script/lei: background ourselves on MUA/pager exec

[public-inbox.git] / script / lei

diff --git a/script/lei b/script/lei
index b7f21f1410fab4237054542cd2cdfbec72b0f8c1..bea8dcde97ea1be5662f4a02803137ca981bafbb 100755 (executable)
--- a/script/lei
+++ b/script/lei
@@ -14,36 +14,31 @@ my $send_cmd = PublicInbox::CmdIPC4->can('send_cmd4') // do {
        PublicInbox::Spawn->can('send_cmd4');
 };
 
-my %pids;
-my $sigchld = sub {
-       my $flags = scalar(@_) ? POSIX::WNOHANG() : 0;
-       for my $pid (keys %pids) {
-               delete($pids{$pid}) if waitpid($pid, $flags) == $pid;
-       }
-};
-
+my @orig_pid;
 my $exec_cmd = sub {
        my ($fds, $argc, @argv) = @_;
+       die "BUG: already exec-ed\n" if @orig_pid;
+       @orig_pid = ($$);
+       require POSIX; # WNOHANG
        my @old = (*STDIN{IO}, *STDOUT{IO}, *STDERR{IO});
        my @rdr;
        for my $fd (@$fds) {
                open(my $tmpfh, '+<&=', $fd) or die "open +<&=$fd: $!";
                push @rdr, shift(@old), $tmpfh;
        }
-       require POSIX; # WNOHANG
-       $SIG{CHLD} = $sigchld;
        my $pid = fork // die "fork: $!";
        if ($pid == 0) {
-               my %env = map { split(/=/, $_, 2) } splice(@argv, $argc);
-               while (my ($old_io, $tmpfh) = splice(@rdr, 0, 2)) {
-                       open $old_io, '+<&', $tmpfh or die "open +<&=: $!";
-               }
-               %ENV = (%ENV, %env);
-               exec(@argv);
-               warn "exec: @argv: $!\n";
-               POSIX::_exit(1);
+               POSIX::setsid() > 0 or die "setsid: $!";
+               return; # continue $recv_cmd in background
        }
-       $pids{$pid} = 1;
+       my %env = map { split(/=/, $_, 2) } splice(@argv, $argc);
+       while (my ($old_io, $tmpfh) = splice(@rdr, 0, 2)) {
+               open $old_io, '+<&', $tmpfh or die "open +<&=: $!";
+       }
+       @ENV{keys %env} = values %env;
+       exec(@argv);
+       warn "exec: @argv: $!\n";
+       POSIX::_exit(1);
 };
 
 if ($send_cmd && eval {
@@ -82,14 +77,6 @@ Falling back to (slow) one-shot mode
        while (my ($k, $v) = each %ENV) { $buf .= "\0$k=$v" }
        $buf .= "\0\0";
        my $n = $send_cmd->($sock, [0, 1, 2, fileno($dh)], $buf, MSG_EOR);
-       if (!$n && $!{ETOOMANYREFS} && eval { require BSD::Resource }) {
-               my $NOFILE = BSD::Resource::RLIMIT_NOFILE();
-               my ($s, $h) = BSD::Resource::getrlimit($NOFILE);
-               if ($s < $h && BSD::Resource::setrlimit($NOFILE, $h, $h)) {
-                       $n = $send_cmd->($sock, [0, 1, 2, fileno($dh)],
-                                       $buf, MSG_EOR);
-               }
-       }
        if (!$n) {
                die "sendmsg: $! (check RLIMIT_NOFILE)\n" if $!{ETOOMANYREFS};
                die "sendmsg: $!\n";
@@ -105,19 +92,19 @@ Falling back to (slow) one-shot mode
                        die "recvmsg: $!";
                }
                last if $buf eq '';
-               if ($buf =~ /\Ax_it ([0-9]+)\z/) {
+               if ($buf =~ /\Aexec (.+)\z/) {
+                       $exec_cmd->(\@fds, split(/\0/, $1));
+               } elsif ($buf eq '-WINCH') {
+                       kill($buf, @orig_pid); # for MUA
+               } elsif ($buf =~ /\Ax_it ([0-9]+)\z/) {
                        $x_it_code = $1 + 0;
                        last;
                } elsif ($buf =~ /\Achild_error ([0-9]+)\z/) {
                        $x_it_code = $1 + 0;
-               } elsif ($buf =~ /\Aexec (.+)\z/) {
-                       $exec_cmd->(\@fds, split(/\0/, $1));
                } else {
-                       $sigchld->();
                        die $buf;
                }
        }
-       $sigchld->();
        if (my $sig = ($x_it_code & 127)) {
                kill $sig, $$;
                sleep(1) while 1;