/*
* Rename language
*/
void
RenameLanguage(const char *oldname, const char *newname)
{
HeapTuple tup;
Relation rel;
rel = heap_open(LanguageRelationId, RowExclusiveLock);
tup = SearchSysCacheCopy1(LANGNAME, CStringGetDatum(oldname));
if (!HeapTupleIsValid(tup))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("language \"%s\" does not exist", oldname)));
/* make sure the new name doesn't exist */
if (SearchSysCacheExists1(LANGNAME, CStringGetDatum(newname)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("language \"%s\" already exists", newname)));
/* must be owner of PL */
if (!pg_language_ownercheck(HeapTupleGetOid(tup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_LANGUAGE,
oldname);
/* rename */
namestrcpy(&(((Form_pg_language) GETSTRUCT(tup))->lanname), newname);
simple_heap_update(rel, &tup->t_self, tup);
CatalogUpdateIndexes(rel, tup);
heap_close(rel, NoLock);
heap_freetuple(tup);
}
Datum
lastval(PG_FUNCTION_ARGS)
{
Relation seqrel;
int64 result;
if (last_used_seq == NULL)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("lastval is not yet defined in this session")));
/* Someone may have dropped the sequence since the last nextval() */
if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(last_used_seq->relid)))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("lastval is not yet defined in this session")));
seqrel = open_share_lock(last_used_seq);
/* nextval() must have already been called for this sequence */
Assert(last_used_seq->last_valid);
if (pg_class_aclcheck(last_used_seq->relid, GetUserId(),
ACL_SELECT | ACL_USAGE) != ACLCHECK_OK)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied for sequence %s",
RelationGetRelationName(seqrel))));
result = last_used_seq->last;
relation_close(seqrel, NoLock);
PG_RETURN_INT64(result);
}
/* ----------------
* NamespaceCreate
* ---------------
*/
Oid
NamespaceCreate(const char *nspName, Oid ownerId)
{
Relation nspdesc;
HeapTuple tup;
Oid nspoid;
bool nulls[Natts_pg_namespace];
Datum values[Natts_pg_namespace];
NameData nname;
TupleDesc tupDesc;
int i;
/* sanity checks */
if (!nspName)
elog(ERROR, "no namespace name supplied");
/* make sure there is no existing namespace of same name */
if (SearchSysCacheExists1(NAMESPACENAME, PointerGetDatum(nspName)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_SCHEMA),
errmsg("schema \"%s\" already exists", nspName)));
/* initialize nulls and values */
for (i = 0; i < Natts_pg_namespace; i++)
{
nulls[i] = false;
values[i] = (Datum) NULL;
}
namestrcpy(&nname, nspName);
values[Anum_pg_namespace_nspname - 1] = NameGetDatum(&nname);
values[Anum_pg_namespace_nspowner - 1] = ObjectIdGetDatum(ownerId);
nulls[Anum_pg_namespace_nspacl - 1] = true;
nspdesc = heap_open(NamespaceRelationId, RowExclusiveLock);
tupDesc = nspdesc->rd_att;
tup = heap_form_tuple(tupDesc, values, nulls);
nspoid = simple_heap_insert(nspdesc, tup);
Assert(OidIsValid(nspoid));
CatalogUpdateIndexes(nspdesc, tup);
heap_close(nspdesc, RowExclusiveLock);
/* Record dependency on owner */
recordDependencyOnOwner(NamespaceRelationId, nspoid, ownerId);
/* Post creation hook for new schema */
InvokeObjectAccessHook(OAT_POST_CREATE, NamespaceRelationId, nspoid, 0);
return nspoid;
}
/**
* @fn Datum get_table_and_inheritors(PG_FUNCTION_ARGS)
* @brief Return array containing Oids of parent table and its children.
* Note that this function does not release relation locks.
*
* get_table_and_inheritors(table)
*
* @param table parent table.
* @retval regclass[]
*/
Datum
repack_get_table_and_inheritors(PG_FUNCTION_ARGS)
{
Oid parent = PG_GETARG_OID(0);
List *relations;
Datum *relations_array;
int relations_array_size;
ArrayType *result;
ListCell *lc;
int i;
LockRelationOid(parent, AccessShareLock);
/* Check that parent table exists */
if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(parent)))
PG_RETURN_ARRAYTYPE_P(construct_empty_array(OIDOID));
/* Also check that children exist */
relations = find_all_inheritors(parent, AccessShareLock, NULL);
relations_array_size = list_length(relations);
if (relations_array_size == 0)
PG_RETURN_ARRAYTYPE_P(construct_empty_array(OIDOID));
relations_array = palloc(relations_array_size * sizeof(Datum));
i = 0;
foreach (lc, relations)
relations_array[i++] = ObjectIdGetDatum(lfirst_oid(lc));
result = construct_array(relations_array,
relations_array_size,
OIDOID, sizeof(Oid),
true, 'i');
pfree(relations_array);
PG_RETURN_ARRAYTYPE_P(result);
}
/*
* CREATE SCHEMA
*/
Oid
CreateSchemaCommand(CreateSchemaStmt *stmt, const char *queryString)
{
const char *schemaName = stmt->schemaname;
Oid namespaceId;
OverrideSearchPath *overridePath;
List *parsetree_list;
ListCell *parsetree_item;
Oid owner_uid;
Oid saved_uid;
int save_sec_context;
AclResult aclresult;
ObjectAddress address;
GetUserIdAndSecContext(&saved_uid, &save_sec_context);
/*
* Who is supposed to own the new schema?
*/
if (stmt->authrole)
owner_uid = get_rolespec_oid(stmt->authrole, false);
else
owner_uid = saved_uid;
/* fill schema name with the user name if not specified */
if (!schemaName)
{
HeapTuple tuple;
tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(owner_uid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for role %u", owner_uid);
schemaName =
pstrdup(NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname));
ReleaseSysCache(tuple);
}
/*
* To create a schema, must have schema-create privilege on the current
* database and must be able to become the target role (this does not
* imply that the target role itself must have create-schema privilege).
* The latter provision guards against "giveaway" attacks. Note that a
* superuser will always have both of these privileges a fortiori.
*/
aclresult = pg_database_aclcheck(MyDatabaseId, saved_uid, ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_DATABASE,
get_database_name(MyDatabaseId));
check_is_member_of_role(saved_uid, owner_uid);
/* Additional check to protect reserved schema names */
if (!allowSystemTableMods && IsReservedName(schemaName))
ereport(ERROR,
(errcode(ERRCODE_RESERVED_NAME),
errmsg("unacceptable schema name \"%s\"", schemaName),
errdetail("The prefix \"pg_\" is reserved for system schemas.")));
/*
* If if_not_exists was given and the schema already exists, bail out.
* (Note: we needn't check this when not if_not_exists, because
* NamespaceCreate will complain anyway.) We could do this before making
* the permissions checks, but since CREATE TABLE IF NOT EXISTS makes its
* creation-permission check first, we do likewise.
*/
if (stmt->if_not_exists &&
SearchSysCacheExists1(NAMESPACENAME, PointerGetDatum(schemaName)))
{
ereport(NOTICE,
(errcode(ERRCODE_DUPLICATE_SCHEMA),
errmsg("schema \"%s\" already exists, skipping",
schemaName)));
return InvalidOid;
}
/*
* If the requested authorization is different from the current user,
* temporarily set the current user so that the object(s) will be created
* with the correct ownership.
*
* (The setting will be restored at the end of this routine, or in case of
* error, transaction abort will clean things up.)
*/
if (saved_uid != owner_uid)
SetUserIdAndSecContext(owner_uid,
save_sec_context | SECURITY_LOCAL_USERID_CHANGE);
/* Create the schema's namespace */
namespaceId = NamespaceCreate(schemaName, owner_uid, false);
/* Advance cmd counter to make the namespace visible */
CommandCounterIncrement();
/*
* Temporarily make the new namespace be the front of the search path, as
* well as the default creation target namespace. This will be undone at
* the end of this routine, or upon error.
*/
overridePath = GetOverrideSearchPath(CurrentMemoryContext);
overridePath->schemas = lcons_oid(namespaceId, overridePath->schemas);
/* XXX should we clear overridePath->useTemp? */
PushOverrideSearchPath(overridePath);
/*
* Report the new schema to possibly interested event triggers. Note we
* must do this here and not in ProcessUtilitySlow because otherwise the
* objects created below are reported before the schema, which would be
* wrong.
*/
ObjectAddressSet(address, NamespaceRelationId, namespaceId);
EventTriggerCollectSimpleCommand(address, InvalidObjectAddress,
(Node *) stmt);
/*
* Examine the list of commands embedded in the CREATE SCHEMA command, and
* reorganize them into a sequentially executable order with no forward
* references. Note that the result is still a list of raw parsetrees ---
* we cannot, in general, run parse analysis on one statement until we
* have actually executed the prior ones.
*/
parsetree_list = transformCreateSchemaStmt(stmt);
/*
* Execute each command contained in the CREATE SCHEMA. Since the grammar
* allows only utility commands in CREATE SCHEMA, there is no need to pass
* them through parse_analyze() or the rewriter; we can just hand them
* straight to ProcessUtility.
*/
foreach(parsetree_item, parsetree_list)
{
Node *stmt = (Node *) lfirst(parsetree_item);
/* do this step */
ProcessUtility(stmt,
queryString,
PROCESS_UTILITY_SUBCOMMAND,
NULL,
None_Receiver,
NULL);
/* make sure later steps can see the object created here */
CommandCounterIncrement();
}
/*
* find_inheritance_children
*
* Returns a list containing the OIDs of all relations which
* inherit *directly* from the relation with OID 'parentrelId'.
*
* The specified lock type is acquired on each child relation (but not on the
* given rel; caller should already have locked it). If lockmode is NoLock
* then no locks are acquired, but caller must beware of race conditions
* against possible DROPs of child relations.
*/
List *
find_inheritance_children(Oid parentrelId, LOCKMODE lockmode)
{
List *list = NIL;
Relation relation;
SysScanDesc scan;
ScanKeyData key[1];
HeapTuple inheritsTuple;
Oid inhrelid;
Oid *oidarr;
int maxoids,
numoids,
i;
/*
* Can skip the scan if pg_class shows the relation has never had a
* subclass.
*/
if (!has_subclass(parentrelId))
return NIL;
/*
* Scan pg_inherits and build a working array of subclass OIDs.
*/
maxoids = 32;
oidarr = (Oid *) palloc(maxoids * sizeof(Oid));
numoids = 0;
relation = heap_open(InheritsRelationId, AccessShareLock);
ScanKeyInit(&key[0],
Anum_pg_inherits_inhparent,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(parentrelId));
scan = systable_beginscan(relation, InheritsParentIndexId, true,
NULL, 1, key);
while ((inheritsTuple = systable_getnext(scan)) != NULL)
{
inhrelid = ((Form_pg_inherits) GETSTRUCT(inheritsTuple))->inhrelid;
if (numoids >= maxoids)
{
maxoids *= 2;
oidarr = (Oid *) repalloc(oidarr, maxoids * sizeof(Oid));
}
oidarr[numoids++] = inhrelid;
}
systable_endscan(scan);
heap_close(relation, AccessShareLock);
/*
* If we found more than one child, sort them by OID. This ensures
* reasonably consistent behavior regardless of the vagaries of an
* indexscan. This is important since we need to be sure all backends
* lock children in the same order to avoid needless deadlocks.
*/
if (numoids > 1)
qsort(oidarr, numoids, sizeof(Oid), oid_cmp);
/*
* Acquire locks and build the result list.
*/
for (i = 0; i < numoids; i++)
{
inhrelid = oidarr[i];
if (lockmode != NoLock)
{
/* Get the lock to synchronize against concurrent drop */
LockRelationOid(inhrelid, lockmode);
/*
* Now that we have the lock, double-check to see if the relation
* really exists or not. If not, assume it was dropped while we
* waited to acquire lock, and ignore it.
*/
if (!SearchSysCacheExists1(RELOID, ObjectIdGetDatum(inhrelid)))
{
/* Release useless lock */
UnlockRelationOid(inhrelid, lockmode);
/* And ignore this relation */
continue;
}
}
list = lappend_oid(list, inhrelid);
}
pfree(oidarr);
return list;
}
/* ----------------
* NamespaceCreate
*
* Create a namespace (schema) with the given name and owner OID.
*
* If isTemp is true, this schema is a per-backend schema for holding
* temporary tables. Currently, it is used to prevent it from being
* linked as a member of any active extension. (If someone does CREATE
* TEMP TABLE in an extension script, we don't want the temp schema to
* become part of the extension). And to avoid checking for default ACL
* for temp namespace (as it is not necessary).
* ---------------
*/
Oid
NamespaceCreate(const char *nspName, Oid ownerId, bool isTemp)
{
Relation nspdesc;
HeapTuple tup;
Oid nspoid;
bool nulls[Natts_pg_namespace];
Datum values[Natts_pg_namespace];
NameData nname;
TupleDesc tupDesc;
ObjectAddress myself;
int i;
Acl *nspacl;
/* sanity checks */
if (!nspName)
elog(ERROR, "no namespace name supplied");
/* make sure there is no existing namespace of same name */
if (SearchSysCacheExists1(NAMESPACENAME, PointerGetDatum(nspName)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_SCHEMA),
errmsg("schema \"%s\" already exists", nspName)));
if (!isTemp)
nspacl = get_user_default_acl(OBJECT_SCHEMA, ownerId,
InvalidOid);
else
nspacl = NULL;
nspdesc = heap_open(NamespaceRelationId, RowExclusiveLock);
tupDesc = nspdesc->rd_att;
/* initialize nulls and values */
for (i = 0; i < Natts_pg_namespace; i++)
{
nulls[i] = false;
values[i] = (Datum) NULL;
}
nspoid = GetNewOidWithIndex(nspdesc, NamespaceOidIndexId,
Anum_pg_namespace_oid);
values[Anum_pg_namespace_oid - 1] = ObjectIdGetDatum(nspoid);
namestrcpy(&nname, nspName);
values[Anum_pg_namespace_nspname - 1] = NameGetDatum(&nname);
values[Anum_pg_namespace_nspowner - 1] = ObjectIdGetDatum(ownerId);
if (nspacl != NULL)
values[Anum_pg_namespace_nspacl - 1] = PointerGetDatum(nspacl);
else
nulls[Anum_pg_namespace_nspacl - 1] = true;
tup = heap_form_tuple(tupDesc, values, nulls);
CatalogTupleInsert(nspdesc, tup);
Assert(OidIsValid(nspoid));
heap_close(nspdesc, RowExclusiveLock);
/* Record dependencies */
myself.classId = NamespaceRelationId;
myself.objectId = nspoid;
myself.objectSubId = 0;
/* dependency on owner */
recordDependencyOnOwner(NamespaceRelationId, nspoid, ownerId);
/* dependences on roles mentioned in default ACL */
recordDependencyOnNewAcl(NamespaceRelationId, nspoid, 0, ownerId, nspacl);
/* dependency on extension ... but not for magic temp schemas */
if (!isTemp)
recordDependencyOnCurrentExtension(&myself, false);
/* Post creation hook for new schema */
InvokeObjectPostCreateHook(NamespaceRelationId, nspoid, 0);
return nspoid;
}
/*
* Test whether an object exists.
*/
static bool
object_exists(ObjectAddress address)
{
int cache = -1;
Oid indexoid = InvalidOid;
Relation rel;
ScanKeyData skey[1];
SysScanDesc sd;
bool found;
/* Sub-objects require special treatment. */
if (address.objectSubId != 0)
{
HeapTuple atttup;
/* Currently, attributes are the only sub-objects. */
Assert(address.classId == RelationRelationId);
atttup = SearchSysCache2(ATTNUM, ObjectIdGetDatum(address.objectId),
Int16GetDatum(address.objectSubId));
if (!HeapTupleIsValid(atttup))
found = false;
else
{
found = ((Form_pg_attribute) GETSTRUCT(atttup))->attisdropped;
ReleaseSysCache(atttup);
}
return found;
}
/*
* For object types that have a relevant syscache, we use it; for
* everything else, we'll have to do an index-scan. This switch
* sets either the cache to be used for the syscache lookup, or the
* index to be used for the index scan.
*/
switch (address.classId)
{
case RelationRelationId:
cache = RELOID;
break;
case RewriteRelationId:
indexoid = RewriteOidIndexId;
break;
case TriggerRelationId:
indexoid = TriggerOidIndexId;
break;
case ConstraintRelationId:
cache = CONSTROID;
break;
case DatabaseRelationId:
cache = DATABASEOID;
break;
case TableSpaceRelationId:
cache = TABLESPACEOID;
break;
case AuthIdRelationId:
cache = AUTHOID;
break;
case NamespaceRelationId:
cache = NAMESPACEOID;
break;
case LanguageRelationId:
cache = LANGOID;
break;
case TypeRelationId:
cache = TYPEOID;
break;
case ProcedureRelationId:
cache = PROCOID;
break;
case OperatorRelationId:
cache = OPEROID;
break;
case CollationRelationId:
cache = COLLOID;
break;
case ConversionRelationId:
cache = CONVOID;
break;
case OperatorClassRelationId:
cache = CLAOID;
break;
case OperatorFamilyRelationId:
cache = OPFAMILYOID;
break;
case LargeObjectRelationId:
/*
* Weird backward compatibility hack: ObjectAddress notation uses
* LargeObjectRelationId for large objects, but since PostgreSQL
* 9.0, the relevant catalog is actually
* LargeObjectMetadataRelationId.
*/
address.classId = LargeObjectMetadataRelationId;
indexoid = LargeObjectMetadataOidIndexId;
break;
case CastRelationId:
indexoid = CastOidIndexId;
break;
case ForeignDataWrapperRelationId:
cache = FOREIGNDATAWRAPPEROID;
break;
case ForeignServerRelationId:
cache = FOREIGNSERVEROID;
break;
case TSParserRelationId:
cache = TSPARSEROID;
break;
case TSDictionaryRelationId:
cache = TSDICTOID;
break;
case TSTemplateRelationId:
cache = TSTEMPLATEOID;
break;
case TSConfigRelationId:
cache = TSCONFIGOID;
break;
case ExtensionRelationId:
indexoid = ExtensionOidIndexId;
break;
default:
elog(ERROR, "unrecognized classid: %u", address.classId);
}
/* Found a syscache? */
if (cache != -1)
return SearchSysCacheExists1(cache, ObjectIdGetDatum(address.objectId));
/* No syscache, so examine the table directly. */
Assert(OidIsValid(indexoid));
ScanKeyInit(&skey[0],
ObjectIdAttributeNumber,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(address.objectId));
rel = heap_open(address.classId, AccessShareLock);
sd = systable_beginscan(rel, indexoid, true, SnapshotNow, 1, skey);
found = HeapTupleIsValid(systable_getnext(sd));
systable_endscan(sd);
heap_close(rel, AccessShareLock);
return found;
}