iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Vadim Kochan]

Hi,

I'd like to make possible to generate plot info about class hierarchy
with qdisc, filters, stats info, but I see that all this staffs are
printed to 'FILE *fp' which makes this hard to implement and seems to me
that it should be changed to be printed to 'char *s' (memory safety
should be considered by asprintf or similar), so this is a big change
but all this is possible and I ready to do it, but before do it I'd like
to ask if this could be acceptable as idea.

BUT maybe someone can advise me easier solution ?

Regards,

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Florian Westphal]

Vadim Kochan <vadim4j@gmail.com> wrote:
> I'd like to make possible to generate plot info about class hierarchy
> with qdisc, filters, stats info, but I see that all this staffs are
> printed to 'FILE *fp' which makes this hard to implement and seems to me
> that it should be changed to be printed to 'char *s' (memory safety
> should be considered by asprintf or similar), so this is a big change
> but all this is possible and I ready to do it, but before do it I'd like
> to ask if this could be acceptable as idea.
> 
> BUT maybe someone can advise me easier solution ?

Would fmemopen/open_memstream(3) do what you want?

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Vadim Kochan]

On Wed, Jan 07, 2015 at 11:13:09PM +0100, Florian Westphal wrote:
> Vadim Kochan <vadim4j@gmail.com> wrote:
> > I'd like to make possible to generate plot info about class hierarchy
> > with qdisc, filters, stats info, but I see that all this staffs are
> > printed to 'FILE *fp' which makes this hard to implement and seems to me
> > that it should be changed to be printed to 'char *s' (memory safety
> > should be considered by asprintf or similar), so this is a big change
> > but all this is possible and I ready to do it, but before do it I'd like
> > to ask if this could be acceptable as idea.
> > 
> > BUT maybe someone can advise me easier solution ?
> 
> Would fmemopen/open_memstream(3) do what you want?
I briefly looked on it, and it might help, THANKS A LOT!

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Stephen Hemminger]

On Wed, 7 Jan 2015 23:53:31 +0200
Vadim Kochan <vadim4j@gmail.com> wrote:

> Hi,
> 
> I'd like to make possible to generate plot info about class hierarchy
> with qdisc, filters, stats info, but I see that all this staffs are
> printed to 'FILE *fp' which makes this hard to implement and seems to me
> that it should be changed to be printed to 'char *s' (memory safety
> should be considered by asprintf or similar), so this is a big change
> but all this is possible and I ready to do it, but before do it I'd like
> to ask if this could be acceptable as idea.
> 
> BUT maybe someone can advise me easier solution ?
> 
> Regards,
> --
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Rather than screen scraping tc command, why not use libmnl and get the
data you want programmatically.

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Vadim Kochan]

On Wed, Jan 07, 2015 at 03:08:28PM -0800, Stephen Hemminger wrote:
> On Wed, 7 Jan 2015 23:53:31 +0200
> Vadim Kochan <vadim4j@gmail.com> wrote:
> 
> > Hi,
> > 
> > I'd like to make possible to generate plot info about class hierarchy
> > with qdisc, filters, stats info, but I see that all this staffs are
> > printed to 'FILE *fp' which makes this hard to implement and seems to me
> > that it should be changed to be printed to 'char *s' (memory safety
> > should be considered by asprintf or similar), so this is a big change
> > but all this is possible and I ready to do it, but before do it I'd like
> > to ask if this could be acceptable as idea.
> > 
> > BUT maybe someone can advise me easier solution ?
> > 
> > Regards,
> > --
> > To unsubscribe from this list: send the line "unsubscribe netdev" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> Rather than screen scraping tc command, why not use libmnl and get the
> data you want programmatically.

I'd like to have text info from tc on screen and output on the other
data format to be the same, just only for this.

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Thomas Graf]

On 01/08/15 at 01:46am, Vadim Kochan wrote:
> I'd like to have text info from tc on screen and output on the other
> data format to be the same, just only for this.

Look at:
https://github.com/tgraf/libnl/blob/master/src/nl-tctree-list.c

It shows how to use an API to retrieve the information you want and
allows to pretty print tc entries.

Re: iproute2 tc: Print qdisc, stats, class, filter info to string rather than FILE

[Vadim Kochan]

On Thu, Jan 08, 2015 at 12:06:20AM +0000, Thomas Graf wrote:
> On 01/08/15 at 01:46am, Vadim Kochan wrote:
> > I'd like to have text info from tc on screen and output on the other
> > data format to be the same, just only for this.
> 
> Look at:
> https://github.com/tgraf/libnl/blob/master/src/nl-tctree-list.c
> 
> It shows how to use an API to retrieve the information you want and
> allows to pretty print tc entries.

OK, may be I am not clearly described what I am trying to do ...
So I think it might be useful to have an option in TC which would be
generate classes graph in plot format but keep the same text info as it
is printed on console by default. I just think to re-use the existing
code which prints that text info to console but use it for plot
generating. Do you think that this not right thing feature to be in TC
and it might better to have this separately from TC ?

Thanks,