#! /usr/local/bin/perl
# File: tftp-put
# Purpose: Ethernet downloader using UDP protocol
# Author: Phil Bunce (pjb@carmel.com)
# Revision History:
#	970503	Created
#	970508	Working!!
#	970508	Also working under Win95!
#	970512	Modified to read /windows/hosts
#	970715	Added tick
#	980330	Having probs with system hanging on win95 (2x ctl-alt-del
#		required). Tried adding select(), but that causes an instant 
#		reboot. The script works fine w or w/o select() on UNIX.
#	980330	Prob with hang and crash seems to be fixed. All I did was
#		comment out everything to do with flush.pl. I even added
#		a resend on timeout that seems to work.
#	980406	Added resend to open. Changed to use for instead of goto.
#	981207	Added die to gethostbyname
#	981207	Use windir to open /windows/hosts file.

# use strict;
# require 5.002;
# use Socket;
# use Carp;
# use Sys::Hostname;

#require "flush.pl";

if ($#ARGV != 1) {
	print "usage: tftp-put host file\n";
	exit 1;
	}

#@ticklst = ('|','/','-','\\');
#
#sub tick {
#	printflush(STDOUT,"\r $ticklst[$tickinx]");
#	$tickinx++;
#	if ($tickinx > $#ticklst) {$tickinx = 0;}
#}


# Dump a packed value
sub printPacked {
	local($value) = @_;
	local($i);

	for ($i=0;$i<length($value);$i++) {
		printf "%02x ", unpack("x$i C",$value);
		}
	print "\n";
	}

($them,$file) = @ARGV;

$AF_INET = 2; 		# from sys/socket.h
$SOCK_DGRAM = 2; 	# from sys/socket.h
$port = 69;
$socketaddr = 'S n a4 x8';

# hostname command does not exist on Win95
# so we search the HOSTS file for loghost
if ($windir=$ENV{'windir'}) {
	open(HF,"$windir/hosts");
	while (<HF>) {
		chomp;
		next if /^#/;
		next if ! /loghost/;
		($ip,$hostname,$junk) = split;
		}
	close(HF);
	}
else { chop($hostname = `hostname`);}
#print "hostname=$hostname\n";
print "sending $file from $hostname to $them via UDP\n";

($name,$aliases,$proto) = getprotobyname('udp');
#print "proto=$proto\n";

socket(S, $AF_INET, $SOCK_DGRAM, $proto)   || die "socket: $!";

($name,$aliases,$type,$len,@thisaddr) = gethostbyname($hostname) 
	|| die "gethostbyname: $!";
($a,$b,$c,$d) = unpack('C4', $thisaddr[0]);

#print "name=$name aliases=$aliases type=$type thisaddr=$a.$b.$c.$d\n";

$this = pack($socketaddr, $AF_INET, 0, $thisaddr[0]);
#&printPacked($this);

bind(S, $this) || die "bind fail: $!\n";

($name,$aliases,$type,$len,@thataddr) = gethostbyname($them);
($a,$b,$c,$d) = unpack('C4', $thataddr[0]);
#print("name=$name aliases=$aliases type=$type thataddr=$a.$b.$c.$d\n");

$that = pack($socketaddr, $AF_INET, $port, $thataddr[0]);
#&printPacked($that);

$x = length($file)+1;
$openhdr = pack("C2 a$x a9",0,2,$file,"netascii");
#&printPacked($openhdr);

$rin = "";
vec($rin,fileno(S),1) = 1;

for ($cnt=0;;$cnt++) {
	send(S, $openhdr, 0, $that) || die "send fail: $!\n";
	($nfound,$timeleft) = select($rout=$rin,undef,undef,3.0);
	last if $nfound != 0;
	if ($cnt > 3) {die "unable to contact $them: $!\n";}
	print "timeout. resending open...\n";
	}
$msg = "";
recv(S, $msg, 128, 0) || die "recv fail: $!\n";
	
open(IF,$file) || die "can't open $file\n";
while (<IF>) {
	$x = length($_);
	$msg = pack("C4 a$x",0,3,0,1,$_);
	for ($cnt=0;;$cnt++) {
		send(S, $msg, 0, $that) || die "send fail: $!\n";
		($nfound,$timeleft) = select($rout=$rin,undef,undef,3.0);
		last if $nfound != 0;
		if ($cnt > 3) {die "unable to contact $them: $!\n";}
		print "timeout. resending data...\n";
		}
	recv(S, $msg, 128, 0) || die "recv fail: $!\n";
	#&tick();
	}
close(IF);