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Issue #4580: slicing of memoryviews when itemsize != 1 is wrong.

Browse source 
Also fix len() to return number of items rather than length in bytes.

I'm sorry it was not possible for me to work on this without reindenting
a bit some stuff around. The indentation in memoryobject.c is a mess,
I'll open a separate bug for it.
This commit is contained in:
Antoine Pitrou 2009-01-03 16:59:18 +00:00
parent 8bcddcabd7
commit c3b39245a7
8 changed files with 297 additions and 216 deletions
Download patch file Download diff file Expand all files Collapse all files

131
Objects/memoryobject.c
View file

@ -3,26 +3,31 @@
#include "Python.h"
static void
dup_buffer(Py_buffer *dest, Py_buffer *src)
{
*dest = *src;
if (src->shape == &(src->len))
dest->shape = &(dest->len);
if (src->strides == &(src->itemsize))
dest->strides = &(dest->itemsize);
}
/* XXX The buffer API should mandate that the shape array be non-NULL, but
it would complicate some code since the (de)allocation semantics of shape
are not specified. */
static Py_ssize_t
get_shape0(Py_buffer *buf)
{
if (buf->shape != NULL)
return buf->shape[0];
assert(buf->ndim == 1 && buf->itemsize > 0);
return buf->len / buf->itemsize;
if (buf->ndim == 0)
return 1;
PyErr_SetString(PyExc_TypeError,
"exported buffer does not have any shape information associated "
"to it");
return -1;
}
static void
dup_buffer(Py_buffer *dest, Py_buffer *src)
{
*dest = *src;
if (src->ndim == 1 && src->shape != NULL) {
dest->shape = &(dest->smalltable[0]);
dest->shape[0] = get_shape0(src);
}
if (src->ndim == 1 && src->strides != NULL) {
dest->strides = &(dest->smalltable[1]);
dest->strides[0] = src->strides[0];
}
}
static int
@ -449,8 +454,6 @@ memory_tolist(PyMemoryViewObject *mem, PyObject *noargs)
return res;
}
static PyMethodDef memory_methods[] = {
{"tobytes", (PyCFunction)memory_tobytes, METH_NOARGS, NULL},
{"tolist", (PyCFunction)memory_tolist, METH_NOARGS, NULL},
@ -474,19 +477,19 @@ memory_dealloc(PyMemoryViewObject *self)
PyObject_CopyData(PyTuple_GET_ITEM(self->base,0),
PyTuple_GET_ITEM(self->base,1));
/* The view member should have readonly == -1 in
this instance indicating that the memory can
be "locked" and was locked and will be unlocked
again after this call.
*/
PyBuffer_Release(&(self->view));
}
else {
PyBuffer_Release(&(self->view));
}
Py_CLEAR(self->base);
/* The view member should have readonly == -1 in
this instance indicating that the memory can
be "locked" and was locked and will be unlocked
again after this call.
*/
PyBuffer_Release(&(self->view));
}
PyObject_GC_Del(self);
else {
PyBuffer_Release(&(self->view));
}
Py_CLEAR(self->base);
}
PyObject_GC_Del(self);
}
static PyObject *
@ -512,16 +515,10 @@ memory_str(PyMemoryViewObject *self)
}
/* Sequence methods */
static Py_ssize_t
memory_length(PyMemoryViewObject *self)
{
Py_buffer view;
if (PyObject_GetBuffer((PyObject *)self, &view, PyBUF_FULL) < 0)
return -1;
PyBuffer_Release(&view);
return view.len;
return get_shape0(&self->view);
}
/*
@ -589,40 +586,38 @@ memory_subscript(PyMemoryViewObject *self, PyObject *key)
}
}
else if (PySlice_Check(key)) {
Py_ssize_t start, stop, step, slicelength;
Py_ssize_t start, stop, step, slicelength;
if (PySlice_GetIndicesEx((PySliceObject*)key, get_shape0(view),
&start, &stop, &step, &slicelength) < 0) {
return NULL;
}
&start, &stop, &step, &slicelength) < 0) {
return NULL;
}
if (step == 1 && view->ndim == 1) {
Py_buffer newview;
void *newbuf = (char *) view->buf
+ start * view->itemsize;
int newflags = view->readonly
? PyBUF_CONTIG_RO : PyBUF_CONTIG;
if (step == 1 && view->ndim == 1) {
Py_buffer newview;
void *newbuf = (char *) view->buf
+ start * view->itemsize;
int newflags = view->readonly
? PyBUF_CONTIG_RO : PyBUF_CONTIG;
/* XXX There should be an API to create a subbuffer */
if (view->obj != NULL) {
if (PyObject_GetBuffer(view->obj,
&newview, newflags) == -1)
return NULL;
}
else {
newview = *view;
}
newview.buf = newbuf;
newview.len = slicelength;
newview.format = view->format;
if (view->shape == &(view->len))
newview.shape = &(newview.len);
if (view->strides == &(view->itemsize))
newview.strides = &(newview.itemsize);
return PyMemoryView_FromBuffer(&newview);
}
PyErr_SetNone(PyExc_NotImplementedError);
return NULL;
/* XXX There should be an API to create a subbuffer */
if (view->obj != NULL) {
if (PyObject_GetBuffer(view->obj, &newview, newflags) == -1)
return NULL;
}
else {
newview = *view;
}
newview.buf = newbuf;
newview.len = slicelength * newview.itemsize;
newview.format = view->format;
newview.shape = &(newview.smalltable[0]);
newview.shape[0] = slicelength;
newview.strides = &(newview.itemsize);
return PyMemoryView_FromBuffer(&newview);
}
PyErr_SetNone(PyExc_NotImplementedError);
return NULL;
}
PyErr_Format(PyExc_TypeError,
"cannot index memory using \"%.200s\"",
@ -747,7 +742,7 @@ memory_richcompare(PyObject *v, PyObject *w, int op)
if (vv.itemsize != ww.itemsize || vv.len != ww.len)
goto _end;
equal = !memcmp(vv.buf, ww.buf, vv.len * vv.itemsize);
equal = !memcmp(vv.buf, ww.buf, vv.len);
_end:
PyBuffer_Release(&vv);

2
Objects/unicodeobject.c
View file

@ -1205,7 +1205,7 @@ PyObject *PyUnicode_Decode(const char *s,
/* Decode via the codec registry */
buffer = NULL;
if (PyBuffer_FillInfo(&info, NULL, (void *)s, size, 1, PyBUF_SIMPLE) < 0)
if (PyBuffer_FillInfo(&info, NULL, (void *)s, size, 1, PyBUF_FULL_RO) < 0)
goto onError;
buffer = PyMemoryView_FromBuffer(&info);
if (buffer == NULL)