use Carp qw(confess carp);
my $nextq; # queue for next_tick
-my $WaitPids; # list of [ pid, callback, callback_arg ]
-my $later_queue; # callbacks
-my $EXPMAP; # fd -> [ idle_time, $self ]
+my $wait_pids; # list of [ pid, callback, callback_arg ]
+my $later_queue; # list of callbacks to run at some later interval
+my $EXPMAP; # fd -> idle_time
our $EXPTIME = 180; # 3 minutes
my ($later_timer, $reap_timer, $exp_timer);
my $ToClose; # sockets to close when event loop is done
=cut
sub Reset {
%DescriptorMap = ();
- $nextq = [];
- $WaitPids = [];
- $later_queue = [];
+ $wait_pids = $later_queue = undef;
$EXPMAP = {};
- $ToClose = $reap_timer = $later_timer = $exp_timer = undef;
+ $nextq = $ToClose = $reap_timer = $later_timer = $exp_timer = undef;
$LoopTimeout = -1; # no timeout by default
@Timers = ();
sub now () { clock_gettime(CLOCK_MONOTONIC) }
sub next_tick () {
- my $q = $nextq;
- $nextq = [];
+ my $q = $nextq or return;
+ $nextq = undef;
for (@$q) {
# we avoid "ref" on blessed refs to workaround a Perl 5.16.3 leak:
# https://rt.perl.org/Public/Bug/Display.html?id=114340
sub RunTimers {
next_tick();
- return ((@$nextq || $ToClose) ? 0 : $LoopTimeout) unless @Timers;
+ return (($nextq || $ToClose) ? 0 : $LoopTimeout) unless @Timers;
my $now = now();
}
# timers may enqueue into nextq:
- return 0 if (@$nextq || $ToClose);
+ return 0 if ($nextq || $ToClose);
return $LoopTimeout unless @Timers;
}
# 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.
+# and other things. So we scan the $wait_pids list, which is hopefully
+# not too big. We keep $wait_pids small by not calling dwaitpid()
+# until we've hit EOF when reading the stdout of the child.
sub reap_pids {
- my $tmp = $WaitPids;
- $WaitPids = [];
- $reap_timer = undef;
+ my $tmp = $wait_pids or return;
+ $wait_pids = $reap_timer = undef;
foreach my $ary (@$tmp) {
my ($pid, $cb, $arg) = @$ary;
my $ret = waitpid($pid, WNOHANG);
if ($ret == 0) {
- push @$WaitPids, $ary;
+ push @$wait_pids, $ary; # autovivifies @$wait_pids
} 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);
- }
+ # we may not be done, yet, and could've missed/masked a SIGCHLD:
+ $reap_timer = add_timer(1, \&reap_pids) if $wait_pids;
}
# reentrant SIGCHLD handler (since reap_pids is not reentrant)
-sub enqueue_reap ($) { push @$nextq, \&reap_pids };
+sub enqueue_reap ($) { push @$nextq, \&reap_pids }; # autovivifies
sub in_loop () { $in_loop }
# loop)
if (my $close_now = $ToClose) {
$ToClose = undef; # will be autovivified on push
+ @$close_now = map { fileno($_) } @$close_now;
+
+ # order matters, destroy expiry times, first:
+ delete @$EXPMAP{@$close_now};
+
# ->DESTROY methods may populate ToClose
- delete($DescriptorMap{fileno($_)}) for @$close_now;
- # let refcounting drop everything in $close_now at once
+ delete @DescriptorMap{@$close_now};
}
# by default we keep running, unless a postloop callback cancels it
### I N S T A N C E M E T H O D S
#####################################################################
-sub requeue ($) { push @$nextq, $_[0] }
+sub requeue ($) { push @$nextq, $_[0] } # autovivifies
=head2 C<< $obj->close >>
# 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 ];
+ die "Not in EventLoop\n" unless $in_loop;
+ push @$wait_pids, [ @_ ]; # [ $pid, $cb, $arg ]
- # We could've just missed our SIGCHLD, cover it, here:
- requeue(\&reap_pids);
- } else {
- die "Not in EventLoop\n";
- }
+ # We could've just missed our SIGCHLD, cover it, here:
+ requeue(\&reap_pids);
}
sub _run_later () {
- my $run = $later_queue;
- $later_timer = undef;
- $later_queue = [];
- $_->() for @$run;
+ my $run = $later_queue or return;
+ $later_timer = $later_queue = undef;
+ $_->() for @$run;
}
sub later ($) {
- my ($cb) = @_;
- push @$later_queue, $cb;
- $later_timer //= add_timer(60, \&_run_later);
+ push @$later_queue, $_[0]; # autovivifies @$later_queue
+ $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;
+ my $now = now();
+ my $exp = $EXPTIME;
+ my $old = $now - $exp;
+ my %new;
+ while (my ($fd, $idle_at) = each %$EXPMAP) {
+ if ($idle_at < $old) {
+ my $ds_obj = $DescriptorMap{$fd};
+ $new{$fd} = $idle_at if !$ds_obj->shutdn;
+ } else {
+ $new{$fd} = $idle_at;
+ }
+ }
+ $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 ];
- $exp_timer //= later(\&expire_old);
+ my ($self) = @_;
+ my $sock = $self->{sock} or return;
+ $EXPMAP->{fileno($sock)} = now();
+ $exp_timer //= later(\&expire_old);
}
sub not_idle_long {
- my ($self, $now) = @_;
- my $sock = $self->{sock} or return;
- my $ary = $EXPMAP->{fileno($sock)} or return;
- my $exp_at = $ary->[0] + $EXPTIME;
- $exp_at > $now;
+ my ($self, $now) = @_;
+ my $sock = $self->{sock} or return;
+ my $idle_at = $EXPMAP->{fileno($sock)} or return;
+ ($idle_at + $EXPTIME) > $now;
}
1;