Merge branch 'develop' into feature/user-guide-cleanup

1 files changed, 156 insertions, 132 deletions

diff --git a/system/core/Output.php b/system/core/Output.php
index 06d7a866b..2ad8e90fa 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -58,21 +58,21 @@ class CI_Output {
 	 *
 	 * @var	array
 	 */
-	public $headers =	array();
+	public $headers = array();
 
 	/**
 	 * List of mime types
 	 *
 	 * @var	array
 	 */
-	public $mimes =		array();
+	public $mimes =	array();
 
 	/**
 	 * Mime-type for the current page
 	 *
 	 * @var	string
 	 */
-	protected $mime_type	= 'text/html';
+	protected $mime_type = 'text/html';
 
 	/**
 	 * Enable Profiler flag
@@ -82,11 +82,18 @@ class CI_Output {
 	public $enable_profiler = FALSE;
 
 	/**
-	 * zLib output compression flag
+	 * php.ini zlib.output_compression flag
 	 *
 	 * @var	bool
 	 */
-	protected $_zlib_oc =		FALSE;
+	protected $_zlib_oc = FALSE;
+
+	/**
+	 * CI output compression flag
+	 *
+	 * @var	bool
+	 */
+	protected $_compress_output = FALSE;
 
 	/**
 	 * List of profiler sections
@@ -102,7 +109,7 @@ class CI_Output {
 	 *
 	 * @var	bool
 	 */
-	public $parse_exec_vars =	TRUE;
+	public $parse_exec_vars = TRUE;
 
 	/**
 	 * Class constructor
@@ -114,6 +121,11 @@ class CI_Output {
 	public function __construct()
 	{
 		$this->_zlib_oc = (bool) @ini_get('zlib.output_compression');
+		$this->_compress_output = (
+			$this->_zlib_oc === FALSE
+			&& config_item('compress_output') === TRUE
+			&& extension_loaded('zlib')
+		);
 
 		// Get mime types for later
 		$this->mimes =& get_mimes();
@@ -436,15 +448,14 @@ class CI_Output {
 		if ($this->parse_exec_vars === TRUE)
 		{
 			$memory	= round(memory_get_usage() / 1024 / 1024, 2).'MB';
-
 			$output = str_replace(array('{elapsed_time}', '{memory_usage}'), array($elapsed, $memory), $output);
 		}
 
 		// --------------------------------------------------------------------
 
 		// Is compression requested?
-		if ($CFG->item('compress_output') === TRUE && $this->_zlib_oc === FALSE
-			&& extension_loaded('zlib')
+		if (isset($CI) // This means that we're not serving a cache file, if we were, it would already be compressed
+			&& $this->_compress_output === TRUE
 			&& isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE)
 		{
 			ob_start('ob_gzhandler');
@@ -468,6 +479,21 @@ class CI_Output {
 		// simply echo out the data and exit.
 		if ( ! isset($CI))
 		{
+			if ($this->_compress_output === TRUE)
+			{
+				if (isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE)
+				{
+					header('Content-Encoding: gzip');
+					header('Content-Length: '.strlen($output));
+				}
+				else
+				{
+					// User agent doesn't support gzip compression,
+					// so we'll have to decompress our cache
+					$output = gzinflate(substr($output, 10, -8));
+				}
+			}
+
 			echo $output;
 			log_message('debug', 'Final output sent to browser');
 			log_message('debug', 'Total execution time: '.$elapsed);
@@ -530,9 +556,9 @@ class CI_Output {
 			return;
 		}
 
-		$uri =	$CI->config->item('base_url').
-				$CI->config->item('index_page').
-				$CI->uri->uri_string();
+		$uri = $CI->config->item('base_url')
+			.$CI->config->item('index_page')
+			.$CI->uri->uri_string();
 
 		$cache_path .= md5($uri);
 
@@ -542,17 +568,39 @@ class CI_Output {
 			return;
 		}
 
-		$expire = time() + ($this->cache_expiration * 60);
-
-		// Put together our serialized info.
-		$cache_info = serialize(array(
-			'expire'	=> $expire,
-			'headers'	=> $this->headers
-		));
-
 		if (flock($fp, LOCK_EX))
 		{
-			fwrite($fp, $cache_info.'ENDCI--->'.$output);
+			// If output compression is enabled, compress the cache
+			// itself, so that we don't have to do that each time
+			// we're serving it
+			if ($this->_compress_output === TRUE)
+			{
+				$output = gzencode($output);
+
+				if ($this->get_header('content-type') === NULL)
+				{
+					$this->set_content_type($this->mime_type);
+				}
+			}
+
+			$expire = time() + ($this->cache_expiration * 60);
+
+			// Put together our serialized info.
+			$cache_info = serialize(array(
+				'expire'	=> $expire,
+				'headers'	=> $this->headers
+			));
+
+			$output = $cache_info.'ENDCI--->'.$output;
+
+			for ($written = 0, $length = strlen($output); $written < $length; $written += $result)
+			{
+				if (($result = fwrite($fp, substr($output, $written))) === FALSE)
+				{
+					break;
+				}
+			}
+
 			flock($fp, LOCK_UN);
 		}
 		else
@@ -560,13 +608,22 @@ class CI_Output {
 			log_message('error', 'Unable to secure a file lock for file at: '.$cache_path);
 			return;
 		}
+
 		fclose($fp);
-		@chmod($cache_path, FILE_WRITE_MODE);
 
-		log_message('debug', 'Cache file written: '.$cache_path);
+		if (is_int($result))
+		{
+			@chmod($cache_path, FILE_WRITE_MODE);
+			log_message('debug', 'Cache file written: '.$cache_path);
 
-		// Send HTTP cache-control headers to browser to match file cache settings.
-		$this->set_cache_header($_SERVER['REQUEST_TIME'], $expire);
+			// Send HTTP cache-control headers to browser to match file cache settings.
+			$this->set_cache_header($_SERVER['REQUEST_TIME'], $expire);
+		}
+		else
+		{
+			@unlink($cache_path);
+			log_message('error', 'Unable to write the complete cache content at: '.$cache_path);
+		}
 	}
 
 	// --------------------------------------------------------------------
@@ -701,7 +758,7 @@ class CI_Output {
 		else
 		{
 			header('Pragma: public');
-			header('Cache-Control: max-age=' . $max_age . ', public');
+			header('Cache-Control: max-age='.$max_age.', public');
 			header('Expires: '.gmdate('D, d M Y H:i:s', $expiration).' GMT');
 			header('Last-modified: '.gmdate('D, d M Y H:i:s', $last_modified).' GMT');
 		}
@@ -740,13 +797,13 @@ class CI_Output {
 				preg_match_all('{<style.+</style>}msU', $output, $style_clean);
 				foreach ($style_clean[0] as $s)
 				{
-					$output = str_replace($s, $this->_minify_script_style($s, TRUE), $output);
+					$output = str_replace($s, $this->_minify_js_css($s, 'css', TRUE), $output);
 				}
 
 				// Minify the javascript in <script> tags.
 				foreach ($javascript_clean[0] as $s)
 				{
-					$javascript_mini[] = $this->_minify_script_style($s, TRUE);
+					$javascript_mini[] = $this->_minify_js_css($s, 'js', TRUE);
 				}
 
 				// Replace multiple spaces with a single space.
@@ -792,13 +849,14 @@ class CI_Output {
 			break;
 
 			case 'text/css':
+
+				return $this->_minify_js_css($output, 'css');
+
 			case 'text/javascript':
 			case 'application/javascript':
 			case 'application/x-javascript':
 
-				$output = $this->_minify_script_style($output);
-
-			break;
+				return $this->_minify_js_css($output, 'js');
 
 			default: break;
 		}
@@ -809,134 +867,100 @@ class CI_Output {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Minify Style and Script
-	 *
-	 * Reduce excessive size of CSS/JavaScript content.  To remove spaces this
-	 * script walks the string as an array and determines if the pointer is inside
-	 * a string created by single quotes or double quotes.  spaces inside those
-	 * strings are not stripped.  Opening and closing tags are severed from
-	 * the string initially and saved without stripping whitespace to preserve
-	 * the tags and any associated properties if tags are present
+	 * Minify JavaScript and CSS code
 	 *
-	 * Minification logic/workflow is similar to methods used by Douglas Crockford
-	 * in JSMIN. http://www.crockford.com/javascript/jsmin.html
+	 * Strips comments and excessive whitespace characters
 	 *
-	 * KNOWN ISSUE: ending a line with a closing parenthesis ')' and no semicolon
-	 * where there should be one will break the Javascript. New lines after a
-	 * closing parenthesis are not recognized by the script. For best results
-	 * be sure to terminate lines with a semicolon when appropriate.
-	 *
-	 * @param	string	$output		Output to minify
-	 * @param	bool	$has_tags	Specify if the output has style or script tags
-	 * @return	string	Minified output
+	 * @param	string	$output
+	 * @param	string	$type	'js' or 'css'
+	 * @param	bool	$tags	Whether $output contains the 'script' or 'style' tag
+	 * @return	string
 	 */
-	protected function _minify_script_style($output, $has_tags = FALSE)
+	protected function _minify_js_css($output, $type, $tags = FALSE)
 	{
-		// We only need this if there are tags in the file
-		if ($has_tags === TRUE)
+		if ($tags === TRUE)
 		{
-			// Remove opening tag and save for later
-			$pos = strpos($output, '>') + 1;
-			$open_tag = substr($output, 0, $pos);
-			$output = substr_replace($output, '', 0, $pos);
+			$tags = array('close' => strrchr($output, '<'));
 
-			// Remove closing tag and save it for later
-			$pos = strpos($output, '</');
-			$closing_tag = substr($output, $pos, strlen($output));
-			$output = substr_replace($output, '', $pos);
-		}
+			$open_length = strpos($output, '>') + 1;
+			$tags['open'] = substr($output, 0, $open_length);
 
-		// Remove CSS comments
-		$output = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!i', '', $output);
+			$output = substr($output, $open_length, -strlen($tags['close']));
 
-		// Remove spaces around curly brackets, colons,
-		// semi-colons, parenthesis, commas
-		$chunks = preg_split('/([\'|"]).+(?![^\\\]\\1)\\1/iU', $output, -1, PREG_SPLIT_OFFSET_CAPTURE);
-		for ($i = count($chunks) - 1; $i >= 0; $i--)
-		{
-			$output = substr_replace(
-				$output,
-				preg_replace('/\s*(:|;|,|}|{|\(|\))\s*/i', '$1', $chunks[$i][0]),
-				$chunks[$i][1],
-				strlen($chunks[$i][0])
-			);
+			// Strip spaces from the tags
+			$tags = preg_replace('#\s{2,}#', ' ', $tags);
 		}
 
-		// Replace tabs with spaces
-		// Replace carriage returns & multiple new lines with single new line
-		// and trim any leading or trailing whitespace
-		$output = trim(preg_replace(array('/\t+/', '/\r/', '/\n+/'), array(' ', "\n", "\n"), $output));
+		$output = trim($output);
 
-		// Remove spaces when safe to do so.
-		$in_string = $in_dstring = $prev = FALSE;
-		$array_output = str_split($output);
-		foreach ($array_output as $key => $value)
+		if ($type === 'js')
 		{
-			if ($in_string === FALSE && $in_dstring === FALSE)
+			// Catch all string literals and comment blocks
+			if (preg_match_all('#((?:((?<!\\\)\'|")|(/\*)|(//)).*(?(2)(?<!\\\)\2|(?(3)\*/|\n)))#msuUS', $output, $match, PREG_OFFSET_CAPTURE))
 			{
-				if ($value === ' ')
+				$js_literals = $js_code = array();
+				for ($match = $match[0], $c = count($match), $i = $pos = $offset = 0; $i < $c; $i++)
 				{
-					// Get the next element in the array for comparisons
-					$next = $array_output[$key + 1];
-
-					// Strip spaces preceded/followed by a non-ASCII character
-					// or not preceded/followed by an alphanumeric
-					// or not preceded/followed \ $ and _
-					if ((preg_match('/^[\x20-\x7f]*$/D', $next) OR preg_match('/^[\x20-\x7f]*$/D', $prev))
-						&& ( ! ctype_alnum($next) OR ! ctype_alnum($prev))
-						&& ! in_array($next, array('\\', '_', '$'), TRUE)
-						&& ! in_array($prev, array('\\', '_', '$'), TRUE)
-					)
+					$js_code[$pos++] = trim(substr($output, $offset, $match[$i][1] - $offset));
+					$offset = $match[$i][1] + strlen($match[$i][0]);
+
+					// Save only if we haven't matched a comment block
+					if ($match[$i][0][0] !== '/')
 					{
-						unset($array_output[$key]);
+						$js_literals[$pos++] = array_shift($match[$i]);
 					}
 				}
-				else
-				{
-					// Save this value as previous for the next iteration
-					// if it is not a blank space
-					$prev = $value;
-				}
-			}
+				$js_code[$pos] = substr($output, $offset);
 
-			if ($value === "'")
-			{
-				$in_string = ! $in_string;
+				// $match might be quite large, so free it up together with other vars that we no longer need
+				unset($match, $offset, $pos);
 			}
-			elseif ($value === '"')
+			else
 			{
-				$in_dstring = ! $in_dstring;
+				$js_code = array($output);
+				$js_literals = array();
 			}
+
+			$varname = 'js_code';
+		}
+		else
+		{
+			$varname = 'output';
 		}
 
-		// Put the string back together after spaces have been stripped
-		$output = implode($array_output);
+		// Standartize new lines
+		$$varname = str_replace(array("\r\n", "\r"), "\n", $$varname);
 
-		// Remove new line characters unless previous or next character is
-		// printable or Non-ASCII
-		preg_match_all('/[\n]/', $output, $lf, PREG_OFFSET_CAPTURE);
-		$removed_lf = 0;
-		foreach ($lf as $feed_position)
+		if ($type === 'js')
 		{
-			foreach ($feed_position as $position)
-			{
-				$position = $position[1] - $removed_lf;
-				$next = $output[$position + 1];
-				$prev = $output[$position - 1];
-				if ( ! ctype_print($next) && ! ctype_print($prev)
-					&& ! preg_match('/^[\x20-\x7f]*$/D', $next)
-					&& ! preg_match('/^[\x20-\x7f]*$/D', $prev)
-				)
-				{
-					$output = substr_replace($output, '', $position, 1);
-					$removed_lf++;
-				}
-			}
+			$patterns = array(
+				'#\s*([!\#%&()*+,\-./:;<=>?@\[\]^`{|}~])\s*#'	=> '$1',	// Remove spaces following and preceeding JS-wise non-special & non-word characters
+				'#\s{2,}#'					=> ' '		// Reduce the remaining multiple whitespace characters to a single space
+			);
+		}
+		else
+		{
+			$patterns = array(
+				'#/\*.*(?=\*/)\*/#s'	=> '',		// Remove /* block comments */
+				'#\n?//[^\n]*#'		=> '',		// Remove // line comments
+				'#\s*([^\w.\#%])\s*#U'	=> '$1',	// Remove spaces following and preceeding non-word characters, excluding dots, hashes and the percent sign
+				'#\s{2,}#'		=> ' '		// Reduce the remaining multiple space characters to a single space
+			);
+		}
+
+		$$varname = preg_replace(array_keys($patterns), array_values($patterns), $$varname);
+
+		// Glue back JS quoted strings
+		if ($type === 'js')
+		{
+			$js_code += $js_literals;
+			ksort($js_code);
+			$output = implode($js_code);
+			unset($js_code, $js_literals, $varname, $patterns);
 		}
 
-		// Put the opening and closing tags back if applicable
-		return isset($open_tag)
-			? $open_tag.$output.$closing_tag
+		return is_array($tags)
+			? $tags['open'].$output.$tags['close']
 			: $output;
 	}