extract-xml.php

<?php

$start = memory_get_usage(true);

define('INPUT_FILE', $argv[1]);
define('IS_DECODE', array_search('--decode', $argv) !== false);

if (!is_file(INPUT_FILE)) {
  echo "Invalid or missing input.\n";
  echo "Usage: php extract-xml.php download.xml [--decode]\n";
  echo "Examples:\n";
  echo "  php extract-xml.php download.xml --decode ; unzip download.xml.zip\n";
  echo "  php extract-xml.php download.xml ; base64 --decode download.xml.base64 > download.final.zip\n";
  exit(1);
}

$f = fopen(INPUT_FILE, 'r');
$h = fread($f, 1024);
$i = strpos($h, '<Paquete>');
$o = fopen(INPUT_FILE . (IS_DECODE ? '.zip' : '.base64'), 'w');
$b = '';

function clean($value) {
  return trim(preg_replace('/ +/', '', $value));
}

if ($i !== false) {
  if (IS_DECODE) {
    $b .= clean(substr($h, $i + 9));
  } else {
    fwrite($o, clean(substr($h, $i + 9)));
  }
}

while (1) {
  $c = fread($f, 4096);
  $j = strpos($c, '</Paquete>');

  if ($j !== false) {
    if (IS_DECODE) {
      $b .= clean(substr($c, 0, $j));
    } else {
      fwrite($o, clean(substr($c, 0, $j)));
    }
    break;
  }

  if (IS_DECODE) {
    $b .= clean($c);
  } else {
    fwrite($o, clean($c));
  }
  $x++;
}

if (IS_DECODE) {
  fwrite($o, base64_decode($b));
}

fclose($f);
fclose($o);

$end = memory_get_usage(true);
$size = $end - $start;

$unit = ['B', 'KB', 'MB', 'GB', 'TB', 'PB'];

if ($size) {
  echo @round($size / pow(1024, ($i = floor(log($size, 1024)))), 2) . ' ' . $unit[$i];
}