Re: [Qemu-devel] [PATCH 2/5] slirp: Split get_dns_addr

[Thomas Huth <thuth@redhat.com>]

On 29.03.2016 01:44, Samuel Thibault wrote:
> Separate get_dns_addr into get_dns_addr_cached and get_dns_addr_resolv_conf
> to make conversion to IPv6 easier.
> 
> Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
> ---
>  slirp/slirp.c | 53 ++++++++++++++++++++++++++++++++++-------------------
>  1 file changed, 34 insertions(+), 19 deletions(-)
> 
> diff --git a/slirp/slirp.c b/slirp/slirp.c
> index 6256c89..2f0d3a3 100644
> --- a/slirp/slirp.c
> +++ b/slirp/slirp.c
> @@ -108,7 +108,28 @@ static void winsock_cleanup(void)
>  
>  static struct stat dns_addr_stat;
>  
> -int get_dns_addr(struct in_addr *pdns_addr)
> +static int get_dns_addr_cached(struct in_addr *pdns_addr)
> +{
> +    struct stat old_stat;
> +    if ((curtime - dns_addr_time) < TIMEOUT_DEFAULT) {

Cosmetic nit: While you're at it, you could also remove the superfluous
parentheses here.

> +        *pdns_addr = dns_addr;
> +        return 0;
> +    }
> +    old_stat = dns_addr_stat;
> +    if (stat("/etc/resolv.conf", &dns_addr_stat) != 0) {
> +        return -1;
> +    }
> +    if ((dns_addr_stat.st_dev == old_stat.st_dev)
> +        && (dns_addr_stat.st_ino == old_stat.st_ino)
> +        && (dns_addr_stat.st_size == old_stat.st_size)
> +        && (dns_addr_stat.st_mtime == old_stat.st_mtime)) {

dito.

> +        *pdns_addr = dns_addr;
> +        return 0;
> +    }
> +    return 1;
> +}
> +
> +static int get_dns_addr_resolv_conf(struct in_addr *pdns_addr)
>  {
>      char buff[512];
>      char buff2[257];
> @@ -116,24 +137,6 @@ int get_dns_addr(struct in_addr *pdns_addr)
>      int found = 0;
>      struct in_addr tmp_addr;
>  
> -    if (dns_addr.s_addr != 0) {
> -        struct stat old_stat;
> -        if ((curtime - dns_addr_time) < TIMEOUT_DEFAULT) {
> -            *pdns_addr = dns_addr;
> -            return 0;
> -        }
> -        old_stat = dns_addr_stat;
> -        if (stat("/etc/resolv.conf", &dns_addr_stat) != 0)
> -            return -1;
> -        if ((dns_addr_stat.st_dev == old_stat.st_dev)
> -            && (dns_addr_stat.st_ino == old_stat.st_ino)
> -            && (dns_addr_stat.st_size == old_stat.st_size)
> -            && (dns_addr_stat.st_mtime == old_stat.st_mtime)) {
> -            *pdns_addr = dns_addr;
> -            return 0;
> -        }
> -    }
> -
>      f = fopen("/etc/resolv.conf", "r");
>      if (!f)
>          return -1;
> @@ -173,6 +176,18 @@ int get_dns_addr(struct in_addr *pdns_addr)
>      return 0;
>  }
>  
> +int get_dns_addr(struct in_addr *pdns_addr)
> +{
> +    if (dns_addr.s_addr != 0) {
> +        int ret;
> +        ret = get_dns_addr_cached(pdns_addr);
> +        if (ret <= 0) {
> +            return ret;
> +        }
> +    }
> +    return get_dns_addr_resolv_conf(pdns_addr);
> +}
> +
>  #endif
>  
>  static void slirp_init_once(void)
> 

Reviewed-by: Thomas Huth <thuth@redhat.com>