Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

bpo-34784: Fix PyStructSequence_NewType #9524

Closed
wants to merge 1 commit into from
Closed

bpo-34784: Fix PyStructSequence_NewType #9524

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
195 changes: 108 additions & 87 deletions Objects/structseq.c
View file
Open in desktop
Expand Up @@ -287,78 +287,48 @@ static PyMethodDef structseq_methods[] = {
{NULL, NULL}
};

static PyTypeObject _struct_sequence_template = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
NULL, /* tp_name */
sizeof(PyStructSequence) - sizeof(PyObject *), /* tp_basicsize */
sizeof(PyObject *), /* tp_itemsize */
(destructor)structseq_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
(reprfunc)structseq_repr, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT, /* tp_flags */
NULL, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
structseq_methods, /* tp_methods */
NULL, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
0, /* tp_init */
0, /* tp_alloc */
structseq_new, /* tp_new */
};
static void count_members(PyStructSequence_Desc *desc, Py_ssize_t *n_members, Py_ssize_t *n_unnamed_members) {
Py_ssize_t i;

int
PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
{
PyObject *dict;
PyMemberDef* members;
Py_ssize_t n_members, n_unnamed_members, i, k;
*n_unnamed_members = 0;
for (i = 0; desc->fields[i].name != NULL; ++i)
if (desc->fields[i].name == PyStructSequence_UnnamedField)
(*n_unnamed_members)++;
(*n_members) = i;
}

static int initialize_structseq_dict(PyStructSequence_Desc *desc, PyObject* dict) {
PyObject *v;
Py_ssize_t n_members, n_unnamed_members;

#ifdef Py_TRACE_REFS
/* if the type object was chained, unchain it first
before overwriting its storage */
if (type->ob_base.ob_base._ob_next) {
_Py_ForgetReference((PyObject*)type);
}
#endif
#define SET_DICT_FROM_SIZE(key, value) \
do { \
v = PyLong_FromSsize_t(value); \
if (v == NULL) \
return -1; \
if (PyDict_SetItemString(dict, key, v) < 0) { \
Py_DECREF(v); \
return -1; \
} \
Py_DECREF(v); \
} while (0)

n_unnamed_members = 0;
for (i = 0; desc->fields[i].name != NULL; ++i)
if (desc->fields[i].name == PyStructSequence_UnnamedField)
n_unnamed_members++;
n_members = i;
count_members(desc, &n_members, &n_unnamed_members);
SET_DICT_FROM_SIZE(visible_length_key, desc->n_in_sequence);
SET_DICT_FROM_SIZE(real_length_key, n_members);
SET_DICT_FROM_SIZE(unnamed_fields_key, n_unnamed_members);
return 0;
}

memcpy(type, &_struct_sequence_template, sizeof(PyTypeObject));
type->tp_base = &PyTuple_Type;
type->tp_name = desc->name;
type->tp_doc = desc->doc;
static PyMemberDef* initialize_members(PyStructSequence_Desc *desc) {
PyMemberDef* members;
Py_ssize_t n_members, n_unnamed_members, i, k;

members = PyMem_NEW(PyMemberDef, n_members-n_unnamed_members+1);
count_members(desc, &n_members, &n_unnamed_members);
members = PyMem_NEW(PyMemberDef, n_members-n_unnamed_members + 1);
if (members == NULL) {
PyErr_NoMemory();
return -1;
return NULL;
}

for (i = k = 0; i < n_members; ++i) {
Expand All @@ -373,29 +343,45 @@ PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
k++;
}
members[k].name = NULL;
return members;
}

int
PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
{
PyMemberDef* members;

#ifdef Py_TRACE_REFS
/* if the type object was chained, unchain it first
before overwriting its storage */
if (type->ob_base.ob_base._ob_next) {
_Py_ForgetReference((PyObject*)type);
}
#endif

Py_REFCNT(type) = 1;
type->tp_name = desc->name;
type->tp_basicsize = sizeof(PyStructSequence) - sizeof(PyObject *);
type->tp_itemsize = sizeof(PyObject *);
type->tp_dealloc = (destructor)structseq_dealloc;
type->tp_repr = (reprfunc)structseq_repr;
type->tp_doc = desc->doc;
type->tp_base = &PyTuple_Type;
type->tp_methods = structseq_methods;
type->tp_new = structseq_new;
type->tp_flags = Py_TPFLAGS_DEFAULT;

members = initialize_members(desc);
if (members == NULL)
return -1;
type->tp_members = members;

if (PyType_Ready(type) < 0)
return -1;
Py_INCREF(type);

dict = type->tp_dict;
#define SET_DICT_FROM_SIZE(key, value) \
do { \
v = PyLong_FromSsize_t(value); \
if (v == NULL) \
return -1; \
if (PyDict_SetItemString(dict, key, v) < 0) { \
Py_DECREF(v); \
return -1; \
} \
Py_DECREF(v); \
} while (0)

SET_DICT_FROM_SIZE(visible_length_key, desc->n_in_sequence);
SET_DICT_FROM_SIZE(real_length_key, n_members);
SET_DICT_FROM_SIZE(unnamed_fields_key, n_unnamed_members);
if (initialize_structseq_dict(desc, type->tp_dict) < 0)
return -1;

return 0;
}
Expand All @@ -409,16 +395,51 @@ PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
PyTypeObject*
PyStructSequence_NewType(PyStructSequence_Desc *desc)
{
PyTypeObject *result;
PyObject* type;
PyObject* bases;
PyMemberDef* members;

PyType_Spec* spec = PyMem_NEW(PyType_Spec, 1);
spec->name = desc->name;
spec->basicsize = sizeof(PyStructSequence) - sizeof(PyObject *);
spec->itemsize = sizeof(PyObject *);
spec->flags = Py_TPFLAGS_DEFAULT;
spec->slots = PyMem_NEW(PyType_Slot, 6);

spec->slots[0].slot = Py_tp_dealloc;
spec->slots[0].pfunc = (destructor)structseq_dealloc;

spec->slots[1].slot = Py_tp_repr;
spec->slots[1].pfunc = (reprfunc)structseq_repr;

result = (PyTypeObject*)PyType_GenericAlloc(&PyType_Type, 0);
if (result == NULL)
spec->slots[2].slot = Py_tp_doc;
spec->slots[2].pfunc = (void*)desc->doc;

spec->slots[3].slot = Py_tp_methods;
spec->slots[3].pfunc = structseq_methods;

spec->slots[4].slot = Py_tp_new;
spec->slots[4].pfunc = structseq_new;

members = initialize_members(desc);
if (members == NULL)
return NULL;
if (PyStructSequence_InitType2(result, desc) < 0) {
Py_DECREF(result);
spec->slots[5].slot = Py_tp_members;
spec->slots[5].pfunc = members;

spec->slots[6].slot = 0;
spec->slots[6].pfunc = 0;

bases = PyTuple_Pack(1, &PyTuple_Type);
type = PyType_FromSpecWithBases(spec, bases);
if (type == NULL)
return NULL;
}
return result;
Py_INCREF(type);

if (initialize_structseq_dict(desc, ((PyTypeObject *)type)->tp_dict) < 0)
return NULL;

return type;
}

int _PyStructSequence_Init(void)
Expand Down