Chris@0: <?php
Chris@0: namespace GuzzleHttp\Psr7;
Chris@0: 
Chris@0: use Psr\Http\Message\StreamInterface;
Chris@0: 
Chris@0: /**
Chris@0:  * Uses PHP's zlib.inflate filter to inflate deflate or gzipped content.
Chris@0:  *
Chris@0:  * This stream decorator skips the first 10 bytes of the given stream to remove
Chris@0:  * the gzip header, converts the provided stream to a PHP stream resource,
Chris@0:  * then appends the zlib.inflate filter. The stream is then converted back
Chris@0:  * to a Guzzle stream resource to be used as a Guzzle stream.
Chris@0:  *
Chris@0:  * @link http://tools.ietf.org/html/rfc1952
Chris@0:  * @link http://php.net/manual/en/filters.compression.php
Chris@0:  */
Chris@0: class InflateStream implements StreamInterface
Chris@0: {
Chris@0:     use StreamDecoratorTrait;
Chris@0: 
Chris@0:     public function __construct(StreamInterface $stream)
Chris@0:     {
Chris@0:         // read the first 10 bytes, ie. gzip header
Chris@0:         $header = $stream->read(10);
Chris@0:         $filenameHeaderLength = $this->getLengthOfPossibleFilenameHeader($stream, $header);
Chris@0:         // Skip the header, that is 10 + length of filename + 1 (nil) bytes
Chris@0:         $stream = new LimitStream($stream, -1, 10 + $filenameHeaderLength);
Chris@0:         $resource = StreamWrapper::getResource($stream);
Chris@0:         stream_filter_append($resource, 'zlib.inflate', STREAM_FILTER_READ);
Chris@17:         $this->stream = $stream->isSeekable() ? new Stream($resource) : new NoSeekStream(new Stream($resource));
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * @param StreamInterface $stream
Chris@0:      * @param $header
Chris@0:      * @return int
Chris@0:      */
Chris@0:     private function getLengthOfPossibleFilenameHeader(StreamInterface $stream, $header)
Chris@0:     {
Chris@0:         $filename_header_length = 0;
Chris@0: 
Chris@0:         if (substr(bin2hex($header), 6, 2) === '08') {
Chris@0:             // we have a filename, read until nil
Chris@0:             $filename_header_length = 1;
Chris@0:             while ($stream->read(1) !== chr(0)) {
Chris@0:                 $filename_header_length++;
Chris@0:             }
Chris@0:         }
Chris@0: 
Chris@0:         return $filename_header_length;
Chris@0:     }
Chris@0: }