function PclZip::privReadEndCentralDir in Loft Data Grids 6.2

Same name and namespace in other branches

1. 7.2 vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php \PclZip::privReadEndCentralDir()

6 calls to PclZip::privReadEndCentralDir()

PclZip::privAdd in vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php

PclZip::privDeleteByRule in vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php

PclZip::privExtractByRule in vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php

PclZip::privList in vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php

PclZip::privMerge in vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php

... See full list

File

vendor/phpoffice/phpexcel/Classes/PHPExcel/Shared/PCLZip/pclzip.lib.php, line 4525

Class

PclZip

Code

function privReadEndCentralDir(&$p_central_dir) {
  $v_result = 1;

  // ----- Go to the end of the zip file
  $v_size = filesize($this->zipname);
  @fseek($this->zip_fd, $v_size);
  if (@ftell($this->zip_fd) != $v_size) {

    // ----- Error log
    PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to go to the end of the archive \'' . $this->zipname . '\'');

    // ----- Return
    return PclZip::errorCode();
  }

  // ----- First try : look if this is an archive with no commentaries (most of the time)
  // in this case the end of central dir is at 22 bytes of the file end
  $v_found = 0;
  if ($v_size > 26) {
    @fseek($this->zip_fd, $v_size - 22);
    if (($v_pos = @ftell($this->zip_fd)) != $v_size - 22) {

      // ----- Error log
      PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to seek back to the middle of the archive \'' . $this->zipname . '\'');

      // ----- Return
      return PclZip::errorCode();
    }

    // ----- Read for bytes
    $v_binary_data = @fread($this->zip_fd, 4);
    $v_data = @unpack('Vid', $v_binary_data);

    // ----- Check signature
    if ($v_data['id'] == 0x6054b50) {
      $v_found = 1;
    }
    $v_pos = ftell($this->zip_fd);
  }

  // ----- Go back to the maximum possible size of the Central Dir End Record
  if (!$v_found) {
    $v_maximum_size = 65557;

    // 0xFFFF + 22;
    if ($v_maximum_size > $v_size) {
      $v_maximum_size = $v_size;
    }
    @fseek($this->zip_fd, $v_size - $v_maximum_size);
    if (@ftell($this->zip_fd) != $v_size - $v_maximum_size) {

      // ----- Error log
      PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to seek back to the middle of the archive \'' . $this->zipname . '\'');

      // ----- Return
      return PclZip::errorCode();
    }

    // ----- Read byte per byte in order to find the signature
    $v_pos = ftell($this->zip_fd);
    $v_bytes = 0x0;
    while ($v_pos < $v_size) {

      // ----- Read a byte
      $v_byte = @fread($this->zip_fd, 1);

      // -----  Add the byte

      //$v_bytes = ($v_bytes << 8) | Ord($v_byte);

      // Note we mask the old value down such that once shifted we can never end up with more than a 32bit number
      // Otherwise on systems where we have 64bit integers the check below for the magic number will fail.
      $v_bytes = ($v_bytes & 0xffffff) << 8 | Ord($v_byte);

      // ----- Compare the bytes
      if ($v_bytes == 0x504b0506) {
        $v_pos++;
        break;
      }
      $v_pos++;
    }

    // ----- Look if not found end of central dir
    if ($v_pos == $v_size) {

      // ----- Error log
      PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, "Unable to find End of Central Dir Record signature");

      // ----- Return
      return PclZip::errorCode();
    }
  }

  // ----- Read the first 18 bytes of the header
  $v_binary_data = fread($this->zip_fd, 18);

  // ----- Look for invalid block size
  if (strlen($v_binary_data) != 18) {

    // ----- Error log
    PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, "Invalid End of Central Dir Record size : " . strlen($v_binary_data));

    // ----- Return
    return PclZip::errorCode();
  }

  // ----- Extract the values
  $v_data = unpack('vdisk/vdisk_start/vdisk_entries/ventries/Vsize/Voffset/vcomment_size', $v_binary_data);

  // ----- Check the global size
  if ($v_pos + $v_data['comment_size'] + 18 != $v_size) {

    // ----- Removed in release 2.2 see readme file
    // The check of the file size is a little too strict.
    // Some bugs where found when a zip is encrypted/decrypted with 'crypt'.
    // While decrypted, zip has training 0 bytes
    if (0) {

      // ----- Error log
      PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'The central dir is not at the end of the archive.' . ' Some trailing bytes exists after the archive.');

      // ----- Return
      return PclZip::errorCode();
    }
  }

  // ----- Get comment
  if ($v_data['comment_size'] != 0) {
    $p_central_dir['comment'] = fread($this->zip_fd, $v_data['comment_size']);
  }
  else {
    $p_central_dir['comment'] = '';
  }
  $p_central_dir['entries'] = $v_data['entries'];
  $p_central_dir['disk_entries'] = $v_data['disk_entries'];
  $p_central_dir['offset'] = $v_data['offset'];
  $p_central_dir['size'] = $v_data['size'];
  $p_central_dir['disk'] = $v_data['disk'];
  $p_central_dir['disk_start'] = $v_data['disk_start'];

  // TBC

  //for(reset($p_central_dir); $key = key($p_central_dir); next($p_central_dir)) {

  //}

  // ----- Return
  return $v_result;
}