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1534 lines
43 KiB
C
1534 lines
43 KiB
C
/*-------------------------------------------------------------------------
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*
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* parse_func.c
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* handle function calls in parser
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*
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* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.161 2003/09/29 00:05:25 petere Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/heapam.h"
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#include "catalog/catname.h"
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#include "catalog/pg_inherits.h"
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#include "catalog/pg_proc.h"
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#include "lib/stringinfo.h"
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#include "nodes/makefuncs.h"
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#include "parser/parse_agg.h"
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#include "parser/parse_coerce.h"
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#include "parser/parse_expr.h"
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#include "parser/parse_func.h"
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#include "parser/parse_relation.h"
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#include "parser/parse_type.h"
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#include "utils/builtins.h"
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#include "utils/fmgroids.h"
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#include "utils/lsyscache.h"
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#include "utils/syscache.h"
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static Node *ParseComplexProjection(char *funcname, Node *first_arg);
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static Oid **argtype_inherit(int nargs, Oid *argtypes);
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static int find_inheritors(Oid relid, Oid **supervec);
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static Oid **gen_cross_product(InhPaths *arginh, int nargs);
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static FieldSelect *setup_field_select(Node *input, char *attname, Oid relid);
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static void unknown_attribute(const char *schemaname, const char *relname,
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const char *attname);
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/*
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* Parse a function call
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*
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* For historical reasons, Postgres tries to treat the notations tab.col
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* and col(tab) as equivalent: if a single-argument function call has an
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* argument of complex type and the (unqualified) function name matches
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* any attribute of the type, we take it as a column projection.
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*
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* Hence, both cases come through here. The is_column parameter tells us
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* which syntactic construct is actually being dealt with, but this is
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* intended to be used only to deliver an appropriate error message,
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* not to affect the semantics. When is_column is true, we should have
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* a single argument (the putative table), unqualified function name
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* equal to the column name, and no aggregate decoration.
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*
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* In the function-call case, the argument expressions have been transformed
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* already. In the column case, we may get either a transformed expression
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* or a RangeVar node as argument.
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*/
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Node *
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ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
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bool agg_star, bool agg_distinct, bool is_column)
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{
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Oid rettype;
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Oid funcid;
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List *i;
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Node *first_arg = NULL;
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int nargs = length(fargs);
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int argn;
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Oid actual_arg_types[FUNC_MAX_ARGS];
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Oid *declared_arg_types;
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Node *retval;
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bool retset;
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FuncDetailCode fdresult;
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/*
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* Most of the rest of the parser just assumes that functions do not
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* have more than FUNC_MAX_ARGS parameters. We have to test here to
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* protect against array overruns, etc. Of course, this may not be a
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* function, but the test doesn't hurt.
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*/
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if (nargs > FUNC_MAX_ARGS)
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ereport(ERROR,
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(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
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errmsg("cannot pass more than %d arguments to a function",
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FUNC_MAX_ARGS)));
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if (fargs)
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{
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first_arg = lfirst(fargs);
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Assert(first_arg != NULL);
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}
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/*
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* check for column projection: if function has one argument, and that
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* argument is of complex type, and function name is not qualified,
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* then the "function call" could be a projection. We also check that
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* there wasn't any aggregate decoration.
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*/
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if (nargs == 1 && !agg_star && !agg_distinct && length(funcname) == 1)
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{
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char *cname = strVal(lfirst(funcname));
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/* Is it a not-yet-transformed RangeVar node? */
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if (IsA(first_arg, RangeVar))
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{
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/* First arg is a relation. This could be a projection. */
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retval = qualifiedNameToVar(pstate,
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((RangeVar *) first_arg)->schemaname,
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((RangeVar *) first_arg)->relname,
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cname,
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true);
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if (retval)
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return retval;
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}
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else if (ISCOMPLEX(exprType(first_arg)))
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{
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/*
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* Attempt to handle projection of a complex argument. If
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* ParseComplexProjection can't handle the projection, we have
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* to keep going.
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*/
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retval = ParseComplexProjection(cname, first_arg);
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if (retval)
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return retval;
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}
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}
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/*
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* Okay, it's not a column projection, so it must really be a
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* function. Extract arg type info and transform RangeVar arguments
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* into varnodes of the appropriate form.
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*/
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MemSet(actual_arg_types, 0, FUNC_MAX_ARGS * sizeof(Oid));
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argn = 0;
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foreach(i, fargs)
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{
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Node *arg = lfirst(i);
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Oid toid;
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if (IsA(arg, RangeVar))
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{
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char *schemaname;
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char *relname;
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RangeTblEntry *rte;
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int vnum;
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int sublevels_up;
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/*
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* a relation: look it up in the range table, or add if needed
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*/
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schemaname = ((RangeVar *) arg)->schemaname;
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relname = ((RangeVar *) arg)->relname;
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rte = refnameRangeTblEntry(pstate, schemaname, relname,
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&sublevels_up);
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if (rte == NULL)
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rte = addImplicitRTE(pstate, (RangeVar *) arg);
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vnum = RTERangeTablePosn(pstate, rte, &sublevels_up);
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/*
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* The parameter to be passed to the function is the whole
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* tuple from the relation. We build a special VarNode to
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* reflect this -- it has varno set to the correct range table
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* entry, but has varattno == 0 to signal that the whole tuple
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* is the argument. Also, it has typmod set to
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* sizeof(Pointer) to signal that the runtime representation
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* will be a pointer not an Oid.
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*/
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switch (rte->rtekind)
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{
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case RTE_RELATION:
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toid = get_rel_type_id(rte->relid);
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if (!OidIsValid(toid))
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elog(ERROR, "could not find type OID for relation %u",
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rte->relid);
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/* replace RangeVar in the arg list */
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lfirst(i) = makeVar(vnum,
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InvalidAttrNumber,
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toid,
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sizeof(Pointer),
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sublevels_up);
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break;
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case RTE_FUNCTION:
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toid = exprType(rte->funcexpr);
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if (get_typtype(toid) == 'c')
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{
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/* func returns composite; same as relation case */
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lfirst(i) = makeVar(vnum,
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InvalidAttrNumber,
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toid,
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sizeof(Pointer),
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sublevels_up);
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}
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else
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{
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/* func returns scalar; use attno 1 instead */
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lfirst(i) = makeVar(vnum,
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1,
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toid,
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-1,
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sublevels_up);
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}
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break;
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default:
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/*
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* RTE is a join or subselect; must fail for lack of a
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* named tuple type
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*/
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if (is_column)
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unknown_attribute(schemaname, relname,
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strVal(lfirst(funcname)));
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else
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("cannot pass result of subquery or join \"%s\" to a function",
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relname)));
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toid = InvalidOid; /* keep compiler quiet */
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break;
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}
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}
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else
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toid = exprType(arg);
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actual_arg_types[argn++] = toid;
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}
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/*
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* func_get_detail looks up the function in the catalogs, does
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* disambiguation for polymorphic functions, handles inheritance, and
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* returns the funcid and type and set or singleton status of the
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* function's return value. it also returns the true argument types
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* to the function.
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*/
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fdresult = func_get_detail(funcname, fargs, nargs, actual_arg_types,
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&funcid, &rettype, &retset,
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&declared_arg_types);
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if (fdresult == FUNCDETAIL_COERCION)
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{
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/*
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* We can do it as a trivial coercion. coerce_type can handle
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* these cases, so why duplicate code...
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*/
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return coerce_type(pstate, lfirst(fargs), actual_arg_types[0],
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rettype,
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COERCION_EXPLICIT, COERCE_EXPLICIT_CALL);
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}
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else if (fdresult == FUNCDETAIL_NORMAL)
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{
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/*
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* Normal function found; was there anything indicating it must be
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* an aggregate?
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*/
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if (agg_star)
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ereport(ERROR,
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(errcode(ERRCODE_WRONG_OBJECT_TYPE),
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errmsg("%s(*) specified, but %s is not an aggregate function",
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NameListToString(funcname),
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NameListToString(funcname))));
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if (agg_distinct)
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ereport(ERROR,
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(errcode(ERRCODE_WRONG_OBJECT_TYPE),
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errmsg("DISTINCT specified, but %s is not an aggregate function",
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NameListToString(funcname))));
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}
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else if (fdresult != FUNCDETAIL_AGGREGATE)
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{
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/*
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* Oops. Time to die.
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*
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* If we are dealing with the attribute notation rel.function, give
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* an error message that is appropriate for that case.
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*/
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if (is_column)
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{
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char *colname = strVal(lfirst(funcname));
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Oid relTypeId;
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Assert(nargs == 1);
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if (IsA(first_arg, RangeVar))
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unknown_attribute(((RangeVar *) first_arg)->schemaname,
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((RangeVar *) first_arg)->relname,
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colname);
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relTypeId = exprType(first_arg);
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if (!ISCOMPLEX(relTypeId))
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ereport(ERROR,
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(errcode(ERRCODE_WRONG_OBJECT_TYPE),
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errmsg("attribute notation .%s applied to type %s, which is not a complex type",
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colname, format_type_be(relTypeId))));
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else
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ereport(ERROR,
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(errcode(ERRCODE_UNDEFINED_COLUMN),
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errmsg("attribute \"%s\" not found in data type %s",
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colname, format_type_be(relTypeId))));
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}
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/*
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* Else generate a detailed complaint for a function
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*/
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if (fdresult == FUNCDETAIL_MULTIPLE)
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ereport(ERROR,
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(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
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errmsg("function %s is not unique",
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func_signature_string(funcname, nargs,
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actual_arg_types)),
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errhint("Could not choose a best candidate function. "
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"You may need to add explicit type casts.")));
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else
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ereport(ERROR,
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(errcode(ERRCODE_UNDEFINED_FUNCTION),
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errmsg("function %s does not exist",
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func_signature_string(funcname, nargs,
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actual_arg_types)),
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errhint("No function matches the given name and argument types. "
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"You may need to add explicit type casts.")));
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}
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/*
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* enforce consistency with ANYARRAY and ANYELEMENT argument and
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* return types, possibly adjusting return type or declared_arg_types
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* (which will be used as the cast destination by make_fn_arguments)
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*/
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rettype = enforce_generic_type_consistency(actual_arg_types,
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declared_arg_types,
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nargs,
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rettype);
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/* perform the necessary typecasting of arguments */
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make_fn_arguments(pstate, fargs, actual_arg_types, declared_arg_types);
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/* build the appropriate output structure */
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if (fdresult == FUNCDETAIL_NORMAL)
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{
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FuncExpr *funcexpr = makeNode(FuncExpr);
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funcexpr->funcid = funcid;
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funcexpr->funcresulttype = rettype;
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funcexpr->funcretset = retset;
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funcexpr->funcformat = COERCE_EXPLICIT_CALL;
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funcexpr->args = fargs;
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retval = (Node *) funcexpr;
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}
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else
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{
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/* aggregate function */
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Aggref *aggref = makeNode(Aggref);
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aggref->aggfnoid = funcid;
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aggref->aggtype = rettype;
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aggref->target = lfirst(fargs);
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aggref->aggstar = agg_star;
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aggref->aggdistinct = agg_distinct;
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/* parse_agg.c does additional aggregate-specific processing */
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transformAggregateCall(pstate, aggref);
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retval = (Node *) aggref;
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if (retset)
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ereport(ERROR,
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(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
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errmsg("aggregates may not return sets")));
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}
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return retval;
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}
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/* func_match_argtypes()
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*
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* Given a list of candidate functions (having the right name and number
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* of arguments) and an array of input datatype OIDs, produce a shortlist of
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* those candidates that actually accept the input datatypes (either exactly
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* or by coercion), and return the number of such candidates.
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*
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* Note that can_coerce_type will assume that UNKNOWN inputs are coercible to
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* anything, so candidates will not be eliminated on that basis.
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*
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* NB: okay to modify input list structure, as long as we find at least
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* one match. If no match at all, the list must remain unmodified.
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*/
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int
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func_match_argtypes(int nargs,
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Oid *input_typeids,
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FuncCandidateList raw_candidates,
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FuncCandidateList *candidates) /* return value */
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{
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FuncCandidateList current_candidate;
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FuncCandidateList next_candidate;
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int ncandidates = 0;
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*candidates = NULL;
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for (current_candidate = raw_candidates;
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current_candidate != NULL;
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current_candidate = next_candidate)
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{
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next_candidate = current_candidate->next;
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if (can_coerce_type(nargs, input_typeids, current_candidate->args,
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COERCION_IMPLICIT))
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{
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current_candidate->next = *candidates;
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*candidates = current_candidate;
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ncandidates++;
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}
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}
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return ncandidates;
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} /* func_match_argtypes() */
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/* func_select_candidate()
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* Given the input argtype array and more than one candidate
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* for the function, attempt to resolve the conflict.
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*
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* Returns the selected candidate if the conflict can be resolved,
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* otherwise returns NULL.
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*
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* Note that the caller has already determined that there is no candidate
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* exactly matching the input argtypes, and has pruned away any "candidates"
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* that aren't actually coercion-compatible with the input types.
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*
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* This is also used for resolving ambiguous operator references. Formerly
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* parse_oper.c had its own, essentially duplicate code for the purpose.
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* The following comments (formerly in parse_oper.c) are kept to record some
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* of the history of these heuristics.
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*
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* OLD COMMENTS:
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*
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* This routine is new code, replacing binary_oper_select_candidate()
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* which dates from v4.2/v1.0.x days. It tries very hard to match up
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* operators with types, including allowing type coercions if necessary.
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* The important thing is that the code do as much as possible,
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* while _never_ doing the wrong thing, where "the wrong thing" would
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* be returning an operator when other better choices are available,
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* or returning an operator which is a non-intuitive possibility.
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* - thomas 1998-05-21
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*
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* The comments below came from binary_oper_select_candidate(), and
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* illustrate the issues and choices which are possible:
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* - thomas 1998-05-20
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*
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* current wisdom holds that the default operator should be one in which
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* both operands have the same type (there will only be one such
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* operator)
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*
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* 7.27.93 - I have decided not to do this; it's too hard to justify, and
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* it's easy enough to typecast explicitly - avi
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* [the rest of this routine was commented out since then - ay]
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*
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* 6/23/95 - I don't complete agree with avi. In particular, casting
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* floats is a pain for users. Whatever the rationale behind not doing
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* this is, I need the following special case to work.
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*
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* In the WHERE clause of a query, if a float is specified without
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* quotes, we treat it as float8. I added the float48* operators so
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* that we can operate on float4 and float8. But now we have more than
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* one matching operator if the right arg is unknown (eg. float
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* specified with quotes). This break some stuff in the regression
|
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* test where there are floats in quotes not properly casted. Below is
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* the solution. In addition to requiring the operator operates on the
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* same type for both operands [as in the code Avi originally
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* commented out], we also require that the operators be equivalent in
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* some sense. (see equivalentOpersAfterPromotion for details.)
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* - ay 6/95
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*/
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FuncCandidateList
|
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func_select_candidate(int nargs,
|
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Oid *input_typeids,
|
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FuncCandidateList candidates)
|
|
{
|
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FuncCandidateList current_candidate;
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FuncCandidateList last_candidate;
|
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Oid *current_typeids;
|
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Oid current_type;
|
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int i;
|
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int ncandidates;
|
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int nbestMatch,
|
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nmatch;
|
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Oid input_base_typeids[FUNC_MAX_ARGS];
|
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CATEGORY slot_category[FUNC_MAX_ARGS],
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current_category;
|
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bool slot_has_preferred_type[FUNC_MAX_ARGS];
|
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bool resolved_unknowns;
|
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|
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/*
|
|
* If any input types are domains, reduce them to their base types.
|
|
* This ensures that we will consider functions on the base type to be
|
|
* "exact matches" in the exact-match heuristic; it also makes it
|
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* possible to do something useful with the type-category heuristics.
|
|
* Note that this makes it difficult, but not impossible, to use
|
|
* functions declared to take a domain as an input datatype. Such a
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* function will be selected over the base-type function only if it is
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* an exact match at all argument positions, and so was already chosen
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* by our caller.
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*/
|
|
for (i = 0; i < nargs; i++)
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input_base_typeids[i] = getBaseType(input_typeids[i]);
|
|
|
|
/*
|
|
* Run through all candidates and keep those with the most matches on
|
|
* exact types. Keep all candidates if none match.
|
|
*/
|
|
ncandidates = 0;
|
|
nbestMatch = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
nmatch = 0;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_base_typeids[i] != UNKNOWNOID &&
|
|
current_typeids[i] == input_base_typeids[i])
|
|
nmatch++;
|
|
}
|
|
|
|
/* take this one as the best choice so far? */
|
|
if ((nmatch > nbestMatch) || (last_candidate == NULL))
|
|
{
|
|
nbestMatch = nmatch;
|
|
candidates = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates = 1;
|
|
}
|
|
/* no worse than the last choice, so keep this one too? */
|
|
else if (nmatch == nbestMatch)
|
|
{
|
|
last_candidate->next = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
/* otherwise, don't bother keeping this one... */
|
|
}
|
|
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
|
|
if (ncandidates == 1)
|
|
return candidates;
|
|
|
|
/*
|
|
* Still too many candidates? Now look for candidates which have
|
|
* either exact matches or preferred types at the args that will
|
|
* require coercion. (Restriction added in 7.4: preferred type must be
|
|
* of same category as input type; give no preference to
|
|
* cross-category conversions to preferred types.) Keep all
|
|
* candidates if none match.
|
|
*/
|
|
for (i = 0; i < nargs; i++) /* avoid multiple lookups */
|
|
slot_category[i] = TypeCategory(input_base_typeids[i]);
|
|
ncandidates = 0;
|
|
nbestMatch = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
nmatch = 0;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_base_typeids[i] != UNKNOWNOID)
|
|
{
|
|
if (current_typeids[i] == input_base_typeids[i] ||
|
|
IsPreferredType(slot_category[i], current_typeids[i]))
|
|
nmatch++;
|
|
}
|
|
}
|
|
|
|
if ((nmatch > nbestMatch) || (last_candidate == NULL))
|
|
{
|
|
nbestMatch = nmatch;
|
|
candidates = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates = 1;
|
|
}
|
|
else if (nmatch == nbestMatch)
|
|
{
|
|
last_candidate->next = current_candidate;
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
}
|
|
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
|
|
if (ncandidates == 1)
|
|
return candidates;
|
|
|
|
/*
|
|
* Still too many candidates? Try assigning types for the unknown
|
|
* columns.
|
|
*
|
|
* NOTE: for a binary operator with one unknown and one non-unknown
|
|
* input, we already tried the heuristic of looking for a candidate
|
|
* with the known input type on both sides (see binary_oper_exact()).
|
|
* That's essentially a special case of the general algorithm we try
|
|
* next.
|
|
*
|
|
* We do this by examining each unknown argument position to see if we
|
|
* can determine a "type category" for it. If any candidate has an
|
|
* input datatype of STRING category, use STRING category (this bias
|
|
* towards STRING is appropriate since unknown-type literals look like
|
|
* strings). Otherwise, if all the candidates agree on the type
|
|
* category of this argument position, use that category. Otherwise,
|
|
* fail because we cannot determine a category.
|
|
*
|
|
* If we are able to determine a type category, also notice whether any
|
|
* of the candidates takes a preferred datatype within the category.
|
|
*
|
|
* Having completed this examination, remove candidates that accept the
|
|
* wrong category at any unknown position. Also, if at least one
|
|
* candidate accepted a preferred type at a position, remove
|
|
* candidates that accept non-preferred types.
|
|
*
|
|
* If we are down to one candidate at the end, we win.
|
|
*/
|
|
resolved_unknowns = false;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
bool have_conflict;
|
|
|
|
if (input_base_typeids[i] != UNKNOWNOID)
|
|
continue;
|
|
resolved_unknowns = true; /* assume we can do it */
|
|
slot_category[i] = INVALID_TYPE;
|
|
slot_has_preferred_type[i] = false;
|
|
have_conflict = false;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
current_typeids = current_candidate->args;
|
|
current_type = current_typeids[i];
|
|
current_category = TypeCategory(current_type);
|
|
if (slot_category[i] == INVALID_TYPE)
|
|
{
|
|
/* first candidate */
|
|
slot_category[i] = current_category;
|
|
slot_has_preferred_type[i] =
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else if (current_category == slot_category[i])
|
|
{
|
|
/* more candidates in same category */
|
|
slot_has_preferred_type[i] |=
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else
|
|
{
|
|
/* category conflict! */
|
|
if (current_category == STRING_TYPE)
|
|
{
|
|
/* STRING always wins if available */
|
|
slot_category[i] = current_category;
|
|
slot_has_preferred_type[i] =
|
|
IsPreferredType(current_category, current_type);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Remember conflict, but keep going (might find
|
|
* STRING)
|
|
*/
|
|
have_conflict = true;
|
|
}
|
|
}
|
|
}
|
|
if (have_conflict && slot_category[i] != STRING_TYPE)
|
|
{
|
|
/* Failed to resolve category conflict at this position */
|
|
resolved_unknowns = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (resolved_unknowns)
|
|
{
|
|
/* Strip non-matching candidates */
|
|
ncandidates = 0;
|
|
last_candidate = NULL;
|
|
for (current_candidate = candidates;
|
|
current_candidate != NULL;
|
|
current_candidate = current_candidate->next)
|
|
{
|
|
bool keepit = true;
|
|
|
|
current_typeids = current_candidate->args;
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (input_base_typeids[i] != UNKNOWNOID)
|
|
continue;
|
|
current_type = current_typeids[i];
|
|
current_category = TypeCategory(current_type);
|
|
if (current_category != slot_category[i])
|
|
{
|
|
keepit = false;
|
|
break;
|
|
}
|
|
if (slot_has_preferred_type[i] &&
|
|
!IsPreferredType(current_category, current_type))
|
|
{
|
|
keepit = false;
|
|
break;
|
|
}
|
|
}
|
|
if (keepit)
|
|
{
|
|
/* keep this candidate */
|
|
last_candidate = current_candidate;
|
|
ncandidates++;
|
|
}
|
|
else
|
|
{
|
|
/* forget this candidate */
|
|
if (last_candidate)
|
|
last_candidate->next = current_candidate->next;
|
|
else
|
|
candidates = current_candidate->next;
|
|
}
|
|
}
|
|
if (last_candidate) /* terminate rebuilt list */
|
|
last_candidate->next = NULL;
|
|
}
|
|
|
|
if (ncandidates == 1)
|
|
return candidates;
|
|
|
|
return NULL; /* failed to select a best candidate */
|
|
} /* func_select_candidate() */
|
|
|
|
|
|
/* func_get_detail()
|
|
*
|
|
* Find the named function in the system catalogs.
|
|
*
|
|
* Attempt to find the named function in the system catalogs with
|
|
* arguments exactly as specified, so that the normal case
|
|
* (exact match) is as quick as possible.
|
|
*
|
|
* If an exact match isn't found:
|
|
* 1) check for possible interpretation as a trivial type coercion
|
|
* 2) get a vector of all possible input arg type arrays constructed
|
|
* from the superclasses of the original input arg types
|
|
* 3) get a list of all possible argument type arrays to the function
|
|
* with given name and number of arguments
|
|
* 4) for each input arg type array from vector #1:
|
|
* a) find how many of the function arg type arrays from list #2
|
|
* it can be coerced to
|
|
* b) if the answer is one, we have our function
|
|
* c) if the answer is more than one, attempt to resolve the conflict
|
|
* d) if the answer is zero, try the next array from vector #1
|
|
*
|
|
* Note: we rely primarily on nargs/argtypes as the argument description.
|
|
* The actual expression node list is passed in fargs so that we can check
|
|
* for type coercion of a constant. Some callers pass fargs == NIL
|
|
* indicating they don't want that check made.
|
|
*/
|
|
FuncDetailCode
|
|
func_get_detail(List *funcname,
|
|
List *fargs,
|
|
int nargs,
|
|
Oid *argtypes,
|
|
Oid *funcid, /* return value */
|
|
Oid *rettype, /* return value */
|
|
bool *retset, /* return value */
|
|
Oid **true_typeids) /* return value */
|
|
{
|
|
FuncCandidateList raw_candidates;
|
|
FuncCandidateList best_candidate;
|
|
|
|
/* Get list of possible candidates from namespace search */
|
|
raw_candidates = FuncnameGetCandidates(funcname, nargs);
|
|
|
|
/*
|
|
* Quickly check if there is an exact match to the input datatypes
|
|
* (there can be only one)
|
|
*/
|
|
for (best_candidate = raw_candidates;
|
|
best_candidate != NULL;
|
|
best_candidate = best_candidate->next)
|
|
{
|
|
if (memcmp(argtypes, best_candidate->args, nargs * sizeof(Oid)) == 0)
|
|
break;
|
|
}
|
|
|
|
if (best_candidate == NULL)
|
|
{
|
|
/*
|
|
* If we didn't find an exact match, next consider the possibility
|
|
* that this is really a type-coercion request: a single-argument
|
|
* function call where the function name is a type name. If so,
|
|
* and if we can do the coercion trivially (no run-time function
|
|
* call needed), then go ahead and treat the "function call" as a
|
|
* coercion. This interpretation needs to be given higher
|
|
* priority than interpretations involving a type coercion
|
|
* followed by a function call, otherwise we can produce
|
|
* surprising results. For example, we want "text(varchar)" to be
|
|
* interpreted as a trivial coercion, not as "text(name(varchar))"
|
|
* which the code below this point is entirely capable of
|
|
* selecting.
|
|
*
|
|
* "Trivial" coercions are ones that involve binary-compatible types
|
|
* and ones that are coercing a previously-unknown-type literal
|
|
* constant to a specific type.
|
|
*
|
|
* The reason we can restrict our check to binary-compatible
|
|
* coercions here is that we expect non-binary-compatible
|
|
* coercions to have an implementation function named after the
|
|
* target type. That function will be found by normal lookup if
|
|
* appropriate.
|
|
*
|
|
* NB: it's important that this code stays in sync with what
|
|
* coerce_type can do, because the caller will try to apply
|
|
* coerce_type if we return FUNCDETAIL_COERCION. If we return
|
|
* that result for something coerce_type can't handle, we'll cause
|
|
* infinite recursion between this module and coerce_type!
|
|
*/
|
|
if (nargs == 1 && fargs != NIL)
|
|
{
|
|
Oid targetType;
|
|
TypeName *tn = makeNode(TypeName);
|
|
|
|
tn->names = funcname;
|
|
tn->typmod = -1;
|
|
targetType = LookupTypeName(tn);
|
|
if (OidIsValid(targetType) &&
|
|
!ISCOMPLEX(targetType))
|
|
{
|
|
Oid sourceType = argtypes[0];
|
|
Node *arg1 = lfirst(fargs);
|
|
|
|
if ((sourceType == UNKNOWNOID && IsA(arg1, Const)) ||
|
|
(find_coercion_pathway(targetType, sourceType,
|
|
COERCION_EXPLICIT, funcid) &&
|
|
*funcid == InvalidOid))
|
|
{
|
|
/* Yup, it's a type coercion */
|
|
*funcid = InvalidOid;
|
|
*rettype = targetType;
|
|
*retset = false;
|
|
*true_typeids = argtypes;
|
|
return FUNCDETAIL_COERCION;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* didn't find an exact match, so now try to match up
|
|
* candidates...
|
|
*/
|
|
if (raw_candidates != NULL)
|
|
{
|
|
Oid **input_typeid_vector = NULL;
|
|
Oid *current_input_typeids;
|
|
|
|
/*
|
|
* First we will search with the given argtypes, then with
|
|
* variants based on replacing complex types with their
|
|
* inheritance ancestors. Stop as soon as any match is found.
|
|
*/
|
|
current_input_typeids = argtypes;
|
|
|
|
do
|
|
{
|
|
FuncCandidateList current_candidates;
|
|
int ncandidates;
|
|
|
|
ncandidates = func_match_argtypes(nargs,
|
|
current_input_typeids,
|
|
raw_candidates,
|
|
¤t_candidates);
|
|
|
|
/* one match only? then run with it... */
|
|
if (ncandidates == 1)
|
|
{
|
|
best_candidate = current_candidates;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* multiple candidates? then better decide or throw an
|
|
* error...
|
|
*/
|
|
if (ncandidates > 1)
|
|
{
|
|
best_candidate = func_select_candidate(nargs,
|
|
current_input_typeids,
|
|
current_candidates);
|
|
|
|
/*
|
|
* If we were able to choose a best candidate, we're
|
|
* done. Otherwise, ambiguous function call.
|
|
*/
|
|
if (best_candidate)
|
|
break;
|
|
return FUNCDETAIL_MULTIPLE;
|
|
}
|
|
|
|
/*
|
|
* No match here, so try the next inherited type vector.
|
|
* First time through, we need to compute the list of
|
|
* vectors.
|
|
*/
|
|
if (input_typeid_vector == NULL)
|
|
input_typeid_vector = argtype_inherit(nargs, argtypes);
|
|
|
|
current_input_typeids = *input_typeid_vector++;
|
|
}
|
|
while (current_input_typeids != NULL);
|
|
}
|
|
}
|
|
|
|
if (best_candidate)
|
|
{
|
|
HeapTuple ftup;
|
|
Form_pg_proc pform;
|
|
FuncDetailCode result;
|
|
|
|
*funcid = best_candidate->oid;
|
|
*true_typeids = best_candidate->args;
|
|
|
|
ftup = SearchSysCache(PROCOID,
|
|
ObjectIdGetDatum(best_candidate->oid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(ftup)) /* should not happen */
|
|
elog(ERROR, "cache lookup failed for function %u",
|
|
best_candidate->oid);
|
|
pform = (Form_pg_proc) GETSTRUCT(ftup);
|
|
*rettype = pform->prorettype;
|
|
*retset = pform->proretset;
|
|
result = pform->proisagg ? FUNCDETAIL_AGGREGATE : FUNCDETAIL_NORMAL;
|
|
ReleaseSysCache(ftup);
|
|
return result;
|
|
}
|
|
|
|
return FUNCDETAIL_NOTFOUND;
|
|
}
|
|
|
|
/*
|
|
* argtype_inherit() -- Construct an argtype vector reflecting the
|
|
* inheritance properties of the supplied argv.
|
|
*
|
|
* This function is used to handle resolution of function calls when
|
|
* there is no match to the given argument types, but there might be
|
|
* matches based on considering complex types as members of their
|
|
* superclass types (parent classes).
|
|
*
|
|
* It takes an array of input type ids. For each type id in the array
|
|
* that's a complex type (a class), it walks up the inheritance tree,
|
|
* finding all superclasses of that type. A vector of new Oid type
|
|
* arrays is returned to the caller, listing possible alternative
|
|
* interpretations of the input typeids as members of their superclasses
|
|
* rather than the actually given argument types. The vector is
|
|
* terminated by a NULL pointer.
|
|
*
|
|
* The order of this vector is as follows: all superclasses of the
|
|
* rightmost complex class are explored first. The exploration
|
|
* continues from right to left. This policy means that we favor
|
|
* keeping the leftmost argument type as low in the inheritance tree
|
|
* as possible. This is intentional; it is exactly what we need to
|
|
* do for method dispatch.
|
|
*
|
|
* The vector does not include the case where no complex classes have
|
|
* been promoted, since that was already tried before this routine
|
|
* got called.
|
|
*/
|
|
static Oid **
|
|
argtype_inherit(int nargs, Oid *argtypes)
|
|
{
|
|
Oid relid;
|
|
int i;
|
|
InhPaths arginh[FUNC_MAX_ARGS];
|
|
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
arginh[i].self = argtypes[i];
|
|
if ((relid = typeidTypeRelid(argtypes[i])) != InvalidOid)
|
|
arginh[i].nsupers = find_inheritors(relid, &(arginh[i].supervec));
|
|
else
|
|
{
|
|
arginh[i].nsupers = 0;
|
|
arginh[i].supervec = (Oid *) NULL;
|
|
}
|
|
}
|
|
|
|
/* return an ordered cross-product of the classes involved */
|
|
return gen_cross_product(arginh, nargs);
|
|
}
|
|
|
|
/*
|
|
* Look up the parent superclass(es) of the given relation.
|
|
*
|
|
* *supervec is set to an array of the type OIDs (not the relation OIDs)
|
|
* of the parents, with nearest ancestors listed first. It's set to NULL
|
|
* if there are no parents. The return value is the number of parents.
|
|
*/
|
|
static int
|
|
find_inheritors(Oid relid, Oid **supervec)
|
|
{
|
|
Relation inhrel;
|
|
HeapScanDesc inhscan;
|
|
ScanKeyData skey;
|
|
HeapTuple inhtup;
|
|
Oid *relidvec;
|
|
int nvisited;
|
|
List *visited,
|
|
*queue;
|
|
List *elt;
|
|
bool newrelid;
|
|
|
|
nvisited = 0;
|
|
queue = NIL;
|
|
visited = NIL;
|
|
|
|
inhrel = heap_openr(InheritsRelationName, AccessShareLock);
|
|
|
|
/*
|
|
* Use queue to do a breadth-first traversal of the inheritance graph
|
|
* from the relid supplied up to the root. At the top of the loop,
|
|
* relid is the OID of the reltype to check next, queue is the list of
|
|
* pending relids to check after this one, and visited is the list of
|
|
* relids we need to output.
|
|
*/
|
|
do
|
|
{
|
|
/* find all types this relid inherits from, and add them to queue */
|
|
|
|
ScanKeyEntryInitialize(&skey, 0x0, Anum_pg_inherits_inhrelid,
|
|
F_OIDEQ,
|
|
ObjectIdGetDatum(relid));
|
|
|
|
inhscan = heap_beginscan(inhrel, SnapshotNow, 1, &skey);
|
|
|
|
while ((inhtup = heap_getnext(inhscan, ForwardScanDirection)) != NULL)
|
|
{
|
|
Form_pg_inherits inh = (Form_pg_inherits) GETSTRUCT(inhtup);
|
|
|
|
queue = lappendo(queue, inh->inhparent);
|
|
}
|
|
|
|
heap_endscan(inhscan);
|
|
|
|
/* pull next unvisited relid off the queue */
|
|
|
|
newrelid = false;
|
|
while (queue != NIL)
|
|
{
|
|
relid = lfirsto(queue);
|
|
queue = lnext(queue);
|
|
if (!oidMember(relid, visited))
|
|
{
|
|
newrelid = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (newrelid)
|
|
{
|
|
visited = lappendo(visited, relid);
|
|
nvisited++;
|
|
}
|
|
} while (newrelid);
|
|
|
|
heap_close(inhrel, AccessShareLock);
|
|
|
|
if (nvisited > 0)
|
|
{
|
|
relidvec = (Oid *) palloc(nvisited * sizeof(Oid));
|
|
*supervec = relidvec;
|
|
|
|
foreach(elt, visited)
|
|
{
|
|
/* return the type id, rather than the relation id */
|
|
*relidvec++ = get_rel_type_id(lfirsto(elt));
|
|
}
|
|
}
|
|
else
|
|
*supervec = (Oid *) NULL;
|
|
|
|
freeList(visited);
|
|
|
|
/*
|
|
* there doesn't seem to be any equally easy way to release the queue
|
|
* list cells, but since they're palloc'd space it's not critical.
|
|
*/
|
|
|
|
return nvisited;
|
|
}
|
|
|
|
/*
|
|
* Generate the ordered list of substitute argtype vectors to try.
|
|
*
|
|
* See comments for argtype_inherit.
|
|
*/
|
|
static Oid **
|
|
gen_cross_product(InhPaths *arginh, int nargs)
|
|
{
|
|
int nanswers;
|
|
Oid **result;
|
|
Oid *oneres;
|
|
int i,
|
|
j;
|
|
int cur[FUNC_MAX_ARGS];
|
|
|
|
/*
|
|
* At each position we want to try the original datatype, plus each
|
|
* supertype. So the number of possible combinations is this:
|
|
*/
|
|
nanswers = 1;
|
|
for (i = 0; i < nargs; i++)
|
|
nanswers *= (arginh[i].nsupers + 1);
|
|
|
|
/*
|
|
* We also need an extra slot for the terminating NULL in the result
|
|
* array, but that cancels out with the fact that we don't want to
|
|
* generate the zero-changes case. So we need exactly nanswers slots.
|
|
*/
|
|
result = (Oid **) palloc(sizeof(Oid *) * nanswers);
|
|
j = 0;
|
|
|
|
/*
|
|
* Compute the cross product from right to left. When cur[i] == 0,
|
|
* generate the original input type at position i. When cur[i] == k
|
|
* for k > 0, generate its k'th supertype.
|
|
*/
|
|
MemSet(cur, 0, sizeof(cur));
|
|
|
|
for (;;)
|
|
{
|
|
/*
|
|
* Find a column we can increment. All the columns after it get
|
|
* reset to zero. (Essentially, we're adding one to the multi-
|
|
* digit number represented by cur[].)
|
|
*/
|
|
for (i = nargs - 1; i >= 0 && cur[i] >= arginh[i].nsupers; i--)
|
|
cur[i] = 0;
|
|
|
|
/* if none, we're done */
|
|
if (i < 0)
|
|
break;
|
|
|
|
/* increment this column */
|
|
cur[i] += 1;
|
|
|
|
/* Generate the proper output type-OID vector */
|
|
oneres = (Oid *) palloc0(FUNC_MAX_ARGS * sizeof(Oid));
|
|
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (cur[i] == 0)
|
|
oneres[i] = arginh[i].self;
|
|
else
|
|
oneres[i] = arginh[i].supervec[cur[i] - 1];
|
|
}
|
|
|
|
result[j++] = oneres;
|
|
}
|
|
|
|
/* terminate result vector with NULL pointer */
|
|
result[j++] = NULL;
|
|
|
|
Assert(j == nanswers);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* Given two type OIDs, determine whether the first is a complex type
|
|
* (class type) that inherits from the second.
|
|
*/
|
|
bool
|
|
typeInheritsFrom(Oid subclassTypeId, Oid superclassTypeId)
|
|
{
|
|
Oid relid;
|
|
Oid *supervec;
|
|
int nsupers,
|
|
i;
|
|
bool result;
|
|
|
|
if (!ISCOMPLEX(subclassTypeId) || !ISCOMPLEX(superclassTypeId))
|
|
return false;
|
|
relid = typeidTypeRelid(subclassTypeId);
|
|
if (relid == InvalidOid)
|
|
return false;
|
|
nsupers = find_inheritors(relid, &supervec);
|
|
result = false;
|
|
for (i = 0; i < nsupers; i++)
|
|
{
|
|
if (supervec[i] == superclassTypeId)
|
|
{
|
|
result = true;
|
|
break;
|
|
}
|
|
}
|
|
if (supervec)
|
|
pfree(supervec);
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* make_fn_arguments()
|
|
*
|
|
* Given the actual argument expressions for a function, and the desired
|
|
* input types for the function, add any necessary typecasting to the
|
|
* expression tree. Caller should already have verified that casting is
|
|
* allowed.
|
|
*
|
|
* Caution: given argument list is modified in-place.
|
|
*
|
|
* As with coerce_type, pstate may be NULL if no special unknown-Param
|
|
* processing is wanted.
|
|
*/
|
|
void
|
|
make_fn_arguments(ParseState *pstate,
|
|
List *fargs,
|
|
Oid *actual_arg_types,
|
|
Oid *declared_arg_types)
|
|
{
|
|
List *current_fargs;
|
|
int i = 0;
|
|
|
|
foreach(current_fargs, fargs)
|
|
{
|
|
/* types don't match? then force coercion using a function call... */
|
|
if (actual_arg_types[i] != declared_arg_types[i])
|
|
{
|
|
lfirst(current_fargs) = coerce_type(pstate,
|
|
lfirst(current_fargs),
|
|
actual_arg_types[i],
|
|
declared_arg_types[i],
|
|
COERCION_IMPLICIT,
|
|
COERCE_IMPLICIT_CAST);
|
|
}
|
|
i++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* setup_field_select
|
|
* Build a FieldSelect node that says which attribute to project to.
|
|
* This routine is called by ParseFuncOrColumn() when we have found
|
|
* a projection on a function result or parameter.
|
|
*/
|
|
static FieldSelect *
|
|
setup_field_select(Node *input, char *attname, Oid relid)
|
|
{
|
|
FieldSelect *fselect = makeNode(FieldSelect);
|
|
AttrNumber attno;
|
|
|
|
attno = get_attnum(relid, attname);
|
|
if (attno == InvalidAttrNumber)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column \"%s\" of relation \"%s\" does not exist",
|
|
attname, get_rel_name(relid))));
|
|
|
|
fselect->arg = (Expr *) input;
|
|
fselect->fieldnum = attno;
|
|
fselect->resulttype = get_atttype(relid, attno);
|
|
fselect->resulttypmod = get_atttypmod(relid, attno);
|
|
|
|
return fselect;
|
|
}
|
|
|
|
/*
|
|
* ParseComplexProjection -
|
|
* handles function calls with a single argument that is of complex type.
|
|
* If the function call is actually a column projection, return a suitably
|
|
* transformed expression tree. If not, return NULL.
|
|
*
|
|
* NB: argument is expected to be transformed already, ie, not a RangeVar.
|
|
*/
|
|
static Node *
|
|
ParseComplexProjection(char *funcname, Node *first_arg)
|
|
{
|
|
Oid argtype = exprType(first_arg);
|
|
Oid argrelid;
|
|
AttrNumber attnum;
|
|
FieldSelect *fselect;
|
|
|
|
argrelid = typeidTypeRelid(argtype);
|
|
if (!argrelid)
|
|
return NULL; /* probably should not happen */
|
|
attnum = get_attnum(argrelid, funcname);
|
|
if (attnum == InvalidAttrNumber)
|
|
return NULL; /* funcname does not match any column */
|
|
|
|
/*
|
|
* Check for special cases where we don't want to return a
|
|
* FieldSelect.
|
|
*/
|
|
switch (nodeTag(first_arg))
|
|
{
|
|
case T_Var:
|
|
{
|
|
Var *var = (Var *) first_arg;
|
|
|
|
/*
|
|
* If the Var is a whole-row tuple, we can just replace it
|
|
* with a simple Var reference.
|
|
*/
|
|
if (var->varattno == InvalidAttrNumber)
|
|
{
|
|
Oid vartype;
|
|
int32 vartypmod;
|
|
|
|
get_atttypetypmod(argrelid, attnum,
|
|
&vartype, &vartypmod);
|
|
|
|
return (Node *) makeVar(var->varno,
|
|
attnum,
|
|
vartype,
|
|
vartypmod,
|
|
var->varlevelsup);
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
/* Else generate a FieldSelect expression */
|
|
fselect = setup_field_select(first_arg, funcname, argrelid);
|
|
return (Node *) fselect;
|
|
}
|
|
|
|
/*
|
|
* Simple helper routine for delivering "column does not exist" error message
|
|
*/
|
|
static void
|
|
unknown_attribute(const char *schemaname, const char *relname,
|
|
const char *attname)
|
|
{
|
|
if (schemaname)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column %s.%s.%s does not exist",
|
|
schemaname, relname, attname)));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column %s.%s does not exist",
|
|
relname, attname)));
|
|
}
|
|
|
|
/*
|
|
* funcname_signature_string
|
|
* Build a string representing a function name, including arg types.
|
|
* The result is something like "foo(integer)".
|
|
*
|
|
* This is typically used in the construction of function-not-found error
|
|
* messages.
|
|
*/
|
|
const char *
|
|
funcname_signature_string(const char *funcname,
|
|
int nargs, const Oid *argtypes)
|
|
{
|
|
StringInfoData argbuf;
|
|
int i;
|
|
|
|
initStringInfo(&argbuf);
|
|
|
|
appendStringInfo(&argbuf, "%s(", funcname);
|
|
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
if (i)
|
|
appendStringInfoString(&argbuf, ", ");
|
|
appendStringInfoString(&argbuf, format_type_be(argtypes[i]));
|
|
}
|
|
|
|
appendStringInfoChar(&argbuf, ')');
|
|
|
|
return argbuf.data; /* return palloc'd string buffer */
|
|
}
|
|
|
|
/*
|
|
* func_signature_string
|
|
* As above, but function name is passed as a qualified name list.
|
|
*/
|
|
const char *
|
|
func_signature_string(List *funcname, int nargs, const Oid *argtypes)
|
|
{
|
|
return funcname_signature_string(NameListToString(funcname),
|
|
nargs, argtypes);
|
|
}
|
|
|
|
/*
|
|
* find_aggregate_func
|
|
* Convenience routine to check that a function exists and is an
|
|
* aggregate.
|
|
*
|
|
* Note: basetype is ANYOID if we are looking for an aggregate on
|
|
* all types.
|
|
*/
|
|
Oid
|
|
find_aggregate_func(List *aggname, Oid basetype, bool noError)
|
|
{
|
|
Oid oid;
|
|
HeapTuple ftup;
|
|
Form_pg_proc pform;
|
|
|
|
oid = LookupFuncName(aggname, 1, &basetype, true);
|
|
|
|
if (!OidIsValid(oid))
|
|
{
|
|
if (noError)
|
|
return InvalidOid;
|
|
if (basetype == ANYOID)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_FUNCTION),
|
|
errmsg("aggregate %s(*) does not exist",
|
|
NameListToString(aggname))));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_FUNCTION),
|
|
errmsg("aggregate %s(%s) does not exist",
|
|
NameListToString(aggname),
|
|
format_type_be(basetype))));
|
|
}
|
|
|
|
/* Make sure it's an aggregate */
|
|
ftup = SearchSysCache(PROCOID,
|
|
ObjectIdGetDatum(oid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(ftup)) /* should not happen */
|
|
elog(ERROR, "cache lookup failed for function %u", oid);
|
|
pform = (Form_pg_proc) GETSTRUCT(ftup);
|
|
|
|
if (!pform->proisagg)
|
|
{
|
|
ReleaseSysCache(ftup);
|
|
if (noError)
|
|
return InvalidOid;
|
|
/* we do not use the (*) notation for functions... */
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("function %s(%s) is not an aggregate",
|
|
NameListToString(aggname), format_type_be(basetype))));
|
|
}
|
|
|
|
ReleaseSysCache(ftup);
|
|
|
|
return oid;
|
|
}
|
|
|
|
/*
|
|
* LookupFuncName
|
|
* Given a possibly-qualified function name and a set of argument types,
|
|
* look up the function.
|
|
*
|
|
* If the function name is not schema-qualified, it is sought in the current
|
|
* namespace search path.
|
|
*
|
|
* If the function is not found, we return InvalidOid if noError is true,
|
|
* else raise an error.
|
|
*/
|
|
Oid
|
|
LookupFuncName(List *funcname, int nargs, const Oid *argtypes, bool noError)
|
|
{
|
|
FuncCandidateList clist;
|
|
|
|
clist = FuncnameGetCandidates(funcname, nargs);
|
|
|
|
while (clist)
|
|
{
|
|
if (memcmp(argtypes, clist->args, nargs * sizeof(Oid)) == 0)
|
|
return clist->oid;
|
|
clist = clist->next;
|
|
}
|
|
|
|
if (!noError)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_FUNCTION),
|
|
errmsg("function %s does not exist",
|
|
func_signature_string(funcname, nargs, argtypes))));
|
|
|
|
return InvalidOid;
|
|
}
|
|
|
|
/*
|
|
* LookupFuncNameTypeNames
|
|
* Like LookupFuncName, but the argument types are specified by a
|
|
* list of TypeName nodes.
|
|
*/
|
|
Oid
|
|
LookupFuncNameTypeNames(List *funcname, List *argtypes, bool noError)
|
|
{
|
|
Oid argoids[FUNC_MAX_ARGS];
|
|
int argcount;
|
|
int i;
|
|
|
|
MemSet(argoids, 0, FUNC_MAX_ARGS * sizeof(Oid));
|
|
argcount = length(argtypes);
|
|
if (argcount > FUNC_MAX_ARGS)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
|
|
errmsg("functions cannot have more than %d arguments",
|
|
FUNC_MAX_ARGS)));
|
|
|
|
for (i = 0; i < argcount; i++)
|
|
{
|
|
TypeName *t = (TypeName *) lfirst(argtypes);
|
|
|
|
argoids[i] = LookupTypeName(t);
|
|
|
|
if (!OidIsValid(argoids[i]))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_OBJECT),
|
|
errmsg("type \"%s\" does not exist",
|
|
TypeNameToString(t))));
|
|
|
|
argtypes = lnext(argtypes);
|
|
}
|
|
|
|
return LookupFuncName(funcname, argcount, argoids, noError);
|
|
}
|