runff 1.0 commit

lib/SimpleSAML/XML/Errors.php

@@ -0,0 +1,140 @@
+<?php
+
+/**
+ * This class defines an interface for accessing errors from the XML library.
+ *
+ * In PHP versions which doesn't support accessing error information, this class
+ * will hide that, and pretend that no errors were logged.
+ *
+ * @author Olav Morken, UNINETT AS.
+ * @package SimpleSAMLphp
+ */
+
+namespace SimpleSAML\XML;
+
+use LibXMLError;
+
+class Errors
+{
+
+    /**
+     * @var array This is an stack of error logs. The topmost element is the one we are currently working on.
+     */
+    private static $errorStack = array();
+
+    /**
+     * @var bool This is the xml error state we had before we began logging.
+     */
+    private static $xmlErrorState;
+
+
+    /**
+     * Append current XML errors to the current stack level.
+     */
+    private static function addErrors()
+    {
+        $currentErrors = libxml_get_errors();
+        libxml_clear_errors();
+
+        $level = count(self::$errorStack) - 1;
+        self::$errorStack[$level] = array_merge(self::$errorStack[$level], $currentErrors);
+    }
+
+
+    /**
+     * Start error logging.
+     *
+     * A call to this function will begin a new error logging context. Every call must have
+     * a corresponding call to end().
+     */
+    public static function begin()
+    {
+
+        // Check whether the error access functions are present
+        if (!function_exists('libxml_use_internal_errors')) {
+            return;
+        }
+
+        if (count(self::$errorStack) === 0) {
+            // No error logging is currently in progress. Initialize it.
+            self::$xmlErrorState = libxml_use_internal_errors(true);
+            libxml_clear_errors();
+        } else {
+            /* We have already started error logging. Append the current errors to the
+             * list of errors in this level.
+             */
+            self::addErrors();
+        }
+
+        // Add a new level to the error stack
+        self::$errorStack[] = array();
+    }
+
+
+    /**
+     * End error logging.
+     *
+     * @return array  An array with the LibXMLErrors which has occurred since begin() was called.
+     */
+    public static function end()
+    {
+
+        // Check whether the error access functions are present
+        if (!function_exists('libxml_use_internal_errors')) {
+            // Pretend that no errors occurred
+            return array();
+        }
+
+        // Add any errors which may have occurred
+        self::addErrors();
+
+
+        $ret = array_pop(self::$errorStack);
+
+        if (count(self::$errorStack) === 0) {
+            // Disable our error logging and restore the previous state
+            libxml_use_internal_errors(self::$xmlErrorState);
+        }
+
+        return $ret;
+    }
+
+
+    /**
+     * Format an error as a string.
+     *
+     * This function formats the given LibXMLError object as a string.
+     *
+     * @param \LibXMLError $error  The LibXMLError which should be formatted.
+     * @return string  A string representing the given LibXMLError.
+     */
+    public static function formatError($error)
+    {
+        assert($error instanceof LibXMLError);
+        return 'level=' . $error->level . ',code='  . $error->code . ',line=' . $error->line . ',col=' . $error->column .
+            ',msg=' . trim($error->message);
+    }
+
+
+    /**
+     * Format a list of errors as a string.
+     *
+     * This fucntion takes an array of LibXMLError objects and creates a string with all the errors.
+     * Each error will be separated by a newline, and the string will end with a newline-character.
+     *
+     * @param array $errors  An array of errors.
+     * @return string  A string representing the errors. An empty string will be returned if there were no
+     *          errors in the array.
+     */
+    public static function formatErrors($errors)
+    {
+        assert(is_array($errors));
+
+        $ret = '';
+        foreach ($errors as $error) {
+            $ret .= self::formatError($error) . "\n";
+        }
+
+        return $ret;
+    }
+}