+# This library is free software; you can redistribute it and/or modify
+# it under the same terms as Perl itself.
+#
+# This license differs from the rest of public-inbox
+#
+# This is a fork of the (for now) unmaintained Danga::Socket 1.61.
+# Unused features will be removed, and updates will be made to take
+# advantage of newer kernels
+
+package PublicInbox::DS;
+use strict;
+use bytes;
+use POSIX ();
+use Time::HiRes ();
+
+my $opt_bsd_resource = eval "use BSD::Resource; 1;";
+
+use vars qw{$VERSION};
+$VERSION = "1.61";
+
+use warnings;
+no warnings qw(deprecated);
+
+use PublicInbox::Syscall qw(:epoll);
+
+use fields ('sock', # underlying socket
+ 'fd', # numeric file descriptor
+ 'write_buf', # arrayref of scalars, scalarrefs, or coderefs to write
+ 'write_buf_offset', # offset into first array of write_buf to start writing at
+ 'write_buf_size', # total length of data in all write_buf items
+ 'write_set_watch', # bool: true if we internally set watch_write rather than by a subclass
+ 'read_push_back', # arrayref of "pushed-back" read data the application didn't want
+ 'closed', # bool: socket is closed
+ 'corked', # bool: socket is corked
+ 'event_watch', # bitmask of events the client is interested in (POLLIN,OUT,etc.)
+ 'peer_v6', # bool: cached; if peer is an IPv6 address
+ 'peer_ip', # cached stringified IP address of $sock
+ 'peer_port', # cached port number of $sock
+ 'local_ip', # cached stringified IP address of local end of $sock
+ 'local_port', # cached port number of local end of $sock
+ 'writer_func', # subref which does writing. must return bytes written (or undef) and set $! on errors
+ );
+
+use Errno qw(EINPROGRESS EWOULDBLOCK EISCONN ENOTSOCK
+ EPIPE EAGAIN EBADF ECONNRESET ENOPROTOOPT);
+use Socket qw(IPPROTO_TCP);
+use Carp qw(croak confess);
+
+use constant TCP_CORK => ($^O eq "linux" ? 3 : 0); # FIXME: not hard-coded (Linux-specific too)
+use constant DebugLevel => 0;
+
+use constant POLLIN => 1;
+use constant POLLOUT => 4;
+use constant POLLERR => 8;
+use constant POLLHUP => 16;
+use constant POLLNVAL => 32;
+
+our $HAVE_KQUEUE = eval { require IO::KQueue; 1 };
+
+our (
+ $HaveEpoll, # Flag -- is epoll available? initially undefined.
+ $HaveKQueue,
+ %DescriptorMap, # fd (num) -> PublicInbox::DS object
+ %PushBackSet, # fd (num) -> PublicInbox::DS (fds with pushed back read data)
+ $Epoll, # Global epoll fd (for epoll mode only)
+ $KQueue, # Global kqueue fd (for kqueue mode only)
+ @ToClose, # sockets to close when event loop is done
+ %OtherFds, # A hash of "other" (non-PublicInbox::DS) file
+ # descriptors for the event loop to track.
+
+ $PostLoopCallback, # subref to call at the end of each loop, if defined (global)
+ %PLCMap, # fd (num) -> PostLoopCallback (per-object)
+
+ $LoopTimeout, # timeout of event loop in milliseconds
+ $DoProfile, # if on, enable profiling
+ %Profiling, # what => [ utime, stime, calls ]
+ $DoneInit, # if we've done the one-time module init yet
+ @Timers, # timers
+ );
+
+Reset();
+
+#####################################################################
+### C L A S S M E T H O D S
+#####################################################################
+
+=head2 C<< CLASS->Reset() >>
+
+Reset all state
+
+=cut
+sub Reset {
+ %DescriptorMap = ();
+ %PushBackSet = ();
+ @ToClose = ();
+ %OtherFds = ();
+ $LoopTimeout = -1; # no timeout by default
+ $DoProfile = 0;
+ %Profiling = ();
+ @Timers = ();
+
+ $PostLoopCallback = undef;
+ %PLCMap = ();
+ $DoneInit = 0;
+
+ POSIX::close($Epoll) if defined $Epoll && $Epoll >= 0;
+ POSIX::close($KQueue) if defined $KQueue && $KQueue >= 0;
+
+ *EventLoop = *FirstTimeEventLoop;
+}
+
+=head2 C<< CLASS->HaveEpoll() >>
+
+Returns a true value if this class will use IO::Epoll for async IO.
+
+=cut
+sub HaveEpoll {
+ _InitPoller();
+ return $HaveEpoll;
+}
+
+=head2 C<< CLASS->WatchedSockets() >>
+
+Returns the number of file descriptors which are registered with the global
+poll object.
+
+=cut
+sub WatchedSockets {
+ return scalar keys %DescriptorMap;
+}
+*watched_sockets = *WatchedSockets;
+
+=head2 C<< CLASS->EnableProfiling() >>
+
+Turns profiling on, clearing current profiling data.
+
+=cut
+sub EnableProfiling {
+ if ($opt_bsd_resource) {
+ %Profiling = ();
+ $DoProfile = 1;
+ return 1;
+ }
+ return 0;
+}
+
+=head2 C<< CLASS->DisableProfiling() >>
+
+Turns off profiling, but retains data up to this point
+
+=cut
+sub DisableProfiling {
+ $DoProfile = 0;
+}
+
+=head2 C<< CLASS->ProfilingData() >>
+
+Returns reference to a hash of data in format:
+
+ ITEM => [ utime, stime, #calls ]
+
+=cut
+sub ProfilingData {
+ return \%Profiling;
+}
+
+=head2 C<< CLASS->ToClose() >>
+
+Return the list of sockets that are awaiting close() at the end of the
+current event loop.
+
+=cut
+sub ToClose { return @ToClose; }
+
+=head2 C<< CLASS->OtherFds( [%fdmap] ) >>
+
+Get/set the hash of file descriptors that need processing in parallel with
+the registered PublicInbox::DS objects.
+
+=cut
+sub OtherFds {
+ my $class = shift;
+ if ( @_ ) { %OtherFds = @_ }
+ return wantarray ? %OtherFds : \%OtherFds;
+}
+
+=head2 C<< CLASS->AddOtherFds( [%fdmap] ) >>
+
+Add fds to the OtherFds hash for processing.
+
+=cut
+sub AddOtherFds {
+ my $class = shift;
+ %OtherFds = ( %OtherFds, @_ ); # FIXME investigate what happens on dupe fds
+ return wantarray ? %OtherFds : \%OtherFds;
+}
+
+=head2 C<< CLASS->SetLoopTimeout( $timeout ) >>
+
+Set the loop timeout for the event loop to some value in milliseconds.
+
+A timeout of 0 (zero) means poll forever. A timeout of -1 means poll and return
+immediately.
+
+=cut
+sub SetLoopTimeout {
+ return $LoopTimeout = $_[1] + 0;
+}
+
+=head2 C<< CLASS->DebugMsg( $format, @args ) >>
+
+Print the debugging message specified by the C<sprintf>-style I<format> and
+I<args>
+
+=cut
+sub DebugMsg {
+ my ( $class, $fmt, @args ) = @_;
+ chomp $fmt;
+ printf STDERR ">>> $fmt\n", @args;
+}
+
+=head2 C<< CLASS->AddTimer( $seconds, $coderef ) >>
+
+Add a timer to occur $seconds from now. $seconds may be fractional, but timers
+are not guaranteed to fire at the exact time you ask for.
+
+Returns a timer object which you can call C<< $timer->cancel >> on if you need to.
+
+=cut
+sub AddTimer {
+ my $class = shift;
+ my ($secs, $coderef) = @_;
+
+ my $fire_time = Time::HiRes::time() + $secs;
+
+ my $timer = bless [$fire_time, $coderef], "PublicInbox::DS::Timer";
+
+ if (!@Timers || $fire_time >= $Timers[-1][0]) {
+ push @Timers, $timer;
+ return $timer;
+ }
+
+ # Now, where do we insert? (NOTE: this appears slow, algorithm-wise,
+ # but it was compared against calendar queues, heaps, naive push/sort,
+ # and a bunch of other versions, and found to be fastest with a large
+ # variety of datasets.)
+ for (my $i = 0; $i < @Timers; $i++) {
+ if ($Timers[$i][0] > $fire_time) {
+ splice(@Timers, $i, 0, $timer);
+ return $timer;
+ }
+ }
+
+ die "Shouldn't get here.";
+}
+
+=head2 C<< CLASS->DescriptorMap() >>
+
+Get the hash of PublicInbox::DS objects keyed by the file descriptor (fileno) they
+are wrapping.
+
+Returns a hash in list context or a hashref in scalar context.
+
+=cut
+sub DescriptorMap {
+ return wantarray ? %DescriptorMap : \%DescriptorMap;
+}
+*descriptor_map = *DescriptorMap;
+*get_sock_ref = *DescriptorMap;
+
+sub _InitPoller
+{
+ return if $DoneInit;
+ $DoneInit = 1;
+
+ if ($HAVE_KQUEUE) {
+ $KQueue = IO::KQueue->new();
+ $HaveKQueue = $KQueue >= 0;
+ if ($HaveKQueue) {
+ *EventLoop = *KQueueEventLoop;
+ }
+ }
+ elsif (PublicInbox::Syscall::epoll_defined()) {
+ $Epoll = eval { epoll_create(1024); };
+ $HaveEpoll = defined $Epoll && $Epoll >= 0;
+ if ($HaveEpoll) {
+ *EventLoop = *EpollEventLoop;
+ }
+ }
+
+ if (!$HaveEpoll && !$HaveKQueue) {
+ require IO::Poll;
+ *EventLoop = *PollEventLoop;
+ }
+}
+
+=head2 C<< CLASS->EventLoop() >>
+
+Start processing IO events. In most daemon programs this never exits. See
+C<PostLoopCallback> below for how to exit the loop.
+
+=cut
+sub FirstTimeEventLoop {
+ my $class = shift;
+
+ _InitPoller();
+
+ if ($HaveEpoll) {
+ EpollEventLoop($class);
+ } elsif ($HaveKQueue) {
+ KQueueEventLoop($class);
+ } else {
+ PollEventLoop($class);
+ }
+}
+
+## profiling-related data/functions
+our ($Prof_utime0, $Prof_stime0);
+sub _pre_profile {
+ ($Prof_utime0, $Prof_stime0) = getrusage();
+}
+
+sub _post_profile {
+ # get post information
+ my ($autime, $astime) = getrusage();
+
+ # calculate differences
+ my $utime = $autime - $Prof_utime0;
+ my $stime = $astime - $Prof_stime0;
+
+ foreach my $k (@_) {
+ $Profiling{$k} ||= [ 0.0, 0.0, 0 ];
+ $Profiling{$k}->[0] += $utime;
+ $Profiling{$k}->[1] += $stime;
+ $Profiling{$k}->[2]++;
+ }
+}
+
+# runs timers and returns milliseconds for next one, or next event loop
+sub RunTimers {
+ return $LoopTimeout unless @Timers;
+
+ my $now = Time::HiRes::time();
+
+ # Run expired timers
+ while (@Timers && $Timers[0][0] <= $now) {
+ my $to_run = shift(@Timers);
+ $to_run->[1]->($now) if $to_run->[1];
+ }
+
+ return $LoopTimeout unless @Timers;
+
+ # convert time to an even number of milliseconds, adding 1
+ # extra, otherwise floating point fun can occur and we'll
+ # call RunTimers like 20-30 times, each returning a timeout
+ # of 0.0000212 seconds
+ my $timeout = int(($Timers[0][0] - $now) * 1000) + 1;
+
+ # -1 is an infinite timeout, so prefer a real timeout
+ return $timeout if $LoopTimeout == -1;
+
+ # otherwise pick the lower of our regular timeout and time until
+ # the next timer
+ return $LoopTimeout if $LoopTimeout < $timeout;
+ return $timeout;
+}
+
+### The epoll-based event loop. Gets installed as EventLoop if IO::Epoll loads
+### okay.
+sub EpollEventLoop {
+ my $class = shift;
+
+ foreach my $fd ( keys %OtherFds ) {
+ if (epoll_ctl($Epoll, EPOLL_CTL_ADD, $fd, EPOLLIN) == -1) {
+ warn "epoll_ctl(): failure adding fd=$fd; $! (", $!+0, ")\n";
+ }
+ }
+
+ while (1) {
+ my @events;
+ my $i;
+ my $timeout = RunTimers();
+
+ # get up to 1000 events
+ my $evcount = epoll_wait($Epoll, 1000, $timeout, \@events);
+ EVENT:
+ for ($i=0; $i<$evcount; $i++) {
+ my $ev = $events[$i];
+
+ # it's possible epoll_wait returned many events, including some at the end
+ # that ones in the front triggered unregister-interest actions. if we
+ # can't find the %sock entry, it's because we're no longer interested
+ # in that event.
+ my PublicInbox::DS $pob = $DescriptorMap{$ev->[0]};
+ my $code;
+ my $state = $ev->[1];
+
+ # if we didn't find a Perlbal::Socket subclass for that fd, try other
+ # pseudo-registered (above) fds.
+ if (! $pob) {
+ if (my $code = $OtherFds{$ev->[0]}) {
+ $code->($state);
+ } else {
+ my $fd = $ev->[0];
+ warn "epoll() returned fd $fd w/ state $state for which we have no mapping. removing.\n";
+ POSIX::close($fd);
+ epoll_ctl($Epoll, EPOLL_CTL_DEL, $fd, 0);
+ }
+ next;
+ }
+
+ DebugLevel >= 1 && $class->DebugMsg("Event: fd=%d (%s), state=%d \@ %s\n",
+ $ev->[0], ref($pob), $ev->[1], time);
+
+ if ($DoProfile) {
+ my $class = ref $pob;
+
+ # call profiling action on things that need to be done
+ if ($state & EPOLLIN && ! $pob->{closed}) {
+ _pre_profile();
+ $pob->event_read;
+ _post_profile("$class-read");
+ }
+
+ if ($state & EPOLLOUT && ! $pob->{closed}) {
+ _pre_profile();
+ $pob->event_write;
+ _post_profile("$class-write");
+ }
+
+ if ($state & (EPOLLERR|EPOLLHUP)) {
+ if ($state & EPOLLERR && ! $pob->{closed}) {
+ _pre_profile();
+ $pob->event_err;
+ _post_profile("$class-err");
+ }
+ if ($state & EPOLLHUP && ! $pob->{closed}) {
+ _pre_profile();
+ $pob->event_hup;
+ _post_profile("$class-hup");
+ }
+ }
+
+ next;
+ }
+
+ # standard non-profiling codepat
+ $pob->event_read if $state & EPOLLIN && ! $pob->{closed};
+ $pob->event_write if $state & EPOLLOUT && ! $pob->{closed};
+ if ($state & (EPOLLERR|EPOLLHUP)) {
+ $pob->event_err if $state & EPOLLERR && ! $pob->{closed};
+ $pob->event_hup if $state & EPOLLHUP && ! $pob->{closed};
+ }
+ }
+ return unless PostEventLoop();
+ }
+ exit 0;
+}
+
+### The fallback IO::Poll-based event loop. Gets installed as EventLoop if
+### IO::Epoll fails to load.
+sub PollEventLoop {
+ my $class = shift;
+
+ my PublicInbox::DS $pob;
+
+ while (1) {
+ my $timeout = RunTimers();
+
+ # the following sets up @poll as a series of ($poll,$event_mask)
+ # items, then uses IO::Poll::_poll, implemented in XS, which
+ # modifies the array in place with the even elements being
+ # replaced with the event masks that occured.
+ my @poll;
+ foreach my $fd ( keys %OtherFds ) {
+ push @poll, $fd, POLLIN;
+ }
+ while ( my ($fd, $sock) = each %DescriptorMap ) {
+ push @poll, $fd, $sock->{event_watch};
+ }
+
+ # if nothing to poll, either end immediately (if no timeout)
+ # or just keep calling the callback
+ unless (@poll) {
+ select undef, undef, undef, ($timeout / 1000);
+ return unless PostEventLoop();
+ next;
+ }
+
+ my $count = IO::Poll::_poll($timeout, @poll);
+ unless ($count) {
+ return unless PostEventLoop();
+ next;
+ }
+
+ # Fetch handles with read events
+ while (@poll) {
+ my ($fd, $state) = splice(@poll, 0, 2);
+ next unless $state;
+
+ $pob = $DescriptorMap{$fd};
+
+ if (!$pob) {
+ if (my $code = $OtherFds{$fd}) {
+ $code->($state);
+ }
+ next;
+ }
+
+ $pob->event_read if $state & POLLIN && ! $pob->{closed};
+ $pob->event_write if $state & POLLOUT && ! $pob->{closed};
+ $pob->event_err if $state & POLLERR && ! $pob->{closed};
+ $pob->event_hup if $state & POLLHUP && ! $pob->{closed};
+ }
+
+ return unless PostEventLoop();
+ }
+
+ exit 0;
+}
+
+### The kqueue-based event loop. Gets installed as EventLoop if IO::KQueue works
+### okay.
+sub KQueueEventLoop {
+ my $class = shift;
+
+ foreach my $fd (keys %OtherFds) {
+ $KQueue->EV_SET($fd, IO::KQueue::EVFILT_READ(), IO::KQueue::EV_ADD());
+ }
+
+ while (1) {
+ my $timeout = RunTimers();
+ my @ret = $KQueue->kevent($timeout);
+
+ foreach my $kev (@ret) {
+ my ($fd, $filter, $flags, $fflags) = @$kev;
+ my PublicInbox::DS $pob = $DescriptorMap{$fd};
+ if (!$pob) {
+ if (my $code = $OtherFds{$fd}) {
+ $code->($filter);
+ } else {
+ warn "kevent() returned fd $fd for which we have no mapping. removing.\n";
+ POSIX::close($fd); # close deletes the kevent entry
+ }
+ next;
+ }
+
+ DebugLevel >= 1 && $class->DebugMsg("Event: fd=%d (%s), flags=%d \@ %s\n",
+ $fd, ref($pob), $flags, time);
+
+ $pob->event_read if $filter == IO::KQueue::EVFILT_READ() && !$pob->{closed};
+ $pob->event_write if $filter == IO::KQueue::EVFILT_WRITE() && !$pob->{closed};
+ if ($flags == IO::KQueue::EV_EOF() && !$pob->{closed}) {
+ if ($fflags) {
+ $pob->event_err;
+ } else {
+ $pob->event_hup;
+ }
+ }
+ }
+ return unless PostEventLoop();
+ }
+
+ exit(0);
+}
+
+=head2 C<< CLASS->SetPostLoopCallback( CODEREF ) >>
+
+Sets post loop callback function. Pass a subref and it will be
+called every time the event loop finishes.
+
+Return 1 (or any true value) from the sub to make the loop continue, 0 or false
+and it will exit.
+
+The callback function will be passed two parameters: \%DescriptorMap, \%OtherFds.
+
+=cut
+sub SetPostLoopCallback {
+ my ($class, $ref) = @_;
+
+ if (ref $class) {
+ # per-object callback
+ my PublicInbox::DS $self = $class;
+ if (defined $ref && ref $ref eq 'CODE') {
+ $PLCMap{$self->{fd}} = $ref;
+ } else {
+ delete $PLCMap{$self->{fd}};
+ }
+ } else {
+ # global callback
+ $PostLoopCallback = (defined $ref && ref $ref eq 'CODE') ? $ref : undef;
+ }
+}
+
+# Internal function: run the post-event callback, send read events
+# for pushed-back data, and close pending connections. returns 1
+# if event loop should continue, or 0 to shut it all down.
+sub PostEventLoop {
+ # fire read events for objects with pushed-back read data
+ my $loop = 1;
+ while ($loop) {
+ $loop = 0;
+ foreach my $fd (keys %PushBackSet) {
+ my PublicInbox::DS $pob = $PushBackSet{$fd};
+
+ # a previous event_read invocation could've closed a
+ # connection that we already evaluated in "keys
+ # %PushBackSet", so skip ones that seem to have
+ # disappeared. this is expected.
+ next unless $pob;
+
+ die "ASSERT: the $pob socket has no read_push_back" unless @{$pob->{read_push_back}};
+ next unless (! $pob->{closed} &&
+ $pob->{event_watch} & POLLIN);
+ $loop = 1;
+ $pob->event_read;
+ }
+ }
+
+ # now we can close sockets that wanted to close during our event processing.
+ # (we didn't want to close them during the loop, as we didn't want fd numbers
+ # being reused and confused during the event loop)
+ while (my $sock = shift @ToClose) {
+ my $fd = fileno($sock);
+
+ # close the socket. (not a PublicInbox::DS close)
+ $sock->close;
+
+ # and now we can finally remove the fd from the map. see
+ # comment above in _cleanup.
+ delete $DescriptorMap{$fd};
+ }
+
+
+ # by default we keep running, unless a postloop callback (either per-object
+ # or global) cancels it
+ my $keep_running = 1;
+
+ # per-object post-loop-callbacks
+ for my $plc (values %PLCMap) {
+ $keep_running &&= $plc->(\%DescriptorMap, \%OtherFds);
+ }
+
+ # now we're at the very end, call callback if defined
+ if (defined $PostLoopCallback) {
+ $keep_running &&= $PostLoopCallback->(\%DescriptorMap, \%OtherFds);
+ }
+
+ return $keep_running;
+}
+
+#####################################################################
+### PublicInbox::DS-the-object code
+#####################################################################
+
+=head2 OBJECT METHODS
+
+=head2 C<< CLASS->new( $socket ) >>
+
+Create a new PublicInbox::DS subclass object for the given I<socket> which will
+react to events on it during the C<EventLoop>.
+
+This is normally (always?) called from your subclass via:
+
+ $class->SUPER::new($socket);
+
+=cut
+sub new {
+ my PublicInbox::DS $self = shift;
+ $self = fields::new($self) unless ref $self;
+
+ my $sock = shift;
+
+ $self->{sock} = $sock;
+ my $fd = fileno($sock);
+
+ Carp::cluck("undef sock and/or fd in PublicInbox::DS->new. sock=" . ($sock || "") . ", fd=" . ($fd || ""))
+ unless $sock && $fd;
+
+ $self->{fd} = $fd;
+ $self->{write_buf} = [];
+ $self->{write_buf_offset} = 0;
+ $self->{write_buf_size} = 0;
+ $self->{closed} = 0;
+ $self->{corked} = 0;
+ $self->{read_push_back} = [];
+
+ $self->{event_watch} = POLLERR|POLLHUP|POLLNVAL;
+
+ _InitPoller();
+
+ if ($HaveEpoll) {
+ epoll_ctl($Epoll, EPOLL_CTL_ADD, $fd, $self->{event_watch})
+ and die "couldn't add epoll watch for $fd\n";
+ }
+ elsif ($HaveKQueue) {
+ # Add them to the queue but disabled for now
+ $KQueue->EV_SET($fd, IO::KQueue::EVFILT_READ(),
+ IO::KQueue::EV_ADD() | IO::KQueue::EV_DISABLE());
+ $KQueue->EV_SET($fd, IO::KQueue::EVFILT_WRITE(),
+ IO::KQueue::EV_ADD() | IO::KQueue::EV_DISABLE());
+ }
+
+ Carp::cluck("PublicInbox::DS::new blowing away existing descriptor map for fd=$fd ($DescriptorMap{$fd})")
+ if $DescriptorMap{$fd};
+
+ $DescriptorMap{$fd} = $self;
+ return $self;
+}
+
+
+#####################################################################
+### I N S T A N C E M E T H O D S
+#####################################################################
+
+=head2 C<< $obj->tcp_cork( $boolean ) >>
+
+Turn TCP_CORK on or off depending on the value of I<boolean>.
+
+=cut
+sub tcp_cork {
+ my PublicInbox::DS $self = $_[0];
+ my $val = $_[1];
+
+ # make sure we have a socket
+ return unless $self->{sock};
+ return if $val == $self->{corked};
+
+ my $rv;
+ if (TCP_CORK) {
+ $rv = setsockopt($self->{sock}, IPPROTO_TCP, TCP_CORK,
+ pack("l", $val ? 1 : 0));
+ } else {
+ # FIXME: implement freebsd *PUSH sockopts
+ $rv = 1;
+ }
+
+ # if we failed, close (if we're not already) and warn about the error
+ if ($rv) {
+ $self->{corked} = $val;
+ } else {
+ if ($! == EBADF || $! == ENOTSOCK) {
+ # internal state is probably corrupted; warn and then close if
+ # we're not closed already
+ warn "setsockopt: $!";
+ $self->close('tcp_cork_failed');
+ } elsif ($! == ENOPROTOOPT || $!{ENOTSOCK} || $!{EOPNOTSUPP}) {
+ # TCP implementation doesn't support corking, so just ignore it
+ # or we're trying to tcp-cork a non-socket (like a socketpair pipe
+ # which is acting like a socket, which Perlbal does for child
+ # processes acting like inetd-like web servers)
+ } else {
+ # some other error; we should never hit here, but if we do, die
+ die "setsockopt: $!";
+ }
+ }
+}
+
+=head2 C<< $obj->steal_socket() >>
+
+Basically returns our socket and makes it so that we don't try to close it,
+but we do remove it from epoll handlers. THIS CLOSES $self. It is the same
+thing as calling close, except it gives you the socket to use.
+
+=cut
+sub steal_socket {
+ my PublicInbox::DS $self = $_[0];
+ return if $self->{closed};
+
+ # cleanup does most of the work of closing this socket
+ $self->_cleanup();
+
+ # now undef our internal sock and fd structures so we don't use them
+ my $sock = $self->{sock};
+ $self->{sock} = undef;
+ return $sock;
+}
+
+=head2 C<< $obj->close( [$reason] ) >>
+
+Close the socket. The I<reason> argument will be used in debugging messages.
+
+=cut
+sub close {
+ my PublicInbox::DS $self = $_[0];
+ return if $self->{closed};
+
+ # print out debugging info for this close
+ if (DebugLevel) {
+ my ($pkg, $filename, $line) = caller;
+ my $reason = $_[1] || "";
+ warn "Closing \#$self->{fd} due to $pkg/$filename/$line ($reason)\n";
+ }
+
+ # this does most of the work of closing us
+ $self->_cleanup();
+
+ # defer closing the actual socket until the event loop is done
+ # processing this round of events. (otherwise we might reuse fds)
+ if ($self->{sock}) {
+ push @ToClose, $self->{sock};
+ $self->{sock} = undef;
+ }
+
+ return 0;
+}
+
+### METHOD: _cleanup()
+### Called by our closers so we can clean internal data structures.
+sub _cleanup {
+ my PublicInbox::DS $self = $_[0];
+
+ # we're effectively closed; we have no fd and sock when we leave here
+ $self->{closed} = 1;
+
+ # we need to flush our write buffer, as there may
+ # be self-referential closures (sub { $client->close })
+ # preventing the object from being destroyed
+ $self->{write_buf} = [];
+
+ # uncork so any final data gets sent. only matters if the person closing
+ # us forgot to do it, but we do it to be safe.
+ $self->tcp_cork(0);
+
+ # if we're using epoll, we have to remove this from our epoll fd so we stop getting
+ # notifications about it
+ if ($HaveEpoll && $self->{fd}) {
+ if (epoll_ctl($Epoll, EPOLL_CTL_DEL, $self->{fd}, $self->{event_watch}) != 0) {
+ # dump_error prints a backtrace so we can try to figure out why this happened
+ $self->dump_error("epoll_ctl(): failure deleting fd=$self->{fd} during _cleanup(); $! (" . ($!+0) . ")");
+ }
+ }
+
+ # now delete from mappings. this fd no longer belongs to us, so we don't want
+ # to get alerts for it if it becomes writable/readable/etc.
+ delete $PushBackSet{$self->{fd}};
+ delete $PLCMap{$self->{fd}};
+
+ # we explicitly don't delete from DescriptorMap here until we
+ # actually close the socket, as we might be in the middle of
+ # processing an epoll_wait/etc that returned hundreds of fds, one
+ # of which is not yet processed and is what we're closing. if we
+ # keep it in DescriptorMap, then the event harnesses can just
+ # looked at $pob->{closed} and ignore it. but if it's an
+ # un-accounted for fd, then it (understandably) freak out a bit
+ # and emit warnings, thinking their state got off.
+
+ # and finally get rid of our fd so we can't use it anywhere else
+ $self->{fd} = undef;
+}
+
+=head2 C<< $obj->sock() >>
+
+Returns the underlying IO::Handle for the object.
+
+=cut
+sub sock {
+ my PublicInbox::DS $self = shift;
+ return $self->{sock};
+}
+
+=head2 C<< $obj->set_writer_func( CODEREF ) >>
+
+Sets a function to use instead of C<syswrite()> when writing data to the socket.
+
+=cut
+sub set_writer_func {
+ my PublicInbox::DS $self = shift;
+ my $wtr = shift;
+ Carp::croak("Not a subref") unless !defined $wtr || UNIVERSAL::isa($wtr, "CODE");
+ $self->{writer_func} = $wtr;
+}
+
+=head2 C<< $obj->write( $data ) >>
+
+Write the specified data to the underlying handle. I<data> may be scalar,
+scalar ref, code ref (to run when there), or undef just to kick-start.
+Returns 1 if writes all went through, or 0 if there are writes in queue. If
+it returns 1, caller should stop waiting for 'writable' events)
+
+=cut
+sub write {
+ my PublicInbox::DS $self;
+ my $data;
+ ($self, $data) = @_;
+
+ # nobody should be writing to closed sockets, but caller code can
+ # do two writes within an event, have the first fail and
+ # disconnect the other side (whose destructor then closes the
+ # calling object, but it's still in a method), and then the
+ # now-dead object does its second write. that is this case. we
+ # just lie and say it worked. it'll be dead soon and won't be
+ # hurt by this lie.
+ return 1 if $self->{closed};
+
+ my $bref;
+
+ # just queue data if there's already a wait
+ my $need_queue;
+
+ if (defined $data) {
+ $bref = ref $data ? $data : \$data;
+ if ($self->{write_buf_size}) {
+ push @{$self->{write_buf}}, $bref;
+ $self->{write_buf_size} += ref $bref eq "SCALAR" ? length($$bref) : 1;
+ return 0;
+ }
+
+ # this flag says we're bypassing the queue system, knowing we're the
+ # only outstanding write, and hoping we don't ever need to use it.
+ # if so later, though, we'll need to queue
+ $need_queue = 1;
+ }
+
+ WRITE:
+ while (1) {
+ return 1 unless $bref ||= $self->{write_buf}[0];
+
+ my $len;
+ eval {
+ $len = length($$bref); # this will die if $bref is a code ref, caught below
+ };
+ if ($@) {
+ if (UNIVERSAL::isa($bref, "CODE")) {
+ unless ($need_queue) {
+ $self->{write_buf_size}--; # code refs are worth 1
+ shift @{$self->{write_buf}};
+ }
+ $bref->();
+
+ # code refs are just run and never get reenqueued
+ # (they're one-shot), so turn off the flag indicating the
+ # outstanding data needs queueing.
+ $need_queue = 0;
+
+ undef $bref;
+ next WRITE;
+ }
+ die "Write error: $@ <$bref>";
+ }
+
+ my $to_write = $len - $self->{write_buf_offset};
+ my $written;
+ if (my $wtr = $self->{writer_func}) {
+ $written = $wtr->($bref, $to_write, $self->{write_buf_offset});
+ } else {
+ $written = syswrite($self->{sock}, $$bref, $to_write, $self->{write_buf_offset});
+ }
+
+ if (! defined $written) {
+ if ($! == EPIPE) {
+ return $self->close("EPIPE");
+ } elsif ($! == EAGAIN) {
+ # since connection has stuff to write, it should now be
+ # interested in pending writes:
+ if ($need_queue) {
+ push @{$self->{write_buf}}, $bref;
+ $self->{write_buf_size} += $len;
+ }
+ $self->{write_set_watch} = 1 unless $self->{event_watch} & POLLOUT;
+ $self->watch_write(1);
+ return 0;
+ } elsif ($! == ECONNRESET) {
+ return $self->close("ECONNRESET");
+ }
+
+ DebugLevel >= 1 && $self->debugmsg("Closing connection ($self) due to write error: $!\n");
+
+ return $self->close("write_error");
+ } elsif ($written != $to_write) {
+ DebugLevel >= 2 && $self->debugmsg("Wrote PARTIAL %d bytes to %d",
+ $written, $self->{fd});
+ if ($need_queue) {
+ push @{$self->{write_buf}}, $bref;
+ $self->{write_buf_size} += $len;
+ }
+ # since connection has stuff to write, it should now be
+ # interested in pending writes:
+ $self->{write_buf_offset} += $written;
+ $self->{write_buf_size} -= $written;
+ $self->on_incomplete_write;
+ return 0;
+ } elsif ($written == $to_write) {
+ DebugLevel >= 2 && $self->debugmsg("Wrote ALL %d bytes to %d (nq=%d)",
+ $written, $self->{fd}, $need_queue);
+ $self->{write_buf_offset} = 0;
+
+ if ($self->{write_set_watch}) {
+ $self->watch_write(0);
+ $self->{write_set_watch} = 0;
+ }
+
+ # this was our only write, so we can return immediately
+ # since we avoided incrementing the buffer size or
+ # putting it in the buffer. we also know there
+ # can't be anything else to write.
+ return 1 if $need_queue;
+
+ $self->{write_buf_size} -= $written;
+ shift @{$self->{write_buf}};
+ undef $bref;
+ next WRITE;
+ }
+ }
+}
+
+sub on_incomplete_write {
+ my PublicInbox::DS $self = shift;
+ $self->{write_set_watch} = 1 unless $self->{event_watch} & POLLOUT;
+ $self->watch_write(1);
+}
+
+=head2 C<< $obj->push_back_read( $buf ) >>
+
+Push back I<buf> (a scalar or scalarref) into the read stream. Useful if you read
+more than you need to and want to return this data on the next "read".
+
+=cut
+sub push_back_read {
+ my PublicInbox::DS $self = shift;
+ my $buf = shift;
+ push @{$self->{read_push_back}}, ref $buf ? $buf : \$buf;
+ $PushBackSet{$self->{fd}} = $self;
+}
+
+=head2 C<< $obj->read( $bytecount ) >>
+
+Read at most I<bytecount> bytes from the underlying handle; returns scalar
+ref on read, or undef on connection closed.
+
+=cut
+sub read {
+ my PublicInbox::DS $self = shift;
+ return if $self->{closed};
+ my $bytes = shift;
+ my $buf;
+ my $sock = $self->{sock};
+
+ if (@{$self->{read_push_back}}) {
+ $buf = shift @{$self->{read_push_back}};
+ my $len = length($$buf);
+
+ if ($len <= $bytes) {
+ delete $PushBackSet{$self->{fd}} unless @{$self->{read_push_back}};
+ return $buf;
+ } else {
+ # if the pushed back read is too big, we have to split it
+ my $overflow = substr($$buf, $bytes);
+ $buf = substr($$buf, 0, $bytes);
+ unshift @{$self->{read_push_back}}, \$overflow;
+ return \$buf;
+ }
+ }
+
+ # if this is too high, perl quits(!!). reports on mailing lists
+ # don't seem to point to a universal answer. 5MB worked for some,
+ # crashed for others. 1MB works for more people. let's go with 1MB
+ # for now. :/
+ my $req_bytes = $bytes > 1048576 ? 1048576 : $bytes;
+
+ my $res = sysread($sock, $buf, $req_bytes, 0);
+ DebugLevel >= 2 && $self->debugmsg("sysread = %d; \$! = %d", $res, $!);
+
+ if (! $res && $! != EWOULDBLOCK) {
+ # catches 0=conn closed or undef=error
+ DebugLevel >= 2 && $self->debugmsg("Fd \#%d read hit the end of the road.", $self->{fd});
+ return undef;
+ }
+
+ return \$buf;
+}
+
+=head2 (VIRTUAL) C<< $obj->event_read() >>
+
+Readable event handler. Concrete deriviatives of PublicInbox::DS should
+provide an implementation of this. The default implementation will die if
+called.
+
+=cut
+sub event_read { die "Base class event_read called for $_[0]\n"; }
+
+=head2 (VIRTUAL) C<< $obj->event_err() >>
+
+Error event handler. Concrete deriviatives of PublicInbox::DS should
+provide an implementation of this. The default implementation will die if
+called.
+
+=cut
+sub event_err { die "Base class event_err called for $_[0]\n"; }
+
+=head2 (VIRTUAL) C<< $obj->event_hup() >>
+
+'Hangup' event handler. Concrete deriviatives of PublicInbox::DS should
+provide an implementation of this. The default implementation will die if
+called.
+
+=cut
+sub event_hup { die "Base class event_hup called for $_[0]\n"; }
+
+=head2 C<< $obj->event_write() >>
+
+Writable event handler. Concrete deriviatives of PublicInbox::DS may wish to
+provide an implementation of this. The default implementation calls
+C<write()> with an C<undef>.
+
+=cut
+sub event_write {
+ my $self = shift;
+ $self->write(undef);
+}
+
+=head2 C<< $obj->watch_read( $boolean ) >>
+
+Turn 'readable' event notification on or off.
+
+=cut
+sub watch_read {
+ my PublicInbox::DS $self = shift;
+ return if $self->{closed} || !$self->{sock};
+
+ my $val = shift;
+ my $event = $self->{event_watch};
+
+ $event &= ~POLLIN if ! $val;
+ $event |= POLLIN if $val;
+
+ # If it changed, set it
+ if ($event != $self->{event_watch}) {
+ if ($HaveKQueue) {
+ $KQueue->EV_SET($self->{fd}, IO::KQueue::EVFILT_READ(),
+ $val ? IO::KQueue::EV_ENABLE() : IO::KQueue::EV_DISABLE());
+ }
+ elsif ($HaveEpoll) {
+ epoll_ctl($Epoll, EPOLL_CTL_MOD, $self->{fd}, $event)
+ and $self->dump_error("couldn't modify epoll settings for $self->{fd} " .
+ "from $self->{event_watch} -> $event: $! (" . ($!+0) . ")");
+ }
+ $self->{event_watch} = $event;
+ }
+}
+
+=head2 C<< $obj->watch_write( $boolean ) >>
+
+Turn 'writable' event notification on or off.
+
+=cut
+sub watch_write {
+ my PublicInbox::DS $self = shift;
+ return if $self->{closed} || !$self->{sock};
+
+ my $val = shift;
+ my $event = $self->{event_watch};
+
+ $event &= ~POLLOUT if ! $val;
+ $event |= POLLOUT if $val;
+
+ if ($val && caller ne __PACKAGE__) {
+ # A subclass registered interest, it's now responsible for this.
+ $self->{write_set_watch} = 0;
+ }
+
+ # If it changed, set it
+ if ($event != $self->{event_watch}) {
+ if ($HaveKQueue) {
+ $KQueue->EV_SET($self->{fd}, IO::KQueue::EVFILT_WRITE(),
+ $val ? IO::KQueue::EV_ENABLE() : IO::KQueue::EV_DISABLE());
+ }
+ elsif ($HaveEpoll) {
+ epoll_ctl($Epoll, EPOLL_CTL_MOD, $self->{fd}, $event)
+ and $self->dump_error("couldn't modify epoll settings for $self->{fd} " .
+ "from $self->{event_watch} -> $event: $! (" . ($!+0) . ")");
+ }
+ $self->{event_watch} = $event;
+ }
+}
+
+=head2 C<< $obj->dump_error( $message ) >>
+
+Prints to STDERR a backtrace with information about this socket and what lead
+up to the dump_error call.
+
+=cut
+sub dump_error {
+ my $i = 0;
+ my @list;
+ while (my ($file, $line, $sub) = (caller($i++))[1..3]) {
+ push @list, "\t$file:$line called $sub\n";
+ }
+
+ warn "ERROR: $_[1]\n" .
+ "\t$_[0] = " . $_[0]->as_string . "\n" .
+ join('', @list);
+}
+
+=head2 C<< $obj->debugmsg( $format, @args ) >>
+
+Print the debugging message specified by the C<sprintf>-style I<format> and
+I<args>.
+
+=cut
+sub debugmsg {
+ my ( $self, $fmt, @args ) = @_;
+ confess "Not an object" unless ref $self;
+
+ chomp $fmt;
+ printf STDERR ">>> $fmt\n", @args;
+}
+
+
+=head2 C<< $obj->peer_ip_string() >>
+
+Returns the string describing the peer's IP
+
+=cut
+sub peer_ip_string {
+ my PublicInbox::DS $self = shift;
+ return _undef("peer_ip_string undef: no sock") unless $self->{sock};
+ return $self->{peer_ip} if defined $self->{peer_ip};
+
+ my $pn = getpeername($self->{sock});
+ return _undef("peer_ip_string undef: getpeername") unless $pn;
+
+ my ($port, $iaddr) = eval {
+ if (length($pn) >= 28) {
+ return Socket6::unpack_sockaddr_in6($pn);
+ } else {
+ return Socket::sockaddr_in($pn);
+ }
+ };
+
+ if ($@) {
+ $self->{peer_port} = "[Unknown peerport '$@']";
+ return "[Unknown peername '$@']";
+ }
+
+ $self->{peer_port} = $port;
+
+ if (length($iaddr) == 4) {
+ return $self->{peer_ip} = Socket::inet_ntoa($iaddr);
+ } else {
+ $self->{peer_v6} = 1;
+ return $self->{peer_ip} = Socket6::inet_ntop(Socket6::AF_INET6(),
+ $iaddr);
+ }
+}
+
+=head2 C<< $obj->peer_addr_string() >>
+
+Returns the string describing the peer for the socket which underlies this
+object in form "ip:port"
+
+=cut
+sub peer_addr_string {
+ my PublicInbox::DS $self = shift;
+ my $ip = $self->peer_ip_string
+ or return undef;
+ return $self->{peer_v6} ?
+ "[$ip]:$self->{peer_port}" :
+ "$ip:$self->{peer_port}";
+}
+
+=head2 C<< $obj->local_ip_string() >>
+
+Returns the string describing the local IP
+
+=cut
+sub local_ip_string {
+ my PublicInbox::DS $self = shift;
+ return _undef("local_ip_string undef: no sock") unless $self->{sock};
+ return $self->{local_ip} if defined $self->{local_ip};
+
+ my $pn = getsockname($self->{sock});
+ return _undef("local_ip_string undef: getsockname") unless $pn;
+
+ my ($port, $iaddr) = Socket::sockaddr_in($pn);
+ $self->{local_port} = $port;
+
+ return $self->{local_ip} = Socket::inet_ntoa($iaddr);
+}
+
+=head2 C<< $obj->local_addr_string() >>
+
+Returns the string describing the local end of the socket which underlies this
+object in form "ip:port"
+
+=cut
+sub local_addr_string {
+ my PublicInbox::DS $self = shift;
+ my $ip = $self->local_ip_string;
+ return $ip ? "$ip:$self->{local_port}" : undef;
+}
+
+
+=head2 C<< $obj->as_string() >>
+
+Returns a string describing this socket.
+
+=cut
+sub as_string {
+ my PublicInbox::DS $self = shift;
+ my $rw = "(" . ($self->{event_watch} & POLLIN ? 'R' : '') .
+ ($self->{event_watch} & POLLOUT ? 'W' : '') . ")";
+ my $ret = ref($self) . "$rw: " . ($self->{closed} ? "closed" : "open");
+ my $peer = $self->peer_addr_string;
+ if ($peer) {
+ $ret .= " to " . $self->peer_addr_string;
+ }
+ return $ret;
+}
+
+sub _undef {
+ return undef unless $ENV{DS_DEBUG};
+ my $msg = shift || "";
+ warn "PublicInbox::DS: $msg\n";
+ return undef;
+}
+
+package PublicInbox::DS::Timer;
+# [$abs_float_firetime, $coderef];
+sub cancel {
+ $_[0][1] = undef;
+}
+
+1;
+
+=head1 AUTHORS (Danga::Socket)
+
+Brad Fitzpatrick <brad@danga.com> - author
+
+Michael Granger <ged@danga.com> - docs, testing
+
+Mark Smith <junior@danga.com> - contributor, heavy user, testing
+
+Matt Sergeant <matt@sergeant.org> - kqueue support, docs, timers, other bits