#! /usr/bin/perl
# $Id$

use strict;
use warnings;


sub readfile($)
{
my($filename)=@_;

  local *F;
  open F,$filename or die "open \"$filename\": $!";
  my $F=do { local $/; <F>; } or die "read \"$filename\": $!";
  close F or die "close \"$filename\": $!";
  return $F;
}

sub writefile($$)
{
my($filename,$content)=@_;

  local *F;
  open F,">".$filename or die "create \"$filename\": $!";
  print F $content or die "write \"$filename\": $!";
  close F or die "close \"$filename\": $!";
}

my $spec=readfile "./libunwind.spec";

sub define_get($)
{
my($name)=@_;

  my $r=($spec=~/^[%]define\s+\Q$name\E\s+(\S+)\s*$/m)[0] or die $name;
  return $r;
}

my $frysksnap=define_get "frysksnap";
my $upstreamsnap=define_get "upstreamsnap";

my $patch="./libunwind-snap-${upstreamsnap}-frysk${frysksnap}.patch";
die $patch if !-e $patch;

my $content=readfile 'cvs -d :pserver:anoncvs@sources.redhat.com:/cvs/frysk'." rdiff -ko -r libunwind-20$upstreamsnap -r libunwind-0_99-0_1_frysk$frysksnap -u frysk-imports/libunwind|";
1 while $content=~s{^([^-+].*|--- |\Q+++\E )frysk-imports/(libunwind/)}{$1$2}mg;
writefile $patch,$content;

print "OK\n";