The Zip class has undergone a substantial re-write for speed and clarity

2 files changed, 102 insertions, 120 deletions

diff --git a/system/libraries/Zip.php b/system/libraries/Zip.php
index 97695a07f..ed476ab48 100644
--- a/system/libraries/Zip.php
+++ b/system/libraries/Zip.php
@@ -32,9 +32,10 @@
  */

 class CI_Zip  {

 

-	var $zipfile	= '';	

-	var $zipdata	= array();

-	var $directory	= array();

+	var $zipdata 	= '';

+	var $directory 	= '';

+    var $entries 	= 0;

+    var $file_num 	= 0;

 	var $offset		= 0;

 

 	function CI_Zip()

@@ -61,7 +62,7 @@ class CI_Zip  {
 			{

 				$dir .= '/';

 			}

-		

+

 			$this->_add_dir($dir);

 		}

 	}

@@ -78,35 +79,36 @@ class CI_Zip  {
 	function _add_dir($dir)

 	{

 		$dir = str_replace("\\", "/", $dir);

-		

-		$this->zipdata[] = "\x50\x4b\x03\x04\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"

-							.pack('V', 0)

-							.pack('V', 0)

-							.pack('V', 0)

-							.pack('v', strlen($dir))

-							.pack('v', 0)

-							.$dir

-							.pack('V', 0)

-							.pack('V', 0)

-							.pack('V', 0);

-		

-		$newoffset = strlen(implode('', $this->zipdata));

-		

-		$record = "\x50\x4b\x01\x02\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"

-					.pack('V',0)

-					.pack('V',0)

-					.pack('V',0)

-					.pack('v', strlen($dir))

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('V', 16)

-					.pack('V', $this->offset)

-					.$dir;

-		

-		$this->offset = $newoffset;

-		$this->directory[] = $record;

+

+		$this->zipdata .=

+			"\x50\x4b\x03\x04\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"

+			.pack('V', 0) // crc32

+			.pack('V', 0) // compressed filesize

+			.pack('V', 0) // uncompressed filesize

+			.pack('v', strlen($dir)) // length of pathname

+			.pack('v', 0) // extra field length

+			.$dir

+			// below is "data descriptor" segment

+			.pack('V', 0) // crc32

+			.pack('V', 0) // compressed filesize

+			.pack('V', 0); // uncompressed filesize

+

+		$this->directory .=

+			"\x50\x4b\x01\x02\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"

+			.pack('V',0) // crc32

+			.pack('V',0) // compressed filesize

+			.pack('V',0) // uncompressed filesize

+			.pack('v', strlen($dir)) // length of pathname

+			.pack('v', 0) // extra field length

+			.pack('v', 0) // file comment length

+			.pack('v', 0) // disk number start

+			.pack('v', 0) // internal file attributes

+			.pack('V', 16) // external file attributes - 'directory' bit set

+			.pack('V', $this->offset) // relative offset of local header

+			.$dir;

+

+		$this->offset = strlen($this->zipdata);

+		$this->entries++;

 	}

 	

 	// --------------------------------------------------------------------

@@ -137,7 +139,7 @@ class CI_Zip  {
 			$this->_add_data($filepath, $data);

 		}

 	}

-	

+

 	// --------------------------------------------------------------------

 

 	/**

@@ -149,41 +151,43 @@ class CI_Zip  {
 	 * @return	void

 	 */	

 	function _add_data($filepath, $data)

-	{	

+	{

 		$filepath = str_replace("\\", "/", $filepath);

-			

-		$oldlen	= strlen($data);

-		$crc32	= crc32($data);

-		

+

+		$uncompressed_size = strlen($data);

+		$crc32  = crc32($data);

+

 		$gzdata = gzcompress($data);

 		$gzdata = substr($gzdata, 2, -4);

-		$newlen = strlen($gzdata);

-	

-		$this->zipdata[] = "\x50\x4b\x03\x04\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"

-							.pack('V', $crc32)

-							.pack('V', $newlen)

-							.pack('V', $oldlen)

-							.pack('v', strlen($filepath))

-							.pack('v', 0)

-							.$filepath

-							.$gzdata;

-			

-		$newoffset = strlen(implode("", $this->zipdata));

-		

-		$record = "\x50\x4b\x01\x02\x00\x00\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"

-					.pack('V', $crc32)

-					.pack('V', $newlen)

-					.pack('V', $oldlen)

-					.pack('v', strlen($filepath))

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('v', 0)

-					.pack('V', 32)

-					.pack('V', $this->offset);

-		

-		$this->offset = $newoffset;

-		$this->directory[] = $record.$filepath;

+		$compressed_size = strlen($gzdata);

+

+		$this->zipdata .=

+			"\x50\x4b\x03\x04\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"

+			.pack('V', $crc32)

+			.pack('V', $compressed_size)

+			.pack('V', $uncompressed_size)

+			.pack('v', strlen($filepath)) // length of filename

+			.pack('v', 0) // extra field length

+			.$filepath

+			.$gzdata; // "file data" segment

+

+		$this->directory .=

+			"\x50\x4b\x01\x02\x00\x00\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"

+			.pack('V', $crc32)

+			.pack('V', $compressed_size)

+			.pack('V', $uncompressed_size)

+			.pack('v', strlen($filepath)) // length of filename

+			.pack('v', 0) // extra field length

+			.pack('v', 0) // file comment length

+			.pack('v', 0) // disk number start

+			.pack('v', 0) // internal file attributes

+			.pack('V', 32) // external file attributes - 'archive' bit set

+			.pack('V', $this->offset) // relative offset of local header

+			.$filepath;

+

+		$this->offset = strlen($this->zipdata);

+		$this->entries++;

+		$this->file_num++;

 	}

 	

 	// --------------------------------------------------------------------

@@ -200,7 +204,7 @@ class CI_Zip  {
 		{

 			return FALSE;

 		}

-	

+

 		if (FALSE !== ($data = file_get_contents($path)))

 		{

 			$name = str_replace("\\", "/", $path);

@@ -209,7 +213,7 @@ class CI_Zip  {
 			{

 				$name = preg_replace("|.*/(.+)|", "\\1", $name);

 			}

-			

+

 			$this->add_data($name, $data);

 			return TRUE;

 		}

@@ -261,30 +265,21 @@ class CI_Zip  {
 	 */	

 	function get_zip()

 	{

-		// We cache the zip data so multiple calls

-		// do not require recompiling

-		if ($this->zipfile != '')

-		{

-			return $this->zipfile;

-		}

-	

 		// Is there any data to return?

-		if (count($this->zipdata) == 0)

+		if ($this->entries == 0)

 		{

 			return FALSE;

 		}

-	

-		$data	= implode('', $this->zipdata);

-		$dir	= implode('', $this->directory);

-				

-		$this->zipfile = $data.$dir."\x50\x4b\x05\x06\x00\x00\x00\x00"

-						.pack('v', sizeof($this->directory))

-						.pack('v', sizeof($this->directory))

-						.pack('V', strlen($dir))

-						.pack('V', strlen($data))

-						."\x00\x00";

-		

-		return $this->zipfile;

+

+		$zip_data = $this->zipdata;

+		$zip_data .= $this->directory."\x50\x4b\x05\x06\x00\x00\x00\x00";

+		$zip_data .= pack('v', $this->entries); // total # of entries "on this disk"

+		$zip_data .= pack('v', $this->entries); // total # of entries overall

+		$zip_data .= pack('V', strlen($this->directory)); // size of central dir

+		$zip_data .= pack('V', strlen($this->zipdata)); // offset to start of central dir

+		$zip_data .= "\x00\x00"; // .zip file comment length

+

+		return $zip_data;

 	}

 	

 	// --------------------------------------------------------------------

@@ -305,7 +300,7 @@ class CI_Zip  {
 		{

 			return FALSE;

 		}

-		

+

 		flock($fp, LOCK_EX);	

 		fwrite($fp, $this->get_zip());

 		flock($fp, LOCK_UN);

@@ -323,35 +318,20 @@ class CI_Zip  {
 	 * @param	string	the file name

 	 * @param	string	the data to be encoded

 	 * @return	bool

-	 */		

+	 */

 	function download($filename = 'backup.zip')

 	{

-		if ( ! preg_match("|.+?\.zip$|", $filename))

-		{

-			$filename .= '.zip';

-		}

-	

-		if (strstr($_SERVER['HTTP_USER_AGENT'], "MSIE"))

-		{

-			header('Content-Type: application/x-zip');

-			header('Content-Disposition: inline; filename="'.$filename.'"');

-			header('Expires: 0');

-			header('Cache-Control: must-revalidate, post-check=0, pre-check=0');

-			header("Content-Transfer-Encoding: binary");

-			header('Pragma: public');

-			header("Content-Length: ".strlen($this->get_zip()));

-		}

-		else

-		{

-			header('Content-Type: application/x-zip');

-			header('Content-Disposition: attachment; filename="'.$filename.'"');

-			header("Content-Transfer-Encoding: binary");

-			header('Expires: 0');

-			header('Pragma: no-cache');

-			header("Content-Length: ".strlen($this->get_zip()));

-		}

-	

-		exit($this->get_zip());

+        if ( ! preg_match("|.+?\.zip$|", $filename))

+        {

+            $filename .= '.zip';

+        }

+

+        $zip_content =& $this->get_zip();

+

+        $CI =& get_instance();

+        $CI->load->helper('download');

+		

+		force_download($filename, $zip_content);

 	}

 

 	// --------------------------------------------------------------------

@@ -367,10 +347,11 @@ class CI_Zip  {
 	 */		

 	function clear_data()

 	{

-		$this->zipfile		= '';

-		$this->zipdata 		= array();

-		$this->directory	= array();

-		$this->offset		= array();

+		$this->zipdata   = '';

+		$this->directory = '';

+		$this->entries   = 0;

+		$this->file_num  = 0;

+		$this->offset    = 0;

 	}

 	

 }

diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index 3d0772147..ffa400ca8 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -97,6 +97,7 @@ SVN Revision: 1145</p>
 			<li><a href="libraries/unit_testing.html">Unit Testing</a> results are now colour coded, and a change was made to the default template of results.</li>

 			<li>Added a valid_emails rule to the <a href="libraries/validation.html">Validation</a> class.</li>

 			<li>The <a href="libraries/zip.html">Zip class</a> now exits within <kbd>download()</kbd>.</li>

+			<li>The <a href="libraries/zip.html">Zip class</a> has undergone a substantial re-write for speed and clarity (thanks stanleyxu for the hard work and code contribution!)</li>

 		</ul>

 	</li>

     <li>Helpers