<?php
	# Mantis - a php based bugtracking system
	# Copyright (C) 2000 - 2002  Kenzaburo Ito - kenito@300baud.org
	# Copyright (C) 2002 - 2004  Mantis Team   - mantisbt-dev@lists.sourceforge.net
	# This program is distributed under the terms and conditions of the GPL
	# See the README and LICENSE files for details

	# --------------------------------------------------------
	# $Id: compress_api.php,v 1.16 2005/02/12 20:01:10 jlatour Exp $
	# --------------------------------------------------------

	### Compression API ###

	# Starts the buffering/compression (only if the compression option is ON)
	# This method should be called after all possible re-directs and
	#  access level checks.

	# This variable is used internally.  It is not used for configuration
	$g_compression_started = false;

	# ----------------
	# Check if compression should be enabled.
	function compress_is_enabled() {
		global $g_compression_started;

		#@@@ temporarily disable compression when using IIS because of
		#   issue #2953
		return ( $g_compression_started &&
				ON == config_get( 'compress_html' ) &&
				OFF == config_get( 'use_iis' )  &&
				( 'ob_gzhandler' != ini_get('output_handler') ) &&
				extension_loaded( 'zlib' ) &&
				!ini_get('zlib.output_compression') );
	}

	# ----------------
	# Output Buffering handler that either compresses the buffer or just
	#  returns it, depending on the return value of compress_is_enabled()
	function compress_handler( $p_buffer, $p_mode ) {
		if ( compress_is_enabled() ) {
			return ob_gzhandler( $p_buffer, $p_mode );
		} else {
			return $p_buffer;
		}
	}

	# ----------------
	# Enable output buffering with compression.
	function compress_enable() {
		global $g_compression_started;

		$g_compression_started = true;
	}

	# ----------------
	# Disable output buffering with compression.
	function compress_disable() {
		global $g_compression_started;

		$g_compression_started = false;
	}
?>
