int object_as_write_buffer(PyObject *obj, void ** buffer, Py_ssize_t * buffer_len) {
Py_buffer *wpybuf;
if (PyMemoryView_Check(obj)) {
wpybuf = PyMemoryView_GET_BUFFER(obj);
if (wpybuf->buf==NULL)
return 1;
buffer[0] = wpybuf->buf;
return 0;
}
return PyObject_AsWriteBuffer(obj, buffer, buffer_len);
}
int object_as_buffer(PyObject *obj, const void ** buffer, Py_ssize_t * buffer_len) {
Py_buffer *rpybuf;
if (PyMemoryView_Check(obj)) {
rpybuf = PyMemoryView_GET_BUFFER(obj);
if (rpybuf->buf==NULL)
return 1;
buffer[0] = rpybuf->buf;
return 0;
}
return PyObject_AsReadBuffer(obj, buffer, buffer_len);
}
inline bool
setViaBuffer(jarray array, int start, uint length, PyObject* sequence, setFnc setter) {
//creates a PyMemoryView from sequence check for typeError,
// if no underlying py_buff exists.
if(! PyObject_CheckBuffer(sequence)) {
return false;
}
// ensure memory is contiguous and 'C' ordered, this may involve a copy.
PyObject* memview = PyMemoryView_GetContiguous(sequence, PyBUF_READ, 'C');
// this function is defined in jpype_memory_view, but unusable?!
// PyObject* memview = PyMemoryView_FromObject(sequence);
// check for TypeError, if no underlying py_buff exists.
PyObject* err = PyErr_Occurred();
if (err) {
PyErr_Clear();
return false;
}
// create a memory view
Py_buffer* py_buff = PyMemoryView_GET_BUFFER(memview);
// ensure length of buffer contains enough elements somehow.
if ((py_buff->len / sizeof(jelementtype)) != length) {
std::stringstream ss;
ss << "Underlying buffer does not contain requested number of elements! Has "
<< py_buff->len << ", but " << length <<" are requested. Element size is "
<< sizeof(jelementtype);
RAISE(JPypeException, ss.str());
}
jarraytype a = (jarraytype)array;
jelementtype* buffer = (jelementtype*) py_buff->buf;
JPJavaEnv* env = JPEnv::getJava();
try {
(env->*setter)(a, start, length, buffer);
} RETHROW_CATCH( /*cleanup*/ Py_DECREF(py_buff); Py_DECREF(memview); );
