lwes-perl-journal-listener

   1 #!/usr/bin/env perl
   2
   3 use strict;
   4 use warnings;
   5
   6 use Getopt::Long;
   7 use Pod::Usage;
   8 use LWES::EventParser;
   9 use LWES::Listener;
  10
  11 my $help_opt         = 0;
  12 my $man_opt          = 0;
  13 my $verbose_opt      = 0;
  14
  15 GetOptions
  16   (
  17     'help'           => \$help_opt,
  18     'man'            => \$man_opt,
  19     'verbose'        => \$verbose_opt,
  20   ) or pod2usage (2);
  21
  22 pod2usage (-exitval => -1, -verbose => 0) if $help_opt;
  23 pod2usage (-exitval => -2, -verbose => 2) if $man_opt;
  24
  25 my $listener_or_code;
  26
  27 # if the first argument is a file, we'll assume it s a journal file, and
  28 # use the PrintingListener
  29 if (-f $ARGV[0])
  30   {
  31     $listener_or_code = "LWES::Listeners::EventPrintingListener";
  32   }
  33 else
  34   {
  35     $listener_or_code = shift @ARGV;
  36   }
  37
  38 # determine the callback which will process each event
  39 my $processEventFunc = getProcessEventFunc ($listener_or_code, @ARGV);
  40
  41 foreach my $journal (@ARGV)
  42   {
  43     if (-f $journal)
  44       {
  45         open FH, "zcat $journal |";
  46
  47         # read and parse header
  48         my $header_bytes;
  49         while ( read (FH, $header_bytes, 22) == 22)
  50           {
  51             my $header = bytesToHeader ($header_bytes);
  52
  53             # read and parse bytes
  54             my $event_bytes;
  55             my $n = read (FH, $event_bytes, $header->{'PayloadLength'});
  56             if (defined ($n) && $n == $header->{'PayloadLength'})
  57               {
  58                 my $event = bytesToEvent ($event_bytes);
  59
  60                 # merge header into event
  61                 foreach my $h (keys %{$header})
  62                   {
  63                     unless (exists ($event->{$h}))
  64                       {
  65                         $event->{$h} = $header->{$h};
  66                       }
  67                   }
  68
  69                 # call handler
  70                 $processEventFunc->($event);
  71               }
  72             else
  73               {
  74                 die "malformed or truncated journal";
  75               }
  76           }
  77
  78         close FH;
  79       }
  80   }
  81
  82 0;