#!/usr/bin/perl

# Copyright 2004 Dan Risacher (not that I'm proud of it, mind you) 
# May be used for any purpose so long as copyright remains in the source code 

use strict;

my $MOUNT = "/mnt/initrd";
my $IMAGE = "initrd.img";
my $SOURCE = "template";
my %progs;
my %libs;

&doit ("umount $MOUNT");
&doit ("dd if=/dev/zero of=$IMAGE bs=1024 count=20000");
&doit ("mke2fs -F $IMAGE");
&doit ("mount -o loop $IMAGE $MOUNT");
&doit ("cd $SOURCE; cp -rp . $MOUNT");
&read_proglist;
&copy_progs;
&doit ("umount $MOUNT");
&doit ("gzip -9 <$IMAGE >$IMAGE.gz");


sub read_proglist {
    open PROGRAMS, "programs.txt";
    while (my $line = <PROGRAMS>) {
	$line =~ s/\#.*//;
	if ($line =~ m/^\s*(\S+)/) {
	    if (-x $1) {
		my $ldd = `ldd $1`;
#		print "$1\n"; 
		$progs{$1} = 1;
#		print $ldd;
		while ($ldd =~ s/ \=\> (\S+)//) {
#		    print "	$1\n";
		    $libs{$1} = 1;
		}
	    }
	}
    }
}


sub copy_progs {
    for my $f (keys %progs) {
	&doit( "cp -p $f $MOUNT/$f");
    }
    for my $f (keys %libs) {
	$f =~ m!(\S*\/)!;	# match parent directory
	if (! -e "$MOUNT/$1") {
	    &doit( "mkdir -p  $MOUNT/$1");
	}
	print "$f\n";
	&doit( "cp -p $f $MOUNT/$f");
    }
}

sub doit {
    print @_, "\n";
    system @_;
}