Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2182 insertions, 0 deletions

diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
new file mode 100644
index 0000000..356aac4
--- /dev/null
+++ b/src/backend/commands/event_trigger.c
@@ -0,0 +1,2182 @@
+/*-------------------------------------------------------------------------
+ *
+ * event_trigger.c
+ *	  PostgreSQL EVENT TRIGGER support code.
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *	  src/backend/commands/event_trigger.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/htup_details.h"
+#include "access/table.h"
+#include "access/xact.h"
+#include "catalog/catalog.h"
+#include "catalog/dependency.h"
+#include "catalog/indexing.h"
+#include "catalog/objectaccess.h"
+#include "catalog/pg_event_trigger.h"
+#include "catalog/pg_namespace.h"
+#include "catalog/pg_opclass.h"
+#include "catalog/pg_opfamily.h"
+#include "catalog/pg_proc.h"
+#include "catalog/pg_trigger.h"
+#include "catalog/pg_ts_config.h"
+#include "catalog/pg_type.h"
+#include "commands/dbcommands.h"
+#include "commands/event_trigger.h"
+#include "commands/extension.h"
+#include "commands/trigger.h"
+#include "funcapi.h"
+#include "lib/ilist.h"
+#include "miscadmin.h"
+#include "parser/parse_func.h"
+#include "pgstat.h"
+#include "tcop/deparse_utility.h"
+#include "tcop/utility.h"
+#include "utils/acl.h"
+#include "utils/builtins.h"
+#include "utils/evtcache.h"
+#include "utils/fmgroids.h"
+#include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/rel.h"
+#include "utils/syscache.h"
+
+typedef struct EventTriggerQueryState
+{
+	/* memory context for this state's objects */
+	MemoryContext cxt;
+
+	/* sql_drop */
+	slist_head	SQLDropList;
+	bool		in_sql_drop;
+
+	/* table_rewrite */
+	Oid			table_rewrite_oid;	/* InvalidOid, or set for table_rewrite
+									 * event */
+	int			table_rewrite_reason;	/* AT_REWRITE reason */
+
+	/* Support for command collection */
+	bool		commandCollectionInhibited;
+	CollectedCommand *currentCommand;
+	List	   *commandList;	/* list of CollectedCommand; see
+								 * deparse_utility.h */
+	struct EventTriggerQueryState *previous;
+} EventTriggerQueryState;
+
+static EventTriggerQueryState *currentEventTriggerState = NULL;
+
+/* Support for dropped objects */
+typedef struct SQLDropObject
+{
+	ObjectAddress address;
+	const char *schemaname;
+	const char *objname;
+	const char *objidentity;
+	const char *objecttype;
+	List	   *addrnames;
+	List	   *addrargs;
+	bool		original;
+	bool		normal;
+	bool		istemp;
+	slist_node	next;
+} SQLDropObject;
+
+static void AlterEventTriggerOwner_internal(Relation rel,
+											HeapTuple tup,
+											Oid newOwnerId);
+static void error_duplicate_filter_variable(const char *defname);
+static Datum filter_list_to_array(List *filterlist);
+static Oid	insert_event_trigger_tuple(const char *trigname, const char *eventname,
+									   Oid evtOwner, Oid funcoid, List *tags);
+static void validate_ddl_tags(const char *filtervar, List *taglist);
+static void validate_table_rewrite_tags(const char *filtervar, List *taglist);
+static void EventTriggerInvoke(List *fn_oid_list, EventTriggerData *trigdata);
+static const char *stringify_grant_objtype(ObjectType objtype);
+static const char *stringify_adefprivs_objtype(ObjectType objtype);
+
+/*
+ * Create an event trigger.
+ */
+Oid
+CreateEventTrigger(CreateEventTrigStmt *stmt)
+{
+	HeapTuple	tuple;
+	Oid			funcoid;
+	Oid			funcrettype;
+	Oid			evtowner = GetUserId();
+	ListCell   *lc;
+	List	   *tags = NULL;
+
+	/*
+	 * It would be nice to allow database owners or even regular users to do
+	 * this, but there are obvious privilege escalation risks which would have
+	 * to somehow be plugged first.
+	 */
+	if (!superuser())
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+				 errmsg("permission denied to create event trigger \"%s\"",
+						stmt->trigname),
+				 errhint("Must be superuser to create an event trigger.")));
+
+	/* Validate event name. */
+	if (strcmp(stmt->eventname, "ddl_command_start") != 0 &&
+		strcmp(stmt->eventname, "ddl_command_end") != 0 &&
+		strcmp(stmt->eventname, "sql_drop") != 0 &&
+		strcmp(stmt->eventname, "table_rewrite") != 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_SYNTAX_ERROR),
+				 errmsg("unrecognized event name \"%s\"",
+						stmt->eventname)));
+
+	/* Validate filter conditions. */
+	foreach(lc, stmt->whenclause)
+	{
+		DefElem    *def = (DefElem *) lfirst(lc);
+
+		if (strcmp(def->defname, "tag") == 0)
+		{
+			if (tags != NULL)
+				error_duplicate_filter_variable(def->defname);
+			tags = (List *) def->arg;
+		}
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_SYNTAX_ERROR),
+					 errmsg("unrecognized filter variable \"%s\"", def->defname)));
+	}
+
+	/* Validate tag list, if any. */
+	if ((strcmp(stmt->eventname, "ddl_command_start") == 0 ||
+		 strcmp(stmt->eventname, "ddl_command_end") == 0 ||
+		 strcmp(stmt->eventname, "sql_drop") == 0)
+		&& tags != NULL)
+		validate_ddl_tags("tag", tags);
+	else if (strcmp(stmt->eventname, "table_rewrite") == 0
+			 && tags != NULL)
+		validate_table_rewrite_tags("tag", tags);
+
+	/*
+	 * Give user a nice error message if an event trigger of the same name
+	 * already exists.
+	 */
+	tuple = SearchSysCache1(EVENTTRIGGERNAME, CStringGetDatum(stmt->trigname));
+	if (HeapTupleIsValid(tuple))
+		ereport(ERROR,
+				(errcode(ERRCODE_DUPLICATE_OBJECT),
+				 errmsg("event trigger \"%s\" already exists",
+						stmt->trigname)));
+
+	/* Find and validate the trigger function. */
+	funcoid = LookupFuncName(stmt->funcname, 0, NULL, false);
+	funcrettype = get_func_rettype(funcoid);
+	if (funcrettype != EVENT_TRIGGEROID)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("function %s must return type %s",
+						NameListToString(stmt->funcname), "event_trigger")));
+
+	/* Insert catalog entries. */
+	return insert_event_trigger_tuple(stmt->trigname, stmt->eventname,
+									  evtowner, funcoid, tags);
+}
+
+/*
+ * Validate DDL command tags.
+ */
+static void
+validate_ddl_tags(const char *filtervar, List *taglist)
+{
+	ListCell   *lc;
+
+	foreach(lc, taglist)
+	{
+		const char *tagstr = strVal(lfirst(lc));
+		CommandTag	commandTag = GetCommandTagEnum(tagstr);
+
+		if (commandTag == CMDTAG_UNKNOWN)
+			ereport(ERROR,
+					(errcode(ERRCODE_SYNTAX_ERROR),
+					 errmsg("filter value \"%s\" not recognized for filter variable \"%s\"",
+							tagstr, filtervar)));
+		if (!command_tag_event_trigger_ok(commandTag))
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+			/* translator: %s represents an SQL statement name */
+					 errmsg("event triggers are not supported for %s",
+							tagstr)));
+	}
+}
+
+/*
+ * Validate DDL command tags for event table_rewrite.
+ */
+static void
+validate_table_rewrite_tags(const char *filtervar, List *taglist)
+{
+	ListCell   *lc;
+
+	foreach(lc, taglist)
+	{
+		const char *tagstr = strVal(lfirst(lc));
+		CommandTag	commandTag = GetCommandTagEnum(tagstr);
+
+		if (!command_tag_table_rewrite_ok(commandTag))
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+			/* translator: %s represents an SQL statement name */
+					 errmsg("event triggers are not supported for %s",
+							tagstr)));
+	}
+}
+
+/*
+ * Complain about a duplicate filter variable.
+ */
+static void
+error_duplicate_filter_variable(const char *defname)
+{
+	ereport(ERROR,
+			(errcode(ERRCODE_SYNTAX_ERROR),
+			 errmsg("filter variable \"%s\" specified more than once",
+					defname)));
+}
+
+/*
+ * Insert the new pg_event_trigger row and record dependencies.
+ */
+static Oid
+insert_event_trigger_tuple(const char *trigname, const char *eventname, Oid evtOwner,
+						   Oid funcoid, List *taglist)
+{
+	Relation	tgrel;
+	Oid			trigoid;
+	HeapTuple	tuple;
+	Datum		values[Natts_pg_trigger];
+	bool		nulls[Natts_pg_trigger];
+	NameData	evtnamedata,
+				evteventdata;
+	ObjectAddress myself,
+				referenced;
+
+	/* Open pg_event_trigger. */
+	tgrel = table_open(EventTriggerRelationId, RowExclusiveLock);
+
+	/* Build the new pg_trigger tuple. */
+	trigoid = GetNewOidWithIndex(tgrel, EventTriggerOidIndexId,
+								 Anum_pg_event_trigger_oid);
+	values[Anum_pg_event_trigger_oid - 1] = ObjectIdGetDatum(trigoid);
+	memset(nulls, false, sizeof(nulls));
+	namestrcpy(&evtnamedata, trigname);
+	values[Anum_pg_event_trigger_evtname - 1] = NameGetDatum(&evtnamedata);
+	namestrcpy(&evteventdata, eventname);
+	values[Anum_pg_event_trigger_evtevent - 1] = NameGetDatum(&evteventdata);
+	values[Anum_pg_event_trigger_evtowner - 1] = ObjectIdGetDatum(evtOwner);
+	values[Anum_pg_event_trigger_evtfoid - 1] = ObjectIdGetDatum(funcoid);
+	values[Anum_pg_event_trigger_evtenabled - 1] =
+		CharGetDatum(TRIGGER_FIRES_ON_ORIGIN);
+	if (taglist == NIL)
+		nulls[Anum_pg_event_trigger_evttags - 1] = true;
+	else
+		values[Anum_pg_event_trigger_evttags - 1] =
+			filter_list_to_array(taglist);
+
+	/* Insert heap tuple. */
+	tuple = heap_form_tuple(tgrel->rd_att, values, nulls);
+	CatalogTupleInsert(tgrel, tuple);
+	heap_freetuple(tuple);
+
+	/* Depend on owner. */
+	recordDependencyOnOwner(EventTriggerRelationId, trigoid, evtOwner);
+
+	/* Depend on event trigger function. */
+	myself.classId = EventTriggerRelationId;
+	myself.objectId = trigoid;
+	myself.objectSubId = 0;
+	referenced.classId = ProcedureRelationId;
+	referenced.objectId = funcoid;
+	referenced.objectSubId = 0;
+	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
+
+	/* Depend on extension, if any. */
+	recordDependencyOnCurrentExtension(&myself, false);
+
+	/* Post creation hook for new event trigger */
+	InvokeObjectPostCreateHook(EventTriggerRelationId, trigoid, 0);
+
+	/* Close pg_event_trigger. */
+	table_close(tgrel, RowExclusiveLock);
+
+	return trigoid;
+}
+
+/*
+ * In the parser, a clause like WHEN tag IN ('cmd1', 'cmd2') is represented
+ * by a DefElem whose value is a List of String nodes; in the catalog, we
+ * store the list of strings as a text array.  This function transforms the
+ * former representation into the latter one.
+ *
+ * For cleanliness, we store command tags in the catalog as text.  It's
+ * possible (although not currently anticipated) that we might have
+ * a case-sensitive filter variable in the future, in which case this would
+ * need some further adjustment.
+ */
+static Datum
+filter_list_to_array(List *filterlist)
+{
+	ListCell   *lc;
+	Datum	   *data;
+	int			i = 0,
+				l = list_length(filterlist);
+
+	data = (Datum *) palloc(l * sizeof(Datum));
+
+	foreach(lc, filterlist)
+	{
+		const char *value = strVal(lfirst(lc));
+		char	   *result,
+				   *p;
+
+		result = pstrdup(value);
+		for (p = result; *p; p++)
+			*p = pg_ascii_toupper((unsigned char) *p);
+		data[i++] = PointerGetDatum(cstring_to_text(result));
+		pfree(result);
+	}
+
+	return PointerGetDatum(construct_array(data, l, TEXTOID,
+										   -1, false, TYPALIGN_INT));
+}
+
+/*
+ * ALTER EVENT TRIGGER foo ENABLE|DISABLE|ENABLE ALWAYS|REPLICA
+ */
+Oid
+AlterEventTrigger(AlterEventTrigStmt *stmt)
+{
+	Relation	tgrel;
+	HeapTuple	tup;
+	Oid			trigoid;
+	Form_pg_event_trigger evtForm;
+	char		tgenabled = stmt->tgenabled;
+
+	tgrel = table_open(EventTriggerRelationId, RowExclusiveLock);
+
+	tup = SearchSysCacheCopy1(EVENTTRIGGERNAME,
+							  CStringGetDatum(stmt->trigname));
+	if (!HeapTupleIsValid(tup))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("event trigger \"%s\" does not exist",
+						stmt->trigname)));
+
+	evtForm = (Form_pg_event_trigger) GETSTRUCT(tup);
+	trigoid = evtForm->oid;
+
+	if (!pg_event_trigger_ownercheck(trigoid, GetUserId()))
+		aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_EVENT_TRIGGER,
+					   stmt->trigname);
+
+	/* tuple is a copy, so we can modify it below */
+	evtForm->evtenabled = tgenabled;
+
+	CatalogTupleUpdate(tgrel, &tup->t_self, tup);
+
+	InvokeObjectPostAlterHook(EventTriggerRelationId,
+							  trigoid, 0);
+
+	/* clean up */
+	heap_freetuple(tup);
+	table_close(tgrel, RowExclusiveLock);
+
+	return trigoid;
+}
+
+/*
+ * Change event trigger's owner -- by name
+ */
+ObjectAddress
+AlterEventTriggerOwner(const char *name, Oid newOwnerId)
+{
+	Oid			evtOid;
+	HeapTuple	tup;
+	Form_pg_event_trigger evtForm;
+	Relation	rel;
+	ObjectAddress address;
+
+	rel = table_open(EventTriggerRelationId, RowExclusiveLock);
+
+	tup = SearchSysCacheCopy1(EVENTTRIGGERNAME, CStringGetDatum(name));
+
+	if (!HeapTupleIsValid(tup))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("event trigger \"%s\" does not exist", name)));
+
+	evtForm = (Form_pg_event_trigger) GETSTRUCT(tup);
+	evtOid = evtForm->oid;
+
+	AlterEventTriggerOwner_internal(rel, tup, newOwnerId);
+
+	ObjectAddressSet(address, EventTriggerRelationId, evtOid);
+
+	heap_freetuple(tup);
+
+	table_close(rel, RowExclusiveLock);
+
+	return address;
+}
+
+/*
+ * Change event trigger owner, by OID
+ */
+void
+AlterEventTriggerOwner_oid(Oid trigOid, Oid newOwnerId)
+{
+	HeapTuple	tup;
+	Relation	rel;
+
+	rel = table_open(EventTriggerRelationId, RowExclusiveLock);
+
+	tup = SearchSysCacheCopy1(EVENTTRIGGEROID, ObjectIdGetDatum(trigOid));
+
+	if (!HeapTupleIsValid(tup))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("event trigger with OID %u does not exist", trigOid)));
+
+	AlterEventTriggerOwner_internal(rel, tup, newOwnerId);
+
+	heap_freetuple(tup);
+
+	table_close(rel, RowExclusiveLock);
+}
+
+/*
+ * Internal workhorse for changing an event trigger's owner
+ */
+static void
+AlterEventTriggerOwner_internal(Relation rel, HeapTuple tup, Oid newOwnerId)
+{
+	Form_pg_event_trigger form;
+
+	form = (Form_pg_event_trigger) GETSTRUCT(tup);
+
+	if (form->evtowner == newOwnerId)
+		return;
+
+	if (!pg_event_trigger_ownercheck(form->oid, GetUserId()))
+		aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_EVENT_TRIGGER,
+					   NameStr(form->evtname));
+
+	/* New owner must be a superuser */
+	if (!superuser_arg(newOwnerId))
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+				 errmsg("permission denied to change owner of event trigger \"%s\"",
+						NameStr(form->evtname)),
+				 errhint("The owner of an event trigger must be a superuser.")));
+
+	form->evtowner = newOwnerId;
+	CatalogTupleUpdate(rel, &tup->t_self, tup);
+
+	/* Update owner dependency reference */
+	changeDependencyOnOwner(EventTriggerRelationId,
+							form->oid,
+							newOwnerId);
+
+	InvokeObjectPostAlterHook(EventTriggerRelationId,
+							  form->oid, 0);
+}
+
+/*
+ * get_event_trigger_oid - Look up an event trigger by name to find its OID.
+ *
+ * If missing_ok is false, throw an error if trigger not found.  If
+ * true, just return InvalidOid.
+ */
+Oid
+get_event_trigger_oid(const char *trigname, bool missing_ok)
+{
+	Oid			oid;
+
+	oid = GetSysCacheOid1(EVENTTRIGGERNAME, Anum_pg_event_trigger_oid,
+						  CStringGetDatum(trigname));
+	if (!OidIsValid(oid) && !missing_ok)
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("event trigger \"%s\" does not exist", trigname)));
+	return oid;
+}
+
+/*
+ * Return true when we want to fire given Event Trigger and false otherwise,
+ * filtering on the session replication role and the event trigger registered
+ * tags matching.
+ */
+static bool
+filter_event_trigger(CommandTag tag, EventTriggerCacheItem *item)
+{
+	/*
+	 * Filter by session replication role, knowing that we never see disabled
+	 * items down here.
+	 */
+	if (SessionReplicationRole == SESSION_REPLICATION_ROLE_REPLICA)
+	{
+		if (item->enabled == TRIGGER_FIRES_ON_ORIGIN)
+			return false;
+	}
+	else
+	{
+		if (item->enabled == TRIGGER_FIRES_ON_REPLICA)
+			return false;
+	}
+
+	/* Filter by tags, if any were specified. */
+	if (!bms_is_empty(item->tagset) && !bms_is_member(tag, item->tagset))
+		return false;
+
+	/* if we reach that point, we're not filtering out this item */
+	return true;
+}
+
+/*
+ * Setup for running triggers for the given event.  Return value is an OID list
+ * of functions to run; if there are any, trigdata is filled with an
+ * appropriate EventTriggerData for them to receive.
+ */
+static List *
+EventTriggerCommonSetup(Node *parsetree,
+						EventTriggerEvent event, const char *eventstr,
+						EventTriggerData *trigdata)
+{
+	CommandTag	tag;
+	List	   *cachelist;
+	ListCell   *lc;
+	List	   *runlist = NIL;
+
+	/*
+	 * We want the list of command tags for which this procedure is actually
+	 * invoked to match up exactly with the list that CREATE EVENT TRIGGER
+	 * accepts.  This debugging cross-check will throw an error if this
+	 * function is invoked for a command tag that CREATE EVENT TRIGGER won't
+	 * accept.  (Unfortunately, there doesn't seem to be any simple, automated
+	 * way to verify that CREATE EVENT TRIGGER doesn't accept extra stuff that
+	 * never reaches this control point.)
+	 *
+	 * If this cross-check fails for you, you probably need to either adjust
+	 * standard_ProcessUtility() not to invoke event triggers for the command
+	 * type in question, or you need to adjust event_trigger_ok to accept the
+	 * relevant command tag.
+	 */
+#ifdef USE_ASSERT_CHECKING
+	{
+		CommandTag	dbgtag;
+
+		dbgtag = CreateCommandTag(parsetree);
+		if (event == EVT_DDLCommandStart ||
+			event == EVT_DDLCommandEnd ||
+			event == EVT_SQLDrop)
+		{
+			if (!command_tag_event_trigger_ok(dbgtag))
+				elog(ERROR, "unexpected command tag \"%s\"", GetCommandTagName(dbgtag));
+		}
+		else if (event == EVT_TableRewrite)
+		{
+			if (!command_tag_table_rewrite_ok(dbgtag))
+				elog(ERROR, "unexpected command tag \"%s\"", GetCommandTagName(dbgtag));
+		}
+	}
+#endif
+
+	/* Use cache to find triggers for this event; fast exit if none. */
+	cachelist = EventCacheLookup(event);
+	if (cachelist == NIL)
+		return NIL;
+
+	/* Get the command tag. */
+	tag = CreateCommandTag(parsetree);
+
+	/*
+	 * Filter list of event triggers by command tag, and copy them into our
+	 * memory context.  Once we start running the command triggers, or indeed
+	 * once we do anything at all that touches the catalogs, an invalidation
+	 * might leave cachelist pointing at garbage, so we must do this before we
+	 * can do much else.
+	 */
+	foreach(lc, cachelist)
+	{
+		EventTriggerCacheItem *item = lfirst(lc);
+
+		if (filter_event_trigger(tag, item))
+		{
+			/* We must plan to fire this trigger. */
+			runlist = lappend_oid(runlist, item->fnoid);
+		}
+	}
+
+	/* don't spend any more time on this if no functions to run */
+	if (runlist == NIL)
+		return NIL;
+
+	trigdata->type = T_EventTriggerData;
+	trigdata->event = eventstr;
+	trigdata->parsetree = parsetree;
+	trigdata->tag = tag;
+
+	return runlist;
+}
+
+/*
+ * Fire ddl_command_start triggers.
+ */
+void
+EventTriggerDDLCommandStart(Node *parsetree)
+{
+	List	   *runlist;
+	EventTriggerData trigdata;
+
+	/*
+	 * Event Triggers are completely disabled in standalone mode.  There are
+	 * (at least) two reasons for this:
+	 *
+	 * 1. A sufficiently broken event trigger might not only render the
+	 * database unusable, but prevent disabling itself to fix the situation.
+	 * In this scenario, restarting in standalone mode provides an escape
+	 * hatch.
+	 *
+	 * 2. BuildEventTriggerCache relies on systable_beginscan_ordered, and
+	 * therefore will malfunction if pg_event_trigger's indexes are damaged.
+	 * To allow recovery from a damaged index, we need some operating mode
+	 * wherein event triggers are disabled.  (Or we could implement
+	 * heapscan-and-sort logic for that case, but having disaster recovery
+	 * scenarios depend on code that's otherwise untested isn't appetizing.)
+	 */
+	if (!IsUnderPostmaster)
+		return;
+
+	runlist = EventTriggerCommonSetup(parsetree,
+									  EVT_DDLCommandStart,
+									  "ddl_command_start",
+									  &trigdata);
+	if (runlist == NIL)
+		return;
+
+	/* Run the triggers. */
+	EventTriggerInvoke(runlist, &trigdata);
+
+	/* Cleanup. */
+	list_free(runlist);
+
+	/*
+	 * Make sure anything the event triggers did will be visible to the main
+	 * command.
+	 */
+	CommandCounterIncrement();
+}
+
+/*
+ * Fire ddl_command_end triggers.
+ */
+void
+EventTriggerDDLCommandEnd(Node *parsetree)
+{
+	List	   *runlist;
+	EventTriggerData trigdata;
+
+	/*
+	 * See EventTriggerDDLCommandStart for a discussion about why event
+	 * triggers are disabled in single user mode.
+	 */
+	if (!IsUnderPostmaster)
+		return;
+
+	/*
+	 * Also do nothing if our state isn't set up, which it won't be if there
+	 * weren't any relevant event triggers at the start of the current DDL
+	 * command.  This test might therefore seem optional, but it's important
+	 * because EventTriggerCommonSetup might find triggers that didn't exist
+	 * at the time the command started.  Although this function itself
+	 * wouldn't crash, the event trigger functions would presumably call
+	 * pg_event_trigger_ddl_commands which would fail.  Better to do nothing
+	 * until the next command.
+	 */
+	if (!currentEventTriggerState)
+		return;
+
+	runlist = EventTriggerCommonSetup(parsetree,
+									  EVT_DDLCommandEnd, "ddl_command_end",
+									  &trigdata);
+	if (runlist == NIL)
+		return;
+
+	/*
+	 * Make sure anything the main command did will be visible to the event
+	 * triggers.
+	 */
+	CommandCounterIncrement();
+
+	/* Run the triggers. */
+	EventTriggerInvoke(runlist, &trigdata);
+
+	/* Cleanup. */
+	list_free(runlist);
+}
+
+/*
+ * Fire sql_drop triggers.
+ */
+void
+EventTriggerSQLDrop(Node *parsetree)
+{
+	List	   *runlist;
+	EventTriggerData trigdata;
+
+	/*
+	 * See EventTriggerDDLCommandStart for a discussion about why event
+	 * triggers are disabled in single user mode.
+	 */
+	if (!IsUnderPostmaster)
+		return;
+
+	/*
+	 * Use current state to determine whether this event fires at all.  If
+	 * there are no triggers for the sql_drop event, then we don't have
+	 * anything to do here.  Note that dropped object collection is disabled
+	 * if this is the case, so even if we were to try to run, the list would
+	 * be empty.
+	 */
+	if (!currentEventTriggerState ||
+		slist_is_empty(&currentEventTriggerState->SQLDropList))
+		return;
+
+	runlist = EventTriggerCommonSetup(parsetree,
+									  EVT_SQLDrop, "sql_drop",
+									  &trigdata);
+
+	/*
+	 * Nothing to do if run list is empty.  Note this typically can't happen,
+	 * because if there are no sql_drop events, then objects-to-drop wouldn't
+	 * have been collected in the first place and we would have quit above.
+	 * But it could occur if event triggers were dropped partway through.
+	 */
+	if (runlist == NIL)
+		return;
+
+	/*
+	 * Make sure anything the main command did will be visible to the event
+	 * triggers.
+	 */
+	CommandCounterIncrement();
+
+	/*
+	 * Make sure pg_event_trigger_dropped_objects only works when running
+	 * these triggers.  Use PG_TRY to ensure in_sql_drop is reset even when
+	 * one trigger fails.  (This is perhaps not necessary, as the currentState
+	 * variable will be removed shortly by our caller, but it seems better to
+	 * play safe.)
+	 */
+	currentEventTriggerState->in_sql_drop = true;
+
+	/* Run the triggers. */
+	PG_TRY();
+	{
+		EventTriggerInvoke(runlist, &trigdata);
+	}
+	PG_FINALLY();
+	{
+		currentEventTriggerState->in_sql_drop = false;
+	}
+	PG_END_TRY();
+
+	/* Cleanup. */
+	list_free(runlist);
+}
+
+
+/*
+ * Fire table_rewrite triggers.
+ */
+void
+EventTriggerTableRewrite(Node *parsetree, Oid tableOid, int reason)
+{
+	List	   *runlist;
+	EventTriggerData trigdata;
+
+	/*
+	 * See EventTriggerDDLCommandStart for a discussion about why event
+	 * triggers are disabled in single user mode.
+	 */
+	if (!IsUnderPostmaster)
+		return;
+
+	/*
+	 * Also do nothing if our state isn't set up, which it won't be if there
+	 * weren't any relevant event triggers at the start of the current DDL
+	 * command.  This test might therefore seem optional, but it's
+	 * *necessary*, because EventTriggerCommonSetup might find triggers that
+	 * didn't exist at the time the command started.
+	 */
+	if (!currentEventTriggerState)
+		return;
+
+	runlist = EventTriggerCommonSetup(parsetree,
+									  EVT_TableRewrite,
+									  "table_rewrite",
+									  &trigdata);
+	if (runlist == NIL)
+		return;
+
+	/*
+	 * Make sure pg_event_trigger_table_rewrite_oid only works when running
+	 * these triggers. Use PG_TRY to ensure table_rewrite_oid is reset even
+	 * when one trigger fails. (This is perhaps not necessary, as the
+	 * currentState variable will be removed shortly by our caller, but it
+	 * seems better to play safe.)
+	 */
+	currentEventTriggerState->table_rewrite_oid = tableOid;
+	currentEventTriggerState->table_rewrite_reason = reason;
+
+	/* Run the triggers. */
+	PG_TRY();
+	{
+		EventTriggerInvoke(runlist, &trigdata);
+	}
+	PG_FINALLY();
+	{
+		currentEventTriggerState->table_rewrite_oid = InvalidOid;
+		currentEventTriggerState->table_rewrite_reason = 0;
+	}
+	PG_END_TRY();
+
+	/* Cleanup. */
+	list_free(runlist);
+
+	/*
+	 * Make sure anything the event triggers did will be visible to the main
+	 * command.
+	 */
+	CommandCounterIncrement();
+}
+
+/*
+ * Invoke each event trigger in a list of event triggers.
+ */
+static void
+EventTriggerInvoke(List *fn_oid_list, EventTriggerData *trigdata)
+{
+	MemoryContext context;
+	MemoryContext oldcontext;
+	ListCell   *lc;
+	bool		first = true;
+
+	/* Guard against stack overflow due to recursive event trigger */
+	check_stack_depth();
+
+	/*
+	 * Let's evaluate event triggers in their own memory context, so that any
+	 * leaks get cleaned up promptly.
+	 */
+	context = AllocSetContextCreate(CurrentMemoryContext,
+									"event trigger context",
+									ALLOCSET_DEFAULT_SIZES);
+	oldcontext = MemoryContextSwitchTo(context);
+
+	/* Call each event trigger. */
+	foreach(lc, fn_oid_list)
+	{
+		LOCAL_FCINFO(fcinfo, 0);
+		Oid			fnoid = lfirst_oid(lc);
+		FmgrInfo	flinfo;
+		PgStat_FunctionCallUsage fcusage;
+
+		elog(DEBUG1, "EventTriggerInvoke %u", fnoid);
+
+		/*
+		 * We want each event trigger to be able to see the results of the
+		 * previous event trigger's action.  Caller is responsible for any
+		 * command-counter increment that is needed between the event trigger
+		 * and anything else in the transaction.
+		 */
+		if (first)
+			first = false;
+		else
+			CommandCounterIncrement();
+
+		/* Look up the function */
+		fmgr_info(fnoid, &flinfo);
+
+		/* Call the function, passing no arguments but setting a context. */
+		InitFunctionCallInfoData(*fcinfo, &flinfo, 0,
+								 InvalidOid, (Node *) trigdata, NULL);
+		pgstat_init_function_usage(fcinfo, &fcusage);
+		FunctionCallInvoke(fcinfo);
+		pgstat_end_function_usage(&fcusage, true);
+
+		/* Reclaim memory. */
+		MemoryContextReset(context);
+	}
+
+	/* Restore old memory context and delete the temporary one. */
+	MemoryContextSwitchTo(oldcontext);
+	MemoryContextDelete(context);
+}
+
+/*
+ * Do event triggers support this object type?
+ */
+bool
+EventTriggerSupportsObjectType(ObjectType obtype)
+{
+	switch (obtype)
+	{
+		case OBJECT_DATABASE:
+		case OBJECT_TABLESPACE:
+		case OBJECT_ROLE:
+		case OBJECT_PARAMETER_ACL:
+			/* no support for global objects */
+			return false;
+		case OBJECT_EVENT_TRIGGER:
+			/* no support for event triggers on event triggers */
+			return false;
+		case OBJECT_ACCESS_METHOD:
+		case OBJECT_AGGREGATE:
+		case OBJECT_AMOP:
+		case OBJECT_AMPROC:
+		case OBJECT_ATTRIBUTE:
+		case OBJECT_CAST:
+		case OBJECT_COLUMN:
+		case OBJECT_COLLATION:
+		case OBJECT_CONVERSION:
+		case OBJECT_DEFACL:
+		case OBJECT_DEFAULT:
+		case OBJECT_DOMAIN:
+		case OBJECT_DOMCONSTRAINT:
+		case OBJECT_EXTENSION:
+		case OBJECT_FDW:
+		case OBJECT_FOREIGN_SERVER:
+		case OBJECT_FOREIGN_TABLE:
+		case OBJECT_FUNCTION:
+		case OBJECT_INDEX:
+		case OBJECT_LANGUAGE:
+		case OBJECT_LARGEOBJECT:
+		case OBJECT_MATVIEW:
+		case OBJECT_OPCLASS:
+		case OBJECT_OPERATOR:
+		case OBJECT_OPFAMILY:
+		case OBJECT_POLICY:
+		case OBJECT_PROCEDURE:
+		case OBJECT_PUBLICATION:
+		case OBJECT_PUBLICATION_NAMESPACE:
+		case OBJECT_PUBLICATION_REL:
+		case OBJECT_ROUTINE:
+		case OBJECT_RULE:
+		case OBJECT_SCHEMA:
+		case OBJECT_SEQUENCE:
+		case OBJECT_SUBSCRIPTION:
+		case OBJECT_STATISTIC_EXT:
+		case OBJECT_TABCONSTRAINT:
+		case OBJECT_TABLE:
+		case OBJECT_TRANSFORM:
+		case OBJECT_TRIGGER:
+		case OBJECT_TSCONFIGURATION:
+		case OBJECT_TSDICTIONARY:
+		case OBJECT_TSPARSER:
+		case OBJECT_TSTEMPLATE:
+		case OBJECT_TYPE:
+		case OBJECT_USER_MAPPING:
+		case OBJECT_VIEW:
+			return true;
+
+			/*
+			 * There's intentionally no default: case here; we want the
+			 * compiler to warn if a new ObjectType hasn't been handled above.
+			 */
+	}
+
+	/* Shouldn't get here, but if we do, say "no support" */
+	return false;
+}
+
+/*
+ * Do event triggers support this object class?
+ */
+bool
+EventTriggerSupportsObjectClass(ObjectClass objclass)
+{
+	switch (objclass)
+	{
+		case OCLASS_DATABASE:
+		case OCLASS_TBLSPACE:
+		case OCLASS_ROLE:
+		case OCLASS_PARAMETER_ACL:
+			/* no support for global objects */
+			return false;
+		case OCLASS_EVENT_TRIGGER:
+			/* no support for event triggers on event triggers */
+			return false;
+		case OCLASS_CLASS:
+		case OCLASS_PROC:
+		case OCLASS_TYPE:
+		case OCLASS_CAST:
+		case OCLASS_COLLATION:
+		case OCLASS_CONSTRAINT:
+		case OCLASS_CONVERSION:
+		case OCLASS_DEFAULT:
+		case OCLASS_LANGUAGE:
+		case OCLASS_LARGEOBJECT:
+		case OCLASS_OPERATOR:
+		case OCLASS_OPCLASS:
+		case OCLASS_OPFAMILY:
+		case OCLASS_AM:
+		case OCLASS_AMOP:
+		case OCLASS_AMPROC:
+		case OCLASS_REWRITE:
+		case OCLASS_TRIGGER:
+		case OCLASS_SCHEMA:
+		case OCLASS_STATISTIC_EXT:
+		case OCLASS_TSPARSER:
+		case OCLASS_TSDICT:
+		case OCLASS_TSTEMPLATE:
+		case OCLASS_TSCONFIG:
+		case OCLASS_FDW:
+		case OCLASS_FOREIGN_SERVER:
+		case OCLASS_USER_MAPPING:
+		case OCLASS_DEFACL:
+		case OCLASS_EXTENSION:
+		case OCLASS_POLICY:
+		case OCLASS_PUBLICATION:
+		case OCLASS_PUBLICATION_NAMESPACE:
+		case OCLASS_PUBLICATION_REL:
+		case OCLASS_SUBSCRIPTION:
+		case OCLASS_TRANSFORM:
+			return true;
+
+			/*
+			 * There's intentionally no default: case here; we want the
+			 * compiler to warn if a new OCLASS hasn't been handled above.
+			 */
+	}
+
+	/* Shouldn't get here, but if we do, say "no support" */
+	return false;
+}
+
+/*
+ * Prepare event trigger state for a new complete query to run, if necessary;
+ * returns whether this was done.  If it was, EventTriggerEndCompleteQuery must
+ * be called when the query is done, regardless of whether it succeeds or fails
+ * -- so use of a PG_TRY block is mandatory.
+ */
+bool
+EventTriggerBeginCompleteQuery(void)
+{
+	EventTriggerQueryState *state;
+	MemoryContext cxt;
+
+	/*
+	 * Currently, sql_drop, table_rewrite, ddl_command_end events are the only
+	 * reason to have event trigger state at all; so if there are none, don't
+	 * install one.
+	 */
+	if (!trackDroppedObjectsNeeded())
+		return false;
+
+	cxt = AllocSetContextCreate(TopMemoryContext,
+								"event trigger state",
+								ALLOCSET_DEFAULT_SIZES);
+	state = MemoryContextAlloc(cxt, sizeof(EventTriggerQueryState));
+	state->cxt = cxt;
+	slist_init(&(state->SQLDropList));
+	state->in_sql_drop = false;
+	state->table_rewrite_oid = InvalidOid;
+
+	state->commandCollectionInhibited = currentEventTriggerState ?
+		currentEventTriggerState->commandCollectionInhibited : false;
+	state->currentCommand = NULL;
+	state->commandList = NIL;
+	state->previous = currentEventTriggerState;
+	currentEventTriggerState = state;
+
+	return true;
+}
+
+/*
+ * Query completed (or errored out) -- clean up local state, return to previous
+ * one.
+ *
+ * Note: it's an error to call this routine if EventTriggerBeginCompleteQuery
+ * returned false previously.
+ *
+ * Note: this might be called in the PG_CATCH block of a failing transaction,
+ * so be wary of running anything unnecessary.  (In particular, it's probably
+ * unwise to try to allocate memory.)
+ */
+void
+EventTriggerEndCompleteQuery(void)
+{
+	EventTriggerQueryState *prevstate;
+
+	prevstate = currentEventTriggerState->previous;
+
+	/* this avoids the need for retail pfree of SQLDropList items: */
+	MemoryContextDelete(currentEventTriggerState->cxt);
+
+	currentEventTriggerState = prevstate;
+}
+
+/*
+ * Do we need to keep close track of objects being dropped?
+ *
+ * This is useful because there is a cost to running with them enabled.
+ */
+bool
+trackDroppedObjectsNeeded(void)
+{
+	/*
+	 * true if any sql_drop, table_rewrite, ddl_command_end event trigger
+	 * exists
+	 */
+	return list_length(EventCacheLookup(EVT_SQLDrop)) > 0 ||
+		list_length(EventCacheLookup(EVT_TableRewrite)) > 0 ||
+		list_length(EventCacheLookup(EVT_DDLCommandEnd)) > 0;
+}
+
+/*
+ * Support for dropped objects information on event trigger functions.
+ *
+ * We keep the list of objects dropped by the current command in current
+ * state's SQLDropList (comprising SQLDropObject items).  Each time a new
+ * command is to start, a clean EventTriggerQueryState is created; commands
+ * that drop objects do the dependency.c dance to drop objects, which
+ * populates the current state's SQLDropList; when the event triggers are
+ * invoked they can consume the list via pg_event_trigger_dropped_objects().
+ * When the command finishes, the EventTriggerQueryState is cleared, and
+ * the one from the previous command is restored (when no command is in
+ * execution, the current state is NULL).
+ *
+ * All this lets us support the case that an event trigger function drops
+ * objects "reentrantly".
+ */
+
+/*
+ * Register one object as being dropped by the current command.
+ */
+void
+EventTriggerSQLDropAddObject(const ObjectAddress *object, bool original, bool normal)
+{
+	SQLDropObject *obj;
+	MemoryContext oldcxt;
+
+	if (!currentEventTriggerState)
+		return;
+
+	Assert(EventTriggerSupportsObjectClass(getObjectClass(object)));
+
+	/* don't report temp schemas except my own */
+	if (object->classId == NamespaceRelationId &&
+		(isAnyTempNamespace(object->objectId) &&
+		 !isTempNamespace(object->objectId)))
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	obj = palloc0(sizeof(SQLDropObject));
+	obj->address = *object;
+	obj->original = original;
+	obj->normal = normal;
+
+	/*
+	 * Obtain schema names from the object's catalog tuple, if one exists;
+	 * this lets us skip objects in temp schemas.  We trust that
+	 * ObjectProperty contains all object classes that can be
+	 * schema-qualified.
+	 */
+	if (is_objectclass_supported(object->classId))
+	{
+		Relation	catalog;
+		HeapTuple	tuple;
+
+		catalog = table_open(obj->address.classId, AccessShareLock);
+		tuple = get_catalog_object_by_oid(catalog,
+										  get_object_attnum_oid(object->classId),
+										  obj->address.objectId);
+
+		if (tuple)
+		{
+			AttrNumber	attnum;
+			Datum		datum;
+			bool		isnull;
+
+			attnum = get_object_attnum_namespace(obj->address.classId);
+			if (attnum != InvalidAttrNumber)
+			{
+				datum = heap_getattr(tuple, attnum,
+									 RelationGetDescr(catalog), &isnull);
+				if (!isnull)
+				{
+					Oid			namespaceId;
+
+					namespaceId = DatumGetObjectId(datum);
+					/* temp objects are only reported if they are my own */
+					if (isTempNamespace(namespaceId))
+					{
+						obj->schemaname = "pg_temp";
+						obj->istemp = true;
+					}
+					else if (isAnyTempNamespace(namespaceId))
+					{
+						pfree(obj);
+						table_close(catalog, AccessShareLock);
+						MemoryContextSwitchTo(oldcxt);
+						return;
+					}
+					else
+					{
+						obj->schemaname = get_namespace_name(namespaceId);
+						obj->istemp = false;
+					}
+				}
+			}
+
+			if (get_object_namensp_unique(obj->address.classId) &&
+				obj->address.objectSubId == 0)
+			{
+				attnum = get_object_attnum_name(obj->address.classId);
+				if (attnum != InvalidAttrNumber)
+				{
+					datum = heap_getattr(tuple, attnum,
+										 RelationGetDescr(catalog), &isnull);
+					if (!isnull)
+						obj->objname = pstrdup(NameStr(*DatumGetName(datum)));
+				}
+			}
+		}
+
+		table_close(catalog, AccessShareLock);
+	}
+	else
+	{
+		if (object->classId == NamespaceRelationId &&
+			isTempNamespace(object->objectId))
+			obj->istemp = true;
+	}
+
+	/* object identity, objname and objargs */
+	obj->objidentity =
+		getObjectIdentityParts(&obj->address, &obj->addrnames, &obj->addrargs,
+							   false);
+
+	/* object type */
+	obj->objecttype = getObjectTypeDescription(&obj->address, false);
+
+	slist_push_head(&(currentEventTriggerState->SQLDropList), &obj->next);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * pg_event_trigger_dropped_objects
+ *
+ * Make the list of dropped objects available to the user function run by the
+ * Event Trigger.
+ */
+Datum
+pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
+{
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	slist_iter	iter;
+
+	/*
+	 * Protect this function from being called out of context
+	 */
+	if (!currentEventTriggerState ||
+		!currentEventTriggerState->in_sql_drop)
+		ereport(ERROR,
+				(errcode(ERRCODE_E_R_I_E_EVENT_TRIGGER_PROTOCOL_VIOLATED),
+				 errmsg("%s can only be called in a sql_drop event trigger function",
+						"pg_event_trigger_dropped_objects()")));
+
+	/* Build tuplestore to hold the result rows */
+	InitMaterializedSRF(fcinfo, 0);
+
+	slist_foreach(iter, &(currentEventTriggerState->SQLDropList))
+	{
+		SQLDropObject *obj;
+		int			i = 0;
+		Datum		values[12];
+		bool		nulls[12];
+
+		obj = slist_container(SQLDropObject, next, iter.cur);
+
+		MemSet(values, 0, sizeof(values));
+		MemSet(nulls, 0, sizeof(nulls));
+
+		/* classid */
+		values[i++] = ObjectIdGetDatum(obj->address.classId);
+
+		/* objid */
+		values[i++] = ObjectIdGetDatum(obj->address.objectId);
+
+		/* objsubid */
+		values[i++] = Int32GetDatum(obj->address.objectSubId);
+
+		/* original */
+		values[i++] = BoolGetDatum(obj->original);
+
+		/* normal */
+		values[i++] = BoolGetDatum(obj->normal);
+
+		/* is_temporary */
+		values[i++] = BoolGetDatum(obj->istemp);
+
+		/* object_type */
+		values[i++] = CStringGetTextDatum(obj->objecttype);
+
+		/* schema_name */
+		if (obj->schemaname)
+			values[i++] = CStringGetTextDatum(obj->schemaname);
+		else
+			nulls[i++] = true;
+
+		/* object_name */
+		if (obj->objname)
+			values[i++] = CStringGetTextDatum(obj->objname);
+		else
+			nulls[i++] = true;
+
+		/* object_identity */
+		if (obj->objidentity)
+			values[i++] = CStringGetTextDatum(obj->objidentity);
+		else
+			nulls[i++] = true;
+
+		/* address_names and address_args */
+		if (obj->addrnames)
+		{
+			values[i++] = PointerGetDatum(strlist_to_textarray(obj->addrnames));
+
+			if (obj->addrargs)
+				values[i++] = PointerGetDatum(strlist_to_textarray(obj->addrargs));
+			else
+				values[i++] = PointerGetDatum(construct_empty_array(TEXTOID));
+		}
+		else
+		{
+			nulls[i++] = true;
+			nulls[i++] = true;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc,
+							 values, nulls);
+	}
+
+	return (Datum) 0;
+}
+
+/*
+ * pg_event_trigger_table_rewrite_oid
+ *
+ * Make the Oid of the table going to be rewritten available to the user
+ * function run by the Event Trigger.
+ */
+Datum
+pg_event_trigger_table_rewrite_oid(PG_FUNCTION_ARGS)
+{
+	/*
+	 * Protect this function from being called out of context
+	 */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->table_rewrite_oid == InvalidOid)
+		ereport(ERROR,
+				(errcode(ERRCODE_E_R_I_E_EVENT_TRIGGER_PROTOCOL_VIOLATED),
+				 errmsg("%s can only be called in a table_rewrite event trigger function",
+						"pg_event_trigger_table_rewrite_oid()")));
+
+	PG_RETURN_OID(currentEventTriggerState->table_rewrite_oid);
+}
+
+/*
+ * pg_event_trigger_table_rewrite_reason
+ *
+ * Make the rewrite reason available to the user.
+ */
+Datum
+pg_event_trigger_table_rewrite_reason(PG_FUNCTION_ARGS)
+{
+	/*
+	 * Protect this function from being called out of context
+	 */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->table_rewrite_reason == 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_E_R_I_E_EVENT_TRIGGER_PROTOCOL_VIOLATED),
+				 errmsg("%s can only be called in a table_rewrite event trigger function",
+						"pg_event_trigger_table_rewrite_reason()")));
+
+	PG_RETURN_INT32(currentEventTriggerState->table_rewrite_reason);
+}
+
+/*-------------------------------------------------------------------------
+ * Support for DDL command deparsing
+ *
+ * The routines below enable an event trigger function to obtain a list of
+ * DDL commands as they are executed.  There are three main pieces to this
+ * feature:
+ *
+ * 1) Within ProcessUtilitySlow, or some sub-routine thereof, each DDL command
+ * adds a struct CollectedCommand representation of itself to the command list,
+ * using the routines below.
+ *
+ * 2) Some time after that, ddl_command_end fires and the command list is made
+ * available to the event trigger function via pg_event_trigger_ddl_commands();
+ * the complete command details are exposed as a column of type pg_ddl_command.
+ *
+ * 3) An extension can install a function capable of taking a value of type
+ * pg_ddl_command and transform it into some external, user-visible and/or
+ * -modifiable representation.
+ *-------------------------------------------------------------------------
+ */
+
+/*
+ * Inhibit DDL command collection.
+ */
+void
+EventTriggerInhibitCommandCollection(void)
+{
+	if (!currentEventTriggerState)
+		return;
+
+	currentEventTriggerState->commandCollectionInhibited = true;
+}
+
+/*
+ * Re-establish DDL command collection.
+ */
+void
+EventTriggerUndoInhibitCommandCollection(void)
+{
+	if (!currentEventTriggerState)
+		return;
+
+	currentEventTriggerState->commandCollectionInhibited = false;
+}
+
+/*
+ * EventTriggerCollectSimpleCommand
+ *		Save data about a simple DDL command that was just executed
+ *
+ * address identifies the object being operated on.  secondaryObject is an
+ * object address that was related in some way to the executed command; its
+ * meaning is command-specific.
+ *
+ * For instance, for an ALTER obj SET SCHEMA command, objtype is the type of
+ * object being moved, objectId is its OID, and secondaryOid is the OID of the
+ * old schema.  (The destination schema OID can be obtained by catalog lookup
+ * of the object.)
+ */
+void
+EventTriggerCollectSimpleCommand(ObjectAddress address,
+								 ObjectAddress secondaryObject,
+								 Node *parsetree)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc(sizeof(CollectedCommand));
+
+	command->type = SCT_Simple;
+	command->in_extension = creating_extension;
+
+	command->d.simple.address = address;
+	command->d.simple.secondaryObject = secondaryObject;
+	command->parsetree = copyObject(parsetree);
+
+	currentEventTriggerState->commandList = lappend(currentEventTriggerState->commandList,
+													command);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerAlterTableStart
+ *		Prepare to receive data on an ALTER TABLE command about to be executed
+ *
+ * Note we don't collect the command immediately; instead we keep it in
+ * currentCommand, and only when we're done processing the subcommands we will
+ * add it to the command list.
+ */
+void
+EventTriggerAlterTableStart(Node *parsetree)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc(sizeof(CollectedCommand));
+
+	command->type = SCT_AlterTable;
+	command->in_extension = creating_extension;
+
+	command->d.alterTable.classId = RelationRelationId;
+	command->d.alterTable.objectId = InvalidOid;
+	command->d.alterTable.subcmds = NIL;
+	command->parsetree = copyObject(parsetree);
+
+	command->parent = currentEventTriggerState->currentCommand;
+	currentEventTriggerState->currentCommand = command;
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * Remember the OID of the object being affected by an ALTER TABLE.
+ *
+ * This is needed because in some cases we don't know the OID until later.
+ */
+void
+EventTriggerAlterTableRelid(Oid objectId)
+{
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	currentEventTriggerState->currentCommand->d.alterTable.objectId = objectId;
+}
+
+/*
+ * EventTriggerCollectAlterTableSubcmd
+ *		Save data about a single part of an ALTER TABLE.
+ *
+ * Several different commands go through this path, but apart from ALTER TABLE
+ * itself, they are all concerned with AlterTableCmd nodes that are generated
+ * internally, so that's all that this code needs to handle at the moment.
+ */
+void
+EventTriggerCollectAlterTableSubcmd(Node *subcmd, ObjectAddress address)
+{
+	MemoryContext oldcxt;
+	CollectedATSubcmd *newsub;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	Assert(IsA(subcmd, AlterTableCmd));
+	Assert(currentEventTriggerState->currentCommand != NULL);
+	Assert(OidIsValid(currentEventTriggerState->currentCommand->d.alterTable.objectId));
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	newsub = palloc(sizeof(CollectedATSubcmd));
+	newsub->address = address;
+	newsub->parsetree = copyObject(subcmd);
+
+	currentEventTriggerState->currentCommand->d.alterTable.subcmds =
+		lappend(currentEventTriggerState->currentCommand->d.alterTable.subcmds, newsub);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerAlterTableEnd
+ *		Finish up saving an ALTER TABLE command, and add it to command list.
+ *
+ * FIXME this API isn't considering the possibility that an xact/subxact is
+ * aborted partway through.  Probably it's best to add an
+ * AtEOSubXact_EventTriggers() to fix this.
+ */
+void
+EventTriggerAlterTableEnd(void)
+{
+	CollectedCommand *parent;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	parent = currentEventTriggerState->currentCommand->parent;
+
+	/* If no subcommands, don't collect */
+	if (list_length(currentEventTriggerState->currentCommand->d.alterTable.subcmds) != 0)
+	{
+		MemoryContext oldcxt;
+
+		oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+		currentEventTriggerState->commandList =
+			lappend(currentEventTriggerState->commandList,
+					currentEventTriggerState->currentCommand);
+
+		MemoryContextSwitchTo(oldcxt);
+	}
+	else
+		pfree(currentEventTriggerState->currentCommand);
+
+	currentEventTriggerState->currentCommand = parent;
+}
+
+/*
+ * EventTriggerCollectGrant
+ *		Save data about a GRANT/REVOKE command being executed
+ *
+ * This function creates a copy of the InternalGrant, as the original might
+ * not have the right lifetime.
+ */
+void
+EventTriggerCollectGrant(InternalGrant *istmt)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+	InternalGrant *icopy;
+	ListCell   *cell;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	/*
+	 * This is tedious, but necessary.
+	 */
+	icopy = palloc(sizeof(InternalGrant));
+	memcpy(icopy, istmt, sizeof(InternalGrant));
+	icopy->objects = list_copy(istmt->objects);
+	icopy->grantees = list_copy(istmt->grantees);
+	icopy->col_privs = NIL;
+	foreach(cell, istmt->col_privs)
+		icopy->col_privs = lappend(icopy->col_privs, copyObject(lfirst(cell)));
+
+	/* Now collect it, using the copied InternalGrant */
+	command = palloc(sizeof(CollectedCommand));
+	command->type = SCT_Grant;
+	command->in_extension = creating_extension;
+	command->d.grant.istmt = icopy;
+	command->parsetree = NULL;
+
+	currentEventTriggerState->commandList =
+		lappend(currentEventTriggerState->commandList, command);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerCollectAlterOpFam
+ *		Save data about an ALTER OPERATOR FAMILY ADD/DROP command being
+ *		executed
+ */
+void
+EventTriggerCollectAlterOpFam(AlterOpFamilyStmt *stmt, Oid opfamoid,
+							  List *operators, List *procedures)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc(sizeof(CollectedCommand));
+	command->type = SCT_AlterOpFamily;
+	command->in_extension = creating_extension;
+	ObjectAddressSet(command->d.opfam.address,
+					 OperatorFamilyRelationId, opfamoid);
+	command->d.opfam.operators = operators;
+	command->d.opfam.procedures = procedures;
+	command->parsetree = (Node *) copyObject(stmt);
+
+	currentEventTriggerState->commandList =
+		lappend(currentEventTriggerState->commandList, command);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerCollectCreateOpClass
+ *		Save data about a CREATE OPERATOR CLASS command being executed
+ */
+void
+EventTriggerCollectCreateOpClass(CreateOpClassStmt *stmt, Oid opcoid,
+								 List *operators, List *procedures)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc0(sizeof(CollectedCommand));
+	command->type = SCT_CreateOpClass;
+	command->in_extension = creating_extension;
+	ObjectAddressSet(command->d.createopc.address,
+					 OperatorClassRelationId, opcoid);
+	command->d.createopc.operators = operators;
+	command->d.createopc.procedures = procedures;
+	command->parsetree = (Node *) copyObject(stmt);
+
+	currentEventTriggerState->commandList =
+		lappend(currentEventTriggerState->commandList, command);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerCollectAlterTSConfig
+ *		Save data about an ALTER TEXT SEARCH CONFIGURATION command being
+ *		executed
+ */
+void
+EventTriggerCollectAlterTSConfig(AlterTSConfigurationStmt *stmt, Oid cfgId,
+								 Oid *dictIds, int ndicts)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc0(sizeof(CollectedCommand));
+	command->type = SCT_AlterTSConfig;
+	command->in_extension = creating_extension;
+	ObjectAddressSet(command->d.atscfg.address,
+					 TSConfigRelationId, cfgId);
+	command->d.atscfg.dictIds = palloc(sizeof(Oid) * ndicts);
+	memcpy(command->d.atscfg.dictIds, dictIds, sizeof(Oid) * ndicts);
+	command->d.atscfg.ndicts = ndicts;
+	command->parsetree = (Node *) copyObject(stmt);
+
+	currentEventTriggerState->commandList =
+		lappend(currentEventTriggerState->commandList, command);
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * EventTriggerCollectAlterDefPrivs
+ *		Save data about an ALTER DEFAULT PRIVILEGES command being
+ *		executed
+ */
+void
+EventTriggerCollectAlterDefPrivs(AlterDefaultPrivilegesStmt *stmt)
+{
+	MemoryContext oldcxt;
+	CollectedCommand *command;
+
+	/* ignore if event trigger context not set, or collection disabled */
+	if (!currentEventTriggerState ||
+		currentEventTriggerState->commandCollectionInhibited)
+		return;
+
+	oldcxt = MemoryContextSwitchTo(currentEventTriggerState->cxt);
+
+	command = palloc0(sizeof(CollectedCommand));
+	command->type = SCT_AlterDefaultPrivileges;
+	command->d.defprivs.objtype = stmt->action->objtype;
+	command->in_extension = creating_extension;
+	command->parsetree = (Node *) copyObject(stmt);
+
+	currentEventTriggerState->commandList =
+		lappend(currentEventTriggerState->commandList, command);
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * In a ddl_command_end event trigger, this function reports the DDL commands
+ * being run.
+ */
+Datum
+pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
+{
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	ListCell   *lc;
+
+	/*
+	 * Protect this function from being called out of context
+	 */
+	if (!currentEventTriggerState)
+		ereport(ERROR,
+				(errcode(ERRCODE_E_R_I_E_EVENT_TRIGGER_PROTOCOL_VIOLATED),
+				 errmsg("%s can only be called in an event trigger function",
+						"pg_event_trigger_ddl_commands()")));
+
+	/* Build tuplestore to hold the result rows */
+	InitMaterializedSRF(fcinfo, 0);
+
+	foreach(lc, currentEventTriggerState->commandList)
+	{
+		CollectedCommand *cmd = lfirst(lc);
+		Datum		values[9];
+		bool		nulls[9];
+		ObjectAddress addr;
+		int			i = 0;
+
+		/*
+		 * For IF NOT EXISTS commands that attempt to create an existing
+		 * object, the returned OID is Invalid.  Don't return anything.
+		 *
+		 * One might think that a viable alternative would be to look up the
+		 * Oid of the existing object and run the deparse with that.  But
+		 * since the parse tree might be different from the one that created
+		 * the object in the first place, we might not end up in a consistent
+		 * state anyway.
+		 */
+		if (cmd->type == SCT_Simple &&
+			!OidIsValid(cmd->d.simple.address.objectId))
+			continue;
+
+		MemSet(nulls, 0, sizeof(nulls));
+
+		switch (cmd->type)
+		{
+			case SCT_Simple:
+			case SCT_AlterTable:
+			case SCT_AlterOpFamily:
+			case SCT_CreateOpClass:
+			case SCT_AlterTSConfig:
+				{
+					char	   *identity;
+					char	   *type;
+					char	   *schema = NULL;
+
+					if (cmd->type == SCT_Simple)
+						addr = cmd->d.simple.address;
+					else if (cmd->type == SCT_AlterTable)
+						ObjectAddressSet(addr,
+										 cmd->d.alterTable.classId,
+										 cmd->d.alterTable.objectId);
+					else if (cmd->type == SCT_AlterOpFamily)
+						addr = cmd->d.opfam.address;
+					else if (cmd->type == SCT_CreateOpClass)
+						addr = cmd->d.createopc.address;
+					else if (cmd->type == SCT_AlterTSConfig)
+						addr = cmd->d.atscfg.address;
+
+					/*
+					 * If an object was dropped in the same command we may end
+					 * up in a situation where we generated a message but can
+					 * no longer look for the object information, so skip it
+					 * rather than failing.  This can happen for example with
+					 * some subcommand combinations of ALTER TABLE.
+					 */
+					identity = getObjectIdentity(&addr, true);
+					if (identity == NULL)
+						continue;
+
+					/* The type can never be NULL. */
+					type = getObjectTypeDescription(&addr, true);
+
+					/*
+					 * Obtain schema name, if any ("pg_temp" if a temp
+					 * object). If the object class is not in the supported
+					 * list here, we assume it's a schema-less object type,
+					 * and thus "schema" remains set to NULL.
+					 */
+					if (is_objectclass_supported(addr.classId))
+					{
+						AttrNumber	nspAttnum;
+
+						nspAttnum = get_object_attnum_namespace(addr.classId);
+						if (nspAttnum != InvalidAttrNumber)
+						{
+							Relation	catalog;
+							HeapTuple	objtup;
+							Oid			schema_oid;
+							bool		isnull;
+
+							catalog = table_open(addr.classId, AccessShareLock);
+							objtup = get_catalog_object_by_oid(catalog,
+															   get_object_attnum_oid(addr.classId),
+															   addr.objectId);
+							if (!HeapTupleIsValid(objtup))
+								elog(ERROR, "cache lookup failed for object %u/%u",
+									 addr.classId, addr.objectId);
+							schema_oid =
+								heap_getattr(objtup, nspAttnum,
+											 RelationGetDescr(catalog), &isnull);
+							if (isnull)
+								elog(ERROR,
+									 "invalid null namespace in object %u/%u/%d",
+									 addr.classId, addr.objectId, addr.objectSubId);
+							schema = get_namespace_name_or_temp(schema_oid);
+
+							table_close(catalog, AccessShareLock);
+						}
+					}
+
+					/* classid */
+					values[i++] = ObjectIdGetDatum(addr.classId);
+					/* objid */
+					values[i++] = ObjectIdGetDatum(addr.objectId);
+					/* objsubid */
+					values[i++] = Int32GetDatum(addr.objectSubId);
+					/* command tag */
+					values[i++] = CStringGetTextDatum(CreateCommandName(cmd->parsetree));
+					/* object_type */
+					values[i++] = CStringGetTextDatum(type);
+					/* schema */
+					if (schema == NULL)
+						nulls[i++] = true;
+					else
+						values[i++] = CStringGetTextDatum(schema);
+					/* identity */
+					values[i++] = CStringGetTextDatum(identity);
+					/* in_extension */
+					values[i++] = BoolGetDatum(cmd->in_extension);
+					/* command */
+					values[i++] = PointerGetDatum(cmd);
+				}
+				break;
+
+			case SCT_AlterDefaultPrivileges:
+				/* classid */
+				nulls[i++] = true;
+				/* objid */
+				nulls[i++] = true;
+				/* objsubid */
+				nulls[i++] = true;
+				/* command tag */
+				values[i++] = CStringGetTextDatum(CreateCommandName(cmd->parsetree));
+				/* object_type */
+				values[i++] = CStringGetTextDatum(stringify_adefprivs_objtype(cmd->d.defprivs.objtype));
+				/* schema */
+				nulls[i++] = true;
+				/* identity */
+				nulls[i++] = true;
+				/* in_extension */
+				values[i++] = BoolGetDatum(cmd->in_extension);
+				/* command */
+				values[i++] = PointerGetDatum(cmd);
+				break;
+
+			case SCT_Grant:
+				/* classid */
+				nulls[i++] = true;
+				/* objid */
+				nulls[i++] = true;
+				/* objsubid */
+				nulls[i++] = true;
+				/* command tag */
+				values[i++] = CStringGetTextDatum(cmd->d.grant.istmt->is_grant ?
+												  "GRANT" : "REVOKE");
+				/* object_type */
+				values[i++] = CStringGetTextDatum(stringify_grant_objtype(cmd->d.grant.istmt->objtype));
+				/* schema */
+				nulls[i++] = true;
+				/* identity */
+				nulls[i++] = true;
+				/* in_extension */
+				values[i++] = BoolGetDatum(cmd->in_extension);
+				/* command */
+				values[i++] = PointerGetDatum(cmd);
+				break;
+		}
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc,
+							 values, nulls);
+	}
+
+	PG_RETURN_VOID();
+}
+
+/*
+ * Return the ObjectType as a string, as it would appear in GRANT and
+ * REVOKE commands.
+ */
+static const char *
+stringify_grant_objtype(ObjectType objtype)
+{
+	switch (objtype)
+	{
+		case OBJECT_COLUMN:
+			return "COLUMN";
+		case OBJECT_TABLE:
+			return "TABLE";
+		case OBJECT_SEQUENCE:
+			return "SEQUENCE";
+		case OBJECT_DATABASE:
+			return "DATABASE";
+		case OBJECT_DOMAIN:
+			return "DOMAIN";
+		case OBJECT_FDW:
+			return "FOREIGN DATA WRAPPER";
+		case OBJECT_FOREIGN_SERVER:
+			return "FOREIGN SERVER";
+		case OBJECT_FUNCTION:
+			return "FUNCTION";
+		case OBJECT_LANGUAGE:
+			return "LANGUAGE";
+		case OBJECT_LARGEOBJECT:
+			return "LARGE OBJECT";
+		case OBJECT_SCHEMA:
+			return "SCHEMA";
+		case OBJECT_PARAMETER_ACL:
+			return "PARAMETER";
+		case OBJECT_PROCEDURE:
+			return "PROCEDURE";
+		case OBJECT_ROUTINE:
+			return "ROUTINE";
+		case OBJECT_TABLESPACE:
+			return "TABLESPACE";
+		case OBJECT_TYPE:
+			return "TYPE";
+			/* these currently aren't used */
+		case OBJECT_ACCESS_METHOD:
+		case OBJECT_AGGREGATE:
+		case OBJECT_AMOP:
+		case OBJECT_AMPROC:
+		case OBJECT_ATTRIBUTE:
+		case OBJECT_CAST:
+		case OBJECT_COLLATION:
+		case OBJECT_CONVERSION:
+		case OBJECT_DEFAULT:
+		case OBJECT_DEFACL:
+		case OBJECT_DOMCONSTRAINT:
+		case OBJECT_EVENT_TRIGGER:
+		case OBJECT_EXTENSION:
+		case OBJECT_FOREIGN_TABLE:
+		case OBJECT_INDEX:
+		case OBJECT_MATVIEW:
+		case OBJECT_OPCLASS:
+		case OBJECT_OPERATOR:
+		case OBJECT_OPFAMILY:
+		case OBJECT_POLICY:
+		case OBJECT_PUBLICATION:
+		case OBJECT_PUBLICATION_NAMESPACE:
+		case OBJECT_PUBLICATION_REL:
+		case OBJECT_ROLE:
+		case OBJECT_RULE:
+		case OBJECT_STATISTIC_EXT:
+		case OBJECT_SUBSCRIPTION:
+		case OBJECT_TABCONSTRAINT:
+		case OBJECT_TRANSFORM:
+		case OBJECT_TRIGGER:
+		case OBJECT_TSCONFIGURATION:
+		case OBJECT_TSDICTIONARY:
+		case OBJECT_TSPARSER:
+		case OBJECT_TSTEMPLATE:
+		case OBJECT_USER_MAPPING:
+		case OBJECT_VIEW:
+			elog(ERROR, "unsupported object type: %d", (int) objtype);
+	}
+
+	return "???";				/* keep compiler quiet */
+}
+
+/*
+ * Return the ObjectType as a string; as above, but use the spelling
+ * in ALTER DEFAULT PRIVILEGES commands instead.  Generally this is just
+ * the plural.
+ */
+static const char *
+stringify_adefprivs_objtype(ObjectType objtype)
+{
+	switch (objtype)
+	{
+		case OBJECT_COLUMN:
+			return "COLUMNS";
+		case OBJECT_TABLE:
+			return "TABLES";
+		case OBJECT_SEQUENCE:
+			return "SEQUENCES";
+		case OBJECT_DATABASE:
+			return "DATABASES";
+		case OBJECT_DOMAIN:
+			return "DOMAINS";
+		case OBJECT_FDW:
+			return "FOREIGN DATA WRAPPERS";
+		case OBJECT_FOREIGN_SERVER:
+			return "FOREIGN SERVERS";
+		case OBJECT_FUNCTION:
+			return "FUNCTIONS";
+		case OBJECT_LANGUAGE:
+			return "LANGUAGES";
+		case OBJECT_LARGEOBJECT:
+			return "LARGE OBJECTS";
+		case OBJECT_SCHEMA:
+			return "SCHEMAS";
+		case OBJECT_PROCEDURE:
+			return "PROCEDURES";
+		case OBJECT_ROUTINE:
+			return "ROUTINES";
+		case OBJECT_TABLESPACE:
+			return "TABLESPACES";
+		case OBJECT_TYPE:
+			return "TYPES";
+			/* these currently aren't used */
+		case OBJECT_ACCESS_METHOD:
+		case OBJECT_AGGREGATE:
+		case OBJECT_AMOP:
+		case OBJECT_AMPROC:
+		case OBJECT_ATTRIBUTE:
+		case OBJECT_CAST:
+		case OBJECT_COLLATION:
+		case OBJECT_CONVERSION:
+		case OBJECT_DEFAULT:
+		case OBJECT_DEFACL:
+		case OBJECT_DOMCONSTRAINT:
+		case OBJECT_EVENT_TRIGGER:
+		case OBJECT_EXTENSION:
+		case OBJECT_FOREIGN_TABLE:
+		case OBJECT_INDEX:
+		case OBJECT_MATVIEW:
+		case OBJECT_OPCLASS:
+		case OBJECT_OPERATOR:
+		case OBJECT_OPFAMILY:
+		case OBJECT_PARAMETER_ACL:
+		case OBJECT_POLICY:
+		case OBJECT_PUBLICATION:
+		case OBJECT_PUBLICATION_NAMESPACE:
+		case OBJECT_PUBLICATION_REL:
+		case OBJECT_ROLE:
+		case OBJECT_RULE:
+		case OBJECT_STATISTIC_EXT:
+		case OBJECT_SUBSCRIPTION:
+		case OBJECT_TABCONSTRAINT:
+		case OBJECT_TRANSFORM:
+		case OBJECT_TRIGGER:
+		case OBJECT_TSCONFIGURATION:
+		case OBJECT_TSDICTIONARY:
+		case OBJECT_TSPARSER:
+		case OBJECT_TSTEMPLATE:
+		case OBJECT_USER_MAPPING:
+		case OBJECT_VIEW:
+			elog(ERROR, "unsupported object type: %d", (int) objtype);
+	}
+
+	return "???";				/* keep compiler quiet */
+}