/* ----------------------------------------------------------------
* FunctionNext
*
* This is a workhorse for ExecFunctionScan
* ----------------------------------------------------------------
*/
static TupleTableSlot *
FunctionNext(FunctionScanState *node)
{
TupleTableSlot *slot;
EState *estate;
ScanDirection direction;
Tuplestorestate *tuplestorestate;
bool should_free;
HeapTuple heapTuple;
/*
* get information from the estate and scan state
*/
estate = node->ss.ps.state;
direction = estate->es_direction;
tuplestorestate = node->tuplestorestate;
/*
* If first time through, read all tuples from function and put them in a
* tuplestore. Subsequent calls just fetch tuples from tuplestore.
*/
if (tuplestorestate == NULL)
{
ExprContext *econtext = node->ss.ps.ps_ExprContext;
TupleDesc funcTupdesc;
node->tuplestorestate = tuplestorestate =
ExecMakeTableFunctionResult(node->funcexpr,
econtext,
node->tupdesc,
&funcTupdesc);
/*
* If function provided a tupdesc, cross-check it. We only really
* need to do this for functions returning RECORD, but might as well
* do it always.
*/
if (funcTupdesc)
tupledesc_match(node->tupdesc, funcTupdesc);
}
/*
* Get the next tuple from tuplestore. Return NULL if no more tuples.
*/
heapTuple = tuplestore_getheaptuple(tuplestorestate,
ScanDirectionIsForward(direction),
&should_free);
slot = node->ss.ss_ScanTupleSlot;
if (heapTuple)
return ExecStoreTuple(heapTuple, slot, InvalidBuffer, should_free);
else
return ExecClearTuple(slot);
}
/* ----------------------------------------------------------------
* FunctionNext
*
* This is a workhorse for ExecFunctionScan
* ----------------------------------------------------------------
*/
static TupleTableSlot *
FunctionNext(FunctionScanState *node)
{
TupleTableSlot *slot;
EState *estate;
ScanDirection direction;
Tuplestorestate *tuplestorestate;
bool should_free;
HeapTuple heapTuple;
/*
* get information from the estate and scan state
*/
estate = node->ss.ps.state;
direction = estate->es_direction;
tuplestorestate = node->tuplestorestate;
/*
* If first time through, read all tuples from function and put them
* in a tuplestore. Subsequent calls just fetch tuples from
* tuplestore.
*/
if (tuplestorestate == NULL)
{
ExprContext *econtext = node->ss.ps.ps_ExprContext;
TupleDesc funcTupdesc;
node->tuplestorestate = tuplestorestate =
ExecMakeTableFunctionResult(node->funcexpr,
econtext,
node->tupdesc,
&funcTupdesc);
/*
* If function provided a tupdesc, cross-check it. We only really
* need to do this for functions returning RECORD, but might as
* well do it always.
*/
if (funcTupdesc && !tupledesc_match(node->tupdesc, funcTupdesc))
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("query-specified return row and actual function return row do not match")));
}
/*
* Get the next tuple from tuplestore. Return NULL if no more tuples.
*/
heapTuple = tuplestore_getheaptuple(tuplestorestate,
ScanDirectionIsForward(direction),
&should_free);
slot = node->ss.ss_ScanTupleSlot;
return ExecStoreTuple(heapTuple, slot, InvalidBuffer, should_free);
}
TupleCheckStatus
FilterInit(Filter *filter, TupleDesc desc, Oid collation)
{
int i;
ParsedFunction func;
HeapTuple ftup;
HeapTuple ltup;
Form_pg_proc pp;
Form_pg_language lp;
TupleCheckStatus status = NEED_COERCION_CHECK;
if (filter->funcstr == NULL)
return NO_COERCION;
/* parse filter function */
func = ParseFunction(filter->funcstr, true);
filter->funcid = func.oid;
filter->nargs = func.nargs;
for (i = 0; i < filter->nargs; i++)
{
/* Check for polymorphic types and internal pseudo-type argument */
if (IsPolymorphicType(func.argtypes[i]) ||
func.argtypes[i] == INTERNALOID)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("filter function does not support a polymorphic function and having a internal pseudo-type argument function: %s",
get_func_name(filter->funcid))));
filter->argtypes[i] = func.argtypes[i];
}
ftup = SearchSysCache(PROCOID, ObjectIdGetDatum(filter->funcid), 0, 0, 0);
pp = (Form_pg_proc) GETSTRUCT(ftup);
if (pp->proretset)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("filter function must not return set")));
/* Check data type of the function result value */
if (pp->prorettype == desc->tdtypeid && pp->prorettype != RECORDOID)
status = NO_COERCION;
else if (pp->prorettype == RECORDOID)
{
TupleDesc resultDesc = NULL;
/* Check for OUT parameters defining a RECORD result */
resultDesc = build_function_result_tupdesc_t(ftup);
if (resultDesc)
{
if (tupledesc_match(desc, resultDesc))
status = NO_COERCION;
FreeTupleDesc(resultDesc);
}
}
else if (get_typtype(pp->prorettype) != TYPTYPE_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("function return data type and target table data type do not match")));
/* Get default values */
#if PG_VERSION_NUM >= 80400
filter->fn_ndargs = pp->pronargdefaults;
if (filter->fn_ndargs > 0)
{
Datum proargdefaults;
bool isnull;
char *str;
List *defaults;
ListCell *l;
filter->defaultValues = palloc(sizeof(Datum) * filter->fn_ndargs);
filter->defaultIsnull = palloc(sizeof(bool) * filter->fn_ndargs);
proargdefaults = SysCacheGetAttr(PROCOID, ftup,
Anum_pg_proc_proargdefaults,
&isnull);
Assert(!isnull);
str = TextDatumGetCString(proargdefaults);
defaults = (List *) stringToNode(str);
Assert(IsA(defaults, List));
pfree(str);
filter->econtext = CreateStandaloneExprContext();
i = 0;
foreach(l, defaults)
{
Expr *expr = (Expr *) lfirst(l);
ExprState *argstate;
ExprDoneCond thisArgIsDone;
argstate = ExecInitExpr(expr, NULL);
filter->defaultValues[i] = ExecEvalExpr(argstate,
filter->econtext,
&filter->defaultIsnull[i],
&thisArgIsDone);
if (thisArgIsDone != ExprSingleResult)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("functions and operators can take at most one set argument")));
i++;
}
static void
FunctionParserInit(FunctionParser *self, Checker *checker, const char *infile, TupleDesc desc, bool multi_process, Oid collation)
{
int i;
ParsedFunction function;
int nargs;
Oid funcid;
HeapTuple ftup;
Form_pg_proc pp;
bool tupledesc_matched = false;
if (pg_strcasecmp(infile, "stdin") == 0)
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot load from STDIN in the case of \"TYPE = FUNCTION\"")));
if (checker->encoding != -1)
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("does not support parameter \"ENCODING\" in \"TYPE = FUNCTION\"")));
function = ParseFunction(infile, false);
funcid = function.oid;
fmgr_info(funcid, &self->flinfo);
if (!self->flinfo.fn_retset)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function must return set")));
ftup = SearchSysCache(PROCOID, ObjectIdGetDatum(funcid), 0, 0, 0);
pp = (Form_pg_proc) GETSTRUCT(ftup);
/* Check data type of the function result value */
if (pp->prorettype == desc->tdtypeid && desc->tdtypeid != RECORDOID)
tupledesc_matched = true;
else if (pp->prorettype == RECORDOID)
{
TupleDesc resultDesc = NULL;
/* Check for OUT parameters defining a RECORD result */
resultDesc = build_function_result_tupdesc_t(ftup);
if (resultDesc)
{
tupledesc_match(desc, resultDesc);
tupledesc_matched = true;
FreeTupleDesc(resultDesc);
}
}
else if (get_typtype(pp->prorettype) != TYPTYPE_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("function return data type and target table data type do not match")));
if (tupledesc_matched && checker->tchecker)
checker->tchecker->status = NO_COERCION;
/*
* assign arguments
*/
nargs = function.nargs;
for (i = 0;
#if PG_VERSION_NUM >= 80400
i < nargs - function.nvargs;
#else
i < nargs;
#endif
++i)
{
if (function.args[i] == NULL)
{
if (self->flinfo.fn_strict)
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("function is strict, but argument %d is NULL", i)));
self->fcinfo.argnull[i] = true;
}
else
{
Oid typinput;
Oid typioparam;
getTypeInputInfo(pp->proargtypes.values[i], &typinput, &typioparam);
self->fcinfo.arg[i] = OidInputFunctionCall(typinput,
(char *) function.args[i], typioparam, -1);
self->fcinfo.argnull[i] = false;
pfree(function.args[i]);
}
}
/*
* assign variadic arguments
*/
#if PG_VERSION_NUM >= 80400
if (function.nvargs > 0)
{
int nfixedarg;
Oid func;
Oid element_type;
int16 elmlen;
bool elmbyval;
char elmalign;
char elmdelim;
Oid elmioparam;
Datum *elems;
bool *nulls;
int dims[1];
int lbs[1];
ArrayType *arry;
nfixedarg = i;
element_type = pp->provariadic;
/*
* Get info about element type, including its input conversion proc
*/
get_type_io_data(element_type, IOFunc_input,
&elmlen, &elmbyval, &elmalign, &elmdelim,
&elmioparam, &func);
elems = (Datum *) palloc(function.nvargs * sizeof(Datum));
nulls = (bool *) palloc0(function.nvargs * sizeof(bool));
for (i = 0; i < function.nvargs; i++)
{
if (function.args[nfixedarg + i] == NULL)
nulls[i] = true;
else
{
elems[i] = OidInputFunctionCall(func,
(char *) function.args[nfixedarg + i], elmioparam, -1);
pfree(function.args[nfixedarg + i]);
}
}
dims[0] = function.nvargs;
lbs[0] = 1;
arry = construct_md_array(elems, nulls, 1, dims, lbs, element_type,
elmlen, elmbyval, elmalign);
self->fcinfo.arg[nfixedarg] = PointerGetDatum(arry);
}
/*
* assign default arguments
*/
if (function.ndargs > 0)
{
Datum proargdefaults;
bool isnull;
char *str;
List *defaults;
int ndelete;
ListCell *l;
/* shouldn't happen, FuncnameGetCandidates messed up */
if (function.ndargs > pp->pronargdefaults)
elog(ERROR, "not enough default arguments");
proargdefaults = SysCacheGetAttr(PROCOID, ftup,
Anum_pg_proc_proargdefaults,
&isnull);
Assert(!isnull);
str = TextDatumGetCString(proargdefaults);
defaults = (List *) stringToNode(str);
Assert(IsA(defaults, List));
pfree(str);
/* Delete any unused defaults from the returned list */
ndelete = list_length(defaults) - function.ndargs;
while (ndelete-- > 0)
defaults = list_delete_first(defaults);
self->arg_econtext = CreateStandaloneExprContext();
foreach(l, defaults)
{
Expr *expr = (Expr *) lfirst(l);
ExprState *argstate;
ExprDoneCond thisArgIsDone;
/* probably shouldn't happen ... */
if (nargs >= FUNC_MAX_ARGS)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
errmsg("cannot pass more than %d arguments to a function", FUNC_MAX_ARGS)));
argstate = ExecInitExpr(expr, NULL);
self->fcinfo.arg[nargs] = ExecEvalExpr(argstate,
self->arg_econtext,
&self->fcinfo.argnull[nargs],
&thisArgIsDone);
if (thisArgIsDone != ExprSingleResult)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("functions and operators can take at most one set argument")));
nargs++;
}
/*
* ExecMakeTableFunctionResult
*
* Evaluate a table function, producing a materialized result in a Tuplestore
* object.
*
* This is used by nodeFunctionscan.c.
*/
Tuplestorestate *
ExecMakeTableFunctionResult(SetExprState *setexpr,
ExprContext *econtext,
MemoryContext argContext,
TupleDesc expectedDesc,
bool randomAccess)
{
Tuplestorestate *tupstore = NULL;
TupleDesc tupdesc = NULL;
Oid funcrettype;
bool returnsTuple;
bool returnsSet = false;
FunctionCallInfoData fcinfo;
PgStat_FunctionCallUsage fcusage;
ReturnSetInfo rsinfo;
HeapTupleData tmptup;
MemoryContext callerContext;
MemoryContext oldcontext;
bool first_time = true;
callerContext = CurrentMemoryContext;
funcrettype = exprType((Node *) setexpr->expr);
returnsTuple = type_is_rowtype(funcrettype);
/*
* Prepare a resultinfo node for communication. We always do this even if
* not expecting a set result, so that we can pass expectedDesc. In the
* generic-expression case, the expression doesn't actually get to see the
* resultinfo, but set it up anyway because we use some of the fields as
* our own state variables.
*/
rsinfo.type = T_ReturnSetInfo;
rsinfo.econtext = econtext;
rsinfo.expectedDesc = expectedDesc;
rsinfo.allowedModes = (int) (SFRM_ValuePerCall | SFRM_Materialize | SFRM_Materialize_Preferred);
if (randomAccess)
rsinfo.allowedModes |= (int) SFRM_Materialize_Random;
rsinfo.returnMode = SFRM_ValuePerCall;
/* isDone is filled below */
rsinfo.setResult = NULL;
rsinfo.setDesc = NULL;
/*
* Normally the passed expression tree will be a SetExprState, since the
* grammar only allows a function call at the top level of a table
* function reference. However, if the function doesn't return set then
* the planner might have replaced the function call via constant-folding
* or inlining. So if we see any other kind of expression node, execute
* it via the general ExecEvalExpr() code; the only difference is that we
* don't get a chance to pass a special ReturnSetInfo to any functions
* buried in the expression.
*/
if (!setexpr->elidedFuncState)
{
/*
* This path is similar to ExecMakeFunctionResultSet.
*/
returnsSet = setexpr->funcReturnsSet;
InitFunctionCallInfoData(fcinfo, &(setexpr->func),
list_length(setexpr->args),
setexpr->fcinfo_data.fncollation,
NULL, (Node *) &rsinfo);
/*
* Evaluate the function's argument list.
*
* We can't do this in the per-tuple context: the argument values
* would disappear when we reset that context in the inner loop. And
* the caller's CurrentMemoryContext is typically a query-lifespan
* context, so we don't want to leak memory there. We require the
* caller to pass a separate memory context that can be used for this,
* and can be reset each time through to avoid bloat.
*/
MemoryContextReset(argContext);
oldcontext = MemoryContextSwitchTo(argContext);
ExecEvalFuncArgs(&fcinfo, setexpr->args, econtext);
MemoryContextSwitchTo(oldcontext);
/*
* If function is strict, and there are any NULL arguments, skip
* calling the function and act like it returned NULL (or an empty
* set, in the returns-set case).
*/
if (setexpr->func.fn_strict)
{
int i;
for (i = 0; i < fcinfo.nargs; i++)
{
if (fcinfo.argnull[i])
goto no_function_result;
}
}
}
else
{
/* Treat setexpr as a generic expression */
InitFunctionCallInfoData(fcinfo, NULL, 0, InvalidOid, NULL, NULL);
}
/*
* Switch to short-lived context for calling the function or expression.
*/
MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
/*
* Loop to handle the ValuePerCall protocol (which is also the same
* behavior needed in the generic ExecEvalExpr path).
*/
for (;;)
{
Datum result;
CHECK_FOR_INTERRUPTS();
/*
* reset per-tuple memory context before each call of the function or
* expression. This cleans up any local memory the function may leak
* when called.
*/
ResetExprContext(econtext);
/* Call the function or expression one time */
if (!setexpr->elidedFuncState)
{
pgstat_init_function_usage(&fcinfo, &fcusage);
fcinfo.isnull = false;
rsinfo.isDone = ExprSingleResult;
result = FunctionCallInvoke(&fcinfo);
pgstat_end_function_usage(&fcusage,
rsinfo.isDone != ExprMultipleResult);
}
else
{
result =
ExecEvalExpr(setexpr->elidedFuncState, econtext, &fcinfo.isnull);
rsinfo.isDone = ExprSingleResult;
}
/* Which protocol does function want to use? */
if (rsinfo.returnMode == SFRM_ValuePerCall)
{
/*
* Check for end of result set.
*/
if (rsinfo.isDone == ExprEndResult)
break;
/*
* If first time through, build tuplestore for result. For a
* scalar function result type, also make a suitable tupdesc.
*/
if (first_time)
{
oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_query_memory);
tupstore = tuplestore_begin_heap(randomAccess, false, work_mem);
rsinfo.setResult = tupstore;
if (!returnsTuple)
{
tupdesc = CreateTemplateTupleDesc(1, false);
TupleDescInitEntry(tupdesc,
(AttrNumber) 1,
"column",
funcrettype,
-1,
0);
rsinfo.setDesc = tupdesc;
}
MemoryContextSwitchTo(oldcontext);
}
/*
* Store current resultset item.
*/
if (returnsTuple)
{
if (!fcinfo.isnull)
{
HeapTupleHeader td = DatumGetHeapTupleHeader(result);
if (tupdesc == NULL)
{
/*
* This is the first non-NULL result from the
* function. Use the type info embedded in the
* rowtype Datum to look up the needed tupdesc. Make
* a copy for the query.
*/
oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_query_memory);
tupdesc = lookup_rowtype_tupdesc_copy(HeapTupleHeaderGetTypeId(td),
HeapTupleHeaderGetTypMod(td));
rsinfo.setDesc = tupdesc;
MemoryContextSwitchTo(oldcontext);
}
else
{
/*
* Verify all later returned rows have same subtype;
* necessary in case the type is RECORD.
*/
if (HeapTupleHeaderGetTypeId(td) != tupdesc->tdtypeid ||
HeapTupleHeaderGetTypMod(td) != tupdesc->tdtypmod)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("rows returned by function are not all of the same row type")));
}
/*
* tuplestore_puttuple needs a HeapTuple not a bare
* HeapTupleHeader, but it doesn't need all the fields.
*/
tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
tmptup.t_data = td;
tuplestore_puttuple(tupstore, &tmptup);
}
else
{
/*
* NULL result from a tuple-returning function; expand it
* to a row of all nulls. We rely on the expectedDesc to
* form such rows. (Note: this would be problematic if
* tuplestore_putvalues saved the tdtypeid/tdtypmod from
* the provided descriptor, since that might not match
* what we get from the function itself. But it doesn't.)
*/
int natts = expectedDesc->natts;
bool *nullflags;
nullflags = (bool *) palloc(natts * sizeof(bool));
memset(nullflags, true, natts * sizeof(bool));
tuplestore_putvalues(tupstore, expectedDesc, NULL, nullflags);
}
}
else
{
/* Scalar-type case: just store the function result */
tuplestore_putvalues(tupstore, tupdesc, &result, &fcinfo.isnull);
}
/*
* Are we done?
*/
if (rsinfo.isDone != ExprMultipleResult)
break;
}
else if (rsinfo.returnMode == SFRM_Materialize)
{
/* check we're on the same page as the function author */
if (!first_time || rsinfo.isDone != ExprSingleResult)
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_SRF_PROTOCOL_VIOLATED),
errmsg("table-function protocol for materialize mode was not followed")));
/* Done evaluating the set result */
break;
}
else
ereport(ERROR,
(errcode(ERRCODE_E_R_I_E_SRF_PROTOCOL_VIOLATED),
errmsg("unrecognized table-function returnMode: %d",
(int) rsinfo.returnMode)));
first_time = false;
}
no_function_result:
/*
* If we got nothing from the function (ie, an empty-set or NULL result),
* we have to create the tuplestore to return, and if it's a
* non-set-returning function then insert a single all-nulls row. As
* above, we depend on the expectedDesc to manufacture the dummy row.
*/
if (rsinfo.setResult == NULL)
{
MemoryContextSwitchTo(econtext->ecxt_per_query_memory);
tupstore = tuplestore_begin_heap(randomAccess, false, work_mem);
rsinfo.setResult = tupstore;
if (!returnsSet)
{
int natts = expectedDesc->natts;
bool *nullflags;
MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
nullflags = (bool *) palloc(natts * sizeof(bool));
memset(nullflags, true, natts * sizeof(bool));
tuplestore_putvalues(tupstore, expectedDesc, NULL, nullflags);
}
}
/*
* If function provided a tupdesc, cross-check it. We only really need to
* do this for functions returning RECORD, but might as well do it always.
*/
if (rsinfo.setDesc)
{
tupledesc_match(expectedDesc, rsinfo.setDesc);
/*
* If it is a dynamically-allocated TupleDesc, free it: it is
* typically allocated in a per-query context, so we must avoid
* leaking it across multiple usages.
*/
if (rsinfo.setDesc->tdrefcount == -1)
FreeTupleDesc(rsinfo.setDesc);
}
MemoryContextSwitchTo(callerContext);
/* All done, pass back the tuplestore */
return rsinfo.setResult;
}
