00001 <?php
00021 function smarty_function_math($params, &$smarty)
00022 {
00023
00024 if (empty($params['equation'])) {
00025 $smarty->trigger_error("math: missing equation parameter");
00026 return;
00027 }
00028
00029 $equation = $params['equation'];
00030
00031
00032 if (substr_count($equation,"(") != substr_count($equation,")")) {
00033 $smarty->trigger_error("math: unbalanced parenthesis");
00034 return;
00035 }
00036
00037
00038 preg_match_all("!(?:0x[a-fA-F0-9]+)|([a-zA-Z][a-zA-Z0-9_]+)!",$equation, $match);
00039 $allowed_funcs = array('int','abs','ceil','cos','exp','floor','log','log10',
00040 'max','min','pi','pow','rand','round','sin','sqrt','srand','tan');
00041
00042 foreach($match[1] as $curr_var) {
00043 if ($curr_var && !in_array($curr_var, array_keys($params)) && !in_array($curr_var, $allowed_funcs)) {
00044 $smarty->trigger_error("math: function call $curr_var not allowed");
00045 return;
00046 }
00047 }
00048
00049 foreach($params as $key => $val) {
00050 if ($key != "equation" && $key != "format" && $key != "assign") {
00051
00052 if (strlen($val)==0) {
00053 $smarty->trigger_error("math: parameter $key is empty");
00054 return;
00055 }
00056 if (!is_numeric($val)) {
00057 $smarty->trigger_error("math: parameter $key: is not numeric");
00058 return;
00059 }
00060 $equation = preg_replace("/\b$key\b/",$val, $equation);
00061 }
00062 }
00063
00064 eval("\$smarty_math_result = ".$equation.";");
00065
00066 if (empty($params['format'])) {
00067 if (empty($params['assign'])) {
00068 return $smarty_math_result;
00069 } else {
00070 $smarty->assign($params['assign'],$smarty_math_result);
00071 }
00072 } else {
00073 if (empty($params['assign'])){
00074 printf($params['format'],$smarty_math_result);
00075 } else {
00076 $smarty->assign($params['assign'],sprintf($params['format'],$smarty_math_result));
00077 }
00078 }
00079 }
00080
00081
00082
00083 ?>