Re: [PATCH] net/slirp: introduce slirp_os_socket to stay compatible with libslirp past 4.8.0

[Samuel Thibault <samuel.thibault@gnu.org>]

Hello,

Michael Tokarev, le sam. 05 oct. 2024 10:07:53 +0300, a ecrit:
> libslirp introduced new typedef after 4.8.0, slirp_os_socket, which
> is defined to SOCKET on windows, which, in turn, is a 64bit number.
> qemu uses int, so callback function prorotypes changed.

I have fixed the code in upstream libslirp, to avoid breaking the API
and ABI, and instead provide new functions & methods so that
qemu/libslirp can upgrade smoothly.

> Introduce
> slirp_os_socket locally if SLIRP_INVALID_SOCKET is not defined (this
> define has been introduced together wiht slirp_os_socket type), for
> libslirp <= 4.8.0, and use it in callback function definitions.
> 
> Link: https://gitlab.freedesktop.org/slirp/libslirp/-/commit/72f85005a2307fd0961543e3cea861ad7a4d201e
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2603
> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
> ---
>  net/slirp.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/net/slirp.c b/net/slirp.c
> index eb9a456ed4..fa07268cf4 100644
> --- a/net/slirp.c
> +++ b/net/slirp.c
> @@ -98,6 +98,10 @@ typedef struct SlirpState {
>      GSList *fwd;
>  } SlirpState;
>  
> +#ifndef SLIRP_INVALID_SOCKET /* after 4.8.0 */

You can instead use SLIRP_CONFIG_VERSION_MAX >= 6, and if so set
cfg.version to 6 and use the new fields and functions.

> +typedef int slirp_os_socket;
> +#endif
> +
>  static struct slirp_config_str *slirp_configs;
>  static QTAILQ_HEAD(, SlirpState) slirp_stacks =
>      QTAILQ_HEAD_INITIALIZER(slirp_stacks);
> @@ -247,7 +251,7 @@ static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
>      timer_mod(&t->timer, expire_timer);
>  }
>  
> -static void net_slirp_register_poll_fd(int fd, void *opaque)
> +static void net_slirp_register_poll_fd(slirp_os_socket fd, void *opaque)
>  {
>  #ifdef WIN32
>      AioContext *ctxt = qemu_get_aio_context();
> @@ -260,7 +264,7 @@ static void net_slirp_register_poll_fd(int fd, void *opaque)
>  #endif
>  }
>  
> -static void net_slirp_unregister_poll_fd(int fd, void *opaque)
> +static void net_slirp_unregister_poll_fd(slirp_os_socket fd, void *opaque)
>  {
>  #ifdef WIN32
>      if (WSAEventSelect(fd, NULL, 0) != 0) {
> @@ -314,7 +318,7 @@ static int slirp_poll_to_gio(int events)
>      return ret;
>  }
>  
> -static int net_slirp_add_poll(int fd, int events, void *opaque)
> +static int net_slirp_add_poll(slirp_os_socket fd, int events, void *opaque)
>  {
>      GArray *pollfds = opaque;
>      GPollFD pfd = {
> -- 
> 2.39.5