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Message ID: 941     Entry time: 28 Nov 2013
Author: Konstantin Olchanski 
Topic: Info 
Subject: Audit of fixed size arrays 
In one of the experiments, we hit a long time bug in mdump - there was an array of 32 equipments and if 
there were more than 32 entries under /equipment, it would overrun and corrupt memory. Somehow this 
only showed up after mdump was switched to c++. The solution was to use std::vector instead of fixed 
size array.

Just in case, I checked other midas programs for fixed size arrays (other than fixed size strings) and found 
none. (in midas.c, there is a fixed size array of TR_FIFO[10], but code inspection shows that it cannot 
overrun).

I used this script. It can be modified to also identify any strange sized string arrays.

K.O.

#!/usr/bin/perl -w

while (1) {
  my $in = <STDIN>;
  last unless $in;
  #print $in;

  $in =~ s/^\s+//;

  next if $in =~ /^char/;
  next if $in =~ /^static char/;

  my $a = $in =~ /(.*)[(\d+)\]/;

  next unless $a;

  my $a1 = $1;
  my $a2 = $2;

  next if $a2 == 0;
  next if $a2 == 1;
  next if $a2 == 2;
  next if $a2 == 3;

  #print "[$a] [$a1] [$a2]\n";
  print "-> $a1[$a2]\n";
}

# end
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