X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSpawnPP.pm;h=6d7e2c34ec9046111056b350084c947dbaa070e0;hb=23af251dd607c4e75ab1e68063f2c885c48cc035;hp=d0df94d0ded0f4cf179a2420a274e13da062be6d;hpb=3d41aa23f35501ca92aab8aa42980fa73f7fa74f;p=public-inbox.git

diff --git a/lib/PublicInbox/SpawnPP.pm b/lib/PublicInbox/SpawnPP.pm
index d0df94d0..6d7e2c34 100644
--- a/lib/PublicInbox/SpawnPP.pm
+++ b/lib/PublicInbox/SpawnPP.pm
@@ -1,45 +1,74 @@
-# Copyright (C) 2016-2018 all contributors <meta@public-inbox.org>
+# Copyright (C) 2016-2021 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.
 package PublicInbox::SpawnPP;
 use strict;
-use warnings;
-use POSIX qw(dup2 :signal_h);
+use v5.10.1;
+use POSIX qw(dup2 _exit setpgid :signal_h);
 
 # Pure Perl implementation for folks that do not use Inline::C
-sub public_inbox_fork_exec ($$$$$$) {
-	my ($in, $out, $err, $f, $cmd, $env) = @_;
+sub pi_fork_exec ($$$$$$$) {
+	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: $!";
 	my $syserr;
+	pipe(my ($r, $w));
 	my $pid = fork;
 	unless (defined $pid) { # compat with Inline::C version
 		$syserr = $!;
 		$pid = -1;
 	}
 	if ($pid == 0) {
-		if ($in != 0) {
-			dup2($in, 0) or die "dup2 failed for stdin: $!";
+		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): $!";
 		}
-		if ($out != 1) {
-			dup2($out, 1) or die "dup2 failed for stdout: $!";
+		if ($pgid >= 0 && !defined(setpgid(0, $pgid))) {
+			die "setpgid(0, $pgid): $!";
 		}
-		if ($err != 2) {
-			dup2($err, 2) or die "dup2 failed for stderr: $!";
+		for (keys %SIG) {
+			$SIG{$_} = 'DEFAULT' if substr($_, 0, 1) ne '_';
 		}
-
+		if ($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 "delset SIGCHLD: $!";
+		sigprocmask(SIG_SETMASK, $old) or die "SETMASK: ~SIGCHLD: $!";
+		$cmd->[0] = $f;
 		if ($ENV{MOD_PERL}) {
-			exec qw(env -i), @$env, @$cmd;
-			die "exec env -i ... $cmd->[0] failed: $!\n";
+			@$cmd = (which('env'), '-i', @$env, @$cmd);
 		} else {
-			local %ENV = map { split(/=/, $_, 2) } @$env;
-			exec @$cmd;
-			die "exec $cmd->[0] failed: $!\n";
+			%ENV = map { split(/=/, $_, 2) } @$env;
 		}
+		undef $r;
+		exec { $f } @$cmd;
+		die "exec @$cmd failed: $!";
 	}
+	close $w;
 	sigprocmask(SIG_SETMASK, $old) or die "can't unblock signals: $!";
-	$! = $syserr;
+	if (my $cerrnum = do { local $/, <$r> }) {
+		$pid = -1;
+		$! = $cerrnum;
+	} else {
+		$! = $syserr;
+	}
 	$pid;
 }