diff options
Diffstat (limited to 'phpBB/includes/functions_download.php')
| -rw-r--r-- | phpBB/includes/functions_download.php | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/phpBB/includes/functions_download.php b/phpBB/includes/functions_download.php index 87bf7a91a6..94d851e383 100644 --- a/phpBB/includes/functions_download.php +++ b/phpBB/includes/functions_download.php @@ -157,6 +157,16 @@ function send_file_to_browser($attachment, $upload_dir, $category) trigger_error('UNABLE_TO_DELIVER_FILE'); } + // Make sure the database record for the filesize is correct + if ($size > 0 && $size != $attachment['filesize']) + { + // Update database record + $sql = 'UPDATE ' . ATTACHMENTS_TABLE . ' + SET filesize = ' . (int) $size . ' + WHERE attach_id = ' . (int) $attachment['attach_id']; + $db->sql_query($sql); + } + // Now the tricky part... let's dance header('Pragma: public'); @@ -226,6 +236,16 @@ function send_file_to_browser($attachment, $upload_dir, $category) if ($fp !== false) { + // Deliver file partially if requested + if ($range = phpbb_http_byte_range($size)) + { + fseek($fp, $range['byte_pos_start']); + + send_status_line(206, 'Partial Content'); + header('Content-Range: bytes ' . $range['byte_pos_start'] . '-' . $range['byte_pos_end'] . '/' . $range['bytes_total']); + header('Content-Length: ' . $range['bytes_requested']); + } + while (!feof($fp)) { echo fread($fp, 8192); @@ -407,3 +427,151 @@ function file_gc() $db->sql_close(); exit; } + +/** +* HTTP range support (RFC 2616 Section 14.35) +* +* Allows browsers to request partial file content +* in case a download has been interrupted. +* +* @param int $filesize the size of the file in bytes we are about to deliver +* +* @return mixed false if the whole file has to be delivered +* associative array on success +*/ +function phpbb_http_byte_range($filesize) +{ + // Only call find_range_request() once. + static $request_array; + + if (!$filesize) + { + return false; + } + + if (!isset($request_array)) + { + $request_array = phpbb_find_range_request(); + } + + return (empty($request_array)) ? false : phpbb_parse_range_request($request_array, $filesize); +} + +/** +* Searches for HTTP range request in super globals. +* +* @return mixed false if no request found +* array of strings containing the requested ranges otherwise +* e.g. array(0 => '0-0', 1 => '123-125') +*/ +function phpbb_find_range_request() +{ + $globals = array( + array('_SERVER', 'HTTP_RANGE'), + array('_ENV', 'HTTP_RANGE'), + ); + + foreach ($globals as $array) + { + $global = $array[0]; + $key = $array[1]; + + // Make sure range request starts with "bytes=" + if (isset($GLOBALS[$global][$key]) && strpos($GLOBALS[$global][$key], 'bytes=') === 0) + { + // Strip leading 'bytes=' + // Multiple ranges can be separated by a comma + return explode(',', substr($GLOBALS[$global][$key], 6)); + } + } + + return false; +} + +/** +* Analyses a range request array. +* +* A range request can contain multiple ranges, +* we however only handle the first request and +* only support requests from a given byte to the end of the file. +* +* @param array $request_array array of strings containing the requested ranges +* @param int $filesize the full size of the file in bytes that has been requested +* +* @return mixed false if the whole file has to be delivered +* associative array on success +* byte_pos_start the first byte position, can be passed to fseek() +* byte_pos_end the last byte position +* bytes_requested the number of bytes requested +* bytes_total the full size of the file +*/ +function phpbb_parse_range_request($request_array, $filesize) +{ + // Go through all ranges + foreach ($request_array as $range_string) + { + $range = explode('-', trim($range_string)); + + // "-" is invalid, "0-0" however is valid and means the very first byte. + if (sizeof($range) != 2 || $range[0] === '' && $range[1] === '') + { + continue; + } + + if ($range[0] === '') + { + // Return last $range[1] bytes. + + if (!$range[1]) + { + continue; + } + + if ($range[1] >= $filesize) + { + return false; + } + + $first_byte_pos = $filesize - (int) $range[1]; + $last_byte_pos = $filesize - 1; + } + else + { + // Return bytes from $range[0] to $range[1] + + $first_byte_pos = (int) $range[0]; + $last_byte_pos = (int) $range[1]; + + if ($last_byte_pos && $last_byte_pos < $first_byte_pos) + { + // The requested range contains 0 bytes. + continue; + } + + if ($first_byte_pos >= $filesize) + { + // Requested range not satisfiable + return false; + } + + // Adjust last-byte-pos if it is absent or greater than the content. + if ($range[1] === '' || $last_byte_pos >= $filesize) + { + $last_byte_pos = $filesize - 1; + } + } + + // We currently do not support range requests that end before the end of the file + if ($last_byte_pos != $filesize - 1) + { + continue; + } + + return array( + 'byte_pos_start' => $first_byte_pos, + 'byte_pos_end' => $last_byte_pos, + 'bytes_requested' => $last_byte_pos - $first_byte_pos + 1, + 'bytes_total' => $filesize, + ); + } +} |