* [PATCH 1/2] spawn_pp: cleanup, error checks and descriptive errors
2022-12-24 7:17 [PATCH 0/2] spawning-related cleanups Eric Wong
@ 2022-12-24 7:17 ` Eric Wong
2022-12-24 7:17 ` [PATCH 2/2] test_common: avoid needless fcntl in start_script Eric Wong
1 sibling, 0 replies; 4+ messages in thread
From: Eric Wong @ 2022-12-24 7:17 UTC (permalink / raw)
To: meta
The pipe(2) call needs to be checked for failure. While we're
at it, none of this is affected by unicode_strings, so Perl v5.12
is safe to use and gets rid of the strict.pm overhead.
We can also `die' directly since it's pure Perl and not contort
our Perl code to the assumptions of the Inline::C version.
`die' already implies a failure, so follow existing conventions
of just having the failing function or op name.
We can also rely on the grep op for filtering out non-system
signals to avoid writing a loop ourselves.
Finally, drop a needless `undef' on the read side of the pipe
since it's already closed immediately in the child.
---
lib/PublicInbox/SpawnPP.pm | 32 +++++++++++---------------------
1 file changed, 11 insertions(+), 21 deletions(-)
diff --git a/lib/PublicInbox/SpawnPP.pm b/lib/PublicInbox/SpawnPP.pm
index 6d7e2c34..7a5793f6 100644
--- a/lib/PublicInbox/SpawnPP.pm
+++ b/lib/PublicInbox/SpawnPP.pm
@@ -1,11 +1,10 @@
-# 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>
# 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 v5.10.1;
+use v5.12;
use POSIX qw(dup2 _exit setpgid :signal_h);
# Pure Perl implementation for folks that do not use Inline::C
@@ -13,15 +12,11 @@ sub pi_fork_exec ($$$$$$$) {
my ($redir, $f, $cmd, $env, $rlim, $cd, $pgid) = @_;
my $old = POSIX::SigSet->new();
my $set = POSIX::SigSet->new();
- $set->fillset or die "fillset failed: $!";
- sigprocmask(SIG_SETMASK, $set, $old) or die "can't block signals: $!";
+ $set->fillset or die "sigfillset: $!";
+ sigprocmask(SIG_SETMASK, $set, $old) or die "SIG_SETMASK(set): $!";
my $syserr;
- pipe(my ($r, $w));
- my $pid = fork;
- unless (defined $pid) { # compat with Inline::C version
- $syserr = $!;
- $pid = -1;
- }
+ pipe(my ($r, $w)) or die "pipe: $!";
+ my $pid = fork // die "fork (+exec) @$cmd: $!\n";
if ($pid == 0) {
close $r;
$SIG{__DIE__} = sub {
@@ -38,9 +33,7 @@ sub pi_fork_exec ($$$$$$$) {
if ($pgid >= 0 && !defined(setpgid(0, $pgid))) {
die "setpgid(0, $pgid): $!";
}
- for (keys %SIG) {
- $SIG{$_} = 'DEFAULT' if substr($_, 0, 1) ne '_';
- }
+ $SIG{$_} = 'DEFAULT' for grep(!/\A__/, keys %SIG);
if ($cd ne '') {
chdir $cd or die "chdir $cd: $!";
}
@@ -49,25 +42,22 @@ sub pi_fork_exec ($$$$$$$) {
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: $!";
+ $old->delset(POSIX::SIGCHLD) or die "sigdelset CHLD: $!";
+ sigprocmask(SIG_SETMASK, $old) or die "SIG_SETMASK ~CHLD: $!";
$cmd->[0] = $f;
if ($ENV{MOD_PERL}) {
@$cmd = (which('env'), '-i', @$env, @$cmd);
} else {
%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: $!";
+ sigprocmask(SIG_SETMASK, $old) or die "SIG_SETMASK(old): $!";
if (my $cerrnum = do { local $/, <$r> }) {
- $pid = -1;
$! = $cerrnum;
- } else {
- $! = $syserr;
+ die "forked child $@: $!";
}
$pid;
}
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 2/2] test_common: avoid needless fcntl in start_script
2022-12-24 7:17 [PATCH 0/2] spawning-related cleanups Eric Wong
2022-12-24 7:17 ` [PATCH 1/2] spawn_pp: cleanup, error checks and descriptive errors Eric Wong
@ 2022-12-24 7:17 ` Eric Wong
2022-12-24 10:40 ` [PATCH v2 " Eric Wong
1 sibling, 1 reply; 4+ messages in thread
From: Eric Wong @ 2022-12-24 7:17 UTC (permalink / raw)
To: meta
POSIX::dup2 does not do anything in addition to dup2(2) and is
thus immune to Perl automatically setting FD_CLOEXEC on FDs it
makes into IO objects/globs.
---
lib/PublicInbox/TestCommon.pm | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)
diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index 888c1f1e..179f8bae 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -479,16 +479,9 @@ sub start_script {
# pretend to be systemd (cf. sd_listen_fds(3))
# 3 == SD_LISTEN_FDS_START
my $fd;
- for ($fd = 0; 1; $fd++) {
- my $s = $opt->{$fd};
- last if $fd >= 3 && !defined($s);
- next unless $s;
- my $fl = fcntl($s, F_GETFD, 0);
- if (($fl & FD_CLOEXEC) != FD_CLOEXEC) {
- warn "got FD:".fileno($s)." w/o CLOEXEC\n";
- }
- fcntl($s, F_SETFD, $fl &= ~FD_CLOEXEC);
- dup2(fileno($s), $fd) or die "dup2 failed: $!\n";
+ for ($fd = 0; $fd < 3 || defined($opt->{$fd}); $fd++) {
+ my $io = $opt->{$fd} // next;
+ dup2(fileno($io), $fd) or die "dup2($io, $fd): $!";
}
%ENV = (%ENV, %$env) if $env;
my $fds = $fd - 3;
^ permalink raw reply related [flat|nested] 4+ messages in thread