Re: [Qemu-devel] [PATCH] slirp: Allow to disable IPv4 or IPv6

[Thomas Huth <thuth@redhat.com>]

On 20.03.2016 12:39, Samuel Thibault wrote:
> Make net=0.0.0.0 disable IPv4 and ip6-net=:: disable IPv6, so the user can
> setup IPv4-only and IPv6-only network environments.
> 
> Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
> ---
>  net/slirp.c       |  8 +++++---
>  qapi-schema.json  |  4 ++--
>  qemu-options.hx   |  7 ++++---
>  slirp/ip6.h       |  9 +++++++++
>  slirp/ip6_icmp.c  | 10 ++++++++++
>  slirp/ip6_input.c |  6 ++++++
>  slirp/ip_input.c  |  5 +++++
>  slirp/slirp.c     |  5 +++++
>  8 files changed, 46 insertions(+), 8 deletions(-)
> 
> diff --git a/net/slirp.c b/net/slirp.c
> index 95239bc..3151d4a 100644
> --- a/net/slirp.c
> +++ b/net/slirp.c
> @@ -244,13 +244,15 @@ static int net_slirp_init(NetClientState *peer, const char *model,
>  
>  #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
>      /* No inet_pton helper before Vista... */
> -    if (vprefix6) {
> +    if (vprefix6 && strcmp(vprefix6, "::")) {
>          /* Unsupported */
>          return -1;
>      }
>      memset(&ip6_prefix, 0, sizeof(ip6_prefix));
> -    ip6_prefix.s6_addr[0] = 0xfe;
> -    ip6_prefix.s6_addr[1] = 0xc0;
> +    if (!vprefix6) {
> +        ip6_prefix.s6_addr[0] = 0xfe;
> +        ip6_prefix.s6_addr[1] = 0xc0;
> +    }
>  #else
>      if (!vprefix6) {
>          vprefix6 = "fec0::";
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 88f9b81..69eb6e7 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -2427,7 +2427,7 @@
>  #
>  # @ip: #optional legacy parameter, use net= instead
>  #
> -# @net: #optional IP address and optional netmask
> +# @net: #optional IP address and optional netmask. Set to 0.0.0.0 to disable IPv4 completely
>  #
>  # @host: #optional guest-visible address of the host
>  #
> @@ -2443,7 +2443,7 @@
>  # @dnssearch: #optional list of DNS suffixes to search, passed as DHCP option
>  #             to the guest
>  #
> -# @ip6-prefix: #optional IPv6 network prefix (default is fec0::) (since 2.6)
> +# @ip6-prefix: #optional IPv6 network prefix. Set to :: to disable IPv6 completely (default is fec0::) (since 2.6)

The new lines here seem to be longer than 80 characters ... I think you
should wrap them.
Apart from that, the patch looks fine to me.

 Thomas