Issue #10956: Buffered I/O classes retry reading or writing after a signal
has arrived and the handler returned successfully.
diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 55c0a23..386a880 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -714,6 +714,39 @@
return 0;
}
+/* Return 1 if an EnvironmentError with errno == EINTR is set (and then
+ clears the error indicator), 0 otherwise.
+ Should only be called when PyErr_Occurred() is true.
+*/
+static int
+_trap_eintr(void)
+{
+ static PyObject *eintr_int = NULL;
+ PyObject *typ, *val, *tb;
+ PyEnvironmentErrorObject *env_err;
+
+ if (eintr_int == NULL) {
+ eintr_int = PyLong_FromLong(EINTR);
+ assert(eintr_int != NULL);
+ }
+ if (!PyErr_ExceptionMatches(PyExc_EnvironmentError))
+ return 0;
+ PyErr_Fetch(&typ, &val, &tb);
+ PyErr_NormalizeException(&typ, &val, &tb);
+ env_err = (PyEnvironmentErrorObject *) val;
+ assert(env_err != NULL);
+ if (env_err->myerrno != NULL &&
+ PyObject_RichCompareBool(env_err->myerrno, eintr_int, Py_EQ) > 0) {
+ Py_DECREF(typ);
+ Py_DECREF(val);
+ Py_XDECREF(tb);
+ return 1;
+ }
+ /* This silences any error set by PyObject_RichCompareBool() */
+ PyErr_Restore(typ, val, tb);
+ return 0;
+}
+
/*
* Shared methods and wrappers
*/
@@ -1269,7 +1302,14 @@
memobj = PyMemoryView_FromBuffer(&buf);
if (memobj == NULL)
return -1;
- res = PyObject_CallMethodObjArgs(self->raw, _PyIO_str_readinto, memobj, NULL);
+ /* NOTE: PyErr_SetFromErrno() calls PyErr_CheckSignals() when EINTR
+ occurs so we needn't do it ourselves.
+ We then retry reading, ignoring the signal if no handler has
+ raised (see issue #10956).
+ */
+ do {
+ res = PyObject_CallMethodObjArgs(self->raw, _PyIO_str_readinto, memobj, NULL);
+ } while (res == NULL && _trap_eintr());
Py_DECREF(memobj);
if (res == NULL)
return -1;
@@ -1678,7 +1718,14 @@
memobj = PyMemoryView_FromBuffer(&buf);
if (memobj == NULL)
return -1;
- res = PyObject_CallMethodObjArgs(self->raw, _PyIO_str_write, memobj, NULL);
+ /* NOTE: PyErr_SetFromErrno() calls PyErr_CheckSignals() when EINTR
+ occurs so we needn't do it ourselves.
+ We then retry writing, ignoring the signal if no handler has
+ raised (see issue #10956).
+ */
+ do {
+ res = PyObject_CallMethodObjArgs(self->raw, _PyIO_str_write, memobj, NULL);
+ } while (res == NULL && _trap_eintr());
Py_DECREF(memobj);
if (res == NULL)
return -1;