<?php

/**

 * @file

 * System monitoring and logging for administrators.

 *

 * The Database Logging module monitors your site and keeps a list of recorded

 * events containing usage and performance data, errors, warnings, and similar

 * operational information.

 *

 * @see watchdog()

 */

/**

 * Implements hook_help().

 */

function dblog_help($path, $arg) {

  switch ($path) {

    case 'admin/help#dblog':

      $output = '';

      $output .= '<h3>' . t('About') . '</h3>';

      $output .= '<p>' . t('The Database logging module logs system events in the Drupal database. For more information, see the online handbook entry for the <a href="@dblog">Database logging module</a>.', array('@dblog' => 'http://drupal.org/documentation/modules/dblog')) . '</p>';

      $output .= '<h3>' . t('Uses') . '</h3>';

      $output .= '<dl>';

      $output .= '<dt>' . t('Monitoring your site') . '</dt>';

      $output .= '<dd>' . t('The Database logging module allows you to view an event log on the <a href="@dblog">Recent log messages</a> page. The log is a chronological list of recorded events containing usage data, performance data, errors, warnings and operational information. Administrators should check the log on a regular basis to ensure their site is working properly.', array('@dblog' => url('admin/reports/dblog'))) . '</dd>';

      $output .= '<dt>' . t('Debugging site problems') . '</dt>';

      $output .= '<dd>' . t('In case of errors or problems with the site, the <a href="@dblog">Recent log messages</a> page can be useful for debugging, since it shows the sequence of events. The log messages include usage information, warnings, and errors.', array('@dblog' => url('admin/reports/dblog'))) . '</dd>';

      $output .= '</dl>';

      return $output;

    case 'admin/reports/dblog':

      return '<p>' . t('The Database logging module monitors your website, capturing system events in a log (shown here) to be reviewed by an authorized individual at a later time. This log is a list of recorded events containing usage data, performance data, errors, warnings and operational information. It is vital to check the Recent log messages report on a regular basis, as it is often the only way to tell what is going on.') . '</p>';

  }

}

/**

 * Implements hook_menu().

 */

function dblog_menu() {

  $items['admin/reports/dblog'] = array(

    'title' => 'Recent log messages',

    'description' => 'View events that have recently been logged.',

    'page callback' => 'dblog_overview',

    'access arguments' => array('access site reports'),

    'weight' => -1,

    'file' => 'dblog.admin.inc',

  );

  $items['admin/reports/page-not-found'] = array(

    'title' => "Top 'page not found' errors",

    'description' => "View 'page not found' errors (404s).",

    'page callback' => 'dblog_top',

    'page arguments' => array('page not found'),

    'access arguments' => array('access site reports'),

    'file' => 'dblog.admin.inc',

  );

  $items['admin/reports/access-denied'] = array(

    'title' => "Top 'access denied' errors",

    'description' => "View 'access denied' errors (403s).",

    'page callback' => 'dblog_top',

    'page arguments' => array('access denied'),

    'access arguments' => array('access site reports'),

    'file' => 'dblog.admin.inc',

  );

  $items['admin/reports/event/%'] = array(

    'title' => 'Details',

    'page callback' => 'dblog_event',

    'page arguments' => array(3),

    'access arguments' => array('access site reports'),

    'file' => 'dblog.admin.inc',

  );

  if (module_exists('search')) {

    $items['admin/reports/search'] = array(

      'title' => 'Top search phrases',

      'description' => 'View most popular search phrases.',

      'page callback' => 'dblog_top',

      'page arguments' => array('search'),

      'access arguments' => array('access site reports'),

      'file' => 'dblog.admin.inc',

    );

  }

  return $items;

}

/**

 * Implements hook_init().

 */

function dblog_init() {

  if (arg(0) == 'admin' && arg(1) == 'reports') {

    // Add the CSS for this module

    drupal_add_css(drupal_get_path('module', 'dblog') . '/dblog.css');

  }

}

/**

 * Implements hook_cron().

 *

 * Controls the size of the log table, paring it to 'dblog_row_limit' messages.

 */

function dblog_cron() {

  // Cleanup the watchdog table.

  $row_limit = variable_get('dblog_row_limit', 1000);

  // For row limit n, get the wid of the nth row in descending wid order.

  // Counting the most recent n rows avoids issues with wid number sequences,

  // e.g. auto_increment value > 1 or rows deleted directly from the table.

  if ($row_limit > 0) {

    $min_row = db_select('watchdog', 'w')

      ->fields('w', array('wid'))

      ->orderBy('wid', 'DESC')

      ->range($row_limit - 1, 1)

      ->execute()->fetchField();

    // Delete all table entries older than the nth row, if nth row was found.

    if ($min_row) {

      db_delete('watchdog')

        ->condition('wid', $min_row, '<')

        ->execute();

    }

  }

}

/**

 * Gathers a list of uniquely defined database log message types.

 *

 * @return array

 *   List of uniquely defined database log message types.

 */

function _dblog_get_message_types() {

  $types = array();

  $result = db_query('SELECT DISTINCT(type) FROM {watchdog} ORDER BY type');

  foreach ($result as $object) {

    $types[] = $object->type;

  }

  return $types;

}

/**

 * Implements hook_watchdog().

 *

 * Note: Some values may be truncated to meet database column size restrictions.

 */

function dblog_watchdog(array $log_entry) {

  if (!function_exists('drupal_substr')) {

    require_once DRUPAL_ROOT . '/includes/unicode.inc';

  }

  try {

    Database::getConnection('default', 'default')->insert('watchdog')

      ->fields(array(

        'uid' => $log_entry['uid'],

        'type' => drupal_substr($log_entry['type'], 0, 64),

        'message' => $log_entry['message'],

        'variables' => serialize($log_entry['variables']),

        'severity' => $log_entry['severity'],

        'link' => drupal_substr($log_entry['link'], 0, 255),

        'location' => $log_entry['request_uri'],

        'referer' => $log_entry['referer'],

        'hostname' => drupal_substr($log_entry['ip'], 0, 128),

        'timestamp' => $log_entry['timestamp'],

      ))

      ->execute();

  }

  catch (Exception $e) {

    // Exception is ignored so that watchdog does not break pages during the

    // installation process or is not able to create the watchdog table during

    // installation.

  }

}

/**

 * Implements hook_form_FORM_ID_alter() for system_logging_settings().

 */

function dblog_form_system_logging_settings_alter(&$form, $form_state) {

  $form['dblog_row_limit'] = array(

    '#type' => 'select',

    '#title' => t('Database log messages to keep'),

    '#default_value' => variable_get('dblog_row_limit', 1000),

    '#options' => array(0 => t('All')) + drupal_map_assoc(array(100, 1000, 10000, 100000, 1000000)),

    '#description' => t('The maximum number of messages to keep in the database log. Requires a <a href="@cron">cron maintenance task</a>.', array('@cron' => url('admin/reports/status')))

  );

  $form['actions']['#weight'] = 1;

}

/**

 * Implements hook_theme().

 */

function dblog_theme() {

  return array(

    'dblog_message' => array(

      'variables' => array('event' => NULL, 'link' => FALSE),

      'file' => 'dblog.admin.inc',

    ),

  );

}