int
PySlice_GetIndicesEx(PyObject *_r, Py_ssize_t length,
Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step,
Py_ssize_t *slicelength)
{
if (PySlice_Unpack(_r, start, stop, step) < 0)
return -1;
*slicelength = PySlice_AdjustIndices(length, start, stop, *step);
return 0;
}
static PyObject *
mmap_subscript(mmap_object *self, PyObject *item)
{
CHECK_VALID(NULL);
if (PyIndex_Check(item)) {
Py_ssize_t i = PyNumber_AsSsize_t(item, PyExc_IndexError);
if (i == -1 && PyErr_Occurred())
return NULL;
if (i < 0)
i += self->size;
if (i < 0 || i >= self->size) {
PyErr_SetString(PyExc_IndexError,
"mmap index out of range");
return NULL;
}
return PyLong_FromLong(Py_CHARMASK(self->data[i]));
}
else if (PySlice_Check(item)) {
Py_ssize_t start, stop, step, slicelen;
if (PySlice_Unpack(item, &start, &stop, &step) < 0) {
return NULL;
}
slicelen = PySlice_AdjustIndices(self->size, &start, &stop, step);
if (slicelen <= 0)
return PyBytes_FromStringAndSize("", 0);
else if (step == 1)
return PyBytes_FromStringAndSize(self->data + start,
slicelen);
else {
char *result_buf = (char *)PyMem_Malloc(slicelen);
Py_ssize_t cur, i;
PyObject *result;
if (result_buf == NULL)
return PyErr_NoMemory();
for (cur = start, i = 0; i < slicelen;
cur += step, i++) {
result_buf[i] = self->data[cur];
}
result = PyBytes_FromStringAndSize(result_buf,
slicelen);
PyMem_Free(result_buf);
return result;
}
}
else {
PyErr_SetString(PyExc_TypeError,
"mmap indices must be integers");
return NULL;
}
}
static int
mmap_ass_subscript(mmap_object *self, PyObject *item, PyObject *value)
{
CHECK_VALID(-1);
if (!is_writable(self))
return -1;
if (PyIndex_Check(item)) {
Py_ssize_t i = PyNumber_AsSsize_t(item, PyExc_IndexError);
Py_ssize_t v;
if (i == -1 && PyErr_Occurred())
return -1;
if (i < 0)
i += self->size;
if (i < 0 || i >= self->size) {
PyErr_SetString(PyExc_IndexError,
"mmap index out of range");
return -1;
}
if (value == NULL) {
PyErr_SetString(PyExc_TypeError,
"mmap doesn't support item deletion");
return -1;
}
if (!PyIndex_Check(value)) {
PyErr_SetString(PyExc_TypeError,
"mmap item value must be an int");
return -1;
}
v = PyNumber_AsSsize_t(value, PyExc_TypeError);
if (v == -1 && PyErr_Occurred())
return -1;
if (v < 0 || v > 255) {
PyErr_SetString(PyExc_ValueError,
"mmap item value must be "
"in range(0, 256)");
return -1;
}
self->data[i] = (char) v;
return 0;
}
else if (PySlice_Check(item)) {
Py_ssize_t start, stop, step, slicelen;
Py_buffer vbuf;
if (PySlice_Unpack(item, &start, &stop, &step) < 0) {
return -1;
}
slicelen = PySlice_AdjustIndices(self->size, &start, &stop, step);
if (value == NULL) {
PyErr_SetString(PyExc_TypeError,
"mmap object doesn't support slice deletion");
return -1;
}
if (PyObject_GetBuffer(value, &vbuf, PyBUF_SIMPLE) < 0)
return -1;
if (vbuf.len != slicelen) {
PyErr_SetString(PyExc_IndexError,
"mmap slice assignment is wrong size");
PyBuffer_Release(&vbuf);
return -1;
}
if (slicelen == 0) {
}
else if (step == 1) {
memcpy(self->data + start, vbuf.buf, slicelen);
}
else {
Py_ssize_t cur, i;
for (cur = start, i = 0;
i < slicelen;
cur += step, i++)
{
self->data[cur] = ((char *)vbuf.buf)[i];
}
}
PyBuffer_Release(&vbuf);
return 0;
}
else {
PyErr_SetString(PyExc_TypeError,
"mmap indices must be integer");
return -1;
}
}
