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
Previously, event_base.activequeues was of type "array of pointers to
eventlist." This was pointless: none of the eventlists were allowed
to be NULL. Worse, it was inefficient:
- It made looking up an active event queue take two pointer
deferences instead of one, thus risking extra cache misses.
- It used more RAM than it needed to, because of the extra pointer
and the malloc overhead.
Also, this patch fixes a bug where we were saying
calloc(N,N*sizeof(X)) instead of calloc(N,sizeof(X)) when allocating
activequeues. That part, I'll backport.
Also, we warn and return -1 on failure to allocate activequeues,
rather than calling event_err.
svn:r1525
Previously, if the user scheduled a persistent timeout for {1,0}, we
would schedule the first one at "now+one second", and then when we
were about to run its callback, we would schedule it again for one
second after that. This would introduce creeping delays to the event
that was supposed to run every second.
Now, we schedule the event for one second after it was _last
scheduled_. To do this, we introduce internal code to add an event at
an _absolute_ tv rather than at now+tv.
svn:r1520
Libevent's current timeout code is relatively optimized for the
randomly scattered timeout case, where events are added with their
timeouts in no particular order. We add and remove timeouts with
O(lg n) behavior.
Frequently, however, an application will want to have many timeouts
of the same value. For example, we might have 1000 bufferevents,
each with a 2 second timeout on reading or writing. If we knew this
were always the case, we could just put timeouts in a queue and get
O(1) add and remove behavior. Of course, a queue would give O(n)
performance for a scattered timeout pattern, so we don't want to
just switch the implementation.
This patch gives the user the ability to explicitly tag certain
timeout values as being "very common". These timeout values have a
cookie encoded in the high bits of their tv_usec field to indicate
which queue they belong on. The queues themselves are each
triggered by an entry in the minheap.
See the regress_main.c code for an example use.
svn:r1517
Yes, some people like to have a BSD-family kernel (thus getting
kqueue) with a GNU-family libc (thus occasionally mandating
_GNU_SOURCE).
Thanks to Debian for noticing this.
svn:r1514
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
Previously, each of the three make-an-event-base functions would exit
under different, weird circumstances, but return NULL on others.
- All three would exit on OOM sometimes.
- event_base_new() and event_init() would die if all backends were
disabled.
- None of them would die if the socketpair() call failed.
Now, only event_init() exits on failure, and it exits on every kind of
failure. event_base_new() and event_base_new_with_config() never do.
svn:r1472
This makes our interfaces usable from C++, which doesn't believe
you can say "bufferevent_socket_nase(base, -1,
BEV_OPT_CLOSE_ON_FREE|BEV_OPT_DEFER_CALLBACKS)" but which instead
would demand "static_cast<bufferevent_options>(BEV_OPT_CLOSE_ON_FREE|
BEV_OPT_DEFER_CALLBACKS))" for the last argument.
Diagnosis and patch from Chris Davis.
svn:r1456
Christopher Davis reported:
Connection failures aren't reported on Windows when
using bufferevent_socket_connect, because Windows uses
select's exceptfds to notify of failure, and libevent
treats them like read events. Only the write event
handler is currently used to handle connection events.
We should think hard about this one, since it changes
behavior from 1.4.x. Anything that worked on Mac/Unix before
will work more consistently on Windows now... but this might
break stuff that worked only on Windows, but nowhere else.
Patch from Chris Davis.
svn:r1454
This is harder than it sounds, since we need to make sure to
release the lock around the key call to the kernel (e.g.,
select, epoll_wait, kevent), AND we need to make sure that
none of the fields that are used in that call are touched by
anything that might be running concurrently in another
thread. I managed to do this pretty well for everything but
poll(). With poll, I needed to introduce a copy of the
event_set structure.
This patch also fixes a bug in win32.c where we called
realloc() instead of mm_realloc().
svn:r1450
We do this by not allocating the maximum epoll_event array for the epoll
backend at startup. Instead, we start out accepting 32 events at a time, and
double the array's size when it seems that the OS is generating events faster
than we're requesting them. This saves up to 374K per epoll-based
event_base. Resolves bug 2839240.
svn:r1428
Previously, if we had a socket bufferevent in connect state, we'd send
both of these to indicate that the connection was done. That was broken
since the point of adding BEV_EVENT_CONNECTED was so that we could
distinguish "we're connected" and "we wrote something".
Now, writecb is called only when
A) the connection finished but the user never put the socket into a
"connecting" state, or
B) data was actually written.
svn:r1425
We need to comb the rest of the code to make sure that we don't blindly wrap
functions in LOCK(x), UNLOCK(x) when those functions might contain a FREE(x)
in the middle.
Rocco Carbone found and reported this bug.
svn:r1384
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
They're now called evtag_encode_int(64). The old names are available
as macros in event2/tag_compat.h.
Also, add unit tests for encode/decode_int64.
svn:r1365
Previously, events that were disabled using EVENT_NO* were left out of
event_get_supported_methods(). This was wrong, broke unit tests
(under some circumstances) and left the user with no good way to tell
which methods were actually compiled in.
Fixes bug 2821015.
svn:r1344
This gives you the property that once you have called event_del(E),
you know that E is no longer running or pending or active at all, and
so it is safe to delete the resource used by E's callback.
svn:r1341
Patch from Zack Weinberg. His message:
This one eliminates all use of AC_CHECK_LIB in the configure script.
AC_CHECK_LIB has a serious flaw: if the library you mention *exists*
but is not *necessary* for the function you want, it adds it to
$(LIBS) anyway. This was fine in the days of static libraries,
because the linker would ignore an .a library that didn't contain
anything you needed. However, ELF shared libraries are different
(let's not get into why): the linker will by default record a
DT_NEEDED entry for every shared object mentioned on the link
command line. Thus, every use of AC_CHECK_LIB is a potential
unnecessary DT_NEEDED, making extra work for the dynamic loader. The
cure is simply to use AC_SEARCH_LIBS instead; it first tries to find
the function you ask for in libc, and only if that doesn't work does
it try to use the extra library you mention.
For the same reasons, pkg-config .pc files should distinguish
between the libraries to use for shared linkage (Libs:) and the
additional libraries needed for static linkage (Libs.private:). I
have also made that correction in this patch. I also took the
opportunity to clean up the substitution variables a little and make
absolutely sure that the core library does not get linked against
zlib.
svn:r1338
This fixes part of bug 2800642, I believe, though there is still a
general race condition in multithreaded use of events that we need to
think about.
svn:r1337
