Python Extension Module With Variable Number Of Arguments

I am trying to figure out how in C extension modules to have a variable (and maybe) quite large number of arguments to a function. Reading about PyArg_ParseTuple it seems you have

Solution 1:

I had used something like this earlier. It could be a bad code as I am not an experienced C coder, but it worked for me. The idea is, *args is just a Python tuple, and you can do anything that you could do with a Python tuple. You can check http://docs.python.org/c-api/tuple.html .

intParseArguments(unsignedlong arr[],Py_ssize_t size, PyObject *args){
    /* Get arbitrary number of positive numbers from Py_Tuple */
    Py_ssize_t i;
    PyObject *temp_p, *temp_p2;


    for (i=0;i<size;i++) {
        temp_p = PyTuple_GetItem(args,i);
        if(temp_p == NULL) {returnNULL;}

        /* Check if temp_p is numeric */if (PyNumber_Check(temp_p) != 1) {
            PyErr_SetString(PyExc_TypeError,"Non-numeric argument.");
            returnNULL;
        }

        /* Convert number to python long and than C unsigned long */
        temp_p2 = PyNumber_Long(temp_p);
        arr[i] = PyLong_AsUnsignedLong(temp_p2);
        Py_DECREF(temp_p2);
        if (arr[i] == 0) {
            PyErr_SetString(PyExc_ValueError,"Zero doesn't allowed as argument.");
            returnNULL;
        }
        if (PyErr_Occurred()) {returnNULL; }
    }

    return1;
}

I was calling this function like this:

static PyObject *
function_name_was_here(PyObject *self, PyObject *args){
    Py_ssize_t TupleSize = PyTuple_Size(args);
    Py_ssize_t i;
    structbigcouples *temp = malloc(sizeof(struct bigcouples));
    unsignedlong current;

    if(!TupleSize) {
        if(!PyErr_Occurred()) 
            PyErr_SetString(PyExc_TypeError,"You must supply at least one argument.");
        free(temp);
        returnNULL;
    }

    unsignedlong *nums = malloc(TupleSize * sizeof(unsignedlong));

    if(!ParseArguments(nums, TupleSize, args)){
        /* Make a cleanup and than return null*/return null;
    }