X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSpawnPP.pm;h=5609f74a8781a49530fed377e031112ab4cdeead;hb=refs%2Fheads%2Fmaster;hp=2ac02c564c76e36b24353f1b32d85e3677c0c9ad;hpb=267371b1273b518215939e817e53733584b68af7;p=public-inbox.git

diff --git a/lib/PublicInbox/SpawnPP.pm b/lib/PublicInbox/SpawnPP.pm
index 2ac02c56..5609f74a 100644
--- a/lib/PublicInbox/SpawnPP.pm
+++ b/lib/PublicInbox/SpawnPP.pm
@@ -1,51 +1,67 @@
-# Copyright (C) 2016-2019 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>
 
 # Pure-Perl implementation of "spawn".  This can't take advantage
 # of vfork, so no speedups under Linux for spawning from large processes.
+# Do not require this directly, only use from PublicInbox::Spawn
 package PublicInbox::SpawnPP;
-use strict;
-use warnings;
-use POSIX qw(dup2 :signal_h);
+use v5.12;
+use POSIX qw(dup2 _exit setpgid :signal_h);
+# this is loaded by PublicInbox::Spawn, so we can't use/require it, here
 
 # Pure Perl implementation for folks that do not use Inline::C
-sub pi_fork_exec ($$$$$) {
-	my ($redir, $f, $cmd, $env, $rlim) = @_;
+sub pi_fork_exec ($$$$$$$) {
+	my ($redir, $f, $cmd, $env, $rlim, $cd, $pgid) = @_;
 	my $old = POSIX::SigSet->new();
 	my $set = POSIX::SigSet->new();
-	$set->fillset or die "fillset failed: $!";
-	sigprocmask(SIG_SETMASK, $set, $old) or die "can't block signals: $!";
+	$set->fillset or die "sigfillset: $!";
+	sigprocmask(SIG_SETMASK, $set, $old) or die "SIG_SETMASK(set): $!";
 	my $syserr;
-	my $pid = fork;
-	unless (defined $pid) { # compat with Inline::C version
-		$syserr = $!;
-		$pid = -1;
-	}
+	pipe(my ($r, $w)) or die "pipe: $!";
+	my $pid = fork // die "fork (+exec) @$cmd: $!\n";
 	if ($pid == 0) {
-		while (@$rlim) {
-			my ($r, $soft, $hard) = splice(@$rlim, 0, 3);
-			BSD::Resource::setrlimit($r, $soft, $hard) or
-			  warn "failed to set $r=[$soft,$hard]\n";
-		}
+		close $r;
+		$SIG{__DIE__} = sub {
+			warn(@_);
+			syswrite($w, my $num = $! + 0);
+			_exit(1);
+		};
 		for my $child_fd (0..$#$redir) {
 			my $parent_fd = $redir->[$child_fd];
 			next if $parent_fd == $child_fd;
 			dup2($parent_fd, $child_fd) or
-				die "dup2($parent_fd, $child_fd): $!\n";
+				die "dup2($parent_fd, $child_fd): $!";
+		}
+		if ($pgid >= 0 && !defined(setpgid(0, $pgid))) {
+			die "setpgid(0, $pgid): $!";
 		}
+		$SIG{$_} = 'DEFAULT' for grep(!/\A__/, keys %SIG);
+		if ($cd ne '') {
+			chdir $cd or die "chdir $cd: $!";
+		}
+		while (@$rlim) {
+			my ($r, $soft, $hard) = splice(@$rlim, 0, 3);
+			BSD::Resource::setrlimit($r, $soft, $hard) or
+				die "setrlimit($r=[$soft,$hard]: $!)";
+		}
+		$old->delset(POSIX::SIGCHLD) or die "sigdelset CHLD: $!";
+		sigprocmask(SIG_SETMASK, $old) or die "SIG_SETMASK ~CHLD: $!";
+		$cmd->[0] = $f;
 		if ($ENV{MOD_PERL}) {
-			exec which('env'), '-i', @$env, @$cmd;
-			die "exec env -i ... $cmd->[0] failed: $!\n";
+			$f = PublicInbox::Spawn::which('env');
+			@$cmd = ('env', '-i', @$env, @$cmd);
 		} else {
-			local %ENV = map { split(/=/, $_, 2) } @$env;
-			my @cmd = @$cmd;
-			$cmd[0] = $f;
-			exec @cmd;
-			die "exec $cmd->[0] failed: $!\n";
+			%ENV = map { split(/=/, $_, 2) } @$env;
 		}
+		exec { $f } @$cmd;
+		die "exec @$cmd failed: $!";
+	}
+	close $w;
+	sigprocmask(SIG_SETMASK, $old) or die "SIG_SETMASK(old): $!";
+	if (my $cerrnum = do { local $/, <$r> }) {
+		$! = $cerrnum;
+		die "forked child $@: $!";
 	}
-	sigprocmask(SIG_SETMASK, $old) or die "can't unblock signals: $!";
-	$! = $syserr;
 	$pid;
 }