BUG #1950: Subroutine info cached in pl/perl

The following bug has been logged online:

Bug reference:      1950
Logged by:          Greg Sabino Mullane
Email address:      greg@turnstep.com
PostgreSQL version: 8.0 and cvs
Operating system:   Linux
Description:        Subroutine info cached in pl/perl
Details:

Inner subroutines seem to be caching initial values (e.g. the all important
%_TD hash)


\o /dev/null
CREATE TEMP TABLE event_problem (a int);
CREATE OR REPLACE FUNCTION event_problem() RETURNS TRIGGER LANGUAGE plperlu
AS
$$

  my $event = $_TD->{event};
  elog(INFO, "Top event    : $event");
  my $newname = $_TD->{new}{a};
  elog(INFO, "Top newname  : $newname");
  &subber($event);

  sub subber {
    my $arg = shift;
    elog(INFO, join " | " => caller(0));
    elog(INFO, join " | " => caller(1));
    elog(INFO, "Sub info     : $info");
    elog(INFO, "Sub global   : $event");
    elog(INFO, "Sub direct   : $_TD->{event}");
    my $newname = $_TD->{new}{a};
    elog(INFO, "Sub newname  : $newname");
  }

  elog(INFO, "Bottom event : $event");
  return;
$$;

CREATE TRIGGER event_problem BEFORE INSERT ON event_problem
FOR EACH ROW EXECUTE PROCEDURE event_problem();

CREATE TRIGGER event_problem2 BEFORE UPDATE ON event_problem
FOR EACH ROW EXECUTE PROCEDURE event_problem();

-- Also happens with a single BEFORE UPDATE OR INSERT

\o
INSERT INTO event_problem(a) VALUES (22);
UPDATE event_problem SET a = 33;
INSERT INTO event_problem(a) VALUES (44);
UPDATE event_problem SET a = 55;


Outputs:

INFO:  Top event    : INSERT
INFO:  Top newname  : 22
INFO:  main | (eval 1) | 8 | main::subber | 1 |  |  |  | 0 |
INFO:  main | -e | 0 | main::__ANON__ | 1 | 0 |  |  | 0 |
INFO:  Sub info     :
INFO:  Sub global   : INSERT
INFO:  Sub direct   : INSERT
INFO:  Sub newname  : 22
INFO:  Bottom event : INSERT
INSERT 0 1
INFO:  Top event    : UPDATE
INFO:  Top newname  : 33
INFO:  main | (eval 1) | 8 | main::subber | 1 |  |  |  | 0 |
INFO:  main | -e | 0 | main::__ANON__ | 1 | 0 |  |  | 0 |
INFO:  Sub info     :
INFO:  Sub global   : INSERT
INFO:  Sub direct   : INSERT
INFO:  Sub newname  : 22
INFO:  Bottom event : UPDATE
UPDATE 1
INFO:  Top event    : INSERT
INFO:  Top newname  : 44
INFO:  main | (eval 1) | 8 | main::subber | 1 |  |  |  | 0 |
INFO:  main | -e | 0 | main::__ANON__ | 1 | 0 |  |  | 0 |
INFO:  Sub info     :
INFO:  Sub global   : INSERT
INFO:  Sub direct   : INSERT
INFO:  Sub newname  : 22
INFO:  Bottom event : INSERT
INSERT 0 1
INFO:  Top event    : UPDATE
INFO:  Top newname  : 55
INFO:  main | (eval 1) | 8 | main::subber | 1 |  |  |  | 0 |
INFO:  main | -e | 0 | main::__ANON__ | 1 | 0 |  |  | 0 |
INFO:  Sub info     :
INFO:  Sub global   : INSERT
INFO:  Sub direct   : INSERT
INFO:  Sub newname  : 22
INFO:  Bottom event : UPDATE
INFO:  Top event    : UPDATE
INFO:  Top newname  : 55
INFO:  main | (eval 1) | 8 | main::subber | 1 |  |  |  | 0 |
INFO:  main | -e | 0 | main::__ANON__ | 1 | 0 |  |  | 0 |
INFO:  Sub info     :
INFO:  Sub global   : INSERT
INFO:  Sub direct   : INSERT
INFO:  Sub newname  : 22
INFO:  Bottom event : UPDATE
UPDATE 2