PclZip::privReadEndCentralDir() –

You appear to be a bot. Output may be restricted

Description

Usage

PclZip::privReadEndCentralDir( $p_central_dir );

Parameters

$p_central_dir
( mixed ) required

Returns

void

Source

File name: wordpress/wp-admin/includes/class-pclzip.php
Lines:

1 to 100 of 149
  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) != $v_size)
    {
      // ----- Error log
      PclZip::PclZip::PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to go to the end of the archive \''.$this->zipname.'\'');

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

        // ----- Return
        return PclZip::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'] == 0x06054b50) {
        $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-$v_maximum_size))
      {
        // ----- Error log
        PclZip::PclZip::PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to seek back to the middle of the archive \''.$this->zipname.'\'');

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

      // ----- Read byte per byte in order to find the signature
      $v_pos = ftell($this->zip_fd);
      $v_bytes = 0x00000000;
      while ($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::PclZip::privErrorLog(PCLZIP_ERR_BAD_FORMAT, "Unable to find End of Central Dir Record signature");

        // ----- Return
        return PclZip::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)
    {

 

 View on GitHub View on Trac