InflateStream.php in Auth0 Single Sign On 8.2

Namespace

GuzzleHttp\Psr7

File

vendor/guzzlehttp/psr7/src/InflateStream.php

<?php

namespace GuzzleHttp\Psr7;

use Psr\Http\Message\StreamInterface;

/**
 * Uses PHP's zlib.inflate filter to inflate deflate or gzipped content.
 *
 * This stream decorator skips the first 10 bytes of the given stream to remove
 * the gzip header, converts the provided stream to a PHP stream resource,
 * then appends the zlib.inflate filter. The stream is then converted back
 * to a Guzzle stream resource to be used as a Guzzle stream.
 *
 * @link http://tools.ietf.org/html/rfc1952
 * @link http://php.net/manual/en/filters.compression.php
 */
class InflateStream implements StreamInterface {
  use StreamDecoratorTrait;
  public function __construct(StreamInterface $stream) {

    // read the first 10 bytes, ie. gzip header
    $header = $stream
      ->read(10);
    $filenameHeaderLength = $this
      ->getLengthOfPossibleFilenameHeader($stream, $header);

    // Skip the header, that is 10 + length of filename + 1 (nil) bytes
    $stream = new LimitStream($stream, -1, 10 + $filenameHeaderLength);
    $resource = StreamWrapper::getResource($stream);
    stream_filter_append($resource, 'zlib.inflate', STREAM_FILTER_READ);
    $this->stream = $stream
      ->isSeekable() ? new Stream($resource) : new NoSeekStream(new Stream($resource));
  }

  /**
   * @param StreamInterface $stream
   * @param $header
   * @return int
   */
  private function getLengthOfPossibleFilenameHeader(StreamInterface $stream, $header) {
    $filename_header_length = 0;
    if (substr(bin2hex($header), 6, 2) === '08') {

      // we have a filename, read until nil
      $filename_header_length = 1;
      while ($stream
        ->read(1) !== chr(0)) {
        $filename_header_length++;
      }
    }
    return $filename_header_length;
  }

}

Classes

Name	Description
InflateStream	Uses PHP's zlib.inflate filter to inflate deflate or gzipped content.