[Libguestfs] [PATCH nbdkit 5/6] ocaml: Always unregister the global root and free the handle

If the OCaml code did not provide a close method, we would never call close_wrapper, and then we ended up leaking the global root and handle. --- plugins/ocaml/plugin.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/plugins/ocaml/plugin.c b/plugins/ocaml/plugin.c index fe781f9af..a4671d6ed 100644 --- a/plugins/ocaml/plugin.c +++ b/plugins/ocaml/plugin.c @@ -76,6 +76,7 @@ constructor (void) * nbdkit_plugin struct and return it from our own plugin_init * function. */ +static void close_wrapper (void *h); static void unload_wrapper (void); static void free_strings (void); static void remove_roots (void); @@ -92,6 +93,10 @@ static struct nbdkit_plugin plugin = { */ .name = NULL, + /* We always call these, even if the OCaml code does not provide a + * callback. + */ + .close = close_wrapper, .unload = unload_wrapper, }; @@ -345,6 +350,9 @@ open_wrapper (int readonly) CAMLreturnT (void *, ret); } +/* We always have a close function, since we need to unregister the + * global root and free the handle. + */ static void close_wrapper (void *h) { @@ -352,10 +360,12 @@ close_wrapper (void *h) CAMLparam0 (); CAMLlocal1 (rv); - rv = caml_callback_exn (close_fn, *(value *) h); - if (Is_exception_result (rv)) { - nbdkit_error ("%s", caml_format_exception (Extract_exception (rv))); - /*FALLTHROUGH*/ + if (close_fn) { + rv = caml_callback_exn (close_fn, *(value *) h); + if (Is_exception_result (rv)) { + nbdkit_error ("%s", caml_format_exception (Extract_exception (rv))); + /*FALLTHROUGH*/ + } } caml_remove_generational_global_root (h); -- 2.41.0