PgCommon.pm: Dump netstat info when ports are in use and debug is on

PgCommon.pm

@@ -5,7 +5,7 @@ PgCommon - Common functions for the postgresql-common framework
 =head1 COPYRIGHT AND LICENSE
 
  (C) 2008-2009 Martin Pitt <mpitt@debian.org>
- (C) 2012-2021 Christoph Berg <myon@debian.org>
+ (C) 2012-2022 Christoph Berg <myon@debian.org>
 
 This program is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
@@ -1100,6 +1100,7 @@ sub next_free_port {
         # port in use by existing cluster
         if (exists $ports{$port}) {
             print "next_free_port: port $port in use on by existing cluster\n" if exists $ENV{DEBUG_NEXT_FREE_PORT};
+            system "ss --no-header -ap 'sport >= 5432 and sport <= 5439'" if exists $ENV{DEBUG_NEXT_FREE_PORT};
             next;
         }
 
@@ -1112,6 +1113,8 @@ sub next_free_port {
             close SOCK;
             unless ($res4) {
                 print "next_free_port: port $port in use on IPv4: $err\n" if exists $ENV{DEBUG_NEXT_FREE_PORT};
+                print "next_free_port: port $port in use on IPv4\n" if exists $ENV{DEBUG_NEXT_FREE_PORT};
+                system "ss --no-header -ap 'sport >= 5432 and sport <= 5439'" if exists $ENV{DEBUG_NEXT_FREE_PORT};
                 next;
             }
 	}
@@ -1125,6 +1128,7 @@ sub next_free_port {
                 close SOCK;
                 unless ($res6) {
                     print "next_free_port: port $port in use on IPv6: $err\n" if exists $ENV{DEBUG_NEXT_FREE_PORT};
+                    system "ss --no-header -ap 'sport >= 5432 and sport <= 5439'" if exists $ENV{DEBUG_NEXT_FREE_PORT};
                     next;
                 }
 	    }