Function array_data_set

numpy/core/src/multiarray/getset.c:338–420

}

static int
array_data_set(PyArrayObject *self, PyObject *op, void *NPY_UNUSED(ignored))
{
    void *buf;
    Py_ssize_t buf_len;
    int writeable=1;
    Py_buffer view;

    /* 2016-19-02, 1.12 */
    int ret = DEPRECATE("Assigning the 'data' attribute is an "
                        "inherently unsafe operation and will "
                        "be removed in the future.");
    if (ret < 0) {
        return -1;
    }

    if (op == NULL) {
        PyErr_SetString(PyExc_AttributeError,
                "Cannot delete array data");
        return -1;
    }
    if (PyObject_GetBuffer(op, &view, PyBUF_WRITABLE|PyBUF_SIMPLE) < 0) {
        writeable = 0;
        PyErr_Clear();
        if (PyObject_GetBuffer(op, &view, PyBUF_SIMPLE) < 0) {
            return -1;
        }
    }
    buf = view.buf;
    buf_len = view.len;
    /*
     * In Python 3 both of the deprecated functions PyObject_AsWriteBuffer and
     * PyObject_AsReadBuffer that this code replaces release the buffer. It is
     * up to the object that supplies the buffer to guarantee that the buffer
     * sticks around after the release.
     */
    PyBuffer_Release(&view);

    if (!PyArray_ISONESEGMENT(self)) {
        PyErr_SetString(PyExc_AttributeError,
                "cannot set single-segment buffer for discontiguous array");
        return -1;
    }
    if (PyArray_NBYTES(self) > buf_len) {
        PyErr_SetString(PyExc_AttributeError, "not enough data for array");
        return -1;
    }
    if (PyArray_FLAGS(self) & NPY_ARRAY_OWNDATA) {
        PyArray_XDECREF(self);
        size_t nbytes = PyArray_NBYTES(self);
        if (nbytes == 0) {
            nbytes = 1;
        }
        PyObject *handler = PyArray_HANDLER(self);
        if (handler == NULL) {
            /* This can happen if someone arbitrarily sets NPY_ARRAY_OWNDATA */
            PyErr_SetString(PyExc_RuntimeError,
                            "no memory handler found but OWNDATA flag set");