1 files changed, 47 insertions, 2 deletions

diff --git a/Modules/_io/_iomodule.c b/Modules/_io/_iomodule.c
index 4a7e758cda..be0464c4fa 100644
--- a/Modules/_io/_iomodule.c
+++ b/Modules/_io/_iomodule.c
@@ -126,8 +126,7 @@ PyDoc_STRVAR(open_doc,
 "'b'       binary mode\n"
 "'t'       text mode (default)\n"
 "'+'       open a disk file for updating (reading and writing)\n"
-"'U'       universal newline mode (for backwards compatibility; unneeded\n"
-"          for new code)\n"
+"'U'       universal newline mode (deprecated)\n"
 "========= ===============================================================\n"
 "\n"
 "The default mode is 'rt' (open for reading text). For binary random\n"
@@ -143,6 +142,10 @@ PyDoc_STRVAR(open_doc,
 "returned as strings, the bytes having been first decoded using a\n"
 "platform-dependent encoding or using the specified encoding if given.\n"
 "\n"
+"'U' mode is deprecated and will raise an exception in future versions\n"
+"of Python.  It has no effect in Python 3.  Use newline to control\n"
+"universal newlines mode.\n"
+"\n"
 "buffering is an optional integer used to set the buffering policy.\n"
 "Pass 0 to switch buffering off (only allowed in binary mode), 1 to select\n"
 "line buffering (only usable in text mode), and an integer > 1 to indicate\n"
@@ -310,6 +313,9 @@ io_open(PyObject *self, PyObject *args, PyObject *kwds)
                             "can't use U and writing mode at once");
             return NULL;
         }
+        if (PyErr_WarnEx(PyExc_DeprecationWarning,
+                         "'U' mode is deprecated", 1) < 0)
+            return NULL;
         reading = 1;
     }
 
@@ -533,6 +539,45 @@ _PyIO_ConvertSsize_t(PyObject *obj, void *result) {
 }
 
 
+_PyIO_State *
+_PyIO_get_module_state(void)
+{
+    PyObject *mod = PyState_FindModule(&_PyIO_Module);
+    _PyIO_State *state;
+    if (mod == NULL || (state = IO_MOD_STATE(mod)) == NULL) {
+        PyErr_SetString(PyExc_RuntimeError,
+                        "could not find io module state "
+                        "(interpreter shutdown?)");
+        return NULL;
+    }
+    return state;
+}
+
+PyObject *
+_PyIO_get_locale_module(_PyIO_State *state)
+{
+    PyObject *mod;
+    if (state->locale_module != NULL) {
+        assert(PyWeakref_CheckRef(state->locale_module));
+        mod = PyWeakref_GET_OBJECT(state->locale_module);
+        if (mod != Py_None) {
+            Py_INCREF(mod);
+            return mod;
+        }
+        Py_CLEAR(state->locale_module);
+    }
+    mod = PyImport_ImportModule("_bootlocale");
+    if (mod == NULL)
+        return NULL;
+    state->locale_module = PyWeakref_NewRef(mod, NULL);
+    if (state->locale_module == NULL) {
+        Py_DECREF(mod);
+        return NULL;
+    }
+    return mod;
+}
+
+
 static int
 iomodule_traverse(PyObject *mod, visitproc visit, void *arg) {
     _PyIO_State *state = IO_MOD_STATE(mod);