* Functions related to the output of file content
*/
class StreamFile {
- const READY_STREAM = 1;
- const NOT_MODIFIED = 2;
+ // Do not send any HTTP headers unless requested by caller (e.g. body only)
+ const STREAM_HEADLESS = 1;
+ // Do not try to tear down any PHP output buffers
+ const STREAM_ALLOW_OB = 2;
/**
* Stream a file to the browser, adding all the headings and fun stuff.
* and Content-Disposition.
*
* @param string $fname Full name and path of the file to stream
- * @param array $headers Any additional headers to send
+ * @param array $headers Any additional headers to send if the file exists
* @param bool $sendErrors Send error messages if errors occur (like 404)
+ * @param array $optHeaders HTTP request header map (e.g. "range") (use lowercase keys)
+ * @param integer $flags Bitfield of STREAM_* constants
* @throws MWException
* @return bool Success
*/
- public static function stream( $fname, $headers = array(), $sendErrors = true ) {
+ public static function stream(
+ $fname, $headers = [], $sendErrors = true, $optHeaders = [], $flags = 0
+ ) {
+ $section = new ProfileSection( __METHOD__ );
if ( FileBackend::isStoragePath( $fname ) ) { // sanity
throw new MWException( __FUNCTION__ . " given storage path '$fname'." );
}
- MediaWiki\suppressWarnings();
- $stat = stat( $fname );
- MediaWiki\restoreWarnings();
-
- $res = self::prepareForStream( $fname, $stat, $headers, $sendErrors );
- if ( $res == self::NOT_MODIFIED ) {
- $ok = true; // use client cache
- } elseif ( $res == self::READY_STREAM ) {
- $ok = readfile( $fname );
- } else {
- $ok = false; // failed
+ // Don't stream it out as text/html if there was a PHP error
+ if ( ( ( $flags & self::STREAM_HEADLESS ) == 0 || $headers ) && headers_sent() ) {
+ echo "Headers already sent, terminating.\n";
+ return false;
}
- return $ok;
- }
+ $headerFunc = ( $flags & self::STREAM_HEADLESS )
+ ? function ( $header ) {
+ // no-op
+ }
+ : function ( $header ) {
+ is_int( $header ) ? HttpStatus::header( $header ) : header( $header );
+ };
+
+ MediaWiki\suppressWarnings();
+ $info = stat( $fname );
+ MediaWiki\restoreWarnings();
- /**
- * Call this function used in preparation before streaming a file.
- * This function does the following:
- * (a) sends Last-Modified, Content-type, and Content-Disposition headers
- * (b) cancels any PHP output buffering and automatic gzipping of output
- * (c) sends Content-Length header based on HTTP_IF_MODIFIED_SINCE check
- *
- * @param string $path Storage path or file system path
- * @param array|bool $info File stat info with 'mtime' and 'size' fields
- * @param array $headers Additional headers to send
- * @param bool $sendErrors Send error messages if errors occur (like 404)
- * @return int|bool READY_STREAM, NOT_MODIFIED, or false on failure
- */
- public static function prepareForStream(
- $path, $info, $headers = array(), $sendErrors = true
- ) {
if ( !is_array( $info ) ) {
if ( $sendErrors ) {
- HttpStatus::header( 404 );
- header( 'Cache-Control: no-cache' );
- header( 'Content-Type: text/html; charset=utf-8' );
- $encFile = htmlspecialchars( $path );
- $encScript = htmlspecialchars( $_SERVER['SCRIPT_NAME'] );
- echo "<html><body>
- <h1>File not found</h1>
- <p>Although this PHP script ($encScript) exists, the file requested for output
- ($encFile) does not.</p>
- </body></html>
- ";
+ self::send404Message( $fname, $flags );
}
return false;
}
- // Sent Last-Modified HTTP header for client-side caching
- header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $info['mtime'] ) );
+ // Send Last-Modified HTTP header for client-side caching
+ $headerFunc( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $info['mtime'] ) );
- // Cancel output buffering and gzipping if set
- wfResetOutputBuffers();
+ if ( ( $flags & self::STREAM_ALLOW_OB ) == 0 ) {
+ // Cancel output buffering and gzipping if set
+ wfResetOutputBuffers();
+ }
- $type = self::contentTypeFromPath( $path );
+ $type = self::contentTypeFromPath( $fname );
if ( $type && $type != 'unknown/unknown' ) {
- header( "Content-type: $type" );
+ $headerFunc( "Content-type: $type" );
} else {
// Send a content type which is not known to Internet Explorer, to
// avoid triggering IE's content type detection. Sending a standard
// unknown content type here essentially gives IE license to apply
// whatever content type it likes.
- header( 'Content-type: application/x-wiki' );
+ $headerFunc( 'Content-type: application/x-wiki' );
}
- // Don't stream it out as text/html if there was a PHP error
- if ( headers_sent() ) {
- echo "Headers already sent, terminating.\n";
- return false;
+ // Don't send if client has up to date cache
+ if ( isset( $optHeaders['if-modified-since'] ) ) {
+ $modsince = preg_replace( '/;.*$/', '', $optHeaders['if-modified-since'] );
+ if ( wfTimestamp( TS_UNIX, $info['mtime'] ) <= strtotime( $modsince ) ) {
+ ini_set( 'zlib.output_compression', 0 );
+ $headerFunc( 304 );
+ return true; // ok
+ }
}
// Send additional headers
foreach ( $headers as $header ) {
- header( $header );
+ header( $header ); // always use header(); specifically requested
}
- // Don't send if client has up to date cache
- if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
- $modsince = preg_replace( '/;.*$/', '', $_SERVER['HTTP_IF_MODIFIED_SINCE'] );
- if ( wfTimestamp( TS_UNIX, $info['mtime'] ) <= strtotime( $modsince ) ) {
- ini_set( 'zlib.output_compression', 0 );
- HttpStatus::header( 304 );
- return self::NOT_MODIFIED; // ok
+ if ( isset( $optHeaders['range'] ) ) {
+ $range = self::parseRange( $optHeaders['range'], $info['size'] );
+ if ( is_array( $range ) ) {
+ $headerFunc( 206 );
+ $headerFunc( 'Content-Length: ' . $range[2] );
+ $headerFunc( "Content-Range: bytes {$range[0]}-{$range[1]}/{$info['size']}" );
+ } elseif ( $range === 'invalid' ) {
+ if ( $sendErrors ) {
+ $headerFunc( 416 );
+ $headerFunc( 'Cache-Control: no-cache' );
+ $headerFunc( 'Content-Type: text/html; charset=utf-8' );
+ $headerFunc( 'Content-Range: bytes */' . $info['size'] );
+ }
+ return false;
+ } else { // unsupported Range request (e.g. multiple ranges)
+ $range = null;
+ $headerFunc( 'Content-Length: ' . $info['size'] );
+ }
+ } else {
+ $range = null;
+ $headerFunc( 'Content-Length: ' . $info['size'] );
+ }
+
+ if ( is_array( $range ) ) {
+ $handle = fopen( $fname, 'rb' );
+ if ( $handle ) {
+ $ok = true;
+ fseek( $handle, $range[0] );
+ $remaining = $range[2];
+ while ( $remaining > 0 && $ok ) {
+ $bytes = min( $remaining, 8 * 1024 );
+ $data = fread( $handle, $bytes );
+ $remaining -= $bytes;
+ $ok = ( $data !== false );
+ print $data;
+ }
+ } else {
+ return false;
}
+ } else {
+ return readfile( $fname ) !== false; // faster
}
- header( 'Content-Length: ' . $info['size'] );
+ return true;
+ }
+
+ /**
+ * Send out a standard 404 message for a file
+ *
+ * @param string $fname Full name and path of the file to stream
+ * @param integer $flags Bitfield of STREAM_* constants
+ * @since 1.24
+ */
+ public static function send404Message( $fname, $flags = 0 ) {
+ if ( ( $flags & self::STREAM_HEADLESS ) == 0 ) {
+ HttpStatus::header( 404 );
+ header( 'Cache-Control: no-cache' );
+ header( 'Content-Type: text/html; charset=utf-8' );
+ }
+ $encFile = htmlspecialchars( $fname );
+ $encScript = htmlspecialchars( $_SERVER['SCRIPT_NAME'] );
+ echo "<!DOCTYPE html><html><body>
+ <h1>File not found</h1>
+ <p>Although this PHP script ($encScript) exists, the file requested for output
+ ($encFile) does not.</p>
+ </body></html>
+ ";
+ }
- return self::READY_STREAM; // ok
+ /**
+ * Convert a Range header value to an absolute (start, end) range tuple
+ *
+ * @param string $range Range header value
+ * @param integer $size File size
+ * @return array|string Returns error string on failure (start, end, length)
+ * @since 1.24
+ */
+ public static function parseRange( $range, $size ) {
+ $m = [];
+ if ( preg_match( '#^bytes=(\d*)-(\d*)$#', $range, $m ) ) {
+ list( , $start, $end ) = $m;
+ if ( $start === '' && $end === '' ) {
+ $absRange = [ 0, $size - 1 ];
+ } elseif ( $start === '' ) {
+ $absRange = [ $size - $end, $size - 1 ];
+ } elseif ( $end === '' ) {
+ $absRange = [ $start, $size - 1 ];
+ } else {
+ $absRange = [ $start, $end ];
+ }
+ if ( $absRange[0] >= 0 && $absRange[1] >= $absRange[0] ) {
+ if ( $absRange[0] < $size ) {
+ $absRange[1] = min( $absRange[1], $size - 1 ); // stop at EOF
+ $absRange[2] = $absRange[1] - $absRange[0] + 1;
+ return $absRange;
+ } elseif ( $absRange[0] == 0 && $size == 0 ) {
+ return 'unrecognized'; // the whole file should just be sent
+ }
+ }
+ return 'invalid';
+ }
+ return 'unrecognized';
}
/**
dépôts / lhc / web / wiklou.git / blobdiff