<?php
/**
* Smarty plugin
* This plugin is only for Smarty2 BC
*
* @package Smarty
* @subpackage PluginsFunction
*/
/**
* Smarty {math} function plugin
* Type: function<br>
* Name: math<br>
* Purpose: handle math computations in template
*
* @link http://www.smarty.net/manual/en/language.function.math.php {math}
* (Smarty online manual)
* @author Monte Ohrt <monte at ohrt dot com>
*
* @param array $params parameters
* @param Smarty_Internal_Template $template template object
*
* @return string|null
*/
function smarty_function_math($params, $template)
{
static $_allowed_funcs =
array('int' => true, 'abs' => true, 'ceil' => true, 'cos' => true, 'exp' => true, 'floor' => true,
'log' => true, 'log10' => true, 'max' => true, 'min' => true, 'pi' => true, 'pow' => true, 'rand' => true,
'round' => true, 'sin' => true, 'sqrt' => true, 'srand' => true, 'tan' => true);
// be sure equation parameter is present
if (empty($params[ 'equation' ])) {
trigger_error("math: missing equation parameter", E_USER_WARNING);
return;
}
$equation = $params[ 'equation' ];
// make sure parenthesis are balanced
if (substr_count($equation, "(") != substr_count($equation, ")")) {
trigger_error("math: unbalanced parenthesis", E_USER_WARNING);
return;
}
// disallow backticks
if (strpos($equation, '`') !== false) {
trigger_error("math: backtick character not allowed in equation", E_USER_WARNING);
return;
}
// also disallow dollar signs
if (strpos($equation, '$') !== false) {
trigger_error("math: dollar signs not allowed in equation", E_USER_WARNING);
return;
}
// match all vars in equation, make sure all are passed
preg_match_all('!(?:0x[a-fA-F0-9]+)|([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)!', $equation, $match);
foreach ($match[ 1 ] as $curr_var) {
if ($curr_var && !isset($params[ $curr_var ]) && !isset($_allowed_funcs[ $curr_var ])) {
trigger_error("math: function call $curr_var not allowed", E_USER_WARNING);
return;
}
}
foreach ($params as $key => $val) {
if ($key != "equation" && $key != "format" && $key != "assign") {
// make sure value is not empty
if (strlen($val) == 0) {
trigger_error("math: parameter $key is empty", E_USER_WARNING);
return;
}
if (!is_numeric($val)) {
trigger_error("math: parameter $key: is not numeric", E_USER_WARNING);
return;
}
$equation = preg_replace("/\b$key\b/", " \$params['$key'] ", $equation);
}
}
$smarty_math_result = null;
eval("\$smarty_math_result = " . $equation . ";");
if (empty($params[ 'format' ])) {
if (empty($params[ 'assign' ])) {
return $smarty_math_result;
} else {
$template->assign($params[ 'assign' ], $smarty_math_result);
}
} else {
if (empty($params[ 'assign' ])) {
printf($params[ 'format' ], $smarty_math_result);
} else {
$template->assign($params[ 'assign' ], sprintf($params[ 'format' ], $smarty_math_result));
}
}
}