[Libguestfs] [PATCH 3/3] ruby: Check Ruby callback exists before we call it (RHBZ#733297).

From: "Richard W.M. Jones" <rjones(a)redhat.com&gt; --- generator/generator_ruby.ml | 20 ++++++++++++++------ 1 files changed, 14 insertions(+), 6 deletions(-) diff --git a/generator/generator_ruby.ml b/generator/generator_ruby.ml index eee6b7e..38121b5 100644 --- a/generator/generator_ruby.ml +++ b/generator/generator_ruby.ml @@ -246,13 +246,21 @@ ruby_event_callback_wrapper_wrapper (VALUE argvv) VALUE fn, eventv, event_handlev, bufv, arrayv; fn = argv[0]; - eventv = argv[1]; - event_handlev = argv[2]; - bufv = argv[3]; - arrayv = argv[4]; - rb_funcall (fn, rb_intern (\"call\"), 4, - eventv, event_handlev, bufv, arrayv); + /* Check the Ruby callback still exists. For reasons which are not + * fully understood, even though we registered this as a global root, + * it is still possible for the callback to go away (fn value remains + * but its type changes from T_DATA to T_NONE). (RHBZ#733297) + */ + if (rb_type (fn) != T_NONE) { + eventv = argv[1]; + event_handlev = argv[2]; + bufv = argv[3]; + arrayv = argv[4]; + + rb_funcall (fn, rb_intern (\"call\"), 4, + eventv, event_handlev, bufv, arrayv); + } return Qnil; } -- 1.7.6