Function

ECalClientcheck_timezones_sync

since: 3.34

Declaration [src]

gboolean
e_cal_client_check_timezones_sync (
  ICalComponent* vcalendar,
  GSList* icalcomps,
  ECalRecurResolveTimezoneCb tzlookup,
  gpointer tzlookup_data,
  GCancellable* cancellable,
  GError** error
)

Description [src]

This function cleans up VEVENT, VJOURNAL, VTODO and VTIMEZONE items which are to be imported into Evolution.

Using VTIMEZONE definitions is problematic because they cannot be updated properly when timezone definitions change. They are also incomplete (for compatibility reason only one set of rules for summer saving changes can be included, even if different rules apply in different years). This function looks for matches of the used TZIDs against system timezones and replaces such TZIDs with the corresponding system timezone. This works for TZIDs containing a location (found via a fuzzy string search) and for Outlook TZIDs (via a hard-coded lookup table).

Some programs generate broken meeting invitations with TZID, but without including the corresponding VTIMEZONE. Importing such invitations unchanged causes problems later on (meeting displayed incorrectly, e_cal_component_get_as_string() fails). The situation where this occurred in the past (found by a SyncEvolution user) is now handled via the location based mapping.

If this mapping fails, this function also deals with VTIMEZONE conflicts: such conflicts occur when the calendar already contains an old VTIMEZONE definition with the same TZID, but different summer saving rules. Replacing the VTIMEZONE potentially breaks displaying of old events, whereas not replacing it breaks the new events (the behavior in Evolution <= 2.22.1).

The way this problem is resolved by renaming the new VTIMEZONE definition until the TZID is unique. A running count is appended to the TZID. All items referencing the renamed TZID are adapted accordingly.

Available since: 3.34

Parameters

vcalendar

Type: None

A VCALENDAR containing a list of VTIMEZONE and arbitrary other components, in arbitrary order: these other components are modified by this call.

The data is owned by the caller of the function.
icalcomps

Type: A list of ICalComponent*

A list of ICalComponent instances which also have to be patched; may be NULL.

The argument can be NULL.
The data is owned by the caller of the function.
tzlookup

Type: ECalRecurResolveTimezoneCb

A callback function which is called to retrieve a calendar’s VTIMEZONE definition; the returned definition is not freed by e_cal_client_check_timezones() NULL indicates that no such timezone exists or an error occurred.

tzlookup_data

Type: gpointer

An arbitrary pointer which is passed through to the tzlookup function.

The argument can be NULL.
The data is owned by the caller of the function.
cancellable

Type: GCancellable

A GCancellable to use in tzlookup function.

The argument can be NULL.
The data is owned by the caller of the function.
error

Type: GError **

The return location for a recoverable error.

The argument can be NULL.
If the return location is not NULL, then you must initialize it to a NULL GError*.
The argument will be left initialized to NULL by the function if there are no errors.
In case of error, the argument will be set to a newly allocated GError; the caller will take ownership of the data, and be responsible for freeing it.

Return value

Type: gboolean

TRUE if successful, FALSE otherwise.