = icaltime_day_of_week(t);
+
+	    /* This holds the day offset used to calculate the day of the year
+	       from the month day. Just add the month day to this. */
+	    doy_offset = icaltime_day_of_year(t) - 1;
 		
-		for(k=0;impl->by_ptrs[BY_DAY][k]!=ICAL_RECURRENCE_ARRAY_MAX;k++){
-		    
-		    enum icalrecurrencetype_weekday dow =
-			icalrecurrencetype_day_day_of_week(impl->by_ptrs[BY_DAY][k]);
-		    
-		    if(current_dow == dow){
-			short doy = icaltime_day_of_year(t);
-			/* HACK, incomplete Nth day of week handling */
-			impl->days[days_index++] = doy;
-			
-		    }
+	    t.day = days_in_month;
+	    last_dow = icaltime_day_of_week(t);
+
+	    for(k=0;impl->by_ptrs[BY_DAY][k]!=ICAL_RECURRENCE_ARRAY_MAX;k++){
+	        short day_coded = impl->by_ptrs[BY_DAY][k];
+		enum icalrecurrencetype_weekday dow =
+		  icalrecurrencetype_day_day_of_week(day_coded);
+		short pos = icalrecurrencetype_day_position(day_coded);  
+		short first_matching_day, last_matching_day, day, month_day;
+
+		/* Calculate the first day in the month with the given weekday,
+		   and the last day. */
+		first_matching_day = ((dow + 7 - first_dow) % 7) + 1;
+		last_matching_day = days_in_month - ((last_dow + 7 - dow) % 7);
+
+		if (pos == 0) {
+		    /* Add all of instances of the weekday within the month. */
+		  for (day = first_matching_day; day <= days_in_month; day += 7)
+		      impl->days[days_index++] = doy_offset + day;
+
+		} else if (pos > 0) {
+		    /* Add the nth instance of the weekday within the month. */
+		    month_day = first_matching_day + (pos - 1) * 7;
+
+		    if (month_day <= days_in_month)
+		        impl->days[days_index++] = doy_offset + month_day;
+
+		} else {
+		    /* Add the -nth instance of the weekday within the month.*/
+		    month_day = last_matching_day + (pos + 1) * 7;
+
+		    if (month_day > 0)
+		        impl->days[days_index++] = doy_offset + month_day;
 		}
-            }
+	    }
         }
         break;
     }
 
     case (1<<BY_DAY) + (1<<BY_MONTH_DAY) : {
         /*FREQ=YEARLY; BYDAY=TH,20MO,-10FR; BYMONTHDAY=1,15*/
-        assert(0);
+
+        int days_index = 0;
+        pvl_elem itr;
+        pvl_list days = expand_by_day(impl,year);
+
+        for(itr=pvl_head(days);itr!=0;itr=pvl_next(itr)){
+            short day = (short)(int)pvl_data(itr);
+            struct icaltimetype tt; 
+            short i,j;
+            
+            tt = icaltime_from_day_of_year(day,year);
+            
+            for(j = 0; BYMDPTR[j]!=ICAL_RECURRENCE_ARRAY_MAX; j++){
+                    short mday = BYMDPTR[j];
+                    
+                    if(tt.day == mday){
+                        impl->days[days_index++] = day;
+                    }
+            }
+            
+        }
+
+        pvl_free(days);
+       
         break;
     }
 
@@ -1873,6 +1955,8 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
 
         }
 
+        pvl_free(days);
+
        break;
 
     }
@@ -1900,12 +1984,14 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
             }
                     
         }
+
+        pvl_free(days);
         break;
     }
 
     case (1<<BY_DAY) + (1<<BY_WEEK_NO) + (1<<BY_MONTH_DAY): {
         /*FREQ=YEARLY; BYDAY=TH,20MO,-10FR;  WEEKNO=20,50; BYMONTHDAY=1,15*/
-        assert(0);
+        icalerror_set_errno(ICAL_UNIMPLEMENTED_ERROR);
         break;
     }
 
@@ -1918,7 +2004,7 @@ int expand_year_days(struct icalrecur_iterator_impl* impl,short year)
     }
 
     default: {
-        assert(0);
+        icalerror_set_errno(ICAL_UNIMPLEMENTED_ERROR);
         break;
     }
 
@@ -1938,8 +2024,13 @@ int next_year(struct icalrecur_iterator_impl* impl)
 
     if (impl->days[++impl->days_index] == ICAL_RECURRENCE_ARRAY_MAX){
 	impl->days_index = 0;
-	increment_year(impl,impl->rule.interval);
-        expand_year_days(impl,impl->last.year);
+
+	for (;;) {
+	  increment_year(impl,impl->rule.interval);
+	  expand_year_days(impl,impl->last.year);
+	  if (impl->days[0] != ICAL_RECURRENCE_ARRAY_MAX)
+	    break;
+	}
     }
 
     next = icaltime_from_day_of_year(impl->days[impl->days_index],impl->last.year);
diff --git a/libical/src/libical/icaltime.c b/libical/src/libical/icaltime.c
index d5b228b089..6a3859c094 100644
--- a/libical/src/libical/icaltime.c
+++ b/libical/src/libical/icaltime.c
@@ -389,17 +389,19 @@ short icaltime_days_in_month(short month,short year)
 
 /* 1-> Sunday, 7->Saturday */
 short icaltime_day_of_week(struct icaltimetype t){
+    struct tm stm;
 
-    time_t tt = icaltime_as_timet(t);
-    struct tm *tm;
+    stm.tm_year = t.year - 1900;
+    stm.tm_mon = t.month - 1;
+    stm.tm_mday = t.day;
+    stm.tm_hour = 0;
+    stm.tm_min = 0;
+    stm.tm_sec = 0;
+    stm.tm_isdst = -1;
 
-    if(t.is_utc == 1){
-	tm = gmtime(&tt);
-    } else {
-	tm = localtime(&tt);
-    }
+    mktime (&stm);
 
-    return tm->tm_wday+1;
+    return stm.tm_wday + 1;
 }
 
 /* Day of the year that the first day of the week (Sunday) is on  */
@@ -450,41 +452,49 @@ short icaltime_week_number(struct icaltimetype ictt)
 
 
 short icaltime_day_of_year(struct icaltimetype t){
-    time_t tt = icaltime_as_timet(t);
-    struct tm *stm;
+    struct tm stm;
 
-    if(t.is_utc==1){
-	stm = gmtime(&tt);
-    } else {
-	stm = localtime(&tt);
-    }
+    stm.tm_year = t.year - 1900;
+    stm.tm_mon = t.month - 1;
+    stm.tm_mday = t.day;
+    stm.tm_hour = 0;
+    stm.tm_min = 0;
+    stm.tm_sec = 0;
+    stm.tm_isdst = -1;
 
-    return stm->tm_yday+1;
-    
+    mktime (&stm);
+
+    return stm.tm_yday + 1;
 }
 
 /* Jan 1 is day #1, not 0 */
 struct icaltimetype icaltime_from_day_of_year(short doy,  short year)
 {
-    struct tm stm; 
-    time_t tt;
-    char *old_tz = set_tz("UTC");
-
-    /* Get the time of january 1 of this year*/
-    memset(&stm,0,sizeof(struct tm)); 
-    stm.tm_year = year-1900;
-    stm.tm_mday = 1;
-
-    tt = mktime(&stm);
-    unset_tz(old_tz);
-
-
-    /* Now add in the days */
-
-    doy--;
-    tt += doy *60*60*24;
+    static const short days_in_year[2][13] = 
+    { /* jan feb mar apr may  jun  jul  aug  sep  oct  nov  dec */
+      {  0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, 
+      {  0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
+    };
+    struct icaltimetype tt = { 0 };
+    int is_leap = 0, month;
+
+    tt.year = year;
+    if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
+	is_leap = 1;
+
+    assert(doy > 0);
+    assert(doy <= days_in_year[is_leap][12]);
+
+    for (month = 11; month >= 0; month--) {
+      if (doy > days_in_year[is_leap][month]) {
+	tt.month = month + 1;
+	tt.day = doy - days_in_year[is_leap][month];
+	return tt;
+      }
+    }
 
-    return icaltime_from_timet(tt, 1);
+    /* Shouldn't reach here. */
+    assert (0);
 }
 
 struct icaltimetype icaltime_null_time()
@@ -564,3 +574,74 @@ struct icaldurationtype  icaltime_subtract(struct icaltimetype t1,
 
 
 
+/* Adds (or subtracts) a time from a icaltimetype.
+   NOTE: This function is exactly the same as icaltimezone_adjust_change()
+   except for the type of the first parameter. */
+void
+icaltime_adjust				(struct icaltimetype	*tt,
+					 int		 days,
+					 int		 hours,
+					 int		 minutes,
+					 int		 seconds)
+{
+    int second, minute, hour, day;
+    int minutes_overflow, hours_overflow, days_overflow;
+    int days_in_month;
+
+    /* Add on the seconds. */
+    second = tt->second + seconds;
+    tt->second = second % 60;
+    minutes_overflow = second / 60;
+    if (tt->second < 0) {
+	tt->second += 60;
+	minutes_overflow--;
+    }
+
+    /* Add on the minutes. */
+    minute = tt->minute + minutes + minutes_overflow;
+    tt->minute = minute % 60;
+    hours_overflow = minute / 60;
+    if (tt->minute < 0) {
+	tt->minute += 60;
+	hours_overflow--;
+    }
+
+    /* Add on the hours. */
+    hour = tt->hour + hours + hours_overflow;
+    tt->hour = hour % 24;
+    days_overflow = hour / 24;
+    if (tt->hour < 0) {
+	tt->hour += 24;
+	days_overflow--;
+    }
+
+    /* Add on the days. */
+    day = tt->day + days + days_overflow;
+    if (day > 0) {
+	for (;;) {
+	    days_in_month = icaltime_days_in_month (tt->month, tt->year);
+	    if (day <= days_in_month)
+		break;
+
+	    tt->month++;
+	    if (tt->month >= 13) {
+		tt->year++;
+		tt->month = 1;
+	    }
+
+	    day -= days_in_month;
+	}
+    } else {
+	while (day <= 0) {
+	    if (tt->month == 1) {
+		tt->year--;
+		tt->month = 12;
+	    } else {
+		tt->month--;
+	    }
+
+	    day += icaltime_days_in_month (tt->month, tt->year);
+	}
+    }
+    tt->day = day;
+}
diff --git a/libical/src/libical/icaltime.h b/libical/src/libical/icaltime.h
index 0f0379b76e..afe8fd4df2 100644
--- a/libical/src/libical/icaltime.h
+++ b/libical/src/libical/icaltime.h
@@ -41,8 +41,8 @@ struct icaltime_span {
 
 struct icaltimetype
 {
-	int year;
-	int month;
+	int year;	/* Actual year, e.g. 2001. */
+	int month;	/* 1 (Jan) to 12 (Dec). */
 	int day;
 	int hour;
 	int minute;
@@ -51,6 +51,8 @@ struct icaltimetype
 	int is_utc; /* 1-> time is in UTC timezone */
 
 	int is_date; /* 1 -> interpret this as date. */
+
+	int is_daylight; /* 1 -> time is in daylight savings time. */
    
 	const char* zone; /*Ptr to Olsen placename. Libical does not own mem*/
 };	
@@ -138,6 +140,9 @@ int icaltime_compare_date_only(struct icaltimetype a, struct icaltimetype b);
 /* Return the number of days in the given month */
 short icaltime_days_in_month(short month,short year);
 
+/* Adds or subtracts a number of days, hours, minutes and seconds. */
+void  icaltime_adjust(struct icaltimetype *tt, int days, int hours,
+		      int minutes, int seconds);
 
 #endif /* !ICALTIME_H */
 
diff --git a/libical/src/libical/icalyacc.y b/libical/src/libical/icalyacc.y
index 982682d331..c78299fa2a 100644
--- a/libical/src/libical/icalyacc.y
+++ b/libical/src/libical/icalyacc.y
@@ -6,7 +6,7 @@
   
   DESCRIPTION:
   
-  $Id: icalyacc.y,v 1.11 2001/01/23 20:22:33 jpr Exp $
+  $Id: icalyacc.y,v 1.12 2001/06/14 02:50:46 damon Exp $
   $Locker:  $
 
   (C) COPYRIGHT 1999 Eric Busboom 
@@ -367,12 +367,12 @@ plusminus: '+' { utcsign = 1; }
 utcoffset_value: 
 	plusminus INTNUMBER INTNUMBER
 	{
-	    icalparser_yy_value = icalvalue_new_utcoffset( utcsign * ($2*3600) + ($3*60) );
+	    icalparser_yy_value = icalvalue_new_utcoffset( utcsign * (($2*3600) + ($3*60)) );
   	}
 
 	| plusminus INTNUMBER INTNUMBER INTNUMBER
 	{
-	    icalparser_yy_value = icalvalue_new_utcoffset(utcsign * ($2*3600) + ($3*60) +($4));
+	    icalparser_yy_value = icalvalue_new_utcoffset(utcsign * (($2*3600) + ($3*60) +($4)));
   	}
 
 %%