Function afterTriggerRestoreEventList

src/backend/commands/trigger.c:3891–3921

---------- * afterTriggerRestoreEventList() * * Restore an event list to its prior length, removing all the events * added since it had the value old_events. * ---------- */

 * ----------
 */
static void
afterTriggerRestoreEventList(AfterTriggerEventList *events,
							 const AfterTriggerEventList *old_events)
{
	AfterTriggerEventChunk *chunk;
	AfterTriggerEventChunk *next_chunk;

	if (old_events->tail == NULL)
	{
		/* restoring to a completely empty state, so free everything */
		afterTriggerFreeEventList(events);
	}
	else
	{
		*events = *old_events;
		/* free any chunks after the last one we want to keep */
		for (chunk = events->tail->next; chunk != NULL; chunk = next_chunk)
		{
			next_chunk = chunk->next;
			pfree(chunk);
		}
		/* and clean up the tail chunk to be the right length */
		events->tail->next = NULL;
		events->tail->freeptr = events->tailfree;

		/*
		 * We don't make any effort to remove now-unused shared data records.
		 * They might still be useful, anyway.
		 */
	}
}

/* ----------
 * afterTriggerDeleteHeadEventChunk()