<?php
// $Id$
/**
 * @file
 * APC instrumentation for Munin
 *
 * @author Frederic G. MARAND
 *
 * @copyright (c) 2011 Ouest Systèmes Informatiques
 *
 * Licensed under the General Public License version 2 or later.
 */

/**
 * Implements hook_munin_api_info().
 *
 * @return
 *   An array of Munin probes informations, index by probe name.
 */
function munin_apc_munin_api_info() {
  $int = array(
    '#graph_printf' => '%d',
  );

  $ret = array(
    'munin_apc' => array(
      '#title' => t('PHP APC'),
      '#info' => t('Collect cache information for the Alternative PHP Cache'),
      'total_size' => $int + array(
        '#label'     => t('Bytes allocated'),
        '#type'      => MUNIN_API_GAUGE,
        '#info'      => t('Number of bytes allocated to APC.')
      ),
      'used_size'  => $int + array(
        '#label'     => t('Bytes in use'),
        '#type'      => MUNIN_API_GAUGE,
        '#info'      => t('Number of bytes actually used by APC, either cached or deleted'),
      ),
      'uptime'     => $int + array(
        '#label'     => t('Up-time of APC instance'),
        '#type'      => MUNIN_API_GAUGE,
        '#info'      => t('Seconds since last APC restart.'),
      ),
      'num_hits'   => $int + array(
        '#label'     => t('Hits since last restart'),
        '#type'      => MUNIN_API_COUNTER,
      ),
      'num_misses' => $int + array(
        '#label'     => t('Misses since last restart'),
        '#type'      => MUNIN_API_COUNTER,
      ),
      'num_inserts' => $int + array(
        '#label'     => t('Insertions since last restart'),
        '#type'      => MUNIN_API_COUNTER,
      ),
//      'hit_rate'   => $int + array(
//        '#label'     => t('Hit/miss ratio since last restart'),
//        '#type'      => MUNIN_API_GAUGE,
//      ),
      'cache_entries' => $int + array(
        '#label'     => t('Number of cache entries'),
        '#type'      => MUNIN_API_GAUGE,
      ),
      'deleted_entries' => $int + array(
        '#label'     => t('Number of deleted entries'),
        '#type'      => MUNIN_API_GAUGE,
        '#info'      => t('Deleted entries lingering until the garbage collection TTL elapses'),
      ),
    ),
  );

  return $ret;
}

/**
 * Implements hook_munin_api_fetch().
 */
function munin_apc_munin_api_fetch() {
  $info = apc_sma_info();
  $ret = array();

  // SMA Info
  $total = $info['num_seg'] * $info['seg_size'];
  $ret['total_size'] = (int) $total;
  $ret['used_size'] = (int) ($total - $info['avail_mem']);

  // Cache info
  $info = apc_cache_info();
  $ret['uptime']      = time() - $info['start_time'];
  foreach (array('num_hits', 'num_misses', 'num_inserts') as $field) {
    $ret[$field] = $info[$field];
  }

  $ret['cache_entries']   = count($info['cache_list']);
  $ret['deleted_entries'] = count($info['deleted_list']);

  return $ret;
}