#
# 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.
+# This is a fork of the unmaintained Danga::Socket (1.61) with
+# significant changes. See Documentation/technical/ds.txt in our
+# source for details.
#
-# API changes to diverge from Danga::Socket will happen to better
-# accomodate new features and improve scalability. Do not expect
-# this to be a stable API like Danga::Socket.
-# Bugs encountered (and likely fixed) are reported to
-# bug-Danga-Socket@rt.cpan.org and visible at:
+# Do not expect this to be a stable API like Danga::Socket,
+# but it will evolve to suite our needs and to take advantage of
+# newer Linux and *BSD features.
+# Bugs encountered were reported to bug-Danga-Socket@rt.cpan.org,
+# fixed in Danga::Socket 1.62 and visible at:
# https://rt.cpan.org/Public/Dist/Display.html?Name=Danga-Socket
package PublicInbox::DS;
use strict;
use bytes;
-use POSIX ();
+use POSIX qw(WNOHANG);
use IO::Handle qw();
use Fcntl qw(SEEK_SET :DEFAULT);
use Time::HiRes qw(clock_gettime CLOCK_MONOTONIC);
our @EXPORT_OK = qw(now msg_more);
use warnings;
use 5.010_001;
+use Scalar::Util qw(blessed);
use PublicInbox::Syscall qw(:epoll);
+use PublicInbox::Tmpfile;
use fields ('sock', # underlying socket
'rbuf', # scalarref, usually undef
'wbuf_off', # offset into first element of wbuf to start writing at
);
-use Errno qw(EAGAIN EINVAL EEXIST);
-use Carp qw(croak confess carp);
-require File::Spec;
+use Errno qw(EAGAIN EINVAL);
+use Carp qw(confess carp);
-my $nextq = []; # queue for next_tick
+my $nextq; # queue for next_tick
+my $WaitPids; # list of [ pid, callback, callback_arg ]
+my $later_queue; # callbacks
+my $EXPMAP; # fd -> [ idle_time, $self ]
+our $EXPTIME = 180; # 3 minutes
+my ($later_timer, $reap_timer, $exp_timer);
our (
%DescriptorMap, # fd (num) -> PublicInbox::DS object
$Epoll, # Global epoll fd (or DSKQXS ref)
$LoopTimeout, # timeout of event loop in milliseconds
$DoneInit, # if we've done the one-time module init yet
@Timers, # timers
+ $in_loop,
);
Reset();
=cut
sub Reset {
%DescriptorMap = ();
+ $nextq = [];
+ $WaitPids = [];
+ $later_queue = [];
+ $EXPMAP = {};
+ $reap_timer = $later_timer = $exp_timer = undef;
@ToClose = ();
$LoopTimeout = -1; # no timeout by default
@Timers = ();
return $LoopTimeout = $_[1] + 0;
}
-=head2 C<< CLASS->AddTimer( $seconds, $coderef ) >>
+=head2 C<< PublicInbox::DS::add_timer( $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, $secs, $coderef) = @_;
+sub add_timer ($$) {
+ my ($secs, $coderef) = @_;
my $fire_time = now() + $secs;
- my $timer = bless [$fire_time, $coderef], "PublicInbox::DS::Timer";
+ my $timer = [$fire_time, $coderef];
if (!@Timers || $fire_time >= $Timers[-1][0]) {
push @Timers, $timer;
my $q = $nextq;
$nextq = [];
for (@$q) {
- if (ref($_) eq 'CODE') {
- $_->();
- } else {
+ # we avoid "ref" on blessed refs to workaround a Perl 5.16.3 leak:
+ # https://rt.perl.org/Public/Bug/Display.html?id=114340
+ if (blessed($_)) {
$_->event_step;
+ } else {
+ $_->();
}
}
}
return $timeout;
}
+# We can't use waitpid(-1) safely here since it can hit ``, system(),
+# and other things. So we scan the $WaitPids list, which is hopefully
+# not too big.
+sub reap_pids {
+ my $tmp = $WaitPids;
+ $WaitPids = [];
+ $reap_timer = undef;
+ foreach my $ary (@$tmp) {
+ my ($pid, $cb, $arg) = @$ary;
+ my $ret = waitpid($pid, WNOHANG);
+ if ($ret == 0) {
+ push @$WaitPids, $ary;
+ } elsif ($cb) {
+ eval { $cb->($arg, $pid) };
+ }
+ }
+ if (@$WaitPids) {
+ # we may not be donea, and we may miss our
+ $reap_timer = add_timer(1, \&reap_pids);
+ }
+}
+
+# reentrant SIGCHLD handler (since reap_pids is not reentrant)
+sub enqueue_reap ($) { push @$nextq, \&reap_pids };
+
+sub in_loop () { $in_loop }
+
sub EpollEventLoop {
- while (1) {
+ local $in_loop = 1;
+ do {
my @events;
my $i;
my $timeout = RunTimers();
# in that event.
$DescriptorMap{$events[$i]->[0]}->event_step;
}
- return unless PostEventLoop();
- }
+ } while (PostEventLoop());
+ _run_later();
}
=head2 C<< CLASS->SetPostLoopCallback( CODEREF ) >>
$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;
-
_InitPoller();
if (epoll_ctl($Epoll, EPOLL_CTL_ADD, $fd, $ev)) {
}
die "couldn't add epoll watch for $fd: $!\n";
}
- Carp::cluck("PublicInbox::DS::new blowing away existing descriptor map for fd=$fd ($DescriptorMap{$fd})")
- if $DescriptorMap{$fd};
+ confess("DescriptorMap{$fd} defined ($DescriptorMap{$fd})")
+ if defined($DescriptorMap{$fd});
$DescriptorMap{$fd} = $self;
- return $self;
}
# PerlIO::mmap or PerlIO::scalar if needed
sub tmpio ($$$) {
my ($self, $bref, $off) = @_;
- my $fh; # open(my $fh, '+>>', undef) doesn't set O_APPEND
- do {
- my $fn = File::Spec->tmpdir . '/wbuf-' . rand;
- if (sysopen($fh, $fn, O_RDWR|O_CREAT|O_EXCL|O_APPEND, 0600)) { # likely
- unlink($fn) or return drop($self, "unlink($fn) $!");
- } elsif ($! != EEXIST) { # EMFILE/ENFILE/ENOSPC/ENOMEM
- return drop($self, "open: $!");
- }
- } until (defined $fh);
+ my $fh = tmpfile('wbuf', $self->{sock}, 1) or
+ return drop($self, "tmpfile $!");
$fh->autoflush(1);
my $len = bytes::length($$bref) - $off;
$fh->write($$bref, $len, $off) or return drop($self, "write ($len): $!");
sub msg_more ($$) {
my $self = $_[0];
my $sock = $self->{sock} or return 1;
+ my $wbuf = $self->{wbuf};
- if (MSG_MORE && !$self->{wbuf} && ref($sock) ne 'IO::Socket::SSL') {
+ if (MSG_MORE && (!defined($wbuf) || !scalar(@$wbuf)) &&
+ ref($sock) ne 'IO::Socket::SSL') {
my $n = send($sock, $_[1], MSG_MORE);
if (defined $n) {
my $nlen = bytes::length($_[1]) - $n;
return 1 if $nlen == 0; # all done!
# queue up the unwritten substring:
my $tmpio = tmpio($self, \($_[1]), $n) or return 0;
- $self->{wbuf} = [ $tmpio ];
+ $self->{wbuf} //= $wbuf //= [];
+ push @$wbuf, $tmpio;
epwait($sock, EPOLLOUT|EPOLLONESHOT);
return 0;
}
}
- $self->write(\($_[1]));
+
+ # don't redispatch into NNTPdeflate::write
+ PublicInbox::DS::write($self, \($_[1]));
}
sub epwait ($$) {
$self->close;
}
}
-package PublicInbox::DS::Timer;
-# [$abs_float_firetime, $coderef];
-sub cancel {
- $_[0][1] = undef;
+
+# must be called with eval, PublicInbox::DS may not be loaded (see t/qspawn.t)
+sub dwaitpid ($$$) {
+ my ($pid, $cb, $arg) = @_;
+ if ($in_loop) {
+ push @$WaitPids, [ $pid, $cb, $arg ];
+
+ # We could've just missed our SIGCHLD, cover it, here:
+ requeue(\&reap_pids);
+ } else {
+ die "Not in EventLoop\n";
+ }
+}
+
+sub _run_later () {
+ my $run = $later_queue;
+ $later_timer = undef;
+ $later_queue = [];
+ $_->() for @$run;
+}
+
+sub later ($) {
+ my ($cb) = @_;
+ push @$later_queue, $cb;
+ $later_timer //= add_timer(60, \&_run_later);
+}
+
+sub expire_old () {
+ my $now = now();
+ my $exp = $EXPTIME;
+ my $old = $now - $exp;
+ my %new;
+ while (my ($fd, $v) = each %$EXPMAP) {
+ my ($idle_time, $ds_obj) = @$v;
+ if ($idle_time < $old) {
+ if (!$ds_obj->shutdn) {
+ $new{$fd} = $v;
+ }
+ } else {
+ $new{$fd} = $v;
+ }
+ }
+ $EXPMAP = \%new;
+ $exp_timer = scalar(keys %new) ? later(\&expire_old) : undef;
+}
+
+sub update_idle_time {
+ my ($self) = @_;
+ my $sock = $self->{sock} or return;
+ $EXPMAP->{fileno($sock)} = [ now(), $self ];
+ $exp_timer //= later(\&expire_old);
+}
+
+sub not_idle_long {
+ my ($self, $now) = @_;
+ my $sock = $self->{sock} or return;
+ my $ary = $EXPMAP->{fileno($sock)} or return;
+ my $exp_at = $ary->[0] + $EXPTIME;
+ $exp_at > $now;
}
1;