search for: 305158e

...llback (h->debug_callback.user_data, context, msg); + CALL_CALLBACK (h->debug_callback, context, msg); else fprintf (stderr, "libnbd: debug: %s: %s: %s\n", h->hname, context ? : "unknown", msg); diff --git a/lib/internal.h b/lib/internal.h index 305158e..dc3676a 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -273,6 +273,10 @@ struct command { uint32_t error; /* Local errno value */ }; +/* Call a callback. */ +#define CALL_CALLBACK(cb, ...) \ + (cb).callback ((cb).user_data, ##__VA_ARGS__) + /* Free a callback. * * Note this works...

...ck) - if (h->debug_callback.free) - /* ignore return value */ - h->debug_callback.free (h->debug_callback.user_data); - h->debug_callback.callback = NULL; + FREE_CALLBACK (h->debug_callback); return 0; } diff --git a/lib/internal.h b/lib/internal.h index 5996a4f..305158e 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -273,6 +273,20 @@ struct command { uint32_t error; /* Local errno value */ }; +/* Free a callback. + * + * Note this works for any type of callback because the basic layout + * of the struct is the same for all of them. Therefore casting cb...

Patches 1 & 2 are rather complex, but the end result is that we pass closures + user_data + free function in single struct parameters as I described previously in this email: https://www.redhat.com/archives/libguestfs/2019-August/msg00210.html Patch 3 adds a convenient FREE_CALLBACK macro which seems a worthwhile simplification if you buy into 1 & 2. Patch 4 adds another macro which is