Tom Lane wrote:
What cases have you gotten to work correctly?
My guess is that you're either messed up about V0 vs V1 calling
convention (ie you forgot PG_FUNCTION_INFO_V1, or added it when you
shouldn't have), or you've got some kind of problem with not detoasting
toasted input values. There's not enough info here to venture more.
regards, tom lane
This one works correctly:
PG_FUNCTION_INFO_V1(event_duration);
Datum
event_duration(PG_FUNCTION_ARGS)
{
int32 state = PG_GETARG_INT32(0);
int32 target = PG_GETARG_INT32(1);
int32 event = PG_GETARG_INT32(2);
Timestamp start = PG_GETARG_TIMESTAMP(3);
Timestamp end = PG_GETARG_TIMESTAMP(4);
//If this event is the correct type we need to add the event time
to the total event time (state)
if(target == event){
state += (end - start);
}
PG_RETURN_INT32(state);
}
I can use event_duration in this query without problems:
SELECT call_id, event_duration(4,event_type,start_time,end_time) AS
talking_duration FROM event GROUP BY call_id;
One case that fails is essentially copied from the V1 section in the
documentation:
PG_FUNCTION_INFO_V1(copytext);
Datum copytext(PG_FUNCTION_ARGS)
{
text* t = PG_GETARG_TEXT_P(0);
text* new_t = (text *) palloc(VARSIZE(t));
SET_VARSIZE(new_t, VARSIZE(t));
memcpy((void *) VARDATA(new_t), (void *) VARDATA(t),
VARSIZE(t) - VARHDRSZ);
PG_RETURN_TEXT_P(new_t);
}
Attempting to use copytext in a query results in Postgres crashing.
For example:
SELECT copytext(calling_party) FROM event;
crashes.
- Dan
