Merge branch 'w02_MDL-37286_m25_tracebuffer' of git://github.com/skodak/moodle

diff --combined lib/weblib.php
index a82d363,0b2caea..9b93a3a
--- 1/lib/weblib.php
--- 2/lib/weblib.php
+++ b/lib/weblib.php
@@@ -1578,21 -1578,8 +1578,21 @@@ function is_purify_html_necessary($text
  function purify_html($text, $options = array()) {
      global $CFG;
  
 -    $type = !empty($options['allowid']) ? 'allowid' : 'normal';
      static $purifiers = array();
 +    static $caches = array();
 +
 +    $type = !empty($options['allowid']) ? 'allowid' : 'normal';
 +
 +    if (!array_key_exists($type, $caches)) {
 +        $caches[$type] = cache::make('core', 'htmlpurifier', array('type' => $type));
 +    }
 +    $cache = $caches[$type];
 +
 +    $filteredtext = $cache->get($text);
 +    if ($filteredtext !== false) {
 +        return $filteredtext;
 +    }
 +
      if (empty($purifiers[$type])) {
  
          // make sure the serializer dir exists, it should be fine if it disappears later during cache reset
@@@ -1640,17 -1627,15 +1640,17 @@@
  
      $multilang = (strpos($text, 'class="multilang"') !== false);
  
 +    $filteredtext = $text;
      if ($multilang) {
 -        $text = preg_replace('/<span(\s+lang="([a-zA-Z0-9_-]+)"|\s+class="multilang"){2}\s*>/', '<span xxxlang="${2}">', $text);
 +        $filteredtext = preg_replace('/<span(\s+lang="([a-zA-Z0-9_-]+)"|\s+class="multilang"){2}\s*>/', '<span xxxlang="${2}">', $filteredtext);
      }
 -    $text = $purifier->purify($text);
 +    $filteredtext = $purifier->purify($filteredtext);
      if ($multilang) {
 -        $text = preg_replace('/<span xxxlang="([a-zA-Z0-9_-]+)">/', '<span lang="${1}" class="multilang">', $text);
 +        $filteredtext = preg_replace('/<span xxxlang="([a-zA-Z0-9_-]+)">/', '<span lang="${1}" class="multilang">', $filteredtext);
      }
 +    $cache->set($text, $filteredtext);
  
 -    return $text;
 +    return $filteredtext;
  }
  
  /**
@@@ -3159,7 -3144,8 +3159,8 @@@ EOT
   */
  abstract class progress_trace {
      /**
-      * Ouput an progress message in whatever format.
+      * Output an progress message in whatever format.
+      *
       * @param string $message the message to output.
       * @param integer $depth indent depth for this message.
       */
@@@ -3198,7 -3184,7 +3199,7 @@@ class null_progress_trace extends progr
   */
  class text_progress_trace extends progress_trace {
      /**
-      * Output the trace message
+      * Output the trace message.
       *
       * @param string $message
       * @param int $depth
@@@ -3218,7 -3204,7 +3219,7 @@@
   */
  class html_progress_trace extends progress_trace {
      /**
-      * Output the trace message
+      * Output the trace message.
       *
       * @param string $message
       * @param int $depth
@@@ -3280,6 -3266,150 +3281,150 @@@ class html_list_progress_trace extends 
      }
  }
  
+ /**
+  * This subclass of progress_trace outputs to error log.
+  *
+  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+  * @package moodlecore
+  */
+ class error_log_progress_trace extends progress_trace {
+     /** @var string log prefix */
+     protected $prefix;
+ 
+     /**
+      * Constructor.
+      * @param string $prefix optional log prefix
+      */
+     public function __construct($prefix = '') {
+         $this->prefix = $prefix;
+     }
+ 
+     /**
+      * Output the trace message.
+      *
+      * @param string $message
+      * @param int $depth
+      * @return void Output is sent to error log.
+      */
+     public function output($message, $depth = 0) {
+         error_log($this->prefix . str_repeat('  ', $depth) . $message);
+     }
+ }
+ 
+ /**
+  * Special type of trace that can be used for catching of
+  * output of other traces.
+  *
+  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+  * @package moodlecore
+  */
+ class progress_trace_buffer extends progress_trace {
+     /** @var progres_trace */
+     protected $trace;
+     /** @var bool do we pass output out */
+     protected $passthrough;
+     /** @var string output buffer */
+     protected $buffer;
+ 
+     /**
+      * Constructor.
+      *
+      * @param progress_trace $trace
+      * @param bool $passthrough true means output and buffer, false means just buffer and no output
+      */
+     public function __construct(progress_trace $trace, $passthrough = true) {
+         $this->trace       = $trace;
+         $this->passthrough = $passthrough;
+         $this->buffer      = '';
+     }
+ 
+     /**
+      * Output the trace message.
+      *
+      * @param string $message the message to output.
+      * @param int $depth indent depth for this message.
+      * @return void output stored in buffer
+      */
+     public function output($message, $depth = 0) {
+         ob_start();
+         $this->trace->output($message, $depth);
+         $this->buffer .= ob_get_contents();
+         if ($this->passthrough) {
+             ob_end_flush();
+         } else {
+             ob_end_clean();
+         }
+     }
+ 
+     /**
+      * Called when the processing is finished.
+      */
+     public function finished() {
+         ob_start();
+         $this->trace->finished();
+         $this->buffer .= ob_get_contents();
+         if ($this->passthrough) {
+             ob_end_flush();
+         } else {
+             ob_end_clean();
+         }
+     }
+ 
+     /**
+      * Reset internal text buffer.
+      */
+     public function reset_buffer() {
+         $this->buffer = '';
+     }
+ 
+     /**
+      * Return internal text buffer.
+      * @return string buffered plain text
+      */
+     public function get_buffer() {
+         return $this->buffer;
+     }
+ }
+ 
+ /**
+  * Special type of trace that can be used for redirecting to multiple
+  * other traces.
+  *
+  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+  * @package moodlecore
+  */
+ class combined_progress_trace extends progress_trace {
+     protected $traces;
+ 
+     /**
+      * @param array $traces multiple traces
+      */
+     public function __construct(array $traces) {
+         $this->traces = $traces;
+     }
+ 
+     /**
+      * Output an progress message in whatever format.
+      *
+      * @param string $message the message to output.
+      * @param integer $depth indent depth for this message.
+      */
+     public function output($message, $depth = 0) {
+         foreach($this->traces as $trace) {
+             $trace->output($message, $depth);
+         }
+     }
+ 
+     /**
+      * Called when the processing is finished.
+      */
+     public function finished() {
+         foreach($this->traces as $trace) {
+             $trace->finished();
+         }
+     }
+ }
+ 
  /**
   * Returns a localized sentence in the current language summarizing the current password policy
   *