Compress script for CodeIgniter

ci_compress.php

function compress()
{
	ini_set("pcre.recursion_limit", "16777");
	$CI =& get_instance();
	$CI->benchmark->mark('compression_start');

	// Set output type
	$CI->output->set_header('Content-type: text/html; charset=utf-8');

	$buffer = $CI->output->get_output();
	$re = '%# Collapse whitespace everywhere but in blacklisted elements.
		(?>             # Match all whitespans other than single space.
		  [^\S ]\s*     # Either one [\t\r\n\f\v] and zero or more ws,
		| \s{2,}        # or two or more consecutive-any-whitespace.
		) # Note: The remaining regex consumes no text at all...
		(?=             # Ensure we are not in a blacklist tag.
		  [^<]*+        # Either zero or more non-"<" {normal*}
		  (?:           # Begin {(special normal*)*} construct
			<           # or a < starting a non-blacklist tag.
			(?!/?(?:textarea|pre|script)\b)
			[^<]*+      # more non-"<" {normal*}
		  )*+           # Finish "unrolling-the-loop"
		  (?:           # Begin alternation group.
			<           # Either a blacklist start tag.
			(?>textarea|pre|script)\b
		  | \z          # or end of file.
		  )             # End alternation group.
		)  # If we made it here, we are not in a blacklist tag.
		%Six';

	$new_buffer = preg_replace($re, " ", $buffer);

	// We are going to check if processing has working
	if ($new_buffer === null) {
		$new_buffer = $buffer;
	}
	$CI->output->set_output($new_buffer);
	$CI->benchmark->mark('compression_end');
	$CI->output->_display();

}