PostgreSQL:如何在我自己的C函数中创建一个数字范围？

#include <postgres.h>
#include <fmgr.h>
#include <utils/builtins.h>

PG_MODULE_MAGIC;

PG_FUNCTION_INFO_V1(create_number_range);

Datum create_number_range(PG_FUNCTION_ARGS);

Datum create_number_range(PG_FUNCTION_ARGS) {
    int32 start = PG_GETARG_INT32(0);
    int32 end = PG_GETARG_INT32(1);
    int32 i;
    int32 *result;
    ArrayType *arr;

    if (start > end)
        ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("Invalid range")));

    result = palloc(sizeof(int32) * (end - start + 1));
    for (i = start; i <= end; i++)
        result[i - start] = i;

    arr = construct_array((Datum *) result, end - start + 1, INT4OID, sizeof(int32), true, 'i');

    PG_RETURN_ARRAYTYPE_P(arr);
}

gcc -fpic -c my_functions.c
gcc -shared -o my_functions.so my_functions.o

CREATE FUNCTION create_number_range(int, int)
    RETURNS int[]
    AS '/path/to/my_functions.so', 'create_number_range'
    LANGUAGE C STRICT;

SELECT create_number_range(1, 5);