search for: nbd_add_close_callback

The API changes from: int nbd_add_close_callback (struct nbd_handle *h, nbd_close_callback cb, void *user_data); to: int nbd_add_close_callback (struct nbd_handle *h, void *user_data, nbd_close_callback cb); The second way...

On 7/16/19 10:39 AM, Eric Blake wrote: > On 7/16/19 10:04 AM, Richard W.M. Jones wrote: >> The API changes from: >> >> int nbd_add_close_callback (struct nbd_handle *h, >> nbd_close_callback cb, >> void *user_data); >> >> to: >> >> int nbd_add_close_callback (struct nbd_handle *h, >> void *user_data, >>...

We previously needed nbd_add_close_callback to do cleanup from language bindings. However now we have closure lifetimes this is no longer needed and can be removed. See also: https://www.redhat.com/archives/libguestfs/2019-July/msg00213.html --- generator/generator | 18 ------------------ lib/handle.c | 35 ------------------------...

On Tue, Jul 16, 2019 at 11:38:36AM -0500, Eric Blake wrote: > On 7/16/19 10:39 AM, Eric Blake wrote: > > On 7/16/19 10:04 AM, Richard W.M. Jones wrote: > >> The API changes from: > >> > >> int nbd_add_close_callback (struct nbd_handle *h, > >> nbd_close_callback cb, > >> void *user_data); > >> > >> to: > >> > >> int nbd_add_close_callback (struct nbd_handle *h, > >>...

On 7/16/19 10:04 AM, Richard W.M. Jones wrote: > The API changes from: > > int nbd_add_close_callback (struct nbd_handle *h, > nbd_close_callback cb, > void *user_data); > > to: > > int nbd_add_close_callback (struct nbd_handle *h, > void *user_data, >...

...| Flags n -> pr "uint32_t %s" n | Int n -> pr "int %s" n | Int64 n -> pr "int64_t %s" n @@ -3305,8 +3306,8 @@ let generate_include_libnbd_h () = pr "#define LIBNBD_HAVE_NBD_GET_ERRNO 1\n"; pr "\n"; pr "extern int nbd_add_close_callback (struct nbd_handle *h,\n"; - pr " void *user_data,\n"; - pr " nbd_close_callback cb);\n"; + pr " nbd_close_callback cb,\n"; + pr "...

** INCOMPLETE ** This is the generator change as discussed on the list already. The Python and OCaml bindings are not yet done. It passes all [C only] tests and valgrind. Note that nbd_add_close_callback is inconsistent with other closure types because it passes the user_data parameter after the function. (This is not caused by the current patch, it was already inconsistent). We decided that nbd_add_close_callback should be manually generated and not automatically generated because it should only...

...dings, right now we have to malloc() a C structure that tracks the Python Callable associated with any Closure, and currently don't free that C struct until nbd_close. Basically, we have: nbd_internal_py_aio_pread_structured data = malloc() nbd_aio_pread_structured(, chunk_wrapper, data) nbd_add_close_callback(data_free, data) nbd_internal_py_aio_pread_structured_callback data = malloc() nbd_aio_pread_structured_callback(, chunk_wrapper, callback_wrapper, data) nbd_add_close_callback(data_free, data) where there is no convenient way for the generator to insert cleanup for the data malloc'd in...

On 7/17/19 8:00 AM, Richard W.M. Jones wrote: > --- > .gitignore | 1 + > README | 2 + > configure.ac | 9 + > examples/Makefile.am | 22 ++ > examples/glib-main-loop.c | 511 ++++++++++++++++++++++++++++++++++++++ > 5 files changed, 545 insertions(+) Looks good. > > + revents = g_source_query_unix_fd

..._free_set_debug_callback_debug_fn corresponding to the debug_fn arg of nbd_set_debug_callback. Luckily they can all be generated along with the internal machinery to call them. Buffer lifetimes ---------------- Similar to the above, persistent buffers (BytesPersist*) can have lifetimes. Remove nbd_add_close_callback ----------------------------- The above changes (actually, just the closure change) lets us remove nbd_add_close_callback. Fixing callback / cookie problem -------------------------------- I think an easier way to fix this would be to simply detect the problematic situation and queue up the call...

...;; pr "extern const char *nbd_get_error (void);\n"; + pr "#define LIBNBD_HAVE_NBD_GET_ERROR 1\n"; + pr "\n"; pr "extern int nbd_get_errno (void);\n"; + pr "#define LIBNBD_HAVE_NBD_GET_ERRNO 1\n"; + pr "\n"; pr "extern int nbd_add_close_callback (struct nbd_handle *h,\n"; pr " nbd_close_callback cb, void *data);\n"; + pr "#define LIBNBD_HAVE_NBD_ADD_CLOSE_CALLBACK 1\n"; pr "\n"; List.iter ( - fun (name, { args; ret }) -> print_extern name args ret + fun...

This adds a C-only semi-private function for freeing various types of persistent data passed to libnbd. There are some similarities with nbd_add_close_callback which we removed in commit 7f191b150b52ed50098976309a6af883d245fc56. --- generator/generator | 46 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/generator/generator b/generator/generator index 55c4dfc..0ea6b61 100755 --- a/generator/generator +++ b/ge...

On Thu, Jul 11, 2019 at 09:35:02AM -0500, Eric Blake wrote: >On 7/11/19 9:23 AM, Martin Kletzander wrote: >> The callback (e.g. for `nbd_block_status`) now has a support for returning >> errors thanks to the last parameter (`int *error`), so it was switched to >> returning void. > >No, the callback still returns int. Where are you seeing it return >void, because

...n"; pr "\n"; List.iter (fun (n, i) -> pr "#define LIBNBD_%-30s %d\n" n i) constants; pr "\n"; @@ -3275,7 +3291,8 @@ let generate_include_libnbd_h () = pr "#define LIBNBD_HAVE_NBD_GET_ERRNO 1\n"; pr "\n"; pr "extern int nbd_add_close_callback (struct nbd_handle *h,\n"; - pr " nbd_close_callback cb, void *data);\n"; + pr " nbd_close_callback cb,\n"; + pr " void *user_data);\n"; pr "#define LI...

I think I've addressed everything that was raised in review. Some of the highlights: - Callbacks should be freed reliably along all exit paths. - There's a simple test of closure lifetimes. - I've tried to use VALID|FREE in all the places where I'm confident that it's safe and correct to do. There may be more places. Note this is an optimization and shouldn't

As before, but this one has working Python bindings. OCaml still TBD. Rich.

...sIn (n, _) -> pr " PyBuffer_Release (&%s);\n" n | BytesPersistIn _ | BytesOut _ | BytesPersistOut _ -> () - | Callback _ -> () - | CallbackPersist (n, _) -> - pr " /* This ensures the callback data is freed eventually. */\n"; - pr " nbd_add_close_callback (h, free, %s_data);\n" n | Flags _ -> () | Int _ -> () | Int64 _ -> () | Mutable _ -> () - | Opaque _ -> () + | OpaqueAndCallbacks _ -> () + | OpaqueAndCallbacksPersist (n, _) -> + pr " /* This ensures the callback data is freed eve...

v1 was here: https://www.redhat.com/archives/libguestfs/2019-July/thread.html#00231 The changes address everything that Eric picked up in his review of the first two patches. I have also added two more patches (4 and 5) which respectively fix docs and change int status -> unsigned status, as discussed. Passes make, check, check-valgrind. Rich.

This implements most of what I wrote here: https://www.redhat.com/archives/libguestfs/2019-July/msg00213.html

On 8/11/19 8:03 AM, Richard W.M. Jones wrote: > This adds a C-only semi-private function for freeing various types of > persistent data passed to libnbd. > > There are some similarities with nbd_add_close_callback which we > removed in commit 7f191b150b52ed50098976309a6af883d245fc56. > --- > generator/generator | 46 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 46 insertions(+) > > diff --git a/generator/generator b/generator/generator > index 55c4dfc..0ea6b61 100755...