Fixes BZ #15339.
NSS_STATUS_UNAVAIL may mean that a necessary input resource is not
available. This could occur in a number of cases including when the
network is down, system runs out of file descriptors, etc. The
correct differentiator in such a case is the h_errno, which gives the
nature of failure. In case of failures other than a simple 'not
found', we set h_errno as NETDB_INTERNAL and let errno be the
identifier for the exact error.
When glibc is built with --enable-static-nss, the warning that
using NSS symbols requires the nss shared objects to be present
is no longer true, as those symbols are built into libc. Suppress
the warning for those symbols by providing a new macro
(nss_interface_function) for the NSS functions that is defined as
static_link_warning in the normal case, and empty for static NSS.
* sysdeps/posix/getaddrinfo.c (default_scopes): Map RFC 1918
* addresses
to global scope.
* posix/tst-rfc3484.c: Verify 10/8, 172.16/12 and 196.128/16
addresses are in the same scope as 192.0.2/24.
* posix/gai.conf: Document new scope table defaults.
limit
[BZ #14307]
* sysdeps/posix/getaddrinfo.c (gaih_inet): Increase the size of
the temporary buffer used to invoke __gethostbyname2_r,
__gethostbyaddr_r and gethostbyname4_r to make room for struct
host_data / struct gaih_addrtuple.
* resolv/nss_dns/dns-host.c (global scope): Move definition of
implementation constants MAX_NR_ALIASES and MAX_NR_ADDRS to
header file nss/nsswitch.h.
* nss/nsswitch.h (global scope): Add definition of implementation
constants MAX_NR_ALIASES and MAX_NR_ADDRS (moved from
resolv/nss_dns/dns-host.c).
Whenever getaddrinfo needed network interface information it used the
netlink interface to read the information every single time. The
problem is that this information can change at any time.
The patch implements monitoring of the network interfaces through
nscd. If no change is detected the previously read information can
be reused (which is the norm). This timestamp information is also
made available to other processes using the shared memory segment
between nscd and those processes.
