/*
* Common subroutine for num_nulls() and num_nonnulls().
* Returns TRUE if successful, FALSE if function should return NULL.
* If successful, total argument count and number of nulls are
* returned into *nargs and *nulls.
*/
static bool
count_nulls(FunctionCallInfo fcinfo,
int32 *nargs, int32 *nulls)
{
int32 count = 0;
int i;
/* Did we get a VARIADIC array argument, or separate arguments? */
if (get_fn_expr_variadic(fcinfo->flinfo))
{
ArrayType *arr;
int ndims,
nitems,
*dims;
bits8 *bitmap;
Assert(PG_NARGS() == 1);
/*
* If we get a null as VARIADIC array argument, we can't say anything
* useful about the number of elements, so return NULL. This behavior
* is consistent with other variadic functions - see concat_internal.
*/
if (PG_ARGISNULL(0))
return false;
/*
* Non-null argument had better be an array. We assume that any call
* context that could let get_fn_expr_variadic return true will have
* checked that a VARIADIC-labeled parameter actually is an array. So
* it should be okay to just Assert that it's an array rather than
* doing a full-fledged error check.
*/
Assert(OidIsValid(get_base_element_type(get_fn_expr_argtype(fcinfo->flinfo, 0))));
/* OK, safe to fetch the array value */
arr = PG_GETARG_ARRAYTYPE_P(0);
/* Count the array elements */
ndims = ARR_NDIM(arr);
dims = ARR_DIMS(arr);
nitems = ArrayGetNItems(ndims, dims);
/* Count those that are NULL */
bitmap = ARR_NULLBITMAP(arr);
if (bitmap)
{
int bitmask = 1;
for (i = 0; i < nitems; i++)
{
if ((*bitmap & bitmask) == 0)
count++;
bitmask <<= 1;
if (bitmask == 0x100)
{
bitmap++;
bitmask = 1;
}
}
}
*nargs = nitems;
*nulls = count;
}
else
{
/* Separate arguments, so just count 'em */
for (i = 0; i < PG_NARGS(); i++)
{
if (PG_ARGISNULL(i))
count++;
}
*nargs = PG_NARGS();
*nulls = count;
}
return true;
}
/*
* extract_variadic_args
*
* Extract a set of argument values, types and NULL markers for a given
* input function which makes use of a VARIADIC input whose argument list
* depends on the caller context. When doing a VARIADIC call, the caller
* has provided one argument made of an array of values, so deconstruct the
* array data before using it for the next processing. If no VARIADIC call
* is used, just fill in the status data based on all the arguments given
* by the caller.
*
* This function returns the number of arguments generated, or -1 in the
* case of "VARIADIC NULL".
*/
int
extract_variadic_args(FunctionCallInfo fcinfo, int variadic_start,
bool convert_unknown, Datum **args, Oid **types,
bool **nulls)
{
bool variadic = get_fn_expr_variadic(fcinfo->flinfo);
Datum *args_res;
bool *nulls_res;
Oid *types_res;
int nargs,
i;
*args = NULL;
*types = NULL;
*nulls = NULL;
if (variadic)
{
ArrayType *array_in;
Oid element_type;
bool typbyval;
char typalign;
int16 typlen;
Assert(PG_NARGS() == variadic_start + 1);
if (PG_ARGISNULL(variadic_start))
return -1;
array_in = PG_GETARG_ARRAYTYPE_P(variadic_start);
element_type = ARR_ELEMTYPE(array_in);
get_typlenbyvalalign(element_type,
&typlen, &typbyval, &typalign);
deconstruct_array(array_in, element_type, typlen, typbyval,
typalign, &args_res, &nulls_res,
&nargs);
/* All the elements of the array have the same type */
types_res = (Oid *) palloc0(nargs * sizeof(Oid));
for (i = 0; i < nargs; i++)
types_res[i] = element_type;
}
else
{
nargs = PG_NARGS() - variadic_start;
Assert(nargs > 0);
nulls_res = (bool *) palloc0(nargs * sizeof(bool));
args_res = (Datum *) palloc0(nargs * sizeof(Datum));
types_res = (Oid *) palloc0(nargs * sizeof(Oid));
for (i = 0; i < nargs; i++)
{
nulls_res[i] = PG_ARGISNULL(i + variadic_start);
types_res[i] = get_fn_expr_argtype(fcinfo->flinfo,
i + variadic_start);
/*
* Turn a constant (more or less literal) value that's of unknown
* type into text if required. Unknowns come in as a cstring
* pointer. Note: for functions declared as taking type "any", the
* parser will not do any type conversion on unknown-type literals
* (that is, undecorated strings or NULLs).
*/
if (convert_unknown &&
types_res[i] == UNKNOWNOID &&
get_fn_expr_arg_stable(fcinfo->flinfo, i + variadic_start))
{
types_res[i] = TEXTOID;
if (PG_ARGISNULL(i + variadic_start))
args_res[i] = (Datum) 0;
else
args_res[i] =
CStringGetTextDatum(PG_GETARG_POINTER(i + variadic_start));
}
else
{
/* no conversion needed, just take the datum as given */
args_res[i] = PG_GETARG_DATUM(i + variadic_start);
}
if (!OidIsValid(types_res[i]) ||
(convert_unknown && types_res[i] == UNKNOWNOID))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not determine data type for argument %d",
i + 1)));
}
}
/* Fill in results */
*args = args_res;
*nulls = nulls_res;
*types = types_res;
return nargs;
}
