Exemplo n.º 1
0
/*
 * Decide whether a cached PLyProcedure struct is still valid
 */
static bool
PLy_procedure_valid(PLyProcedure *proc, HeapTuple procTup)
{
	int			i;
	bool		valid;

	Assert(proc != NULL);

	/* If the pg_proc tuple has changed, it's not valid */
	if (!(proc->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
		  ItemPointerEquals(&proc->fn_tid, &procTup->t_self)))
		return false;

	/* Else check the input argument datatypes */
	valid = true;
	for (i = 0; i < proc->nargs; i++)
	{
		valid = PLy_procedure_argument_valid(&proc->args[i]);

		/* Short-circuit on first changed argument */
		if (!valid)
			break;
	}

	/* if the output type is composite, it might have changed */
	if (valid)
		valid = PLy_procedure_argument_valid(&proc->result);

	return valid;
}
Exemplo n.º 2
0
/*
 * Check if our cached information about a datatype is still valid
 */
static bool
PLy_procedure_argument_valid(PLyTypeInfo *arg)
{
	HeapTuple	relTup;
	bool		valid;

	/* Nothing to cache unless type is composite */
	if (arg->is_rowtype != 1)
		return true;

	/*
	 * Zero typ_relid means that we got called on an output argument of a
	 * function returning a unnamed record type; the info for it can't change.
	 */
	if (!OidIsValid(arg->typ_relid))
		return true;

	/* Else we should have some cached data */
	Assert(TransactionIdIsValid(arg->typrel_xmin));
	Assert(ItemPointerIsValid(&arg->typrel_tid));

	/* Get the pg_class tuple for the data type */
	relTup = SearchSysCache1(RELOID, ObjectIdGetDatum(arg->typ_relid));
	if (!HeapTupleIsValid(relTup))
		elog(ERROR, "cache lookup failed for relation %u", arg->typ_relid);

	/* If it has changed, the cached data is not valid */
	valid = (arg->typrel_xmin == HeapTupleHeaderGetRawXmin(relTup->t_data) &&
			 ItemPointerEquals(&arg->typrel_tid, &relTup->t_self));

	ReleaseSysCache(relTup);

	return valid;
}
Exemplo n.º 3
0
/*
 * Decide whether a cached PLyProcedure struct is still valid
 */
static bool
PLy_procedure_valid(PLyProcedure *proc, HeapTuple procTup)
{
	if (proc == NULL)
		return false;

	/* If the pg_proc tuple has changed, it's not valid */
	if (!(proc->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
		  ItemPointerEquals(&proc->fn_tid, &procTup->t_self)))
		return false;

	return true;
}
Exemplo n.º 4
0
/*
 * Given a tuple we are about to delete, determine the correct value to store
 * into its t_cid field.
 *
 * If we don't need a combo CID, *cmax is unchanged and *iscombo is set to
 * FALSE.  If we do need one, *cmax is replaced by a combo CID and *iscombo
 * is set to TRUE.
 *
 * The reason this is separate from the actual HeapTupleHeaderSetCmax()
 * operation is that this could fail due to out-of-memory conditions.  Hence
 * we need to do this before entering the critical section that actually
 * changes the tuple in shared buffers.
 */
void
HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
						  CommandId *cmax,
						  bool *iscombo)
{
	/*
	 * If we're marking a tuple deleted that was inserted by (any
	 * subtransaction of) our transaction, we need to use a combo command id.
	 * Test for HeapTupleHeaderXminCommitted() first, because it's cheaper than a
	 * TransactionIdIsCurrentTransactionId call.
	 */
	if (!HeapTupleHeaderXminCommitted(tup) &&
		TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tup)))
	{
		CommandId	cmin = HeapTupleHeaderGetCmin(tup);

		*cmax = GetComboCommandId(cmin, *cmax);
		*iscombo = true;
	}
	else
	{
		*iscombo = false;
	}
}
Exemplo n.º 5
0
/*
 * HeapTupleSatisfiesMVCC
 *		True iff heap tuple is valid for the given MVCC snapshot.
 *
 *	Here, we consider the effects of:
 *		all transactions committed as of the time of the given snapshot
 *		previous commands of this transaction
 *
 *	Does _not_ include:
 *		transactions shown as in-progress by the snapshot
 *		transactions started after the snapshot was taken
 *		changes made by the current command
 *
 * (Notice, however, that the tuple status hint bits will be updated on the
 * basis of the true state of the transaction, even if we then pretend we
 * can't see it.)
 */
bool
HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
					   Buffer buffer)
{
	HeapTupleHeader tuple = htup->t_data;

	Assert(ItemPointerIsValid(&htup->t_self));
	Assert(htup->t_tableOid != InvalidOid);

	if (!HeapTupleHeaderXminCommitted(tuple))
	{
		if (HeapTupleHeaderXminInvalid(tuple))
			return false;

		/* Used by pre-9.0 binary upgrades */
		if (tuple->t_infomask & HEAP_MOVED_OFF)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (TransactionIdIsCurrentTransactionId(xvac))
				return false;
			if (!TransactionIdIsInProgress(xvac))
			{
				if (TransactionIdDidCommit(xvac))
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return false;
				}
				SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
							InvalidTransactionId);
			}
		}
		/* Used by pre-9.0 binary upgrades */
		else if (tuple->t_infomask & HEAP_MOVED_IN)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (!TransactionIdIsCurrentTransactionId(xvac))
			{
				if (TransactionIdIsInProgress(xvac))
					return false;
				if (TransactionIdDidCommit(xvac))
					SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
								InvalidTransactionId);
				else
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return false;
				}
			}
		}
		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
		{
			if (HeapTupleHeaderGetCmin(tuple) >= snapshot->curcid)
				return false;	/* inserted after scan started */

			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
				return true;

			if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))	/* not deleter */
				return true;

			if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
			{
				TransactionId xmax;

				xmax = HeapTupleGetUpdateXid(tuple);

				/* not LOCKED_ONLY, so it has to have an xmax */
				Assert(TransactionIdIsValid(xmax));

				/* updating subtransaction must have aborted */
				if (!TransactionIdIsCurrentTransactionId(xmax))
					return true;
				else if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
					return true;	/* updated after scan started */
				else
					return false;		/* updated before scan started */
			}

			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
			{
				/* deleting subtransaction must have aborted */
				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
							InvalidTransactionId);
				return true;
			}

			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
				return true;	/* deleted after scan started */
			else
				return false;	/* deleted before scan started */
		}
		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
			return false;
		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
						HeapTupleHeaderGetRawXmin(tuple));
		else
		{
			/* it must have aborted or crashed */
			SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
						InvalidTransactionId);
			return false;
		}
	}

	/*
	 * By here, the inserting transaction has committed - have to check
	 * when...
	 */
	if (!HeapTupleHeaderXminFrozen(tuple)
		&& XidInMVCCSnapshot(HeapTupleHeaderGetRawXmin(tuple), snapshot))
		return false;			/* treat as still in progress */

	if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid or aborted */
		return true;

	if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
		return true;

	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
	{
		TransactionId xmax;

		/* already checked above */
		Assert(!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask));

		xmax = HeapTupleGetUpdateXid(tuple);

		/* not LOCKED_ONLY, so it has to have an xmax */
		Assert(TransactionIdIsValid(xmax));

		if (TransactionIdIsCurrentTransactionId(xmax))
		{
			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
				return true;	/* deleted after scan started */
			else
				return false;	/* deleted before scan started */
		}
		if (TransactionIdIsInProgress(xmax))
			return true;
		if (TransactionIdDidCommit(xmax))
		{
			/* updating transaction committed, but when? */
			if (XidInMVCCSnapshot(xmax, snapshot))
				return true;	/* treat as still in progress */
			return false;
		}
		/* it must have aborted or crashed */
		return true;
	}

	if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
	{
		if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
		{
			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
				return true;	/* deleted after scan started */
			else
				return false;	/* deleted before scan started */
		}

		if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
			return true;

		if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
		{
			/* it must have aborted or crashed */
			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
						InvalidTransactionId);
			return true;
		}

		/* xmax transaction committed */
		SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
					HeapTupleHeaderGetRawXmax(tuple));
	}

	/*
	 * OK, the deleting transaction committed too ... but when?
	 */
	if (XidInMVCCSnapshot(HeapTupleHeaderGetRawXmax(tuple), snapshot))
		return true;			/* treat as still in progress */

	return false;
}
Exemplo n.º 6
0
/*
 * HeapTupleSatisfiesDirty
 *		True iff heap tuple is valid including effects of open transactions.
 *
 *	Here, we consider the effects of:
 *		all committed and in-progress transactions (as of the current instant)
 *		previous commands of this transaction
 *		changes made by the current command
 *
 * This is essentially like HeapTupleSatisfiesSelf as far as effects of
 * the current transaction and committed/aborted xacts are concerned.
 * However, we also include the effects of other xacts still in progress.
 *
 * A special hack is that the passed-in snapshot struct is used as an
 * output argument to return the xids of concurrent xacts that affected the
 * tuple.  snapshot->xmin is set to the tuple's xmin if that is another
 * transaction that's still in progress; or to InvalidTransactionId if the
 * tuple's xmin is committed good, committed dead, or my own xact.  Similarly
 * for snapshot->xmax and the tuple's xmax.
 */
bool
HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
						Buffer buffer)
{
	HeapTupleHeader tuple = htup->t_data;

	Assert(ItemPointerIsValid(&htup->t_self));
	Assert(htup->t_tableOid != InvalidOid);

	snapshot->xmin = snapshot->xmax = InvalidTransactionId;

	if (!HeapTupleHeaderXminCommitted(tuple))
	{
		if (HeapTupleHeaderXminInvalid(tuple))
			return false;

		/* Used by pre-9.0 binary upgrades */
		if (tuple->t_infomask & HEAP_MOVED_OFF)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (TransactionIdIsCurrentTransactionId(xvac))
				return false;
			if (!TransactionIdIsInProgress(xvac))
			{
				if (TransactionIdDidCommit(xvac))
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return false;
				}
				SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
							InvalidTransactionId);
			}
		}
		/* Used by pre-9.0 binary upgrades */
		else if (tuple->t_infomask & HEAP_MOVED_IN)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (!TransactionIdIsCurrentTransactionId(xvac))
			{
				if (TransactionIdIsInProgress(xvac))
					return false;
				if (TransactionIdDidCommit(xvac))
					SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
								InvalidTransactionId);
				else
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return false;
				}
			}
		}
		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
		{
			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
				return true;

			if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))	/* not deleter */
				return true;

			if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
			{
				TransactionId xmax;

				xmax = HeapTupleGetUpdateXid(tuple);

				/* not LOCKED_ONLY, so it has to have an xmax */
				Assert(TransactionIdIsValid(xmax));

				/* updating subtransaction must have aborted */
				if (!TransactionIdIsCurrentTransactionId(xmax))
					return true;
				else
					return false;
			}

			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
			{
				/* deleting subtransaction must have aborted */
				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
							InvalidTransactionId);
				return true;
			}

			return false;
		}
		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
		{
			snapshot->xmin = HeapTupleHeaderGetRawXmin(tuple);
			/* XXX shouldn't we fall through to look at xmax? */
			return true;		/* in insertion by other */
		}
		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
						HeapTupleHeaderGetRawXmin(tuple));
		else
		{
			/* it must have aborted or crashed */
			SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
						InvalidTransactionId);
			return false;
		}
	}

	/* by here, the inserting transaction has committed */

	if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid or aborted */
		return true;

	if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
	{
		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			return true;
		return false;			/* updated by other */
	}

	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
	{
		TransactionId xmax;

		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			return true;

		xmax = HeapTupleGetUpdateXid(tuple);

		/* not LOCKED_ONLY, so it has to have an xmax */
		Assert(TransactionIdIsValid(xmax));

		if (TransactionIdIsCurrentTransactionId(xmax))
			return false;
		if (TransactionIdIsInProgress(xmax))
		{
			snapshot->xmax = xmax;
			return true;
		}
		if (TransactionIdDidCommit(xmax))
			return false;
		/* it must have aborted or crashed */
		return true;
	}

	if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
	{
		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			return true;
		return false;
	}

	if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
	{
		if (!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			snapshot->xmax = HeapTupleHeaderGetRawXmax(tuple);
		return true;
	}

	if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
	{
		/* it must have aborted or crashed */
		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
					InvalidTransactionId);
		return true;
	}

	/* xmax transaction committed */

	if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
	{
		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
					InvalidTransactionId);
		return true;
	}

	SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
				HeapTupleHeaderGetRawXmax(tuple));
	return false;				/* updated by other */
}
Exemplo n.º 7
0
/*
 * HeapTupleSatisfiesUpdate
 *
 *	This function returns a more detailed result code than most of the
 *	functions in this file, since UPDATE needs to know more than "is it
 *	visible?".  It also allows for user-supplied CommandId rather than
 *	relying on CurrentCommandId.
 *
 *	The possible return codes are:
 *
 *	HeapTupleInvisible: the tuple didn't exist at all when the scan started,
 *	e.g. it was created by a later CommandId.
 *
 *	HeapTupleMayBeUpdated: The tuple is valid and visible, so it may be
 *	updated.
 *
 *	HeapTupleSelfUpdated: The tuple was updated by the current transaction,
 *	after the current scan started.
 *
 *	HeapTupleUpdated: The tuple was updated by a committed transaction.
 *
 *	HeapTupleBeingUpdated: The tuple is being updated by an in-progress
 *	transaction other than the current transaction.  (Note: this includes
 *	the case where the tuple is share-locked by a MultiXact, even if the
 *	MultiXact includes the current transaction.  Callers that want to
 *	distinguish that case must test for it themselves.)
 */
HTSU_Result
HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
						 Buffer buffer)
{
	HeapTupleHeader tuple = htup->t_data;

	Assert(ItemPointerIsValid(&htup->t_self));
	Assert(htup->t_tableOid != InvalidOid);

	if (!HeapTupleHeaderXminCommitted(tuple))
	{
		if (HeapTupleHeaderXminInvalid(tuple))
			return HeapTupleInvisible;

		/* Used by pre-9.0 binary upgrades */
		if (tuple->t_infomask & HEAP_MOVED_OFF)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (TransactionIdIsCurrentTransactionId(xvac))
				return HeapTupleInvisible;
			if (!TransactionIdIsInProgress(xvac))
			{
				if (TransactionIdDidCommit(xvac))
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return HeapTupleInvisible;
				}
				SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
							InvalidTransactionId);
			}
		}
		/* Used by pre-9.0 binary upgrades */
		else if (tuple->t_infomask & HEAP_MOVED_IN)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (!TransactionIdIsCurrentTransactionId(xvac))
			{
				if (TransactionIdIsInProgress(xvac))
					return HeapTupleInvisible;
				if (TransactionIdDidCommit(xvac))
					SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
								InvalidTransactionId);
				else
				{
					SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
								InvalidTransactionId);
					return HeapTupleInvisible;
				}
			}
		}
		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
		{
			if (HeapTupleHeaderGetCmin(tuple) >= curcid)
				return HeapTupleInvisible;		/* inserted after scan started */

			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
				return HeapTupleMayBeUpdated;

			if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			{
				TransactionId xmax;

				xmax = HeapTupleHeaderGetRawXmax(tuple);

				/*
				 * Careful here: even though this tuple was created by our own
				 * transaction, it might be locked by other transactions, if
				 * the original version was key-share locked when we updated
				 * it.
				 */

				if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
				{
					if (MultiXactHasRunningRemoteMembers(xmax))
						return HeapTupleBeingUpdated;
					else
						return HeapTupleMayBeUpdated;
				}

				/* if locker is gone, all's well */
				if (!TransactionIdIsInProgress(xmax))
					return HeapTupleMayBeUpdated;

				if (!TransactionIdIsCurrentTransactionId(xmax))
					return HeapTupleBeingUpdated;
				else
					return HeapTupleMayBeUpdated;
			}

			if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
			{
				TransactionId xmax;

				xmax = HeapTupleGetUpdateXid(tuple);

				/* not LOCKED_ONLY, so it has to have an xmax */
				Assert(TransactionIdIsValid(xmax));

				/* updating subtransaction must have aborted */
				if (!TransactionIdIsCurrentTransactionId(xmax))
				{
					if (MultiXactHasRunningRemoteMembers(HeapTupleHeaderGetRawXmax(tuple)))
						return HeapTupleBeingUpdated;
					return HeapTupleMayBeUpdated;
				}
				else
				{
					if (HeapTupleHeaderGetCmax(tuple) >= curcid)
						return HeapTupleSelfUpdated;	/* updated after scan
														 * started */
					else
						return HeapTupleInvisible;		/* updated before scan
														 * started */
				}
			}

			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
			{
				/* deleting subtransaction must have aborted */
				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
							InvalidTransactionId);
				return HeapTupleMayBeUpdated;
			}

			if (HeapTupleHeaderGetCmax(tuple) >= curcid)
				return HeapTupleSelfUpdated;	/* updated after scan started */
			else
				return HeapTupleInvisible;		/* updated before scan started */
		}
		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
			return HeapTupleInvisible;
		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
						HeapTupleHeaderGetRawXmin(tuple));
		else
		{
			/* it must have aborted or crashed */
			SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
						InvalidTransactionId);
			return HeapTupleInvisible;
		}
	}

	/* by here, the inserting transaction has committed */

	if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid or aborted */
		return HeapTupleMayBeUpdated;

	if (tuple->t_infomask & HEAP_XMAX_COMMITTED)
	{
		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			return HeapTupleMayBeUpdated;
		return HeapTupleUpdated;	/* updated by other */
	}

	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
	{
		TransactionId xmax;

		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
		{
			/*
			 * If it's only locked but neither EXCL_LOCK nor KEYSHR_LOCK is
			 * set, it cannot possibly be running.  Otherwise need to check.
			 */
			if ((tuple->t_infomask & (HEAP_XMAX_EXCL_LOCK |
									  HEAP_XMAX_KEYSHR_LOCK)) &&
				MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple)))
				return HeapTupleBeingUpdated;

			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID, InvalidTransactionId);
			return HeapTupleMayBeUpdated;
		}

		xmax = HeapTupleGetUpdateXid(tuple);

		/* not LOCKED_ONLY, so it has to have an xmax */
		Assert(TransactionIdIsValid(xmax));

		if (TransactionIdIsCurrentTransactionId(xmax))
		{
			if (HeapTupleHeaderGetCmax(tuple) >= curcid)
				return HeapTupleSelfUpdated;	/* updated after scan started */
			else
				return HeapTupleInvisible;		/* updated before scan started */
		}

		if (TransactionIdIsInProgress(xmax))
			return HeapTupleBeingUpdated;

		if (TransactionIdDidCommit(xmax))
			return HeapTupleUpdated;

		/*
		 * By here, the update in the Xmax is either aborted or crashed, but
		 * what about the other members?
		 */

		if (!MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple)))
		{
			/*
			 * There's no member, even just a locker, alive anymore, so we can
			 * mark the Xmax as invalid.
			 */
			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
						InvalidTransactionId);
			return HeapTupleMayBeUpdated;
		}
		else
		{
			/* There are lockers running */
			return HeapTupleBeingUpdated;
		}
	}

	if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
	{
		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
			return HeapTupleMayBeUpdated;
		if (HeapTupleHeaderGetCmax(tuple) >= curcid)
			return HeapTupleSelfUpdated;		/* updated after scan started */
		else
			return HeapTupleInvisible;	/* updated before scan started */
	}

	if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
		return HeapTupleBeingUpdated;

	if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
	{
		/* it must have aborted or crashed */
		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
					InvalidTransactionId);
		return HeapTupleMayBeUpdated;
	}

	/* xmax transaction committed */

	if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
	{
		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
					InvalidTransactionId);
		return HeapTupleMayBeUpdated;
	}

	SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
				HeapTupleHeaderGetRawXmax(tuple));
	return HeapTupleUpdated;	/* updated by other */
}
Exemplo n.º 8
0
/*
 * HeapTupleSatisfiesVacuum
 *
 *	Determine the status of tuples for VACUUM purposes.  Here, what
 *	we mainly want to know is if a tuple is potentially visible to *any*
 *	running transaction.  If so, it can't be removed yet by VACUUM.
 *
 * OldestXmin is a cutoff XID (obtained from GetOldestXmin()).  Tuples
 * deleted by XIDs >= OldestXmin are deemed "recently dead"; they might
 * still be visible to some open transaction, so we can't remove them,
 * even if we see that the deleting transaction has committed.
 */
HTSV_Result
HeapTupleSatisfiesVacuum(HeapTuple htup, TransactionId OldestXmin,
						 Buffer buffer)
{
	HeapTupleHeader tuple = htup->t_data;

	Assert(ItemPointerIsValid(&htup->t_self));
	Assert(htup->t_tableOid != InvalidOid);

	/*
	 * Has inserting transaction committed?
	 *
	 * If the inserting transaction aborted, then the tuple was never visible
	 * to any other transaction, so we can delete it immediately.
	 */
	if (!HeapTupleHeaderXminCommitted(tuple))
	{
		if (HeapTupleHeaderXminInvalid(tuple))
			return HEAPTUPLE_DEAD;
		/* Used by pre-9.0 binary upgrades */
		else if (tuple->t_infomask & HEAP_MOVED_OFF)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (TransactionIdIsCurrentTransactionId(xvac))
				return HEAPTUPLE_DELETE_IN_PROGRESS;
			if (TransactionIdIsInProgress(xvac))
				return HEAPTUPLE_DELETE_IN_PROGRESS;
			if (TransactionIdDidCommit(xvac))
			{
				SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
							InvalidTransactionId);
				return HEAPTUPLE_DEAD;
			}
			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
						InvalidTransactionId);
		}
		/* Used by pre-9.0 binary upgrades */
		else if (tuple->t_infomask & HEAP_MOVED_IN)
		{
			TransactionId xvac = HeapTupleHeaderGetXvac(tuple);

			if (TransactionIdIsCurrentTransactionId(xvac))
				return HEAPTUPLE_INSERT_IN_PROGRESS;
			if (TransactionIdIsInProgress(xvac))
				return HEAPTUPLE_INSERT_IN_PROGRESS;
			if (TransactionIdDidCommit(xvac))
				SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
							InvalidTransactionId);
			else
			{
				SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
							InvalidTransactionId);
				return HEAPTUPLE_DEAD;
			}
		}
		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
		{
			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
				return HEAPTUPLE_INSERT_IN_PROGRESS;
			/* only locked? run infomask-only check first, for performance */
			if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask) ||
				HeapTupleHeaderIsOnlyLocked(tuple))
				return HEAPTUPLE_INSERT_IN_PROGRESS;
			/* inserted and then deleted by same xact */
			return HEAPTUPLE_DELETE_IN_PROGRESS;
		}
		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
						HeapTupleHeaderGetRawXmin(tuple));
		else
		{
			/*
			 * Not in Progress, Not Committed, so either Aborted or crashed
			 */
			SetHintBits(tuple, buffer, HEAP_XMIN_INVALID,
						InvalidTransactionId);
			return HEAPTUPLE_DEAD;
		}

		/*
		 * At this point the xmin is known committed, but we might not have
		 * been able to set the hint bit yet; so we can no longer Assert that
		 * it's set.
		 */
	}

	/*
	 * Okay, the inserter committed, so it was good at some point.  Now what
	 * about the deleting transaction?
	 */
	if (tuple->t_infomask & HEAP_XMAX_INVALID)
		return HEAPTUPLE_LIVE;

	if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
	{
		/*
		 * "Deleting" xact really only locked it, so the tuple is live in any
		 * case.  However, we should make sure that either XMAX_COMMITTED or
		 * XMAX_INVALID gets set once the xact is gone, to reduce the costs of
		 * examining the tuple for future xacts.  Also, marking dead
		 * MultiXacts as invalid here provides defense against MultiXactId
		 * wraparound (see also comments in heap_freeze_tuple()).
		 */
		if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
		{
			if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
			{
				/*
				 * If it's only locked but neither EXCL_LOCK nor KEYSHR_LOCK
				 * are set, it cannot possibly be running; otherwise have to
				 * check.
				 */
				if ((tuple->t_infomask & (HEAP_XMAX_EXCL_LOCK |
										  HEAP_XMAX_KEYSHR_LOCK)) &&
					MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple)))
					return HEAPTUPLE_LIVE;
				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID, InvalidTransactionId);

			}
			else
			{
				if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
					return HEAPTUPLE_LIVE;
				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
							InvalidTransactionId);
			}
		}

		/*
		 * We don't really care whether xmax did commit, abort or crash. We
		 * know that xmax did lock the tuple, but it did not and will never
		 * actually update it.
		 */

		return HEAPTUPLE_LIVE;
	}

	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
	{
		TransactionId xmax;

		if (MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple)))
		{
			/* already checked above */
			Assert(!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask));

			xmax = HeapTupleGetUpdateXid(tuple);

			/* not LOCKED_ONLY, so it has to have an xmax */
			Assert(TransactionIdIsValid(xmax));

			if (TransactionIdIsInProgress(xmax))
				return HEAPTUPLE_DELETE_IN_PROGRESS;
			else if (TransactionIdDidCommit(xmax))
				/* there are still lockers around -- can't return DEAD here */
				return HEAPTUPLE_RECENTLY_DEAD;
			/* updating transaction aborted */
			return HEAPTUPLE_LIVE;
		}

		Assert(!(tuple->t_infomask & HEAP_XMAX_COMMITTED));

		xmax = HeapTupleGetUpdateXid(tuple);

		/* not LOCKED_ONLY, so it has to have an xmax */
		Assert(TransactionIdIsValid(xmax));

		/* multi is not running -- updating xact cannot be */
		Assert(!TransactionIdIsInProgress(xmax));
		if (TransactionIdDidCommit(xmax))
		{
			if (!TransactionIdPrecedes(xmax, OldestXmin))
				return HEAPTUPLE_RECENTLY_DEAD;
			else
				return HEAPTUPLE_DEAD;
		}

		/*
		 * Not in Progress, Not Committed, so either Aborted or crashed.
		 * Remove the Xmax.
		 */
		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID, InvalidTransactionId);
		return HEAPTUPLE_LIVE;
	}

	if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
	{
		if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
			return HEAPTUPLE_DELETE_IN_PROGRESS;
		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
			SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
						HeapTupleHeaderGetRawXmax(tuple));
		else
		{
			/*
			 * Not in Progress, Not Committed, so either Aborted or crashed
			 */
			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
						InvalidTransactionId);
			return HEAPTUPLE_LIVE;
		}

		/*
		 * At this point the xmax is known committed, but we might not have
		 * been able to set the hint bit yet; so we can no longer Assert that
		 * it's set.
		 */
	}

	/*
	 * Deleter committed, but perhaps it was recent enough that some open
	 * transactions could still see the tuple.
	 */
	if (!TransactionIdPrecedes(HeapTupleHeaderGetRawXmax(tuple), OldestXmin))
		return HEAPTUPLE_RECENTLY_DEAD;

	/* Otherwise, it's dead and removable */
	return HEAPTUPLE_DEAD;
}
Exemplo n.º 9
0
/*
 * Create a new PLyProcedure structure
 */
static PLyProcedure *
PLy_procedure_create(HeapTuple procTup, Oid fn_oid, bool is_trigger)
{
	char		procName[NAMEDATALEN + 256];
	Form_pg_proc procStruct;
	PLyProcedure *volatile proc;
	char	   *volatile procSource = NULL;
	Datum		prosrcdatum;
	bool		isnull;
	int			i,
				rv;

	procStruct = (Form_pg_proc) GETSTRUCT(procTup);
	rv = snprintf(procName, sizeof(procName),
				  "__plpython_procedure_%s_%u",
				  NameStr(procStruct->proname),
				  fn_oid);
	if (rv >= sizeof(procName) || rv < 0)
		elog(ERROR, "procedure name would overrun buffer");

	proc = PLy_malloc(sizeof(PLyProcedure));
	proc->proname = PLy_strdup(NameStr(procStruct->proname));
	proc->pyname = PLy_strdup(procName);
	proc->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
	proc->fn_tid = procTup->t_self;
	/* Remember if function is STABLE/IMMUTABLE */
	proc->fn_readonly =
		(procStruct->provolatile != PROVOLATILE_VOLATILE);
	PLy_typeinfo_init(&proc->result);
	for (i = 0; i < FUNC_MAX_ARGS; i++)
		PLy_typeinfo_init(&proc->args[i]);
	proc->nargs = 0;
	proc->code = proc->statics = NULL;
	proc->globals = NULL;
	proc->is_setof = procStruct->proretset;
	proc->setof = NULL;
	proc->src = NULL;
	proc->argnames = NULL;

	PG_TRY();
	{
		/*
		 * get information required for output conversion of the return value,
		 * but only if this isn't a trigger.
		 */
		if (!is_trigger)
		{
			HeapTuple	rvTypeTup;
			Form_pg_type rvTypeStruct;

			rvTypeTup = SearchSysCache1(TYPEOID,
								   ObjectIdGetDatum(procStruct->prorettype));
			if (!HeapTupleIsValid(rvTypeTup))
				elog(ERROR, "cache lookup failed for type %u",
					 procStruct->prorettype);
			rvTypeStruct = (Form_pg_type) GETSTRUCT(rvTypeTup);

			/* Disallow pseudotype result, except for void or record */
			if (rvTypeStruct->typtype == TYPTYPE_PSEUDO)
			{
				if (procStruct->prorettype == TRIGGEROID)
					ereport(ERROR,
							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
							 errmsg("trigger functions can only be called as triggers")));
				else if (procStruct->prorettype != VOIDOID &&
						 procStruct->prorettype != RECORDOID)
					ereport(ERROR,
							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
						  errmsg("PL/Python functions cannot return type %s",
								 format_type_be(procStruct->prorettype))));
			}

			if (rvTypeStruct->typtype == TYPTYPE_COMPOSITE ||
				procStruct->prorettype == RECORDOID)
			{
				/*
				 * Tuple: set up later, during first call to
				 * PLy_function_handler
				 */
				proc->result.out.d.typoid = procStruct->prorettype;
				proc->result.out.d.typmod = -1;
				proc->result.is_rowtype = 2;
			}
			else
			{
				/* do the real work */
				PLy_output_datum_func(&proc->result, rvTypeTup);
			}

			ReleaseSysCache(rvTypeTup);
		}

		/*
		 * Now get information required for input conversion of the
		 * procedure's arguments.  Note that we ignore output arguments here.
		 * If the function returns record, those I/O functions will be set up
		 * when the function is first called.
		 */
		if (procStruct->pronargs)
		{
			Oid		   *types;
			char	  **names,
					   *modes;
			int			i,
						pos,
						total;

			/* extract argument type info from the pg_proc tuple */
			total = get_func_arg_info(procTup, &types, &names, &modes);

			/* count number of in+inout args into proc->nargs */
			if (modes == NULL)
				proc->nargs = total;
			else
			{
				/* proc->nargs was initialized to 0 above */
				for (i = 0; i < total; i++)
				{
					if (modes[i] != PROARGMODE_OUT &&
						modes[i] != PROARGMODE_TABLE)
						(proc->nargs)++;
				}
			}

			proc->argnames = (char **) PLy_malloc0(sizeof(char *) * proc->nargs);
			for (i = pos = 0; i < total; i++)
			{
				HeapTuple	argTypeTup;
				Form_pg_type argTypeStruct;

				if (modes &&
					(modes[i] == PROARGMODE_OUT ||
					 modes[i] == PROARGMODE_TABLE))
					continue;	/* skip OUT arguments */

				Assert(types[i] == procStruct->proargtypes.values[pos]);

				argTypeTup = SearchSysCache1(TYPEOID,
											 ObjectIdGetDatum(types[i]));
				if (!HeapTupleIsValid(argTypeTup))
					elog(ERROR, "cache lookup failed for type %u", types[i]);
				argTypeStruct = (Form_pg_type) GETSTRUCT(argTypeTup);

				/* check argument type is OK, set up I/O function info */
				switch (argTypeStruct->typtype)
				{
					case TYPTYPE_PSEUDO:
						/* Disallow pseudotype argument */
						ereport(ERROR,
								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
						  errmsg("PL/Python functions cannot accept type %s",
								 format_type_be(types[i]))));
						break;
					case TYPTYPE_COMPOSITE:
						/* we'll set IO funcs at first call */
						proc->args[pos].is_rowtype = 2;
						break;
					default:
						PLy_input_datum_func(&(proc->args[pos]),
											 types[i],
											 argTypeTup);
						break;
				}

				/* get argument name */
				proc->argnames[pos] = names ? PLy_strdup(names[i]) : NULL;

				ReleaseSysCache(argTypeTup);

				pos++;
			}
		}

		/*
		 * get the text of the function.
		 */
		prosrcdatum = SysCacheGetAttr(PROCOID, procTup,
									  Anum_pg_proc_prosrc, &isnull);
		if (isnull)
			elog(ERROR, "null prosrc");
		procSource = TextDatumGetCString(prosrcdatum);

		PLy_procedure_compile(proc, procSource);

		pfree(procSource);
		procSource = NULL;
	}
	PG_CATCH();
	{
		PLy_procedure_delete(proc);
		if (procSource)
			pfree(procSource);

		PG_RE_THROW();
	}
	PG_END_TRY();

	return proc;
}
Exemplo n.º 10
0
Datum
heap_page_items(PG_FUNCTION_ARGS)
{
	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
	heap_page_items_state *inter_call_data = NULL;
	FuncCallContext *fctx;
	int			raw_page_size;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use raw page functions"))));

	raw_page_size = VARSIZE(raw_page) - VARHDRSZ;

	if (SRF_IS_FIRSTCALL())
	{
		TupleDesc	tupdesc;
		MemoryContext mctx;

		if (raw_page_size < SizeOfPageHeaderData)
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
					 errmsg("input page too small (%d bytes)", raw_page_size)));

		fctx = SRF_FIRSTCALL_INIT();
		mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);

		inter_call_data = palloc(sizeof(heap_page_items_state));

		/* Build a tuple descriptor for our result type */
		if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
			elog(ERROR, "return type must be a row type");

		inter_call_data->tupd = tupdesc;

		inter_call_data->offset = FirstOffsetNumber;
		inter_call_data->page = VARDATA(raw_page);

		fctx->max_calls = PageGetMaxOffsetNumber(inter_call_data->page);
		fctx->user_fctx = inter_call_data;

		MemoryContextSwitchTo(mctx);
	}

	fctx = SRF_PERCALL_SETUP();
	inter_call_data = fctx->user_fctx;

	if (fctx->call_cntr < fctx->max_calls)
	{
		Page		page = inter_call_data->page;
		HeapTuple	resultTuple;
		Datum		result;
		ItemId		id;
		Datum		values[14];
		bool		nulls[14];
		uint16		lp_offset;
		uint16		lp_flags;
		uint16		lp_len;

		memset(nulls, 0, sizeof(nulls));

		/* Extract information from the line pointer */

		id = PageGetItemId(page, inter_call_data->offset);

		lp_offset = ItemIdGetOffset(id);
		lp_flags = ItemIdGetFlags(id);
		lp_len = ItemIdGetLength(id);

		values[0] = UInt16GetDatum(inter_call_data->offset);
		values[1] = UInt16GetDatum(lp_offset);
		values[2] = UInt16GetDatum(lp_flags);
		values[3] = UInt16GetDatum(lp_len);

		/*
		 * We do just enough validity checking to make sure we don't reference
		 * data outside the page passed to us. The page could be corrupt in
		 * many other ways, but at least we won't crash.
		 */
		if (ItemIdHasStorage(id) &&
			lp_len >= MinHeapTupleSize &&
			lp_offset == MAXALIGN(lp_offset) &&
			lp_offset + lp_len <= raw_page_size)
		{
			HeapTupleHeader tuphdr;
			bytea	   *tuple_data_bytea;
			int			tuple_data_len;

			/* Extract information from the tuple header */

			tuphdr = (HeapTupleHeader) PageGetItem(page, id);

			values[4] = UInt32GetDatum(HeapTupleHeaderGetRawXmin(tuphdr));
			values[5] = UInt32GetDatum(HeapTupleHeaderGetRawXmax(tuphdr));
			/* shared with xvac */
			values[6] = UInt32GetDatum(HeapTupleHeaderGetRawCommandId(tuphdr));
			values[7] = PointerGetDatum(&tuphdr->t_ctid);
			values[8] = UInt32GetDatum(tuphdr->t_infomask2);
			values[9] = UInt32GetDatum(tuphdr->t_infomask);
			values[10] = UInt8GetDatum(tuphdr->t_hoff);

			/* Copy raw tuple data into bytea attribute */
			tuple_data_len = lp_len - tuphdr->t_hoff;
			tuple_data_bytea = (bytea *) palloc(tuple_data_len + VARHDRSZ);
			SET_VARSIZE(tuple_data_bytea, tuple_data_len + VARHDRSZ);
			memcpy(VARDATA(tuple_data_bytea), (char *) tuphdr + tuphdr->t_hoff,
				   tuple_data_len);
			values[13] = PointerGetDatum(tuple_data_bytea);

			/*
			 * We already checked that the item is completely within the raw
			 * page passed to us, with the length given in the line pointer.
			 * Let's check that t_hoff doesn't point over lp_len, before using
			 * it to access t_bits and oid.
			 */
			if (tuphdr->t_hoff >= SizeofHeapTupleHeader &&
				tuphdr->t_hoff <= lp_len &&
				tuphdr->t_hoff == MAXALIGN(tuphdr->t_hoff))
			{
				if (tuphdr->t_infomask & HEAP_HASNULL)
				{
					int			bits_len;

					bits_len =
						BITMAPLEN(HeapTupleHeaderGetNatts(tuphdr)) * BITS_PER_BYTE;
					values[11] = CStringGetTextDatum(
													 bits_to_text(tuphdr->t_bits, bits_len));
				}
				else
					nulls[11] = true;

				if (tuphdr->t_infomask & HEAP_HASOID_OLD)
					values[12] = HeapTupleHeaderGetOidOld(tuphdr);
				else
					nulls[12] = true;
			}
			else
			{
				nulls[11] = true;
				nulls[12] = true;
			}
		}
		else
		{
			/*
			 * The line pointer is not used, or it's invalid. Set the rest of
			 * the fields to NULL
			 */
			int			i;

			for (i = 4; i <= 13; i++)
				nulls[i] = true;
		}

		/* Build and return the result tuple. */
		resultTuple = heap_form_tuple(inter_call_data->tupd, values, nulls);
		result = HeapTupleGetDatum(resultTuple);

		inter_call_data->offset++;

		SRF_RETURN_NEXT(fctx, result);
	}
	else
		SRF_RETURN_DONE(fctx);
}
Exemplo n.º 11
0
/*
 * Create a new PLyProcedure structure
 */
static PLyProcedure *
PLy_procedure_create(HeapTuple procTup, Oid fn_oid, bool is_trigger)
{
	char		procName[NAMEDATALEN + 256];
	Form_pg_proc procStruct;
	PLyProcedure *volatile proc;
	MemoryContext cxt;
	MemoryContext oldcxt;
	int			rv;
	char	   *ptr;

	procStruct = (Form_pg_proc) GETSTRUCT(procTup);
	rv = snprintf(procName, sizeof(procName),
				  "__plpython_procedure_%s_%u",
				  NameStr(procStruct->proname),
				  fn_oid);
	if (rv >= sizeof(procName) || rv < 0)
		elog(ERROR, "procedure name would overrun buffer");

	/* Replace any not-legal-in-Python-names characters with '_' */
	for (ptr = procName; *ptr; ptr++)
	{
		if (!((*ptr >= 'A' && *ptr <= 'Z') ||
			  (*ptr >= 'a' && *ptr <= 'z') ||
			  (*ptr >= '0' && *ptr <= '9')))
			*ptr = '_';
	}

	/* Create long-lived context that all procedure info will live in */
	cxt = AllocSetContextCreateExtended(TopMemoryContext,
										procName,
										MEMCONTEXT_COPY_NAME,
										ALLOCSET_DEFAULT_SIZES);

	oldcxt = MemoryContextSwitchTo(cxt);

	proc = (PLyProcedure *) palloc0(sizeof(PLyProcedure));
	proc->mcxt = cxt;

	PG_TRY();
	{
		Datum		protrftypes_datum;
		Datum		prosrcdatum;
		bool		isnull;
		char	   *procSource;
		int			i;

		proc->proname = pstrdup(NameStr(procStruct->proname));
		proc->pyname = pstrdup(procName);
		proc->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
		proc->fn_tid = procTup->t_self;
		proc->fn_readonly = (procStruct->provolatile != PROVOLATILE_VOLATILE);
		proc->is_setof = procStruct->proretset;
		proc->is_procedure = (procStruct->prorettype == InvalidOid);
		proc->src = NULL;
		proc->argnames = NULL;
		proc->args = NULL;
		proc->nargs = 0;
		proc->langid = procStruct->prolang;
		protrftypes_datum = SysCacheGetAttr(PROCOID, procTup,
											Anum_pg_proc_protrftypes,
											&isnull);
		proc->trftypes = isnull ? NIL : oid_array_to_list(protrftypes_datum);
		proc->code = NULL;
		proc->statics = NULL;
		proc->globals = NULL;
		proc->calldepth = 0;
		proc->argstack = NULL;

		/*
		 * get information required for output conversion of the return value,
		 * but only if this isn't a trigger or procedure.
		 */
		if (!is_trigger && procStruct->prorettype)
		{
			Oid			rettype = procStruct->prorettype;
			HeapTuple	rvTypeTup;
			Form_pg_type rvTypeStruct;

			rvTypeTup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(rettype));
			if (!HeapTupleIsValid(rvTypeTup))
				elog(ERROR, "cache lookup failed for type %u", rettype);
			rvTypeStruct = (Form_pg_type) GETSTRUCT(rvTypeTup);

			/* Disallow pseudotype result, except for void or record */
			if (rvTypeStruct->typtype == TYPTYPE_PSEUDO)
			{
				if (rettype == VOIDOID ||
					rettype == RECORDOID)
					 /* okay */ ;
				else if (rettype == TRIGGEROID || rettype == EVTTRIGGEROID)
					ereport(ERROR,
							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
							 errmsg("trigger functions can only be called as triggers")));
				else
					ereport(ERROR,
							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
							 errmsg("PL/Python functions cannot return type %s",
									format_type_be(rettype))));
			}

			/* set up output function for procedure result */
			PLy_output_setup_func(&proc->result, proc->mcxt,
								  rettype, -1, proc);

			ReleaseSysCache(rvTypeTup);
		}
		else
		{
			/*
			 * In a trigger function, we use proc->result and proc->result_in
			 * for converting tuples, but we don't yet have enough info to set
			 * them up.  PLy_exec_trigger will deal with it.
			 */
			proc->result.typoid = InvalidOid;
			proc->result_in.typoid = InvalidOid;
		}

		/*
		 * Now get information required for input conversion of the
		 * procedure's arguments.  Note that we ignore output arguments here.
		 * If the function returns record, those I/O functions will be set up
		 * when the function is first called.
		 */
		if (procStruct->pronargs)
		{
			Oid		   *types;
			char	  **names,
					   *modes;
			int			pos,
						total;

			/* extract argument type info from the pg_proc tuple */
			total = get_func_arg_info(procTup, &types, &names, &modes);

			/* count number of in+inout args into proc->nargs */
			if (modes == NULL)
				proc->nargs = total;
			else
			{
				/* proc->nargs was initialized to 0 above */
				for (i = 0; i < total; i++)
				{
					if (modes[i] != PROARGMODE_OUT &&
						modes[i] != PROARGMODE_TABLE)
						(proc->nargs)++;
				}
			}

			/* Allocate arrays for per-input-argument data */
			proc->argnames = (char **) palloc0(sizeof(char *) * proc->nargs);
			proc->args = (PLyDatumToOb *) palloc0(sizeof(PLyDatumToOb) * proc->nargs);

			for (i = pos = 0; i < total; i++)
			{
				HeapTuple	argTypeTup;
				Form_pg_type argTypeStruct;

				if (modes &&
					(modes[i] == PROARGMODE_OUT ||
					 modes[i] == PROARGMODE_TABLE))
					continue;	/* skip OUT arguments */

				Assert(types[i] == procStruct->proargtypes.values[pos]);

				argTypeTup = SearchSysCache1(TYPEOID,
											 ObjectIdGetDatum(types[i]));
				if (!HeapTupleIsValid(argTypeTup))
					elog(ERROR, "cache lookup failed for type %u", types[i]);
				argTypeStruct = (Form_pg_type) GETSTRUCT(argTypeTup);

				/* disallow pseudotype arguments */
				if (argTypeStruct->typtype == TYPTYPE_PSEUDO)
					ereport(ERROR,
							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
							 errmsg("PL/Python functions cannot accept type %s",
									format_type_be(types[i]))));

				/* set up I/O function info */
				PLy_input_setup_func(&proc->args[pos], proc->mcxt,
									 types[i], -1,	/* typmod not known */
									 proc);

				/* get argument name */
				proc->argnames[pos] = names ? pstrdup(names[i]) : NULL;

				ReleaseSysCache(argTypeTup);

				pos++;
			}
		}

		/*
		 * get the text of the function.
		 */
		prosrcdatum = SysCacheGetAttr(PROCOID, procTup,
									  Anum_pg_proc_prosrc, &isnull);
		if (isnull)
			elog(ERROR, "null prosrc");
		procSource = TextDatumGetCString(prosrcdatum);

		PLy_procedure_compile(proc, procSource);

		pfree(procSource);
	}
	PG_CATCH();
	{
		MemoryContextSwitchTo(oldcxt);
		PLy_procedure_delete(proc);
		PG_RE_THROW();
	}
	PG_END_TRY();

	MemoryContextSwitchTo(oldcxt);
	return proc;
}
Exemplo n.º 12
0
void
PLy_output_tuple_funcs(PLyTypeInfo *arg, TupleDesc desc)
{
	int			i;

	if (arg->is_rowtype == 0)
		elog(ERROR, "PLyTypeInfo struct is initialized for a Datum");
	arg->is_rowtype = 1;

	if (arg->out.r.natts != desc->natts)
	{
		if (arg->out.r.atts)
			PLy_free(arg->out.r.atts);
		arg->out.r.natts = desc->natts;
		arg->out.r.atts = PLy_malloc0(desc->natts * sizeof(PLyObToDatum));
	}

	Assert(OidIsValid(desc->tdtypeid));

	/*
	 * RECORDOID means we got called to create output functions for an
	 * anonymous record type
	 */
	if (desc->tdtypeid != RECORDOID)
	{
		HeapTuple	relTup;

		/* Get the pg_class tuple corresponding to the type of the output */
		arg->typ_relid = typeidTypeRelid(desc->tdtypeid);
		relTup = SearchSysCache1(RELOID, ObjectIdGetDatum(arg->typ_relid));
		if (!HeapTupleIsValid(relTup))
			elog(ERROR, "cache lookup failed for relation %u", arg->typ_relid);

		/* Remember XMIN and TID for later validation if cache is still OK */
		arg->typrel_xmin = HeapTupleHeaderGetRawXmin(relTup->t_data);
		arg->typrel_tid = relTup->t_self;

		ReleaseSysCache(relTup);
	}

	for (i = 0; i < desc->natts; i++)
	{
		HeapTuple	typeTup;

		if (desc->attrs[i]->attisdropped)
			continue;

		if (arg->out.r.atts[i].typoid == desc->attrs[i]->atttypid)
			continue;			/* already set up this entry */

		typeTup = SearchSysCache1(TYPEOID,
								  ObjectIdGetDatum(desc->attrs[i]->atttypid));
		if (!HeapTupleIsValid(typeTup))
			elog(ERROR, "cache lookup failed for type %u",
				 desc->attrs[i]->atttypid);

		PLy_output_datum_func2(&(arg->out.r.atts[i]), typeTup);

		ReleaseSysCache(typeTup);
	}
}
Exemplo n.º 13
0
void
PLy_input_tuple_funcs(PLyTypeInfo *arg, TupleDesc desc)
{
	int			i;
	PLyExecutionContext *exec_ctx = PLy_current_execution_context();

	if (arg->is_rowtype == 0)
		elog(ERROR, "PLyTypeInfo struct is initialized for a Datum");
	arg->is_rowtype = 1;

	if (arg->in.r.natts != desc->natts)
	{
		if (arg->in.r.atts)
			PLy_free(arg->in.r.atts);
		arg->in.r.natts = desc->natts;
		arg->in.r.atts = PLy_malloc0(desc->natts * sizeof(PLyDatumToOb));
	}

	/* Can this be an unnamed tuple? If not, then an Assert would be enough */
	if (desc->tdtypmod != -1)
		elog(ERROR, "received unnamed record type as input");

	Assert(OidIsValid(desc->tdtypeid));

	/*
	 * RECORDOID means we got called to create input functions for a tuple
	 * fetched by plpy.execute or for an anonymous record type
	 */
	if (desc->tdtypeid != RECORDOID)
	{
		HeapTuple	relTup;

		/* Get the pg_class tuple corresponding to the type of the input */
		arg->typ_relid = typeidTypeRelid(desc->tdtypeid);
		relTup = SearchSysCache1(RELOID, ObjectIdGetDatum(arg->typ_relid));
		if (!HeapTupleIsValid(relTup))
			elog(ERROR, "cache lookup failed for relation %u", arg->typ_relid);

		/* Remember XMIN and TID for later validation if cache is still OK */
		arg->typrel_xmin = HeapTupleHeaderGetRawXmin(relTup->t_data);
		arg->typrel_tid = relTup->t_self;

		ReleaseSysCache(relTup);
	}

	for (i = 0; i < desc->natts; i++)
	{
		HeapTuple	typeTup;

		if (desc->attrs[i]->attisdropped)
			continue;

		if (arg->in.r.atts[i].typoid == desc->attrs[i]->atttypid)
			continue;			/* already set up this entry */

		typeTup = SearchSysCache1(TYPEOID,
								  ObjectIdGetDatum(desc->attrs[i]->atttypid));
		if (!HeapTupleIsValid(typeTup))
			elog(ERROR, "cache lookup failed for type %u",
				 desc->attrs[i]->atttypid);

		PLy_input_datum_func2(&(arg->in.r.atts[i]),
							  desc->attrs[i]->atttypid,
							  typeTup,
							  exec_ctx->curr_proc->langid,
							  exec_ctx->curr_proc->trftypes);

		ReleaseSysCache(typeTup);
	}
}