#!/usr/perl5/bin/perl

# Copyright (C) 1997,1998,1999, Roger Espel Llima
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and any associated documentation files (the "Software"), to 
# deal in the Software without restriction, including without limitation the 
# rights to use, copy, modify, merge, publish, distribute, sublicense, 
# and/or sell copies of the Software, and to permit persons to whom the 
# Software is furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
# SOFTWARE'S COPYRIGHT HOLDER(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE

# (whew, that's done!)

# why does the world need another rpm2cpio?  because the existing one
# won't build unless you have half a ton of things that aren't really
# required for it, since it uses the same library used to extract RPM's.
# in particular, it won't build on the HPsUX box i'm on.


# add a path if desired
$gzip = "gzip";

sub printhelp {
  print <<HERE;
rpm2cpio, perl version by orabidoo <odar\@pobox.com>
dumps the contents to stdout as a cpio archive

use: rpm2cpio [file.rpm] > file.cpio

Here's how to use cpio:
     list of contents:   cpio -t -i < /file/name
        extract files:   cpio -d -i < /file/name
HERE

  exit 0;
}

if ($#ARGV == -1) {
  printhelp if -t STDIN;
  $f = "STDIN";
} elsif ($#ARGV == 0) {
  open(F, "< $ARGV[0]") or die "Can't read file $ARGV[0]\n";
  $f = 'F';
} else {
  printhelp;
}

printhelp if -t STDOUT;

# gobble the file up
undef $/;
$|=1;
$rpm = <$f>;
close ($f);

($magic, $major, $minor, $crap) = unpack("NCC C90", $rpm);

die "Not an RPM\n" if $magic != 0xedabeedb;
die "Not a version 3 or 4 RPM\n" if $major != 3 && $major != 4;

$rpm = substr($rpm, 96);

while ($rpm ne '') {
  $rpm =~ s/^\c@*//s;
  ($magic, $crap, $sections, $bytes) = unpack("N4", $rpm);
  $smagic = unpack("n", $rpm);
  last if $smagic eq 0x1f8b;
  die "Error: header not recognized\n" if $magic != 0x8eade801;
  $rpm = substr($rpm, 16*(1+$sections) + $bytes);
}

die "bogus RPM\n" if $rpm eq '';

open(ZCAT, "|gzip -cd") || die "can't pipe to gzip\n";
print STDERR "CPIO archive found!\n";

print ZCAT $rpm;
close ZCAT;