1 // Go through an ical component set and convert all non-UTC date/time properties to UTC.
2 // It also strips out any VTIMEZONE subcomponents afterwards, because they are now unreferenced.
4 // Everything here will work on both components and subcomponents. If subcomponents are discovered it will recurse through them.
6 // Copyright (c) 2002-2024 by the citadel.org team (Art Cancro et al)
7 // This program is open source software. Use, duplication, or disclosure is subject to the GNU General Public License v3.
9 // NOTE: this file is symlinked between different generations of WebCit. When we retire WebCit-classic, copy the file over.
14 // Figure out which time zone needs to be used for timestamps that are not UTC and do not have a time zone specified.
15 icaltimezone *get_default_icaltimezone(void) {
17 icaltimezone *zone = NULL;
20 zone = icaltimezone_get_builtin_timezone(default_zone_name);
23 syslog(LOG_WARNING, "ical_dezonify: unable to load '%s' time zone, defaulting to UTC", default_zone_name);
24 zone = icaltimezone_get_utc_timezone();
27 syslog(LOG_ERR, "ical_dezonify: unable to load UTC time zone!");
33 // Back end function for ical_dezonify()
35 // We supply this with the master component, the relevant component, and the property
36 // (which will be a DTSTART, DTEND, etc.) which we want to convert to UTC.
37 void ical_dezonify_backend(icalcomponent *cal, icalcomponent *rcal, icalproperty *prop) {
39 icaltimezone *t = NULL;
41 const char *tzid = NULL;
42 struct icaltimetype TheTime;
43 int utc_declared_as_tzid = 0; // Component declared 'TZID=GMT' instead of using Z syntax
45 // Give me nothing and I will give you nothing in return.
46 if (cal == NULL) return;
48 // Hunt for a TZID parameter in this property.
49 param = icalproperty_get_first_parameter(prop, ICAL_TZID_PARAMETER);
51 // Get the stringish name of this TZID.
53 tzid = icalparameter_get_tzid(param);
55 // Convert it to an icaltimezone type.
58 syslog(LOG_DEBUG, "ical_dezonify: Stringy supplied timezone is: '%s'\n", tzid);
60 if ( (!strcasecmp(tzid, "UTC")) || (!strcasecmp(tzid, "GMT")) ) {
61 utc_declared_as_tzid = 1;
63 syslog(LOG_DEBUG, "ical_dezonify: ...and we handle that internally.\n");
68 t = icalcomponent_get_timezone(cal, tzid);
70 syslog(LOG_DEBUG, "ical_dezonify: ...and I %s have tzdata for that zone.\n",
74 // then try built-in timezones
76 t = icaltimezone_get_builtin_timezone(tzid);
79 syslog(LOG_DEBUG, "ical_dezonify: Using system tzdata!\n");
88 // Now we know the timezone. Convert to UTC.
90 if (icalproperty_isa(prop) == ICAL_DTSTART_PROPERTY) {
91 TheTime = icalproperty_get_dtstart(prop);
93 else if (icalproperty_isa(prop) == ICAL_DTEND_PROPERTY) {
94 TheTime = icalproperty_get_dtend(prop);
96 else if (icalproperty_isa(prop) == ICAL_DUE_PROPERTY) {
97 TheTime = icalproperty_get_due(prop);
99 else if (icalproperty_isa(prop) == ICAL_EXDATE_PROPERTY) {
100 TheTime = icalproperty_get_exdate(prop);
107 syslog(LOG_DEBUG, "ical_dezonify: was: %s\n", icaltime_as_ical_string(TheTime));
110 if (icaltime_is_utc(TheTime)) {
112 syslog(LOG_DEBUG, "ical_dezonify: this property is ALREADY UTC");
116 else if (utc_declared_as_tzid) {
118 syslog(LOG_DEBUG, "ical_dezonify: replacing '%s' TZID with 'Z' suffix", tzid);
120 TheTime.zone = icaltimezone_get_utc_timezone();
124 // Do the conversion.
127 syslog(LOG_DEBUG, "ical_dezonify: timezone prop found, converting to UTC");
132 syslog(LOG_DEBUG, "ical_dezonify: converting default timezone to UTC");
137 t = get_default_icaltimezone();
139 icaltimezone_convert_time(&TheTime, t, icaltimezone_get_utc_timezone());
140 TheTime.zone = icaltimezone_get_utc_timezone();
143 icalproperty_remove_parameter_by_kind(prop, ICAL_TZID_PARAMETER);
145 syslog(LOG_DEBUG, "ical_dezonify: now: %s", icaltime_as_ical_string(TheTime));
148 // Now add the converted property back in.
149 if (icalproperty_isa(prop) == ICAL_DTSTART_PROPERTY) {
150 icalproperty_set_dtstart(prop, TheTime);
152 else if (icalproperty_isa(prop) == ICAL_DTEND_PROPERTY) {
153 icalproperty_set_dtend(prop, TheTime);
155 else if (icalproperty_isa(prop) == ICAL_DUE_PROPERTY) {
156 icalproperty_set_due(prop, TheTime);
158 else if (icalproperty_isa(prop) == ICAL_EXDATE_PROPERTY) {
159 icalproperty_set_exdate(prop, TheTime);
164 // Recursive portion of ical_dezonify()
165 void ical_dezonify_recurse(icalcomponent *cal, icalcomponent *rcal) {
169 // Recurse through all subcomponents *except* VTIMEZONE ones.
170 for ( c=icalcomponent_get_first_component(rcal, ICAL_ANY_COMPONENT);
172 c = icalcomponent_get_next_component(rcal, ICAL_ANY_COMPONENT)
174 if (icalcomponent_isa(c) != ICAL_VTIMEZONE_COMPONENT) {
175 ical_dezonify_recurse(cal, c);
179 // Now look for DTSTART and DTEND properties
180 for ( p=icalcomponent_get_first_property(rcal, ICAL_ANY_PROPERTY);
182 p = icalcomponent_get_next_property(rcal, ICAL_ANY_PROPERTY)
185 (icalproperty_isa(p) == ICAL_DTSTART_PROPERTY)
186 || (icalproperty_isa(p) == ICAL_DTEND_PROPERTY)
187 || (icalproperty_isa(p) == ICAL_DUE_PROPERTY)
188 || (icalproperty_isa(p) == ICAL_EXDATE_PROPERTY)
190 ical_dezonify_backend(cal, rcal, p);
196 // Convert all DTSTART and DTEND properties in all subcomponents to UTC.
197 // This function will search any VTIMEZONE subcomponents to learn the
198 // relevant timezone information.
199 void ical_dezonify(icalcomponent *cal) {
200 icalcomponent *vt = NULL;
203 syslog(LOG_DEBUG, "ical_dezonify() started");
206 // Convert all times to UTC
207 ical_dezonify_recurse(cal, cal);
209 // Strip out VTIMEZONE subcomponents -- we don't need them anymore.
210 while (vt = icalcomponent_get_first_component(cal, ICAL_VTIMEZONE_COMPONENT), vt != NULL) {
211 icalcomponent_remove_component(cal, vt);
212 icalcomponent_free(vt);
216 syslog(LOG_DEBUG, "ical_dezonify() completed");