treewide: avoid getpid() for OnDestroy checks

getpid() isn't cached by glibc nowadays and system calls are
more expensive due to CPU vulnerability mitigations.  To
ensure we switch to the new semantics properly, introduce
a new `on_destroy' function to simplify callers.
Furthermore, most OnDestroy correctness is often tied to the
process which creates it, so make the new API default to
guarded against running in subprocesses.

For cases which require running in all children, a new
PublicInbox::OnDestroy::all call is provided.

1 files changed, 4 insertions, 4 deletions

diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index 81f940fe..7c31ab43 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -9,7 +9,7 @@ package PublicInbox::LEI;
 use v5.12;
 use parent qw(PublicInbox::DS PublicInbox::LeiExternal
         PublicInbox::LeiQuery);
-use autodie qw(bind chdir fork open pipe socket socketpair syswrite unlink);
+use autodie qw(bind chdir open pipe socket socketpair syswrite unlink);
 use Getopt::Long ();
 use Socket qw(AF_UNIX SOCK_SEQPACKET pack_sockaddr_un);
 use Errno qw(EPIPE EAGAIN ECONNREFUSED ENOENT ECONNRESET);
@@ -24,6 +24,7 @@ use PublicInbox::Lock;
 use PublicInbox::Eml;
 use PublicInbox::Import;
 use PublicInbox::ContentHash qw(git_sha);
+use PublicInbox::OnDestroy;
 use PublicInbox::IPC;
 use Time::HiRes qw(stat); # ctime comparisons for config cache
 use File::Path ();
@@ -631,9 +632,8 @@ sub _delete_pkt_op { # OnDestroy callback to prevent leaks on die
 
 sub pkt_op_pair {
         my ($self) = @_;
-        require PublicInbox::OnDestroy;
         require PublicInbox::PktOp;
-        my $end = PublicInbox::OnDestroy->new($$, \&_delete_pkt_op, $self);
+        my $end = on_destroy \&_delete_pkt_op, $self;
         @$self{qw(pkt_op_c pkt_op_p)} = PublicInbox::PktOp->pair;
         $end;
 }
@@ -1357,7 +1357,7 @@ sub lazy_start {
         STDIN->autoflush(1);
         dump_and_clear_log();
         POSIX::setsid() > 0 or die "setsid: $!";
-        my $pid = fork;
+        my $pid = PublicInbox::OnDestroy::fork_tmp;
         return if $pid;
         $0 = "lei-daemon $path";
         local (%PATH2CFG, $MDIR2CFGPATH);