[Libguestfs] [PATCH libnbd v2 1/3] python: Allow Python callbacks to auto-retire by returning an integer.

[Richard W.M. Jones]

See equivalent change for OCaml in
commit d881d160e1cd9c9964782300a7652ffb4e506c27.

If the Python callback doesn't return something which looks like an
integer, assume 0 instead of returning an error.
---
 generator/generator | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/generator/generator b/generator/generator
index 55c4dfc..e5d9aaa 100755
--- a/generator/generator
+++ b/generator/generator
@@ -4234,7 +4234,12 @@ let print_python_binding name { args; optargs; ret; may_set_error } =
        pr "    Py_DECREF (py_args);\n";
        pr "\n";
        pr "    if (py_ret != NULL) {\n";
-       pr "      Py_DECREF (py_ret); /* return value is discarded */\n";
+       pr "      if (PyLong_Check (py_ret))\n";
+       pr "        ret = PyLong_AsLong (py_ret);\n";
+       pr "      else\n";
+       pr "        /* If it's not a long, just assume it's 0. */\n";
+       pr "        ret = 0;\n";
+       pr "      Py_DECREF (py_ret);\n";
        pr "    }\n";
        pr "    else {\n";
        pr "      ret = -1;\n";
-- 
2.22.0