lib/api/smarty/plugins/function.math.php

   1 <?php
   2 /**
   3  * Smarty plugin
   4  * This plugin is only for Smarty2 BC
   5  *
   6  * @package    Smarty
   7  * @subpackage PluginsFunction
   8  */
   9
  10 /**
  11  * Smarty {math} function plugin
  12  * Type:     function<br>
  13  * Name:     math<br>
  14  * Purpose:  handle math computations in template
  15  *
  16  * @link     http://www.smarty.net/manual/en/language.function.math.php {math}
  17  *           (Smarty online manual)
  18  * @author   Monte Ohrt <monte at ohrt dot com>
  19  *
  20  * @param array                    $params   parameters
  21  * @param Smarty_Internal_Template $template template object
  22  *
  23  * @return string|null
  24  */
  25 function smarty_function_math($params, $template)
  26 {
  27     static $_allowed_funcs = array(
  28         'int'  => true, 'abs' => true, 'ceil' => true, 'cos' => true, 'exp' => true, 'floor' => true,
  29         'log'  => true, 'log10' => true, 'max' => true, 'min' => true, 'pi' => true, 'pow' => true,
  30         'rand' => true, 'round' => true, 'sin' => true, 'sqrt' => true, 'srand' => true, 'tan' => true
  31     );
  32     // be sure equation parameter is present
  33     if (empty($params['equation'])) {
  34         trigger_error("math: missing equation parameter", E_USER_WARNING);
  35
  36         return;
  37     }
  38
  39     $equation = $params['equation'];
  40
  41     // make sure parenthesis are balanced
  42     if (substr_count($equation, "(") != substr_count($equation, ")")) {
  43         trigger_error("math: unbalanced parenthesis", E_USER_WARNING);
  44
  45         return;
  46     }
  47
  48     // match all vars in equation, make sure all are passed
  49     preg_match_all("!(?:0x[a-fA-F0-9]+)|([a-zA-Z][a-zA-Z0-9_]*)!", $equation, $match);
  50
  51     foreach ($match[1] as $curr_var) {
  52         if ($curr_var && !isset($params[$curr_var]) && !isset($_allowed_funcs[$curr_var])) {
  53             trigger_error("math: function call $curr_var not allowed", E_USER_WARNING);
  54
  55             return;
  56         }
  57     }
  58
  59     foreach ($params as $key => $val) {
  60         if ($key != "equation" && $key != "format" && $key != "assign") {
  61             // make sure value is not empty
  62             if (strlen($val) == 0) {
  63                 trigger_error("math: parameter $key is empty", E_USER_WARNING);
  64
  65                 return;
  66             }
  67             if (!is_numeric($val)) {
  68                 trigger_error("math: parameter $key: is not numeric", E_USER_WARNING);
  69
  70                 return;
  71             }
  72             $equation = preg_replace("/\b$key\b/", " \$params['$key'] ", $equation);
  73         }
  74     }
  75     $smarty_math_result = null;
  76     eval("\$smarty_math_result = " . $equation . ";");
  77
  78     if (empty($params['format'])) {
  79         if (empty($params['assign'])) {
  80             return $smarty_math_result;
  81         } else {
  82             $template->assign($params['assign'], $smarty_math_result);
  83         }
  84     } else {
  85         if (empty($params['assign'])) {
  86             printf($params['format'], $smarty_math_result);
  87         } else {
  88             $template->assign($params['assign'], sprintf($params['format'], $smarty_math_result));
  89         }
  90     }
  91 }