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Subject: Re: [hwloc-devel] Feature request: bitmap ASCII list representation
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2011-01-04 07:00:40


Le 04/01/2011 12:50, Bernd Kallies a écrit :
> Dear all,
>
> the current bitmap API of hwloc 1.1 supports input/output for bitmaps
> using strings that represent a map as hex words. The functions are
> hwloc_bitmap_snprintf, hwloc_bitmap_sscanf and the like.
>
> Linux cpusets in addition support an "ASCII list representation" of
> bitmaps, like 0-15,32-47. This is much easier to read and to write.
>
> I suggest to add corresponding functions to the hwloc bitmap C API.
>

Hello Bernd,

Right, this has been in the TODO list for a while, I haven't had time to
work on it yet.

> Note that there also exists libcpuset and libbitmask in some Linux
> distributions. These are originally from SGI. There exist the functions
> bitmask_displayhex, bitmask_displaylist, bitmask_parsehex,
> bitmask_parselist.
>

Both are LGPL unfortunately, we can't use this in hwloc (BSD).

> I added something like that to the most recent Sys::Hwloc Perl wrapper,
> which is currently found at
>
> http://www.cpan.org/modules/by-authors/id/B/BK/BKA/Sys-Hwloc-0.07.tar.gz
>
> The code for list input/output of hwloc bitmaps was adapted from recent
> linux kernel code, see e.g.
> http://lxr.free-electrons.com/source/lib/bitmap.c
> (functions bitmap_scnlistprintf, bitmap_parselist).
>

This is GPL as well.

The code isn't hard to write anyway, I'll try to do it for 1.2. I guess
it would be hwloc_bitmap_list_snprintf/sscanf (we already have
hwloc_bitmap_taskset_snprintf/sccanf for taskset format printing/parsing).

Brice