1st

combine-saves.pl

@@ -0,0 +1,54 @@
+#!/usr/bin/perl -p
+#
+# save-combine - filter and combine output from ipset(1) save
+#
+# (c)2026 Corwin Brust <corwin@bru.st>
+#
+# You may use this program under the terms of the GNU Public License version three (3) or, at your option, any later version of that license. (GPLv3+)
+#
+# Use a flat-file "DB" of ipset per row in the form NAME MAX
+# Drop create/add lines for any set not mentioned in the DB
+# Take DB file-name from first program arg, otherwise "ipset-counts.txt"
+# Input is expected on stdin in the same format as output by ipset save
+#
+
+sub max2 {
+  my $val = $_[0] || 1;
+  my $rv = 2;
+  $rv *= 2 until $rv > $val;
+  return $rv;
+}
+
+BEGIN {
+	my $SET_COUNTS = @ARGV ? shift : q(max-counts.txt);
+       	open my$FH,q(<),$SET_COUNTS or die $!;
+	while(<$FH>) {
+		chomp;
+		my($k,$v)=split;
+		$m{$k}=max2( $v ) if $k and $v
+	}
+}
+
+if(/^create (\S+)/) {
+	if(exists $h{$1}) {
+		$_ = '';
+	} elsif(exists $m{$1}) {
+		$h{$1} = 1; # don't reissue creates
+		$n = $1; # grab the name
+		$v = $m{$n}; # lookup max
+		s/^create $n (.*?maxelem) \d+ (.*)$/create $n $1 $v $2/
+		    and warn qq[set $n=$v]
+	}
+	else {
+		$_ = ''; # skip create when no max defined
+	}
+}
+elsif(/^add (\S+)/)
+{
+    # $_ = '' unless exists $m{$1};
+    if (exists $m{$1}) {
+	s/$/ -exist/; # make dup-safe
+    } else {
+	$_ = '';
+    }
+}