Old record being clobbered inside a loop.

Hi, Background: bttrack.py is a open src torrent tracker, that uses
the option --dfile fileName, to save state information in. The file is
bencoded and has parts of it's content in binary. The encoding specs
and file format are described here:
http://wiki.theory.org/BitTorrentSpecification#lists

I am trying to write my own Perl script to create my own "dfile".

Data from a valid dstateFile (binary data has been converted to
ASCII):

d9:completedd20:.i.?.vk..&.7.....g..i0ee5:peersd20:.i.?.vk..&.
7.....g..
d20:-AZ2504-4PGqC1Tza6WDd2:ip9:127.0.0.13:key8:vkYZ3mwZ4:lefti12415246
5e3:nati0e4:porti35ee20:-
UT1740-..........#.d2:ip9:127.0.0.13:key8:29FA
43C64:lefti37137041e3:nati0e4:porti35eeeee

The above data when you interpret correctly (based on the
TorrentSpecs)forms a data structure like so:

{ 'completed' => { $shaHashBin => '0' }
'peers' => { $shaHashBin => { $clientID { ip => $ipAddr, key=>
$Key, left=>'0', nat=>'0', port=>$port}
$clientID2 { ip =>
$ipAddr, key=>$Key, left=>'0', nat=>'0', port=>$port}
}
}

}

Unfortunately for some reason $clientID is not being expanded properly
and instead of getting ClientID1/ClientID2/ClientID3 etc and their
associated ip/key/left/nat/port entries, all i get is a
single entry! I'm sure that the old records/entries are being
overwritten by the new entries - so I'm left with a perfectly valid
dstateFile with the last ip:port pair that was read from the file!

I also tried something like so:
$_=<IPFILE>;
chomp;
($ipAddr, $port) = split(/:/);

$clientID = RandomString(20);
$key = RandomString(8);

# dflist file structure.
<SNIP&gt;

while (<IPFILE>) {
chomp;
($ipAddr, $port) = split(/:/);

$clientID = RandomString(20);
$key = RandomString(8);

$completedData->{'peers'}->{$clientID} =
MakeClientHash($ipAddr, $key, $port);
}

This works and the records don't get overwritten BUT the file format
is broken and i get data like so: d9:completedd20:.i.?.vk..&.
7.....g..i0ee5:peersd20:.i.?.vk..&;.7.....g..d20:-AZ2504-4PGqC1Tza6WDd2:ip9:127.0.0.13:key8:vkYZ3mwZ4:lefti12415246
5e3:nati0e4:porti35eee20:-UT1740-..........#.d2:ip9:127.0.0.13:key8:29FA
43C64:lefti37137041e3:nati0e4:porti35eeee

Note the (eeee) That's }}}}. There should be 5 of them :( also note
eee20 - that should read ee20 :( Oh, and note: bencode breaks if the
torrentfile is complicated (just in case you actually debug
that).

----------------------------------------------------------
#!/usr/bin/perl
#
# Program to create a file called dflist that bttrack.py can
understand.
#use strict;
#use warnings;

use POSIX qw(strftime);

use Getopt::Std;
use URI::Escape 'uri_escape_utf8';
use Digest::SHA1 qw(sha1 sha1_hex sha1_base64);
use Convert::Bencode qw(bencode bdecode);

my ($torrentFile, $ipFile, $dflistFile);
my $debug=0;

(my $progname = $0) =~ s|.*/||;

sub UsageError() {
print STDERR "nusage: $progname torrentFile ipFile dfileNamen";
exit(2);

}

sub FatalError( $ ) {
print STDERR "$progname: _n";
exit(1);

}

sub GetRunConfig() {
# If we have more than two arguments signal a error.
UsageError if (ARGV != 3);

if (ARGV == 3) { $torrentFile = $ARGV[0];
$ipFile = $ARGV[1];
$dflistFile = $ARGV[2]; }

}

sub ReadFile( $ ) {
my ($pathname) = _;
local $/;
my $FH;
open($FH, '<', $pathname)
or FatalError("cannot open $pathname for reading: $!");
my $contents = <$FH>;;
close $FH;
return $contents;

}

sub WriteFile( $$ ) {
my $FH;
my ($pathname, $contents) = _;
open($FH, '>', $pathname)
or FatalError("cannot open $pathname for writing: $!");
# Required because we are writing binary data
binmode($FH);
print $FH $contents;
close($FH)
or FatalError("error writing to file $pathname: $!");

}

sub RandomString( $ ) {
my ($lenOfRanStr) = _;
my chars=('a'..'z','A'..'Z','0'..'9','_');
my $ranStr;

foreach (1..$lenOfRanStr) {
# rand chars will generate a random
# number between 0 and scalar chars
$ranStr .= $chars[rand chars];
}
return $ranStr;

}

sub MakeClientHash( $$$ ) {
my ($ipAddr, $key, $port) = _;
return { ip => $ipAddr,
key => $key,
left => '0',
nat => '0',
port => $port };

}

sub CreateDflist {
# Creates a dflist file based on the torrentfile and the
# ipaddress file you provide.
my ($contents, $contentsRef, $shaHashBin, $completedData);

# Read the supplied torrentfile, extract the info values, and compute
# the sha1 hash in binary form ($shaHashBin).
$contents = ReadFile($torrentFile);
$contentsRef = bdecode($contents);
$shaHashBin = sha1(bencode($contentsRef->{'info'}));
my ( $clientID, $ipAddr, $key, $port);

# Read $ipFile and get the $ipAddr:$port pairs for the $torrentFile.
open(IPFILE, $ipFile)
or die "can't open $ipFile: $!";

while(<IPFILE&gt;) {
chomp $_;
($ipAddr, $port) = split(/:/);

$clientID = RandomString(20);
$key = RandomString(8);

# dflist file structure.
$completedData = {
'completed' => { $shaHashBin => '0' },
'peers' => { $shaHashBin => {$clientID =>

MakeClientHash($ipAddr, $key, $port)} }
};
}

# Write dflist data after encoding.
my $encString = bencode($completedData);
WriteFile("$dflistFile&quot;, $encString);

print $encString;

}

GetRunConfig;
CreateDflist;

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Hi, resolved this.

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