bpo-30347: Stop crashes when concurrently iterate over itertools.groupby() iterators. (#1557)

This commit is contained in:
Serhiy Storchaka 2017-09-26 21:47:56 +03:00 committed by GitHub
parent 114454e9f6
commit c740e4fe8a
3 changed files with 56 additions and 36 deletions

View File

@ -2017,6 +2017,30 @@ class RegressionTests(unittest.TestCase):
with self.assertRaises(StopIteration):
next(it)
def test_issue30347_1(self):
def f(n):
if n == 5:
list(b)
return n != 6
for (k, b) in groupby(range(10), f):
list(b) # shouldn't crash
def test_issue30347_2(self):
class K:
def __init__(self, v):
pass
def __eq__(self, other):
nonlocal i
i += 1
if i == 1:
next(g, None)
return True
i = 0
g = next(groupby(range(10), K))[1]
for j in range(2):
next(g, None) # shouldn't crash
class SubclassWithKwargsTest(unittest.TestCase):
def test_keywords_in_subclass(self):
# count is not subclassable...

View File

@ -0,0 +1 @@
Stop crashes when concurrently iterate over itertools.groupby() iterators.

View File

@ -73,10 +73,37 @@ groupby_traverse(groupbyobject *gbo, visitproc visit, void *arg)
return 0;
}
Py_LOCAL_INLINE(int)
groupby_step(groupbyobject *gbo)
{
PyObject *newvalue, *newkey, *oldvalue;
newvalue = PyIter_Next(gbo->it);
if (newvalue == NULL)
return -1;
if (gbo->keyfunc == Py_None) {
newkey = newvalue;
Py_INCREF(newvalue);
} else {
newkey = PyObject_CallFunctionObjArgs(gbo->keyfunc, newvalue, NULL);
if (newkey == NULL) {
Py_DECREF(newvalue);
return -1;
}
}
oldvalue = gbo->currvalue;
gbo->currvalue = newvalue;
Py_XSETREF(gbo->currkey, newkey);
Py_XDECREF(oldvalue);
return 0;
}
static PyObject *
groupby_next(groupbyobject *gbo)
{
PyObject *newvalue, *newkey, *r, *grouper;
PyObject *r, *grouper;
gbo->currgrouper = NULL;
/* skip to next iteration group */
@ -95,25 +122,9 @@ groupby_next(groupbyobject *gbo)
break;
}
newvalue = PyIter_Next(gbo->it);
if (newvalue == NULL)
if (groupby_step(gbo) < 0)
return NULL;
if (gbo->keyfunc == Py_None) {
newkey = newvalue;
Py_INCREF(newvalue);
} else {
newkey = PyObject_CallFunctionObjArgs(gbo->keyfunc, newvalue, NULL);
if (newkey == NULL) {
Py_DECREF(newvalue);
return NULL;
}
}
Py_XSETREF(gbo->currkey, newkey);
Py_XSETREF(gbo->currvalue, newvalue);
}
Py_INCREF(gbo->currkey);
Py_XSETREF(gbo->tgtkey, gbo->currkey);
@ -285,30 +296,14 @@ static PyObject *
_grouper_next(_grouperobject *igo)
{
groupbyobject *gbo = (groupbyobject *)igo->parent;
PyObject *newvalue, *newkey, *r;
PyObject *r;
int rcmp;
if (gbo->currgrouper != igo)
return NULL;
if (gbo->currvalue == NULL) {
newvalue = PyIter_Next(gbo->it);
if (newvalue == NULL)
if (groupby_step(gbo) < 0)
return NULL;
if (gbo->keyfunc == Py_None) {
newkey = newvalue;
Py_INCREF(newvalue);
} else {
newkey = PyObject_CallFunctionObjArgs(gbo->keyfunc, newvalue, NULL);
if (newkey == NULL) {
Py_DECREF(newvalue);
return NULL;
}
}
assert(gbo->currkey == NULL);
gbo->currkey = newkey;
gbo->currvalue = newvalue;
}
assert(gbo->currkey != NULL);