[PATCH 1/3] networkcommon_conf: Use g_autofree where possible

[Laine Stump]

On 2/23/21 12:24 PM, Kristina Hanicova wrote:
> Signed-off-by: Kristina Hanicova <khanicov at redhat.com>
> ---
>   src/conf/networkcommon_conf.c | 14 +++++---------
>   1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/src/conf/networkcommon_conf.c b/src/conf/networkcommon_conf.c
> index 26eeb6dbda..e82dbc3d3d 100644
> --- a/src/conf/networkcommon_conf.c
> +++ b/src/conf/networkcommon_conf.c
> @@ -228,9 +228,10 @@ virNetDevIPRouteParseXML(const char *errorDetail,
>   
>       virNetDevIPRoutePtr def = NULL;
>       VIR_XPATH_NODE_AUTORESTORE(ctxt)
> -    char *family = NULL;
> -    char *address = NULL, *netmask = NULL;
> -    char *gateway = NULL;
> +    g_autofree char *family = NULL;
> +    g_autofree char *address = NULL;
> +    g_autofree char *netmask = NULL;
> +    g_autofree char *gateway = NULL;
>       unsigned long prefix = 0, metric = 0;
>       int prefixRc, metricRc;
>       bool hasPrefix = false;
> @@ -276,10 +277,6 @@ virNetDevIPRouteParseXML(const char *errorDetail,
>                                    hasMetric);
>   
>    cleanup:
> -    VIR_FREE(family);
> -    VIR_FREE(address);
> -    VIR_FREE(netmask);
> -    VIR_FREE(gateway);
>       return def;
>   }
>   
> @@ -287,7 +284,7 @@ int
>   virNetDevIPRouteFormat(virBufferPtr buf,
>                          const virNetDevIPRoute *def)
>   {
> -    char *addr = NULL;
> +    g_autofree char *addr = NULL;
>   
>       virBufferAddLit(buf, "<route");
>   
> @@ -311,7 +308,6 @@ virNetDevIPRouteFormat(virBufferPtr buf,
>       if (!(addr = virSocketAddrFormat(&def->gateway)))
>           return -1;
>       virBufferAsprintf(buf, " gateway='%s'", addr);
> -    VIR_FREE(addr);

This one is a bit more complicated, because "addr" is re-used after 
being freed (twice - first used for address, then for netmask, and 
finally for gateway), and we've made the rule that an auto-freed pointer 
should never be VIR_FREED

So instead of just making the existing pointer g_autofree and 
eliminating its final free, we need to create separate pointers for each 
use:

g_autofree char *address = NULL;
g_autofree char *netmask = NULL;
g_autofree char *gataeway = NULL;

and then use each in the appropriate place.

(if we're lucky, the compiler/optimizer will even be smart enough to 
figure out that the three things are never used at the same time (? 
depending on when the call to the autofree function is injected), and 
internally merge them into a single variable.)

>   
>       if (def->has_metric && def->metric > 0)
>           virBufferAsprintf(buf, " metric='%u'", def->metric);
>