# Copyright (C) 2019-2020 all contributors # License: AGPL-3.0+ # Wraps a signalfd (or similar) for PublicInbox::DS # fields: (sig: hashref similar to %SIG, but signal numbers as keys) package PublicInbox::Sigfd; use strict; use parent qw(PublicInbox::DS); use PublicInbox::Syscall qw(signalfd EPOLLIN EPOLLET $SFD_NONBLOCK); use POSIX qw(:signal_h); use IO::Handle (); # returns a coderef to unblock signals if neither signalfd or kqueue # are available. sub new { my ($class, $sig, $flags) = @_; my %signo = map {; my $cb = $sig->{$_}; # SIGWINCH is 28 on FreeBSD, NetBSD, OpenBSD my $num = ($_ eq 'WINCH' && $^O =~ /linux|bsd/i) ? 28 : do { my $m = "SIG$_"; POSIX->$m; }; $num => $cb; } keys %$sig; my $self = bless { sig => \%signo }, $class; my $io; my $fd = signalfd(-1, [keys %signo], $flags); if (defined $fd && $fd >= 0) { $io = IO::Handle->new_from_fd($fd, 'r+'); } elsif (eval { require PublicInbox::DSKQXS }) { $io = PublicInbox::DSKQXS->signalfd([keys %signo], $flags); } else { return; # wake up every second to check for signals } if ($flags & $SFD_NONBLOCK) { # it can go into the event loop $self->SUPER::new($io, EPOLLIN | EPOLLET); } else { # master main loop $self->{sock} = $io; $self; } } # PublicInbox::Daemon in master main loop (blocking) sub wait_once ($) { my ($self) = @_; # 128 == sizeof(struct signalfd_siginfo) my $r = sysread($self->{sock}, my $buf, 128 * 64); if (defined($r)) { my $nr = $r / 128 - 1; # $nr may be -1 for my $off (0..$nr) { # the first uint32_t of signalfd_siginfo: ssi_signo my $signo = unpack('L', substr($buf, 128 * $off, 4)); my $cb = $self->{sig}->{$signo}; $cb->($signo) if $cb ne 'IGNORE'; } } $r; } # called by PublicInbox::DS in epoll_wait loop sub event_step { while (wait_once($_[0])) {} # non-blocking } sub sig_setmask { sigprocmask(SIG_SETMASK, @_) or die "sigprocmask: $!" } sub block_signals () { my $oldset = POSIX::SigSet->new; my $newset = POSIX::SigSet->new; $newset->fillset or die "fillset: $!"; sig_setmask($newset, $oldset); $oldset; } 1;