# Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
-# base class for remote IPC calls, requires Storable
-# TODO: this ought to be usable in SearchIdxShard
+# base class for remote IPC calls and workqueues, requires Storable or Sereal
package PublicInbox::IPC;
use strict;
use v5.10.1;
use Carp qw(confess croak);
-use PublicInbox::Sigfd;
+use PublicInbox::DS qw(dwaitpid);
+use PublicInbox::Spawn;
use POSIX ();
+use Socket qw(AF_UNIX MSG_EOR);
+my $SEQPACKET = eval { Socket::SOCK_SEQPACKET() }; # portable enough?
use constant PIPE_BUF => $^O eq 'linux' ? 4096 : POSIX::_POSIX_PIPE_BUF();
my ($enc, $dec);
# ->imports at BEGIN turns sereal_*_with_object into custom ops on 5.14+
} // warn("Storable (part of Perl) missing: $@\n");
}
+my $recv_cmd = PublicInbox::Spawn->can('recv_cmd4');
+my $send_cmd = PublicInbox::Spawn->can('send_cmd4') // do {
+ require PublicInbox::CmdIPC4;
+ $recv_cmd //= PublicInbox::CmdIPC4->can('recv_cmd4');
+ PublicInbox::CmdIPC4->can('send_cmd4');
+} // do {
+ require PublicInbox::CmdIPC1;
+ $recv_cmd = PublicInbox::CmdIPC1->can('recv_cmd1');
+ PublicInbox::CmdIPC1->can('send_cmd1');
+};
+
sub _get_rec ($) {
my ($r) = @_;
defined(my $len = <$r>) or return;
# allow any sibling to send ipc_worker_exit, but siblings can't wait
return if $$ != $ppid;
- PublicInbox::DS::dwaitpid($pid, \&ipc_worker_reap, $self);
+ dwaitpid($pid, \&ipc_worker_reap, $self);
}
# use this if we have multiple readers reading curl or "pigz -dc"
$pid == $$ and die "BUG: $$ ipc_atfork_child called on itself";
}
+sub wq_worker_loop ($$) {
+ my ($self, $s2) = @_;
+ my $buf;
+ my $len = $self->{wq_req_len} // (4096 * 33);
+ my ($rec, $sub, @args);
+ while (1) {
+ my (@fds) = $recv_cmd->($s2, $buf, $len) or return; # EOF
+ my $i = 0;
+ my @m = @{$self->{wq_open_modes} // [qw( +<&= >&= >&= )]};
+ for my $fd (@fds) {
+ my $mode = shift(@m);
+ if (open(my $fh, $mode, $fd)) {
+ $self->{$i++} = $fh;
+ } else {
+ die "$$ open($mode$fd) (FD:$i): $!";
+ }
+ }
+ # Sereal dies, Storable returns undef
+ $rec = thaw($buf) //
+ die "thaw error on buffer of size:".length($buf);
+ ($sub, @args) = @$rec;
+ eval { $self->$sub(@args) };
+ warn "$$ wq_worker: $@" if $@;
+ delete @$self{0, 1, 2};
+ }
+}
+
+sub wq_do { # always async
+ my ($self, $sub, $in, $out, $err, @args) = @_;
+ if (my $s1 = $self->{-wq_seq}) { # run in worker
+ $_ = fileno($_) for ($in, $out, $err);
+ $send_cmd->($s1, $in, $out, $err,
+ freeze([$sub, @args]), MSG_EOR);
+ } else {
+ @$self{0, 1, 2} = ($in, $out, $err);
+ eval { $self->$sub(@args) };
+ warn "wq_do: $@" if $@;
+ delete @$self{0, 1, 2};
+ }
+}
+
+# starts workqueue workers if Sereal or Storable is installed
+sub wq_workers_start {
+ my ($self, $ident, $nr_workers, $oldset) = @_;
+ ($enc && $send_cmd && $recv_cmd && defined($SEQPACKET)) or return;
+ return if $self->{-wq_seq}; # idempotent
+ my ($s1, $s2);
+ socketpair($s1, $s2, AF_UNIX, $SEQPACKET, 0) or die "socketpair: $!";
+ my $sigset = $oldset // PublicInbox::DS::block_signals();
+ $self->ipc_atfork_parent;
+ $nr_workers //= 4;
+ $self->{-wq_workers} = {};
+ for my $i (0..($nr_workers - 1)) {
+ defined(my $pid = fork) or die "fork: $!";
+ if ($pid == 0) {
+ eval { PublicInbox::DS->Reset };
+ $s1 = undef;
+ $SIG{$_} = 'IGNORE' for (qw(TERM INT QUIT));
+ local $0 = $ident."[$i]";
+ PublicInbox::DS::sig_setmask($oldset);
+ my $on_destroy = $self->ipc_atfork_child;
+ eval { wq_worker_loop($self, $s2) };
+ die "worker $ident PID:$$ died: $@\n" if $@;
+ exit;
+ } else {
+ $self->{-wq_workers}->{$pid} = $i;
+ }
+ }
+ PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+ $s2 = undef;
+ $self->{-wq_seq} = $s1;
+ $self->{-wq_ppid} = $$;
+}
+
+sub wq_close {
+ my ($self) = @_;
+ delete $self->{-wq_seq} or return;
+ my $ppid = delete $self->{-wq_ppid} // die 'BUG: no wq_ppid';
+ my $workers = delete $self->{-wq_workers} // die 'BUG: no wq_workers';
+ return if $ppid != $$; # can't reap siblings or parents
+ for my $pid (keys %$workers) {
+ dwaitpid($pid, \&ipc_worker_reap, $self);
+ }
+}
+
1;
use v5.10.1;
use Test::More;
use PublicInbox::TestCommon;
+use Fcntl qw(SEEK_SET);
require_ok 'PublicInbox::IPC';
state $once = eval <<'';
package PublicInbox::IPC;
sub test_undef { undef }
sub test_die { shift; die @_; 'unreachable' }
sub test_pid { $$ }
+sub test_write_each_fd {
+ my ($self, @args) = @_;
+ for my $fd (0..2) {
+ print { $self->{$fd} } "i=$fd $$ ", @args, "\n";
+ $self->{$fd}->flush;
+ }
+}
1;
my $ipc = bless {}, 'PublicInbox::IPC';
ok(!kill(0, $pid) && $!{ESRCH}, 'worker stopped');
}
$ipc->ipc_worker_stop; # idempotent
+
+# work queues
+$ipc->{wq_open_modes} = [qw( >&= >&= >&= )];
+pipe(my ($ra, $wa)) or BAIL_OUT $!;
+pipe(my ($rb, $wb)) or BAIL_OUT $!;
+pipe(my ($rc, $wc)) or BAIL_OUT $!;
+open my $warn, '+>', undef or BAIL_OUT;
+$warn->autoflush(0);
+local $SIG{__WARN__} = sub { print $warn "PID:$$ ", @_ };
+my @ppids;
+for my $t ('local', 'worker', 'worker again') {
+ $ipc->wq_do('test_write_each_fd', $wa, $wb, $wc, 'hello world');
+ my $i = 0;
+ for my $fh ($ra, $rb, $rc) {
+ my $buf = readline($fh);
+ is(chop($buf), "\n", "trailing CR ($t)");
+ like($buf, qr/\Ai=$i \d+ hello world\z/, "got expected ($t)");
+ $i++;
+ }
+ $ipc->wq_do('test_die', $wa, $wb, $wc);
+ my $ppid = $ipc->wq_workers_start('wq', 1);
+ push(@ppids, $ppid);
+}
+
+# wq_do works across fork (siblings can feed)
+SKIP: {
+ skip 'Socket::MsgHdr, IO::FDPass, Inline::C missing', 7 if !$ppids[0];
+ is_deeply(\@ppids, [$$, undef, undef],
+ 'parent pid returned in wq_workers_start');
+ my $pid = fork // BAIL_OUT $!;
+ if ($pid == 0) {
+ use POSIX qw(_exit);
+ $ipc->wq_do('test_write_each_fd', $wa, $wb, $wc, $$);
+ _exit(0);
+ } else {
+ my $i = 0;
+ my ($wpid, @rest) = keys %{$ipc->{-wq_workers}};
+ is(scalar(@rest), 0, 'only one worker');
+ for my $fh ($ra, $rb, $rc) {
+ my $buf = readline($fh);
+ is(chop($buf), "\n", "trailing CR #$i");
+ like($buf, qr/^i=$i $wpid $pid\z/,
+ 'got expected from sibling');
+ $i++;
+ }
+ is(waitpid($pid, 0), $pid, 'waitpid complete');
+ is($?, 0, 'child wq producer exited');
+ }
+}
+
+$ipc->wq_close;
+seek($warn, 0, SEEK_SET) or BAIL_OUT;
+my @warn = <$warn>;
+is(scalar(@warn), 3, 'warned 3 times');
+like($warn[0], qr/ wq_do: /, '1st warned from wq_do');
+like($warn[1], qr/ wq_worker: /, '2nd warned from wq_worker');
+is($warn[2], $warn[1], 'worker did not die');
+
done_testing;