Re: git: 94567c8641e2 - main - netstat: Resolve duplicate "dropped-packets" key from libxo output

On Fri, Sep 20, 2024 at 03:58:10PM +0000, Warner Losh wrote:
> The branch main has been updated by imp:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=94567c8641e235763b5b2926416d89d36654cde1
> 
> commit 94567c8641e235763b5b2926416d89d36654cde1
> Author:     Bram <bram@cbbg.nl>
> AuthorDate: 2024-07-23 08:57:42 +0000
> Commit:     Warner Losh <imp@FreeBSD.org>
> CommitDate: 2024-09-20 15:06:26 +0000
> 
>     netstat: Resolve duplicate "dropped-packets" key from libxo output
>     
>     The current libxo output uses the "dropped-packets" key for both incoming and
>     outgoing packets. This commit distinguishes between the two by adding an "in"
>     and "out" suffix. The original "dropped-packets" key is kept for backwards
>     compatibility for now.
>     
>     PR: 244589
>     Reviewed by: imp, zlei
>     Pull Request: https://github.com/freebsd/freebsd-src/pull/1331
> ---
>  usr.bin/netstat/if.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/usr.bin/netstat/if.c b/usr.bin/netstat/if.c
> index 172ea5324ccb..f0af785bce04 100644
> --- a/usr.bin/netstat/if.c
> +++ b/usr.bin/netstat/if.c
> @@ -501,8 +501,11 @@ intpr(void (*pfunc)(char *), int af)
>  		    IFA_STAT(ipackets), link|network, 1);
>  		show_stat("lu", nerr_len, "received-errors", IFA_STAT(ierrors),
>  		    link, 1);
> +		/* Below is kept for backwards compatibility. Will be removed in the future. */
>  		show_stat("lu", nerr_len, "dropped-packets", IFA_STAT(iqdrops),
>  		    link, 1);
> +		show_stat("lu", nerr_len, "dropped-packets-in", IFA_STAT(iqdrops),
> +		    link, 1);

This breaks plain netstat output, causing a bunch of network tests to
fail.  For instance, "netstat -Wf link -I re0" now prints an extra
column.

I think we should not bother with backwards compat unless libxo is
emitting structured output.  This can be implemented using the "e"
format modifier described in the xo_format modified, but I'm not sure
how to plumb it through show_stat().

Let's revert until this is fixed?

>  		if (bflag)
>  			show_stat("lu", nbyte_len, "received-bytes",
>  			    IFA_STAT(ibytes), link|network, 0);
> @@ -516,7 +519,7 @@ intpr(void (*pfunc)(char *), int af)
>  		show_stat("NRSlu", nerr_len, "collisions", IFA_STAT(collisions),
>  		    link, 1);
>  		if (dflag)
> -			show_stat("LSlu", nerr_len, "dropped-packets",
> +			show_stat("LSlu", nerr_len, "dropped-packets-out",
>  			    IFA_STAT(oqdrops), link, 1);
>  		xo_emit("\n");
>  
> @@ -705,8 +708,11 @@ loop:
>  	    new->ift_ip - old->ift_ip, 1, 1);
>  	show_stat("lu", 5, "received-errors",
>  	    new->ift_ie - old->ift_ie, 1, 1);
> +	/* Below is kept for backwards compatibility. Will be removed in the future. */
>  	show_stat("lu", 5, "dropped-packets",
>  	    new->ift_id - old->ift_id, 1, 1);
> +	show_stat("lu", 5, "dropped-packets-in",
> +	    new->ift_id - old->ift_id, 1, 1);
>  	show_stat("lu", 10, "received-bytes",
>  	    new->ift_ib - old->ift_ib, 1, 0);
>  	show_stat("lu", 10, "sent-packets",
> @@ -718,7 +724,7 @@ loop:
>  	show_stat("NRSlu", 5, "collisions",
>  	    new->ift_co - old->ift_co, 1, 1);
>  	if (dflag)
> -		show_stat("LSlu", 5, "dropped-packets",
> +		show_stat("LSlu", 5, "dropped-packets-out",
>  		    new->ift_od - old->ift_od, 1, 1);
>  	xo_close_instance("stats");
>  	xo_emit("\n");