Issue #6241: Better type checking for the arguments of io.StringIO.
diff --git a/Modules/_io/stringio.c b/Modules/_io/stringio.c
index d773723..bfb099c 100644
--- a/Modules/_io/stringio.c
+++ b/Modules/_io/stringio.c
@@ -550,22 +550,42 @@
{
char *kwlist[] = {"initial_value", "newline", NULL};
PyObject *value = NULL;
+ PyObject *newline_obj = NULL;
char *newline = "\n";
- if (!PyArg_ParseTupleAndKeywords(args, kwds, "|Oz:__init__", kwlist,
- &value, &newline))
+ if (!PyArg_ParseTupleAndKeywords(args, kwds, "|OO:__init__", kwlist,
+ &value, &newline_obj))
return -1;
+ /* Parse the newline argument. This used to be done with the 'z'
+ specifier, however this allowed any object with the buffer interface to
+ be converted. Thus we have to parse it manually since we only want to
+ allow unicode objects or None. */
+ if (newline_obj == Py_None) {
+ newline = NULL;
+ }
+ else if (newline_obj) {
+ if (!PyUnicode_Check(newline_obj)) {
+ PyErr_Format(PyExc_TypeError,
+ "newline must be str or None, not %.200s",
+ Py_TYPE(newline_obj)->tp_name);
+ return -1;
+ }
+ newline = _PyUnicode_AsString(newline_obj);
+ if (newline == NULL)
+ return -1;
+ }
+
if (newline && newline[0] != '\0'
&& !(newline[0] == '\n' && newline[1] == '\0')
&& !(newline[0] == '\r' && newline[1] == '\0')
&& !(newline[0] == '\r' && newline[1] == '\n' && newline[2] == '\0')) {
PyErr_Format(PyExc_ValueError,
- "illegal newline value: %s", newline);
+ "illegal newline value: %R", newline_obj);
return -1;
}
if (value && value != Py_None && !PyUnicode_Check(value)) {
- PyErr_Format(PyExc_ValueError,
+ PyErr_Format(PyExc_TypeError,
"initial_value must be str or None, not %.200s",
Py_TYPE(value)->tp_name);
return -1;
@@ -577,6 +597,9 @@
Py_CLEAR(self->writenl);
Py_CLEAR(self->decoder);
+ assert((newline != NULL && newline_obj != Py_None) ||
+ (newline == NULL && newline_obj == Py_None));
+
if (newline) {
self->readnl = PyUnicode_FromString(newline);
if (self->readnl == NULL)