/*
* Pre-commit processing for portals.
*
* Any holdable cursors created in this transaction need to be converted to
* materialized form, since we are going to close down the executor and
* release locks. Other portals are not touched yet.
*
* Returns TRUE if any holdable cursors were processed, FALSE if not.
*/
bool
CommitHoldablePortals(void)
{
bool result = false;
HASH_SEQ_STATUS status;
PortalHashEnt *hentry;
hash_seq_init(&status, PortalHashTable);
while ((hentry = (PortalHashEnt *) hash_seq_search(&status)) != NULL)
{
Portal portal = hentry->portal;
/* Is it a holdable portal created in the current xact? */
if ((portal->cursorOptions & CURSOR_OPT_HOLD) &&
portal->createSubid != InvalidSubTransactionId &&
portal->status == PORTAL_READY)
{
/*
* We are exiting the transaction that created a holdable
* cursor. Instead of dropping the portal, prepare it for
* access by later transactions.
*
* Note that PersistHoldablePortal() must release all resources
* used by the portal that are local to the creating
* transaction.
*/
PortalCreateHoldStore(portal);
PersistHoldablePortal(portal);
/*
* Any resources belonging to the portal will be released in
* the upcoming transaction-wide cleanup; the portal will no
* longer have its own resources.
*/
portal->resowner = NULL;
/*
* Having successfully exported the holdable cursor, mark it
* as not belonging to this transaction.
*/
portal->createSubid = InvalidSubTransactionId;
result = true;
}
}
return result;
}
/*
* Pre-commit processing for portals.
*
* Any holdable cursors created in this transaction need to be converted to
* materialized form, since we are going to close down the executor and
* release locks. Remove all other portals created in this transaction.
* Portals remaining from prior transactions should be left untouched.
*
* XXX This assumes that portals can be deleted in a random order, ie,
* no portal has a reference to any other (at least not one that will be
* exercised during deletion). I think this is okay at the moment, but
* we've had bugs of that ilk in the past. Keep a close eye on cursor
* references...
*/
void
AtCommit_Portals(void)
{
HASH_SEQ_STATUS status;
PortalHashEnt *hentry;
TransactionId xact = GetCurrentTransactionId();
hash_seq_init(&status, PortalHashTable);
while ((hentry = (PortalHashEnt *) hash_seq_search(&status)) != NULL)
{
Portal portal = hentry->portal;
/*
* Do not touch active portals --- this can only happen in the
* case of a multi-transaction utility command, such as VACUUM.
*/
if (portal->portalActive)
continue;
if (portal->cursorOptions & CURSOR_OPT_HOLD)
{
/*
* Do nothing to cursors held over from a previous
* transaction.
*/
if (portal->createXact != xact)
continue;
/*
* We are exiting the transaction that created a holdable
* cursor. Instead of dropping the portal, prepare it for
* access by later transactions.
*
* Note that PersistHoldablePortal() must release all resources
* used by the portal that are local to the creating
* transaction.
*/
PortalCreateHoldStore(portal);
PersistHoldablePortal(portal);
}
else
{
/* Zap all non-holdable portals */
PortalDrop(portal, false);
}
}
}
