HTTPFileStreamer::stream()   F
last analyzed

Complexity

Conditions 22
Paths 461

Size

Total Lines 107
Code Lines 69

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
cc 22
eloc 69
nc 461
nop 4
dl 0
loc 107
rs 3.2645
c 0
b 0
f 0

How to fix   Long Method    Complexity   

Long Method

Small methods make your code easier to understand, in particular if combined with a good name. Besides, if your method is small, finding a good name is usually much easier.

For example, if you find yourself adding comments to a method's body, this is usually a good sign to extract the commented part to a new method, and use the comment as a starting point when coming up with a good name for this new method.

Commonly applied refactorings include:

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<?php
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/**
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 * Functions related to the output of file content.
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License along
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 * with this program; if not, write to the Free Software Foundation, Inc.,
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 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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 * http://www.gnu.org/copyleft/gpl.html
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 *
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 * @file
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 */
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/**
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 * Functions related to the output of file content
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 *
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 * @since 1.28
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 */
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class HTTPFileStreamer {
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	/** @var string */
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	protected $path;
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	/** @var callable */
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	protected $obResetFunc;
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	/** @var callable */
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	protected $streamMimeFunc;
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	// Do not send any HTTP headers unless requested by caller (e.g. body only)
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	const STREAM_HEADLESS = 1;
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	// Do not try to tear down any PHP output buffers
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	const STREAM_ALLOW_OB = 2;
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	/**
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	 * @param string $path Local filesystem path to a file
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	 * @param array $params Options map, which includes:
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	 *   - obResetFunc : alternative callback to clear the output buffer
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	 *   - streamMimeFunc : alternative method to determine the content type from the path
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	 */
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	public function __construct( $path, array $params = [] ) {
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		$this->path = $path;
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		$this->obResetFunc = isset( $params['obResetFunc'] )
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			? $params['obResetFunc']
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			: [ __CLASS__, 'resetOutputBuffers' ];
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		$this->streamMimeFunc = isset( $params['streamMimeFunc'] )
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			? $params['streamMimeFunc']
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			: [ __CLASS__, 'contentTypeFromPath' ];
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	}
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	/**
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	 * Stream a file to the browser, adding all the headings and fun stuff.
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	 * Headers sent include: Content-type, Content-Length, Last-Modified,
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	 * and Content-Disposition.
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	 *
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	 * @param array $headers Any additional headers to send if the file exists
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	 * @param bool $sendErrors Send error messages if errors occur (like 404)
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	 * @param array $optHeaders HTTP request header map (e.g. "range") (use lowercase keys)
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	 * @param integer $flags Bitfield of STREAM_* constants
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	 * @throws MWException
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	 * @return bool Success
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	 */
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	public function stream(
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		$headers = [], $sendErrors = true, $optHeaders = [], $flags = 0
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	) {
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		// Don't stream it out as text/html if there was a PHP error
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		if ( ( ( $flags & self::STREAM_HEADLESS ) == 0 || $headers ) && headers_sent() ) {
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			echo "Headers already sent, terminating.\n";
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			return false;
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		}
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		$headerFunc = ( $flags & self::STREAM_HEADLESS )
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			? function ( $header ) {
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				// no-op
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			}
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			: function ( $header ) {
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				is_int( $header ) ? HttpStatus::header( $header ) : header( $header );
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			};
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		MediaWiki\suppressWarnings();
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		$info = stat( $this->path );
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		MediaWiki\restoreWarnings();
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		if ( !is_array( $info ) ) {
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			if ( $sendErrors ) {
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				self::send404Message( $this->path, $flags );
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			}
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			return false;
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		}
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		// Send Last-Modified HTTP header for client-side caching
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		$mtimeCT = new ConvertibleTimestamp( $info['mtime'] );
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		$headerFunc( 'Last-Modified: ' . $mtimeCT->getTimestamp( TS_RFC2822 ) );
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		if ( ( $flags & self::STREAM_ALLOW_OB ) == 0 ) {
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			call_user_func( $this->obResetFunc );
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		}
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		$type = call_user_func( $this->streamMimeFunc, $this->path );
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		if ( $type && $type != 'unknown/unknown' ) {
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			$headerFunc( "Content-type: $type" );
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		} else {
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			// Send a content type which is not known to Internet Explorer, to
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			// avoid triggering IE's content type detection. Sending a standard
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			// unknown content type here essentially gives IE license to apply
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			// whatever content type it likes.
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			$headerFunc( 'Content-type: application/x-wiki' );
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		}
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		// Don't send if client has up to date cache
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		if ( isset( $optHeaders['if-modified-since'] ) ) {
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			$modsince = preg_replace( '/;.*$/', '', $optHeaders['if-modified-since'] );
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			if ( $mtimeCT->getTimestamp( TS_UNIX ) <= strtotime( $modsince ) ) {
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				ini_set( 'zlib.output_compression', 0 );
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				$headerFunc( 304 );
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				return true; // ok
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			}
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		}
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		// Send additional headers
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		foreach ( $headers as $header ) {
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			header( $header ); // always use header(); specifically requested
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		}
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		if ( isset( $optHeaders['range'] ) ) {
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			$range = self::parseRange( $optHeaders['range'], $info['size'] );
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			if ( is_array( $range ) ) {
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				$headerFunc( 206 );
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				$headerFunc( 'Content-Length: ' . $range[2] );
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				$headerFunc( "Content-Range: bytes {$range[0]}-{$range[1]}/{$info['size']}" );
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			} elseif ( $range === 'invalid' ) {
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				if ( $sendErrors ) {
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					$headerFunc( 416 );
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					$headerFunc( 'Cache-Control: no-cache' );
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					$headerFunc( 'Content-Type: text/html; charset=utf-8' );
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					$headerFunc( 'Content-Range: bytes */' . $info['size'] );
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				}
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				return false;
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			} else { // unsupported Range request (e.g. multiple ranges)
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				$range = null;
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				$headerFunc( 'Content-Length: ' . $info['size'] );
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			}
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		} else {
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			$range = null;
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			$headerFunc( 'Content-Length: ' . $info['size'] );
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		}
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		if ( is_array( $range ) ) {
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			$handle = fopen( $this->path, 'rb' );
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			if ( $handle ) {
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				$ok = true;
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				fseek( $handle, $range[0] );
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				$remaining = $range[2];
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				while ( $remaining > 0 && $ok ) {
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					$bytes = min( $remaining, 8 * 1024 );
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					$data = fread( $handle, $bytes );
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					$remaining -= $bytes;
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					$ok = ( $data !== false );
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					print $data;
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				}
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			} else {
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				return false;
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			}
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		} else {
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			return readfile( $this->path ) !== false; // faster
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		}
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		return true;
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	}
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	/**
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	 * Send out a standard 404 message for a file
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	 *
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	 * @param string $fname Full name and path of the file to stream
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	 * @param integer $flags Bitfield of STREAM_* constants
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	 * @since 1.24
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	 */
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	public static function send404Message( $fname, $flags = 0 ) {
0 ignored issues
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Coding Style introduced by
send404Message uses the super-global variable $_SERVER which is generally not recommended.

Instead of super-globals, we recommend to explicitly inject the dependencies of your class. This makes your code less dependent on global state and it becomes generally more testable:

// Bad
class Router
{
    public function generate($path)
    {
        return $_SERVER['HOST'].$path;
    }
}

// Better
class Router
{
    private $host;

    public function __construct($host)
    {
        $this->host = $host;
    }

    public function generate($path)
    {
        return $this->host.$path;
    }
}

class Controller
{
    public function myAction(Request $request)
    {
        // Instead of
        $page = isset($_GET['page']) ? intval($_GET['page']) : 1;

        // Better (assuming you use the Symfony2 request)
        $page = $request->query->get('page', 1);
    }
}
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		if ( ( $flags & self::STREAM_HEADLESS ) == 0 ) {
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			HttpStatus::header( 404 );
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			header( 'Cache-Control: no-cache' );
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			header( 'Content-Type: text/html; charset=utf-8' );
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		}
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		$encFile = htmlspecialchars( $fname );
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		$encScript = htmlspecialchars( $_SERVER['SCRIPT_NAME'] );
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		echo "<!DOCTYPE html><html><body>
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			<h1>File not found</h1>
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			<p>Although this PHP script ($encScript) exists, the file requested for output
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			($encFile) does not.</p>
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			</body></html>
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			";
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	}
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	/**
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	 * Convert a Range header value to an absolute (start, end) range tuple
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	 *
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	 * @param string $range Range header value
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	 * @param integer $size File size
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	 * @return array|string Returns error string on failure (start, end, length)
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	 * @since 1.24
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	 */
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	public static function parseRange( $range, $size ) {
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		$m = [];
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		if ( preg_match( '#^bytes=(\d*)-(\d*)$#', $range, $m ) ) {
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			list( , $start, $end ) = $m;
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			if ( $start === '' && $end === '' ) {
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				$absRange = [ 0, $size - 1 ];
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			} elseif ( $start === '' ) {
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				$absRange = [ $size - $end, $size - 1 ];
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			} elseif ( $end === '' ) {
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				$absRange = [ $start, $size - 1 ];
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			} else {
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				$absRange = [ $start, $end ];
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			}
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			if ( $absRange[0] >= 0 && $absRange[1] >= $absRange[0] ) {
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				if ( $absRange[0] < $size ) {
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					$absRange[1] = min( $absRange[1], $size - 1 ); // stop at EOF
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					$absRange[2] = $absRange[1] - $absRange[0] + 1;
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					return $absRange;
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				} elseif ( $absRange[0] == 0 && $size == 0 ) {
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					return 'unrecognized'; // the whole file should just be sent
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				}
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			}
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			return 'invalid';
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		}
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		return 'unrecognized';
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	}
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	protected static function resetOutputBuffers() {
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		while ( ob_get_status() ) {
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			if ( !ob_end_clean() ) {
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				// Could not remove output buffer handler; abort now
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				// to avoid getting in some kind of infinite loop.
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				break;
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			}
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		}
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	}
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	/**
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	 * Determine the file type of a file based on the path
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	 *
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	 * @param string $filename Storage path or file system path
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	 * @return null|string
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	 */
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	protected static function contentTypeFromPath( $filename ) {
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		$ext = strrchr( $filename, '.' );
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		$ext = $ext === false ? '' : strtolower( substr( $ext, 1 ) );
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255 View Code Duplication
		switch ( $ext ) {
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			case 'gif':
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				return 'image/gif';
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			case 'png':
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				return 'image/png';
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			case 'jpg':
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				return 'image/jpeg';
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			case 'jpeg':
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				return 'image/jpeg';
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		}
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		return 'unknown/unknown';
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	}
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}
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