watch: switch to awaitpid

-watch relies on our event_loop anyways, and awaitpid lets us
avoid the extra overhead of EOFpipe.  Add an extra {quit} check
in imap_idle_fork while we're at it.

diff --git a/lib/PublicInbox/Watch.pm b/lib/PublicInbox/Watch.pm
index 082ecfb96baf5e05021fca165551d5e40cac4a87..5798508340dda6c2ba76d4afe6b2d9e5212dd926 100644 (file)
--- a/lib/PublicInbox/Watch.pm
+++ b/lib/PublicInbox/Watch.pm
@@ -1,4 +1,4 @@
-# Copyright (C) 2016-2021 all contributors <meta@public-inbox.org>
+# Copyright (C) all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 #
 # ref: https://cr.yp.to/proto/maildir.html
@@ -12,10 +12,9 @@ use PublicInbox::MdirReader;
 use PublicInbox::NetReader;
 use PublicInbox::Filter::Base qw(REJECT);
 use PublicInbox::Spamcheck;
-use PublicInbox::DS qw(now add_timer);
+use PublicInbox::DS qw(now add_timer awaitpid);
 use PublicInbox::MID qw(mids);
 use PublicInbox::ContentHash qw(content_hash);
-use PublicInbox::EOFpipe;
 use POSIX qw(_exit WNOHANG);
 
 sub compile_watchheaders ($) {
@@ -244,14 +243,13 @@ sub quit_done ($) {
        return unless $self->{quit};
 
        # don't have reliable wakeups, keep signalling
-       my $done = 1;
+       my $live = 0;
        for (qw(idle_pids poll_pids)) {
                my $pids = $self->{$_} or next;
-               for (keys %$pids) {
-                       $done = undef if kill('QUIT', $_);
-               }
+               $live += grep { kill('QUIT', $_) } keys %$pids;
        }
-       $done;
+       add_timer(0.01, \&quit_done, $self) if $live;
+       $live == 0;
 }
 
 sub quit {
@@ -400,8 +398,8 @@ sub imap_idle_requeue { # DS::add_timer callback
        event_step($self);
 }
 
-sub imap_idle_reap { # PublicInbox::DS::dwaitpid callback
-       my ($self, $pid) = @_;
+sub imap_idle_reap { # awaitpid callback
+       my ($pid, $self) = @_;
        my $uri_intvl = delete $self->{idle_pids}->{$pid} or
                die "BUG: PID=$pid (unknown) reaped: \$?=$?\n";
 
@@ -411,33 +409,21 @@ sub imap_idle_reap { # PublicInbox::DS::dwaitpid callback
        add_timer(60, \&imap_idle_requeue, $self, $uri_intvl);
 }
 
-sub reap { # callback for EOFpipe
-       my ($pid, $cb, $self) = @{$_[0]};
-       my $ret = waitpid($pid, 0);
-       if ($ret == $pid) {
-               $cb->($self, $pid); # poll_fetch_reap || imap_idle_reap
-       } else {
-               warn "W: waitpid($pid) => ", $ret // "($!)", "\n";
-       }
-}
-
 sub imap_idle_fork ($$) {
        my ($self, $uri_intvl) = @_;
+       return if $self->{quit};
        my ($uri, $intvl) = @$uri_intvl;
-       pipe(my ($r, $w)) or die "pipe: $!";
        my $seed = rand(0xffffffff);
        my $pid = fork // die "fork: $!";
        if ($pid == 0) {
                srand($seed);
                eval { Net::SSLeay::randomize() };
-               close $r;
                watch_atfork_child($self);
                watch_imap_idle_1($self, $uri, $intvl);
-               close $w;
                _exit(0);
        }
        $self->{idle_pids}->{$pid} = $uri_intvl;
-       PublicInbox::EOFpipe->new($r, \&reap, [$pid, \&imap_idle_reap, $self]);
+       awaitpid($pid, \&imap_idle_reap, $self);
 }
 
 sub event_step {
@@ -486,30 +472,26 @@ sub watch_nntp_fetch_all ($$) {
 sub poll_fetch_fork { # DS::add_timer callback
        my ($self, $intvl, $uris) = @_;
        return if $self->{quit};
-       pipe(my ($r, $w)) or die "pipe: $!";
        watch_atfork_parent($self);
        my $seed = rand(0xffffffff);
-       my $pid = fork;
-       if (defined($pid) && $pid == 0) {
+       my $pid = fork // die "fork: $!";
+       if ($pid == 0) {
                srand($seed);
                eval { Net::SSLeay::randomize() };
-               close $r;
                watch_atfork_child($self);
                if ($uris->[0]->scheme =~ m!\Aimaps?!i) {
                        watch_imap_fetch_all($self, $uris);
                } else {
                        watch_nntp_fetch_all($self, $uris);
                }
-               close $w;
                _exit(0);
        }
-       die "fork: $!"  unless defined $pid;
        $self->{poll_pids}->{$pid} = [ $intvl, $uris ];
-       PublicInbox::EOFpipe->new($r, \&reap, [$pid, \&poll_fetch_reap, $self]);
+       awaitpid($pid, \&poll_fetch_reap, $self);
 }
 
-sub poll_fetch_reap {
-       my ($self, $pid) = @_;
+sub poll_fetch_reap { # awaitpid callback
+       my ($pid, $self) = @_;
        my $intvl_uris = delete $self->{poll_pids}->{$pid} or
                die "BUG: PID=$pid (unknown) reaped: \$?=$?\n";
        return if $self->{quit};