Private futexes are a recent kernel addition: faster futexes that cannot be
shared between processes. This patch uses them by default, unless the PROCESS_SHARED
attribute flag is used when creating a mutex and/or conditional variable.
Also introduces pthread_condattr_init/destroy/setpshared/getpshared.
Change-Id: I3a0e2116f467072b046524cb5babc00e41057a53
The problem was that the 'defdname' field of res_state structure
was not properly initialized in __res_vinit(). This field is used
to store the default domain name, which is normally build from
calling gethostname() (see line 549 of res_init.c).
Unfortunately, in the typical Android case, gethostname() returns
an error (the hostname is configured) and a random stack string is
used later to build the DNS search list (see lines 556+ in res_init.c)
For the sake of illustration, let's say the search list is set to
a random value like 'xWLK'.
The end result is that when trying to result an unknown domain name
(e.g. 'www.ptn'), the query fails then the resolver tries to make a
new query with the DNS search list path(s) appended (e.g. 'www.ptn.xWLK').
The patch simply initializes 'defdname' to an empty string to avoid
this when the net.dns.search system property is not set.
Also contains whitespace/formatting fixes
Java changes required not to mess up the ordering from bionic will arrive in a
later commit.) In particular, this will give us more correct behavior when on a
6to4 network, in that IPv4 will usually be preferred over 6to4.
Most of RFC 3484 is implemented -- what's not is rule 3 (avoid deprecated
addresses), 4 (prefer home addresses) and 7 (prefer native transport) as they
require low-level access to the kernel routing table via netlink. (glibc also
started out this way, and these rules are primarily useful in pretty obscure
circumstances, so we should be fine for the time being.)
Also, rule 9 (use longest matching prefix) has been modified so it does not try
to sort IPv4 addresses; given current IPv4 addressing practice these rules are
pretty much meaningless. Finally, I've added support for Teredo as a separate
label, with slightly lower preference than 6to4. (Vista puts the preference
below IPv4 by default. glibc puts the preference together with non-tunneled
IPv6.)
Note that this patch removes support for the "sortlist" directive in
resolv.conf; I've never seen it in actual use, it's irrelevant for Android
(since we don't use resolv.conf anyway), and it's not clear how it would be
implemented alongside RFC 3484.
Only provide an implementation for ARM at the moment, since
it requires specific assembly fragments (the standard syscall
stubs cannot be used because the child returns in a different
stack).