1 files changed, 9 insertions, 12 deletions

diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index cbe7425eae..6c88bbb2b0 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -305,7 +305,7 @@ _enter_buffered_busy(buffered *self)
             "could not acquire lock for %A at interpreter "
             "shutdown, possibly due to daemon threads",
             (PyObject *) self);
-        char *msg = PyUnicode_AsUTF8(msgobj);
+        const char *msg = PyUnicode_AsUTF8(msgobj);
         Py_FatalError(msg);
     }
     return 1;
@@ -454,7 +454,8 @@ buffered_dealloc_warn(buffered *self, PyObject *source)
 {
     if (self->ok && self->raw) {
         PyObject *r;
-        r = _PyObject_CallMethodId(self->raw, &PyId__dealloc_warn, "O", source);
+        r = _PyObject_CallMethodIdObjArgs(self->raw, &PyId__dealloc_warn,
+                                          source, NULL);
         if (r)
             Py_DECREF(r);
         else
@@ -904,7 +905,7 @@ _io__Buffered_read_impl(buffered *self, Py_ssize_t n)
     CHECK_INITIALIZED(self)
     if (n < -1) {
         PyErr_SetString(PyExc_ValueError,
-                        "read length must be positive or -1");
+                        "read length must be non-negative or -1");
         return NULL;
     }
 
@@ -932,22 +933,20 @@ _io__Buffered_read_impl(buffered *self, Py_ssize_t n)
 
 /*[clinic input]
 _io._Buffered.read1
-    size as n: Py_ssize_t
+    size as n: Py_ssize_t = -1
     /
 [clinic start generated code]*/
 
 static PyObject *
 _io__Buffered_read1_impl(buffered *self, Py_ssize_t n)
-/*[clinic end generated code: output=bcc4fb4e54d103a3 input=8d2869c18b983184]*/
+/*[clinic end generated code: output=bcc4fb4e54d103a3 input=7d22de9630b61774]*/
 {
     Py_ssize_t have, r;
     PyObject *res = NULL;
 
     CHECK_INITIALIZED(self)
     if (n < 0) {
-        PyErr_SetString(PyExc_ValueError,
-                        "read length must be positive");
-        return NULL;
+        n = self->buffer_size;
     }
 
     CHECK_CLOSED(self, "read of closed file")
@@ -1690,8 +1689,7 @@ _bufferedreader_read_generic(buffered *self, Py_ssize_t n)
                 return res;
             }
             Py_DECREF(res);
-            Py_INCREF(Py_None);
-            return Py_None;
+            Py_RETURN_NONE;
         }
         remaining -= r;
         written += r;
@@ -1715,8 +1713,7 @@ _bufferedreader_read_generic(buffered *self, Py_ssize_t n)
                 return res;
             }
             Py_DECREF(res);
-            Py_INCREF(Py_None);
-            return Py_None;
+            Py_RETURN_NONE;
         }
         if (remaining > r) {
             memcpy(out + written, self->buffer + self->pos, r);