From: Eric Wong <e@80x24.org>
Date: Thu, 27 Mar 2025 23:20:46 +0000 (+0000)
Subject: nntp: avoid repeated rand() calls
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5f6a55088d76f94987116cad6c355e86b553e68f;p=thirdparty%2Fpublic-inbox.git

nntp: avoid repeated rand() calls

We only need to generate the secret salt once, so initialize
it early to avoid potentially expensive `rand' ops in repeated
calls to wildmat2re.  We'll also stringify it early to hopefully
improve CoW sharing and reduce fragmentation.
---

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index eab6d301d..07d86d603 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -19,6 +19,7 @@ use PublicInbox::SHA qw(sha1_hex);
 use Time::Local qw(timegm timelocal);
 use PublicInbox::GitAsyncCat;
 use PublicInbox::Address;
+my $SALT = rand . ''; # stringify early for CoW sharing
 
 use constant {
 	LINE_MAX => 512, # RFC 977 section 2.3
@@ -278,11 +279,10 @@ sub wildmat2re ($) {
 	my $tmp = $_[0] // '*';
 	return qr/.*/ if $tmp eq '*';
 	my %keep;
-	my $salt = rand;
 
 	$tmp =~ s#(?<!\\)\[(.+)(?<!\\)\]#
 		my $orig = $1;
-		my $key = sha1_hex($orig . $salt);
+		my $key = sha1_hex($orig . $SALT);
 		$orig =~ s/([^\w\-])+/\Q$1/g;
 		$keep{$key} = $orig;
 		$key