[Slirp] [PATCH 2/6] dhcpv6: use slirp_fmt()

[Philippe Mathieu-Daudé]

On 1/27/20 10:24 AM, marcandre.lureau at redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau at redhat.com>
> 
> Warn if result is truncated, return bytes actually written (excluding \0).
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau at redhat.com>
> Reviewed-by: Samuel Thibault <samuel.thibault at ens-lyon.org>
> ---
>   src/dhcpv6.c | 13 ++++++-------
>   1 file changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/src/dhcpv6.c b/src/dhcpv6.c
> index ce5f203..77b451b 100644
> --- a/src/dhcpv6.c
> +++ b/src/dhcpv6.c
> @@ -179,13 +179,12 @@ static void dhcpv6_info_request(Slirp *slirp, struct sockaddr_in6 *srcsas,
>           *resp++ = OPTION_BOOTFILE_URL >> 8; /* option-code high byte */
>           *resp++ = OPTION_BOOTFILE_URL; /* option-code low byte */
>           smaxlen = (uint8_t *)m->m_data + slirp->if_mtu - (resp + 2);
> -        slen = snprintf((char *)resp + 2, smaxlen,
> -                        "tftp://[%02x%02x:%02x%02x:%02x%02x:%02x%02x:"
> -                        "%02x%02x:%02x%02x:%02x%02x:%02x%02x]/%s",
> -                        sa[0], sa[1], sa[2], sa[3], sa[4], sa[5], sa[6], sa[7],
> -                        sa[8], sa[9], sa[10], sa[11], sa[12], sa[13], sa[14],
> -                        sa[15], slirp->bootp_filename);
> -        slen = MIN(slen, smaxlen);
> +        slen = slirp_fmt((char *)resp + 2, smaxlen,
> +                         "tftp://[%02x%02x:%02x%02x:%02x%02x:%02x%02x:"
> +                         "%02x%02x:%02x%02x:%02x%02x:%02x%02x]/%s",
> +                         sa[0], sa[1], sa[2], sa[3], sa[4], sa[5], sa[6], sa[7],
> +                         sa[8], sa[9], sa[10], sa[11], sa[12], sa[13], sa[14],
> +                         sa[15], slirp->bootp_filename);
>           *resp++ = slen >> 8; /* option-len high byte */
>           *resp++ = slen; /* option-len low byte */
>           resp += slen;
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd at redhat.com>