#!/usr/bin/perl
use warnings;
use strict;
use HTML::Entities;
sub end_of_diff() { /^<[^b]/ }
while (<>) {
    if (/^diff / .. end_of_diff() and not end_of_diff()) {
	print "\n" if /^[-+@ ]/;
	chomp;
	s/<br.*$//;
	decode_entities($_);
	print;
    }
}
print "\n";