<?php
/**
* @brief HTTP Ranges Request/Response Class
* @author <a href='https://www.invisioncommunity.com'>Invision Power Services, Inc.</a>
* @copyright (c) Invision Power Services, Inc.
* @license https://www.invisioncommunity.com/legal/standards/
* @package Invision Community
* @since 19 May 2014
* @note This class facilitates parsing of HTTP Range requests and sending the appropriate response
*/
namespace IPS\Http;
/* To prevent PHP errors (extending class does not exist) revealing path */
if ( !\defined( '\IPS\SUITE_UNIQUE_KEY' ) )
{
header( ( isset( $_SERVER['SERVER_PROTOCOL'] ) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0' ) . ' 403 Forbidden' );
exit;
}
/**
* HTTP Ranges Request/Response Class
*/
class _Ranges extends Response
{
/**
* @brief File object
*/
public $file = NULL;
/**
* @brief Is this a range request?
*/
public $ranged = FALSE;
/**
* Constructor
*
* @param \IPS\File $file File object we are sending
* @param int $throttle Throttle speed (kb/sec)
* @return void
*/
public function __construct( $file, $throttle=0 )
{
/* Send some headers */
\IPS\Output::i()->sendHeader( 'Accept-Ranges: bytes' );
\IPS\Output::i()->sendHeader( "Content-Transfer-Encoding: binary" );
/* We will need the file size */
$filesize = $file->filesize();
$length = $filesize;
$range = 0;
$start_range = 0;
\IPS\Log::debug( "Range response initiated", 'ranges' );
/* Was this a ranged request? */
if( isset( $_SERVER['HTTP_RANGE'] ) )
{
\IPS\Log::debug( "This is a range request: " . $_SERVER['HTTP_RANGE'], 'ranges' );
/* Get the range */
list( $a, $range ) = explode( "=", $_SERVER['HTTP_RANGE'] );
/* Check for multiple ranges */
$ranges = explode( ",", $range );
/* Did we only find one range? */
if( \count($ranges) == 1 )
{
\IPS\Log::debug( "Only one range detected", 'ranges' );
/* Get the actual range start and end */
list( $start_range, $end_range ) = explode( "-", $range );
/* If there is no start, we want the last x bytes */
if( \strlen( $start_range ) == 0 )
{
$size = $filesize - 1;
$length = $end_range + 1;
}
/* Or did we want the first x bytes? */
else if( \strlen( $end_range ) == 0 )
{
$size = $filesize - 1;
$length = $size - $start_range + 1;
}
/* Or a specific range with start and end specified */
else
{
$size = $end_range;
$length = $end_range - $start_range + 1;
}
/* If the range is invalid we need to send a 416 header and let the client know the valid range */
if( $start_range > $size OR $end_range > $size )
{
\IPS\Log::debug( "Invalid range, responding with 416 header. Requested {$start_range} - {$end_range} out of {$size}", 'ranges' );
\IPS\Output::i()->sendStatusCodeHeader( 416 );
\IPS\Output::i()->sendHeader( "Content-Range: */{$filesize}" );
return;
}
/* Otherwise send the 206 header */
else
{
/* If the end range is larger than the filesize, correct the end range to the filesize */
if ( $end_range > $filesize )
{
$size = $filesize - 1;
}
\IPS\Log::debug( "Sending requested range with 206 header: {$start_range} - {$size} out of {$filesize}", 'ranges' );
\IPS\Output::i()->sendStatusCodeHeader( 206 );
\IPS\Output::i()->sendHeader( "Content-Range: bytes {$start_range}-{$size}/{$filesize}" );
}
/* A couple more headers for good measure */
if( !ini_get('zlib.output_compression') OR ini_get('zlib.output_compression') == 'off' )
{
\IPS\Output::i()->sendHeader( "Content-Length: " . $filesize );
}
}
/* Or did they get froggy and request multiple ranges? */
else
{
/* Start parsing the ranges */
$the_responses = array();
foreach( $ranges as $arange )
{
\IPS\Log::debug( "Multiple ranges: {$start_range} - {$end_range}", 'ranges' );
/* Get the actual range start and end */
list( $start_range, $end_range ) = explode( "-", $arange );
/* If there is no start, we want the last x bytes */
if( \strlen( $start_range ) == 0 )
{
$size = $filesize - 1;
$length = $end_range + 1;
}
/* Or did we want the first x bytes? */
else if( \strlen( $end_range ) == 0 )
{
$size = $filesize - 1;
$length = $size - $start_range + 1;
}
/* Or a specific range with start and end specified */
else
{
$size = $end_range;
$length = $end_range - $start_range + 1;
}
/* If the range is invalid we need to send a 416 header and let the client know the valid range */
if( $start_range > $size OR $end_range > $size )
{
\IPS\Log::debug( "This range out of multiple ranges was invalid", 'ranges' );
\IPS\Output::i()->sendStatusCodeHeader( 416 );
\IPS\Output::i()->sendHeader( "Content-Range: */{$filesize}" );
return;
}
/* Otherwise store this range */
else
{
$the_responses[] = array( $start_range, $size, $length );
}
}
/* Did we still only have one range? */
if( \count($the_responses) == 1 )
{
$length = $the_responses[0][2];
$start_range = $the_responses[0][0];
$size = $the_responses[0][1];
$the_responses = array();
\IPS\Log::debug( "One range out of multiple ranges to respond: {$start_range} - {$size} out of {$filesize}", 'ranges' );
\IPS\Output::i()->sendStatusCodeHeader( 206 );
\IPS\Output::i()->sendHeader( "Content-Range: bytes {$start_range}-{$size}/{$filesize}" );
/* A couple more headers for good measure */
if( !ini_get('zlib.output_compression') OR ini_get('zlib.output_compression') == 'off' )
{
\IPS\Output::i()->sendHeader( "Content-Length: " . $filesize );
}
}
/* Now we're working with something exciting */
else if( \count($the_responses) > 1 )
{
$content_length = 0;
\IPS\Log::debug( "Multiple range responses, using boundary", 'ranges' );
foreach( $the_responses as $part )
{
$content_length += \strlen( "\r\n--IPDOWNLOADSBOUNDARYMARKER\r\n" );
$content_length += \strlen( "Content-Type: " . \IPS\File::getMimeType( $file->originalFilename ) . "\r\n" );
$content_length += \strlen( "Content-Range: bytes {$part[0]}-{$part[1]}/{$filesize}\r\n\r\n" );
$content_length += $part[2];
}
$content_length += \strlen( "\r\n--IPDOWNLOADSBOUNDARYMARKER--\r\n" );
\IPS\Output::i()->sendStatusCodeHeader( 206 );
\IPS\Output::i()->sendHeader( "Content-Type: multipart/x-byteranges; boundary=IPDOWNLOADSBOUNDARYMARKER" );
if( !ini_get('zlib.output_compression') OR ini_get('zlib.output_compression') == 'off' )
{
\IPS\Output::i()->sendHeader( "Content-Length: " . $content_length );
}
}
}
}
/* No range */
else
{
\IPS\Log::debug( "No range requested, sending entire file", 'ranges' );
$size = $filesize - 1;
\IPS\Output::i()->sendStatusCodeHeader( 200 );
if( !ini_get('zlib.output_compression') OR ini_get('zlib.output_compression') == 'off' )
{
\IPS\Output::i()->sendHeader( "Content-Length: " . $filesize );
}
\IPS\Output::i()->sendHeader( "Content-Range: bytes 0-{$size}/{$filesize}" );
}
/* Not sending multiple ranges */
if( !isset( $the_responses ) OR !\count( $the_responses ) )
{
\IPS\Output::i()->sendHeader( 'Content-Type: ' . \IPS\File::getMimeType( $file->originalFilename ) );
\IPS\Output::i()->sendHeader( 'Content-Disposition: ' . \IPS\Output::getContentDisposition( 'attachment', $file->originalFilename ) );
}
/* Turn off output buffering if it is on */
while( ob_get_level() > 0 )
{
ob_end_clean();
}
/* Throttling? */
$throttle = ( $throttle > 0 ) ? ( $throttle * 1024 ) : NULL;
/* Do we have multiple ranges? */
if( isset( $the_responses ) AND \count($the_responses) )
{
/* Loop over each range */
foreach( $the_responses as $part )
{
$length = $part[2];
echo "\r\n--IPDOWNLOADSBOUNDARYMARKER\r\n";
echo "Content-Type: " . \IPS\File::getMimeType( $file->originalFilename ) . "\r\n";
echo "Content-Range: bytes {$part[0]}-{$part[1]}/{$filesize}\r\n\r\n";
$file->printFile( $part[0], $part[2], $throttle );
}
echo "\r\n--IPDOWNLOADSBOUNDARYMARKER--\r\n";
}
/* Just a single range? */
else
{
$file->printFile( $start_range, $length, $throttle );
}
}
/**
* Determine if this is a range request for the start of the file
*
* @return bool
*/
public static function isStartOfFile()
{
/* Was this a ranged request? */
if( isset( $_SERVER['HTTP_RANGE'] ) )
{
/* Get the range */
list( $a, $range ) = explode( "=", $_SERVER['HTTP_RANGE'] );
/* Check for multiple ranges */
$ranges = explode( ",", $range );
/* Did we only find one range? */
if( \count($ranges) == 1 )
{
/* Get the actual range start and end */
list( $start_range, $end_range ) = explode( "-", $range );
if( \strlen( $start_range ) == 0 )
{
return TRUE;
}
else if( \strlen( $end_range ) == 0 )
{
return FALSE;
}
else
{
return ( $start_range == 0 ) ? TRUE : FALSE;
}
}
/* Or did they get froggy and request multiple ranges? */
else
{
foreach( $ranges as $arange )
{
/* Get the actual range start and end */
list( $start_range, $end_range ) = explode( "-", $arange );
if( \strlen( $start_range ) == 0 )
{
return TRUE;
}
else if( \strlen( $end_range ) == 0 )
{
continue;
}
else
{
if( $start_range == 0 )
{
return TRUE;
}
}
}
return FALSE;
}
}
/* No range */
else
{
return TRUE;
}
}
}