Exemple #1
0
/*
 * ProcessCatchupEvent
 *
 * Respond to a catchup event (PROCSIG_CATCHUP_INTERRUPT) from another
 * backend.
 *
 * This is called either directly from the PROCSIG_CATCHUP_INTERRUPT
 * signal handler, or the next time control reaches the outer idle loop
 * (assuming there's still anything to do by then).
 */
static void
ProcessCatchupEvent(void)
{
	bool		notify_enabled;
	bool		client_wait_timeout_enabled;
	DtxContext  saveDistributedTransactionContext;

	/*
	 * Funny indentation to keep the code inside identical to upstream
	 * while at the same time supporting CMockery which has problems with
	 * multiple bracing on column 1.
	 */
	PG_TRY();
	{
	in_process_catchup_event = 1;

	/* Must prevent SIGUSR2 and SIGALRM(for IdleSessionGangTimeout) interrupt while I am running */
	notify_enabled = DisableNotifyInterrupt();
	client_wait_timeout_enabled = DisableClientWaitTimeoutInterrupt();

	/*
	 * What we need to do here is cause ReceiveSharedInvalidMessages() to run,
	 * which will do the necessary work and also reset the
	 * catchupInterruptOccurred flag.  If we are inside a transaction we can
	 * just call AcceptInvalidationMessages() to do this.  If we aren't, we
	 * start and immediately end a transaction; the call to
	 * AcceptInvalidationMessages() happens down inside transaction start.
	 *
	 * It is awfully tempting to just call AcceptInvalidationMessages()
	 * without the rest of the xact start/stop overhead, and I think that
	 * would actually work in the normal case; but I am not sure that things
	 * would clean up nicely if we got an error partway through.
	 */
	if (IsTransactionOrTransactionBlock())
	{
		elog(DEBUG1, "ProcessCatchupEvent inside transaction");
		AcceptInvalidationMessages();
	}
	else
	{
		elog(DEBUG1, "ProcessCatchupEvent outside transaction");

		/*
		 * Save distributed transaction context first.
		 */
		saveDistributedTransactionContext = DistributedTransactionContext;
		DistributedTransactionContext = DTX_CONTEXT_LOCAL_ONLY;

		StartTransactionCommand();
		CommitTransactionCommand();

		DistributedTransactionContext = saveDistributedTransactionContext;
	}

	if (notify_enabled)
		EnableNotifyInterrupt();

	if (client_wait_timeout_enabled)
		EnableClientWaitTimeoutInterrupt();

	in_process_catchup_event = 0;
	}
	PG_CATCH();
	{
		in_process_catchup_event = 0;
		PG_RE_THROW();
	}
	PG_END_TRY();
}
Exemple #2
0
static Datum
PLyMapping_ToComposite(PLyObToDatum *arg, TupleDesc desc, PyObject *mapping)
{
	Datum		result;
	HeapTuple	tuple;
	Datum	   *values;
	bool	   *nulls;
	volatile int i;

	Assert(PyMapping_Check(mapping));

	/* Build tuple */
	values = palloc(sizeof(Datum) * desc->natts);
	nulls = palloc(sizeof(bool) * desc->natts);
	for (i = 0; i < desc->natts; ++i)
	{
		char	   *key;
		PyObject   *volatile value;
		PLyObToDatum *att;
		Form_pg_attribute attr = TupleDescAttr(desc, i);

		if (attr->attisdropped)
		{
			values[i] = (Datum) 0;
			nulls[i] = true;
			continue;
		}

		key = NameStr(attr->attname);
		value = NULL;
		att = &arg->u.tuple.atts[i];
		PG_TRY();
		{
			value = PyMapping_GetItemString(mapping, key);
			if (!value)
				ereport(ERROR,
						(errcode(ERRCODE_UNDEFINED_COLUMN),
						 errmsg("key \"%s\" not found in mapping", key),
						 errhint("To return null in a column, "
								 "add the value None to the mapping with the key named after the column.")));

			values[i] = att->func(att, value, &nulls[i], false);

			Py_XDECREF(value);
			value = NULL;
		}
		PG_CATCH();
		{
			Py_XDECREF(value);
			PG_RE_THROW();
		}
		PG_END_TRY();
	}

	tuple = heap_form_tuple(desc, values, nulls);
	result = heap_copy_tuple_as_datum(tuple, desc);
	heap_freetuple(tuple);

	pfree(values);
	pfree(nulls);

	return result;
}
Exemple #3
0
static Datum
PLyGenericObject_ToComposite(PLyObToDatum *arg, TupleDesc desc, PyObject *object, bool inarray)
{
	Datum		result;
	HeapTuple	tuple;
	Datum	   *values;
	bool	   *nulls;
	volatile int i;

	/* Build tuple */
	values = palloc(sizeof(Datum) * desc->natts);
	nulls = palloc(sizeof(bool) * desc->natts);
	for (i = 0; i < desc->natts; ++i)
	{
		char	   *key;
		PyObject   *volatile value;
		PLyObToDatum *att;
		Form_pg_attribute attr = TupleDescAttr(desc, i);

		if (attr->attisdropped)
		{
			values[i] = (Datum) 0;
			nulls[i] = true;
			continue;
		}

		key = NameStr(attr->attname);
		value = NULL;
		att = &arg->u.tuple.atts[i];
		PG_TRY();
		{
			value = PyObject_GetAttrString(object, key);
			if (!value)
			{
				/*
				 * No attribute for this column in the object.
				 *
				 * If we are parsing a composite type in an array, a likely
				 * cause is that the function contained something like "[[123,
				 * 'foo']]". Before PostgreSQL 10, that was interpreted as an
				 * array, with a composite type (123, 'foo') in it. But now
				 * it's interpreted as a two-dimensional array, and we try to
				 * interpret "123" as the composite type. See also similar
				 * heuristic in PLyObject_ToScalar().
				 */
				ereport(ERROR,
						(errcode(ERRCODE_UNDEFINED_COLUMN),
						 errmsg("attribute \"%s\" does not exist in Python object", key),
						 inarray ?
						 errhint("To return a composite type in an array, return the composite type as a Python tuple, e.g., \"[('foo',)]\".") :
						 errhint("To return null in a column, let the returned object have an attribute named after column with value None.")));
			}

			values[i] = att->func(att, value, &nulls[i], false);

			Py_XDECREF(value);
			value = NULL;
		}
		PG_CATCH();
		{
			Py_XDECREF(value);
			PG_RE_THROW();
		}
		PG_END_TRY();
	}

	tuple = heap_form_tuple(desc, values, nulls);
	result = heap_copy_tuple_as_datum(tuple, desc);
	heap_freetuple(tuple);

	pfree(values);
	pfree(nulls);

	return result;
}
Exemple #4
0
/*
 * PersistHoldablePortal
 *
 * Prepare the specified Portal for access outside of the current
 * transaction. When this function returns, all future accesses to the
 * portal must be done via the Tuplestore (not by invoking the
 * executor).
 */
void
PersistHoldablePortal(Portal portal)
{
	QueryDesc  *queryDesc = PortalGetQueryDesc(portal);
	Portal		saveActivePortal;
	ResourceOwner saveResourceOwner;
	MemoryContext savePortalContext;
	MemoryContext oldcxt;

	/*
	 * If we're preserving a holdable portal, we had better be inside the
	 * transaction that originally created it.
	 */
	Assert(portal->createSubid != InvalidSubTransactionId);
	Assert(queryDesc != NULL);

	/*
	 * Caller must have created the tuplestore already.
	 */
	Assert(portal->holdContext != NULL);
	Assert(portal->holdStore != NULL);

	/*
	 * Before closing down the executor, we must copy the tupdesc into
	 * long-term memory, since it was created in executor memory.
	 */
	oldcxt = MemoryContextSwitchTo(portal->holdContext);

	portal->tupDesc = CreateTupleDescCopy(portal->tupDesc);

	MemoryContextSwitchTo(oldcxt);

	/*
	 * Check for improper portal use, and mark portal active.
	 */
	if (portal->status != PORTAL_READY)
		ereport(ERROR,
				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
				 errmsg("portal \"%s\" cannot be run", portal->name)));
	portal->status = PORTAL_ACTIVE;

	/*
	 * Set up global portal context pointers.
	 */
	saveActivePortal = ActivePortal;
	saveResourceOwner = CurrentResourceOwner;
	savePortalContext = PortalContext;
	PG_TRY();
	{
		ActivePortal = portal;
		if (portal->resowner)
			CurrentResourceOwner = portal->resowner;
		PortalContext = PortalGetHeapMemory(portal);

		MemoryContextSwitchTo(PortalContext);

		PushActiveSnapshot(queryDesc->snapshot);

		/*
		 * Rewind the executor: we need to store the entire result set in the
		 * tuplestore, so that subsequent backward FETCHs can be processed.
		 */
		ExecutorRewind(queryDesc);

		/*
		 * Change the destination to output to the tuplestore.	Note we tell
		 * the tuplestore receiver to detoast all data passed through it.
		 */
		queryDesc->dest = CreateDestReceiver(DestTuplestore);
		SetTuplestoreDestReceiverParams(queryDesc->dest,
										portal->holdStore,
										portal->holdContext,
										true);

		/* Fetch the result set into the tuplestore */
		ExecutorRun(queryDesc, ForwardScanDirection, 0L);

		(*queryDesc->dest->rDestroy) (queryDesc->dest);
		queryDesc->dest = NULL;

		/*
		 * Now shut down the inner executor.
		 */
		portal->queryDesc = NULL;		/* prevent double shutdown */
		ExecutorFinish(queryDesc);
		ExecutorEnd(queryDesc);
		FreeQueryDesc(queryDesc);

		/*
		 * Set the position in the result set.
		 */
		MemoryContextSwitchTo(portal->holdContext);

		if (portal->atEnd)
		{
			/*
			 * We can handle this case even if posOverflow: just force the
			 * tuplestore forward to its end.  The size of the skip request
			 * here is arbitrary.
			 */
			while (tuplestore_skiptuples(portal->holdStore, 1000000, true))
				 /* continue */ ;
		}
		else
		{
			if (portal->posOverflow)	/* oops, cannot trust portalPos */
				ereport(ERROR,
						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
						 errmsg("could not reposition held cursor")));

			tuplestore_rescan(portal->holdStore);

			if (!tuplestore_skiptuples(portal->holdStore,
									   portal->portalPos,
									   true))
				elog(ERROR, "unexpected end of tuple stream");
		}
	}
	PG_CATCH();
	{
		/* Uncaught error while executing portal: mark it dead */
		MarkPortalFailed(portal);

		/* Restore global vars and propagate error */
		ActivePortal = saveActivePortal;
		CurrentResourceOwner = saveResourceOwner;
		PortalContext = savePortalContext;

		PG_RE_THROW();
	}
	PG_END_TRY();

	MemoryContextSwitchTo(oldcxt);

	/* Mark portal not active */
	portal->status = PORTAL_READY;

	ActivePortal = saveActivePortal;
	CurrentResourceOwner = saveResourceOwner;
	PortalContext = savePortalContext;

	PopActiveSnapshot();

	/*
	 * We can now release any subsidiary memory of the portal's heap context;
	 * we'll never use it again.  The executor already dropped its context,
	 * but this will clean up anything that glommed onto the portal's heap via
	 * PortalContext.
	 */
	MemoryContextDeleteChildren(PortalGetHeapMemory(portal));
}
Exemple #5
0
/*
 * Internal version of the CacheRelease function
 *
 * Unregisters the entry from the cleanup list if requested.
 */
static void
Cache_ReleaseCached(Cache *cache, CacheEntry *entry, bool unregisterCleanup)
{
	Assert(NULL != cache);
	Assert(NULL != entry);

	Cache_ComputeEntryHashcode(cache, entry);

	volatile CacheAnchor *anchor = SyncHTLookup(cache->syncHashtable, &entry->hashvalue);
	Assert(anchor != NULL);

	/* Acquire anchor lock to touch the entry */
	SpinLockAcquire(&anchor->spinlock);

	uint32 pinCount = Cache_EntryDecRef(cache, entry);
	bool deleteEntry = false;

	if (pinCount == 0 && entry->state == CACHE_ENTRY_DELETED)
	{
		/* Delete the cache entry if pin-count = 0 and it is marked for deletion */
		Cache_UnlinkEntry(cache, (CacheAnchor *) anchor, entry);
		deleteEntry = true;

		Cache_DecPerfCounter(&cache->cacheHdr->cacheStats.noDeletedEntries, 1 /* delta */);
	}

	SpinLockRelease(&anchor->spinlock);

	/*
	 * Releasing anchor to hashtable.
	 * Ignoring 'removed' return value, both values are valid
	 */
	SyncHTRelease(cache->syncHashtable, (void *) anchor);

	/* If requested, unregister entry from the cleanup list */
	if (unregisterCleanup)
	{
		Cache_UnregisterCleanup(cache, entry);
	}

	if (deleteEntry)
	{

		PG_TRY();
		{
			/* Call client-specific cleanup function before removing entry from cache */
			cache->cleanupEntry(CACHE_ENTRY_PAYLOAD(entry));
		}
		PG_CATCH();
		{

			/* Grab entry lock to ensure exclusive access to it while we're touching it */
			Cache_LockEntry(cache, entry);

			entry->state = CACHE_ENTRY_FREE;

#ifdef USE_ASSERT_CHECKING
			Cache_MemsetPayload(cache, entry);
#endif

			Cache_UnlockEntry(cache, entry);

			/* Link entry back in the freelist */
			Cache_AddToFreelist(cache, entry);

			PG_RE_THROW();
		}
		PG_END_TRY();

		/* Grab entry lock to ensure exclusive access to it while we're touching it */
		Cache_LockEntry(cache, entry);

		entry->state = CACHE_ENTRY_FREE;

#ifdef USE_ASSERT_CHECKING
		Cache_MemsetPayload(cache, entry);
#endif

		Cache_UnlockEntry(cache, entry);

		/* Link entry back in the freelist */
		Cache_AddToFreelist(cache, entry);
	}
}
Exemple #6
0
/*
 * Helper function for the various SQL callable logical decoding functions.
 */
static Datum
pg_logical_slot_get_changes_guts(FunctionCallInfo fcinfo, bool confirm, bool binary)
{
	Name		name = PG_GETARG_NAME(0);
	XLogRecPtr	upto_lsn;
	int32		upto_nchanges;

	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
	MemoryContext per_query_ctx;
	MemoryContext oldcontext;

	XLogRecPtr	end_of_wal;
	XLogRecPtr	startptr;

	LogicalDecodingContext *ctx;

	ResourceOwner old_resowner = CurrentResourceOwner;
	ArrayType  *arr;
	Size		ndim;
	List	   *options = NIL;
	DecodingOutputState *p;

	if (PG_ARGISNULL(1))
		upto_lsn = InvalidXLogRecPtr;
	else
		upto_lsn = PG_GETARG_LSN(1);

	if (PG_ARGISNULL(2))
		upto_nchanges = InvalidXLogRecPtr;
	else
		upto_nchanges = PG_GETARG_INT32(2);

	/* check to see if caller supports us returning a tuplestore */
	if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("set-valued function called in context that cannot accept a set")));
	if (!(rsinfo->allowedModes & SFRM_Materialize))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("materialize mode required, but it is not allowed in this context")));

	/* state to write output to */
	p = palloc0(sizeof(DecodingOutputState));

	p->binary_output = binary;

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

	check_permissions();

	CheckLogicalDecodingRequirements();

	arr = PG_GETARG_ARRAYTYPE_P(3);
	ndim = ARR_NDIM(arr);

	per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
	oldcontext = MemoryContextSwitchTo(per_query_ctx);

	if (ndim > 1)
	{
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("array must be one-dimensional")));
	}
	else if (array_contains_nulls(arr))
	{
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("array must not contain nulls")));
	}
	else if (ndim == 1)
	{
		int			nelems;
		Datum	   *datum_opts;
		int			i;

		Assert(ARR_ELEMTYPE(arr) == TEXTOID);

		deconstruct_array(arr, TEXTOID, -1, false, 'i',
						  &datum_opts, NULL, &nelems);

		if (nelems % 2 != 0)
			ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					 errmsg("array must have even number of elements")));

		for (i = 0; i < nelems; i += 2)
		{
			char	   *name = TextDatumGetCString(datum_opts[i]);
			char	   *opt = TextDatumGetCString(datum_opts[i + 1]);

			options = lappend(options, makeDefElem(name, (Node *) makeString(opt)));
		}
	}

	p->tupstore = tuplestore_begin_heap(true, false, work_mem);
	rsinfo->returnMode = SFRM_Materialize;
	rsinfo->setResult = p->tupstore;
	rsinfo->setDesc = p->tupdesc;

	/* compute the current end-of-wal */
	if (!RecoveryInProgress())
		end_of_wal = GetFlushRecPtr();
	else
		end_of_wal = GetXLogReplayRecPtr(NULL);

	CheckLogicalDecodingRequirements();
	ReplicationSlotAcquire(NameStr(*name));

	PG_TRY();
	{
		ctx = CreateDecodingContext(InvalidXLogRecPtr,
									options,
									logical_read_local_xlog_page,
									LogicalOutputPrepareWrite,
									LogicalOutputWrite);

		MemoryContextSwitchTo(oldcontext);

		/*
		 * Check whether the output pluggin writes textual output if that's
		 * what we need.
		 */
		if (!binary &&
			ctx->options.output_type != OUTPUT_PLUGIN_TEXTUAL_OUTPUT)
			ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					 errmsg("output plugin cannot produce binary output")));

		ctx->output_writer_private = p;

		startptr = MyReplicationSlot->data.restart_lsn;

		CurrentResourceOwner = ResourceOwnerCreate(CurrentResourceOwner, "logical decoding");

		/* invalidate non-timetravel entries */
		InvalidateSystemCaches();

		while ((startptr != InvalidXLogRecPtr && startptr < end_of_wal) ||
			   (ctx->reader->EndRecPtr && ctx->reader->EndRecPtr < end_of_wal))
		{
			XLogRecord *record;
			char	   *errm = NULL;

			record = XLogReadRecord(ctx->reader, startptr, &errm);
			if (errm)
				elog(ERROR, "%s", errm);

			startptr = InvalidXLogRecPtr;

			/*
			 * The {begin_txn,change,commit_txn}_wrapper callbacks above will
			 * store the description into our tuplestore.
			 */
			if (record != NULL)
				LogicalDecodingProcessRecord(ctx, record);

			/* check limits */
			if (upto_lsn != InvalidXLogRecPtr &&
				upto_lsn <= ctx->reader->EndRecPtr)
				break;
			if (upto_nchanges != 0 &&
				upto_nchanges <= p->returned_rows)
				break;
		}
	}
	PG_CATCH();
	{
		/* clear all timetravel entries */
		InvalidateSystemCaches();

		PG_RE_THROW();
	}
	PG_END_TRY();

	tuplestore_donestoring(tupstore);

	CurrentResourceOwner = old_resowner;

	/*
	 * Next time, start where we left off. (Hunting things, the family
	 * business..)
	 */
	if (ctx->reader->EndRecPtr != InvalidXLogRecPtr && confirm)
		LogicalConfirmReceivedLocation(ctx->reader->EndRecPtr);

	/* free context, call shutdown callback */
	FreeDecodingContext(ctx);

	ReplicationSlotRelease();
	InvalidateSystemCaches();

	return (Datum) 0;
}
Exemple #7
0
static void
call_graph_fmgr_hook(FmgrHookEventType event,
			  FmgrInfo *flinfo, Datum *args)
{
	bool aborted = false;
	EdgeHashKey key;
	EdgeHashElem *elem;
	instr_time current_time;

	if (next_fmgr_hook)
		(*next_fmgr_hook) (event, flinfo, args);

	INSTR_TIME_SET_CURRENT(current_time);

	switch (event)
	{
		case FHET_START:
		{
			bool found;

			if (call_stack == NIL)
			{
				top_level_function_oid = flinfo->fn_oid;

				/* We're about to enter the top level function; check whether we've been disabled */
				if (!enable_call_graph)
				{
					tracking_current_graph = false;
					recursion_depth = 1;
					return;
				}

				/* Start tracking the call graph; we need to create the hash table */
				create_edge_hash_table();
				tracking_current_graph = true;

				/* If we're tracking table usage, take a stat snapshot now */
				if (track_table_usage)
					table_stat_snapshot = get_table_stat_snapshot();

				/* Use InvalidOid for the imaginary edge into the top level function */
				key.caller = InvalidOid;
			}
			else
			{
				if (!tracking_current_graph)
				{
					/*
					 * Not tracking this graph, just see whether we've recursed into the top level function
					 * (see the comments near the beginning of the file)
					 */
					if (flinfo->fn_oid == top_level_function_oid)
						recursion_depth++;

					return;
				}

				elem = linitial(call_stack);

				/* Calculate the self time we spent in the previous function (elem->key.callee in this case). */
				INSTR_TIME_ACCUM_DIFF(elem->self_time, current_time, current_self_time_start);

				key.caller = elem->key.callee;
			}

			key.callee = flinfo->fn_oid;

			elem = hash_search(edge_hash_table, (void *) &key, HASH_ENTER, &found);
			if (found)
				elem->num_calls++;
			else
			{
				elem->key = key;
				elem->num_calls = 1;
				INSTR_TIME_SET_ZERO(elem->total_time);
				INSTR_TIME_SET_ZERO(elem->self_time);
			}

			call_stack = lcons(elem, call_stack);

			INSTR_TIME_SET_CURRENT(elem->total_time_start);
			memcpy(&current_self_time_start, &elem->total_time_start, sizeof(instr_time));
		}
			break;

		/*
		 * In both ABORT and END cases we pop off the last element from the call stack, and if the stack
		 * is empty, we process the data we gathered.
		 *
		 * XXX for some reason if the top level function aborted SPI won't work correctly.
		 */
		case FHET_ABORT:
			aborted = true;

		case FHET_END:
			/*
			 * If we're not tracking this particular graph, we only need to see whether we're done
			 * with the graph or not.
			 */
			if (!tracking_current_graph)
			{
				if (top_level_function_oid == flinfo->fn_oid)
				{
					recursion_depth--;
					if (recursion_depth == 0)
						top_level_function_oid = InvalidOid;
				}

				Assert(table_stat_snapshot == NULL);
				return;
			}

			Assert(((EdgeHashElem *) linitial(call_stack))->key.callee == flinfo->fn_oid);

			elem = linitial(call_stack);
			INSTR_TIME_ACCUM_DIFF(elem->self_time, current_time, current_self_time_start);
			INSTR_TIME_ACCUM_DIFF(elem->total_time, current_time, elem->total_time_start);

			call_stack = list_delete_first(call_stack);

			if (call_stack != NIL)
			{
				/* we're going back to the previous node, start recording its self_time */
				INSTR_TIME_SET_CURRENT(current_self_time_start);
				break;
			}

			/*
			 * At this point we're done with the graph.  If the top level function exited cleanly, we can
			 * process the data we've gathered in the hash table and add that data into the buffer table.
			 */
			if (!aborted)
			{
				/*
				 * It is in some cases possible that process_edge_data() throws an exception.  We really need to
				 * clean up our state in case that happens.
				 */
				PG_TRY();
				{
					Datum buffer_id = assign_callgraph_buffer_id();

					/* Better check both conditions here */
					if (table_stat_snapshot && track_table_usage)
						insert_snapshot_delta(buffer_id, table_stat_snapshot);

					process_edge_data(buffer_id);
				}
				PG_CATCH();
				{
					if (table_stat_snapshot)
					{
						release_table_stat_snapshot(table_stat_snapshot);
						table_stat_snapshot = NULL;
					}

					destroy_edge_hash_table();
					top_level_function_oid = InvalidOid;
					PG_RE_THROW();
				}
				PG_END_TRY();
			}

			if (table_stat_snapshot)
			{
				release_table_stat_snapshot(table_stat_snapshot);
				table_stat_snapshot = NULL;
			}

			destroy_edge_hash_table();
			top_level_function_oid = InvalidOid;

			break;
		default:
			elog(ERROR, "Unknown FmgrHookEventType %d", event);
			return;
	}
}
Exemple #8
0
int send_alert_from_chunks(const PipeProtoChunk *chunk,
		const PipeProtoChunk * saved_chunks_in)
{

	int ret = -1;
	GpErrorData errorData;

	CSVChunkStr chunkstr =
	{ chunk, chunk->data + sizeof(GpErrorDataFixFields) };

	memset(&errorData, 0, sizeof(errorData));

	memcpy(&errorData.fix_fields, chunk->data, sizeof(errorData.fix_fields));

	if (chunk == NULL)
		return -1;
	if (chunk->hdr.len == 0)
		return -1;
	if (chunk->hdr.zero != 0)
		return -1;

	if (chunk->hdr.log_format != 'c')
		elog(ERROR,"send_alert_from_chunks only works when CSV logging is enabled");

	errorData.username = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.databasename = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.remote_host = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.remote_port = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_severity = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.sql_state = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_message = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_detail = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_hint = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.internal_query = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_context = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.debug_query_string = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_func_name = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.error_filename = get_str_from_chunk(&chunkstr,saved_chunks_in);
	errorData.stacktrace = get_str_from_chunk(&chunkstr,saved_chunks_in);


	PG_TRY();
	{
	ret = send_alert(&errorData);
	}
	PG_CATCH();
	{
		elog(LOG,"send_alert failed.  Not sending the alert");
		free(errorData.stacktrace ); errorData.stacktrace = NULL;
		free((char *)errorData.error_filename ); errorData.error_filename = NULL;
		free((char *)errorData.error_func_name ); errorData.error_func_name = NULL;
		free(errorData.debug_query_string ); errorData.debug_query_string = NULL;
		free(errorData.error_context); errorData.error_context = NULL;
		free(errorData.internal_query ); errorData.internal_query = NULL;
		free(errorData.error_hint ); errorData.error_hint = NULL;
		free(errorData.error_detail ); errorData.error_detail = NULL;
		free(errorData.error_message ); errorData.error_message = NULL;
		free(errorData.sql_state ); errorData.sql_state = NULL;
		free((char *)errorData.error_severity ); errorData.error_severity = NULL;
		free(errorData.remote_port ); errorData.remote_port = NULL;
		free(errorData.remote_host ); errorData.remote_host = NULL;
		free(errorData.databasename ); errorData.databasename = NULL;
		free(errorData.username ); errorData.username = NULL;
		/* Carry on with error handling. */
		PG_RE_THROW();
	}
	PG_END_TRY();

	// Don't forget to free them!  Best in reverse order of the mallocs.

	free(errorData.stacktrace ); errorData.stacktrace = NULL;
	free((char *)errorData.error_filename ); errorData.error_filename = NULL;
	free((char *)errorData.error_func_name ); errorData.error_func_name = NULL;
	free(errorData.debug_query_string ); errorData.debug_query_string = NULL;
	free(errorData.error_context); errorData.error_context = NULL;
	free(errorData.internal_query ); errorData.internal_query = NULL;
	free(errorData.error_hint ); errorData.error_hint = NULL;
	free(errorData.error_detail ); errorData.error_detail = NULL;
	free(errorData.error_message ); errorData.error_message = NULL;
	free(errorData.sql_state ); errorData.sql_state = NULL;
	free((char *)errorData.error_severity ); errorData.error_severity = NULL;
	free(errorData.remote_port ); errorData.remote_port = NULL;
	free(errorData.remote_host ); errorData.remote_host = NULL;
	free(errorData.databasename ); errorData.databasename = NULL;
	free(errorData.username ); errorData.username = NULL;

	return ret;
}
/*
 * Function used a side effect to simulate throwing exception 
 * by a certain function. 
 */
void
throw_exception_side_effect()
{
  PG_RE_THROW();
}
Exemple #10
0
/*
 * Create a new file set
 *   type is the WorkFileType for the files: BUFFILE or BFZ
 *   can_be_reused: if set to false, then we don't insert this set into the cache,
 *     since the caller is telling us there is no point. This can happen for
 *     example when spilling during index creation.
 *   ps is the PlanState for the subtree rooted at the operator
 *   snapshot contains snapshot information for the current transaction
 *
 */
workfile_set *
workfile_mgr_create_set(enum ExecWorkFileType type, bool can_be_reused, PlanState *ps, workfile_set_snapshot snapshot)
{
	Assert(NULL != workfile_mgr_cache);

	Plan *plan = NULL;
	if (ps != NULL)
	{
		plan = ps->plan;
	}

	AssertImply(can_be_reused, plan != NULL);

	NodeTag node_type = T_Invalid;
	if (ps != NULL)
	{
		node_type = ps->type;
	}
	char *dir_path = create_workset_directory(node_type, currentSliceId);

	/* Create parameter info for the populate function */
	workset_info set_info;
	set_info.file_type = type;
	set_info.snapshot = snapshot;
	set_info.nodeType = node_type;
	set_info.can_be_reused = can_be_reused && workfile_mgr_is_reusable(ps);
	set_info.dir_path = dir_path;
	set_info.session_start_time = GetCurrentTimestamp();
	set_info.operator_work_mem = get_operator_work_mem(ps);
	set_info.on_disk = true;

	CacheEntry *newEntry = NULL;

	PG_TRY();
	{
		newEntry = acquire_entry_retry(workfile_mgr_cache, &set_info);
	}
	PG_CATCH();
	{
		/* Failed to acquire new entry, cache full. Clean up the directory we created. */
		workfile_mgr_delete_set_directory(dir_path);
		PG_RE_THROW();
	}
	PG_END_TRY();

	/* Path has now been copied to the workfile_set. We can free it */
	pfree(dir_path);

	/* Complete initialization of the entry with post-acquire actions */
	Assert(NULL != newEntry);
	workfile_set *work_set = CACHE_ENTRY_PAYLOAD(newEntry);
	Assert(work_set != NULL);
	if (work_set->can_be_reused)
	{
		Assert(plan != NULL);
		Assert(nodeTag(plan) >= T_Plan && nodeTag(plan) < T_PlanInvalItem);

		workfile_set_plan *s_plan = workfile_mgr_serialize_plan(ps);
		work_set->key = workfile_mgr_hash_key(s_plan);
		workfile_mgr_save_plan(work_set, s_plan);
		workfile_mgr_free_plan(s_plan);
	}

	elog(gp_workfile_caching_loglevel, "new spill file set. key=0x%x can_be_reused=%d prefix=%s opMemKB=" INT64_FORMAT,
			work_set->key, work_set->can_be_reused, work_set->path, work_set->metadata.operator_work_mem);

	return work_set;
}
Exemple #11
0
/*
 * ExecRefreshMatView -- execute a REFRESH MATERIALIZED VIEW command
 *
 * This refreshes the materialized view by creating a new table and swapping
 * the relfilenodes of the new table and the old materialized view, so the OID
 * of the original materialized view is preserved. Thus we do not lose GRANT
 * nor references to this materialized view.
 *
 * If WITH NO DATA was specified, this is effectively like a TRUNCATE;
 * otherwise it is like a TRUNCATE followed by an INSERT using the SELECT
 * statement associated with the materialized view.  The statement node's
 * skipData field shows whether the clause was used.
 *
 * Indexes are rebuilt too, via REINDEX. Since we are effectively bulk-loading
 * the new heap, it's better to create the indexes afterwards than to fill them
 * incrementally while we load.
 *
 * The matview's "populated" state is changed based on whether the contents
 * reflect the result set of the materialized view's query.
 */
ObjectAddress
ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
				   ParamListInfo params, char *completionTag)
{
	Oid			matviewOid;
	Relation	matviewRel;
	RewriteRule *rule;
	List	   *actions;
	Query	   *dataQuery;
	Oid			tableSpace;
	Oid			relowner;
	Oid			OIDNewHeap;
	DestReceiver *dest;
	bool		concurrent;
	LOCKMODE	lockmode;
	char		relpersistence;
	Oid			save_userid;
	int			save_sec_context;
	int			save_nestlevel;
	ObjectAddress address;

	/* Determine strength of lock needed. */
	concurrent = stmt->concurrent;
	lockmode = concurrent ? ExclusiveLock : AccessExclusiveLock;

	/*
	 * Get a lock until end of transaction.
	 */
	matviewOid = RangeVarGetRelidExtended(stmt->relation,
										  lockmode, false, false,
										  RangeVarCallbackOwnsTable, NULL);
	matviewRel = heap_open(matviewOid, NoLock);

	/* Make sure it is a materialized view. */
	if (matviewRel->rd_rel->relkind != RELKIND_MATVIEW)
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("\"%s\" is not a materialized view",
						RelationGetRelationName(matviewRel))));

	/* Check that CONCURRENTLY is not specified if not populated. */
	if (concurrent && !RelationIsPopulated(matviewRel))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("CONCURRENTLY cannot be used when the materialized view is not populated")));

	/* Check that conflicting options have not been specified. */
	if (concurrent && stmt->skipData)
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
				 errmsg("CONCURRENTLY and WITH NO DATA options cannot be used together")));

	/* We don't allow an oid column for a materialized view. */
	Assert(!matviewRel->rd_rel->relhasoids);

	/*
	 * Check that everything is correct for a refresh. Problems at this point
	 * are internal errors, so elog is sufficient.
	 */
	if (matviewRel->rd_rel->relhasrules == false ||
		matviewRel->rd_rules->numLocks < 1)
		elog(ERROR,
			 "materialized view \"%s\" is missing rewrite information",
			 RelationGetRelationName(matviewRel));

	if (matviewRel->rd_rules->numLocks > 1)
		elog(ERROR,
			 "materialized view \"%s\" has too many rules",
			 RelationGetRelationName(matviewRel));

	rule = matviewRel->rd_rules->rules[0];
	if (rule->event != CMD_SELECT || !(rule->isInstead))
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a SELECT INSTEAD OF rule",
			 RelationGetRelationName(matviewRel));

	actions = rule->actions;
	if (list_length(actions) != 1)
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a single action",
			 RelationGetRelationName(matviewRel));

	/*
	 * The stored query was rewritten at the time of the MV definition, but
	 * has not been scribbled on by the planner.
	 */
	dataQuery = (Query *) linitial(actions);
	Assert(IsA(dataQuery, Query));

	/*
	 * Check for active uses of the relation in the current transaction, such
	 * as open scans.
	 *
	 * NB: We count on this to protect us against problems with refreshing the
	 * data using HEAP_INSERT_FROZEN.
	 */
	CheckTableNotInUse(matviewRel, "REFRESH MATERIALIZED VIEW");

	/*
	 * Tentatively mark the matview as populated or not (this will roll back
	 * if we fail later).
	 */
	SetMatViewPopulatedState(matviewRel, !stmt->skipData);

	relowner = matviewRel->rd_rel->relowner;

	/*
	 * Switch to the owner's userid, so that any functions are run as that
	 * user.  Also arrange to make GUC variable changes local to this command.
	 * Don't lock it down too tight to create a temporary table just yet.  We
	 * will switch modes when we are about to execute user code.
	 */
	GetUserIdAndSecContext(&save_userid, &save_sec_context);
	SetUserIdAndSecContext(relowner,
						   save_sec_context | SECURITY_LOCAL_USERID_CHANGE);
	save_nestlevel = NewGUCNestLevel();

	/* Concurrent refresh builds new data in temp tablespace, and does diff. */
	if (concurrent)
	{
		tableSpace = GetDefaultTablespace(RELPERSISTENCE_TEMP);
		relpersistence = RELPERSISTENCE_TEMP;
	}
	else
	{
		tableSpace = matviewRel->rd_rel->reltablespace;
		relpersistence = matviewRel->rd_rel->relpersistence;
	}

	/*
	 * Create the transient table that will receive the regenerated data. Lock
	 * it against access by any other process until commit (by which time it
	 * will be gone).
	 */
	OIDNewHeap = make_new_heap(matviewOid, tableSpace, relpersistence,
							   ExclusiveLock);
	LockRelationOid(OIDNewHeap, AccessExclusiveLock);
	dest = CreateTransientRelDestReceiver(OIDNewHeap);

	/*
	 * Now lock down security-restricted operations.
	 */
	SetUserIdAndSecContext(relowner,
						   save_sec_context | SECURITY_RESTRICTED_OPERATION);

	/* Generate the data, if wanted. */
	if (!stmt->skipData)
		refresh_matview_datafill(dest, dataQuery, queryString);

	heap_close(matviewRel, NoLock);

	/* Make the matview match the newly generated data. */
	if (concurrent)
	{
		int			old_depth = matview_maintenance_depth;

		PG_TRY();
		{
			refresh_by_match_merge(matviewOid, OIDNewHeap, relowner,
								   save_sec_context);
		}
		PG_CATCH();
		{
			matview_maintenance_depth = old_depth;
			PG_RE_THROW();
		}
		PG_END_TRY();
		Assert(matview_maintenance_depth == old_depth);
	}
	else
		refresh_by_heap_swap(matviewOid, OIDNewHeap, relpersistence);

	/* Roll back any GUC changes */
	AtEOXact_GUC(false, save_nestlevel);

	/* Restore userid and security context */
	SetUserIdAndSecContext(save_userid, save_sec_context);

	ObjectAddressSet(address, RelationRelationId, matviewOid);

	return address;
}
/*
 * ExecWorkFile_Write
 *    write the given data from the end of the last write position.
 *
 * This function returns true if the write succeeds. Otherwise, return false.
 */
bool
ExecWorkFile_Write(ExecWorkFile *workfile,
				   void *data,
				   uint64 size)
{
	Assert(workfile != NULL);
	uint64 bytes;

	if (data == NULL || size == 0)
	{
		return false;
	}

	/* Test the per-query and per-segment limit */
	if ((workfile->flags & EXEC_WORKFILE_LIMIT_SIZE) &&
			!WorkfileDiskspace_Reserve(size))
	{
		/* Failed to reserve additional disk space, notify caller */
		workfile_mgr_report_error();
	}

	switch(workfile->fileType)
	{
		case BUFFILE:
			{}
			BufFile *buffile = (BufFile *)workfile->file;

			int64 current_size = BufFileGetSize(buffile);
			int64 new_size = 0;

			PG_TRY();
			{
				bytes = BufFileWrite(buffile, data, size);
			}
			PG_CATCH();
			{
				new_size = BufFileGetSize(buffile);
				workfile->size = new_size;
				WorkfileDiskspace_Commit( (new_size - current_size), size, true /* update_query_size */);

				int64 size_evicted = workfile_mgr_evict(MIN_EVICT_SIZE);
				elog(gp_workfile_caching_loglevel, "Hit out of disk space, evicted " INT64_FORMAT " bytes", size_evicted);

				PG_RE_THROW();
			}
			PG_END_TRY();

			new_size = BufFileGetSize(buffile);
			workfile->size = new_size;

			WorkfileDiskspace_Commit( (new_size - current_size), size, true /* update_query_size */);
			workfile_update_in_progress_size(workfile, new_size - current_size);

			if (bytes != size)
			{
				workfile_mgr_report_error();
			}

			break;
		case BFZ:

			PG_TRY();
			{
				bfz_append((bfz_t *)workfile->file, data, size);
			}
			PG_CATCH();
			{
				Assert(WorkfileDiskspace_IsFull());
				WorkfileDiskspace_Commit(0, size, true /* update_query_size */);

				int64 size_evicted = workfile_mgr_evict(MIN_EVICT_SIZE);
				elog(gp_workfile_caching_loglevel, "Hit out of disk space, evicted " INT64_FORMAT " bytes", size_evicted);

				PG_RE_THROW();
			}
			PG_END_TRY();

			/* bfz_append always adds to the file size */
			workfile->size += size;
			if ((workfile->flags & EXEC_WORKFILE_LIMIT_SIZE))
			{
				WorkfileDiskspace_Commit(size, size, true /* update_query_size */);
			}
			workfile_update_in_progress_size(workfile, size);

			break;
		default:
			insist_log(false, "invalid work file type: %d", workfile->fileType);
	}

	return true;
}
Exemple #13
0
/*
 * Emit a PG error or notice, together with any available info about
 * the current Python error, previously set by PLy_exception_set().
 * This should be used to propagate Python errors into PG.  If fmt is
 * NULL, the Python error becomes the primary error message, otherwise
 * it becomes the detail.  If there is a Python traceback, it is put
 * in the context.
 */
void
PLy_elog(int elevel, const char *fmt,...)
{
	char	   *xmsg;
	char	   *tbmsg;
	int			tb_depth;
	StringInfoData emsg;
	PyObject   *exc,
			   *val,
			   *tb;
	const char *primary = NULL;
	int			sqlerrcode = 0;
	char	   *detail = NULL;
	char	   *hint = NULL;
	char	   *query = NULL;
	int			position = 0;

	PyErr_Fetch(&exc, &val, &tb);

	if (exc != NULL)
	{
		PyErr_NormalizeException(&exc, &val, &tb);

		if (PyErr_GivenExceptionMatches(val, PLy_exc_spi_error))
			PLy_get_spi_error_data(val, &sqlerrcode, &detail, &hint, &query, &position);
		else if (PyErr_GivenExceptionMatches(val, PLy_exc_fatal))
			elevel = FATAL;
	}

	/* this releases our refcount on tb! */
	PLy_traceback(exc, val, tb,
				  &xmsg, &tbmsg, &tb_depth);

	if (fmt)
	{
		initStringInfo(&emsg);
		for (;;)
		{
			va_list		ap;
			int			needed;

			va_start(ap, fmt);
			needed = appendStringInfoVA(&emsg, dgettext(TEXTDOMAIN, fmt), ap);
			va_end(ap);
			if (needed == 0)
				break;
			enlargeStringInfo(&emsg, needed);
		}
		primary = emsg.data;

		/* Since we have a format string, we cannot have a SPI detail. */
		Assert(detail == NULL);

		/* If there's an exception message, it goes in the detail. */
		if (xmsg)
			detail = xmsg;
	}
	else
	{
		if (xmsg)
			primary = xmsg;
	}

	PG_TRY();
	{
		ereport(elevel,
				(errcode(sqlerrcode ? sqlerrcode : ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
			  errmsg_internal("%s", primary ? primary : "no exception data"),
				 (detail) ? errdetail_internal("%s", detail) : 0,
				 (tb_depth > 0 && tbmsg) ? errcontext("%s", tbmsg) : 0,
				 (hint) ? errhint("%s", hint) : 0,
				 (query) ? internalerrquery(query) : 0,
				 (position) ? internalerrposition(position) : 0));
	}
	PG_CATCH();
	{
		if (fmt)
			pfree(emsg.data);
		if (xmsg)
			pfree(xmsg);
		if (tbmsg)
			pfree(tbmsg);
		Py_XDECREF(exc);
		Py_XDECREF(val);

		PG_RE_THROW();
	}
	PG_END_TRY();

	if (fmt)
		pfree(emsg.data);
	if (xmsg)
		pfree(xmsg);
	if (tbmsg)
		pfree(tbmsg);
	Py_XDECREF(exc);
	Py_XDECREF(val);
}
Exemple #14
0
/*
 * Extract a Python traceback from the given exception data.
 *
 * The exception error message is returned in xmsg, the traceback in
 * tbmsg (both as palloc'd strings) and the traceback depth in
 * tb_depth.
 *
 * We release refcounts on all the Python objects in the traceback stack,
 * but not on e or v.
 */
static void
PLy_traceback(PyObject *e, PyObject *v, PyObject *tb,
			  char **xmsg, char **tbmsg, int *tb_depth)
{
	PyObject   *e_type_o;
	PyObject   *e_module_o;
	char	   *e_type_s = NULL;
	char	   *e_module_s = NULL;
	PyObject   *vob = NULL;
	char	   *vstr;
	StringInfoData xstr;
	StringInfoData tbstr;

	/*
	 * if no exception, return nulls
	 */
	if (e == NULL)
	{
		*xmsg = NULL;
		*tbmsg = NULL;
		*tb_depth = 0;

		return;
	}

	/*
	 * Format the exception and its value and put it in xmsg.
	 */

	e_type_o = PyObject_GetAttrString(e, "__name__");
	e_module_o = PyObject_GetAttrString(e, "__module__");
	if (e_type_o)
		e_type_s = PyString_AsString(e_type_o);
	if (e_type_s)
		e_module_s = PyString_AsString(e_module_o);

	if (v && ((vob = PyObject_Str(v)) != NULL))
		vstr = PyString_AsString(vob);
	else
		vstr = "unknown";

	initStringInfo(&xstr);
	if (!e_type_s || !e_module_s)
	{
		if (PyString_Check(e))
			/* deprecated string exceptions */
			appendStringInfoString(&xstr, PyString_AsString(e));
		else
			/* shouldn't happen */
			appendStringInfoString(&xstr, "unrecognized exception");
	}
	/* mimics behavior of traceback.format_exception_only */
	else if (strcmp(e_module_s, "builtins") == 0
			 || strcmp(e_module_s, "__main__") == 0
			 || strcmp(e_module_s, "exceptions") == 0)
		appendStringInfo(&xstr, "%s", e_type_s);
	else
		appendStringInfo(&xstr, "%s.%s", e_module_s, e_type_s);
	appendStringInfo(&xstr, ": %s", vstr);

	*xmsg = xstr.data;

	/*
	 * Now format the traceback and put it in tbmsg.
	 */

	*tb_depth = 0;
	initStringInfo(&tbstr);
	/* Mimick Python traceback reporting as close as possible. */
	appendStringInfoString(&tbstr, "Traceback (most recent call last):");
	while (tb != NULL && tb != Py_None)
	{
		PyObject   *volatile tb_prev = NULL;
		PyObject   *volatile frame = NULL;
		PyObject   *volatile code = NULL;
		PyObject   *volatile name = NULL;
		PyObject   *volatile lineno = NULL;
		PyObject   *volatile filename = NULL;

		PG_TRY();
		{
			/*
			 * Ancient versions of Python (circa 2.3) contain a bug whereby
			 * the fetches below can fail if the error indicator is set.
			 */
			PyErr_Clear();

			lineno = PyObject_GetAttrString(tb, "tb_lineno");
			if (lineno == NULL)
				elog(ERROR, "could not get line number from Python traceback");

			frame = PyObject_GetAttrString(tb, "tb_frame");
			if (frame == NULL)
				elog(ERROR, "could not get frame from Python traceback");

			code = PyObject_GetAttrString(frame, "f_code");
			if (code == NULL)
				elog(ERROR, "could not get code object from Python frame");

			name = PyObject_GetAttrString(code, "co_name");
			if (name == NULL)
				elog(ERROR, "could not get function name from Python code object");

			filename = PyObject_GetAttrString(code, "co_filename");
			if (filename == NULL)
				elog(ERROR, "could not get file name from Python code object");
		}
		PG_CATCH();
		{
			Py_XDECREF(frame);
			Py_XDECREF(code);
			Py_XDECREF(name);
			Py_XDECREF(lineno);
			Py_XDECREF(filename);
			PG_RE_THROW();
		}
		PG_END_TRY();

		/* The first frame always points at <module>, skip it. */
		if (*tb_depth > 0)
		{
			PLyExecutionContext *exec_ctx = PLy_current_execution_context();
			char	   *proname;
			char	   *fname;
			char	   *line;
			char	   *plain_filename;
			long		plain_lineno;

			/*
			 * The second frame points at the internal function, but to mimick
			 * Python error reporting we want to say <module>.
			 */
			if (*tb_depth == 1)
				fname = "<module>";
			else
				fname = PyString_AsString(name);

			proname = PLy_procedure_name(exec_ctx->curr_proc);
			plain_filename = PyString_AsString(filename);
			plain_lineno = PyInt_AsLong(lineno);

			if (proname == NULL)
				appendStringInfo(
				&tbstr, "\n  PL/Python anonymous code block, line %ld, in %s",
								 plain_lineno - 1, fname);
			else
				appendStringInfo(
					&tbstr, "\n  PL/Python function \"%s\", line %ld, in %s",
								 proname, plain_lineno - 1, fname);

			/*
			 * function code object was compiled with "<string>" as the
			 * filename
			 */
			if (exec_ctx->curr_proc && plain_filename != NULL &&
				strcmp(plain_filename, "<string>") == 0)
			{
				/*
				 * If we know the current procedure, append the exact line
				 * from the source, again mimicking Python's traceback.py
				 * module behavior.  We could store the already line-split
				 * source to avoid splitting it every time, but producing a
				 * traceback is not the most important scenario to optimize
				 * for.  But we do not go as far as traceback.py in reading
				 * the source of imported modules.
				 */
				line = get_source_line(exec_ctx->curr_proc->src, plain_lineno);
				if (line)
				{
					appendStringInfo(&tbstr, "\n    %s", line);
					pfree(line);
				}
			}
		}

		Py_DECREF(frame);
		Py_DECREF(code);
		Py_DECREF(name);
		Py_DECREF(lineno);
		Py_DECREF(filename);

		/* Release the current frame and go to the next one. */
		tb_prev = tb;
		tb = PyObject_GetAttrString(tb, "tb_next");
		Assert(tb_prev != Py_None);
		Py_DECREF(tb_prev);
		if (tb == NULL)
			elog(ERROR, "could not traverse Python traceback");
		(*tb_depth)++;
	}

	/* Return the traceback. */
	*tbmsg = tbstr.data;

	Py_XDECREF(e_type_o);
	Py_XDECREF(e_module_o);
	Py_XDECREF(vob);
}
Exemple #15
0
/*
 * This is used when a process is waiting for its counterpart to attach to the
 * queue.  We exit when the other process attaches as expected, or, if
 * handle != NULL, when the referenced background process or the postmaster
 * dies.  Note that if handle == NULL, and the process fails to attach, we'll
 * potentially get stuck here forever waiting for a process that may never
 * start.  We do check for interrupts, though.
 *
 * ptr is a pointer to the memory address that we're expecting to become
 * non-NULL when our counterpart attaches to the queue.
 */
static bool
shm_mq_wait_internal(volatile shm_mq *mq, PGPROC *volatile * ptr,
					 BackgroundWorkerHandle *handle)
{
	bool		save_set_latch_on_sigusr1;
	bool		result = false;

	save_set_latch_on_sigusr1 = set_latch_on_sigusr1;
	if (handle != NULL)
		set_latch_on_sigusr1 = true;

	PG_TRY();
	{
		for (;;)
		{
			BgwHandleStatus status;
			pid_t		pid;
			bool		detached;

			/* Acquire the lock just long enough to check the pointer. */
			SpinLockAcquire(&mq->mq_mutex);
			detached = mq->mq_detached;
			result = (*ptr != NULL);
			SpinLockRelease(&mq->mq_mutex);

			/* Fail if detached; else succeed if initialized. */
			if (detached)
			{
				result = false;
				break;
			}
			if (result)
				break;

			if (handle != NULL)
			{
				/* Check for unexpected worker death. */
				status = GetBackgroundWorkerPid(handle, &pid);
				if (status != BGWH_STARTED && status != BGWH_NOT_YET_STARTED)
				{
					result = false;
					break;
				}
			}

			/* Wait to be signalled. */
			WaitLatch(&MyProc->procLatch, WL_LATCH_SET, 0);

			/* Reset the latch so we don't spin. */
			ResetLatch(&MyProc->procLatch);

			/* An interrupt may have occurred while we were waiting. */
			CHECK_FOR_INTERRUPTS();
		}
	}
	PG_CATCH();
	{
		set_latch_on_sigusr1 = save_set_latch_on_sigusr1;
		PG_RE_THROW();
	}
	PG_END_TRY();

	return result;
}
Exemple #16
0
/* --------------------------------
 *		pq_getmessage	- get a message with length word from connection
 *
 *		The return value is placed in an expansible StringInfo, which has
 *		already been initialized by the caller.
 *		Only the message body is placed in the StringInfo; the length word
 *		is removed.  Also, s->cursor is initialized to zero for convenience
 *		in scanning the message contents.
 *
 *		If maxlen is not zero, it is an upper limit on the length of the
 *		message we are willing to accept.  We abort the connection (by
 *		returning EOF) if client tries to send more than that.
 *
 *		returns 0 if OK, EOF if trouble
 * --------------------------------
 */
int
pq_getmessage(StringInfo s, int maxlen)
{
	int32		len;

	resetStringInfo(s);

	/* Read message length word */
	if (pq_getbytes((char *) &len, 4) == EOF)
	{
		ereport(COMMERROR,
				(errcode(ERRCODE_PROTOCOL_VIOLATION),
				 errmsg("unexpected EOF within message length word")));
		return EOF;
	}

	len = ntohl(len);

	if (len < 4 ||
		(maxlen > 0 && len > maxlen))
	{
		ereport(COMMERROR,
				(errcode(ERRCODE_PROTOCOL_VIOLATION),
				 errmsg("invalid message length")));
		return EOF;
	}

	len -= 4;					/* discount length itself */

	if (len > 0)
	{
		/*
		 * Allocate space for message.	If we run out of room (ridiculously
		 * large message), we will elog(ERROR), but we want to discard the
		 * message body so as not to lose communication sync.
		 */
		PG_TRY();
		{
			enlargeStringInfo(s, len);
		}
		PG_CATCH();
		{
			if (pq_discardbytes(len) == EOF)
				ereport(COMMERROR,
						(errcode(ERRCODE_PROTOCOL_VIOLATION),
						 errmsg("incomplete message from client")));
			PG_RE_THROW();
		}
		PG_END_TRY();

		/* And grab the message */
		if (pq_getbytes(s->data, len) == EOF)
		{
			ereport(COMMERROR,
					(errcode(ERRCODE_PROTOCOL_VIOLATION),
					 errmsg("incomplete message from client")));
			return EOF;
		}
		s->len = len;
		/* Place a trailing null per StringInfo convention */
		s->data[len] = '\0';
	}

	return 0;
}
/*
 * This method will emulate the real ExceptionalCondition
 * function by re-throwing the exception, essentially falling
 * back to the next available PG_CATCH();
 */
void
_ExceptionalCondition()
{
     PG_RE_THROW();
}
/**
 * @brief Entry point of the user-defined function for pg_bulkload.
 * @return Returns number of loaded tuples.  If the case of errors, -1 will be
 * returned.
 */
Datum
pg_bulkload(PG_FUNCTION_ARGS)
{
	Reader		   *rd = NULL;
	Writer		   *wt = NULL;
	Datum			options;
	MemoryContext	ctx;
	MemoryContext	ccxt;
	PGRUsage		ru0;
	PGRUsage		ru1;
	int64			count;
	int64			parse_errors;
	int64			skip;
	WriterResult	ret;
	char		   *start;
	char		   *end;
	float8			system;
	float8			user;
	float8			duration;
	TupleDesc		tupdesc;
	Datum			values[PG_BULKLOAD_COLS];
	bool			nulls[PG_BULKLOAD_COLS];
	HeapTuple		result;

	/* 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");

	BULKLOAD_PROFILE_PUSH();

	pg_rusage_init(&ru0);

	/* must be the super user */
	if (!superuser())
		ereport(ERROR,
			(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
			 errmsg("must be superuser to use pg_bulkload")));

	options = PG_GETARG_DATUM(0);

	ccxt = CurrentMemoryContext;

	/*
	 * STEP 1: Initialization
	 */

	/* parse options and create reader and writer */
	ParseOptions(options, &rd, &wt, ru0.tv.tv_sec);

	/* initialize reader */
	ReaderInit(rd);

	/*
	 * We need to split PG_TRY block because gcc optimizes if-branches with
	 * longjmp codes too much. Local variables initialized in either branch
	 * cannot be handled another branch.
	 */
	PG_TRY();
	{
		/* truncate heap */
		if (wt->truncate)
			TruncateTable(wt->relid);

		/* initialize writer */
		WriterInit(wt);

		/* initialize checker */
		CheckerInit(&rd->checker, wt->rel, wt->tchecker);

		/* initialize parser */
		ParserInit(rd->parser, &rd->checker, rd->infile, wt->desc,
				   wt->multi_process, PG_GET_COLLATION());
	}
	PG_CATCH();
	{
		if (rd)
			ReaderClose(rd, true);
		if (wt)
			WriterClose(wt, true);
		PG_RE_THROW();
	}
	PG_END_TRY();

	/* No throwable codes here! */

	PG_TRY();
	{
		/* create logger */
		CreateLogger(rd->logfile, wt->verbose, rd->infile[0] == ':');

		start = timeval_to_cstring(ru0.tv);
		LoggerLog(INFO, "\npg_bulkload %s on %s\n\n",
				   PG_BULKLOAD_VERSION, start);

		ReaderDumpParams(rd);
		WriterDumpParams(wt);
		LoggerLog(INFO, "\n");

		BULKLOAD_PROFILE(&prof_init);

		/*
		 * STEP 2: Build heap
		 */

		/* Switch into its memory context */
		Assert(wt->context);
		ctx = MemoryContextSwitchTo(wt->context);

		/* Loop for each input file record. */
		while (wt->count < rd->limit)
		{
			HeapTuple	tuple;

			CHECK_FOR_INTERRUPTS();

			/* read tuple */
			BULKLOAD_PROFILE_PUSH();
			tuple = ReaderNext(rd);
			BULKLOAD_PROFILE_POP();
			BULKLOAD_PROFILE(&prof_reader);
			if (tuple == NULL)
				break;

			/* write tuple */
			BULKLOAD_PROFILE_PUSH();
			WriterInsert(wt, tuple);
			wt->count += 1;
			BULKLOAD_PROFILE_POP();
			BULKLOAD_PROFILE(&prof_writer);

			MemoryContextReset(wt->context);
			BULKLOAD_PROFILE(&prof_reset);
		}

		MemoryContextSwitchTo(ctx);

		/*
		 * STEP 3: Finalize heap and merge indexes
		 */

		count = wt->count;
		parse_errors = rd->parse_errors;

		/*
		 * close writer first and reader second because shmem_exit callback
		 * is managed by a simple stack.
		 */
		ret = WriterClose(wt, false);
		wt = NULL;
		skip = ReaderClose(rd, false);
		rd = NULL;
	}
	PG_CATCH();
	{
		ErrorData	   *errdata;
		MemoryContext	ecxt;

		ecxt = MemoryContextSwitchTo(ccxt);
		errdata = CopyErrorData();
		LoggerLog(INFO, "%s\n", errdata->message);
		FreeErrorData(errdata);

		/* close writer first, and reader second */
		if (wt)
			WriterClose(wt, true);
		if (rd)
			ReaderClose(rd, true);

		MemoryContextSwitchTo(ecxt);
		PG_RE_THROW();
	}
	PG_END_TRY();

	count -= ret.num_dup_new;

	LoggerLog(INFO, "\n"
			  "  " int64_FMT " Rows skipped.\n"
			  "  " int64_FMT " Rows successfully loaded.\n"
			  "  " int64_FMT " Rows not loaded due to parse errors.\n"
			  "  " int64_FMT " Rows not loaded due to duplicate errors.\n"
			  "  " int64_FMT " Rows replaced with new rows.\n\n",
			  skip, count, parse_errors, ret.num_dup_new, ret.num_dup_old);

	pg_rusage_init(&ru1);
	system = diffTime(ru1.ru.ru_stime, ru0.ru.ru_stime);
	user = diffTime(ru1.ru.ru_utime, ru0.ru.ru_utime);
	duration = diffTime(ru1.tv, ru0.tv);
	end = timeval_to_cstring(ru1.tv);

	memset(nulls, 0, sizeof(nulls));
	values[0] = Int64GetDatum(skip);
	values[1] = Int64GetDatum(count);
	values[2] = Int64GetDatum(parse_errors);
	values[3] = Int64GetDatum(ret.num_dup_new);
	values[4] = Int64GetDatum(ret.num_dup_old);
	values[5] = Float8GetDatumFast(system);
	values[6] = Float8GetDatumFast(user);
	values[7] = Float8GetDatumFast(duration);

	LoggerLog(INFO,
		"Run began on %s\n"
		"Run ended on %s\n\n"
		"CPU %.2fs/%.2fu sec elapsed %.2f sec\n",
		start, end, system, user, duration);

	LoggerClose();

	result = heap_form_tuple(tupdesc, values, nulls);

	BULKLOAD_PROFILE(&prof_fini);
	BULKLOAD_PROFILE_POP();
	BULKLOAD_PROFILE_PRINT();

	PG_RETURN_DATUM(HeapTupleGetDatum(result));
}
Exemple #19
0
/*
 * initTrie  - create trie from file.
 *
 * Function converts UTF8-encoded file into current encoding.
 */
static TrieChar *
initTrie(const char *filename)
{
	TrieChar   *volatile rootTrie = NULL;
	MemoryContext ccxt = CurrentMemoryContext;
	tsearch_readline_state trst;
	volatile bool skip;

	filename = get_tsearch_config_filename(filename, "rules");
	if (!tsearch_readline_begin(&trst, filename))
		ereport(ERROR,
				(errcode(ERRCODE_CONFIG_FILE_ERROR),
				 errmsg("could not open unaccent file \"%s\": %m",
						filename)));

	do
	{
		/*
		 * pg_do_encoding_conversion() (called by tsearch_readline()) will
		 * emit exception if it finds untranslatable characters in current
		 * locale. We just skip such lines, continuing with the next.
		 */
		skip = true;

		PG_TRY();
		{
			char	   *line;

			while ((line = tsearch_readline(&trst)) != NULL)
			{
				/*----------
				 * The format of each line must be "src" or "src trg", where
				 * src and trg are sequences of one or more non-whitespace
				 * characters, separated by whitespace.  Whitespace at start
				 * or end of line is ignored.  If trg is omitted, an empty
				 * string is used as the replacement.
				 *
				 * We use a simple state machine, with states
				 *	0	initial (before src)
				 *	1	in src
				 *	2	in whitespace after src
				 *	3	in trg
				 *	4	in whitespace after trg
				 *	-1	syntax error detected
				 *----------
				 */
				int			state;
				char	   *ptr;
				char	   *src = NULL;
				char	   *trg = NULL;
				int			ptrlen;
				int			srclen = 0;
				int			trglen = 0;

				state = 0;
				for (ptr = line; *ptr; ptr += ptrlen)
				{
					ptrlen = pg_mblen(ptr);
					/* ignore whitespace, but end src or trg */
					if (t_isspace(ptr))
					{
						if (state == 1)
							state = 2;
						else if (state == 3)
							state = 4;
						continue;
					}
					switch (state)
					{
						case 0:
							/* start of src */
							src = ptr;
							srclen = ptrlen;
							state = 1;
							break;
						case 1:
							/* continue src */
							srclen += ptrlen;
							break;
						case 2:
							/* start of trg */
							trg = ptr;
							trglen = ptrlen;
							state = 3;
							break;
						case 3:
							/* continue trg */
							trglen += ptrlen;
							break;
						default:
							/* bogus line format */
							state = -1;
							break;
					}
				}

				if (state == 1 || state == 2)
				{
					/* trg was omitted, so use "" */
					trg = "";
					trglen = 0;
				}

				if (state > 0)
					rootTrie = placeChar(rootTrie,
										 (unsigned char *) src, srclen,
										 trg, trglen);
				else if (state < 0)
					ereport(WARNING,
							(errcode(ERRCODE_CONFIG_FILE_ERROR),
							 errmsg("invalid syntax: more than two strings in unaccent rule")));

				pfree(line);
			}
			skip = false;
		}
		PG_CATCH();
		{
			ErrorData  *errdata;
			MemoryContext ecxt;

			ecxt = MemoryContextSwitchTo(ccxt);
			errdata = CopyErrorData();
			if (errdata->sqlerrcode == ERRCODE_UNTRANSLATABLE_CHARACTER)
			{
				FlushErrorState();
			}
			else
			{
				MemoryContextSwitchTo(ecxt);
				PG_RE_THROW();
			}
		}
		PG_END_TRY();
	}
	while (skip);

	tsearch_readline_end(&trst);

	return rootTrie;
}
Exemple #20
0
/*
 * ExecRefreshMatView -- execute a REFRESH MATERIALIZED VIEW command
 *
 * This refreshes the materialized view by creating a new table and swapping
 * the relfilenodes of the new table and the old materialized view, so the OID
 * of the original materialized view is preserved. Thus we do not lose GRANT
 * nor references to this materialized view.
 *
 * If WITH NO DATA was specified, this is effectively like a TRUNCATE;
 * otherwise it is like a TRUNCATE followed by an INSERT using the SELECT
 * statement associated with the materialized view.  The statement node's
 * skipData field shows whether the clause was used.
 *
 * Indexes are rebuilt too, via REINDEX. Since we are effectively bulk-loading
 * the new heap, it's better to create the indexes afterwards than to fill them
 * incrementally while we load.
 *
 * The matview's "populated" state is changed based on whether the contents
 * reflect the result set of the materialized view's query.
 */
void
ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
				   ParamListInfo params, char *completionTag)
{
	Oid			matviewOid;
	Relation	matviewRel;
	RewriteRule *rule;
	List	   *actions;
	Query	   *dataQuery;
	Oid			tableSpace;
	Oid			owner;
	Oid			OIDNewHeap;
	DestReceiver *dest;
	bool		concurrent;
	LOCKMODE	lockmode;

	/* Determine strength of lock needed. */
	concurrent = stmt->concurrent;
	lockmode = concurrent ? ExclusiveLock : AccessExclusiveLock;

	/*
	 * Get a lock until end of transaction.
	 */
	matviewOid = RangeVarGetRelidExtended(stmt->relation,
										  lockmode, false, false,
										  RangeVarCallbackOwnsTable, NULL);
	matviewRel = heap_open(matviewOid, NoLock);

	/* Make sure it is a materialized view. */
	if (matviewRel->rd_rel->relkind != RELKIND_MATVIEW)
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("\"%s\" is not a materialized view",
						RelationGetRelationName(matviewRel))));

	/* Check that CONCURRENTLY is not specified if not populated. */
	if (concurrent && !RelationIsPopulated(matviewRel))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("CONCURRENTLY cannot be used when the materialized view is not populated")));

	/* Check that conflicting options have not been specified. */
	if (concurrent && stmt->skipData)
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
				 errmsg("CONCURRENTLY and WITH NO DATA options cannot be used together")));

	/* We're not using materialized views in the system catalogs. */
	Assert(!IsSystemRelation(matviewRel));

	/* We don't allow an oid column for a materialized view. */
	Assert(!matviewRel->rd_rel->relhasoids);

	/*
	 * Check that everything is correct for a refresh. Problems at this point
	 * are internal errors, so elog is sufficient.
	 */
	if (matviewRel->rd_rel->relhasrules == false ||
		matviewRel->rd_rules->numLocks < 1)
		elog(ERROR,
			 "materialized view \"%s\" is missing rewrite information",
			 RelationGetRelationName(matviewRel));

	if (matviewRel->rd_rules->numLocks > 1)
		elog(ERROR,
			 "materialized view \"%s\" has too many rules",
			 RelationGetRelationName(matviewRel));

	rule = matviewRel->rd_rules->rules[0];
	if (rule->event != CMD_SELECT || !(rule->isInstead))
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a SELECT INSTEAD OF rule",
			 RelationGetRelationName(matviewRel));

	actions = rule->actions;
	if (list_length(actions) != 1)
		elog(ERROR,
			 "the rule for materialized view \"%s\" is not a single action",
			 RelationGetRelationName(matviewRel));

	/*
	 * The stored query was rewritten at the time of the MV definition, but
	 * has not been scribbled on by the planner.
	 */
	dataQuery = (Query *) linitial(actions);
	Assert(IsA(dataQuery, Query));

	/*
	 * Check for active uses of the relation in the current transaction, such
	 * as open scans.
	 *
	 * NB: We count on this to protect us against problems with refreshing the
	 * data using HEAP_INSERT_FROZEN.
	 */
	CheckTableNotInUse(matviewRel, "REFRESH MATERIALIZED VIEW");

	/*
	 * Tentatively mark the matview as populated or not (this will roll back
	 * if we fail later).
	 */
	SetMatViewPopulatedState(matviewRel, !stmt->skipData);

	/* Concurrent refresh builds new data in temp tablespace, and does diff. */
	if (concurrent)
		tableSpace = GetDefaultTablespace(RELPERSISTENCE_TEMP);
	else
		tableSpace = matviewRel->rd_rel->reltablespace;

	owner = matviewRel->rd_rel->relowner;

	heap_close(matviewRel, NoLock);

	/* Create the transient table that will receive the regenerated data. */
	OIDNewHeap = make_new_heap(matviewOid, tableSpace, concurrent,
							   ExclusiveLock);
	dest = CreateTransientRelDestReceiver(OIDNewHeap);

	/* Generate the data, if wanted. */
	if (!stmt->skipData)
		refresh_matview_datafill(dest, dataQuery, queryString, owner);

	/* Make the matview match the newly generated data. */
	if (concurrent)
	{
		int			old_depth = matview_maintenance_depth;

		PG_TRY();
		{
			refresh_by_match_merge(matviewOid, OIDNewHeap);
		}
		PG_CATCH();
		{
			matview_maintenance_depth = old_depth;
			PG_RE_THROW();
		}
		PG_END_TRY();
		Assert(matview_maintenance_depth == old_depth);
	}
	else
		refresh_by_heap_swap(matviewOid, OIDNewHeap);
}
Exemple #21
0
/* Function passed to testing framework
 * in order to force SetupInterconnect to fail */ 
void
_RETHROW( )
{
	PG_RE_THROW();
}
Exemple #22
0
static PyObject *
PLy_spi_execute_plan(PyObject *ob, PyObject *list, long limit)
{
	volatile int nargs;
	int			i,
				rv;
	PLyPlanObject *plan;
	volatile MemoryContext oldcontext;
	volatile ResourceOwner oldowner;
	PyObject   *ret;

	if (list != NULL)
	{
		if (!PySequence_Check(list) || PyString_Check(list) || PyUnicode_Check(list))
		{
			PLy_exception_set(PyExc_TypeError, "plpy.execute takes a sequence as its second argument");
			return NULL;
		}
		nargs = PySequence_Length(list);
	}
	else
		nargs = 0;

	plan = (PLyPlanObject *) ob;

	if (nargs != plan->nargs)
	{
		char	   *sv;
		PyObject   *so = PyObject_Str(list);

		if (!so)
			PLy_elog(ERROR, "could not execute plan");
		sv = PyString_AsString(so);
		PLy_exception_set_plural(PyExc_TypeError,
							  "Expected sequence of %d argument, got %d: %s",
							 "Expected sequence of %d arguments, got %d: %s",
								 plan->nargs,
								 plan->nargs, nargs, sv);
		Py_DECREF(so);

		return NULL;
	}

	oldcontext = CurrentMemoryContext;
	oldowner = CurrentResourceOwner;

	PLy_spi_subtransaction_begin(oldcontext, oldowner);

	PG_TRY();
	{
		PLyExecutionContext *exec_ctx = PLy_current_execution_context();
		char	   *volatile nulls;
		volatile int j;

		if (nargs > 0)
			nulls = palloc(nargs * sizeof(char));
		else
			nulls = NULL;

		for (j = 0; j < nargs; j++)
		{
			PyObject   *elem;

			elem = PySequence_GetItem(list, j);
			if (elem != Py_None)
			{
				PG_TRY();
				{
					plan->values[j] =
						plan->args[j].out.d.func(&(plan->args[j].out.d),
												 -1,
												 elem);
				}
				PG_CATCH();
				{
					Py_DECREF(elem);
					PG_RE_THROW();
				}
				PG_END_TRY();

				Py_DECREF(elem);
				nulls[j] = ' ';
			}
			else
			{
				Py_DECREF(elem);
				plan->values[j] =
					InputFunctionCall(&(plan->args[j].out.d.typfunc),
									  NULL,
									  plan->args[j].out.d.typioparam,
									  -1);
				nulls[j] = 'n';
			}
		}

		rv = SPI_execute_plan(plan->plan, plan->values, nulls,
							  exec_ctx->curr_proc->fn_readonly, limit);
		ret = PLy_spi_execute_fetch_result(SPI_tuptable, SPI_processed, rv);

		if (nargs > 0)
			pfree(nulls);

		PLy_spi_subtransaction_commit(oldcontext, oldowner);
	}
	PG_CATCH();
	{
		int			k;

		/*
		 * cleanup plan->values array
		 */
		for (k = 0; k < nargs; k++)
		{
			if (!plan->args[k].out.d.typbyval &&
				(plan->values[k] != PointerGetDatum(NULL)))
			{
				pfree(DatumGetPointer(plan->values[k]));
				plan->values[k] = PointerGetDatum(NULL);
			}
		}

		PLy_spi_subtransaction_abort(oldcontext, oldowner);
		return NULL;
	}
	PG_END_TRY();

	for (i = 0; i < nargs; i++)
	{
		if (!plan->args[i].out.d.typbyval &&
			(plan->values[i] != PointerGetDatum(NULL)))
		{
			pfree(DatumGetPointer(plan->values[i]));
			plan->values[i] = PointerGetDatum(NULL);
		}
	}

	if (rv < 0)
	{
		PLy_exception_set(PLy_exc_spi_error,
						  "SPI_execute_plan failed: %s",
						  SPI_result_code_string(rv));
		return NULL;
	}

	return ret;
}
/*
 * ProcessUtility hook
 */
static void
pgss_ProcessUtility(Node *parsetree, const char *queryString,
					ParamListInfo params, bool isTopLevel,
					DestReceiver *dest, char *completionTag)
{
	if (pgss_track_utility && pgss_enabled())
	{
		instr_time	start;
		instr_time	duration;
		uint64		rows = 0;
		BufferUsage bufusage;

		bufusage = pgBufferUsage;
		INSTR_TIME_SET_CURRENT(start);

		nested_level++;
		PG_TRY();
		{
			if (prev_ProcessUtility)
				prev_ProcessUtility(parsetree, queryString, params,
									isTopLevel, dest, completionTag);
			else
				standard_ProcessUtility(parsetree, queryString, params,
										isTopLevel, dest, completionTag);
			nested_level--;
		}
		PG_CATCH();
		{
			nested_level--;
			PG_RE_THROW();
		}
		PG_END_TRY();

		INSTR_TIME_SET_CURRENT(duration);
		INSTR_TIME_SUBTRACT(duration, start);

		/* parse command tag to retrieve the number of affected rows. */
		if (completionTag &&
			sscanf(completionTag, "COPY " UINT64_FORMAT, &rows) != 1)
			rows = 0;

		/* calc differences of buffer counters. */
		bufusage.shared_blks_hit =
			pgBufferUsage.shared_blks_hit - bufusage.shared_blks_hit;
		bufusage.shared_blks_read =
			pgBufferUsage.shared_blks_read - bufusage.shared_blks_read;
		bufusage.shared_blks_written =
			pgBufferUsage.shared_blks_written - bufusage.shared_blks_written;
		bufusage.local_blks_hit =
			pgBufferUsage.local_blks_hit - bufusage.local_blks_hit;
		bufusage.local_blks_read =
			pgBufferUsage.local_blks_read - bufusage.local_blks_read;
		bufusage.local_blks_written =
			pgBufferUsage.local_blks_written - bufusage.local_blks_written;
		bufusage.temp_blks_read =
			pgBufferUsage.temp_blks_read - bufusage.temp_blks_read;
		bufusage.temp_blks_written =
			pgBufferUsage.temp_blks_written - bufusage.temp_blks_written;

		pgss_store(queryString, INSTR_TIME_GET_DOUBLE(duration), rows,
				   &bufusage);
	}
	else
	{
		if (prev_ProcessUtility)
			prev_ProcessUtility(parsetree, queryString, params,
								isTopLevel, dest, completionTag);
		else
			standard_ProcessUtility(parsetree, queryString, params,
									isTopLevel, dest, completionTag);
	}
}
Exemple #24
0
static PyObject *
PLy_spi_execute_fetch_result(SPITupleTable *tuptable, int rows, int status)
{
	PLyResultObject *result;
	volatile MemoryContext oldcontext;

	result = (PLyResultObject *) PLy_result_new();
	Py_DECREF(result->status);
	result->status = PyInt_FromLong(status);

	if (status > 0 && tuptable == NULL)
	{
		Py_DECREF(result->nrows);
		result->nrows = PyInt_FromLong(rows);
	}
	else if (status > 0 && tuptable != NULL)
	{
		PLyTypeInfo args;
		int			i;

		Py_DECREF(result->nrows);
		result->nrows = PyInt_FromLong(rows);
		PLy_typeinfo_init(&args);

		oldcontext = CurrentMemoryContext;
		PG_TRY();
		{
			MemoryContext oldcontext2;

			if (rows)
			{
				Py_DECREF(result->rows);
				result->rows = PyList_New(rows);

				PLy_input_tuple_funcs(&args, tuptable->tupdesc);
				for (i = 0; i < rows; i++)
				{
					PyObject   *row = PLyDict_FromTuple(&args,
														tuptable->vals[i],
														tuptable->tupdesc);

					PyList_SetItem(result->rows, i, row);
				}
			}

			/*
			 * Save tuple descriptor for later use by result set metadata
			 * functions.  Save it in TopMemoryContext so that it survives
			 * outside of an SPI context.  We trust that PLy_result_dealloc()
			 * will clean it up when the time is right.  (Do this as late as
			 * possible, to minimize the number of ways the tupdesc could get
			 * leaked due to errors.)
			 */
			oldcontext2 = MemoryContextSwitchTo(TopMemoryContext);
			result->tupdesc = CreateTupleDescCopy(tuptable->tupdesc);
			MemoryContextSwitchTo(oldcontext2);
		}
		PG_CATCH();
		{
			MemoryContextSwitchTo(oldcontext);
			PLy_typeinfo_dealloc(&args);
			SPI_freetuptable(tuptable);
			Py_DECREF(result);
			PG_RE_THROW();
		}
		PG_END_TRY();

		PLy_typeinfo_dealloc(&args);
		SPI_freetuptable(tuptable);
	}

	return (PyObject *) result;
}
Exemple #25
0
/*
 * Helper function for the various SQL callable logical decoding functions.
 */
static Datum
pg_logical_slot_get_changes_guts(FunctionCallInfo fcinfo, bool confirm, bool binary)
{
    Name		name;
    XLogRecPtr	upto_lsn;
    int32		upto_nchanges;
    ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
    MemoryContext per_query_ctx;
    MemoryContext oldcontext;
    XLogRecPtr	end_of_wal;
    XLogRecPtr	startptr;
    LogicalDecodingContext *ctx;
    ResourceOwner old_resowner = CurrentResourceOwner;
    ArrayType  *arr;
    Size		ndim;
    List	   *options = NIL;
    DecodingOutputState *p;

    check_permissions();

    CheckLogicalDecodingRequirements();

    if (PG_ARGISNULL(0))
        ereport(ERROR,
                (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                 errmsg("slot name must not be null")));
    name = PG_GETARG_NAME(0);

    if (PG_ARGISNULL(1))
        upto_lsn = InvalidXLogRecPtr;
    else
        upto_lsn = PG_GETARG_LSN(1);

    if (PG_ARGISNULL(2))
        upto_nchanges = InvalidXLogRecPtr;
    else
        upto_nchanges = PG_GETARG_INT32(2);

    if (PG_ARGISNULL(3))
        ereport(ERROR,
                (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                 errmsg("options array must not be null")));
    arr = PG_GETARG_ARRAYTYPE_P(3);

    /* check to see if caller supports us returning a tuplestore */
    if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("set-valued function called in context that cannot accept a set")));
    if (!(rsinfo->allowedModes & SFRM_Materialize))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("materialize mode required, but it is not allowed in this context")));

    /* state to write output to */
    p = palloc0(sizeof(DecodingOutputState));

    p->binary_output = binary;

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

    per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
    oldcontext = MemoryContextSwitchTo(per_query_ctx);

    /* Deconstruct options array */
    ndim = ARR_NDIM(arr);
    if (ndim > 1)
    {
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("array must be one-dimensional")));
    }
    else if (array_contains_nulls(arr))
    {
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("array must not contain nulls")));
    }
    else if (ndim == 1)
    {
        int			nelems;
        Datum	   *datum_opts;
        int			i;

        Assert(ARR_ELEMTYPE(arr) == TEXTOID);

        deconstruct_array(arr, TEXTOID, -1, false, 'i',
                          &datum_opts, NULL, &nelems);

        if (nelems % 2 != 0)
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("array must have even number of elements")));

        for (i = 0; i < nelems; i += 2)
        {
            char	   *name = TextDatumGetCString(datum_opts[i]);
            char	   *opt = TextDatumGetCString(datum_opts[i + 1]);

            options = lappend(options, makeDefElem(name, (Node *) makeString(opt), -1));
        }
    }

    p->tupstore = tuplestore_begin_heap(true, false, work_mem);
    rsinfo->returnMode = SFRM_Materialize;
    rsinfo->setResult = p->tupstore;
    rsinfo->setDesc = p->tupdesc;

    /* compute the current end-of-wal */
    if (!RecoveryInProgress())
        end_of_wal = GetFlushRecPtr();
    else
        end_of_wal = GetXLogReplayRecPtr(NULL);

    ReplicationSlotAcquire(NameStr(*name));

    PG_TRY();
    {
        /* restart at slot's confirmed_flush */
        ctx = CreateDecodingContext(InvalidXLogRecPtr,
                                    options,
                                    logical_read_local_xlog_page,
                                    LogicalOutputPrepareWrite,
                                    LogicalOutputWrite);

        MemoryContextSwitchTo(oldcontext);

        /*
         * Check whether the output plugin writes textual output if that's
         * what we need.
         */
        if (!binary &&
                ctx->options.output_type !=OUTPUT_PLUGIN_TEXTUAL_OUTPUT)
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("logical decoding output plugin \"%s\" produces binary output, but function \"%s\" expects textual data",
                            NameStr(MyReplicationSlot->data.plugin),
                            format_procedure(fcinfo->flinfo->fn_oid))));

        ctx->output_writer_private = p;

        /*
         * Decoding of WAL must start at restart_lsn so that the entirety of
         * xacts that committed after the slot's confirmed_flush can be
         * accumulated into reorder buffers.
         */
        startptr = MyReplicationSlot->data.restart_lsn;

        CurrentResourceOwner = ResourceOwnerCreate(CurrentResourceOwner, "logical decoding");

        /* invalidate non-timetravel entries */
        InvalidateSystemCaches();

        while ((startptr != InvalidXLogRecPtr && startptr < end_of_wal) ||
                (ctx->reader->EndRecPtr != InvalidXLogRecPtr && ctx->reader->EndRecPtr < end_of_wal))
        {
            XLogRecord *record;
            char	   *errm = NULL;

            record = XLogReadRecord(ctx->reader, startptr, &errm);
            if (errm)
                elog(ERROR, "%s", errm);

            /*
             * Now that we've set up the xlog reader state, subsequent calls
             * pass InvalidXLogRecPtr to say "continue from last record"
             */
            startptr = InvalidXLogRecPtr;

            /*
             * The {begin_txn,change,commit_txn}_wrapper callbacks above will
             * store the description into our tuplestore.
             */
            if (record != NULL)
                LogicalDecodingProcessRecord(ctx, ctx->reader);

            /* check limits */
            if (upto_lsn != InvalidXLogRecPtr &&
                    upto_lsn <= ctx->reader->EndRecPtr)
                break;
            if (upto_nchanges != 0 &&
                    upto_nchanges <= p->returned_rows)
                break;
            CHECK_FOR_INTERRUPTS();
        }

        tuplestore_donestoring(tupstore);

        CurrentResourceOwner = old_resowner;

        /*
         * Next time, start where we left off. (Hunting things, the family
         * business..)
         */
        if (ctx->reader->EndRecPtr != InvalidXLogRecPtr && confirm)
        {
            LogicalConfirmReceivedLocation(ctx->reader->EndRecPtr);
            /*
             * If only the confirmed_flush_lsn has changed the slot won't get
             * marked as dirty by the above. Callers on the walsender interface
             * are expected to keep track of their own progress and don't need
             * it written out. But SQL-interface users cannot specify their own
             * start positions and it's harder for them to keep track of their
             * progress, so we should make more of an effort to save it for them.
             *
             * Dirty the slot so it's written out at the next checkpoint. We'll
             * still lose its position on crash, as documented, but it's better
             * than always losing the position even on clean restart.
             */
            ReplicationSlotMarkDirty();
        }

        /* free context, call shutdown callback */
        FreeDecodingContext(ctx);

        ReplicationSlotRelease();
        InvalidateSystemCaches();
    }
    PG_CATCH();
    {
        /* clear all timetravel entries */
        InvalidateSystemCaches();

        PG_RE_THROW();
    }
    PG_END_TRY();

    return (Datum) 0;
}
Exemple #26
0
/*
 * Connect to remote server using specified server and user mapping properties.
 */
static PGconn *
connect_pg_server(ForeignServer *server, UserMapping *user)
{
	PGconn	   *volatile conn = NULL;

	/*
	 * Use PG_TRY block to ensure closing connection on error.
	 */
	PG_TRY();
	{
		const char **keywords;
		const char **values;
		int			n;

		/*
		 * Construct connection params from generic options of ForeignServer
		 * and UserMapping.  (Some of them might not be libpq options, in
		 * which case we'll just waste a few array slots.)  Add 3 extra slots
		 * for fallback_application_name, client_encoding, end marker.
		 */
		n = list_length(server->options) + list_length(user->options) + 3;
		keywords = (const char **) palloc(n * sizeof(char *));
		values = (const char **) palloc(n * sizeof(char *));

		n = 0;
		n += ExtractConnectionOptions(server->options,
									  keywords + n, values + n);
		n += ExtractConnectionOptions(user->options,
									  keywords + n, values + n);

		/* Use "postgres_fdw" as fallback_application_name. */
		keywords[n] = "fallback_application_name";
		values[n] = "postgres_fdw";
		n++;

		/* Set client_encoding so that libpq can convert encoding properly. */
		keywords[n] = "client_encoding";
		values[n] = GetDatabaseEncodingName();
		n++;

		keywords[n] = values[n] = NULL;

		/* verify connection parameters and make connection */
		check_conn_params(keywords, values);

		conn = PQconnectdbParams(keywords, values, false);
		if (!conn || PQstatus(conn) != CONNECTION_OK)
		{
			char	   *connmessage;
			int			msglen;

			/* libpq typically appends a newline, strip that */
			connmessage = pstrdup(PQerrorMessage(conn));
			msglen = strlen(connmessage);
			if (msglen > 0 && connmessage[msglen - 1] == '\n')
				connmessage[msglen - 1] = '\0';
			ereport(ERROR,
			   (errcode(ERRCODE_SQLCLIENT_UNABLE_TO_ESTABLISH_SQLCONNECTION),
				errmsg("could not connect to server \"%s\"",
					   server->servername),
				errdetail_internal("%s", connmessage)));
		}

		/*
		 * Check that non-superuser has used password to establish connection;
		 * otherwise, he's piggybacking on the postgres server's user
		 * identity. See also dblink_security_check() in contrib/dblink.
		 */
		if (!superuser() && !PQconnectionUsedPassword(conn))
			ereport(ERROR,
				  (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED),
				   errmsg("password is required"),
				   errdetail("Non-superuser cannot connect if the server does not request a password."),
				   errhint("Target server's authentication method must be changed.")));

		/* Prepare new session for use */
		configure_remote_session(conn);

		pfree(keywords);
		pfree(values);
	}
	PG_CATCH();
	{
		/* Release PGconn data structure if we managed to create one */
		if (conn)
			PQfinish(conn);
		PG_RE_THROW();
	}
	PG_END_TRY();

	return conn;
}
Exemple #27
0
static Datum
PLySequence_ToComposite(PLyObToDatum *arg, TupleDesc desc, PyObject *sequence)
{
	Datum		result;
	HeapTuple	tuple;
	Datum	   *values;
	bool	   *nulls;
	volatile int idx;
	volatile int i;

	Assert(PySequence_Check(sequence));

	/*
	 * Check that sequence length is exactly same as PG tuple's. We actually
	 * can ignore exceeding items or assume missing ones as null but to avoid
	 * plpython developer's errors we are strict here
	 */
	idx = 0;
	for (i = 0; i < desc->natts; i++)
	{
		if (!TupleDescAttr(desc, i)->attisdropped)
			idx++;
	}
	if (PySequence_Length(sequence) != idx)
		ereport(ERROR,
				(errcode(ERRCODE_DATATYPE_MISMATCH),
				 errmsg("length of returned sequence did not match number of columns in row")));

	/* Build tuple */
	values = palloc(sizeof(Datum) * desc->natts);
	nulls = palloc(sizeof(bool) * desc->natts);
	idx = 0;
	for (i = 0; i < desc->natts; ++i)
	{
		PyObject   *volatile value;
		PLyObToDatum *att;

		if (TupleDescAttr(desc, i)->attisdropped)
		{
			values[i] = (Datum) 0;
			nulls[i] = true;
			continue;
		}

		value = NULL;
		att = &arg->u.tuple.atts[i];
		PG_TRY();
		{
			value = PySequence_GetItem(sequence, idx);
			Assert(value);

			values[i] = att->func(att, value, &nulls[i], false);

			Py_XDECREF(value);
			value = NULL;
		}
		PG_CATCH();
		{
			Py_XDECREF(value);
			PG_RE_THROW();
		}
		PG_END_TRY();

		idx++;
	}

	tuple = heap_form_tuple(desc, values, nulls);
	result = heap_copy_tuple_as_datum(tuple, desc);
	heap_freetuple(tuple);

	pfree(values);
	pfree(nulls);

	return result;
}
/*
 * Assign hook routine for "gp_role" option.  This variablle has context
 * PGC_SUSET so that is can only be set by a superuser via the SET command.
 * (It can also be set using an option on postmaster start, but this isn't
 * interesting beccause the derived global CdbRole is always set (along with
 * CdbSessionRole) on backend startup for a new connection.
 *
 * See src/backend/util/misc/guc.c for option definition.
 */
const char *
assign_gp_role(const char *newval, bool doit, GucSource source)
{

#if FALSE
	elog(DEBUG1, "assign_gp_role: gp_role=%s, newval=%s, doit=%s",
		 show_gp_role(), newval, (doit ? "true" : "false"));
#endif


	GpRoleValue newrole = string_to_role(newval);
	GpRoleValue oldrole = Gp_role;

	if (newrole == GP_ROLE_UNDEFINED)
	{
		return NULL;
	}

	if (doit)
	{
		/*
		 * When changing between roles, we must
		 * call cdb_cleanup and then cdb_setup to get
		 * setup and connections appropriate to the new role.
		 */
		bool		do_disconnect = false;
		bool		do_connect = false;

		if (Gp_role != newrole && IsUnderPostmaster)
		{
			if (Gp_role != GP_ROLE_UTILITY)
				do_disconnect = true;

			if (newrole != GP_ROLE_UTILITY)
				do_connect = true;
		}

		if (do_disconnect)
			cdb_cleanup(0,0);

		Gp_role = newrole;

		if (source != PGC_S_DEFAULT)
		{
			if (do_connect)
			{
				/*
				 * In case there are problems with the Greenplum Database tables or data,
				 * we catch any error coming out of cdblink_setup so we can set the
				 * gp_role back to what it was.  Otherwise we may be left with
				 * inappropriate connections for the new role.
				 */
				PG_TRY();
				{
					cdb_setup();
				}
				PG_CATCH();
				{
					cdb_cleanup(0,0);
					Gp_role = oldrole;
					if (Gp_role != GP_ROLE_UTILITY)
						cdb_setup();
					PG_RE_THROW();
				}
				PG_END_TRY();
			}
		}
	}

	return newval;
}
Exemple #29
0
/*
 *	SearchCatCacheList
 *
 *		Generate a list of all tuples matching a partial key (that is,
 *		a key specifying just the first K of the cache's N key columns).
 *
 *		The caller must not modify the list object or the pointed-to tuples,
 *		and must call ReleaseCatCacheList() when done with the list.
 */
CatCList *
SearchCatCacheList(CatCache *cache,
				   int nkeys,
				   Datum v1,
				   Datum v2,
				   Datum v3,
				   Datum v4)
{
	ScanKeyData cur_skey[CATCACHE_MAXKEYS];
	uint32		lHashValue;
	Dlelem	   *elt;
	CatCList   *cl;
	CatCTup    *ct;
	List	   *volatile ctlist;
	ListCell   *ctlist_item;
	int			nmembers;
	bool		ordered;
	HeapTuple	ntp;
	MemoryContext oldcxt;
	int			i;

	/*
	 * one-time startup overhead for each cache
	 */
	if (cache->cc_tupdesc == NULL)
		CatalogCacheInitializeCache(cache);

	Assert(nkeys > 0 && nkeys < cache->cc_nkeys);

#ifdef CATCACHE_STATS
	cache->cc_lsearches++;
#endif

	/*
	 * initialize the search key information
	 */
	memcpy(cur_skey, cache->cc_skey, sizeof(cur_skey));
	cur_skey[0].sk_argument = v1;
	cur_skey[1].sk_argument = v2;
	cur_skey[2].sk_argument = v3;
	cur_skey[3].sk_argument = v4;

	/*
	 * compute a hash value of the given keys for faster search.  We don't
	 * presently divide the CatCList items into buckets, but this still lets
	 * us skip non-matching items quickly most of the time.
	 */
	lHashValue = CatalogCacheComputeHashValue(cache, nkeys, cur_skey);

	/*
	 * scan the items until we find a match or exhaust our list
	 */
	for (elt = DLGetHead(&cache->cc_lists);
		 elt;
		 elt = DLGetSucc(elt))
	{
		bool		res;

		cl = (CatCList *) DLE_VAL(elt);

		if (cl->dead)
			continue;			/* ignore dead entries */

		if (cl->hash_value != lHashValue)
			continue;			/* quickly skip entry if wrong hash val */

		/*
		 * see if the cached list matches our key.
		 */
		if (cl->nkeys != nkeys)
			continue;
		HeapKeyTest(&cl->tuple,
					cache->cc_tupdesc,
					nkeys,
					cur_skey,
					res);
		if (!res)
			continue;

		/*
		 * We found a matching list.  Move the list to the front of the
		 * cache's list-of-lists, to speed subsequent searches.  (We do not
		 * move the members to the fronts of their hashbucket lists, however,
		 * since there's no point in that unless they are searched for
		 * individually.)
		 */
		DLMoveToFront(&cl->cache_elem);

		/* Bump the list's refcount and return it */
		ResourceOwnerEnlargeCatCacheListRefs(CurrentResourceOwner);
		cl->refcount++;
		ResourceOwnerRememberCatCacheListRef(CurrentResourceOwner, cl);

		CACHE2_elog(DEBUG2, "SearchCatCacheList(%s): found list",
					cache->cc_relname);

#ifdef CATCACHE_STATS
		cache->cc_lhits++;
#endif

		return cl;
	}

	/*
	 * List was not found in cache, so we have to build it by reading the
	 * relation.  For each matching tuple found in the relation, use an
	 * existing cache entry if possible, else build a new one.
	 *
	 * We have to bump the member refcounts temporarily to ensure they won't
	 * get dropped from the cache while loading other members. We use a PG_TRY
	 * block to ensure we can undo those refcounts if we get an error before
	 * we finish constructing the CatCList.
	 */
	ResourceOwnerEnlargeCatCacheListRefs(CurrentResourceOwner);

	ctlist = NIL;

	PG_TRY();
	{
		Relation	relation;
		SysScanDesc scandesc;

		relation = heap_open(cache->cc_reloid, AccessShareLock);

		scandesc = systable_beginscan(relation,
									  cache->cc_indexoid,
									  IndexScanOK(cache, cur_skey),
									  SnapshotNow,
									  nkeys,
									  cur_skey);

		/* The list will be ordered iff we are doing an index scan */
		ordered = (scandesc->irel != NULL);

		while (HeapTupleIsValid(ntp = systable_getnext(scandesc)))
		{
			uint32		hashValue;
			Index		hashIndex;

			/*
			 * See if there's an entry for this tuple already.
			 */
			ct = NULL;
			hashValue = CatalogCacheComputeTupleHashValue(cache, ntp);
			hashIndex = HASH_INDEX(hashValue, cache->cc_nbuckets);

			for (elt = DLGetHead(&cache->cc_bucket[hashIndex]);
				 elt;
				 elt = DLGetSucc(elt))
			{
				ct = (CatCTup *) DLE_VAL(elt);

				if (ct->dead || ct->negative)
					continue;	/* ignore dead and negative entries */

				if (ct->hash_value != hashValue)
					continue;	/* quickly skip entry if wrong hash val */

				if (!ItemPointerEquals(&(ct->tuple.t_self), &(ntp->t_self)))
					continue;	/* not same tuple */

				/*
				 * Found a match, but can't use it if it belongs to another
				 * list already
				 */
				if (ct->c_list)
					continue;

				break;			/* A-OK */
			}

			if (elt == NULL)
			{
				/* We didn't find a usable entry, so make a new one */
				ct = CatalogCacheCreateEntry(cache, ntp,
											 hashValue, hashIndex,
											 false);
			}

			/* Careful here: add entry to ctlist, then bump its refcount */
			/* This way leaves state correct if lappend runs out of memory */
			ctlist = lappend(ctlist, ct);
			ct->refcount++;
		}

		systable_endscan(scandesc);

		heap_close(relation, AccessShareLock);

		/*
		 * Now we can build the CatCList entry.  First we need a dummy tuple
		 * containing the key values...
		 */
		ntp = build_dummy_tuple(cache, nkeys, cur_skey);
		oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
		nmembers = list_length(ctlist);
		cl = (CatCList *)
			palloc(sizeof(CatCList) + nmembers * sizeof(CatCTup *));
		heap_copytuple_with_tuple(ntp, &cl->tuple);
		MemoryContextSwitchTo(oldcxt);
		heap_freetuple(ntp);

		/*
		 * We are now past the last thing that could trigger an elog before we
		 * have finished building the CatCList and remembering it in the
		 * resource owner.	So it's OK to fall out of the PG_TRY, and indeed
		 * we'd better do so before we start marking the members as belonging
		 * to the list.
		 */

	}
	PG_CATCH();
	{
		foreach(ctlist_item, ctlist)
		{
			ct = (CatCTup *) lfirst(ctlist_item);
			Assert(ct->c_list == NULL);
			Assert(ct->refcount > 0);
			ct->refcount--;
			if (
#ifndef CATCACHE_FORCE_RELEASE
				ct->dead &&
#endif
				ct->refcount == 0 &&
				(ct->c_list == NULL || ct->c_list->refcount == 0))
				CatCacheRemoveCTup(cache, ct);
		}

		PG_RE_THROW();
	}
Exemple #30
0
Datum
xpath_table(PG_FUNCTION_ARGS)
{
	/* Function parameters */
	char	   *pkeyfield = text_to_cstring(PG_GETARG_TEXT_PP(0));
	char	   *xmlfield = text_to_cstring(PG_GETARG_TEXT_PP(1));
	char	   *relname = text_to_cstring(PG_GETARG_TEXT_PP(2));
	char	   *xpathset = text_to_cstring(PG_GETARG_TEXT_PP(3));
	char	   *condition = text_to_cstring(PG_GETARG_TEXT_PP(4));

	/* SPI (input tuple) support */
	SPITupleTable *tuptable;
	HeapTuple	spi_tuple;
	TupleDesc	spi_tupdesc;

	/* Output tuple (tuplestore) support */
	Tuplestorestate *tupstore = NULL;
	TupleDesc	ret_tupdesc;
	HeapTuple	ret_tuple;

	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
	AttInMetadata *attinmeta;
	MemoryContext per_query_ctx;
	MemoryContext oldcontext;

	char	  **values;
	xmlChar   **xpaths;
	char	   *pos;
	const char *pathsep = "|";

	int			numpaths;
	int			ret;
	int			proc;
	int			i;
	int			j;
	int			rownr;			/* For issuing multiple rows from one original
								 * document */
	bool		had_values;		/* To determine end of nodeset results */
	StringInfoData query_buf;
	PgXmlErrorContext *xmlerrcxt;
	volatile xmlDocPtr doctree = NULL;

	/* We only have a valid tuple description in table function mode */
	if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("set-valued function called in context that cannot accept a set")));
	if (rsinfo->expectedDesc == NULL)
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
				 errmsg("xpath_table must be called as a table function")));

	/*
	 * We want to materialise because it means that we don't have to carry
	 * libxml2 parser state between invocations of this function
	 */
	if (!(rsinfo->allowedModes & SFRM_Materialize))
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
			   errmsg("xpath_table requires Materialize mode, but it is not "
					  "allowed in this context")));

	/*
	 * The tuplestore must exist in a higher context than this function call
	 * (per_query_ctx is used)
	 */
	per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
	oldcontext = MemoryContextSwitchTo(per_query_ctx);

	/*
	 * Create the tuplestore - work_mem is the max in-memory size before a
	 * file is created on disk to hold it.
	 */
	tupstore =
		tuplestore_begin_heap(rsinfo->allowedModes & SFRM_Materialize_Random,
							  false, work_mem);

	MemoryContextSwitchTo(oldcontext);

	/* get the requested return tuple description */
	ret_tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);

	/* must have at least one output column (for the pkey) */
	if (ret_tupdesc->natts < 1)
		ereport(ERROR,
				(errcode(ERRCODE_SYNTAX_ERROR),
				 errmsg("xpath_table must have at least one output column")));

	/*
	 * At the moment we assume that the returned attributes make sense for the
	 * XPath specififed (i.e. we trust the caller). It's not fatal if they get
	 * it wrong - the input function for the column type will raise an error
	 * if the path result can't be converted into the correct binary
	 * representation.
	 */

	attinmeta = TupleDescGetAttInMetadata(ret_tupdesc);

	/* Set return mode and allocate value space. */
	rsinfo->returnMode = SFRM_Materialize;
	rsinfo->setDesc = ret_tupdesc;

	values = (char **) palloc(ret_tupdesc->natts * sizeof(char *));
	xpaths = (xmlChar **) palloc(ret_tupdesc->natts * sizeof(xmlChar *));

	/*
	 * Split XPaths. xpathset is a writable CString.
	 *
	 * Note that we stop splitting once we've done all needed for tupdesc
	 */
	numpaths = 0;
	pos = xpathset;
	while (numpaths < (ret_tupdesc->natts - 1))
	{
		xpaths[numpaths++] = (xmlChar *) pos;
		pos = strstr(pos, pathsep);
		if (pos != NULL)
		{
			*pos = '\0';
			pos++;
		}
		else
			break;
	}

	/* Now build query */
	initStringInfo(&query_buf);

	/* Build initial sql statement */
	appendStringInfo(&query_buf, "SELECT %s, %s FROM %s WHERE %s",
					 pkeyfield,
					 xmlfield,
					 relname,
					 condition);

	if ((ret = SPI_connect()) < 0)
		elog(ERROR, "xpath_table: SPI_connect returned %d", ret);

	if ((ret = SPI_exec(query_buf.data, 0)) != SPI_OK_SELECT)
		elog(ERROR, "xpath_table: SPI execution failed for query %s",
			 query_buf.data);

	proc = SPI_processed;
	/* elog(DEBUG1,"xpath_table: SPI returned %d rows",proc); */
	tuptable = SPI_tuptable;
	spi_tupdesc = tuptable->tupdesc;

	/* Switch out of SPI context */
	MemoryContextSwitchTo(oldcontext);

	/*
	 * Check that SPI returned correct result. If you put a comma into one of
	 * the function parameters, this will catch it when the SPI query returns
	 * e.g. 3 columns.
	 */
	if (spi_tupdesc->natts != 2)
	{
		ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
						errmsg("expression returning multiple columns is not valid in parameter list"),
						errdetail("Expected two columns in SPI result, got %d.", spi_tupdesc->natts)));
	}

	/*
	 * Setup the parser.  This should happen after we are done evaluating the
	 * query, in case it calls functions that set up libxml differently.
	 */
	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);

	PG_TRY();
	{
		/* For each row i.e. document returned from SPI */
		for (i = 0; i < proc; i++)
		{
			char	   *pkey;
			char	   *xmldoc;
			xmlXPathContextPtr ctxt;
			xmlXPathObjectPtr res;
			xmlChar    *resstr;
			xmlXPathCompExprPtr comppath;

			/* Extract the row data as C Strings */
			spi_tuple = tuptable->vals[i];
			pkey = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
			xmldoc = SPI_getvalue(spi_tuple, spi_tupdesc, 2);

			/*
			 * Clear the values array, so that not-well-formed documents
			 * return NULL in all columns.	Note that this also means that
			 * spare columns will be NULL.
			 */
			for (j = 0; j < ret_tupdesc->natts; j++)
				values[j] = NULL;

			/* Insert primary key */
			values[0] = pkey;

			/* Parse the document */
			if (xmldoc)
				doctree = xmlParseMemory(xmldoc, strlen(xmldoc));
			else	/* treat NULL as not well-formed */
				doctree = NULL;

			if (doctree == NULL)
			{
				/* not well-formed, so output all-NULL tuple */
				ret_tuple = BuildTupleFromCStrings(attinmeta, values);
				tuplestore_puttuple(tupstore, ret_tuple);
				heap_freetuple(ret_tuple);
			}
			else
			{
				/* New loop here - we have to deal with nodeset results */
				rownr = 0;

				do
				{
					/* Now evaluate the set of xpaths. */
					had_values = false;
					for (j = 0; j < numpaths; j++)
					{
						ctxt = xmlXPathNewContext(doctree);
						ctxt->node = xmlDocGetRootElement(doctree);

						/* compile the path */
						comppath = xmlXPathCompile(xpaths[j]);
						if (comppath == NULL)
							xml_ereport(xmlerrcxt, ERROR,
										ERRCODE_EXTERNAL_ROUTINE_EXCEPTION,
										"XPath Syntax Error");

						/* Now evaluate the path expression. */
						res = xmlXPathCompiledEval(comppath, ctxt);
						xmlXPathFreeCompExpr(comppath);

						if (res != NULL)
						{
							switch (res->type)
							{
								case XPATH_NODESET:
									/* We see if this nodeset has enough nodes */
									if (res->nodesetval != NULL &&
										rownr < res->nodesetval->nodeNr)
									{
										resstr = xmlXPathCastNodeToString(res->nodesetval->nodeTab[rownr]);
										had_values = true;
									}
									else
										resstr = NULL;

									break;

								case XPATH_STRING:
									resstr = xmlStrdup(res->stringval);
									break;

								default:
									elog(NOTICE, "unsupported XQuery result: %d", res->type);
									resstr = xmlStrdup((const xmlChar *) "<unsupported/>");
							}

							/*
							 * Insert this into the appropriate column in the
							 * result tuple.
							 */
							values[j + 1] = (char *) resstr;
						}
						xmlXPathFreeContext(ctxt);
					}

					/* Now add the tuple to the output, if there is one. */
					if (had_values)
					{
						ret_tuple = BuildTupleFromCStrings(attinmeta, values);
						tuplestore_puttuple(tupstore, ret_tuple);
						heap_freetuple(ret_tuple);
					}

					rownr++;
				} while (had_values);
			}

			if (doctree != NULL)
				xmlFreeDoc(doctree);
			doctree = NULL;

			if (pkey)
				pfree(pkey);
			if (xmldoc)
				pfree(xmldoc);
		}
	}
	PG_CATCH();
	{
		if (doctree != NULL)
			xmlFreeDoc(doctree);

		pg_xml_done(xmlerrcxt, true);

		PG_RE_THROW();
	}
	PG_END_TRY();

	if (doctree != NULL)
		xmlFreeDoc(doctree);

	pg_xml_done(xmlerrcxt, false);

	tuplestore_donestoring(tupstore);

	SPI_finish();

	rsinfo->setResult = tupstore;

	/*
	 * SFRM_Materialize mode expects us to return a NULL Datum. The actual
	 * tuples are in our tuplestore and passed back through rsinfo->setResult.
	 * rsinfo->setDesc is set to the tuple description that we actually used
	 * to build our tuples with, so the caller can verify we did what it was
	 * expecting.
	 */
	return (Datum) 0;
}