Initial commit

core/template/plugins/function.math.php

@@ -0,0 +1,109 @@
+<?php
+/**
+ * Smarty plugin
+ * This plugin is only for Smarty2 BC
+ *
+ * @package    Smarty
+ * @subpackage PluginsFunction
+ */
+
+/**
+ * Smarty {math} function plugin
+ * Type:     function
+ * Name:     math
+ * 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;
+    }
+
+    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;
+            }
+        }
+    }
+
+    // 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, or missing parameter '{$curr_var}'", E_USER_WARNING);
+
+            return;
+        }
+    }
+
+    foreach ($params as $key => $val) {
+        if ($key !== 'equation' && $key !== 'format' && $key !== 'assign') {
+            $equation = preg_replace("/\b$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));
+        }
+    }
+}