Implement rangeDownload() as driver and provide sendfile implementations for Nginx and Lighttpd

* The rangeDownload() function has been moved to libraries/Ddownload/drivers/Ddownload_php.php
* The nginx and lighttpd drivers can be set via $config['download_driver']

Signed-off-by: Pierre Schmitz <pierre@archlinux.de>

3 files changed, 168 insertions, 0 deletions

diff --git a/application/libraries/Ddownload/drivers/Ddownload_lighttpd.php b/application/libraries/Ddownload/drivers/Ddownload_lighttpd.php
new file mode 100644
index 000000000..31db4d340
--- /dev/null
+++ b/application/libraries/Ddownload/drivers/Ddownload_lighttpd.php
@@ -0,0 +1,27 @@
+<?php
+/*
+ * Copyright 2013 Pierre Schmitz <pierre@archlinux.de>
+ *
+ * Licensed under AGPLv3
+ * (see COPYING for full license text)
+ *
+ */
+
+class Ddownload_lighttpd extends Ddownload_Driver {
+
+	public function serveFile($file, $filename, $type)
+	{
+		$CI =& get_instance();
+		$upload_path = $CI->config->item('upload_path');
+
+		if (strpos($file, $upload_path) !== 0) {
+			show_error('Invalid file path');
+			return;
+		}
+
+		header('Content-disposition: inline; filename="'.$filename."\"\n");
+		header('Content-Type: '.$type."\n");
+		header('X-Sendfile: '.$file."\n");
+	}
+
+}
diff --git a/application/libraries/Ddownload/drivers/Ddownload_nginx.php b/application/libraries/Ddownload/drivers/Ddownload_nginx.php
new file mode 100644
index 000000000..5fb6ffa87
--- /dev/null
+++ b/application/libraries/Ddownload/drivers/Ddownload_nginx.php
@@ -0,0 +1,30 @@
+<?php
+/*
+ * Copyright 2013 Pierre Schmitz <pierre@archlinux.de>
+ *
+ * Licensed under AGPLv3
+ * (see COPYING for full license text)
+ *
+ */
+
+class Ddownload_nginx extends Ddownload_Driver {
+
+	public function serveFile($file, $filename, $type)
+	{
+		$CI =& get_instance();
+		$upload_path = $CI->config->item('upload_path');
+		$download_location = $CI->config->item('download_nginx_location');
+
+		if (strpos($file, $upload_path) === 0) {
+			$file_path = substr($file, strlen($upload_path));
+		} else {
+			show_error('Invalid file path');
+			return;
+		}
+
+		header('Content-disposition: inline; filename="'.$filename."\"\n");
+		header('Content-Type: '.$type."\n");
+		header('X-Accel-Redirect: '.$download_location.$file_path."\n");
+	}
+
+}
diff --git a/application/libraries/Ddownload/drivers/Ddownload_php.php b/application/libraries/Ddownload/drivers/Ddownload_php.php
new file mode 100644
index 000000000..344db53f0
--- /dev/null
+++ b/application/libraries/Ddownload/drivers/Ddownload_php.php
@@ -0,0 +1,111 @@
+<?php
+/*
+ * Copyright 2013 Florian "Bluewind" Pritz <bluewind@server-speed.net>
+ *
+ * Licensed under AGPLv3
+ * (see COPYING for full license text)
+ *
+ */
+
+class Ddownload_php extends Ddownload_Driver {
+
+	// Original source: http://www.phpfreaks.com/forums/index.php?topic=198274.msg895468#msg895468
+	public function serveFile($file, $filename, $type)
+	{
+		$fp = @fopen($file, 'r');
+
+		$size	= filesize($file); // File size
+		$length = $size;	   // Content length
+		$start	= 0;		   // Start byte
+		$end	= $size - 1;	   // End byte
+		// Now that we've gotten so far without errors we send the accept range header
+		/* At the moment we only support single ranges.
+		* Multiple ranges requires some more work to ensure it works correctly
+		* and comply with the spesifications: http://www.w3.org/Protocols/rfc2616/rfc2616-sec19.html#sec19.2
+		*
+		* Multirange support annouces itself with:
+		* header('Accept-Ranges: bytes');
+		*
+		* Multirange content must be sent with multipart/byteranges mediatype,
+		* (mediatype = mimetype)
+		* as well as a boundry header to indicate the various chunks of data.
+		*/
+		header("Accept-Ranges: 0-$length");
+		// header('Accept-Ranges: bytes');
+		// multipart/byteranges
+		// http://www.w3.org/Protocols/rfc2616/rfc2616-sec19.html#sec19.2
+		if (isset($_SERVER['HTTP_RANGE']))
+		{
+			$c_start = $start;
+			$c_end	 = $end;
+			// Extract the range string
+			list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
+			// Make sure the client hasn't sent us a multibyte range
+			if (strpos($range, ',') !== false)
+			{
+				// (?) Shoud this be issued here, or should the first
+				// range be used? Or should the header be ignored and
+				// we output the whole content?
+				header('HTTP/1.1 416 Requested Range Not Satisfiable');
+				header("Content-Range: bytes $start-$end/$size");
+				// (?) Echo some info to the client?
+				exit;
+			}
+			// If the range starts with an '-' we start from the beginning
+			// If not, we forward the file pointer
+			// And make sure to get the end byte if spesified
+			if ($range{0} == '-')
+			{
+				// The n-number of the last bytes is requested
+				$c_start = $size - substr($range, 1);
+			}
+			else
+			{
+				$range	= explode('-', $range);
+				$c_start = $range[0];
+				$c_end	 = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $size;
+			}
+			/* Check the range and make sure it's treated according to the specs.
+			* http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+			*/
+			// End bytes can not be larger than $end.
+			$c_end = ($c_end > $end) ? $end : $c_end;
+			// Validate the requested range and return an error if it's not correct.
+			if ($c_start > $c_end || $c_start > $size - 1 || $c_end >= $size)
+			{
+				header('HTTP/1.1 416 Requested Range Not Satisfiable');
+				header("Content-Range: bytes $start-$end/$size");
+				// (?) Echo some info to the client?
+				exit;
+			}
+			$start	= $c_start;
+			$end	= $c_end;
+			$length = $end - $start + 1; // Calculate new content length
+			fseek($fp, $start);
+			header('HTTP/1.1 206 Partial Content');
+			// Notify the client the byte range we'll be outputting
+			header("Content-Range: bytes $start-$end/$size");
+		}
+		header("Content-Length: $length");
+		header("Content-disposition: inline; filename=\"".$filename."\"\n");
+		header("Content-Type: ".$type."\n");
+
+		// Start buffered download
+		$buffer = 1024 * 8;
+		while(!feof($fp) && ($p = ftell($fp)) <= $end)
+		{
+			if ($p + $buffer > $end)
+			{
+				// In case we're only outputtin a chunk, make sure we don't
+				// read past the length
+				$buffer = $end - $p + 1;
+			}
+			set_time_limit(0); // Reset time limit for big files
+			echo fread($fp, $buffer);
+			flush(); // Free up memory. Otherwise large files will trigger PHP's memory limit.
+		}
+
+		fclose($fp);
+	}
+
+}