Stream.php

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<?php
namespace TYPO3\CMS\Core\Http;

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

use Psr\Http\Message\StreamInterface;

class Stream implements StreamInterface
{
    protected $resource;

    protected $stream;

    public function __construct($stream, $mode = 'r')
    {
        $this->stream = $stream;
        if (is_resource($stream)) {
            $this->resource = $stream;
        } elseif (is_string($stream)) {
            $this->resource = fopen($stream, $mode);
        } else {
            throw new \InvalidArgumentException('Invalid stream provided; must be a string stream identifier or resource', 1436717284);
        }
    }

    public function __toString()
    {
        if (!$this->isReadable()) {
            return '';
        }
        try {
            $this->rewind();
            return $this->getContents();
        } catch (\RuntimeException $e) {
            return '';
        }
    }

    public function close()
    {
        if (!$this->resource) {
            return;
        }
        $resource = $this->detach();
        fclose($resource);
    }

    public function detach()
    {
        $resource = $this->resource;
        $this->resource = null;
        return $resource;
    }

    public function getSize()
    {
        if ($this->resource === null) {
            return null;
        }
        $stats = fstat($this->resource);
        return $stats['size'];
    }

    public function tell()
    {
        if (!$this->resource) {
            throw new \RuntimeException('No resource available; cannot tell position', 1436717285);
        }
        $result = ftell($this->resource);
        if (!is_int($result)) {
            throw new \RuntimeException('Error occurred during tell operation', 1436717286);
        }
        return $result;
    }

    public function eof()
    {
        if (!$this->resource) {
            return true;
        }
        return feof($this->resource);
    }

    public function isSeekable()
    {
        if (!$this->resource) {
            return false;
        }
        return (bool)$this->getMetadata('seekable');
    }

    public function seek($offset, $whence = SEEK_SET)
    {
        if (!$this->resource) {
            throw new \RuntimeException('No resource available; cannot seek position', 1436717287);
        }

        if (!$this->isSeekable()) {
            throw new \RuntimeException('Stream is not seekable', 1436717288);
        }
        $result = fseek($this->resource, $offset, $whence);
        if ($result !== 0) {
            throw new \RuntimeException('Error seeking within stream', 1436717289);
        }
    }

    public function rewind()
    {
        $this->seek(0);
    }

    public function isWritable()
    {
        if (!$this->resource) {
            return false;
        }
        $uri = $this->getMetadata('uri');
        return is_writable($uri);
    }

    public function write($string)
    {
        if (!$this->resource) {
            throw new \RuntimeException('No resource available; cannot write', 1436717290);
        }
        $result = fwrite($this->resource, $string);
        if ($result === false) {
            throw new \RuntimeException('Error writing to stream', 1436717291);
        }
        return $result;
    }

    public function isReadable()
    {
        if (!$this->resource) {
            return false;
        }
        $mode = $this->getMetadata('mode');
        return (strpos($mode, 'r') !== false || strpos($mode, '+') !== false);
    }

    public function read($length)
    {
        if (!$this->resource) {
            throw new \RuntimeException('No resource available; cannot read', 1436717292);
        }
        if (!$this->isReadable()) {
            throw new \RuntimeException('Stream is not readable', 1436717293);
        }
        $result = fread($this->resource, $length);
        if ($result === false) {
            throw new \RuntimeException('Error reading stream', 1436717294);
        }
        return $result;
    }

    public function getContents()
    {
        if (!$this->isReadable()) {
            return '';
        }
        $result = stream_get_contents($this->resource);
        if ($result === false) {
            throw new \RuntimeException('Error reading from stream', 1436717295);
        }
        return $result;
    }

    public function getMetadata($key = null)
    {
        $metadata = stream_get_meta_data($this->resource);
        if ($key === null) {
            return $metadata;
        }
        if (!isset($metadata[$key])) {
            return null;
        }
        return $metadata[$key];
    }

    public function attach($resource, $mode = 'r')
    {
        $error = null;
        if (!is_resource($resource) && is_string($resource)) {
            set_error_handler(function ($e) use (&$error) {
                $error = $e;
            }, E_WARNING);
            $resource = fopen($resource, $mode);
            restore_error_handler();
        }
        if ($error) {
            throw new \InvalidArgumentException('Invalid stream reference provided', 1436717296);
        }
        if (!is_resource($resource)) {
            throw new \InvalidArgumentException('Invalid stream provided; must be a string stream identifier or resource', 1436717297);
        }
        $this->resource = $resource;
    }
}