Make read() and certificate() return bytes instead of bytearray instances.

Modules/_ssl.c

@@ -977,7 +977,7 @@ PySSL_peercert(PySSLObject *self, PyObject *args)
 			return NULL;
 		}
                 /* this is actually an immutable bytes sequence */
-		retval = PyBytes_FromStringAndSize
+		retval = PyString_FromStringAndSize
                   ((const char *) bytes_buf, len);
 		OPENSSL_free(bytes_buf);
 		return retval;
@@ -1281,13 +1281,8 @@ static PyObject *PySSL_SSLread(PySSLObject *self, PyObject *args)
 			Py_DECREF(buf);
 			return NULL;
 		} else if (sockstate == SOCKET_HAS_BEEN_CLOSED) {
-			/* should contain a zero-length string */
-			if (!buf_passed) {
-				PyBytes_Resize(buf, 0);
-				return buf;
-			} else {
-				return PyInt_FromLong(0);
-			}
+			count = 0;
+			goto done;
 		}
 	}
 	do {
@@ -1312,12 +1307,8 @@ static PyObject *PySSL_SSLread(PySSLObject *self, PyObject *args)
 			   (SSL_get_shutdown(self->ssl) ==
 			    SSL_RECEIVED_SHUTDOWN))
 		{
-			if (!buf_passed) {
-				PyBytes_Resize(buf, 0);
-				return buf;
-			} else {
-				return PyInt_FromLong(0);
-			}
+			count = 0;
+			goto done;
 		} else {
 			sockstate = SOCKET_OPERATION_OK;
 		}
@@ -1338,11 +1329,12 @@ static PyObject *PySSL_SSLread(PySSLObject *self, PyObject *args)
 		}
 		return PySSL_SetError(self, count, __FILE__, __LINE__);
 	}
+  done:
 	if (!buf_passed) {
-		if (count != len) {
-			PyBytes_Resize(buf, count);
-		}
-		return buf;
+		PyObject *res = PyString_FromStringAndSize(
+			PyBytes_AS_STRING(buf), count);
+		Py_DECREF(buf);
+		return res;
 	} else {
 		return PyInt_FromLong(count);
 	}