[SSSD] [sssd PR#46][opened] sss_client: Defer thread cancellation until completion of nss/pam operations

[fidencio]

URL: https://github.com/SSSD/sssd/pull/46
Author: HouzuoGuo
 Title: #46: sss_client: Defer thread cancellation until completion of nss/pam operations
Action: opened

PR body:
"""
https://fedorahosted.org/sssd/ticket/3156

The client code is not cancellation-safe, an application which has cancelled an NSS operation
will experience subtle bugs, hence thread cancellation is deferred until completion of client
operations.
"""

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/46/head:pr46
git checkout pr46