Re: [Libguestfs] [nbdkit PATCH v2 08/24] ocaml: Implement .cache script callback
On Wed, May 15, 2019 at 10:57:58PM -0500, Eric Blake wrote:
+static int
+can_cache_wrapper (void *h)
+{
+ CAMLparam0 ();
+ CAMLlocal1 (rv);
+
+ caml_leave_blocking_section ();
+
+ rv = caml_callback_exn (can_cache_fn, *(value *) h);
+ if (Is_exception_result (rv)) {
+ nbdkit_error ("%s", caml_format_exception (Extract_exception (rv)));
+ caml_enter_blocking_section ();
+ CAMLreturnT (int, -1);
+ }
+
+ caml_enter_blocking_section ();
+ CAMLreturnT (int, Int_val (rv));
The not very obvious implicit assumption here is that the order of the
Cache* flags in the OCaml code is the same as the numbering of the
NBDKIT_CACHE_* flags in the C code, which it is, so we should be good.
Rich.
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