egroupware/phpgwapi/inc/common_functions.inc.php

<?php
	 /**************************************************************************\
	 * eGroupWare API - commonly used functions included by eGW AND setup       *
	 * The file was originaly written by Dan Kuykendall <seek3r@phpgroupware.org> *
	 * and Joseph Engo <jengo@phpgroupware.org>                                 *
	 * Copyright (C) 2000, 2001 Dan Kuykendall                                  *
	 * -------------------------------------------------------------------------*
	 * This library is part of the eGroupWare API                               *
	 * http://www.egroupware.org                                                *
	 * ------------------------------------------------------------------------ *
	 * This library is free software; you can redistribute it and/or modify it  *
	 * under the terms of the GNU Lesser General Public License as published by *
	 * the Free Software Foundation; either version 2.1 of the License,         *
	 * or any later version.                                                    *
	 * This library is distributed in the hope that it will be useful, but      *
	 * WITHOUT ANY WARRANTY; without even the implied warranty of               *
	 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.                     *
	 * See the GNU Lesser General Public License for more details.              *
	 * You should have received a copy of the GNU Lesser General Public License *
	 * along with this library; if not, write to the Free Software Foundation,  *
	 * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA            *
	 \**************************************************************************/

	/* $Id$ */

	/****************************************************************************\
	 * Direct functions which are not part of the API classes                    *
	 * because they are required to be available at the lowest level.            *
	 \***************************************************************************/

	/**
	 * Return the number of bytes of a string, independent of mbstring.func_overload
	 * AND the availability of mbstring
	 *
	 * @param string $str
	 * @return int
	 */
	function bytes($str)
	{
		static $func_overload;

		if (is_null($func_overload)) $func_overload = extension_loaded('mbstring') ? ini_get('mbstring.func_overload') : 0;

		return $func_overload & 2 ? mb_strlen($str,'ascii') : strlen($str);
	}

	/**
	 * @internal Not to be used directly. Should only be used by print_debug()
	 */
	function print_debug_subarray($array)
	{
		foreach($array as $key => $value)
		{
			if (is_array($value))
			{
				$vartypes[$key] = print_debug_subarray($value);
			}
			else
			{
				$vartypes[$key] = gettype($value);
			}
		}
		return $vartypes;
	}

	/**
	 * print debug data only when debugging mode is turned on.
	 *
	 * @author seek3r
	 * This function is used to debugging data.
	 * print_debug('this is some debugging data',$somevar);
	 */
	function print_debug($message,$var = 'messageonly',$part = 'app', $level = 3)
	{
		if (($part == 'app' && DEBUG_APP == True) || ($part == 'api' && DEBUG_API == True))
		{
			if (!defined('DEBUG_OUTPUT'))
			{
				define('DEBUG_OUTPUT', 1);
			}
			if ($level >= DEBUG_LEVEL)
			{
				if (!is_array($var))
				{
					if ($var != 'messageonly')
					{
						if (!DEBUG_DATATYPES)
						{
							$output = "$message\n$var";
						}
						else
						{
							$output = "$message\n$var is a ".gettype($var);
						}
					}
					else
					{
						$output = $message;
					}

					/* Bit 1 means to output to screen */
					if (!!(DEBUG_OUTPUT & 1))
					{
						echo "$output<br>\n";
					}
					/* Bit 2 means to output to sql */
					if (!!(DEBUG_OUTPUT & 2))
					{
						/* Need to flesh this out still. I dont have a table to dump this in yet.*/
						/* So the SQL statement will go here*/
					}

					/* Example of how this can be extended to output to other locations as well. This example uses a COM object */
					/*
					if (!!(DEBUG_OUTPUT & 32))
					{
						$obj_debug =& new COM('Some_COM_App.Class','localhost');
						if (is_object($obj_debug))
						{
							$DebugMessage_return = $obj_debug->DebugMessage($output);
						}
					}
					*/
				}
				else
				{
					if (floor(phpversion()) > 3 && !!(DEBUG_OUTPUT & 2))
					{
						ob_start();
					}
					echo "<pre>\n$message\n";
					print_r($var);
					if (DEBUG_DATATYPES)
					{
//						while(list($key, $value) = each($var))
						foreach($var as $key => $value)
						{
							if (is_array($value))
							{
								$vartypes[$key] = print_debug_subarray($value);
							}
							else
							{
								$vartypes[$key] = gettype($value);
							}
						}
						echo "Data Types:\n";
						print_r($vartypes);
					}
					echo "\n<pre>\n";
					if (floor(phpversion()) > 3 && !!(DEBUG_OUTPUT & 2))
					{
						$output .= ob_get_contents();
						ob_end_clean();
						/* Need to flesh this out still. I dont have a table to dump this in yet.*/
						/* So the SQL statement will go here*/
						if (!!(DEBUG_OUTPUT & 1))
						{
							echo "$output<br>\n";
						}
					}
				}
			}
		}
	}

	/**
	  * Allows for array and direct function params as well as sanatization.
	  *
	  * @author seek3r
	  * This function is used to validate param data as well as offer flexible function usage.
	  *
		function somefunc()
		{
			$expected_args[0] = Array('name'=>'fname','default'=>'joe', 'type'=>'string');
			$expected_args[1] = Array('name'=>'mname','default'=>'hick', 'type'=>'string');
			$expected_args[2] = Array('name'=>'lname','default'=>'bob', 'type'=>'string');
			$recieved_args = func_get_args();
			$args = safe_args($expected_args, $recieved_args,__LINE__,__FILE__);
			echo 'Full name: '.$args['fname'].' '.$args['fname'].' '.$args['lname'].'<br>';
			//default result would be:
			// Full name: joe hick bob<br>
		}

		Using this it is possible to use the function in any of the following ways
		somefunc('jack','city','brown');
		or
		somefunc(array('fname'=>'jack','mname'=>'city','lname'=>'brown'));
		or
		somefunc(array('lname'=>'brown','fname'=>'jack','mname'=>'city'));

		For the last one, when using named params in an array you dont have to follow any order
		All three would result in - Full name: jack city brown<br>

		When you use this method of handling params you can secure your functions as well offer
		flexibility needed for both normal use and web services use.
		If you have params that are required just set the default as ##REQUIRED##
		Users of your functions can also use ##DEFAULT## to use your default value for a param
		when using the standard format like this:
		somefunc('jack','##DEFAULT##','brown');
		This would result in - Full name: jack hick brown<br>
		Its using the default value for the second param.
		Of course if you have the second param as a required field it will fail to work.
	 */
	function safe_args($expected, $recieved, $line='??', $file='??')
	{
		/* This array will contain all the required fields */
		$required = Array();

		/* This array will contain all types for sanatization checking */
		/* only used when an array is passed as the first arg          */
		$types = Array();

		/* start by looping thru the expected list and set params with */
		/* the default values                                          */
		$num = count($expected);
		for ($i = 0; $i < $num; $i++)
		{
			$args[$expected[$i]['name']] = $expected[$i]['default'];
			if ($expected[$i]['default'] === '##REQUIRED##')
			{
				$required[$expected[$i]['name']] = True;
			}
			$types[$expected[$i]['name']] = $expected[$i]['type'];
		}

		/* Make sure they passed at least one param */
		if(count($recieved) != 0)
		{
			/* if used as standard function we loop thru and set by position */
			if(!is_array($recieved[0]))
			{
			for ($i = 0; $i < $num; $i++)
				{
					if(isset($recieved[$i]) && $recieved[$i] !== '##DEFAULT##')
					{
						if(sanitize($recieved[$i],$expected[$i]['type']))
						{
							$args[$expected[$i]['name']] = $recieved[$i];
							unset($required[$expected[$i]['name']]);
						}
						else
						{
							echo 'Fatal Error: Invalid paramater type for '.$expected[$i]['name'].' on line '.$line.' of '.$file.'<br>';
							exit;
						}
					}
				}
			}
			/* if used as standard function we loop thru and set by position */
			else
			{
				for ($i = 0; $i < $num; $i++)
				{
					$types[$expected[$i]['name']] = $expected[$i]['type'];
				}
				while(list($key,$val) = each($recieved[0]))
				{
					if($val !== '##DEFAULT##')
					{
						if(sanitize($val,$types[$key]) == True)
						{
							$args[$key] = $val;
							unset($required[$key]);
						}
						else
						{
							echo 'Fatal Error: Invalid paramater type for '.$key.' on line '.$line.' of '.$file.'<br>';
							exit;
						}
					}
				}
			}
		}
		if(count($required) != 0)
		{
			while (list($key) = each($required))
			{
				echo 'Fatal Error: Missing required paramater '.$key.' on line '.$line.' of '.$file.'<br>';
			}
			exit;
		}
		return $args;
	}

	/**
	 * Validate data.
	 *
	 * @author seek3r
	 * This function is used to validate input data.
	 * sanitize('number',$somestring);
	 */
	function sanitize($string,$type)
	{
		switch ($type)
		{
			case 'bool':
				if ($string == 1 || $string == 0)
				{
					return True;
				}
				break;
			case 'isprint':
				$length = strlen($string);
				$position = 0;
				while ($length > $position)
				{
					$char = substr($string, $position, 1);
					if ($char < ' ' || $char > '~')
					{
						return False;
					}
					$position = $position + 1;
				}
				return True;
				break;
			case 'alpha':
				if (preg_match("/^[a-z]+$/i", $string))
				{
					return True;
				}
				break;
			case 'number':
				if (preg_match("/^[0-9]+$/i", $string))
				{
					return True;
				}
				break;
			case 'alphanumeric':
				if (preg_match("/^[a-z0-9 -._]+$/i", $string))
				{
					return True;
				}
				break;
			case 'string':
				if (preg_match("/^[a-z]+$/i", $string))
				{
					return True;
				}
				break;
			case 'ip':
				if (eregi("^[0-9]{1,3}(\.[0-9]{1,3}){3}$",$string))
				{
					$octets = split('\.',$string);
					for ($i=0; $i != count($octets); $i++)
					{
						if ($octets[$i] < 0 || $octets[$i] > 255)
						{
							return False;
						}
					}
					return True;
				}
				return False;
				break;
			case 'file':
				if (preg_match("/^[a-z0-9_]+\.+[a-z]+$/i", $string))
				{
					return True;
				}
				break;
			case 'email':
				if (eregi("^([[:alnum:]_%+=.-]+)@([[:alnum:]_.-]+)\.([a-z]{2,3}|[0-9]{1,3})$",$string))
				{
					return True;
				}
				break;
			case 'password':
				$password_length = strlen($string);
				$password_numbers = Array('0','1','2','3','4','5','6','7','8','9');
				$password_special_chars = Array(' ','~','`','!','@','#','$','%','^','&','*','(',')','_','+','-','=','{','}','|','[',']',"\\",':','"',';',"'",'<','>','?',',','.','/');

				if(@isset($GLOBALS['egw_info']['server']['pass_min_length']) && is_int($GLOBALS['egw_info']['server']['pass_min_length']) && $GLOBALS['egw_info']['server']['pass_min_length'] > 1)
				{
					$min_length = $GLOBALS['egw_info']['server']['pass_min_length'];
				}
				else
				{
					$min_length = 1;
				}

				if(@isset($GLOBALS['egw_info']['server']['pass_require_non_alpha']) && $GLOBALS['egw_info']['server']['pass_require_non_alpha'] == True)
				{
					$pass_verify_non_alpha = False;
				}
				else
				{
					$pass_verify_non_alpha = True;
				}

				if(@isset($GLOBALS['egw_info']['server']['pass_require_numbers']) && $GLOBALS['egw_info']['server']['pass_require_numbers'] == True)
				{
					$pass_verify_num = False;
				}
				else
				{
					$pass_verify_num = True;
				}

				if(@isset($GLOBALS['egw_info']['server']['pass_require_special_char']) && $GLOBALS['egw_info']['server']['pass_require_special_char'] == True)
				{
					$pass_verify_special_char = False;
				}
				else
				{
					$pass_verify_special_char = True;
				}

				if ($password_length >= $min_length)
				{
					for ($i=0; $i != $password_length; $i++)
					{
						$cur_test_string = substr($string, $i, 1);
						if (in_array($cur_test_string, $password_numbers) || in_array($cur_test_string, $password_special_chars))
						{
							$pass_verify_non_alpha = True;
							if (in_array($cur_test_string, $password_numbers))
							{
								$pass_verify_num = True;
							}
							elseif (in_array($cur_test_string, $password_special_chars))
							{
								$pass_verify_special_char = True;
							}
						}
					}

					if ($pass_verify_num == False)
					{
						$GLOBALS['egw_info']['flags']['msgbox_data']['Password requires at least one non-alpha character']=False;
					}

					if ($pass_verify_num == False)
					{
						$GLOBALS['egw_info']['flags']['msgbox_data']['Password requires at least one numeric character']=False;
					}

					if ($pass_verify_special_char == False)
					{
						$GLOBALS['egw_info']['flags']['msgbox_data']['Password requires at least one special character (non-letter and non-number)']=False;
					}

					if ($pass_verify_num == True && $pass_verify_special_char == True)
					{
						return True;
					}
					return False;
				}
				$GLOBALS['egw_info']['flags']['msgbox_data']['Password must be at least '.$min_length.' characters']=False;
				return False;
				break;
			case 'any':
				return True;
				break;
			default :
				if (isset($GLOBALS['egw_info']['server']['sanitize_types'][$type]['type']))
				{
					if ($GLOBALS['egw_info']['server']['sanitize_types'][$type]['type']($GLOBALS['egw_info']['server']['sanitize_types'][$type]['string'], $string))
					{
						return True;
					}
				}
				return False;
		}
	}

	function reg_var($varname, $method='any', $valuetype='alphanumeric',$default_value='',$register=True)
	{
		if($method == 'any' || $method == array('any'))
		{
			$method = Array('POST','GET','COOKIE','SERVER','FILES','GLOBAL','DEFAULT');
		}
		elseif(!is_array($method))
		{
			$method = Array($method);
		}
		$cnt = count($method);
		for($i=0;$i<$cnt;$i++)
		{
			switch(strtoupper($method[$i]))
			{
				case 'DEFAULT':
					if($default_value)
					{
						$value = $default_value;
						$i = $cnt+1; /* Found what we were looking for, now we end the loop */
					}
					break;
				case 'GLOBAL':
					if(@isset($GLOBALS[$varname]))
					{
						$value = $GLOBALS[$varname];
						$i = $cnt+1;
					}
					break;
				case 'POST':
				case 'GET':
				case 'COOKIE':
				case 'SERVER':
					if(phpversion() >= '4.1.0')
					{
						$meth = '_'.strtoupper($method[$i]);
					}
					else
					{
						$meth = 'HTTP_'.strtoupper($method[$i]).'_VARS';
					}
					if(@isset($GLOBALS[$meth][$varname]))
					{
						$value = $GLOBALS[$meth][$varname];
						$i = $cnt+1;
					}
					if(get_magic_quotes_gpc() && isset($value))
					{
						// we need to stripslash 3 levels of arrays
						// because of the password function in preferences
						// it's named ['user']['variablename']['pw']
						// or something like this in projects
						// $values['budgetBegin']['1']['year']
						if(@is_array($value))
						{
							/* stripslashes on the first level of array values */
							foreach($value as $name => $val)
							{
								if(@is_array($val))
								{
									foreach($val as $name2 => $val2)
									{
										if(@is_array($val2))
										{
											foreach($val2 as $name3 => $val3)
											{
												$value[$name][$name2][$name3] = stripslashes($val3);
											}
										}
										else
										{
											$value[$name][$name2] = stripslashes($val2);
										}
									}
								}
								else
								{
									$value[$name] = stripslashes($val);
								}
							}
						}
						else
						{
							/* stripslashes on this (string) */
							$value = stripslashes($value);
						}
					}
					break;
				case 'FILES':
					if(phpversion() >= '4.1.0')
					{
						$meth = '_FILES';
					}
					else
					{
						$meth = 'HTTP_POST_FILES';
					}
					if(@isset($GLOBALS[$meth][$varname]))
					{
						$value = $GLOBALS[$meth][$varname];
						$i = $cnt+1;
					}
					break;
				default:
					if(@isset($GLOBALS[strtoupper($method[$i])][$varname]))
					{
						$value = $GLOBALS[strtoupper($method[$i])][$varname];
						$i = $cnt+1;
					}
					break;
			}
		}

		if (@!isset($value))
		{
			$value = $default_value;
		}

		if (@!is_array($value))
		{
			if ($value == '')
			{
				$result = $value;
			}
			else
			{
				if (sanitize($value,$valuetype) == 1)
				{
					$result = $value;
				}
				else
				{
					$result = $default_value;
				}
			}
		}
		else
		{
			reset($value);
			while(list($k, $v) = each($value))
			{
				if ($v == '')
				{
					$result[$k] = $v;
				}
				else
				{
					if (is_array($valuetype))
					{
						$vt = $valuetype[$k];
					}
					else
					{
						$vt = $valuetype;
					}

					if (sanitize($v,$vt) == 1)
					{
						$result[$k] = $v;
					}
					else
					{
						if (is_array($default_value))
						{
							$result[$k] = $default_value[$k];
						}
						else
						{
							$result[$k] = $default_value;
						}
					}
				}
			}
		}
		if($register)
		{
			$GLOBALS['egw_info'][$GLOBALS['egw_info']['flags']['currentapp']][$varname] = $result;
		}
		return $result;
	}

	/**
	 * retrieve a value from either a POST, GET, COOKIE, SERVER or from a class variable.
	 *
	 * @author skeeter
	 * This function is used to retrieve a value from a user defined order of methods.
	 * $this->id = get_var('id',array('HTTP_POST_VARS'||'POST','HTTP_GET_VARS'||'GET','HTTP_COOKIE_VARS'||'COOKIE','GLOBAL','DEFAULT'));
	 * @param $variable name
	 * @param $method ordered array of methods to search for supplied variable
	 * @param $default_value (optional)
	 */
	function get_var($variable,$method='any',$default_value='')
	{
		if(!@is_array($method))
		{
			$method = array($method);
		}
		return reg_var($variable,$method,'any',$default_value,False);
	}

	/**
	 * Load a class and include the class file if not done so already.
	 *
	 * This function is used to create an instance of a class, and if the class file has not been included it will do so.
	 * $GLOBALS['egw']->acl =& CreateObject('phpgwapi.acl');
	 *
	 * @author RalfBecker@outdoor-training.de
	 * @param $classname name of class
	 * @param $p1,$p2,... class parameters (all optional)
	 * @return object reference to an object
	 */
	function &CreateObject($class)
	{
		list($appname,$classname) = explode('.',$class);

		if ($classname == 'datetime') $classname = 'egw_datetime';	// php5.2 fix

		include_once(EGW_INCLUDE_ROOT.'/'.$appname.'/inc/class.'.$classname.'.inc.php');

		if (class_exists($classname))
		{
			$args = func_get_args();
			if(count($args) == 1)
			{
				$obj =& new $classname;
			}
			else
			{
				$code = '$obj =& new ' . $classname . '(';
				foreach($args as $n => $arg)
				{
					if ($n)
					{
						$code .= ($n > 1 ? ',' : '') . '$args[' . $n . ']';
					}
				}
				$code .= ');';
				eval($code);
			}
		}
		if (!is_object($obj))
		{
			echo "<p>CreateObject('$class'): Cant instanciate class!!!<br />\n".function_backtrace(1)."</p>\n";
		}
		return $obj;
	}

	/**
	 * Execute a function with multiple arguments
	 * We take object $GLOBALS[classname] from class if exists
	 *
	 * @param string app.class.method method to execute
	 * @example ExecObject('etemplates.so_sql.search',$criteria,$key_only,...);
	 * @return mixed reference to returnvalue of the method
	 */
	function &ExecMethod2($acm)
	{
		list($app,$class,$method) = explode('.',$acm);
		if (!is_object($obj =& $GLOBALS[$class]))
		{
			$newobj = 1;
			$obj =& CreateObject($acm);
		}

		if (!method_exists($obj,$method))
		{
			echo "<p><b>".function_backtrace()."</b>: no methode '$method' in class '$class'</p>\n";
			return False;
		}

		$args = func_get_args();
		unset($args[0]);
		$code = '$return =& $obj->'.$method.'(';
		foreach	($args as $n => $arg)
		{
			if ($n)
			{
				$code .= ($n > 1 ? ',' : '') . '$args[' . $n . ']';
			}
		}		
		
		eval($code.');');
		if($newobj) unset($obj);
		return $return;
	}

	/**
	 * Execute a function, and load a class and include the class file if not done so already.
	 *
	 * This function is used to create an instance of a class, and if the class file has not been included it will do so.
	 *
	 * @author seek3r
	 * @param $method to execute
	 * @param $functionparams function param should be an array
	 * @param $loglevel developers choice of logging level
	 * @param $classparams params to be sent to the contructor
	 * @return mixed returnvalue of method
	 */
	function ExecMethod($method, $functionparams = '_UNDEF_', $loglevel = 3, $classparams = '_UNDEF_')
	{
		/* Need to make sure this is working against a single dimensional object */
		$partscount = count(explode('.',$method)) - 1;
		if ($partscount == 2)
		{
			list($appname,$classname,$functionname) = explode(".", $method);
			if (!is_object($GLOBALS[$classname]))
			{
				// please note: no reference assignment (=&) here, as $GLOBALS is a reference itself!!!
				if ($classparams != '_UNDEF_' && ($classparams || $classparams != 'True'))
				{
					$GLOBALS[$classname] = CreateObject($appname.'.'.$classname, $classparams);
				}
				else
				{
					$GLOBALS[$classname] = CreateObject($appname.'.'.$classname);
				}
			}

			if (!method_exists($GLOBALS[$classname],$functionname))
			{
				echo "<p><b>".function_backtrace()."</b>: no methode '$functionname' in class '$classname'</p>\n";
				return False;
			}
			if ((is_array($functionparams) || $functionparams != '_UNDEF_') && ($functionparams || $functionparams != 'True'))
			{
				return $GLOBALS[$classname]->$functionname($functionparams);
			}
			else
			{
				return $GLOBALS[$classname]->$functionname();
			}
		}
		/* if the $method includes a parent class (multi-dimensional) then we have to work from it */
		elseif ($partscount >= 3)
		{
			$GLOBALS['methodparts'] = explode(".", $method);
			$classpartnum = $partscount - 1;
			$appname = $GLOBALS['methodparts'][0];
			$classname = $GLOBALS['methodparts'][$classpartnum];
			$functionname = $GLOBALS['methodparts'][$partscount];
			/* Now we clear these out of the array so that we can do a proper */
			/* loop and build the $parentobject */
			unset ($GLOBALS['methodparts'][0]);
			unset ($GLOBALS['methodparts'][$classpartnum]);
			unset ($GLOBALS['methodparts'][$partscount]);
			reset ($GLOBALS['methodparts']);
			$firstparent = 'True';
//			while (list ($key, $val) = each ($GLOBALS['methodparts']))
			foreach($GLOBALS['methodparts'] as $val)
			{
				if ($firstparent == 'True')
				{
					$parentobject = '$GLOBALS["'.$val.'"]';
					$firstparent = False;
				}
				else
				{
					$parentobject .= '->'.$val;
				}
			}
			unset($GLOBALS['methodparts']);
			$code = '$isobject = is_object('.$parentobject.'->'.$classname.');';
			eval ($code);
			if (!$isobject)
			{
				if ($classparams != '_UNDEF_' && ($classparams || $classparams != 'True'))
				{
					if (is_string($classparams))
					{
						eval($parentobject.'->'.$classname.' =& CreateObject("'.$appname.'.'.$classname.'", "'.$classparams.'");');
					}
					else
					{
						eval($parentobject.'->'.$classname.' =& CreateObject("'.$appname.'.'.$classname.'", '.$classparams.');');
					}
				}
				else
				{
					eval($parentobject.'->'.$classname.' =& CreateObject("'.$appname.'.'.$classname.'");');
				}
			}

			if ($functionparams != '_UNDEF_' && ($functionparams || $functionparams != 'True'))
			{
				eval('$returnval = '.$parentobject.'->'.$classname.'->'.$functionname.'('.$functionparams.');');
				return $returnval;
			}
			else
			{
				eval('$returnval = '.$parentobject.'->'.$classname.'->'.$functionname.'();');
				return $returnval;
			}
		}
		else
		{
			return "<p>ExecMethod('$method'): error in parts!<br />".function_backtrace()."</p>\n";
		}
	}

	/**
	  * duplicates the result of copying an object under php3/4 even when using php5
	  *
	  * This is critical when looping on db object output and updating or inserting to the database using a copy of the db object.  This was first added to GroupWhere
	  *
	  * @deprecated use $copy = clone($obj);
	  * @author milosch
	  * @param $a   - Source Object
	  * @param $b   - Target Object (copy)
	 */
	function copyobj($a,&$b)
	{
		if(floor(phpversion()) > 4)
		{
			$b = clone($a);
		}
		else
		{
			$b = $a;
		}
		return;
	}

	/**
	 * Return a properly formatted account_id.
	 *
	 * @author skeeter
	 * This function will return a properly formatted account_id. This can take either a name or an account_id as paramters. If a name is provided it will return the associated id.
	 * $account_id = get_account_id($accountid);
	 * @param int/string $account_id either a name or an id
	 * @param int/string $default_id either a name or an id
	 * @return int account_id
	 */
	function get_account_id($account_id = '',$default_id = '')
	{
		if (gettype($account_id) == 'integer')
		{
			return $account_id;
		}
		elseif ($account_id == '')
		{
			if ($default_id == '')
			{
				return (isset($GLOBALS['egw_info']['user']['account_id'])?$GLOBALS['egw_info']['user']['account_id']:0);
			}
			elseif (is_string($default_id))
			{
				return $GLOBALS['egw']->accounts->name2id($default_id);
			}
			return (int)$default_id;
		}
		elseif (is_string($account_id))
		{
			if($GLOBALS['egw']->accounts->exists((int)$account_id) == True)
			{
				return (int)$account_id;
			}
			else
			{
				return $GLOBALS['egw']->accounts->name2id($account_id);
			}
		}
	}

	/**
	 * sets the file system seperator depending on OS
	 *
	 * This is completely unnecessary, as you can use forward slashes in php under every OS -- RalfBecker 2005/11/09
	 *
	 * @return file system separator
	 */
	function filesystem_separator()
	{
		if(PHP_OS == 'Windows' || PHP_OS == 'OS/2' || PHP_OS == 'WINNT')
		{
			return '\\';
		}
		else
		{
			return '/';
		}
	}

	/**
	 * print an array or object as pre-formatted html
	 *
	 * @param mixed $array
	 * @param boolean $print=true print or return the content
	 * @return string if !$print
	 */
	function _debug_array($array,$print=True)
	{
		$output = '<pre>'.print_r($array,true)."</pre>\n";

		if ($print)
		{
			echo $output;
		}
		else
		{
			return $output;
		}
	}

	/**
	 * eGW version checking, is eGW version in $a < $b
	 *
	 * @param string $a	egw version number to check if less than $b
	 * @param string $b egw version number to check $a against
	 * @return boolean True if $a < $b
	 */
	function alessthanb($a,$b,$DEBUG=False)
	{
		$num = array('1st','2nd','3rd','4th');

		if ($DEBUG)
		{
			echo'<br>Input values: ' . 'A="'.$a.'", B="'.$b.'"';
		}
		$newa = str_replace('pre','.',$a);
		$newb = str_replace('pre','.',$b);
		$testa = explode('.',$newa);
		if(@$testa[1] == '')
		{
			$testa[1] = 0;
		}
		if(@$testa[3] == '')
		{
			$testa[3] = 0;
		}
		$testb = explode('.',$newb);
		if(@$testb[1] == '')
		{
			$testb[1] = 0;
		}
		if(@$testb[3] == '')
		{
			$testb[3] = 0;
		}
		$less = 0;

		for ($i=0;$i<count($testa);$i++)
		{
			if ($DEBUG) { echo'<br>Checking if '. (int)$testa[$i] . ' is less than ' . (int)$testb[$i] . ' ...'; }
			if ((int)$testa[$i] < (int)$testb[$i])
			{
				if ($DEBUG) { echo ' yes.'; }
				$less++;
				if ($i<3)
				{
					/* Ensure that this is definitely smaller */
					if ($DEBUG) { echo"  This is the $num[$i] octet, so A is definitely less than B."; }
					$less = 5;
					break;
				}
			}
			elseif((int)$testa[$i] > (int)$testb[$i])
			{
				if ($DEBUG) { echo ' no.'; }
				$less--;
				if ($i<2)
				{
					/* Ensure that this is definitely greater */
					if ($DEBUG) { echo"  This is the $num[$i] octet, so A is definitely greater than B."; }
					$less = -5;
					break;
				}
			}
			else
			{
				if ($DEBUG) { echo ' no, they are equal.'; }
				$less = 0;
			}
		}
		if ($DEBUG) { echo '<br>Check value is: "'.$less.'"'; }
		if ($less>0)
		{
			if ($DEBUG) { echo '<br>A is less than B'; }
			return True;
		}
		elseif($less<0)
		{
			if ($DEBUG) { echo '<br>A is greater than B'; }
			return False;
		}
		else
		{
			if ($DEBUG) { echo '<br>A is equal to B'; }
			return False;
		}
	}

	/**
	 * eGW version checking, is eGW version in $a > $b
	 *
	 * @param string $a eGW version number to check if more than $b
	 * @param string $b eGW version number to check check $a against
	 * @return boolean True if $a > $b
	 */
	function amorethanb($a,$b,$DEBUG=False)
	{
		$num = array('1st','2nd','3rd','4th');

		if ($DEBUG)
		{
			echo'<br>Input values: ' . 'A="'.$a.'", B="'.$b.'"';
		}
		$newa = str_replace('pre','.',$a);
		$newb = str_replace('pre','.',$b);
		$testa = explode('.',$newa);
		if($testa[3] == '')
		{
			$testa[3] = 0;
		}
		$testb = explode('.',$newb);
		if($testb[3] == '')
		{
			$testb[3] = 0;
		}
		$less = 0;

		for ($i=0;$i<count($testa);$i++)
		{
			if ($DEBUG) { echo'<br>Checking if '. (int)$testa[$i] . ' is more than ' . (int)$testb[$i] . ' ...'; }
			if ((int)$testa[$i] > (int)$testb[$i])
			{
				if ($DEBUG) { echo ' yes.'; }
				$less++;
				if ($i<3)
				{
					/* Ensure that this is definitely greater */
					if ($DEBUG) { echo"  This is the $num[$i] octet, so A is definitely greater than B."; }
					$less = 5;
					break;
				}
			}
			elseif((int)$testa[$i] < (int)$testb[$i])
			{
				if ($DEBUG) { echo ' no.'; }
				$less--;
				if ($i<2)
				{
					/* Ensure that this is definitely smaller */
					if ($DEBUG) { echo"  This is the $num[$i] octet, so A is definitely less than B."; }
					$less = -5;
					break;
				}
			}
			else
			{
				if ($DEBUG) { echo ' no, they are equal.'; }
				$less = 0;
			}
		}
		if ($DEBUG) { echo '<br>Check value is: "'.$less.'"'; }
		if ($less>0)
		{
			if ($DEBUG) { echo '<br>A is greater than B'; }
			return True;
		}
		elseif($less<0)
		{
			if ($DEBUG) { echo '<br>A is less than B'; }
			return False;
		}
		else
		{
			if ($DEBUG) { echo '<br>A is equal to B'; }
			return False;
		}
	}

	/**
	 * prepend a prefix to an array of table names
	 *
	 * @author Adam Hull (aka fixe) - No copyright claim
	 * @param	$prefix	the string to be prepended
	 * @param	$tables	and array of tables to have the prefix prepended to
	 * @return array of table names with the prefix prepended
	 */
	function prepend_tables_prefix($prefix,$tables)
	{
		foreach($tables as $key => $value)
		{
			$tables[$key] = $prefix.$value;
		}
		return $tables;
	}

	/**
	 * backtrace of the calling functions for php4.3+ else menuaction/scriptname
	 *
	 * @author RalfBecker-AT-outdoor-training.de
	 * @param int $remove=0 number of levels to remove
	 * @return string function-names separated by slashes (beginning with the calling function not this one)
	 */
	function function_backtrace($remove=0)
	{
		if (function_exists('debug_backtrace'))
		{
			$backtrace = debug_backtrace();
			//echo "function_backtrace($remove)<pre>".print_r($backtrace,True)."</pre>\n";
			foreach($backtrace as $level)
			{
				if ($remove-- < 0)
				{
					$ret[] = (isset($level['class'])?$level['class'].'::':'').$level['function'].
						(!$level['class'] && !is_object($level['args'][0]) && $level['function'] != 'unserialize' ?
						'('.substr(str_replace(EGW_SERVER_ROOT,'',$level['args'][0]),0,64).')' : '');
				}
			}
			if (is_array($ret))
			{
				return implode(' / ',$ret);
			}
		}
		return $_GET['menuaction'] ? $_GET['menuaction'] : str_replace(EGW_SERVER_ROOT,'',$_SERVER['SCRIPT_FILENAME']);
	}

	/**
	 * check $_REQUEST data for XSS, vars containing script tags are moved to $GLOBALS['egw_unset_vars']
	 *
	 * @internal
	 * @param array &$var reference of array to check
	 * @param string $name='' name of the array
	 */
	function _check_script_tag(&$var,$name='')
	{
		if (is_array($var))
		{
			foreach($var as $key => $val)
			{
				if (is_array($val))
				{
					_check_script_tag($var[$key],$name.'['.$key.']');
				}
				else
				{
					if (preg_match('/<\/?[^>]*(iframe|script|onabort|onblur|onchange|onclick|ondblclick|onerror|onfocus|onkeydown|onkeypress|onkeyup|onload|onmousedown|onmousemove|onmouseout|onmouseover|onmouseup|onreset|onselect|onsubmit|onunload|javascript)+[^>]*>/i',$val))
					{
						//echo "<p>*** _check_script_tag($name): unset(${name}[$key]) ***</p>\n";
						$GLOBALS['egw_unset_vars'][$name.'['.$key.']'] =& $var[$key];
						unset($var[$key]);
					}
				}
			}
			// in case some stupid old code expects the array-pointer to be at the start of the array
			reset($var);
		}
	}

	foreach(array('_GET','_POST','_REQUEST','HTTP_GET_VARS','HTTP_POST_VARS') as $n => $where)
	{
		$pregs = array(
			'order' => '/^[a-zA-Z0-9_,]*$/',
			'sort'  => '/^(ASC|DESC|asc|desc|0|1|2|3|4|5|6|7){0,1}$/',
		);
		foreach(array('order','sort') as $name)
		{
			if (isset($GLOBALS[$where][$name]) && !is_array($GLOBALS[$where][$name]) && !preg_match($pregs[$name],$GLOBALS[$where][$name]))
			{
				$GLOBALS[$where][$name] = '';
			}
		}
		// do the check for script-tags only for _GET and _POST or if we found something in _GET and _POST
		// speeds up the execusion a bit
		if (is_array($GLOBALS[$where]) && ($n < 2 || is_array($GLOBALS['egw_unset_vars'])))
		{
			_check_script_tag($GLOBALS[$where],$where);
		}
	}
	//if (is_array($GLOBALS['egw_unset_vars'])) { echo "egw_unset_vars=<pre>".htmlspecialchars(print_r($GLOBALS['egw_unset_vars'],true))."</pre>"; exit; }

	// neutralises register_globals On, which is not used by eGW
	// some code from the hardend php project: http://www.hardened-php.net/articles/PHPUG-PHP-Sicherheit-Parametermanipulationen.pdf
	if (ini_get('register_globals'))
	{
		function unregister_globals()
		{
			// protect against GLOBALS overwrite or setting egw_info
			if (isset($_REQUEST['GLOBALS']) || isset($_FILES['GLOBALS']) || isset($_REQUEST['egw_info']) || isset($_FILES['egw_info']))
			{
				die('GLOBALS overwrite detected!!!');
			}
			// unregister all globals
			$noUnset = array('GLOBALS','_GET','_POST','_COOKIE','_SERVER','_ENV','_FILES','xajax');
			foreach(array_unique(array_merge(
				array_keys($_GET),array_keys($_POST),array_keys($_COOKIE),array_keys($_SERVER),array_keys($_ENV),array_keys($_FILES),
				isset($_SESSION) && is_array($_SESSION) ? array_keys($_SESSION) : array())) as $k)
			{
				if (!in_array($k,$noUnset) && isset($GLOBALS[$k]))
				{
					unset($GLOBALS[$k]);
				}
			}
		}
		unregister_globals();
	}

	if(floor(phpversion()) <= 4)
	{
		/**
		 * clone function for php4, use as $new_obj = clone($old_obj);
		 */
		eval('
		function clone($obj)
		{
			return $obj;
		}
		');
	}

	if (!function_exists('lang'))	// setup declares an own version
	{
		/**
		 * function to handle multilanguage support
		 *
		 * @param string $key message in englich with %1, %2, ... placeholders
		 * @param string $vars=null multiple values to replace the placeholders
		 * @return string translated message with placeholders replaced
		 */
		function lang($key,$vars=null)
		{
			if(!is_array($vars))
			{
				$vars = func_get_args();
				array_shift($vars);	// remove $key
			}
			return $GLOBALS['egw']->translation->translate($key,$vars);
		}
	}
?>