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/LeiTag.pm b/lib/PublicInbox/LeiTag.pm
index 320b0355..da8caeb7 100644
--- a/lib/PublicInbox/LeiTag.pm
+++ b/lib/PublicInbox/LeiTag.pm
@@ -1,12 +1,12 @@
-# Copyright (C) 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>
 
 # handles "lei tag" command
 package PublicInbox::LeiTag;
-use strict;
-use v5.10.1;
+use v5.12;
 use parent qw(PublicInbox::IPC PublicInbox::LeiInput);
 use PublicInbox::InboxWritable qw(eml_from_path);
+use PublicInbox::OnDestroy;
 
 sub input_eml_cb { # used by PublicInbox::LeiInput::input_fh
         my ($self, $eml) = @_;
@@ -49,7 +49,7 @@ sub ipc_atfork_child {
         PublicInbox::LeiInput::input_only_atfork_child($self);
         $self->{lse} = $self->{lei}->{sto}->search;
         # this goes out-of-scope at worker process exit:
-        PublicInbox::OnDestroy->new($$, \&note_unimported, $self);
+        on_destroy \&note_unimported, $self;
 }
 
 # Workaround bash word-splitting s to ['kw', ':', 'keyword' ...]