Re: [PATCH ipvsadm 2/5] ipvsadm: fix ambiguous usage error message

	Hello,

On Sun, 12 Jan 2025, Jeremy Sowden wrote:

> If `-6` is used without `-f`, the usage error message is "-6 used before -f",
> which can be misconstrued as warning that both options were used but in the
> wrong order.
> 
> Change the option-parsing to allow `-6` to appear before `-f` and the error-
> message in the case that `-6` was used without `-f`.
> 
> Link: http://bugs.debian.org/610596
> Signed-off-by: Jeremy Sowden <[email protected]>
> ---
>  ipvsadm.c | 17 ++++++++++-------
>  1 file changed, 10 insertions(+), 7 deletions(-)
> 
> diff --git a/ipvsadm.c b/ipvsadm.c
> index 42f31a20e596..889128017bd1 100644
> --- a/ipvsadm.c
> +++ b/ipvsadm.c
> @@ -523,7 +523,7 @@ static int
>  parse_options(int argc, char **argv, struct ipvs_command_entry *ce,
>  	      unsigned long long *options, unsigned int *format)
>  {
> -	int c, parse;
> +	int c, parse, ipv6 = 0;
>  	poptContext context;
>  	char *optarg = NULL, sched_flags_arg[128];
>  	struct poptOption options_table[] = {
> @@ -829,12 +829,7 @@ parse_options(int argc, char **argv, struct ipvs_command_entry *ce,
>  			*format |= FMT_EXACT;
>  			break;
>  		case '6':
> -			if (ce->svc.fwmark) {
> -				ce->svc.af = AF_INET6;
> -				ce->svc.netmask = 128;
> -			} else {
> -				fail(2, "-6 used before -f\n");
> -			}
> +			ipv6 = 1;
>  			break;
>  		case 'o':
>  			set_option(options, OPTC_ONEPACKET);
> @@ -935,6 +930,14 @@ parse_options(int argc, char **argv, struct ipvs_command_entry *ce,
>  		return -1;
>  	}
>  
> +	if (ipv6) {
> +		if (ce->svc.fwmark) {
> +			ce->svc.af = AF_INET6;

	As ce->svc.af is set later after all options are processed,
the -M option will always see AF_INET in ce->svc.af ...

> +			ce->svc.netmask = 128;

	Now we override the value from -M, so we can not do
this here.

> +		} else
> +			fail(2, "-6 used without -f\n");
> +	}
> +
>  	if (ce->cmd == CMD_TIMEOUT) {
>  		char *optarg1, *optarg2;
>  
> -- 
> 2.45.2

Regards

--
Julian Anastasov <[email protected]>