imap+nntp: share COMPRESS implementation

[public-inbox.git] / lib / PublicInbox / Listener.pm

diff --git a/lib/PublicInbox/Listener.pm b/lib/PublicInbox/Listener.pm
index 594dabb83e38eacd2b2733c952c205e3ffdc2456..7cedc3493f872df866755e1c2c9d5d545df7c319 100644 (file)
--- a/lib/PublicInbox/Listener.pm
+++ b/lib/PublicInbox/Listener.pm
@@ -1,26 +1,28 @@
-# Copyright (C) 2015-2018 all contributors <meta@public-inbox.org>
+# Copyright (C) 2015-2021 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 #
 # Used by -nntpd for listen sockets
 package PublicInbox::Listener;
 use strict;
-use warnings;
-use base 'PublicInbox::DS';
+use parent 'PublicInbox::DS';
 use Socket qw(SOL_SOCKET SO_KEEPALIVE IPPROTO_TCP TCP_NODELAY);
-use fields qw(post_accept);
-require IO::Handle;
-use PublicInbox::Syscall qw(EPOLLIN EPOLLEXCLUSIVE EPOLLET);
+use IO::Handle;
+use PublicInbox::Syscall qw(EPOLLIN EPOLLEXCLUSIVE);
+use Errno qw(EAGAIN ECONNABORTED);
+
+# Warn on transient errors, mostly resource limitations.
+# EINTR would indicate the failure to set NonBlocking in systemd or similar
+my %ERR_WARN = map {;
+       eval("Errno::$_()") => $_
+} qw(EMFILE ENFILE ENOBUFS ENOMEM EINTR);
 
 sub new ($$$) {
        my ($class, $s, $cb) = @_;
        setsockopt($s, SOL_SOCKET, SO_KEEPALIVE, 1);
        setsockopt($s, IPPROTO_TCP, TCP_NODELAY, 1); # ignore errors on non-TCP
-       listen($s, 1024);
-       IO::Handle::blocking($s, 0);
-       my $self = fields::new($class);
-       $self->SUPER::new($s, EPOLLIN|EPOLLET|EPOLLEXCLUSIVE);
-       $self->{post_accept} = $cb;
-       $self
+       listen($s, 2**31 - 1); # kernel will clamp
+       my $self = bless { post_accept => $cb }, $class;
+       $self->SUPER::new($s, EPOLLIN|EPOLLEXCLUSIVE);
 }
 
 sub event_step {
@@ -34,8 +36,16 @@ sub event_step {
        # on high-traffic sites.
        if (my $addr = accept(my $c, $sock)) {
                IO::Handle::blocking($c, 0); # no accept4 :<
-               $self->{post_accept}->($c, $addr, $sock);
-               $self->requeue;
+               eval { $self->{post_accept}->($c, $addr, $sock) };
+               warn "E: $@\n" if $@;
+       } elsif ($! == EAGAIN || $! == ECONNABORTED) {
+               # EAGAIN is common and likely
+               # ECONNABORTED is common with bad connections
+               return;
+       } elsif (my $sym = $ERR_WARN{int($!)}) {
+               warn "W: accept(): $! ($sym)\n";
+       } else {
+               warn "BUG?: accept(): $!\n";
        }
 }