X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FSpawn.pm;h=91a3c123e736635a833fcc6fefa810616349fb9c;hb=3d41aa23f35501ca92aab8aa42980fa73f7fa74f;hp=394a0b453e342cdf3ef4a2ac328d1125aa6721e6;hpb=617f35dacbd4e5972bf2d82411b45009bbc79a42;p=public-inbox.git

diff --git a/lib/PublicInbox/Spawn.pm b/lib/PublicInbox/Spawn.pm
index 394a0b45..91a3c123 100644
--- a/lib/PublicInbox/Spawn.pm
+++ b/lib/PublicInbox/Spawn.pm
@@ -1,4 +1,4 @@
-# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# Copyright (C) 2016-2018 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 #
 # This allows vfork to be used for spawning subprocesses if
@@ -15,6 +15,7 @@ use strict;
 use warnings;
 use base qw(Exporter);
 use Symbol qw(gensym);
+use IO::Handle;
 use PublicInbox::ProcessPipe;
 our @EXPORT_OK = qw/which spawn popen_rd/;
 
@@ -23,6 +24,8 @@ my $vfork_spawn = <<'VFORK_SPAWN';
 #include <sys/uio.h>
 #include <unistd.h>
 #include <alloca.h>
+#include <signal.h>
+#include <assert.h>
 
 #define AV_ALLOCA(av, max) alloca((max = (av_len((av)) + 1)) * sizeof(char *))
 
@@ -80,6 +83,8 @@ int public_inbox_fork_exec(int in, int out, int err,
 	pid_t pid;
 	char **argv, **envp;
 	I32 max;
+	sigset_t set, old;
+	int ret, errnum;
 
 	argv = AV_ALLOCA(cmd, max);
 	av2c_copy(argv, cmd, max);
@@ -87,14 +92,30 @@ int public_inbox_fork_exec(int in, int out, int err,
 	envp = AV_ALLOCA(env, max);
 	av2c_copy(envp, env, max);
 
+	ret = sigfillset(&set);
+	assert(ret == 0 && "BUG calling sigfillset");
+	ret = sigprocmask(SIG_SETMASK, &set, &old);
+	assert(ret == 0 && "BUG calling sigprocmask to block");
 	pid = vfork();
 	if (pid == 0) {
+		int sig;
+
 		REDIR(in, 0);
 		REDIR(out, 1);
 		REDIR(err, 2);
+		for (sig = 1; sig < NSIG; sig++)
+			signal(sig, SIG_DFL); /* ignore errors on signals */
+		/*
+		 * don't bother unblocking, we don't want signals
+		 * to the group taking out a subprocess
+		 */
 		execve(filename, argv, envp);
 		xerr("execve failed");
 	}
+	errnum = errno;
+	ret = sigprocmask(SIG_SETMASK, &old, NULL);
+	assert(ret == 0 && "BUG calling sigprocmask to restore");
+	errno = errnum;
 
 	return (int)pid;
 }
@@ -110,8 +131,10 @@ if (defined $vfork_spawn) {
 		my $f = "$inline_dir/.public-inbox.lock";
 		open my $fh, '>', $f or die "failed to open $f: $!\n";
 		flock($fh, LOCK_EX) or die "LOCK_EX failed on $f: $!\n";
-		eval 'use Inline C => $vfork_spawn';
+		eval 'use Inline C => $vfork_spawn'; #, BUILD_NOISY => 1';
+		my $err = $@;
 		flock($fh, LOCK_UN) or die "LOCK_UN failed on $f: $!\n";
+		die $err if $err;
 	};
 	if ($@) {
 		warn "Inline::C failed for vfork: $@\n";
@@ -125,6 +148,7 @@ unless (defined $vfork_spawn) {
 	*public_inbox_fork_exec = *PublicInbox::SpawnPP::public_inbox_fork_exec
 }
 
+# n.b. we never use absolute paths with this
 sub which ($) {
 	my ($file) = @_;
 	foreach my $p (split(':', $ENV{PATH})) {
@@ -158,23 +182,19 @@ sub spawn ($;$$) {
 	my $in = $opts->{0} || 0;
 	my $out = $opts->{1} || 1;
 	my $err = $opts->{2} || 2;
-	public_inbox_fork_exec($in, $out, $err, $f, $cmd, \@env);
+	my $pid = public_inbox_fork_exec($in, $out, $err, $f, $cmd, \@env);
+	$pid < 0 ? undef : $pid;
 }
 
 sub popen_rd {
 	my ($cmd, $env, $opts) = @_;
-	unless (wantarray || defined $vfork_spawn || defined $env) {
-		open my $fh, '-|', @$cmd or
-			die('open `'.join(' ', @$cmd) . " pipe failed: $!\n");
-		return $fh
-	}
 	pipe(my ($r, $w)) or die "pipe: $!\n";
 	$opts ||= {};
 	my $blocking = $opts->{Blocking};
-	$r->blocking($blocking) if defined $blocking;
+	IO::Handle::blocking($r, $blocking) if defined $blocking;
 	$opts->{1} = fileno($w);
 	my $pid = spawn($cmd, $env, $opts);
-	close $w;
+	return unless defined $pid;
 	return ($r, $pid) if wantarray;
 	my $ret = gensym;
 	tie *$ret, 'PublicInbox::ProcessPipe', $pid, $r;