--
-- File: logpck.pls
--
set serveroutput on
--
drop table ctl_trace ;
create table ctl_trace (id1 number(1) default 0 );
insert into ctl_trace values (0);
--
drop sequence logid_seq;
create  sequence logid_seq;

create or replace package glog as
  procedure log (p in varchar2);
  function chk_trace return boolean;
end;
/
show errors
create or replace package body glog as
  v_appinfo_mod varchar2(48);
  v_appinfo_act varchar2(32);
  procedure log (p in varchar2) is
   v_prefix varchar2(5) := chr(9) ;
   v_timestamp timestamp := systimestamp;
  begin
    dbms_application_info.read_module(v_appinfo_mod,v_appinfo_act);
    dbms_output.put_line(v_prefix || '..');
    dbms_output.put_line (v_prefix || '-----------------------');
    dbms_output.put_line (v_prefix || v_timestamp || ': Log Info => ' || p);
    dbms_output.put_line (v_prefix || v_appinfo_mod || ': ' || v_appinfo_act);
    dbms_output.put_line (v_prefix || '-----------------------');
  end log ;
  
  function chk_trace return boolean is
   v_retval number := 0 ;
   trace_on boolean := FALSE;
  begin
    select sign(id1)
    into v_retval
    from ctl_trace where rownum < 2;
    if v_retval = 0 then
      trace_on :=  false;
    else
      trace_on := true;
    end if;   
    return trace_on;
  end chk_trace ;
end;
/
show errors
--
create or replace package anwendung as
  procedure wichtig;
  procedure wichtig2;
end;
/
show errors
create or replace package body anwendung as
  trace_on boolean := FALSE;
  v_appinfo_mod varchar2(48);
  v_appinfo_act varchar2(32);
  procedure wichtig is
  begin
   trace_on := glog.chk_trace;
   v_appinfo_mod := 'wichtig';
   v_appinfo_act := 'erste Aktion';
   dbms_application_info.set_module(v_appinfo_mod,v_appinfo_act);
   dbms_output.put_line('Erste wichtige Aktion ...');
   if trace_on then
     glog.log('Loginfo ...');
   end if;
   v_appinfo_act := 'zweite Aktion';
   dbms_application_info.set_module(v_appinfo_mod,v_appinfo_act);
   dbms_output.put_line('Zweite  wichtige Aktion ...');
   if trace_on then
     glog.log('jetzt sind wir bei ZWEI');
   end if;
  end wichtig ;
  procedure wichtig2 is
  begin
   trace_on := glog.chk_trace;
   v_appinfo_mod := 'wichtig2';
   v_appinfo_act := 'erste Aktion';
   dbms_application_info.set_module(v_appinfo_mod,v_appinfo_act);
   dbms_output.put_line('wichtig2: Erste wichtige Aktion ...');
   if trace_on then
     glog.log('Loginfo ...');
   end if;
   v_appinfo_act := 'zweite Aktion';
   dbms_application_info.set_module(v_appinfo_mod,v_appinfo_act);
   dbms_output.put_line('wichtig2 Zweite  wichtige Aktion ...');
   if trace_on then
     glog.log('jetzt sind wir bei ZWEI');
   end if;
  end wichtig2 ;

end;
/
show errors