Function hmac_sha256

python/stringzilla.c:1616–1718

    "  TypeError: If arguments are not string-like or incorrect number provided.";

static PyObject *hmac_sha256(PyObject *self, PyObject *const *args, Py_ssize_t positional_args_count,
                             PyObject *args_names_tuple) {
    sz_unused_(self);

    // Parse arguments
    PyObject *key_obj = NULL;
    PyObject *message_obj = NULL;

    // Get count of keyword arguments
    Py_ssize_t const args_names_count = args_names_tuple ? PyTuple_Size(args_names_tuple) : 0;
    Py_ssize_t const total_args = positional_args_count + args_names_count;

    // Validate total argument count
    if (total_args != 2) {
        PyErr_SetString(PyExc_TypeError, "hmac_sha256() expects exactly 2 arguments");
        return NULL;
    }

    // Handle positional arguments
    if (positional_args_count >= 1) key_obj = args[0];
    if (positional_args_count >= 2) message_obj = args[1];

    // Handle keyword arguments
    if (args_names_count > 0) {
        for (Py_ssize_t i = 0; i < args_names_count; ++i) {
            PyObject *const key = PyTuple_GetItem(args_names_tuple, i);
            PyObject *const value = args[positional_args_count + i];

            if (PyUnicode_CompareWithASCIIString(key, "key") == 0) {
                if (key_obj) {
                    PyErr_SetString(PyExc_TypeError, "key specified twice");
                    return NULL;
                }
                key_obj = value;
            }
            else if (PyUnicode_CompareWithASCIIString(key, "message") == 0) {
                if (message_obj) {
                    PyErr_SetString(PyExc_TypeError, "message specified twice");
                    return NULL;
                }
                message_obj = value;
            }
            else {
                PyErr_Format(PyExc_TypeError, "unexpected keyword argument: %S", key);
                return NULL;
            }
        }
    }

    // Validate all required arguments are provided
    if (!key_obj || !message_obj) {
        PyErr_SetString(PyExc_TypeError, "hmac_sha256() missing required arguments");
        return NULL;
    }

    sz_string_view_t key, message;
    if (!sz_py_export_string_like(key_obj, &key.start, &key.length)) {
        wrap_current_exception("Key must be string-like");