On Wed, Sep 10, 2025 at 10:31:12PM +0300, Vladimir Sementsov-Ogievskiy wrote:
> The only realization, which may have incoming fds is
> qio_channel_socket_readv() (in io/channel-socket.c).
> qio_channel_socket_readv() do call (through
> qio_channel_socket_copy_fds()) qemu_socket_set_block() and
> qemu_set_cloexec() for each fd.
>
> Also, qio_channel_socket_copy_fds() is called at the end of
> qio_channel_socket_readv(), on success path.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
Maybe I'd just keep the io_readv() one, but drop the extra documents in
qio_channel_readv_full(), because that is almost a duplicate.
Meanwhile, we also have other higher level API that has the @fds
(qio_channel_readv_full_all_eof(), for example) that are not documented,
OTOH..
Totally no strong feelings.
Acked-by: Peter Xu <pet...@redhat.com>
> ---
> include/io/channel.h | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/include/io/channel.h b/include/io/channel.h
> index 12266256a8..c7f64506f7 100644
> --- a/include/io/channel.h
> +++ b/include/io/channel.h
> @@ -118,6 +118,15 @@ struct QIOChannelClass {
> size_t nfds,
> int flags,
> Error **errp);
> +
> + /*
> + * The io_readv handler must guarantee that all
> + * incoming fds are set BLOCKING (unless
> + * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag is set) and
> + * CLOEXEC (if available).
> + * @fds and @nfds are set only on success path, and untouched
> + * in case of errors.
> + */
> ssize_t (*io_readv)(QIOChannel *ioc,
> const struct iovec *iov,
> size_t niov,
> @@ -125,6 +134,7 @@ struct QIOChannelClass {
> size_t *nfds,
> int flags,
> Error **errp);
> +
> int (*io_close)(QIOChannel *ioc,
> Error **errp);
> GSource * (*io_create_watch)(QIOChannel *ioc,
> @@ -235,6 +245,13 @@ void qio_channel_set_name(QIOChannel *ioc,
> * was allocated. It is the callers responsibility
> * to call close() on each file descriptor and to
> * call g_free() on the array pointer in @fds.
> + * @fds allocated and set (and @nfds is set too)
> + * _only_ on success path. These parameters are
> + * untouched in case of errors.
> + * qio_channel_readv_full() guarantees that all
> + * incoming fds are set BLOCKING (unless
> + * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag
> + * is set) and CLOEXEC (if available).
> *
> * It is an error to pass a non-NULL @fds parameter
> * unless qio_channel_has_feature() returns a true
> --
> 2.48.1
>
--
Peter Xu
