Re: [pve-devel] [PATCH common] fix #3153: INotify: adding interface comment to inet6 section when this is the only section

[Thomas Lamprecht <t.lamprecht@proxmox.com>]

On 25.06.21 12:48, Lorenz Stechauner wrote:
> Signed-off-by: Lorenz Stechauner <l.stechauner@proxmox.com>
> ---
>  src/PVE/INotify.pm | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/src/PVE/INotify.pm b/src/PVE/INotify.pm
> index 562a243..ce1efd1 100644
> --- a/src/PVE/INotify.pm
> +++ b/src/PVE/INotify.pm
> @@ -1156,6 +1156,12 @@ sub __read_etc_network_interfaces {
>  	$d->{method} = 'manual' if !$d->{method};
>  	$d->{method6} = 'manual' if !$d->{method6};
>  
> +	if ($d->{comments6}) {
> +	    $d->{comments} = '' if !defined($d->{comments});
> +	    $d->{comments} .= $d->{comments6};
> +	    $d->{comments6} = undef;

rather than setting it to `undef`, in which case the hash element still exists, use
`delete`, which also returns the value.


So this could be:

if (my $comments6 = delete $d->{comments6}) {
    $d->{comments} = ($d->{comments}) // '') . $comments6;
}

Shorter and also more correct/robust.

> +	}
> +
>  	$d->{families} ||= ['inet'];
>      }
>  
> @@ -1242,7 +1248,7 @@ sub __interface_to_string {
>      my $done = { type => 1, priority => 1, method => 1, active => 1, exists => 1,
>  		 comments => 1, autostart => 1, options => 1,
>  		 address => 1, netmask => 1, gateway => 1, broadcast => 1,
> -		 method6 => 1, families => 1, options6 => 1,
> +		 method6 => 1, families => 1, options6 => 1, comments6 => 1,
>  		 address6 => 1, netmask6 => 1, gateway6 => 1, broadcast6 => 1, 'uplink-id' => 1 };
>  
>      if (!$first_block) {
> @@ -1733,6 +1739,12 @@ NETWORKDOC
>  	    }
>  	}
>  
> +	# if 'inet6' is the only family or is at least a family in use
> +	if ($d->{families}[0] eq 'inet6') {

shouldn't that include a length check like `scalar($d->{families}->@*) == 0` to be more safe/robust,
as else inet6 could be just be first by chance (did not really checked the context though)

> +	    $d->{comments6} = $d->{comments};
> +	    $d->{comments} = undef;

see above regarding use of delete

> +	}
> +
>  	my $i = 0; # some options should be printed only once
>  	$raw .= __interface_to_string($iface, $d, $_, !$i++, $ifupdown2) foreach @{$d->{families}};
>      }
>