Function makeArrayResultArr

src/backend/utils/adt/arrayfuncs.c:5586–5650

* makeArrayResultArr - produce N+1-D final result of accumArrayResultArr * * astate is working state (must not be NULL) * rcontext is where to construct result * release is true if okay to release working state */

 *	release is true if okay to release working state
 */
Datum
makeArrayResultArr(ArrayBuildStateArr *astate,
				   MemoryContext rcontext,
				   bool release)
{
	ArrayType  *result;
	MemoryContext oldcontext;

	/* Build the final array result in rcontext */
	oldcontext = MemoryContextSwitchTo(rcontext);

	if (astate->ndims == 0)
	{
		/* No inputs, return empty array */
		result = construct_empty_array(astate->element_type);
	}
	else
	{
		int			dataoffset,
					nbytes;

		/* Check for overflow of the array dimensions */
		(void) ArrayGetNItems(astate->ndims, astate->dims);
		ArrayCheckBounds(astate->ndims, astate->dims, astate->lbs);

		/* Compute required space */
		nbytes = astate->nbytes;
		if (astate->nullbitmap != NULL)
		{
			dataoffset = ARR_OVERHEAD_WITHNULLS(astate->ndims, astate->nitems);
			nbytes += dataoffset;
		}
		else
		{
			dataoffset = 0;
			nbytes += ARR_OVERHEAD_NONULLS(astate->ndims);
		}

		result = (ArrayType *) palloc0(nbytes);
		SET_VARSIZE(result, nbytes);
		result->ndim = astate->ndims;
		result->dataoffset = dataoffset;
		result->elemtype = astate->element_type;

		memcpy(ARR_DIMS(result), astate->dims, astate->ndims * sizeof(int));
		memcpy(ARR_LBOUND(result), astate->lbs, astate->ndims * sizeof(int));
		memcpy(ARR_DATA_PTR(result), astate->data, astate->nbytes);

		if (astate->nullbitmap != NULL)
			array_bitmap_copy(ARR_NULLBITMAP(result), 0,
							  astate->nullbitmap, 0,
							  astate->nitems);
	}

	MemoryContextSwitchTo(oldcontext);

	/* Clean up all the junk */
	if (release)