In order to keep processing times from getting out of hand for huge (or bad) input data libical enforces these internal limits. However, these limits can be changed at runtime using the icallimit_set() function. Similarly, the limits can be queried using icallimit_get().

The internal limits and their default values are shown here:

Maximum number of parse failures allowed in a calendar file before processing halts
```
Kind = ICAL_LIMIT_PARSE_FAILURES
Default = 1000 (one thousand)
```

Maximum number of parse characters to search in a calendar component for the next parameter or property
```
Kind = ICAL_LIMIT_PARSE_SEARCH
Default = 100000 (one hundred thousand)
```

Maximum number of parse failure messages inserted into the output (by insert_error())
```
Kind = ICAL_LIMIT_PARSE_FAILURE_ERROR_MESSAGES
Default = 100 (one hundred)
```

Maximum number of properties allowed in a calendar component

Kind = ICAL_LIMIT_PROPERTIES
Default = 10000 (ten thousand)

Maximum number of parameters allowed for a property

Kind = ICAL_LIMIT_PARAMETERS
Default = 100 (one hundred)

Maximum number of characters for a value

Kind = ICAL_LIMIT_VALUE_CHARS
Default = 10485760 (10 * 1024 * 1024 ie. 10 mega chars)

Maximum number of values allowed for multi-valued properties
```
Kind = ICAL_LIMIT_PROPERTY_VALUES
Default = 500
```

Maximum number of times to search for the next recurrence before giving up

Kind = ICAL_LIMIT_RECURRENCE_SEARCH
Default = 100000 (one hundred thousand)

Maximum number of times to search for the next recurrence before time is considered standing still
```
Kind = ICAL_LIMIT_RECURRENCE_TIME_STANDING_STILL
Default = 50 (fifty)
```

Maximum number of times to search vtimezone rrules for an occurrence before the specified end year
```
Kind = ICAL_LIMIT_RRULE_SEARCH
Default = 100 (one hundred)
```