This patch adds a new compat_libevent.[ch] set of files, and moves our
Libevent compatibility and utilitity functions there. We build them
into a separate .a so that nothing else in src/commmon depends on
Libevent (partially fixing bug 507).
Also, do not use our own built-in evdns copy when we have Libevent
2.0, whose evdns is finally good enough (thus fixing Bug 920).
Really, our idiocy was that we were calling event_set() on the same
event more than once, which sometimes led to us calling event_set() on
an event that was already inserted, thus making it look uninserted.
With this patch, we just initialize the timeout events when we create
the requests and nameservers, and we don't need to worry about
double-add and double-del cases at all.
If we ever add an event, then set it, then add it again, there will be
now two pointers to the event in the event base. If we delete one and
free it, the first pointer will still be there, and possibly cause a
crash later.
This patch adds detection for this case to the code paths in
eventdns.c, and works around it. If the warning message ever
displays, then a cleverer fix is in order.
{I am not too confident that this *is* the fix, since bug 957 is very
tricky. If it is, it is a bugfix on 0.2.0.}
This resolves bug 526, wherein we would crash if the following
events occurred in this order:
A: We're an OR, and one of our nameservers goes down.
B: We launch a probe to it to see if it's up again. (We do this hourly
in steady-state.)
C: Before the probe finishes, we reconfigure our nameservers,
usually because we got a SIGHUP and the resolve.conf file changed.
D: The probe reply comes back, or times out. (There is a five-second
window for this, after B has happens).
IOW, if one of our nameservers is down and our nameserver
configuration has changed, there were 5 seconds per hour where HUPing
the server was unsafe.
Bugfix on 0.1.2.1-alpha. Too obscure to backport.
svn:r18306
The subversion $Id$ fields made every commit force a rebuild of
whatever file got committed. They were not actually useful for
telling the version of Tor files in the wild.
svn:r17867
Make dns resolver code more robust: handle nameservers with IPv6 addresses, make sure names in replies match requested names, make sure origin address of reply matches the address we asked.
svn:r16621
Fix all but 2 DOCDOC items; defer many XXX020s (particularly those where fixing them would fix no bugs at the risk of introducing some bugs).
svn:r13529
Fix some warnings identified by building with -D_FORTIFY_SOURCE=2. Remove a redundant (and nuts) definition of _FORTIFY_SOURCE from eventdns.c.
svn:r13424
Carry a new evdns function over from libevent: do not rely on compile-time code to set the transaction ID correctly. This will be important when we finally drop our internal copy of eventdns.c
svn:r11517
