/*------------------------------------------------------------------------- * * lsyscache.c-- * Routines to access information within system caches * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * /usr/local/devel/pglite/cvs/src/backend/utils/cache/lsyscache.c,v 1.8 1995/03/03 07:36:01 andrew Exp * * NOTES * Eventually, the index information should go through here, too. * * Most of these routines call SearchSysCacheStruct() and thus simply * (1) allocate some space for the return struct and (2) call it. * *------------------------------------------------------------------------- */ #include #include "postgres.h" #include "nodes/pg_list.h" #include "utils/syscache.h" #include "utils/lsyscache.h" #include "access/tupmacs.h" #include "utils/rel.h" #include "utils/palloc.h" #include "utils/elog.h" #include "access/attnum.h" #include "catalog/pg_amop.h" #include "catalog/pg_type.h" /* ---------- AMOP CACHES ---------- */ /* * op_class - * * Return t iff operator 'opno' is in operator class 'opclass'. * */ bool op_class(Oid opno, int32 opclass) { FormData_pg_amop amoptup; if (SearchSysCacheStruct(AMOPOPID, (char *) &amoptup, (char *) ObjectIdGetDatum(opclass), (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL)) return(true); else return(false); } /* ---------- ATTRIBUTE CACHES ---------- */ /* * get_attname - * * Given the relation id and the attribute number, * return the "attname" field from the attribute relation. * */ Name get_attname(Oid relid, AttrNumber attnum) { FormData_pg_attribute att_tup; Name retval = (Name)NULL; if (SearchSysCacheStruct(ATTNUM, (char *) &att_tup, (char *) ObjectIdGetDatum(relid), (char *) UInt16GetDatum(attnum), (char *) NULL, (char *) NULL)) { retval = (Name)palloc(sizeof(att_tup.attname)); memmove(retval, &(att_tup.attname), sizeof(att_tup.attname)); return(retval); } else return((Name)NULL); } /* * get_attnum - * * Given the relation id and the attribute name, * return the "attnum" field from the attribute relation. * */ AttrNumber get_attnum(Oid relid, Name attname) { FormData_pg_attribute att_tup; if (SearchSysCacheStruct(ATTNAME, (char *) &att_tup, (char *) ObjectIdGetDatum(relid), (char *) attname, (char *) NULL, (char *) NULL)) return(att_tup.attnum); else return(InvalidAttrNumber); } /* * get_atttype - * * Given the relation OID and the attribute number with the relation, * return the attribute type OID. * */ Oid get_atttype(Oid relid, AttrNumber attnum) { AttributeTupleForm att_tup = (AttributeTupleForm)palloc(sizeof(*att_tup)); if (SearchSysCacheStruct(ATTNUM, (char *) att_tup, (char *) ObjectIdGetDatum(relid), (char *) UInt16GetDatum(attnum), (char *) NULL, (char *) NULL)) return(att_tup->atttypid); else return((Oid)NULL); } /* This routine uses the attname instead of the attnum because it * replaces the routine find_atttype, which is called sometimes when * only the attname, not the attno, is available. */ bool get_attisset(Oid relid, Name attname) { HeapTuple htup; AttrNumber attno; AttributeTupleForm att_tup; attno = get_attnum(relid, attname); htup = SearchSysCacheTuple(ATTNAME, (char *) ObjectIdGetDatum(relid), (char *) attname, (char *) NULL, (char *) NULL); if (!HeapTupleIsValid(htup)) elog(WARN, "get_attisset: no attribute %.16s in relation %d", attname->data, relid); if (heap_attisnull(htup, attno)) return(false); else { att_tup = (AttributeTupleForm)GETSTRUCT(htup); return(att_tup->attisset); } } /* ---------- INDEX CACHE ---------- */ /* watch this space... */ /* ---------- OPERATOR CACHE ---------- */ /* * get_opcode - * * Returns the regproc id of the routine used to implement an * operator given the operator uid. * */ RegProcedure get_opcode(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return(optup.oprcode); else return((RegProcedure)NULL); } /* * get_opname - * returns the name of the operator with the given opno * * Note: return the struct so that it gets copied. */ NameData get_opname(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return (optup.oprname); else elog(WARN, "can't look up operator %d\n", opno); } /* * op_mergesortable - * * Returns the left and right sort operators and types corresponding to a * mergesortable operator, or nil if the operator is not mergesortable. * */ bool op_mergesortable(Oid opno, Oid ltype, Oid rtype, Oid *leftOp, Oid *rightOp) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL) && optup.oprlsortop && optup.oprrsortop && optup.oprleft == ltype && optup.oprright == rtype) { *leftOp = ObjectIdGetDatum(optup.oprlsortop); *rightOp = ObjectIdGetDatum(optup.oprrsortop); return TRUE; } else { return FALSE; } } /* * op_hashjoinable-- * * Returns the hash operator corresponding to a hashjoinable operator, * or nil if the operator is not hashjoinable. * */ Oid op_hashjoinable(Oid opno, Oid ltype, Oid rtype) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL) && optup.oprcanhash && optup.oprleft == ltype && optup.oprright == rtype) return(opno); else return(InvalidOid); } /* * get_commutator - * * Returns the corresponding commutator of an operator. * */ Oid get_commutator(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return(optup.oprcom); else return((Oid)NULL); } HeapTuple get_operator_tuple(Oid opno) { HeapTuple optup; if ((optup = SearchSysCacheTuple(OPROID, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL))) return(optup); else return((HeapTuple)NULL); } /* * get_negator - * * Returns the corresponding negator of an operator. * */ Oid get_negator(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return(optup.oprnegate); else return((Oid)NULL); } /* * get_oprrest - * * Returns procedure id for computing selectivity of an operator. * */ RegProcedure get_oprrest(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return(optup.oprrest ); else return((RegProcedure) NULL); } /* * get_oprjoin - * * Returns procedure id for computing selectivity of a join. * */ RegProcedure get_oprjoin(Oid opno) { FormData_pg_operator optup; if (SearchSysCacheStruct(OPROID, (char *) &optup, (char *) ObjectIdGetDatum(opno), (char *) NULL, (char *) NULL, (char *) NULL)) return(optup.oprjoin); else return((RegProcedure)NULL); } /* ---------- RELATION CACHE ---------- */ /* * get_relnatts - * * Returns the number of attributes for a given relation. * */ int get_relnatts(Oid relid) { FormData_pg_class reltup; if (SearchSysCacheStruct(RELOID, (char *) &reltup, (char *) ObjectIdGetDatum(relid), (char *) NULL, (char *) NULL, (char *) NULL)) return(reltup.relnatts); else return(InvalidAttrNumber); } /* * get_rel_name - * * Returns the name of a given relation. * */ Name get_rel_name(Oid relid) { FormData_pg_class reltup; Name retval = (Name)NULL; if ((SearchSysCacheStruct(RELOID, (char *) &reltup, (char *) ObjectIdGetDatum(relid), (char *) NULL, (char *) NULL, (char *) NULL))) { retval = (Name)palloc(sizeof(reltup.relname)); memmove(retval, &(reltup.relname), sizeof(reltup.relname)); return (retval); } else return((Name)NULL); } /* ---------- TYPE CACHE ---------- */ /* * get_typlen - * * Given the type OID, return the length of the type. * */ int16 get_typlen(Oid typid) { TypeTupleFormData typtup; if (SearchSysCacheStruct(TYPOID, (char *) &typtup, (char *) ObjectIdGetDatum(typid), (char *) NULL, (char *) NULL, (char *) NULL)) return(typtup.typlen); else return((int16)NULL); } /* * get_typbyval - * * Given the type OID, determine whether the type is returned by value or * not. Returns 1 if by value, 0 if by reference. * */ bool get_typbyval(Oid typid) { TypeTupleFormData typtup; if (SearchSysCacheStruct(TYPOID, (char *) &typtup, (char *) ObjectIdGetDatum(typid), (char *) NULL, (char *) NULL, (char *) NULL)) return((bool)typtup.typbyval); else return(false); } /* * get_typbyval - * * Given the type OID, determine whether the type is returned by value or * not. Returns 1 if by value, 0 if by reference. * */ char get_typalign(Oid typid) { TypeTupleFormData typtup; if (SearchSysCacheStruct(TYPOID, (char *) &typtup, (char *) ObjectIdGetDatum(typid), (char *) NULL, (char *) NULL, (char *) NULL)) return(typtup.typalign); else return ('i'); } /* * get_typdefault - * * Given the type OID, return the default value of the ADT. * */ struct varlena * get_typdefault(Oid typid) { struct varlena *typdefault = (struct varlena *)TypeDefaultRetrieve (typid); return(typdefault); } /* * get_typtype - * * Given the type OID, find if it is a basic type, a named relation * or the generic type 'relation'. * It returns the null char if the cache lookup fails... * */ char get_typtype(Oid typid) { TypeTupleFormData typtup; if (SearchSysCacheStruct(TYPOID, (char *) &typtup, (char *) ObjectIdGetDatum(typid), (char *) NULL, (char *) NULL, (char *) NULL)) { return(typtup.typtype); } else { return('\0'); } }