Re: [PATCH] sepolgen: Use key function in sort()

From: Joshua Brindle <brindle@quarksecurity.com>
To: Petr Lautrbach <plautrba@redhat.com>
Cc: selinux@tycho.nsa.gov
Subject: Re: [PATCH] sepolgen: Use key function in sort()
Date: Fri, 13 Nov 2015 10:46:47 -0500	[thread overview]
Message-ID: <564605E7.60804@quarksecurity.com> (raw)
In-Reply-To: <1447415529-7588-1-git-send-email-plautrba@redhat.com>

Petr Lautrbach wrote:
> In Py3.0, the cmp parameter in sort() function was removed and key keyword is
> available since Py2.4.
>
> Fixes: # cat avc.log | audit2allow -R
> Traceback (most recent call last):
>    File "/usr/bin/audit2allow", line 363, in<module>
>      app.main()
>    File "/usr/bin/audit2allow", line 351, in main
>      self.__output()
>    File "/usr/bin/audit2allow", line 308, in __output
>      g.set_gen_refpol(ifs, perm_maps)
>    File "/usr/lib64/python3.4/site-packages/sepolgen/policygen.py", line 101, in set_gen_refpol
>      self.ifgen = InterfaceGenerator(if_set, perm_maps)
>    File "/usr/lib64/python3.4/site-packages/sepolgen/policygen.py", line 353, in __init__
>      self.hack_check_ifs(ifs)
>    File "/usr/lib64/python3.4/site-packages/sepolgen/policygen.py", line 365, in hack_check_ifs
>      params.sort(param_comp)
> TypeError: must use keyword argument for key function
>
> Signed-off-by: Petr Lautrbach<plautrba@redhat.com>

Thanks, Applied.

> ---
>   sepolgen/src/sepolgen/policygen.py | 9 ++-------
>   1 file changed, 2 insertions(+), 7 deletions(-)
>
> diff --git a/sepolgen/src/sepolgen/policygen.py b/sepolgen/src/sepolgen/policygen.py
> index 4438a11..34c8401 100644
> --- a/sepolgen/src/sepolgen/policygen.py
> +++ b/sepolgen/src/sepolgen/policygen.py
> @@ -36,8 +36,6 @@ from . import access
>   from . import interfaces
>   from . import matching
>   from . import util
> -if util.PY3:
> -    from .util import cmp
>   # Constants for the level of explanation from the generation
>   # routines
>   NO_EXPLANATION    = 0
> @@ -278,15 +276,12 @@ def explain_access(av, ml=None, verbosity=SHORT_EXPLANATION):
>           explain_interfaces()
>       return s
>
> -def param_comp(a, b):
> -    return cmp(b.num, a.num)
> -
>   def call_interface(interface, av):
>       params = []
>       args = []
>
>       params.extend(interface.params.values())
> -    params.sort(param_comp)
> +    params.sort(key=lambda param: param.num, reverse=True)
>
>       ifcall = refpolicy.InterfaceCall()
>       ifcall.ifname = interface.name
> @@ -321,7 +316,7 @@ class InterfaceGenerator:
>           for x in ifs.interfaces.values():
>               params = []
>               params.extend(x.params.values())
> -            params.sort(param_comp)
> +            params.sort(key=lambda param: param.num, reverse=True)
>               for i in range(len(params)):
>                   # Check that the paramater position matches
>                   # the number (e.g., $1 is the first arg). This