Chris Davis reports that this is also necessary to fix building with
shared libraries on OSX for him. Should fix bug 2997775.
There is probably a better fix for the issues solved by commit
3cbca8661f, but for now, we're trying to get a beta out the door.
It turns out that commit 3cbca8661f broke building with shared
libraries on OSX. Since -no-undefined is only necessary on platforms
like win32, only use it there.
There may be a better fix for this. Should fix bug 2997775.
It would be great to have the manpages come back some time, perhaps
from a refactoring of my asciidoc book, but for now the existing
manpages were the single worst, most incomplete, and most misleading
libevent documentation we had. (Less misleading: the doxygen output,
the header files, and my reference book.)
If you tried to build with automake-1.6 or earlier, we would
previously spit out pages and pages of garbage output. Now, automake
should just say "Hey, I'm not new enough for this."
AC_LIBOBJ is really only meant for defining missing library functions,
not conditional code compilation. Sticking our conditionally compiled
modules in SYS_SRC should make stuff easier to maintain.
Previously, evdns was at the mercy of the user for providing a good
entropy source; without one, it would be vulnerable to various
active attacks.
This patch adds a port of OpenBSD's arc4random() calls to Libevent
[port by Chris Davis], and wraps it up a little bit so we can use it
more safely.
For what it's worth, we are aware that "Copyright $YEAR $NAME" is
sufficient notice of copyright on software under US law and
Internationally, and saying Copyright (c) $YEAR $NAME is a bit nutty.
The character sequence (c) has never been ruled to have the same force
in US law as the actual copyright symbol, and that neither of these
US-specific symbols adds anything of value beyond saying "Copyright"
since the Berne convention took effect in the US back in 1989.
Similarly, saying "all rights reserved" doesn't do anything magical
unless your software goes in a time-warp back to when the Buenos Aires
Convention was the general rule. (And what will they run it on back
then?) And what would even lead you to say "All Rights Reserved" when
you're explicitly granting most of those rights to anybody receiving
the work in accordance with the 3-clause BSD license?
But still the FOSS community retains these ritual notations out of a
kind of cargo-cult lawyering. Who knows? Perhaps one day, if we
write our copyright notices ineptly enough, John Frum will come and
give us a DFSG-compatible license that everybody can get behind.
(Also, I am not a lawyer. The above should not be taken as legal
advice. -- Nick)
This is necessary or useful for a few reasons:
1) Sometimes applications will add and delete the same event more
than once between calls to dispatch. Processing these changes
immediately is needless, and potentially expensive (especially
if we're on a system that makes one syscall per changed event).
Yes, this actually happens in practice for nonpathological
code, such as in cases where the user's callback conditionally
re-adds a non-persistent event, or where draining a buffer
turns off writing and invokes a user callback which adds more
data which in turn re-enabled writing.
2) Sometimes we can coalesce multiple changes on the same fd into
a single syscall if we know about them in advance. For
example, epoll can do an add and a delete at the same time, but
only if we have found out about both of them before we tell
epoll.
3) Sometimes adding an event that we immediately delete can cause
unintended consequences: in kqueue, this makes pending events
get reported spuriously.
The fairness algorithms are not the best, not every bufferevent type
is supported, and some of the locking tricks here are simply absurd.
Still, this code should be a good first step.
Previously, there was no good way to request different kinds of lock
(say, read/write vs writeonly or recursive vs nonrecursive), or for a
lock function to signal failure (which would be important for a
trylock mode).
This patch revises the lock API to be a bit more useful. The older
lock calls are still supported for now.
We also add a debugging mode to catch common errors in using the
locking APIs.
The entry points are evutil_getaddrinfo and evdns_getaddrinfo respectively.
There are fairly extensive unit tests.
I believe this code conforms to RFC3493 pretty closely, but there are
probably more issues. It should get tested on more platforms.
This code means we can dump the well-intentioned but weirdly-implemented
bufferevent_evdns and evutil_resolve code.
svn:r1537
This function, bufferevent_socket_connect_hostname() can either use
evdns to do the resolve, or use a new function (evutil_resolve) that
uses getaddrinfo or gethostbyname, like http.c does now.
This function is meant to eventually replace the hostname resolution mess in
http.c.
svn:r1496
I've gone through everything that it declared to see where it was used,
and it seems that we probably don't need it anywhere.
Here's what it declared, and why I think we're okay dropping it.
o struct timeval {}
(Used all over, and we can't really get away with declaring it ourselves;
we need the same definition the system uses. If we can't find struct
timeval, we're pretty much sunk.)
o struct timespec {}
(Used in event.c, evdns.c, kqueue.c, evport.c. Of these,
kqueue.c and event.c include sys/_time.h. event.c conditions its use on
_EVENT_HAVE_CLOCK_GETTIME, and kqueue() only works if timespec is defined.)
o TIMEVAL_TO_TIMESPEC
(Used in kqueue.c, but every place with kqueue has sys/time.h)
o struct timezone {}
(event2/util.h has a forward declaration; only evutil.c references it and
doesn't look at its contents.)
o timerclear, timerisset, timercmp, timeradd, timersub
(Everything now uses the evutil_timer* variants.)
o ITIMER_REAL, ITIMER_VIRTUAL, ITIMER_PROF, struct itemerval
(These are only used in test/regress.c, which does not include _time.h)
o CLOCK_REALTIME
(Only used in evdns.c, which does not include _time.h)
o TIMESPEC_TO_TIMEVAL
o DST_*
o timespecclear, timespecisset, timespeccmp, timespecadd, timespecsub
o struct clockinfo {}
o CLOCK_VIRTUAL, CLOCK_PROF
o TIMER_RELTIME, TIMER_ABSTIME
(unused)
svn:r1494
This code adds a new Bufferevent type that is only compiled when the
openssl library is present. It supports using an SSL object and an
event alert mechanism, which can either be an fd or an underlying
bufferevent.
There is still more work to do: the unit tests are incomplete, and we
need to support flush and shutdown much better. Sometimes events are
generated needlessly: this will hose performance.
There's a new encrypting proxy in sample/le-proxy.c.
This code has only been tested on OSX, and nowhere else.
svn:r1382
Patch from Zack Weinberg. His description:
This one might be a little more controversial. Libtool's -release and
-version-info options are supposed to be mutually exclusive, but it doesn't
either enforce that or make it sufficiently clear in the manual. Using
both makes the -version-info switch ineffective; you will get sonames like
"libevent-2.0.so.1", "libevent-2.1.so.1", etc., even though version 2.1
will presumably be backward ABI compatible with 2.0.
This patch just takes out the -release switches and bumps the -version-info
value to 2:0:0 so that people looking at the files in /usr/lib will not be
confused (it'll be "libevent.so.2"). This does change the soname, but the
current release is labeled an alpha, and it would be better to stop using
both switches as soon as possible, before someone over at libtool
headquarters decides to enforce the mutual exclusivity here...
Note that libevent_pthreads is not being linked with any versioning
switches I didn't change that because I wasn't sure whether it was
intentional.
svn:r1339
Either I need to make the callbacks get deferred in a base with no events (doable), or I need to make it okay to call launch_read from inside the callback for read (tricky).
svn:r1277
This is stuff that it's easy to get wrong (as I noticed when writing
bench_http), and that takes up a fair amount of space (see http.c).
Also, it's something that we'll eventually want to abstract to use
IOCP, where available.
svn:r1272
The new bufferevent_pair abstraction works like a set of buferevent_sockets
connected by a socketpair, except that it doesn't require a socketpair,
and therefore doesn't need to get the kernel involved.
It's also a good way to make sure that deferred callbacks work. It's a good
use case for deferred callbacks: before I implemented them, the recursive
relationship between the evbuffer callback and the read callback would
make the unit tests overflow the stack.
svn:r1152
