[SSSD] [sssd PR#710][opened] data_provider_fo: fix error in hostname retrieval

[alexey-tikhonov]

URL: https://github.com/SSSD/sssd/pull/710
Author: alexey-tikhonov
Title: #710: data_provider_fo: fix error in hostname retrieval
Action: opened

PR body:
"""
Fixed off-by-one error in gethostname() param

Resolves:
https://pagure.io/SSSD/sssd/issue/3865
"""

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/710/head:pr710
git checkout pr710

[centos-ci]

URL: https://github.com/SSSD/sssd/pull/710
Title: #710: data_provider_fo: fix error in hostname retrieval

centos-ci commented:
"""
Can one of the admins verify this patch?
"""

See the full comment at https://github.com/SSSD/sssd/pull/710#issuecomment-445312552

[jhrozek]

URL: https://github.com/SSSD/sssd/pull/710
Title: #710: data_provider_fo: fix error in hostname retrieval

jhrozek commented:
"""
(Your patches should no longer by gated by centos CI)
"""

See the full comment at https://github.com/SSSD/sssd/pull/710#issuecomment-445745904

[jhrozek]

URL: https://github.com/SSSD/sssd/pull/710
Title: #710: data_provider_fo: fix error in hostname retrieval

jhrozek commented:
"""
add to whitelist
"""

See the full comment at https://github.com/SSSD/sssd/pull/710#issuecomment-445745812

[jhrozek]

URL: https://github.com/SSSD/sssd/pull/710
Title: #710: data_provider_fo: fix error in hostname retrieval

jhrozek commented:
"""
I think this would fix the error, but I have two more questions:
1) Do you agree it would be nice to fix all gethostname() calls in a similar manner?
2) I like the sizeof(arr)/sizeof(elem) approach you took. I also now noticed, with the help of some git grep that we have this already defined as a macro called `N_ELEMENTS`, but only in the test code. Do you think it would make sense to move the macro to e.g. utils.h and reuse it outside the test code?
"""

See the full comment at https://github.com/SSSD/sssd/pull/710#issuecomment-445773513