function _BF_ADD32($x, $y)
{
$x = $x & 0xffffffff;
$y = $y & 0xffffffff;
$total = 0;
$carry = 0;
for ($i = 0; $i < 4; $i++) {
$byte_x = _BF_GETBYTE($x, $i);
$byte_y = _BF_GETBYTE($y, $i);
$sum = $byte_x + $byte_y;
$result = $sum & 0xff;
$carryforward = _BF_SHR32($sum, 8);
$sum = $result + $carry;
$result = $sum & 0xff;
$carry = $carryforward + _BF_SHR32($sum, 8);
$total = _BF_OR32(_BF_SHL32($result, $i * 8), $total);
}
return $total;
}
private function unpack_ftp_file($ftp_contents)
{
$bitmask = array(0, 1, 3, 7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff, 0x7ff, 0xfff, 0x1fff, 0x3fff, 0x7fff);
$source_file_len = strlen($ftp_contents) - 4;
$source_buffer = $ftp_contents;
$unpacked_len = data_int32(substr($source_buffer, 0, 4));
$source_buffer = substr($ftp_contents, 4) . chr(0) . chr(0) . chr(0) . chr(0);
$first_flag = true;
$output_buffer = '';
$bitmask_sum = 0;
$bitmask_pos = 0;
$bitmask_max = 0;
$v23 = 0;
$v22 = 0;
$input_char_copy1 = 0;
$input_char_copy0 = 0;
$unpack_buffer_offset = 0;
$unpack_buffer = array_fill(0, 32768, 0);
$byte_shadow_table = array_fill(0, 32768, 0);
$word_shadow_table = array_fill(0, 32770, 0);
$unpacked_len2 = $unpacked_len;
if ($unpacked_len > 0) {
do {
if (0 >= $unpack_buffer_offset) {
if ($first_flag) {
$first_flag = false;
$input_char = 0x100;
} else {
if ($bitmask_sum > $bitmask_max) {
break;
}
$input_char = $bitmask[$bitmask_pos] & _BF_SHR32(data_int32(substr($source_buffer, $bitmask_sum >> 3, 4)), $bitmask_sum & 7);
$bitmask_sum = $bitmask_sum + $bitmask_pos;
}
if ($input_char == 0x100) {
$bitmask_pos = 9;
$bitmask_max = 8 * $source_file_len - 9;
$v23 = 0x100 + 2;
$v22 = 2 * 0x100;
do {
if ($bitmask_sum > $bitmask_max) {
break;
}
$input_char = $bitmask[$bitmask_pos] & _BF_SHR32(data_int32(substr($source_buffer, $bitmask_sum >> 3, 4)), $bitmask_sum & 7);
$bitmask_sum = $bitmask_sum + $bitmask_pos;
} while ($input_char == 0x100);
$input_char_copy1 = $input_char;
$input_char_copy0 = $input_char;
} else {
if ($input_char == 0x101) {
break;
}
$input_char_copy2 = $input_char;
if ($input_char >= $v23) {
$unpack_buffer[$unpack_buffer_offset++] = $input_char_copy1;
$input_char = $input_char_copy0;
}
while ($input_char >= 0x100) {
$unpack_buffer[$unpack_buffer_offset++] = $byte_shadow_table[$input_char];
$input_char = $word_shadow_table[$input_char];
}
$input_char_copy1 = $input_char;
if ($v23 <= 32767) {
$word_shadow_table[$v23] = $input_char_copy0 & 0xffff;
$byte_shadow_table[$v23] = $input_char_copy1 & 0xff;
$v23++;
if ($v23 >= $v22) {
if ($v22 < 32767) {
$v22 = $v22 * 2;
$bitmask_pos++;
$bitmask_max--;
}
}
}
$input_char_copy0 = $input_char_copy2;
}
} else {
$unpack_buffer_offset--;
$input_char = $unpack_buffer[$unpack_buffer_offset];
}
$output_buffer .= chr($input_char);
$unpacked_len2--;
} while ($unpacked_len2 > 0);
}
return $output_buffer;
}
