sss_client: Re-check memcache after acquiring the lock Resolves: https://fedorahosted.org/sssd/ticket/2581 Reviewed-by: Michal Židek <mzidek@redhat.com>

sss_client: Use SAFEALIGN_COPY_<type> macros where appropriate. resolves: https://fedorahosted.org/sssd/ticket/1359

Fix errors reported by rpmlint

sss_client: shared memory cache passwd map support

NSS: Add sss_readrep_copy_string There were many places in the client code where we were duplicating a loop to copy data in from the response buffer. This patch turns those loops into a function for easier maintenance and easier-to-read *readrep() routines.

NSS: Validate input string lengths Also fixes a return value bug where we were returning errno error codes instead of nss_status codes. Fixes https://fedorahosted.org/sssd/ticket/1135

sss_client: make code thread-safe Add mutexes around nss operations and serialize them. This is necessary because nss operations may have global state. For pam it is sufficient to protect socket operations instead. As pam functions use only the provided pam handler. Fixes: https://fedorahosted.org/sssd/ticket/640

Rename group.c and passwd.c for clarity Prefixing group.c and passwd.c with "nss_" similar to the way the PAM client sources are prefixed with "pam_"