python3: Fix crashes in snapshot()

This makes sure all PyObject structs are always initialized to NULL,
this will fix issues such as (issue #239).

Signed-off-by: Stéphane Graber <[email protected]>
Acked-by: Serge E. Hallyn <[email protected]>

Author: stgraber

lxc.c

@@ -173,7 +173,7 @@ static lxc_attach_options_t *lxc_attach_parse_options(PyObject *kwds)
     PyObject *stdout_obj = NULL;
     PyObject *stderr_obj = NULL;
     PyObject *initial_cwd_obj = NULL;
-    PyObject *dummy;
+    PyObject *dummy = NULL;
     bool parse_result;
 
     lxc_attach_options_t default_options = LXC_ATTACH_OPTIONS_DEFAULT;
@@ -733,7 +733,8 @@ Container_create(Container *self, PyObject *args, PyObject *kwds)
     char* template_name = NULL;
     int flags = 0;
     char** create_args = {NULL};
-    PyObject *retval = NULL, *vargs = NULL;
+    PyObject *retval = NULL;
+    PyObject *vargs = NULL;
     int i = 0;
     static char *kwlist[] = {"template", "flags", "args", NULL};
 
@@ -1225,7 +1226,7 @@ Container_snapshot(Container *self, PyObject *args, PyObject *kwds)
     int retval = 0;
     int ret = 0;
     char newname[20];
-    PyObject *py_comment_path;
+    PyObject *py_comment_path = NULL;
 
     if (! PyArg_ParseTupleAndKeywords(args, kwds, "|O&", kwlist,
                                       PyUnicode_FSConverter, &py_comment_path))