From a9f9ac7b471934399aae14938567239b10e60ed6 Mon Sep 17 00:00:00 2001 From: "okbob@github.com" Date: Mon, 4 Apr 2022 21:19:03 +0200 Subject: [PATCH 01/15] catalog support for session variables Implementation new system object class - session variable with new access rights SELECT, UPDATE, with routines for creating session variable, initialization of session variable from system catalog, and lookups routines for identification of session variables. --- src/backend/access/transam/xact.c | 11 + src/backend/catalog/Makefile | 4 +- src/backend/catalog/aclchk.c | 302 ++++++++++++++++ src/backend/catalog/dependency.c | 13 +- src/backend/catalog/meson.build | 1 + src/backend/catalog/namespace.c | 453 ++++++++++++++++++++++++ src/backend/catalog/objectaddress.c | 126 ++++++- src/backend/catalog/pg_shdepend.c | 2 + src/backend/catalog/pg_variable.c | 372 +++++++++++++++++++ src/backend/commands/Makefile | 1 + src/backend/commands/alter.c | 9 + src/backend/commands/dropcmds.c | 4 + src/backend/commands/event_trigger.c | 6 + src/backend/commands/seclabel.c | 1 + src/backend/commands/session_variable.c | 242 +++++++++++++ src/backend/commands/tablecmds.c | 45 ++- src/backend/parser/gram.y | 145 +++++++- src/backend/parser/parse_agg.c | 2 + src/backend/parser/parse_expr.c | 5 + src/backend/parser/parse_func.c | 1 + src/backend/parser/parse_utilcmd.c | 12 + src/backend/tcop/utility.c | 16 + src/backend/utils/adt/acl.c | 8 +- src/backend/utils/cache/lsyscache.c | 113 ++++++ src/backend/utils/cache/syscache.c | 23 ++ src/backend/utils/fmgr/fmgr.c | 6 +- src/include/catalog/dependency.h | 5 +- src/include/catalog/meson.build | 1 + src/include/catalog/namespace.h | 7 + src/include/catalog/pg_default_acl.h | 1 + src/include/catalog/pg_proc.dat | 3 + src/include/catalog/pg_variable.h | 120 +++++++ src/include/commands/session_variable.h | 41 +++ src/include/nodes/parsenodes.h | 20 ++ src/include/parser/kwlist.h | 2 + src/include/parser/parse_node.h | 1 + src/include/tcop/cmdtaglist.h | 3 + src/include/utils/acl.h | 6 +- src/include/utils/lsyscache.h | 9 + src/include/utils/syscache.h | 6 +- src/test/regress/expected/oidjoins.out | 4 + src/tools/pgindent/typedefs.list | 4 + 42 files changed, 2137 insertions(+), 19 deletions(-) create mode 100644 src/backend/catalog/pg_variable.c create mode 100644 src/backend/commands/session_variable.c create mode 100644 src/include/catalog/pg_variable.h create mode 100644 src/include/commands/session_variable.h diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index 883d6c0f703..6643739e53d 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -36,6 +36,7 @@ #include "catalog/pg_enum.h" #include "catalog/storage.h" #include "commands/async.h" +#include "commands/session_variable.h" #include "commands/tablecmds.h" #include "commands/trigger.h" #include "common/pg_prng.h" @@ -2213,6 +2214,9 @@ CommitTransaction(void) */ smgrDoPendingSyncs(true, is_parallel_worker); + /* Let ON COMMIT DROP */ + AtPreEOXact_SessionVariable_on_xact_actions(true); + /* close large objects before lower-level cleanup */ AtEOXact_LargeObject(true); @@ -2789,6 +2793,9 @@ AbortTransaction(void) AtAbort_Portals(); smgrDoPendingSyncs(false, is_parallel_worker); AtEOXact_LargeObject(false); + + /* 'false' means it's abort */ + AtPreEOXact_SessionVariable_on_xact_actions(false); AtAbort_Notify(); AtEOXact_RelationMap(false, is_parallel_worker); AtAbort_Twophase(); @@ -4996,6 +5003,8 @@ CommitSubTransaction(void) AtEOSubXact_SPI(true, s->subTransactionId); AtEOSubXact_on_commit_actions(true, s->subTransactionId, s->parent->subTransactionId); + AtEOSubXact_SessionVariable_on_xact_actions(true, s->subTransactionId, + s->parent->subTransactionId); AtEOSubXact_Namespace(true, s->subTransactionId, s->parent->subTransactionId); AtEOSubXact_Files(true, s->subTransactionId, @@ -5160,6 +5169,8 @@ AbortSubTransaction(void) AtEOSubXact_SPI(false, s->subTransactionId); AtEOSubXact_on_commit_actions(false, s->subTransactionId, s->parent->subTransactionId); + AtEOSubXact_SessionVariable_on_xact_actions(false, s->subTransactionId, + s->parent->subTransactionId); AtEOSubXact_Namespace(false, s->subTransactionId, s->parent->subTransactionId); AtEOSubXact_Files(false, s->subTransactionId, diff --git a/src/backend/catalog/Makefile b/src/backend/catalog/Makefile index 89a0221ec9b..f89e12eaf29 100644 --- a/src/backend/catalog/Makefile +++ b/src/backend/catalog/Makefile @@ -45,6 +45,7 @@ OBJS = \ pg_shdepend.o \ pg_subscription.o \ pg_type.o \ + pg_variable.o \ storage.o \ toasting.o @@ -72,7 +73,8 @@ CATALOG_HEADERS := \ pg_collation.h pg_parameter_acl.h pg_partitioned_table.h \ pg_range.h pg_transform.h \ pg_sequence.h pg_publication.h pg_publication_namespace.h \ - pg_publication_rel.h pg_subscription.h pg_subscription_rel.h + pg_publication_rel.h pg_subscription.h pg_subscription_rel.h \ + pg_variable.h GENERATED_HEADERS := $(CATALOG_HEADERS:%.h=%_d.h) schemapg.h system_fk_info.h diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c index aa5a2ed9483..11b2788529b 100644 --- a/src/backend/catalog/aclchk.c +++ b/src/backend/catalog/aclchk.c @@ -59,6 +59,7 @@ #include "catalog/pg_ts_parser.h" #include "catalog/pg_ts_template.h" #include "catalog/pg_type.h" +#include "catalog/pg_variable.h" #include "commands/dbcommands.h" #include "commands/defrem.h" #include "commands/event_trigger.h" @@ -115,6 +116,7 @@ static void ExecGrant_Namespace(InternalGrant *istmt); static void ExecGrant_Tablespace(InternalGrant *istmt); static void ExecGrant_Type(InternalGrant *istmt); static void ExecGrant_Parameter(InternalGrant *istmt); +static void ExecGrant_Variable(InternalGrant *istmt); static void SetDefaultACLsInSchemas(InternalDefaultACL *iacls, List *nspnames); static void SetDefaultACL(InternalDefaultACL *iacls); @@ -266,6 +268,9 @@ restrict_and_check_grant(bool is_grant, AclMode avail_goptions, bool all_privs, case OBJECT_PARAMETER_ACL: whole_mask = ACL_ALL_RIGHTS_PARAMETER_ACL; break; + case OBJECT_VARIABLE: + whole_mask = ACL_ALL_RIGHTS_VARIABLE; + break; default: elog(ERROR, "unrecognized object type: %d", objtype); /* not reached, but keep compiler quiet */ @@ -510,6 +515,10 @@ ExecuteGrantStmt(GrantStmt *stmt) all_privileges = ACL_ALL_RIGHTS_PARAMETER_ACL; errormsg = gettext_noop("invalid privilege type %s for parameter"); break; + case OBJECT_VARIABLE: + all_privileges = ACL_ALL_RIGHTS_VARIABLE; + errormsg = gettext_noop("invalid privilege type %s for session variable"); + break; default: elog(ERROR, "unrecognized GrantStmt.objtype: %d", (int) stmt->objtype); @@ -615,6 +624,9 @@ ExecGrantStmt_oids(InternalGrant *istmt) case OBJECT_PARAMETER_ACL: ExecGrant_Parameter(istmt); break; + case OBJECT_VARIABLE: + ExecGrant_Variable(istmt); + break; default: elog(ERROR, "unrecognized GrantStmt.objtype: %d", (int) istmt->objtype); @@ -805,6 +817,19 @@ objectNamesToOids(ObjectType objtype, List *objnames, bool is_grant) objects = lappend_oid(objects, parameterId); } break; + case OBJECT_VARIABLE: + foreach(cell, objnames) + { + RangeVar *varvar = (RangeVar *) lfirst(cell); + Oid relOid; + + relOid = LookupVariable(varvar->schemaname, + varvar->relname, + false, + false); + objects = lappend_oid(objects, relOid); + } + break; default: elog(ERROR, "unrecognized GrantStmt.objtype: %d", (int) objtype); @@ -894,6 +919,33 @@ objectsInSchemaToOids(ObjectType objtype, List *nspnames) table_close(rel, AccessShareLock); } break; + case OBJECT_VARIABLE: + { + ScanKeyData key; + Relation rel; + TableScanDesc scan; + HeapTuple tuple; + + ScanKeyInit(&key, + Anum_pg_variable_varnamespace, + BTEqualStrategyNumber, F_OIDEQ, + ObjectIdGetDatum(namespaceId)); + + rel = table_open(VariableRelationId, AccessShareLock); + scan = table_beginscan_catalog(rel, 1, &key); + + while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL) + { + Oid oid = ((Form_pg_proc) GETSTRUCT(tuple))->oid; + + objects = lappend_oid(objects, oid); + } + + table_endscan(scan); + table_close(rel, AccessShareLock); + } + break; + default: /* should not happen */ elog(ERROR, "unrecognized GrantStmt.objtype: %d", @@ -1053,6 +1105,10 @@ ExecAlterDefaultPrivilegesStmt(ParseState *pstate, AlterDefaultPrivilegesStmt *s all_privileges = ACL_ALL_RIGHTS_SCHEMA; errormsg = gettext_noop("invalid privilege type %s for schema"); break; + case OBJECT_VARIABLE: + all_privileges = ACL_ALL_RIGHTS_VARIABLE; + errormsg = gettext_noop("invalid privilege type %s for session variable"); + break; default: elog(ERROR, "unrecognized GrantStmt.objtype: %d", (int) action->objtype); @@ -1244,6 +1300,12 @@ SetDefaultACL(InternalDefaultACL *iacls) this_privileges = ACL_ALL_RIGHTS_SCHEMA; break; + case OBJECT_VARIABLE: + objtype = DEFACLOBJ_VARIABLE; + if (iacls->all_privs && this_privileges == ACL_NO_RIGHTS) + this_privileges = ACL_ALL_RIGHTS_VARIABLE; + break; + default: elog(ERROR, "unrecognized objtype: %d", (int) iacls->objtype); @@ -1475,6 +1537,9 @@ RemoveRoleFromObjectACL(Oid roleid, Oid classid, Oid objid) case DEFACLOBJ_NAMESPACE: iacls.objtype = OBJECT_SCHEMA; break; + case DEFACLOBJ_VARIABLE: + iacls.objtype = OBJECT_VARIABLE; + break; default: /* Shouldn't get here */ elog(ERROR, "unexpected default ACL type: %d", @@ -1535,6 +1600,9 @@ RemoveRoleFromObjectACL(Oid roleid, Oid classid, Oid objid) case ParameterAclRelationId: istmt.objtype = OBJECT_PARAMETER_ACL; break; + case VariableRelationId: + istmt.objtype = OBJECT_VARIABLE; + break; default: elog(ERROR, "unexpected object class %u", classid); break; @@ -3367,6 +3435,129 @@ ExecGrant_Parameter(InternalGrant *istmt) table_close(relation, RowExclusiveLock); } +static void +ExecGrant_Variable(InternalGrant *istmt) +{ + Relation relation; + ListCell *cell; + + if (istmt->all_privs && istmt->privileges == ACL_NO_RIGHTS) + istmt->privileges = ACL_ALL_RIGHTS_VARIABLE; + + relation = table_open(VariableRelationId, RowExclusiveLock); + + foreach(cell, istmt->objects) + { + Oid varId = lfirst_oid(cell); + Form_pg_variable pg_variable_tuple; + Datum aclDatum; + bool isNull; + AclMode avail_goptions; + AclMode this_privileges; + Acl *old_acl; + Acl *new_acl; + Oid grantorId; + Oid ownerId; + HeapTuple tuple; + HeapTuple newtuple; + Datum values[Natts_pg_variable]; + bool nulls[Natts_pg_variable]; + bool replaces[Natts_pg_variable]; + int noldmembers; + int nnewmembers; + Oid *oldmembers; + Oid *newmembers; + + tuple = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varId)); + if (!HeapTupleIsValid(tuple)) + elog(ERROR, "cache lookup failed for session variable %u", varId); + + pg_variable_tuple = (Form_pg_variable) GETSTRUCT(tuple); + + /* + * Get owner ID and working copy of existing ACL. If there's no ACL, + * substitute the proper default. + */ + ownerId = pg_variable_tuple->varowner; + aclDatum = SysCacheGetAttr(VARIABLEOID, tuple, Anum_pg_variable_varacl, + &isNull); + if (isNull) + { + old_acl = acldefault(OBJECT_VARIABLE, ownerId); + /* There are no old member roles according to the catalogs */ + noldmembers = 0; + oldmembers = NULL; + } + else + { + old_acl = DatumGetAclPCopy(aclDatum); + /* Get the roles mentioned in the existing ACL */ + noldmembers = aclmembers(old_acl, &oldmembers); + } + + /* Determine ID to do the grant as, and available grant options */ + select_best_grantor(GetUserId(), istmt->privileges, + old_acl, ownerId, + &grantorId, &avail_goptions); + + /* + * Restrict the privileges to what we can actually grant, and emit the + * standards-mandated warning and error messages. + */ + this_privileges = + restrict_and_check_grant(istmt->is_grant, avail_goptions, + istmt->all_privs, istmt->privileges, + varId, grantorId, OBJECT_VARIABLE, + NameStr(pg_variable_tuple->varname), + 0, NULL); + + /* + * Generate new ACL. + */ + new_acl = merge_acl_with_grant(old_acl, istmt->is_grant, + istmt->grant_option, istmt->behavior, + istmt->grantees, this_privileges, + grantorId, ownerId); + + /* + * We need the members of both old and new ACLs so we can correct the + * shared dependency information. + */ + nnewmembers = aclmembers(new_acl, &newmembers); + + /* finished building new ACL value, now insert it */ + MemSet(values, 0, sizeof(values)); + MemSet(nulls, false, sizeof(nulls)); + MemSet(replaces, false, sizeof(replaces)); + + replaces[Anum_pg_variable_varacl - 1] = true; + values[Anum_pg_variable_varacl - 1] = PointerGetDatum(new_acl); + + newtuple = heap_modify_tuple(tuple, RelationGetDescr(relation), values, + nulls, replaces); + + CatalogTupleUpdate(relation, &newtuple->t_self, newtuple); + + /* Update initial privileges for extensions */ + recordExtensionInitPriv(varId, VariableRelationId, 0, new_acl); + + /* Update the shared dependency ACL info */ + updateAclDependencies(VariableRelationId, varId, 0, + ownerId, + noldmembers, oldmembers, + nnewmembers, newmembers); + + ReleaseSysCache(tuple); + + pfree(new_acl); + + /* prevent error when processing duplicate objects */ + CommandCounterIncrement(); + } + + table_close(relation, RowExclusiveLock); +} + static AclMode string_to_privilege(const char *privname) @@ -3568,6 +3759,9 @@ aclcheck_error(AclResult aclerr, ObjectType objtype, case OBJECT_TYPE: msg = gettext_noop("permission denied for type %s"); break; + case OBJECT_VARIABLE: + msg = gettext_noop("permission denied for session variable %s"); + break; case OBJECT_VIEW: msg = gettext_noop("permission denied for view %s"); break; @@ -3679,6 +3873,9 @@ aclcheck_error(AclResult aclerr, ObjectType objtype, case OBJECT_TYPE: msg = gettext_noop("must be owner of type %s"); break; + case OBJECT_VARIABLE: + msg = gettext_noop("must be owner of session variable %s"); + break; case OBJECT_VIEW: msg = gettext_noop("must be owner of view %s"); break; @@ -3827,6 +4024,8 @@ pg_aclmask(ObjectType objtype, Oid table_oid, AttrNumber attnum, Oid roleid, return ACL_NO_RIGHTS; case OBJECT_TYPE: return pg_type_aclmask(table_oid, roleid, mask, how); + case OBJECT_VARIABLE: + return pg_variable_aclmask(table_oid, roleid, mask, how); default: elog(ERROR, "unrecognized objtype: %d", (int) objtype); @@ -4810,6 +5009,66 @@ pg_type_aclmask(Oid type_oid, Oid roleid, AclMode mask, AclMaskHow how) return result; } +/* + * Exported routine for examining a user's privileges for a variable. + */ +AclMode +pg_variable_aclmask(Oid var_oid, Oid roleid, AclMode mask, AclMaskHow how) +{ + AclMode result; + HeapTuple tuple; + Datum aclDatum; + bool isNull; + Acl *acl; + Oid ownerId; + + Form_pg_variable varForm; + + /* Bypass permission checks for superusers */ + if (superuser_arg(roleid)) + return mask; + + /* + * Must get the variables's tuple from pg_variable + */ + tuple = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(var_oid)); + if (!HeapTupleIsValid(tuple)) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("variable with OID %u does not exist", + var_oid))); + varForm = (Form_pg_variable) GETSTRUCT(tuple); + + /* + * Now get the variable's owner and ACL from the tuple + */ + ownerId = varForm->varowner; + + aclDatum = SysCacheGetAttr(VARIABLEOID, tuple, + Anum_pg_variable_varacl, &isNull); + if (isNull) + { + /* No ACL, so build default ACL */ + acl = acldefault(OBJECT_VARIABLE, ownerId); + aclDatum = (Datum) 0; + } + else + { + /* detoast rel's ACL if necessary */ + acl = DatumGetAclP(aclDatum); + } + + result = aclmask(acl, roleid, ownerId, mask, how); + + /* if we have a detoasted copy, free it */ + if (acl && (Pointer) acl != DatumGetPointer(aclDatum)) + pfree(acl); + + ReleaseSysCache(tuple); + + return result; +} + /* * Exported routine for checking a user's access privileges to a column * @@ -5110,6 +5369,18 @@ pg_type_aclcheck(Oid type_oid, Oid roleid, AclMode mode) return ACLCHECK_NO_PRIV; } +/* + * Exported routine for checking a user's access privileges to a variable + */ +AclResult +pg_variable_aclcheck(Oid var_oid, Oid roleid, AclMode mode) +{ + if (pg_variable_aclmask(var_oid, roleid, mode, ACLMASK_ANY) != 0) + return ACLCHECK_OK; + else + return ACLCHECK_NO_PRIV; +} + /* * Ownership check for a relation (specified by OID). */ @@ -5727,6 +5998,33 @@ pg_statistics_object_ownercheck(Oid stat_oid, Oid roleid) return has_privs_of_role(roleid, ownerId); } +/* + * Ownership check for a session variable (specified by OID). + */ +bool +pg_variable_ownercheck(Oid db_oid, Oid roleid) +{ + HeapTuple tuple; + Oid ownerId; + + /* Superusers bypass all permission checking. */ + if (superuser_arg(roleid)) + return true; + + tuple = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(db_oid)); + if (!HeapTupleIsValid(tuple)) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_DATABASE), + errmsg("session variable with OID %u does not exist", db_oid))); + + ownerId = ((Form_pg_variable) GETSTRUCT(tuple))->varowner; + + ReleaseSysCache(tuple); + + return has_privs_of_role(roleid, ownerId); +} + + /* * Check whether specified role has CREATEROLE privilege (or is a superuser) * @@ -5855,6 +6153,10 @@ get_user_default_acl(ObjectType objtype, Oid ownerId, Oid nsp_oid) defaclobjtype = DEFACLOBJ_NAMESPACE; break; + case OBJECT_VARIABLE: + defaclobjtype = DEFACLOBJ_VARIABLE; + break; + default: return NULL; } diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c index 7f3e64b5ae6..731b9805adb 100644 --- a/src/backend/catalog/dependency.c +++ b/src/backend/catalog/dependency.c @@ -65,12 +65,15 @@ #include "catalog/pg_ts_template.h" #include "catalog/pg_type.h" #include "catalog/pg_user_mapping.h" +#include "catalog/pg_variable.h" #include "commands/comment.h" #include "commands/defrem.h" #include "commands/event_trigger.h" #include "commands/extension.h" #include "commands/policy.h" #include "commands/publicationcmds.h" +#include "commands/schemacmds.h" +#include "commands/session_variable.h" #include "commands/seclabel.h" #include "commands/sequence.h" #include "commands/trigger.h" @@ -188,7 +191,8 @@ static const Oid object_classes[] = { PublicationRelationId, /* OCLASS_PUBLICATION */ PublicationRelRelationId, /* OCLASS_PUBLICATION_REL */ SubscriptionRelationId, /* OCLASS_SUBSCRIPTION */ - TransformRelationId /* OCLASS_TRANSFORM */ + TransformRelationId, /* OCLASS_TRANSFORM */ + VariableRelationId /* OCLASS_VARIABLE */ }; @@ -1508,6 +1512,10 @@ doDeletion(const ObjectAddress *object, int flags) DropObjectById(object); break; + case OCLASS_VARIABLE: + DropVariable(object->objectId); + break; + /* * These global object types are not supported here. */ @@ -2966,6 +2974,9 @@ getObjectClass(const ObjectAddress *object) case TransformRelationId: return OCLASS_TRANSFORM; + + case VariableRelationId: + return OCLASS_VARIABLE; } /* shouldn't get here */ diff --git a/src/backend/catalog/meson.build b/src/backend/catalog/meson.build index 08747914516..27306e35928 100644 --- a/src/backend/catalog/meson.build +++ b/src/backend/catalog/meson.build @@ -30,6 +30,7 @@ backend_sources += files( 'pg_shdepend.c', 'pg_subscription.c', 'pg_type.c', + 'pg_variable.c', 'storage.c', 'toasting.c', ) diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c index 539df1da949..1a9c92b3a8c 100644 --- a/src/backend/catalog/namespace.c +++ b/src/backend/catalog/namespace.c @@ -39,6 +39,7 @@ #include "catalog/pg_ts_parser.h" #include "catalog/pg_ts_template.h" #include "catalog/pg_type.h" +#include "catalog/pg_variable.h" #include "commands/dbcommands.h" #include "funcapi.h" #include "mb/pg_wchar.h" @@ -764,6 +765,69 @@ RelationIsVisible(Oid relid) return visible; } +/* + * VariableIsVisible + * Determine whether a variable (identified by OID) is visible in the + * current search path. Visible means "would be found by searching + * for the unqualified variable name". + */ +bool +VariableIsVisible(Oid varid) +{ + HeapTuple vartup; + Form_pg_variable varform; + Oid varnamespace; + bool visible; + + vartup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + if (!HeapTupleIsValid(vartup)) + elog(ERROR, "cache lookup failed for session variable %u", varid); + varform = (Form_pg_variable) GETSTRUCT(vartup); + + recomputeNamespacePath(); + + /* + * Quick check: if it ain't in the path at all, it ain't visible. Items in + * the system namespace are surely in the path and so we needn't even do + * list_member_oid() for them. + */ + varnamespace = varform->varnamespace; + if (varnamespace != PG_CATALOG_NAMESPACE && + !list_member_oid(activeSearchPath, varnamespace)) + visible = false; + else + { + /* + * If it is in the path, it might still not be visible; it could be + * hidden by another variable of the same name earlier in the path. So + * we must do a slow check for conflicting relations. + */ + char *varname = NameStr(varform->varname); + ListCell *l; + + visible = false; + foreach(l, activeSearchPath) + { + Oid namespaceId = lfirst_oid(l); + + if (namespaceId == varnamespace) + { + /* Found it first in path */ + visible = true; + break; + } + if (OidIsValid(get_varname_varid(varname, namespaceId))) + { + /* Found something else first in path */ + break; + } + } + } + + ReleaseSysCache(vartup); + + return visible; +} /* * TypenameGetTypid @@ -2839,6 +2903,384 @@ TSConfigIsVisible(Oid cfgid) return visible; } +/* + * Returns oid of session variable specified by possibly qualified identifier. + * + * If not found, returns InvalidOid if missing_ok, else throws error. + * When rowtype_only argument is true the session variables of not + * composite types are ignored. This should to reduce possible collisions. + */ +Oid +LookupVariable(const char *nspname, + const char *varname, + bool rowtype_only, + bool missing_ok) +{ + Oid namespaceId; + Oid varoid = InvalidOid; + ListCell *l; + + if (nspname) + { + namespaceId = LookupExplicitNamespace(nspname, missing_ok); + + /* + * If nspname is not a known namespace, then nspname.varname cannot be + * any usable session variable. + */ + if (OidIsValid(namespaceId)) + { + varoid = GetSysCacheOid2(VARIABLENAMENSP, Anum_pg_variable_oid, + PointerGetDatum(varname), + ObjectIdGetDatum(namespaceId)); + + if (OidIsValid(varoid)) + { + if (rowtype_only && !type_is_rowtype(get_session_variable_type(varoid))) + varoid = InvalidOid; + } + } + } + else + { + /* Iterate over schemas in search_path */ + recomputeNamespacePath(); + + foreach(l, activeSearchPath) + { + namespaceId = lfirst_oid(l); + + varoid = GetSysCacheOid2(VARIABLENAMENSP, Anum_pg_variable_oid, + PointerGetDatum(varname), + ObjectIdGetDatum(namespaceId)); + + if (OidIsValid(varoid)) + { + if (rowtype_only) + { + if (!type_is_rowtype(get_session_variable_type(varoid))) + { + varoid = InvalidOid; + continue; + } + } + + break; + } + } + } + + if (!OidIsValid(varoid) && !missing_ok) + { + if (nspname) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("session variable \"%s.%s\" does not exist", + nspname, varname))); + else + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("session variable \"%s\" does not exist", + varname))); + } + + return varoid; +} + +/* + * The input list contains names with indirection expressions used as the left + * part of LET statement. The following routine returns a new list with only + * initial strings (names) - without indirection expressions. + */ +List * +NamesFromList(List *names) +{ + ListCell *l; + List *result = NIL; + + foreach(l, names) + { + Node *n = lfirst(l); + + if (IsA(n, String)) + { + result = lappend(result, n); + } + else + break; + } + + return result; +} + +/* + * IdentifyVariable - try to find variable identified by list of names. + * + * Before this call we don't know, how these fields should be mapped to + * schema name, variable name and attribute name. In this routine + * we try to apply passed names to all possible combinations of schema name, + * variable name and attribute name, and we count valid combinations. + * + * Returns oid of identified variable. When last field of names list is + * identified as an attribute, then output attrname argument is set to + * an string of this field. + * + * When there is not any valid combination, then we are sure, so the + * list of names cannot to identify any session variable. In this case + * we return InvalidOid. + * + * We can find more valid combination than one. + * Example: users can have session variable x in schema y, and + * session variable y with attribute x inside some schema from + * search path. In this situation the meaning of expression "y"."x" + * is ambiguous. In this case this routine returns oid of variable + * x in schema y, and the output parameter "not_unique" is set to + * true. In this case this variable is locked. + * + * The AccessShareLock is created on related session variable. The lock + * will be kept for the whole transaction. + * + * Note: the out attrname should be used only when the session variable + * is identified. When the session variable is not identified, then this + * output variable can hold reference to some string, but isn't sure + * about its semantics. + */ +Oid +IdentifyVariable(List *names, char **attrname, bool *not_unique) +{ + Node *field1 = NULL; + Node *field2 = NULL; + Node *field3 = NULL; + Node *field4 = NULL; + char *a = NULL; + char *b = NULL; + char *c = NULL; + char *d = NULL; + Oid varid = InvalidOid; + Oid old_varid = InvalidOid; + uint64 inval_count; + bool retry = false; + + /* + * DDL operations can change the results of a name lookup. Since all such + * operations will generate invalidation messages, we keep track of + * whether any such messages show up while we're performing the operation, + * and retry until either (1) no more invalidation messages show up or (2) + * the answer doesn't change. + */ + for (;;) + { + Oid varoid_without_attr = InvalidOid; + Oid varoid_with_attr = InvalidOid; + + *not_unique = false; + *attrname = NULL; + varid = InvalidOid; + + inval_count = SharedInvalidMessageCounter; + + switch (list_length(names)) + { + case 1: + field1 = linitial(names); + + Assert(IsA(field1, String)); + + varid = LookupVariable(NULL, strVal(field1), false, true); + break; + + case 2: + field1 = linitial(names); + field2 = lsecond(names); + + Assert(IsA(field1, String)); + a = strVal(field1); + + if (IsA(field2, String)) + { + b = strVal(field2); + + /* + * a.b can mean "schema"."variable" or "variable"."field", + * Check both variants, and returns InvalidOid with + * not_unique flag, when both interpretations are + * possible. Second node can be star. In this case, the + * only allowed possibility is "variable"."*". + */ + varoid_without_attr = LookupVariable(a, b, false, true); + varoid_with_attr = LookupVariable(NULL, a, true, true); + } + else + { + /* + * Session variables doesn't support unboxing by star + * syntax. But this syntax have to be calculated here, + * because can come from non session variables related + * expressions. + */ + Assert(IsA(field2, A_Star)); + break; + } + + if (OidIsValid(varoid_without_attr) && OidIsValid(varoid_with_attr)) + { + *not_unique = true; + varid = varoid_without_attr; + } + else if (OidIsValid(varoid_without_attr)) + { + varid = varoid_without_attr; + } + else if (OidIsValid(varoid_with_attr)) + { + *attrname = b; + varid = varoid_with_attr; + } + break; + + case 3: + field1 = linitial(names); + field2 = lsecond(names); + field3 = lthird(names); + + Assert(IsA(field1, String)); + Assert(IsA(field2, String)); + + a = strVal(field1); + b = strVal(field2); + + if (IsA(field3, String)) + { + c = strVal(field3); + + /* + * a.b.c can mean "catalog"."schema"."variable" or + * "schema"."variable"."field", Check both variants, and + * returns InvalidOid with not_unique flag, when both + * interpretations are possible. When third node is star, + * the only possible interpretation is + * "schema"."variable"."*". + */ + varoid_without_attr = LookupVariable(b, c, false, true); + varoid_with_attr = LookupVariable(a, b, true, true); + } + else + { + Assert(IsA(field3, A_Star)); + break; + } + + if (OidIsValid(varoid_without_attr) && OidIsValid(varoid_with_attr)) + { + *not_unique = true; + varid = varoid_without_attr; + } + else if (OidIsValid(varoid_without_attr)) + { + + /* + * In this case, "a" is used as catalog name - check it. + */ + if (strcmp(a, get_database_name(MyDatabaseId)) != 0) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cross-database references are not implemented: %s", + NameListToString(names)))); + + varid = varoid_without_attr; + } + else if (OidIsValid(varoid_with_attr)) + { + *attrname = c; + varid = varoid_with_attr; + } + break; + + case 4: + field1 = linitial(names); + field2 = lsecond(names); + field3 = lthird(names); + field4 = lfourth(names); + + Assert(IsA(field1, String)); + Assert(IsA(field2, String)); + Assert(IsA(field3, String)); + + a = strVal(field1); + b = strVal(field2); + c = strVal(field3); + + /* + * In this case, "a" is used as catalog name - check it. + */ + if (strcmp(a, get_database_name(MyDatabaseId)) != 0) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cross-database references are not implemented: %s", + NameListToString(names)))); + + if (IsA(field4, String)) + { + d = strVal(field4); + } + else + { + Assert(IsA(field4, A_Star)); + return InvalidOid; + } + + *attrname = d; + varid = LookupVariable(b, c, true, true); + break; + + default: + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("improper qualified name (too many dotted names): %s", + NameListToString(names)))); + break; + } + + /* + * If, upon retry, we get back the same OID we did last time, then the + * invalidation messages we processed did not change the final answer. + * So we're done. + * + * If we got a different OID, we've locked the variable that used to + * have this name rather than the one that does now. So release the + * lock. + */ + if (retry) + { + if (old_varid == varid) + break; + + if (OidIsValid(old_varid)) + UnlockDatabaseObject(VariableRelationId, old_varid, 0, AccessShareLock); + } + + /* + * Lock the variable. This will also accept any pending invalidation + * messages. If we got back InvalidOid, indicating not found, then + * there's nothing to lock, but we accept invalidation messages + * anyway, to flush any negative catcache entries that may be + * lingering. + */ + if (!OidIsValid(varid)) + AcceptInvalidationMessages(); + else if (OidIsValid(varid)) + LockDatabaseObject(VariableRelationId, varid, 0, AccessShareLock); + + if (inval_count == SharedInvalidMessageCounter) + break; + + retry = true; + old_varid = varid; + varid = InvalidOid; + } + + return varid; +} /* * DeconstructQualifiedName @@ -4656,3 +5098,14 @@ pg_is_other_temp_schema(PG_FUNCTION_ARGS) PG_RETURN_BOOL(isOtherTempNamespace(oid)); } + +Datum +pg_variable_is_visible(PG_FUNCTION_ARGS) +{ + Oid oid = PG_GETARG_OID(0); + + if (!SearchSysCacheExists1(VARIABLEOID, ObjectIdGetDatum(oid))) + PG_RETURN_NULL(); + + PG_RETURN_BOOL(VariableIsVisible(oid)); +} diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c index 284ca55469e..26f557eb470 100644 --- a/src/backend/catalog/objectaddress.c +++ b/src/backend/catalog/objectaddress.c @@ -64,6 +64,7 @@ #include "catalog/pg_ts_template.h" #include "catalog/pg_type.h" #include "catalog/pg_user_mapping.h" +#include "catalog/pg_variable.h" #include "commands/dbcommands.h" #include "commands/defrem.h" #include "commands/event_trigger.h" @@ -633,6 +634,20 @@ static const ObjectPropertyType ObjectProperty[] = OBJECT_USER_MAPPING, false }, + { + "session variable", + VariableRelationId, + VariableObjectIndexId, + VARIABLEOID, + VARIABLENAMENSP, + Anum_pg_variable_oid, + Anum_pg_variable_varname, + Anum_pg_variable_varnamespace, + Anum_pg_variable_varowner, + Anum_pg_variable_varacl, + OBJECT_VARIABLE, + true + } }; /* @@ -869,6 +884,10 @@ static const struct object_type_map /* OCLASS_STATISTIC_EXT */ { "statistics object", OBJECT_STATISTIC_EXT + }, + /* OCLASS_VARIABLE */ + { + "session variable", OBJECT_VARIABLE } }; @@ -894,6 +913,7 @@ static ObjectAddress get_object_address_attrdef(ObjectType objtype, bool missing_ok); static ObjectAddress get_object_address_type(ObjectType objtype, TypeName *typename, bool missing_ok); +static ObjectAddress get_object_address_variable(List *object, bool missing_ok); static ObjectAddress get_object_address_opcf(ObjectType objtype, List *object, bool missing_ok); static ObjectAddress get_object_address_opf_member(ObjectType objtype, @@ -1163,6 +1183,9 @@ get_object_address(ObjectType objtype, Node *object, missing_ok); address.objectSubId = 0; break; + case OBJECT_VARIABLE: + address = get_object_address_variable(castNode(List, object), missing_ok); + break; default: elog(ERROR, "unrecognized objtype: %d", (int) objtype); /* placate compiler, in case it thinks elog might return */ @@ -2039,16 +2062,20 @@ get_object_address_defacl(List *object, bool missing_ok) case DEFACLOBJ_NAMESPACE: objtype_str = "schemas"; break; + case DEFACLOBJ_VARIABLE: + objtype_str = "variables"; + break; default: ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("unrecognized default ACL object type \"%c\"", objtype), - errhint("Valid object types are \"%c\", \"%c\", \"%c\", \"%c\", \"%c\".", + errhint("Valid object types are \"%c\", \"%c\", \"%c\", \"%c\", \"%c\", \"%c\".", DEFACLOBJ_RELATION, DEFACLOBJ_SEQUENCE, DEFACLOBJ_FUNCTION, DEFACLOBJ_TYPE, - DEFACLOBJ_NAMESPACE))); + DEFACLOBJ_NAMESPACE, + DEFACLOBJ_VARIABLE))); } /* @@ -2132,6 +2159,24 @@ textarray_to_strvaluelist(ArrayType *arr) return list; } +/* + * Find the ObjectAddress for a session variable + */ +static ObjectAddress +get_object_address_variable(List *object, bool missing_ok) +{ + ObjectAddress address; + char *nspname = NULL; + char *varname = NULL; + + ObjectAddressSet(address, VariableRelationId, InvalidOid); + + DeconstructQualifiedName(object, &nspname, &varname); + address.objectId = LookupVariable(nspname, varname, false, missing_ok); + + return address; +} + /* * SQL-callable version of get_object_address */ @@ -2325,6 +2370,7 @@ pg_get_object_address(PG_FUNCTION_ARGS) case OBJECT_TABCONSTRAINT: case OBJECT_OPCLASS: case OBJECT_OPFAMILY: + case OBJECT_VARIABLE: objnode = (Node *) name; break; case OBJECT_ACCESS_METHOD: @@ -2635,6 +2681,11 @@ check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address, aclcheck_error(ACLCHECK_NOT_OWNER, objtype, NameListToString(castNode(List, object))); break; + case OBJECT_VARIABLE: + if (!pg_variable_ownercheck(address.objectId, roleid)) + aclcheck_error(ACLCHECK_NOT_OWNER, objtype, + NameListToString(castNode(List, object))); + break; default: elog(ERROR, "unrecognized object type: %d", (int) objtype); @@ -3536,6 +3587,32 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok) break; } + case OCLASS_VARIABLE: + { + char *nspname; + HeapTuple tup; + Form_pg_variable varform; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(object->objectId)); + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", + object->objectId); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + if (VariableIsVisible(object->objectId)) + nspname = NULL; + else + nspname = get_namespace_name(varform->varnamespace); + + appendStringInfo(&buffer, _("session variable %s"), + quote_qualified_identifier(nspname, + NameStr(varform->varname))); + + ReleaseSysCache(tup); + break; + } + case OCLASS_TSPARSER: { HeapTuple tup; @@ -3888,6 +3965,16 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok) _("default privileges on new schemas belonging to role %s"), rolename); break; + case DEFACLOBJ_VARIABLE: + if (nspname) + appendStringInfo(&buffer, + _("default privileges on new session variables belonging to role %s in schema %s"), + rolename, nspname); + else + appendStringInfo(&buffer, + _("default privileges on new session variables belonging to role %s"), + rolename); + break; default: /* shouldn't get here */ if (nspname) @@ -4664,6 +4751,10 @@ getObjectTypeDescription(const ObjectAddress *object, bool missing_ok) appendStringInfoString(&buffer, "transform"); break; + case OCLASS_VARIABLE: + appendStringInfoString(&buffer, "session variable"); + break; + /* * There's intentionally no default: case here; we want the * compiler to warn if a new OCLASS hasn't been handled above. @@ -5771,6 +5862,10 @@ getObjectIdentityParts(const ObjectAddress *object, appendStringInfoString(&buffer, " on schemas"); break; + case DEFACLOBJ_VARIABLE: + appendStringInfoString(&buffer, + " on session variables"); + break; } if (objname) @@ -6014,6 +6109,33 @@ getObjectIdentityParts(const ObjectAddress *object, } break; + case OCLASS_VARIABLE: + { + char *schema; + char *varname; + HeapTuple tup; + Form_pg_variable varform; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(object->objectId)); + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", + object->objectId); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + schema = get_namespace_name_or_temp(varform->varnamespace); + varname = NameStr(varform->varname); + + appendStringInfo(&buffer, "%s", + quote_qualified_identifier(schema, varname)); + + if (objname) + *objname = list_make2(schema, varname); + + ReleaseSysCache(tup); + break; + } + /* * There's intentionally no default: case here; we want the * compiler to warn if a new OCLASS hasn't been handled above. diff --git a/src/backend/catalog/pg_shdepend.c b/src/backend/catalog/pg_shdepend.c index bc26bf1ef5a..d18e859db57 100644 --- a/src/backend/catalog/pg_shdepend.c +++ b/src/backend/catalog/pg_shdepend.c @@ -47,6 +47,7 @@ #include "catalog/pg_ts_dict.h" #include "catalog/pg_type.h" #include "catalog/pg_user_mapping.h" +#include "catalog/pg_variable.h" #include "commands/alter.h" #include "commands/collationcmds.h" #include "commands/conversioncmds.h" @@ -1613,6 +1614,7 @@ shdepReassignOwned(List *roleids, Oid newrole) case DatabaseRelationId: case TSConfigRelationId: case TSDictionaryRelationId: + case VariableRelationId: { Oid classId = sdepForm->classid; Relation catalog; diff --git a/src/backend/catalog/pg_variable.c b/src/backend/catalog/pg_variable.c new file mode 100644 index 00000000000..973d8fd7d02 --- /dev/null +++ b/src/backend/catalog/pg_variable.c @@ -0,0 +1,372 @@ +/*------------------------------------------------------------------------- + * + * pg_variable.c + * session variables + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/backend/catalog/pg_variable.c + * + *------------------------------------------------------------------------- + */ + +#include "postgres.h" + +#include "access/heapam.h" +#include "access/htup_details.h" +#include "catalog/catalog.h" +#include "catalog/dependency.h" +#include "catalog/indexing.h" +#include "catalog/namespace.h" +#include "catalog/objectaccess.h" +#include "catalog/pg_collation.h" +#include "catalog/pg_namespace.h" +#include "catalog/pg_type.h" +#include "catalog/pg_variable.h" +#include "commands/session_variable.h" +#include "miscadmin.h" +#include "parser/parse_coerce.h" +#include "parser/parse_collate.h" +#include "parser/parse_expr.h" +#include "parser/parse_type.h" +#include "storage/lmgr.h" +#include "utils/builtins.h" +#include "utils/lsyscache.h" +#include "utils/pg_lsn.h" +#include "utils/syscache.h" + + +static ObjectAddress create_variable(const char *varName, + Oid varNamespace, + Oid varType, + int32 varTypmod, + Oid varOwner, + Oid varCollation, + Node *varDefexpr, + VariableEOXAction eoxaction, + bool is_not_null, + bool if_not_exists, + bool is_immutable); + + +/* + * Creates entry in pg_variable table + */ +static ObjectAddress +create_variable(const char *varName, + Oid varNamespace, + Oid varType, + int32 varTypmod, + Oid varOwner, + Oid varCollation, + Node *varDefexpr, + VariableEOXAction eoxaction, + bool is_not_null, + bool if_not_exists, + bool is_immutable) +{ + Acl *varacl; + NameData varname; + bool nulls[Natts_pg_variable]; + Datum values[Natts_pg_variable]; + Relation rel; + HeapTuple tup; + TupleDesc tupdesc; + ObjectAddress myself, + referenced; + ObjectAddresses *addrs; + Oid varid; + + Assert(varName); + Assert(OidIsValid(varNamespace)); + Assert(OidIsValid(varType)); + Assert(OidIsValid(varOwner)); + + rel = table_open(VariableRelationId, RowExclusiveLock); + + /* + * Check for duplicates. Note that this does not really prevent + * duplicates, it's here just to provide nicer error message in common + * case. The real protection is the unique key on the catalog. + */ + if (SearchSysCacheExists2(VARIABLENAMENSP, + PointerGetDatum(varName), + ObjectIdGetDatum(varNamespace))) + { + if (if_not_exists) + ereport(NOTICE, + (errcode(ERRCODE_DUPLICATE_OBJECT), + errmsg("session variable \"%s\" already exists, skipping", + varName))); + else + ereport(ERROR, + (errcode(ERRCODE_DUPLICATE_OBJECT), + errmsg("session variable \"%s\" already exists", + varName))); + + table_close(rel, RowExclusiveLock); + + return InvalidObjectAddress; + } + + memset(values, 0, sizeof(values)); + memset(nulls, false, sizeof(nulls)); + + namestrcpy(&varname, varName); + + varid = GetNewOidWithIndex(rel, VariableObjectIndexId, Anum_pg_variable_oid); + + values[Anum_pg_variable_oid - 1] = ObjectIdGetDatum(varid); + values[Anum_pg_variable_create_lsn - 1] = LSNGetDatum(GetXLogInsertRecPtr()); + values[Anum_pg_variable_varname - 1] = NameGetDatum(&varname); + values[Anum_pg_variable_varnamespace - 1] = ObjectIdGetDatum(varNamespace); + values[Anum_pg_variable_vartype - 1] = ObjectIdGetDatum(varType); + values[Anum_pg_variable_vartypmod - 1] = Int32GetDatum(varTypmod); + values[Anum_pg_variable_varowner - 1] = ObjectIdGetDatum(varOwner); + values[Anum_pg_variable_varcollation - 1] = ObjectIdGetDatum(varCollation); + values[Anum_pg_variable_varisnotnull - 1] = BoolGetDatum(is_not_null); + values[Anum_pg_variable_varisimmutable - 1] = BoolGetDatum(is_immutable); + values[Anum_pg_variable_vareoxaction - 1] = CharGetDatum(eoxaction); + + /* varacl will be determined later */ + + if (varDefexpr) + values[Anum_pg_variable_vardefexpr - 1] = CStringGetTextDatum(nodeToString(varDefexpr)); + else + nulls[Anum_pg_variable_vardefexpr - 1] = true; + + tupdesc = RelationGetDescr(rel); + + varacl = get_user_default_acl(OBJECT_VARIABLE, varOwner, + varNamespace); + + if (varacl != NULL) + values[Anum_pg_variable_varacl - 1] = PointerGetDatum(varacl); + else + nulls[Anum_pg_variable_varacl - 1] = true; + + tup = heap_form_tuple(tupdesc, values, nulls); + CatalogTupleInsert(rel, tup); + Assert(OidIsValid(varid)); + + addrs = new_object_addresses(); + + ObjectAddressSet(myself, VariableRelationId, varid); + + /* dependency on namespace */ + ObjectAddressSet(referenced, NamespaceRelationId, varNamespace); + add_exact_object_address(&referenced, addrs); + + /* dependency on used type */ + ObjectAddressSet(referenced, TypeRelationId, varType); + add_exact_object_address(&referenced, addrs); + + /* dependency on collation */ + if (OidIsValid(varCollation) && + varCollation != DEFAULT_COLLATION_OID) + { + ObjectAddressSet(referenced, CollationRelationId, varCollation); + add_exact_object_address(&referenced, addrs); + } + + /* dependency on default expr */ + if (varDefexpr) + recordDependencyOnExpr(&myself, (Node *) varDefexpr, + NIL, DEPENDENCY_NORMAL); + + record_object_address_dependencies(&myself, addrs, DEPENDENCY_NORMAL); + free_object_addresses(addrs); + + /* dependency on owner */ + recordDependencyOnOwner(VariableRelationId, varid, varOwner); + + /* dependencies on roles mentioned in default ACL */ + recordDependencyOnNewAcl(VariableRelationId, varid, 0, varOwner, varacl); + + /* dependency on extension */ + recordDependencyOnCurrentExtension(&myself, false); + + heap_freetuple(tup); + + /* Post creation hook for new function */ + InvokeObjectPostCreateHook(VariableRelationId, varid, 0); + + table_close(rel, RowExclusiveLock); + + return myself; +} + +/* + * Creates a new variable + * + * Used by CREATE VARIABLE command + */ +ObjectAddress +CreateVariable(ParseState *pstate, CreateSessionVarStmt *stmt) +{ + Oid namespaceid; + AclResult aclresult; + Oid typid; + int32 typmod; + Oid varowner = GetUserId(); + Oid collation; + Oid typcollation; + ObjectAddress variable; + + Node *cooked_default = NULL; + + /* + * Check consistency of arguments + */ + if (stmt->eoxaction == VARIABLE_EOX_DROP + && stmt->variable->relpersistence != RELPERSISTENCE_TEMP) + ereport(ERROR, + (errcode(ERRCODE_INVALID_OBJECT_DEFINITION), + errmsg("ON COMMIT DROP can only be used on temporary variables"))); + + if (stmt->is_not_null && stmt->is_immutable && !stmt->defexpr) + ereport(ERROR, + (errcode(ERRCODE_INVALID_OBJECT_DEFINITION), + errmsg("IMMUTABLE NOT NULL variable requires default expression"))); + + namespaceid = + RangeVarGetAndCheckCreationNamespace(stmt->variable, NoLock, NULL); + + typenameTypeIdAndMod(pstate, stmt->typeName, &typid, &typmod); + typcollation = get_typcollation(typid); + + aclresult = pg_type_aclcheck(typid, GetUserId(), ACL_USAGE); + if (aclresult != ACLCHECK_OK) + aclcheck_error_type(aclresult, typid); + + if (stmt->collClause) + collation = LookupCollation(pstate, + stmt->collClause->collname, + stmt->collClause->location); + else + collation = typcollation;; + + /* Complain if COLLATE is applied to an uncollatable type */ + if (OidIsValid(collation) && !OidIsValid(typcollation)) + ereport(ERROR, + (errcode(ERRCODE_DATATYPE_MISMATCH), + errmsg("collations are not supported by type %s", + format_type_be(typid)), + parser_errposition(pstate, stmt->collClause->location))); + + if (stmt->defexpr) + { + cooked_default = transformExpr(pstate, stmt->defexpr, + EXPR_KIND_VARIABLE_DEFAULT); + + cooked_default = coerce_to_specific_type(pstate, + cooked_default, typid, "DEFAULT"); + assign_expr_collations(pstate, cooked_default); + } + + variable = create_variable(stmt->variable->relname, + namespaceid, + typid, + typmod, + varowner, + collation, + cooked_default, + stmt->eoxaction, + stmt->is_not_null, + stmt->if_not_exists, + stmt->is_immutable); + + elog(DEBUG1, "record for session variable \"%s\" (oid:%d) was created in pg_variable", + stmt->variable->relname, variable.objectId); + + /* We want SessionVariableCreatePostprocess to see the catalog changes. */ + CommandCounterIncrement(); + + SessionVariableCreatePostprocess(variable.objectId, stmt->eoxaction); + + return variable; +} + +/* + * Drop variable by OID, and register the needed session variable + * cleanup. + */ +void +DropVariable(Oid varid) +{ + Relation rel; + HeapTuple tup; + + rel = table_open(VariableRelationId, RowExclusiveLock); + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for variable %u", varid); + + CatalogTupleDelete(rel, &tup->t_self); + + ReleaseSysCache(tup); + + table_close(rel, RowExclusiveLock); + + /* Do the necessary cleanup if needed in local memory */ + SessionVariableDropPostprocess(varid); +} + +/* + * Fetch attributes (without acl) of session variable from the syscache. + * We don't work with acl directly, so we don't need to read it here. + * Skip deserialization of defexpr when fast_only is true. + */ +void +InitVariable(Variable *var, Oid varid, bool fast_only) +{ + HeapTuple tup; + Form_pg_variable varform; + Datum defexpr_datum; + bool defexpr_isnull; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", varid); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + var->oid = varid; + var->create_lsn = varform->create_lsn; + var->name = pstrdup(NameStr(varform->varname)); + var->namespaceid = varform->varnamespace; + var->typid = varform->vartype; + var->typmod = varform->vartypmod; + var->owner = varform->varowner; + var->collation = varform->varcollation; + var->is_immutable = varform->varisimmutable; + var->is_not_null = varform->varisnotnull; + var->eoxaction = varform->vareoxaction; + + /* Get defexpr */ + defexpr_datum = SysCacheGetAttr(VARIABLEOID, + tup, + Anum_pg_variable_vardefexpr, + &defexpr_isnull); + + var->has_defexpr = !defexpr_isnull; + + /* + * Deserialize defexpr only when it is requested. We need to deserialize + * Node with default expression, only when we read from session variable, + * and this session variable has not assigned value, and this session + * variable has default expression. For other cases, we skip skip this + * operation. + */ + if (!fast_only && !defexpr_isnull) + var->defexpr = stringToNode(TextDatumGetCString(defexpr_datum)); + else + var->defexpr = NULL; + + ReleaseSysCache(tup); +} diff --git a/src/backend/commands/Makefile b/src/backend/commands/Makefile index 48f7348f91c..642454c745c 100644 --- a/src/backend/commands/Makefile +++ b/src/backend/commands/Makefile @@ -48,6 +48,7 @@ OBJS = \ proclang.o \ publicationcmds.o \ schemacmds.o \ + session_variable.o \ seclabel.o \ sequence.o \ statscmds.o \ diff --git a/src/backend/commands/alter.c b/src/backend/commands/alter.c index 55219bb0974..c39a2787588 100644 --- a/src/backend/commands/alter.c +++ b/src/backend/commands/alter.c @@ -40,6 +40,7 @@ #include "catalog/pg_ts_dict.h" #include "catalog/pg_ts_parser.h" #include "catalog/pg_ts_template.h" +#include "catalog/pg_variable.h" #include "commands/alter.h" #include "commands/collationcmds.h" #include "commands/conversioncmds.h" @@ -141,6 +142,10 @@ report_namespace_conflict(Oid classId, const char *name, Oid nspOid) Assert(OidIsValid(nspOid)); msgfmt = gettext_noop("text search configuration \"%s\" already exists in schema \"%s\""); break; + case VariableRelationId: + Assert(OidIsValid(nspOid)); + msgfmt = gettext_noop("session variable \"%s\" already exists in schema \"%s\""); + break; default: elog(ERROR, "unsupported object class %u", classId); break; @@ -393,6 +398,7 @@ ExecRenameStmt(RenameStmt *stmt) case OBJECT_TSTEMPLATE: case OBJECT_PUBLICATION: case OBJECT_SUBSCRIPTION: + case OBJECT_VARIABLE: { ObjectAddress address; Relation catalog; @@ -536,6 +542,7 @@ ExecAlterObjectSchemaStmt(AlterObjectSchemaStmt *stmt, case OBJECT_TSDICTIONARY: case OBJECT_TSPARSER: case OBJECT_TSTEMPLATE: + case OBJECT_VARIABLE: { Relation catalog; Relation relation; @@ -626,6 +633,7 @@ AlterObjectNamespace_oid(Oid classId, Oid objid, Oid nspOid, case OCLASS_TSDICT: case OCLASS_TSTEMPLATE: case OCLASS_TSCONFIG: + case OCLASS_VARIABLE: { Relation catalog; @@ -886,6 +894,7 @@ ExecAlterOwnerStmt(AlterOwnerStmt *stmt) case OBJECT_TABLESPACE: case OBJECT_TSDICTIONARY: case OBJECT_TSCONFIGURATION: + case OBJECT_VARIABLE: { Relation catalog; Relation relation; diff --git a/src/backend/commands/dropcmds.c b/src/backend/commands/dropcmds.c index 26157eb4e3f..b55b3b05286 100644 --- a/src/backend/commands/dropcmds.c +++ b/src/backend/commands/dropcmds.c @@ -480,6 +480,10 @@ does_not_exist_skipping(ObjectType objtype, Node *object) msg = gettext_noop("publication \"%s\" does not exist, skipping"); name = strVal(object); break; + case OBJECT_VARIABLE: + msg = gettext_noop("session variable \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + break; default: elog(ERROR, "unrecognized object type: %d", (int) objtype); break; diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c index 8d36b664880..875f19538ba 100644 --- a/src/backend/commands/event_trigger.c +++ b/src/backend/commands/event_trigger.c @@ -991,6 +991,7 @@ EventTriggerSupportsObjectType(ObjectType obtype) case OBJECT_TSTEMPLATE: case OBJECT_TYPE: case OBJECT_USER_MAPPING: + case OBJECT_VARIABLE: case OBJECT_VIEW: return true; @@ -1057,6 +1058,7 @@ EventTriggerSupportsObjectClass(ObjectClass objclass) case OCLASS_PUBLICATION_REL: case OCLASS_SUBSCRIPTION: case OCLASS_TRANSFORM: + case OCLASS_VARIABLE: return true; /* @@ -2049,6 +2051,8 @@ stringify_grant_objtype(ObjectType objtype) return "TABLESPACE"; case OBJECT_TYPE: return "TYPE"; + case OBJECT_VARIABLE: + return "VARIABLE"; /* these currently aren't used */ case OBJECT_ACCESS_METHOD: case OBJECT_AGGREGATE: @@ -2132,6 +2136,8 @@ stringify_adefprivs_objtype(ObjectType objtype) return "TABLESPACES"; case OBJECT_TYPE: return "TYPES"; + case OBJECT_VARIABLE: + return "VARIABLES"; /* these currently aren't used */ case OBJECT_ACCESS_METHOD: case OBJECT_AGGREGATE: diff --git a/src/backend/commands/seclabel.c b/src/backend/commands/seclabel.c index 7ae19b98bb9..9b113745356 100644 --- a/src/backend/commands/seclabel.c +++ b/src/backend/commands/seclabel.c @@ -92,6 +92,7 @@ SecLabelSupportsObjectType(ObjectType objtype) case OBJECT_TSPARSER: case OBJECT_TSTEMPLATE: case OBJECT_USER_MAPPING: + case OBJECT_VARIABLE: return false; /* diff --git a/src/backend/commands/session_variable.c b/src/backend/commands/session_variable.c new file mode 100644 index 00000000000..3eafc05f898 --- /dev/null +++ b/src/backend/commands/session_variable.c @@ -0,0 +1,242 @@ +/*------------------------------------------------------------------------- + * + * session_variable.c + * session variable creation/manipulation commands + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/backend/commands/sessionvariable.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "access/heapam.h" +#include "catalog/dependency.h" +#include "catalog/indexing.h" +#include "catalog/namespace.h" +#include "catalog/pg_variable.h" +#include "commands/session_variable.h" +#include "funcapi.h" +#include "miscadmin.h" +#include "utils/builtins.h" +#include "utils/lsyscache.h" +#include "utils/memutils.h" +#include "utils/syscache.h" + +/* + * The life cycle of temporary session variable can be + * limmited by using clause ON COMMIT DROP. + */ +typedef enum SVariableXActAction +{ + SVAR_ON_COMMIT_DROP, /* used for ON COMMIT DROP */ +} SVariableXActAction; + +typedef struct SVariableXActActionItem +{ + Oid varid; /* varid of session variable */ + + /* + * creating_subid is the ID of the creating subxact. If the action was + * unregistered during the current transaction, deleting_subid is the ID + * of the deleting subxact, otherwise InvalidSubTransactionId. + */ + SubTransactionId creating_subid; + SubTransactionId deleting_subid; +} SVariableXActActionItem; + +/* List holds fields of SVariableXActActionItem type */ +static List *xact_drop_actions = NIL; + +static void register_session_variable_xact_action(Oid varid, SVariableXActAction action); +static void unregister_session_variable_xact_action(Oid varid, SVariableXActAction action); + + +/* + * Do the necessary work to setup local memory management of a new + * variable. + * + * Caller should already have created the necessary entry in catalog + * and made them visible. + */ +void +SessionVariableCreatePostprocess(Oid varid, char eoxaction) +{ + /* + * For temporary variables, we need to create a new end of xact action to + * ensure deletion from catalog. + */ + if (eoxaction == VARIABLE_EOX_DROP) + { + Assert(isTempNamespace(get_session_variable_namespace(varid))); + + register_session_variable_xact_action(varid, SVAR_ON_COMMIT_DROP); + } +} + +/* + * Handle the local memory cleanup for a DROP VARIABLE command. + * + * Caller should take care of removing the pg_variable entry first. + */ +void +SessionVariableDropPostprocess(Oid varid) +{ + /* + * The entry was removed from catalog already, we must not do it + * again at end of xact time. + */ + unregister_session_variable_xact_action(varid, SVAR_ON_COMMIT_DROP); +} + +/* + * Registration of actions to be executed on session variables at transaction + * end time. We want to drop temporary session variables with clause ON COMMIT + * DROP, or we want to reset values of session variables with clause ON + * TRANSACTION END RESET or we want to clean (reset) local memory allocated by + * values of dropped session variables. + */ + +/* + * Register a session variable xact action. + */ +static void +register_session_variable_xact_action(Oid varid, + SVariableXActAction action) +{ + SVariableXActActionItem *xact_ai; + MemoryContext oldcxt; + + oldcxt = MemoryContextSwitchTo(CacheMemoryContext); + + xact_ai = (SVariableXActActionItem *) + palloc(sizeof(SVariableXActActionItem)); + + xact_ai->varid = varid; + + xact_ai->creating_subid = GetCurrentSubTransactionId(); + xact_ai->deleting_subid = InvalidSubTransactionId; + + Assert(action == SVAR_ON_COMMIT_DROP); + xact_drop_actions = lcons(xact_ai, xact_drop_actions); + + MemoryContextSwitchTo(oldcxt); +} + +/* + * Unregister an action on a given session variable from action list. In this + * moment, the action is just marked as deleted by setting deleting_subid. The + * calling even might be rollbacked, in which case we should not lose this + * action. + */ +static void +unregister_session_variable_xact_action(Oid varid, + SVariableXActAction action) +{ + ListCell *l; + + Assert(action == SVAR_ON_COMMIT_DROP); + + foreach(l, xact_drop_actions) + { + SVariableXActActionItem *xact_ai = + (SVariableXActActionItem *) lfirst(l); + + if (xact_ai->varid == varid) + xact_ai->deleting_subid = GetCurrentSubTransactionId(); + } +} + +/* + * Perform ON TRANSACTION END RESET or ON COMMIT DROP + * and COMMIT/ROLLBACK of transaction session variables. + */ +void +AtPreEOXact_SessionVariable_on_xact_actions(bool isCommit) +{ + ListCell *l; + + foreach(l, xact_drop_actions) + { + SVariableXActActionItem *xact_ai = + (SVariableXActActionItem *) lfirst(l); + + /* Iterate only over entries that are still pending */ + if (xact_ai->deleting_subid == InvalidSubTransactionId) + { + + /* + * ON COMMIT DROP is allowed only for temp session variables. So + * we should explicitly delete only when current transaction was + * committed. When it's rollback, then session variable is removed + * automatically. + */ + if (isCommit) + { + ObjectAddress object; + + object.classId = VariableRelationId; + object.objectId = xact_ai->varid; + object.objectSubId = 0; + + /* + * Since this is an automatic drop, rather than one directly + * initiated by the user, we pass the + * PERFORM_DELETION_INTERNAL flag. + */ + elog(DEBUG1, "session variable (oid:%u) will be deleted (forced by SVAR_ON_COMMIT_DROP action)", + xact_ai->varid); + + performDeletion(&object, DROP_CASCADE, + PERFORM_DELETION_INTERNAL | + PERFORM_DELETION_QUIETLY); + } + } + } + + /* + * Any drop action left is an entry that was unregistered and not + * rollbacked, so we can simply remove them. + */ + list_free_deep(xact_drop_actions); + xact_drop_actions = NIL; +} + +/* + * Post-subcommit or post-subabort cleanup of xact action list. + * + * During subabort, we can immediately remove entries created during this + * subtransaction. During subcommit, just transfer entries marked during + * this subtransaction as being the parent's responsibility. + */ +void +AtEOSubXact_SessionVariable_on_xact_actions(bool isCommit, SubTransactionId mySubid, + SubTransactionId parentSubid) +{ + ListCell *cur_item; + + foreach(cur_item, xact_drop_actions) + { + SVariableXActActionItem *xact_ai = + (SVariableXActActionItem *) lfirst(cur_item); + + if (!isCommit && xact_ai->creating_subid == mySubid) + { + /* cur_item must be removed */ + xact_drop_actions = foreach_delete_current(xact_drop_actions, cur_item); + pfree(xact_ai); + } + else + { + /* cur_item must be preserved */ + if (xact_ai->creating_subid == mySubid) + xact_ai->creating_subid = parentSubid; + if (xact_ai->deleting_subid == mySubid) + xact_ai->deleting_subid = isCommit ? parentSubid : InvalidSubTransactionId; + } + } +} diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 6007e10730a..4c484e2135f 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -47,6 +47,7 @@ #include "catalog/pg_tablespace.h" #include "catalog/pg_trigger.h" #include "catalog/pg_type.h" +#include "catalog/pg_variable.h" #include "catalog/storage.h" #include "catalog/storage_xlog.h" #include "catalog/toasting.h" @@ -6435,6 +6436,8 @@ ATTypedTableRecursion(List **wqueue, Relation rel, AlterTableCmd *cmd, * Eventually, we'd like to propagate the check or rewrite operation * into such tables, but for now, just error out if we find any. * + * Check if the type "typeOid" is used as type of some session variable too. + * * Caller should provide either the associated relation of a rowtype, * or a type name (not both) for use in the error message, if any. * @@ -6496,10 +6499,47 @@ find_composite_type_dependencies(Oid typeOid, Relation origRelation, continue; } + /* Don't allow change of type usedby session's variable */ + if (pg_depend->classid == VariableRelationId) + { + Oid varid = pg_depend->objid; + + if (origTypeName) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot alter type \"%s\" because session variable \"%s.%s\" uses it", + origTypeName, + get_namespace_name(get_session_variable_namespace(varid)), + get_session_variable_name(varid)))); + else if (origRelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot alter type \"%s\" because session variable \"%s.%s\" uses it", + RelationGetRelationName(origRelation), + get_namespace_name(get_session_variable_namespace(varid)), + get_session_variable_name(varid)))); + else if (origRelation->rd_rel->relkind == RELKIND_FOREIGN_TABLE) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot alter foreign table \"%s\" because session variable \"%s.%s\" uses it", + RelationGetRelationName(origRelation), + get_namespace_name(get_session_variable_namespace(varid)), + get_session_variable_name(varid)))); + else if (origRelation->rd_rel->relkind == RELKIND_RELATION || + origRelation->rd_rel->relkind == RELKIND_MATVIEW || + origRelation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot alter table \"%s\" because session variable \"%s.%s\" uses it", + RelationGetRelationName(origRelation), + get_namespace_name(get_session_variable_namespace(varid)), + get_session_variable_name(varid)))); + } + /* Else, ignore dependees that aren't user columns of relations */ /* (we assume system columns are never of interesting types) */ - if (pg_depend->classid != RelationRelationId || - pg_depend->objsubid <= 0) + else if (pg_depend->classid != RelationRelationId || + pg_depend->objsubid <= 0) continue; rel = relation_open(pg_depend->objid, AccessShareLock); @@ -12726,6 +12766,7 @@ ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel, case OCLASS_PUBLICATION_REL: case OCLASS_SUBSCRIPTION: case OCLASS_TRANSFORM: + case OCLASS_VARIABLE: /* * We don't expect any of these sorts of objects to depend on diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index deb101710e4..0fbe1d1e5ac 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -53,6 +53,7 @@ #include "catalog/namespace.h" #include "catalog/pg_am.h" #include "catalog/pg_trigger.h" +#include "catalog/pg_variable.h" #include "commands/defrem.h" #include "commands/trigger.h" #include "gramparse.h" @@ -294,8 +295,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); ConstraintsSetStmt CopyStmt CreateAsStmt CreateCastStmt CreateDomainStmt CreateExtensionStmt CreateGroupStmt CreateOpClassStmt CreateOpFamilyStmt AlterOpFamilyStmt CreatePLangStmt - CreateSchemaStmt CreateSeqStmt CreateStmt CreateStatsStmt CreateTableSpaceStmt - CreateFdwStmt CreateForeignServerStmt CreateForeignTableStmt + CreateSchemaStmt CreateSessionVarStmt CreateSeqStmt CreateStmt CreateStatsStmt + CreateTableSpaceStmt CreateFdwStmt CreateForeignServerStmt CreateForeignTableStmt CreateAssertionStmt CreateTransformStmt CreateTrigStmt CreateEventTrigStmt CreateUserStmt CreateUserMappingStmt CreateRoleStmt CreatePolicyStmt CreatedbStmt DeclareCursorStmt DefineStmt DeleteStmt DiscardStmt DoStmt @@ -475,6 +476,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); %type OptTemp %type OptNoLog %type OnCommitOption +%type OnEOXActionOption %type for_locking_strength %type for_locking_item @@ -644,6 +646,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); %type PartitionBoundSpec %type hash_partbound %type hash_partbound_elem +%type OptSessionVarDefExpr +%type OptNotNull OptImmutable /* @@ -754,8 +758,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); UESCAPE UNBOUNDED UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNLOGGED UNTIL UPDATE USER USING - VACUUM VALID VALIDATE VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING - VERBOSE VERSION_P VIEW VIEWS VOLATILE + VACUUM VALID VALIDATE VALIDATOR VALUE_P VALUES VARCHAR VARIABLE VARIABLES + VARIADIC VARYING VERBOSE VERSION_P VIEW VIEWS VOLATILE WHEN WHERE WHITESPACE_P WINDOW WITH WITHIN WITHOUT WORK WRAPPER WRITE @@ -1002,6 +1006,7 @@ stmt: | CreatePolicyStmt | CreatePLangStmt | CreateSchemaStmt + | CreateSessionVarStmt | CreateSeqStmt | CreateStmt | CreateSubscriptionStmt @@ -1546,6 +1551,7 @@ schema_stmt: | CreateTrigStmt | GrantStmt | ViewStmt + | CreateSessionVarStmt ; @@ -5010,6 +5016,69 @@ create_extension_opt_item: } ; +/***************************************************************************** + * + * QUERY : + * CREATE VARIABLE varname [AS] type + * + *****************************************************************************/ + +CreateSessionVarStmt: + CREATE OptTemp OptImmutable VARIABLE qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption + { + CreateSessionVarStmt *n = makeNode(CreateSessionVarStmt); + $5->relpersistence = $2; + n->is_immutable = $3; + n->variable = $5; + n->typeName = $7; + n->collClause = (CollateClause *) $8; + n->is_not_null = $9; + n->defexpr = $10; + n->eoxaction = $11; + n->if_not_exists = false; + $$ = (Node *) n; + } + | CREATE OptTemp OptImmutable VARIABLE IF_P NOT EXISTS qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption + { + CreateSessionVarStmt *n = makeNode(CreateSessionVarStmt); + $8->relpersistence = $2; + n->is_immutable = $3; + n->variable = $8; + n->typeName = $10; + n->collClause = (CollateClause *) $11; + n->is_not_null = $12; + n->defexpr = $13; + n->eoxaction = $14; + n->if_not_exists = true; + $$ = (Node *) n; + } + ; + +OptSessionVarDefExpr: DEFAULT b_expr { $$ = $2; } + | /* EMPTY */ { $$ = NULL; } + ; + +/* + * Temporary session variables can be dropped on successful + * transaction end like tables. RESET can only be forced on + * transaction end. Since the session variables are not + * transactional, we have to handle ROLLBACK too. + * The clause ON TRANSACTION END is clearer than some + * ON COMMIT ROLLBACK RESET clause. + */ +OnEOXActionOption: ON COMMIT DROP { $$ = VARIABLE_EOX_DROP; } + | ON TRANSACTION END_P RESET { $$ = VARIABLE_EOX_RESET; } + | /*EMPTY*/ { $$ = VARIABLE_EOX_NOOP; } + ; + +OptNotNull: NOT NULL_P { $$ = true; } + | /* EMPTY */ { $$ = false; } + ; + +OptImmutable: IMMUTABLE { $$ = true; } + | /* EMPTY */ { $$ = false; } + ; + /***************************************************************************** * * ALTER EXTENSION name UPDATE [ TO version ] @@ -6787,6 +6856,7 @@ object_type_any_name: | TEXT_P SEARCH DICTIONARY { $$ = OBJECT_TSDICTIONARY; } | TEXT_P SEARCH TEMPLATE { $$ = OBJECT_TSTEMPLATE; } | TEXT_P SEARCH CONFIGURATION { $$ = OBJECT_TSCONFIGURATION; } + | VARIABLE { $$ = OBJECT_VARIABLE; } ; /* @@ -7663,6 +7733,14 @@ privilege_target: n->objs = $2; $$ = n; } + | VARIABLE qualified_name_list + { + PrivTarget *n = (PrivTarget *) palloc(sizeof(PrivTarget)); + n->targtype = ACL_TARGET_OBJECT; + n->objtype = OBJECT_VARIABLE; + n->objs = $2; + $$ = n; + } | ALL TABLES IN_P SCHEMA name_list { PrivTarget *n = (PrivTarget *) palloc(sizeof(PrivTarget)); @@ -7708,6 +7786,14 @@ privilege_target: n->objs = $5; $$ = n; } + | ALL VARIABLES IN_P SCHEMA name_list + { + PrivTarget *n = (PrivTarget *) palloc(sizeof(PrivTarget)); + n->targtype = ACL_TARGET_ALL_IN_SCHEMA; + n->objtype = OBJECT_VARIABLE; + n->objs = $5; + $$ = n; + } ; @@ -7905,6 +7991,7 @@ defacl_privilege_target: | SEQUENCES { $$ = OBJECT_SEQUENCE; } | TYPES_P { $$ = OBJECT_TYPE; } | SCHEMAS { $$ = OBJECT_SCHEMA; } + | VARIABLES { $$ = OBJECT_VARIABLE; } ; @@ -9687,6 +9774,25 @@ RenameStmt: ALTER AGGREGATE aggregate_with_argtypes RENAME TO name n->missing_ok = false; $$ = (Node *) n; } + | ALTER VARIABLE any_name RENAME TO name + { + RenameStmt *n = makeNode(RenameStmt); + n->renameType = OBJECT_VARIABLE; + n->object = (Node *) $3; + n->newname = $6; + n->missing_ok = false; + $$ = (Node *)n; + } + | ALTER VARIABLE IF_P EXISTS any_name RENAME TO name + { + RenameStmt *n = makeNode(RenameStmt); + n->renameType = OBJECT_VARIABLE; + n->object = (Node *) $5; + n->newname = $8; + n->missing_ok = true; + $$ = (Node *)n; + } + ; opt_column: COLUMN @@ -10048,6 +10154,25 @@ AlterObjectSchemaStmt: n->missing_ok = false; $$ = (Node *) n; } + | ALTER VARIABLE any_name SET SCHEMA name + { + AlterObjectSchemaStmt *n = makeNode(AlterObjectSchemaStmt); + n->objectType = OBJECT_VARIABLE; + n->object = (Node *) $3; + n->newschema = $6; + n->missing_ok = false; + $$ = (Node *)n; + } + | ALTER VARIABLE IF_P EXISTS any_name SET SCHEMA name + { + AlterObjectSchemaStmt *n = makeNode(AlterObjectSchemaStmt); + n->objectType = OBJECT_VARIABLE; + n->object = (Node *) $5; + n->newschema = $8; + n->missing_ok = true; + $$ = (Node *)n; + } + ; /***************************************************************************** @@ -10327,6 +10452,14 @@ AlterOwnerStmt: ALTER AGGREGATE aggregate_with_argtypes OWNER TO RoleSpec n->newowner = $6; $$ = (Node *) n; } + | ALTER VARIABLE any_name OWNER TO RoleSpec + { + AlterOwnerStmt *n = makeNode(AlterOwnerStmt); + n->objectType = OBJECT_VARIABLE; + n->object = (Node *) $3; + n->newowner = $6; + $$ = (Node *)n; + } ; @@ -16941,6 +17074,8 @@ unreserved_keyword: | VALIDATE | VALIDATOR | VALUE_P + | VARIABLE + | VARIABLES | VARYING | VERSION_P | VIEW @@ -17552,6 +17687,8 @@ bare_label_keyword: | VALUE_P | VALUES | VARCHAR + | VARIABLE + | VARIABLES | VARIADIC | VERBOSE | VERSION_P diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c index 3ef9e8ee5e1..dbe630a51bc 100644 --- a/src/backend/parser/parse_agg.c +++ b/src/backend/parser/parse_agg.c @@ -471,6 +471,7 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr) break; case EXPR_KIND_COLUMN_DEFAULT: case EXPR_KIND_FUNCTION_DEFAULT: + case EXPR_KIND_VARIABLE_DEFAULT: if (isAgg) err = _("aggregate functions are not allowed in DEFAULT expressions"); @@ -915,6 +916,7 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc, break; case EXPR_KIND_COLUMN_DEFAULT: case EXPR_KIND_FUNCTION_DEFAULT: + case EXPR_KIND_VARIABLE_DEFAULT: err = _("window functions are not allowed in DEFAULT expressions"); break; case EXPR_KIND_INDEX_EXPRESSION: diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c index e5fc708c8a5..5b1fadf183e 100644 --- a/src/backend/parser/parse_expr.c +++ b/src/backend/parser/parse_expr.c @@ -16,6 +16,7 @@ #include "postgres.h" #include "catalog/pg_type.h" +#include "catalog/pg_variable.h" #include "commands/dbcommands.h" #include "miscadmin.h" #include "nodes/makefuncs.h" @@ -505,6 +506,8 @@ transformColumnRef(ParseState *pstate, ColumnRef *cref) case EXPR_KIND_COPY_WHERE: case EXPR_KIND_GENERATED_COLUMN: case EXPR_KIND_CYCLE_MARK: + case EXPR_KIND_VARIABLE_DEFAULT: + /* okay */ break; @@ -1726,6 +1729,7 @@ transformSubLink(ParseState *pstate, SubLink *sublink) break; case EXPR_KIND_COLUMN_DEFAULT: case EXPR_KIND_FUNCTION_DEFAULT: + case EXPR_KIND_VARIABLE_DEFAULT: err = _("cannot use subquery in DEFAULT expression"); break; case EXPR_KIND_INDEX_EXPRESSION: @@ -3066,6 +3070,7 @@ ParseExprKindName(ParseExprKind exprKind) return "CHECK"; case EXPR_KIND_COLUMN_DEFAULT: case EXPR_KIND_FUNCTION_DEFAULT: + case EXPR_KIND_VARIABLE_DEFAULT: return "DEFAULT"; case EXPR_KIND_INDEX_EXPRESSION: return "index expression"; diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c index 827989f3799..005bc0400f0 100644 --- a/src/backend/parser/parse_func.c +++ b/src/backend/parser/parse_func.c @@ -2621,6 +2621,7 @@ check_srf_call_placement(ParseState *pstate, Node *last_srf, int location) break; case EXPR_KIND_COLUMN_DEFAULT: case EXPR_KIND_FUNCTION_DEFAULT: + case EXPR_KIND_VARIABLE_DEFAULT: err = _("set-returning functions are not allowed in DEFAULT expressions"); break; case EXPR_KIND_INDEX_EXPRESSION: diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index 8140e79d8f1..339977a1427 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -107,6 +107,7 @@ typedef struct List *indexes; /* CREATE INDEX items */ List *triggers; /* CREATE TRIGGER items */ List *grants; /* GRANT items */ + List *variables; /* CREATE VARIABLE items */ } CreateSchemaStmtContext; @@ -3839,6 +3840,7 @@ transformCreateSchemaStmt(CreateSchemaStmt *stmt) cxt.indexes = NIL; cxt.triggers = NIL; cxt.grants = NIL; + cxt.variables = NIL; /* * Run through each schema element in the schema element list. Separate @@ -3907,6 +3909,15 @@ transformCreateSchemaStmt(CreateSchemaStmt *stmt) cxt.grants = lappend(cxt.grants, element); break; + case T_CreateSessionVarStmt: + { + CreateSessionVarStmt *elp = (CreateSessionVarStmt *) element; + + setSchemaName(cxt.schemaname, &elp->variable->schemaname); + cxt.variables = lappend(cxt.variables, element); + } + break; + default: elog(ERROR, "unrecognized node type: %d", (int) nodeTag(element)); @@ -3920,6 +3931,7 @@ transformCreateSchemaStmt(CreateSchemaStmt *stmt) result = list_concat(result, cxt.indexes); result = list_concat(result, cxt.triggers); result = list_concat(result, cxt.grants); + result = list_concat(result, cxt.variables); return result; } diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c index 247d0816ad8..d1a7d995e15 100644 --- a/src/backend/tcop/utility.c +++ b/src/backend/tcop/utility.c @@ -49,6 +49,7 @@ #include "commands/proclang.h" #include "commands/publicationcmds.h" #include "commands/schemacmds.h" +#include "commands/session_variable.h" #include "commands/seclabel.h" #include "commands/sequence.h" #include "commands/subscriptioncmds.h" @@ -189,6 +190,7 @@ ClassifyUtilityCommandAsReadOnly(Node *parsetree) case T_CreateRangeStmt: case T_CreateRoleStmt: case T_CreateSchemaStmt: + case T_CreateSessionVarStmt: case T_CreateSeqStmt: case T_CreateStatsStmt: case T_CreateStmt: @@ -1393,6 +1395,10 @@ ProcessUtilitySlow(ParseState *pstate, } break; + case T_CreateSessionVarStmt: + address = CreateVariable(pstate, (CreateSessionVarStmt *) parsetree); + break; + /* * ************* object creation / destruction ************** */ @@ -2332,6 +2338,9 @@ AlterObjectTypeCommandTag(ObjectType objtype) case OBJECT_STATISTIC_EXT: tag = CMDTAG_ALTER_STATISTICS; break; + case OBJECT_VARIABLE: + tag = CMDTAG_ALTER_VARIABLE; + break; default: tag = CMDTAG_UNKNOWN; break; @@ -2640,6 +2649,9 @@ CreateCommandTag(Node *parsetree) case OBJECT_STATISTIC_EXT: tag = CMDTAG_DROP_STATISTICS; break; + case OBJECT_VARIABLE: + tag = CMDTAG_DROP_VARIABLE; + break; default: tag = CMDTAG_UNKNOWN; } @@ -3216,6 +3228,10 @@ CreateCommandTag(Node *parsetree) } break; + case T_CreateSessionVarStmt: + tag = CMDTAG_CREATE_VARIABLE; + break; + default: elog(WARNING, "unrecognized node type: %d", (int) nodeTag(parsetree)); diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c index 4fac402e5b6..80a46b0925a 100644 --- a/src/backend/utils/adt/acl.c +++ b/src/backend/utils/adt/acl.c @@ -806,6 +806,10 @@ acldefault(ObjectType objtype, Oid ownerId) world_default = ACL_NO_RIGHTS; owner_default = ACL_ALL_RIGHTS_PARAMETER_ACL; break; + case OBJECT_VARIABLE: + world_default = ACL_NO_RIGHTS; + owner_default = ACL_ALL_RIGHTS_VARIABLE; + break; default: elog(ERROR, "unrecognized objtype: %d", (int) objtype); world_default = ACL_NO_RIGHTS; /* keep compiler quiet */ @@ -903,6 +907,9 @@ acldefault_sql(PG_FUNCTION_ARGS) case 'T': objtype = OBJECT_TYPE; break; + case 'V': + objtype = OBJECT_VARIABLE; + break; default: elog(ERROR, "unrecognized objtype abbreviation: %c", objtypec); } @@ -1605,7 +1612,6 @@ makeaclitem(PG_FUNCTION_ARGS) PG_RETURN_ACLITEM_P(result); } - /* * convert_any_priv_string: recognize privilege strings for has_foo_privilege * diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c index a16a63f4957..f4b1f57823e 100644 --- a/src/backend/utils/cache/lsyscache.c +++ b/src/backend/utils/cache/lsyscache.c @@ -36,6 +36,7 @@ #include "catalog/pg_subscription.h" #include "catalog/pg_transform.h" #include "catalog/pg_type.h" +#include "catalog/pg_variable.h" #include "miscadmin.h" #include "nodes/makefuncs.h" #include "utils/array.h" @@ -3679,3 +3680,115 @@ get_subscription_name(Oid subid, bool missing_ok) return subname; } + +/* ---------- PG_VARIABLE CACHE ---------- */ + +/* + * get_varname_varid + * Given name and namespace of variable, look up the OID. + */ +Oid +get_varname_varid(const char *varname, Oid varnamespace) +{ + return GetSysCacheOid2(VARIABLENAMENSP, Anum_pg_variable_oid, + PointerGetDatum(varname), + ObjectIdGetDatum(varnamespace)); +} + +/* + * get_session_variable_name + * Returns a palloc'd copy of the name of a given session variable. + */ +char * +get_session_variable_name(Oid varid) +{ + HeapTuple tup; + Form_pg_variable varform; + char *varname; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", varid); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + varname = pstrdup(NameStr(varform->varname)); + + ReleaseSysCache(tup); + + return varname; +} + +/* + * get_session_variable_namespace + * Returns the pg_namespace OID associated with a given session variable. + */ +Oid +get_session_variable_namespace(Oid varid) +{ + HeapTuple tup; + Form_pg_variable varform; + Oid varnamespace; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for variable %u", varid); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + varnamespace = varform->varnamespace; + + ReleaseSysCache(tup); + + return varnamespace; +} + +/* + * Returns the type, typmod and collid of the given session variable. + */ +Oid +get_session_variable_type(Oid varid) +{ + HeapTuple tup; + Form_pg_variable varform; + Oid vartype; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", varid); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + vartype = varform->vartype; + + ReleaseSysCache(tup); + + return vartype; +} + +/* + * Returns the type, typmod and collid of the given session variable. + */ +void +get_session_variable_type_typmod_collid(Oid varid, Oid *typid, int32 *typmod, + Oid *collid) +{ + HeapTuple tup; + Form_pg_variable varform; + + tup = SearchSysCache1(VARIABLEOID, ObjectIdGetDatum(varid)); + + if (!HeapTupleIsValid(tup)) + elog(ERROR, "cache lookup failed for session variable %u", varid); + + varform = (Form_pg_variable) GETSTRUCT(tup); + + *typid = varform->vartype; + *typmod = varform->vartypmod; + *collid = varform->varcollation; + + ReleaseSysCache(tup); +} diff --git a/src/backend/utils/cache/syscache.c b/src/backend/utils/cache/syscache.c index eec644ec848..b6d756a056d 100644 --- a/src/backend/utils/cache/syscache.c +++ b/src/backend/utils/cache/syscache.c @@ -75,6 +75,7 @@ #include "catalog/pg_ts_template.h" #include "catalog/pg_type.h" #include "catalog/pg_user_mapping.h" +#include "catalog/pg_variable.h" #include "lib/qunique.h" #include "utils/catcache.h" #include "utils/rel.h" @@ -1037,6 +1038,28 @@ static const struct cachedesc cacheinfo[] = { 0 }, 2 + }, + {VariableRelationId, /* VARIABLENAMENSP */ + VariableNameNspIndexId, + 2, + { + Anum_pg_variable_varname, + Anum_pg_variable_varnamespace, + 0, + 0 + }, + 8 + }, + {VariableRelationId, /* VARIABLEOID */ + VariableObjectIndexId, + 1, + { + Anum_pg_variable_oid, + 0, + 0, + 0 + }, + 8 } }; diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c index a9dd068095b..af74fe345ed 100644 --- a/src/backend/utils/fmgr/fmgr.c +++ b/src/backend/utils/fmgr/fmgr.c @@ -1896,9 +1896,9 @@ get_call_expr_arg_stable(Node *expr, int argnum) arg = (Node *) list_nth(args, argnum); /* - * Either a true Const or an external Param will have a value that doesn't - * change during the execution of the query. In future we might want to - * consider other cases too, e.g. now(). + * Either a true Const or an external Param or variable will have a value + * that doesn't change during the execution of the query. In future we + * might want to consider other cases too, e.g. now(). */ if (IsA(arg, Const)) return true; diff --git a/src/include/catalog/dependency.h b/src/include/catalog/dependency.h index 98a1a842890..84a851bfa6d 100644 --- a/src/include/catalog/dependency.h +++ b/src/include/catalog/dependency.h @@ -127,10 +127,11 @@ typedef enum ObjectClass OCLASS_PUBLICATION_NAMESPACE, /* pg_publication_namespace */ OCLASS_PUBLICATION_REL, /* pg_publication_rel */ OCLASS_SUBSCRIPTION, /* pg_subscription */ - OCLASS_TRANSFORM /* pg_transform */ + OCLASS_TRANSFORM, /* pg_transform */ + OCLASS_VARIABLE /* pg_variable */ } ObjectClass; -#define LAST_OCLASS OCLASS_TRANSFORM +#define LAST_OCLASS OCLASS_VARIABLE /* flag bits for performDeletion/performMultipleDeletions: */ #define PERFORM_DELETION_INTERNAL 0x0001 /* internal action */ diff --git a/src/include/catalog/meson.build b/src/include/catalog/meson.build index 45ffa99692e..d041d728fb9 100644 --- a/src/include/catalog/meson.build +++ b/src/include/catalog/meson.build @@ -63,6 +63,7 @@ catalog_headers = [ 'pg_publication_rel.h', 'pg_subscription.h', 'pg_subscription_rel.h', + 'pg_variable.h', ] bki_data = [ diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h index 2a2a2e6489e..e6873d369af 100644 --- a/src/include/catalog/namespace.h +++ b/src/include/catalog/namespace.h @@ -96,6 +96,8 @@ extern Oid TypenameGetTypid(const char *typname); extern Oid TypenameGetTypidExtended(const char *typname, bool temp_ok); extern bool TypeIsVisible(Oid typid); +extern bool VariableIsVisible(Oid varid); + extern FuncCandidateList FuncnameGetCandidates(List *names, int nargs, List *argnames, bool expand_variadic, @@ -164,6 +166,11 @@ extern void SetTempNamespaceState(Oid tempNamespaceId, Oid tempToastNamespaceId); extern void ResetTempTableNamespace(void); +extern List *NamesFromList(List *names); +extern Oid LookupVariable(const char *nspname, const char *varname, bool rowtype_only, + bool missing_ok); +extern Oid IdentifyVariable(List *names, char **attrname, bool *not_unique); + extern OverrideSearchPath *GetOverrideSearchPath(MemoryContext context); extern OverrideSearchPath *CopyOverrideSearchPath(OverrideSearchPath *path); extern bool OverrideSearchPathMatchesCurrent(OverrideSearchPath *path); diff --git a/src/include/catalog/pg_default_acl.h b/src/include/catalog/pg_default_acl.h index 2a791556362..672c5715620 100644 --- a/src/include/catalog/pg_default_acl.h +++ b/src/include/catalog/pg_default_acl.h @@ -66,6 +66,7 @@ DECLARE_UNIQUE_INDEX_PKEY(pg_default_acl_oid_index, 828, DefaultAclOidIndexId, o #define DEFACLOBJ_FUNCTION 'f' /* function */ #define DEFACLOBJ_TYPE 'T' /* type */ #define DEFACLOBJ_NAMESPACE 'n' /* namespace */ +#define DEFACLOBJ_VARIABLE 'V' /* variable */ #endif /* EXPOSE_TO_CLIENT_CODE */ diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 20f5aa56eab..3bbae2fae46 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -6282,6 +6282,9 @@ proname => 'pg_collation_is_visible', procost => '10', provolatile => 's', prorettype => 'bool', proargtypes => 'oid', prosrc => 'pg_collation_is_visible' }, +{ oid => '9221', descr => 'is session variable visible in search path?', + proname => 'pg_variable_is_visible', procost => '10', provolatile => 's', + prorettype => 'bool', proargtypes => 'oid', prosrc => 'pg_variable_is_visible' }, { oid => '2854', descr => 'get OID of current session\'s temp schema, if any', proname => 'pg_my_temp_schema', provolatile => 's', proparallel => 'r', diff --git a/src/include/catalog/pg_variable.h b/src/include/catalog/pg_variable.h new file mode 100644 index 00000000000..cde36b0ceab --- /dev/null +++ b/src/include/catalog/pg_variable.h @@ -0,0 +1,120 @@ +/*------------------------------------------------------------------------- + * + * pg_variable.h + * definition of session variables system catalog (pg_variables) + * + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/catalog/pg_variable.h + * + * NOTES + * The Catalog.pm module reads this file and derives schema + * information. + * + *------------------------------------------------------------------------- + */ +#ifndef PG_VARIABLE_H +#define PG_VARIABLE_H + +#include "catalog/genbki.h" +#include "catalog/objectaddress.h" +#include "catalog/pg_variable_d.h" +#include "utils/acl.h" + +/* ---------------- + * pg_variable definition. cpp turns this into + * typedef struct FormData_pg_variable + * ---------------- + */ +CATALOG(pg_variable,9222,VariableRelationId) +{ + Oid oid; /* oid */ + + /* OID of entry in pg_type for variable's type */ + Oid vartype BKI_LOOKUP(pg_type); + + /* Used for identity check [oid, create_lsn] */ + XLogRecPtr create_lsn; + + /* variable name */ + NameData varname; + + /* OID of namespace containing variable class */ + Oid varnamespace BKI_LOOKUP(pg_namespace); + + /* typmode for variable's type */ + int32 vartypmod; + + /* variable owner */ + Oid varowner BKI_LOOKUP(pg_authid); + + /* variable collation */ + Oid varcollation BKI_LOOKUP_OPT(pg_collation); + + /* Don't allow NULL */ + bool varisnotnull; + + /* Don't allow changes */ + bool varisimmutable; + + /* action on transaction end */ + char vareoxaction; + +#ifdef CATALOG_VARLEN /* variable-length fields start here */ + + /* list of expression trees for variable default (NULL if none) */ + pg_node_tree vardefexpr BKI_DEFAULT(_null_); + + /* access permissions */ + aclitem varacl[1] BKI_DEFAULT(_null_); + +#endif +} FormData_pg_variable; + +typedef enum VariableEOXAction +{ + VARIABLE_EOX_NOOP = 'n', /* NOOP */ + VARIABLE_EOX_DROP = 'd', /* ON COMMIT DROP */ + VARIABLE_EOX_RESET = 'r', /* ON TRANSACTION END RESET */ +} VariableEOXAction; + +/* ---------------- + * Form_pg_variable corresponds to a pointer to a tuple with + * the format of pg_variable relation. + * ---------------- + */ +typedef FormData_pg_variable *Form_pg_variable; + +DECLARE_TOAST(pg_variable, 9223, 9224); + +DECLARE_UNIQUE_INDEX_PKEY(pg_variable_oid_index, 9225, VariableOidIndexId, on pg_variable using btree(oid oid_ops)); +#define VariableObjectIndexId 9225 + +DECLARE_UNIQUE_INDEX(pg_variable_varname_nsp_index, 9226, VariableNameNspIndexId, on pg_variable using btree(varname name_ops, varnamespace oid_ops)); +#define VariableNameNspIndexId 9226 + +typedef struct Variable +{ + Oid oid; + Oid typid; + XLogRecPtr create_lsn; + char *name; + Oid namespaceid; + int32 typmod; + Oid owner; + Oid collation; + bool is_not_null; + bool is_immutable; + VariableEOXAction eoxaction; + bool has_defexpr; + Node *defexpr; +} Variable; + +extern ObjectAddress CreateVariable(ParseState *pstate, + CreateSessionVarStmt *stmt); +extern void DropVariable(Oid varid); +extern void InitVariable(Variable *var, Oid varid, bool fast_only); + +#endif /* PG_VARIABLE_H */ diff --git a/src/include/commands/session_variable.h b/src/include/commands/session_variable.h new file mode 100644 index 00000000000..51934e8d1a8 --- /dev/null +++ b/src/include/commands/session_variable.h @@ -0,0 +1,41 @@ +/*------------------------------------------------------------------------- + * + * sessionvariable.h + * prototypes for sessionvariable.c. + * + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/commands/session_variable.h + * + *------------------------------------------------------------------------- + */ + +#ifndef SESSIONVARIABLE_H +#define SESSIONVARIABLE_H + +#include "catalog/objectaddress.h" +#include "catalog/pg_variable.h" +#include "nodes/params.h" +#include "nodes/parsenodes.h" +#include "nodes/plannodes.h" +#include "tcop/cmdtag.h" +#include "utils/queryenvironment.h" + +extern void ResetSessionVariables(void); +extern void SessionVariableCreatePostprocess(Oid varid, char eoxaction); +extern void SessionVariableDropPostprocess(Oid varid); + +extern Datum CopySessionVariable(Oid varid, bool *isNull, Oid *typid); +extern Datum CopySessionVariableWithTypeCheck(Oid varid, bool *isNull, Oid expected_typid); +extern Datum GetSessionVariableWithTypeCheck(Oid varid, bool *isNull, Oid expected_typid); + +extern void SetSessionVariable(Oid varid, Datum value, bool isNull, Oid typid); +extern void SetSessionVariableWithSecurityCheck(Oid varid, Datum value, bool isNull, Oid typid); + +extern void AtPreEOXact_SessionVariable_on_xact_actions(bool isCommit); +extern void AtEOSubXact_SessionVariable_on_xact_actions(bool isCommit, SubTransactionId mySubid, + SubTransactionId parentSubid); + +#endif diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index 7caff62af7f..e85878e13ec 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1909,6 +1909,7 @@ typedef enum ObjectType OBJECT_TSTEMPLATE, OBJECT_TYPE, OBJECT_USER_MAPPING, + OBJECT_VARIABLE, OBJECT_VIEW } ObjectType; @@ -3036,6 +3037,25 @@ typedef struct AlterStatsStmt bool missing_ok; /* skip error if statistics object is missing */ } AlterStatsStmt; + +/* ---------------------- + * {Create|Alter} VARIABLE Statement + * ---------------------- + */ +typedef struct CreateSessionVarStmt +{ + NodeTag type; + RangeVar *variable; /* the variable to create */ + TypeName *typeName; /* the type of variable */ + CollateClause *collClause; + Node *defexpr; /* default expression */ + char eoxaction; /* on commit action */ + bool if_not_exists; /* do nothing if it already exists */ + bool is_not_null; /* Disallow nulls */ + bool is_immutable; /* Don't allow changes */ +} CreateSessionVarStmt; + + /* ---------------------- * Create Function Statement * ---------------------- diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h index 957ee18d849..0eb85fabc0d 100644 --- a/src/include/parser/kwlist.h +++ b/src/include/parser/kwlist.h @@ -454,6 +454,8 @@ PG_KEYWORD("validator", VALIDATOR, UNRESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("value", VALUE_P, UNRESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("values", VALUES, COL_NAME_KEYWORD, BARE_LABEL) PG_KEYWORD("varchar", VARCHAR, COL_NAME_KEYWORD, BARE_LABEL) +PG_KEYWORD("variable", VARIABLE, UNRESERVED_KEYWORD, BARE_LABEL) +PG_KEYWORD("variables", VARIABLES, UNRESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("variadic", VARIADIC, RESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("varying", VARYING, UNRESERVED_KEYWORD, AS_LABEL) PG_KEYWORD("verbose", VERBOSE, TYPE_FUNC_NAME_KEYWORD, BARE_LABEL) diff --git a/src/include/parser/parse_node.h b/src/include/parser/parse_node.h index 962ebf65de1..4d65a9e9e8e 100644 --- a/src/include/parser/parse_node.h +++ b/src/include/parser/parse_node.h @@ -81,6 +81,7 @@ typedef enum ParseExprKind EXPR_KIND_COPY_WHERE, /* WHERE condition in COPY FROM */ EXPR_KIND_GENERATED_COLUMN, /* generation expression for a column */ EXPR_KIND_CYCLE_MARK, /* cycle mark value */ + EXPR_KIND_VARIABLE_DEFAULT /* default value for session variable */ } ParseExprKind; diff --git a/src/include/tcop/cmdtaglist.h b/src/include/tcop/cmdtaglist.h index 9e94f44c5f4..6c1be5e9d4b 100644 --- a/src/include/tcop/cmdtaglist.h +++ b/src/include/tcop/cmdtaglist.h @@ -68,6 +68,7 @@ PG_CMDTAG(CMDTAG_ALTER_TRANSFORM, "ALTER TRANSFORM", true, false, false) PG_CMDTAG(CMDTAG_ALTER_TRIGGER, "ALTER TRIGGER", true, false, false) PG_CMDTAG(CMDTAG_ALTER_TYPE, "ALTER TYPE", true, true, false) PG_CMDTAG(CMDTAG_ALTER_USER_MAPPING, "ALTER USER MAPPING", true, false, false) +PG_CMDTAG(CMDTAG_ALTER_VARIABLE, "ALTER VARIABLE", true, false, false) PG_CMDTAG(CMDTAG_ALTER_VIEW, "ALTER VIEW", true, false, false) PG_CMDTAG(CMDTAG_ANALYZE, "ANALYZE", false, false, false) PG_CMDTAG(CMDTAG_BEGIN, "BEGIN", false, false, false) @@ -123,6 +124,7 @@ PG_CMDTAG(CMDTAG_CREATE_TRANSFORM, "CREATE TRANSFORM", true, false, false) PG_CMDTAG(CMDTAG_CREATE_TRIGGER, "CREATE TRIGGER", true, false, false) PG_CMDTAG(CMDTAG_CREATE_TYPE, "CREATE TYPE", true, false, false) PG_CMDTAG(CMDTAG_CREATE_USER_MAPPING, "CREATE USER MAPPING", true, false, false) +PG_CMDTAG(CMDTAG_CREATE_VARIABLE, "CREATE VARIABLE", true, false, false) PG_CMDTAG(CMDTAG_CREATE_VIEW, "CREATE VIEW", true, false, false) PG_CMDTAG(CMDTAG_DEALLOCATE, "DEALLOCATE", false, false, false) PG_CMDTAG(CMDTAG_DEALLOCATE_ALL, "DEALLOCATE ALL", false, false, false) @@ -175,6 +177,7 @@ PG_CMDTAG(CMDTAG_DROP_TRANSFORM, "DROP TRANSFORM", true, false, false) PG_CMDTAG(CMDTAG_DROP_TRIGGER, "DROP TRIGGER", true, false, false) PG_CMDTAG(CMDTAG_DROP_TYPE, "DROP TYPE", true, false, false) PG_CMDTAG(CMDTAG_DROP_USER_MAPPING, "DROP USER MAPPING", true, false, false) +PG_CMDTAG(CMDTAG_DROP_VARIABLE, "DROP VARIABLE", true, false, false) PG_CMDTAG(CMDTAG_DROP_VIEW, "DROP VIEW", true, false, false) PG_CMDTAG(CMDTAG_EXECUTE, "EXECUTE", false, false, false) PG_CMDTAG(CMDTAG_EXPLAIN, "EXPLAIN", false, false, false) diff --git a/src/include/utils/acl.h b/src/include/utils/acl.h index 9a4df3a5dac..8070eb14528 100644 --- a/src/include/utils/acl.h +++ b/src/include/utils/acl.h @@ -168,6 +168,7 @@ typedef struct ArrayType Acl; #define ACL_ALL_RIGHTS_SCHEMA (ACL_USAGE|ACL_CREATE) #define ACL_ALL_RIGHTS_TABLESPACE (ACL_CREATE) #define ACL_ALL_RIGHTS_TYPE (ACL_USAGE) +#define ACL_ALL_RIGHTS_VARIABLE (ACL_SELECT|ACL_UPDATE) /* operation codes for pg_*_aclmask */ typedef enum @@ -267,7 +268,8 @@ extern AclMode pg_foreign_server_aclmask(Oid srv_oid, Oid roleid, AclMode mask, AclMaskHow how); extern AclMode pg_type_aclmask(Oid type_oid, Oid roleid, AclMode mask, AclMaskHow how); - +extern AclMode pg_variable_aclmask(Oid var_oid, Oid roleid, + AclMode mask, AclMaskHow how); extern AclResult pg_attribute_aclcheck(Oid table_oid, AttrNumber attnum, Oid roleid, AclMode mode); extern AclResult pg_attribute_aclcheck_ext(Oid table_oid, AttrNumber attnum, @@ -292,6 +294,7 @@ extern AclResult pg_tablespace_aclcheck(Oid spc_oid, Oid roleid, AclMode mode); extern AclResult pg_foreign_data_wrapper_aclcheck(Oid fdw_oid, Oid roleid, AclMode mode); extern AclResult pg_foreign_server_aclcheck(Oid srv_oid, Oid roleid, AclMode mode); extern AclResult pg_type_aclcheck(Oid type_oid, Oid roleid, AclMode mode); +extern AclResult pg_variable_aclcheck(Oid var_oid, Oid roleid, AclMode mode); extern void aclcheck_error(AclResult aclerr, ObjectType objtype, const char *objectname); @@ -328,6 +331,7 @@ extern bool pg_extension_ownercheck(Oid ext_oid, Oid roleid); extern bool pg_publication_ownercheck(Oid pub_oid, Oid roleid); extern bool pg_subscription_ownercheck(Oid sub_oid, Oid roleid); extern bool pg_statistics_object_ownercheck(Oid stat_oid, Oid roleid); +extern bool pg_variable_ownercheck(Oid stat_oid, Oid roleid); extern bool has_createrole_privilege(Oid roleid); extern bool has_bypassrls_privilege(Oid roleid); diff --git a/src/include/utils/lsyscache.h b/src/include/utils/lsyscache.h index 50f02883052..10d97ffbf34 100644 --- a/src/include/utils/lsyscache.h +++ b/src/include/utils/lsyscache.h @@ -132,6 +132,7 @@ extern char get_func_prokind(Oid funcid); extern bool get_func_leakproof(Oid funcid); extern RegProcedure get_func_support(Oid funcid); extern Oid get_relname_relid(const char *relname, Oid relnamespace); +extern Oid get_varname_varid(const char *varname, Oid varnamespace); extern char *get_rel_name(Oid relid); extern Oid get_rel_namespace(Oid relid); extern Oid get_rel_type_id(Oid relid); @@ -203,6 +204,14 @@ extern char *get_publication_name(Oid pubid, bool missing_ok); extern Oid get_subscription_oid(const char *subname, bool missing_ok); extern char *get_subscription_name(Oid subid, bool missing_ok); +extern char *get_session_variable_name(Oid varid); +extern Oid get_session_variable_namespace(Oid varid); +extern Oid get_session_variable_type(Oid varid); +extern void get_session_variable_type_typmod_collid(Oid varid, + Oid *typid, + int32 *typmod, + Oid *collid); + #define type_is_array(typid) (get_element_type(typid) != InvalidOid) /* type_is_array_domain accepts both plain arrays and domains over arrays */ #define type_is_array_domain(typid) (get_base_element_type(typid) != InvalidOid) diff --git a/src/include/utils/syscache.h b/src/include/utils/syscache.h index 4463ea66bea..3d18dc88ac4 100644 --- a/src/include/utils/syscache.h +++ b/src/include/utils/syscache.h @@ -113,9 +113,11 @@ enum SysCacheIdentifier TYPENAMENSP, TYPEOID, USERMAPPINGOID, - USERMAPPINGUSERSERVER + USERMAPPINGUSERSERVER, + VARIABLENAMENSP, + VARIABLEOID -#define SysCacheSize (USERMAPPINGUSERSERVER + 1) +#define SysCacheSize (VARIABLEOID + 1) }; extern void InitCatalogCache(void); diff --git a/src/test/regress/expected/oidjoins.out b/src/test/regress/expected/oidjoins.out index 215eb899be3..d9953321402 100644 --- a/src/test/regress/expected/oidjoins.out +++ b/src/test/regress/expected/oidjoins.out @@ -266,3 +266,7 @@ NOTICE: checking pg_subscription {subdbid} => pg_database {oid} NOTICE: checking pg_subscription {subowner} => pg_authid {oid} NOTICE: checking pg_subscription_rel {srsubid} => pg_subscription {oid} NOTICE: checking pg_subscription_rel {srrelid} => pg_class {oid} +NOTICE: checking pg_variable {vartype} => pg_type {oid} +NOTICE: checking pg_variable {varnamespace} => pg_namespace {oid} +NOTICE: checking pg_variable {varowner} => pg_authid {oid} +NOTICE: checking pg_variable {varcollation} => pg_collation {oid} diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index 9683b0a88e5..6778bbb80d1 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -500,6 +500,7 @@ CreateRoleStmt CreateSchemaStmt CreateSchemaStmtContext CreateSeqStmt +CreateSessionVarStmt CreateStatsStmt CreateStmt CreateStmtContext @@ -883,6 +884,7 @@ Form_pg_ts_parser Form_pg_ts_template Form_pg_type Form_pg_user_mapping +FormData_pg_variable FormatNode FreeBlockNumberArray FreeListData @@ -2636,6 +2638,8 @@ SupportRequestRows SupportRequestSelectivity SupportRequestSimplify SupportRequestWFuncMonotonic +SVariableXActAction +SVariableXActActionItem Syn SyncOps SyncRepConfigData -- 2.38.1