[PATCH 1/3] gaiconf_init: Refactor some bits for readability

[DJ Delorie]

Siddhesh Poyarekar via Libc-alpha <libc-alpha@sourceware.org> writes:
> Split out line processing for `label`, `precedence` and `scopev4` into
> separate functions instead of the gotos.

LGTM.
Reviewed-by: DJ Delorie <dj@redhat.com>

> diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
> +static bool
> +add_prefixlist (struct prefixlist **listp, size_t *lenp, bool *nullbitsp,
> +		char *val1, char *val2, char **pos)
> +{
> +  struct in6_addr prefix;
> +  unsigned long int bits;
> +  unsigned long int val;
> +  char *endp;
> +
> +  bits = 128;
> +  __set_errno (0);
> +  char *cp = strchr (val1, '/');
> +  if (cp != NULL)
> +    *cp++ = '\0';
> +  *pos = cp;
> +  if (inet_pton (AF_INET6, val1, &prefix)
> +      && (cp == NULL
> +	  || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
> +	  || errno != ERANGE)
> +      && *endp == '\0'
> +      && bits <= 128
> +      && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
> +	  || errno != ERANGE)
> +      && *endp == '\0'
> +      && val <= INT_MAX)
> +    {
> +      struct prefixlist *newp = malloc (sizeof (*newp));
> +      if (newp == NULL)
> +	return false;
> +
> +      memcpy (&newp->entry.prefix, &prefix, sizeof (prefix));
> +      newp->entry.bits = bits;
> +      newp->entry.val = val;
> +      newp->next = *listp;
> +      *listp = newp;
> +      ++*lenp;
> +      *nullbitsp |= bits == 0;
> +    }
> +  return true;
> +}

Matches removed code, ok.

> +static bool
> +add_scopelist (struct scopelist **listp, size_t *lenp, bool *nullbitsp,
> +	       const struct in6_addr *prefixp, unsigned long int bits,
> +	       unsigned long int val)
> +{
> +  struct scopelist *newp = malloc (sizeof (*newp));
> +  if (newp == NULL)
> +    return false;
> +
> +  newp->entry.netmask = htonl (bits != 96 ? (0xffffffff << (128 - bits)) : 0);
> +  newp->entry.addr32 = (prefixp->s6_addr32[3] & newp->entry.netmask);
> +  newp->entry.scope = val;
> +  newp->next = *listp;
> +  *listp = newp;
> +  ++*lenp;
> +  *nullbitsp |= bits == 96;
> +
> +  return true;
> +}

matches removed code, ok.

>  static void
>  gaiconf_init (void)
> @@ -1836,55 +1896,17 @@ gaiconf_init (void)
>  	  /*  Ignore the rest of the line.  */
>  	  *cp = '\0';
>  
> -	  struct prefixlist **listp;
> -	  size_t *lenp;
> -	  bool *nullbitsp;
>  	  switch (cmdlen)
>  	    {
>  	    case 5:
>  	      if (strcmp (cmd, "label") == 0)
>  		{
> +		  if (!add_prefixlist (&labellist, &nlabellist,
> +				       &labellist_nullbits, val1, val2, &cp))
>  		    {
> +		      free (line);
> +		      fclose (fp);
> +		      goto no_file;
>  		    }

Ok.

> -		  struct in6_addr prefix;
> -		  unsigned long int bits;
> -		  unsigned long int val;
> -		  char *endp;
> -
> -		  listp = &labellist;
> -		  lenp = &nlabellist;
> -		  nullbitsp = &labellist_nullbits;
> -
> -		new_elem:
> -		  bits = 128;
> -		  __set_errno (0);
> -		  cp = strchr (val1, '/');
> -		  if (cp != NULL)
> -		    *cp++ = '\0';
> -		  if (inet_pton (AF_INET6, val1, &prefix)
> -		      && (cp == NULL
> -			  || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
> -			  || errno != ERANGE)
> -		      && *endp == '\0'
> -		      && bits <= 128
> -		      && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
> -			  || errno != ERANGE)
> -		      && *endp == '\0'
> -		      && val <= INT_MAX)
>  		    {
> -		      struct prefixlist *newp = malloc (sizeof (*newp));
> -		      if (newp == NULL)
> -			{
> -			  free (line);
> -			  fclose (fp);
> -			  goto no_file;
> -			}
> -
> -		      memcpy (&newp->entry.prefix, &prefix, sizeof (prefix));
> -		      newp->entry.bits = bits;
> -		      newp->entry.val = val;
> -		      newp->next = *listp;
> -		      *listp = newp;
> -		      ++*lenp;
> -		      *nullbitsp |= bits == 0;

Matches extracted code, ok.

>  		    }
>  		}
>  	      break;
> @@ -1926,27 +1948,14 @@ gaiconf_init (void)
>  			  && *endp == '\0'
>  			  && val <= INT_MAX)
>  			{

> +			  if (!add_scopelist (&scopelist, &nscopelist,
> +					      &scopelist_nullbits, &prefix,
> +					      bits, val))

Ok.

>  			    {
>  			      free (line);
>  			      fclose (fp);
>  			      goto no_file;
>  			    }
> -			  struct scopelist *newp;
> -			new_scope:
> -			  newp = malloc (sizeof (*newp));
> -			  if (newp == NULL)
> - ...
> -
> -			  newp->entry.netmask = htonl (bits != 96
> -						       ? (0xffffffff
> -							  << (128 - bits))
> -						       : 0);
> -			  newp->entry.addr32 = (prefix.s6_addr32[3]
> -						& newp->entry.netmask);
> -			  newp->entry.scope = val;
> -			  newp->next = scopelist;
> -			  scopelist = newp;
> -			  ++nscopelist;
> -			  scopelist_nullbits |= bits == 96;

Matches extracted code, ok.

>  		    }
>  		  else if (inet_pton (AF_INET, val1, &prefix.s6_addr32[3])
> @@ -1960,8 +1969,14 @@ gaiconf_init (void)
>  			   && *endp == '\0'
>  			   && val <= INT_MAX)
>  		    {
> -		      bits += 96;
> -		      goto new_scope;
> +		      if (!add_scopelist (&scopelist, &nscopelist,
> +					  &scopelist_nullbits, &prefix,
> +					  bits + 96, val))
> +			{
> +			  free (line);
> +			  fclose (fp);
> +			  goto no_file;
> +			}

Ok.

> @@ -1969,10 +1984,14 @@ gaiconf_init (void)
>  	    case 10:
>  	      if (strcmp (cmd, "precedence") == 0)
>  		{
> -		  listp = &precedencelist;
> -		  lenp = &nprecedencelist;
> -		  nullbitsp = &precedencelist_nullbits;
> -		  goto new_elem;
> +		  if (!add_prefixlist (&precedencelist, &nprecedencelist,
> +				       &precedencelist_nullbits, val1, val2,
> +				       &cp))
> +		    {
> +		      free (line);
> +		      fclose (fp);
> +		      goto no_file;
> +		    }

Ok.