user.module

<?php
// $Id$

/**
 * @file
 * Enables the user registration and login system.
 */

/**
 * Invokes hook_user() in every module.
 *
 * We cannot use module_invoke() for this, becuse the arguments need to
 * be passed by reference.
 */
function user_module_invoke($type, &$array, &$user, $category = NULL) {
  foreach (module_list() as $module) {
    $function = $module .'_user';
    if (function_exists($function)) $function($type, $array, $user, $category);
  }
}

function user_external_load($authname) {
  $result = db_query("SELECT uid FROM {authmap} WHERE authname = '%s'", $authname);

  if ($user = db_fetch_object($result)) {
    return user_load($user);
  }
  else {
    return 0;
  }
}

/**
 * Fetch a user object.
 *
 * @param $array
 *   An associative array of attributes to search for in selecting the
 *   user, such as user name or email address.
 *
 * @return
 *   A fully-loaded $user object.
 */
function user_load($array = array()) {
  // Dynamically compose a SQL query:
  $query = '';

  foreach ($array as $key => $value) {
    if ($key == 'pass') {
      $query .= "u.$key = '". md5($value) ."' AND ";
    }
    else {
      $query .= "LOWER(u.$key) = '". strtolower(check_query($value)) ."' AND ";
    }
  }
  $result = db_query_range("SELECT u.* FROM {users} u WHERE $query u.status < 3", 0, 1);

  $user = db_fetch_object($result);
  $user = drupal_unpack($user);
  user_module_invoke('load', $array, $user);

  $user->roles = array();
  $result = db_query('SELECT r.rid, r.name FROM {role} r INNER JOIN {users_roles} ur ON ur.rid = r.rid WHERE ur.uid = %d', $user->uid);
  while ($role = db_fetch_object($result)) {
    $user->roles[$role->rid] = $role->name;
  }

  return $user;
}

function user_save($account, $array = array(), $category = 'account') {
  // Dynamically compose a SQL query:
  $user_fields = user_fields();
  if ($account->uid) {
    user_module_invoke('update', $array, $account, $category);

    $data = unserialize(db_result(db_query('SELECT data FROM {users} WHERE uid = %d', $account->uid)));
    foreach ($array as $key => $value) {
      if ($key == 'pass') {
        $query .= "$key = '%s', ";
        $v[] = md5($value);
      }
      else if (substr($key, 0, 4) !== 'auth') {
        if (in_array($key, $user_fields)) {
          // escape '%'s:
          $value = str_replace('%', '%%', $value);
          $query .= "$key = '%s', ";
          $v[] = $value;
        }
        else {
          $data[$key] = $value;
        }
      }
    }
    $query .= "data = '%s', ";
    $v[] = serialize($data);

    db_query("UPDATE {users} SET $query changed = %d WHERE uid = %d", array_merge($v, array(time(), $account->uid)));

    // reload user roles if provided
    if (is_array($array['roles'])) {
      db_query('DELETE FROM {users_roles} WHERE uid = %d', $account->uid);

      foreach ($array['roles'] as $rid) {
        db_query('INSERT INTO {users_roles} (uid, rid) VALUES (%d, %d)', $account->uid, $rid);
      }
    }

    $user = user_load(array('uid' => $account->uid));
  }
  else {
    $array['created'] = time();
    $array['changed'] = time();
    $array['uid'] = db_next_id('{users}_uid');

    foreach ($array as $key => $value) {
      if ($key == 'pass') {
        $fields[] = check_query($key);
        $values[] = md5($value);
        $s[] = "'%s'";
      }
      else if (substr($key, 0, 4) !== 'auth') {
        if (in_array($key, $user_fields)) {
          $fields[] = check_query($key);
          $values[] = $value;
          $s[] = "'%s'";
        }
        else {
          $data[$key] = $value;
        }
      }
    }

    $fields[] = 'data';
    $values[] = serialize($data);
    $s[] = "'%s'";

    db_query('INSERT INTO {users} ('. implode(', ', $fields) .') VALUES ('. implode(', ', $s) .')', $values);

    // Reload user roles (delete just to be safe).
    db_query('DELETE FROM {users_roles} WHERE uid = %d', $array['uid']);

    foreach ($array['roles'] as $rid) {
      db_query('INSERT INTO {users_roles} (uid, rid) VALUES (%d, %d)', $array['uid'], $rid);
    }

    $user = user_load(array('name' => $array['name']));

    module_invoke_all('user', 'insert', $array, $user, $category);
  }

  foreach ($array as $key => $value) {
    if (substr($key, 0, 4) == 'auth') {
      $authmaps[$key] = $value;
    }
  }

  if ($authmaps) {
    user_set_authmaps($user, $authmaps);
  }

  return $user;
}

/**
 * Verify the syntax of the given name.
 */
function user_validate_name($name) {
  if (!$name) return t('You must enter a username.');
  if (substr($name, 0, 1) == ' ') return t('The username cannot begin with a space.');
  if (substr($name, -1) == ' ') return t('The username cannot end with a space.');
  if (ereg('  ', $name)) return t('The username cannot contain multiple spaces in a row.');
  if (ereg('[^ [:alnum:]@_.-]', $name)) return t('The username contains an illegal character.');
  if (ereg('@', $name) && !eregi('@([0-9a-z](-?[0-9a-z])*.)+[a-z]{2}([zmuvtg]|fo|me)?$', $name)) return t('The username is not a valid authentication ID.');
  if (strlen($name) > 56) return t('The username "%name" is too long: it must be less than 56 characters.', array('%name' => $name));
}

function user_validate_mail($mail) {
  if (!$mail) return t('You must enter an e-mail address.');
  if (!valid_email_address($mail)) {
    return t('The e-mail address "%mail" is not valid.', array('%mail' => $mail));
  }
}

function user_validate_picture($file, &$edit, $user) {
  // Initialize the picture:
  $edit['picture'] = $user->picture;

  // Check that uploaded file is an image, with a maximum file size
  // and maximum height/width.
  $extension = strtolower(strrchr($file->filename, '.'));
  $size = @getimagesize($file->filepath);
  list($maxwidth, $maxheight) = explode('x', variable_get('user_picture_dimensions', '85x85'));

  if ((!in_array($size[2], array(1, 2, 3))) || (!in_array($extension, array('.gif', '.jpg', '.png', '.jpeg')))) {
    form_set_error('picture', t('The uploaded file was not an image.'));
  }
  else if ($file->size > (variable_get('user_picture_file_size', '30') * 1000)) {
    form_set_error('picture', t('The uploaded image is too large; the maximum file size is %size kB.', array('%size' => variable_get('user_picture_file_size', '30'))));
  }
  else if ($size[0] > $maxwidth || $size[1] > $maxheight) {
    form_set_error('picture', t('The uploaded image is too large; the maximum dimensions are %dimensions pixels.', array('%dimensions' => variable_get('user_picture_dimensions', '85x85'))));
  }
  else if ($file = file_save_upload('picture', variable_get('user_picture_path', 'pictures') . FILE_SEPARATOR .'picture-'. $user->uid . $extension, 1)) {
    $edit['picture'] = $file->filepath;
  }
  else {
    form_set_error('picture', t("Failed to upload the picture image; the %directory directory doesn't exist.", array('%directory' => '<em>'. variable_get('user_picture_path', 'pictures') .'</em>')));
  }
}

function user_validate_authmap($account, $authname, $module) {
  $result = db_query("SELECT COUNT(*) from {authmap} WHERE uid != %d AND authname = '%s'", $account->uid, $authname);
  if (db_result($result) > 0) {
    $name = module_invoke($module, 'info', 'name');
    return t('The %u ID %s is already taken.', array('%u' => $name, '%s' => "<em>$authname</em>"));
  }
}

/**
 * Generate a random alphanumeric password.
 */
function user_password($length = 10) {
  // This variable contains the list of allowable characters for the
  // password.  Note that the number 0 and the letter 'O' have been
  // removed to avoid confusion between the two.  The same is true
  // of 'I' and 1.
  $allowable_characters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789';

  // We see how many characters are in the allowable list:
  $len = strlen($allowable_characters);

  // Seed the random number generator with the microtime stamp.
  mt_srand((double)microtime() * 1000000);

  // Declare the password as a blank string.
  $pass = '';

  // Loop the number of times specified by $length.
  for ($i = 0; $i < $length; $i++) {

    // Each iteration, pick a random character from the
    // allowable string and append it to the password:
    $pass .= $allowable_characters[mt_rand(0, $len - 1)];
  }

  return $pass;
}

/**
 * Determine whether the user has a given privilege.
 *
 * @param $string
 *   The permission, such as "administer nodes", being checked for.
 *
 * @return
 *   TRUE iff the current user has the requested permission.
 *
 * All permission checks in Drupal should go through this function. This
 * way, we guarantee consistent behavior, and ensure that the superuser
 * can perform all actions.
 */
function user_access($string) {
  global $user;
  static $perm = 0;

  // User #1 has all priveleges:
  if ($user->uid == 1) {
    return 1;
  }

  // To reduce the number of SQL queries, we cache the user's permissions
  // in a static variable.
  if ($perm === 0) {
    $result = db_query('SELECT DISTINCT(p.perm) FROM {role} r INNER JOIN {permission} p ON p.rid = r.rid INNER JOIN {users_roles} ur ON ur.rid = r.rid WHERE ur.uid = %d', $user->uid);

    while ($row = db_fetch_object($result)) {
      $perm .= "$row->perm, ";
    }
  }

  return strstr($perm, "$string, ");
}

/**
 * Send an e-mail message.
 */
function user_mail($mail, $subject, $message, $header) {
  if (variable_get('smtp_library', '') && file_exists(variable_get('smtp_library', ''))) {
    include_once variable_get('smtp_library', '');
    return user_mail_wrapper($mail, $subject, $message, $header);
  }
  else {
    /*
    ** Note: if you are having problems with sending mail, or mails look wrong
    ** when they are recieved you may have to modify the str_replace to suit
    ** your systems.
    **  - \r\n will work under dos and windows.
    **  - \n will work for linux, unix and BSDs.
    **  - \r will work for macs.
    **
    ** According to RFC 2646, it's quite rude to not wrap your e-mails:
    **
    ** "The Text/Plain media type is the lowest common denominator of
    ** Internet email, with lines of no more than 997 characters (by
    ** convention usually no more than 80), and where the CRLF sequence
    ** represents a line break [MIME-IMT]."
    **
    ** CRLF === \r\n
    **
    ** http://www.rfc-editor.org/rfc/rfc2646.txt
    **
    */
    return mail(
      $mail,
      mime_header_encode($subject),
      str_replace("\r", '', $message),
      "MIME-Version: 1.0\nContent-Type: text/plain; charset=UTF-8; format=flowed\nContent-transfer-encoding: 8Bit\n" . $header
    );
  }
}

function user_deny($type, $mask) {
  $allow = db_fetch_object(db_query("SELECT * FROM {access} WHERE status = 1 AND type = '%s' AND LOWER('%s') LIKE LOWER(mask)", $type, $mask));
  $deny = db_fetch_object(db_query("SELECT * FROM {access} WHERE status = 0 AND type = '%s' AND LOWER('%s') LIKE LOWER(mask)", $type, $mask));

  return $deny && !$allow;
}

function user_fields() {
  static $fields;

  if (!$fields) {
    $result = db_query('SELECT * FROM {users} WHERE uid = 1');
    if (db_num_rows($result)) {
      $fields = array_keys(db_fetch_array($result));
    }
    else {
      // Make sure we return the default fields at least
      $fields = array('uid', 'name', 'pass', 'mail', 'picture', 'mode', 'sort', 'threshold', 'theme', 'signature', 'created', 'changed', 'status', 'timezone', 'language', 'init', 'data');
    }
  }

  return $fields;
}

/**
 * Implementation of hook_perm().
 */
function user_perm() {
  return array('administer users');
}

/**
 * Implementation of hook_file_download().
 *
 * Ensure that user pictures (avatars) are always downloadable.
 */
function user_file_download($file) {
  if (strpos($file, variable_get('user_picture_path', 'pictures') . FILE_SEPARATOR . 'picture-') === 0) {
    list($width, $height, $type, $attr) = @getimagesize(file_create_path($file));
    $types = array(
      IMAGETYPE_GIF => 'image/gif',
      IMAGETYPE_JPEG => 'image/jpeg',
      IMAGETYPE_PNG => 'image/png',
      IMAGETYPE_SWF => 'application/x-shockwave-flash',
      IMAGETYPE_PSD => 'image/psd',
      IMAGETYPE_BMP => 'image/bmp',
      IMAGETYPE_TIFF_II => 'image/tiff',
      IMAGETYPE_TIFF_MM  => 'image/tiff',
      IMAGETYPE_JPC => 'application/octet-stream',
      IMAGETYPE_JP2 => 'image/jp2',
      IMAGETYPE_JPX => 'application/octet-stream',
      IMAGETYPE_JB2 => 'application/octet-stream',
      IMAGETYPE_SWC => 'application/x-shockwave-flash',
      IMAGETYPE_IFF => 'image/iff',
      IMAGETYPE_WBMP => 'image/vnd.wap.wbmp',
      IMAGETYPE_XBM => 'image/xbm'
    );
    return array('Content-type: '. $types[$type]);
  }
}

/**
 * Implementation of hook_search().
 */
function user_search($keys) {
  $find = array();

  // Replace wildcards with MySQL/PostgreSQL wildcards.
  $keys = str_replace('*', '%', $keys);

  $result = db_query_range("SELECT * FROM {users} WHERE LOWER(name) LIKE '%%%s%%'", strtolower($keys), 0, 20);
  while ($account = db_fetch_object($result)) {
    $find[] = array('title' => $account->name, 'link' => url("user/$account->uid/view"), 'user' => $account->name);
  }
  return array(t('Matching users'), $find);
}

/**
 * Implementation of hook_user().
 */
function user_user($type, &$edit, &$user, $category = NULL) {
  if ($type == 'view') {
    return array(t('History') => form_item(t('Member for'), format_interval(time() - $user->created)));
  }

  if ($type == 'form' && $category == 'account') {
    return user_edit_form(arg(1), $edit);
  }

  if ($type == 'validate' && $category == 'account') {
    return user_edit_validate(arg(1), $edit);
  }

  if ($type == 'categories') {
    return array(array('name' => 'account', 'title' => t('account settings'), 'weight' => 1));
  }
}

/**
 * Implementation of hook_block().
 */
function user_block($op = 'list', $delta = 0) {
  global $user;

  if ($op == 'list') {
     $blocks[0]['info'] = t('User login');
     $blocks[1]['info'] = t('Navigation');
     $blocks[2]['info'] = t('Who\'s new');
     $blocks[3]['info'] = t('Who\'s online');

     return $blocks;
  }
  else {
    $block = array();

    switch ($delta) {
      case 0:

        if (!$user->uid) {
          // For usability's sake, avoid showing two login forms on one page.
          if (arg(0) == 'user' && arg(1) != 'view') {
            return;
          }

          $edit = $_POST['edit'];

          $output = "<div class=\"user-login-block\">\n";

          // Save the referer.  We record where the user came from such
          // that we can redirect him after having completed the login form.

          if (empty($edit)) {
            $edit['destination'] = $_GET['q'];
          }
          // NOTE: special care needs to be taken because on pages with forms,
          // such as node and comment submission pages, the $edit variable
          // might already be set.

          $output .= form_hidden('destination', $edit['destination']);
          $output .= form_textfield(t('Username'), 'name', $edit['name'], 15, 64);
          $output .= form_password(t('Password'), 'pass', $pass, 15, 64);
          $output .= form_submit(t('Log in'));
          $output .= "</div>\n";

          $output  = form($output, 'post', url('user/login'));

          if (variable_get('user_register', 1)) {
            $items[] = l(t('Create new account'), 'user/register', array('title' => t('Create a new user account.')));
          }
          $items[] = l(t('Request new password'), 'user/password', array('title' => t('Request new password via e-mail.')));

          $output .= theme('item_list', $items);

          $block['subject'] = t('User login');
          $block['content'] = $output;
        }
        return $block;
      case 1:
        if ($menu = theme('menu_tree')) {
           $block['subject'] = $user->uid ? $user->name : t('Navigation');
           $block['content'] = '<div class="menu">'. $menu .'</div>';
        }
        return $block;
      case 2:
        if (user_access('access content')) {
          $result = db_query_range('SELECT uid, name FROM {users} WHERE status != 0 ORDER BY uid DESC', 0, 5);
          while ($account = db_fetch_object($result)) {
            $items[] = format_name($account);
          }

          $output = theme('user_list', $items);

          $block['subject'] = t('Who\'s new');
          $block['content'] = $output;
          return $block;
        }
      case 3:
        if (user_access('access content')) {
          // Count users with activity in the past defined period.
          $time_period = variable_get('user_block_seconds_online', 2700);

          // Perform database queries to gather online user lists.
          $guests = db_fetch_object(db_query('SELECT COUNT(DISTINCT(sid)) AS count FROM {sessions} WHERE timestamp >= %d AND uid = 0', time() - $time_period));
          $users = db_query('SELECT DISTINCT(uid), MAX(timestamp) AS max_timestamp FROM {sessions} WHERE timestamp >= %d AND uid != 0 GROUP BY uid ORDER BY max_timestamp DESC', time() - $time_period );
          $total_users = db_num_rows($users);

          // Perform database queries to count all users
          $all_users = db_fetch_object(db_query('SELECT COUNT(uid) AS count FROM {users} WHERE uid != 0 AND status != 0'));

          // Format the output with proper grammar.
          if ($total_users == 1 && $guests->count == 1) {
            $output = t('There is currently %members and %visitors online.', array('%members' => format_plural($total_users, '1 user', '%count users'), '%visitors' => format_plural($guests->count, '1 guest', '%count guests')));
          }
          else {
            $output = t('There are currently %members and %visitors online.', array('%members' => format_plural($total_users, '1 user', '%count users'), '%visitors' => format_plural($guests->count, '1 guest', '%count guests')));
          }

          // Display a list of currently online users.
          $max_users = variable_get('user_block_max_list_count', 10);
          if ($max_users) {
            $items = array();

            while ($max_users-- && $uid = db_fetch_object($users)) {
              $items[] = format_name(user_load(array('uid' => $uid->uid)));
            }

            if ($items) {
              if (db_fetch_object($users)) {
                $items[] = '...';
              }
              $output .= theme('item_list', $items, t('Online users:'));
            }
          }

          $block['subject'] = t('Who\'s online');
          $block['content'] = $output;
        }
        return $block;
    }
  }
}

function theme_user_picture($account) {
  if (variable_get('user_pictures', 0)) {
    if ($account->picture && file_exists($account->picture)) {
      $picture = file_create_url($account->picture);
    }
    else if (variable_get('user_picture_default', '')) {
      $picture = variable_get('user_picture_default', '');
    }

    if ($picture) {
      $alt = t('%user\'s picture', array('%user' => $account->name ? $account->name : t(variable_get('anonymous', 'Anonymous'))));
      $picture = theme('image', $picture, $alt, $alt, '', false);
      if ($account->uid) {
        $picture = l($picture, "user/$account->uid", array('title' => t('View user profile.')));
      }

      return "<div class=\"picture\">$picture</div>";
    }
  }
}

function theme_user_profile($account, $fields) {
  $output = "<div class=\"profile\">\n";
  $output .= theme('user_picture', $account);
  foreach ($fields as $category => $value) {
    $output .= "<h2>$category</h2>$value";
  }
  $output .= "</div>\n";

  return $output;
}

function theme_user_list($items, $title = NULL) {
  return theme('item_list', $items, $title);
}

/**
 * Implementation of hook_menu().
 */
function user_menu() {
  global $user;

  $items = array();

  $access = user_access('administer users');

  if (arg(0) == 'user' && is_numeric(arg(1))) {
    $items[] = array('path' => 'user/'. arg(1), 'title' => t('user'),
      'type' => MENU_CALLBACK, 'callback' => 'user_page', 'access' => TRUE);
    $items[] = array('path' => 'user/'. arg(1) .'/view', 'title' => t('view'),
      'type' => MENU_DEFAULT_LOCAL_TASK, 'weight' => -10);
    $items[] = array('path' => 'user/'. arg(1) .'/edit', 'title' => t('edit'),
      'callback' => 'user_edit', 'access' => $access || $user->uid == arg(1),
      'type' => MENU_LOCAL_TASK);

    if (arg(2) == 'edit') {
      if (($categories = _user_categories()) && (count($categories) > 1)) {
        foreach ($categories as $key => $category) {
          $items[] = array('path' => 'user/'. arg(1) .'/edit/'. $category['name'], 'title' => $category['title'],
            'type' => $category['name'] == 'account' ? MENU_DEFAULT_LOCAL_TASK : MENU_LOCAL_TASK,
            'weight' => $category['weight']);
        }
      }
    }
  }

  if ($user->uid) {
    $items[] = array('path' => "user/$user->uid", 'title' => t('my account'),
      'callback' => 'user_page', 'access' => TRUE);
    $items[] = array('path' => 'logout', 'title' => t('log out'),
      'access' => TRUE,
      'callback' => 'user_logout',
      'weight' => 10);
  }
  else {
    $items[] = array('path' => 'logout', 'title' => t('log out'),
      'callback' => 'user_logout', 'access' => FALSE);
  }

  $items[] = array('path' => 'user', 'title' => t('user'),
    'callback' => 'user_page', 'access' => TRUE,
    'type' => MENU_CALLBACK);
  $items[] = array('path' => 'user/login', 'title' => t('log in'),
    'callback' => 'user_page', 'access' => TRUE, 'type' => MENU_CALLBACK);
  $items[] = array('path' => 'user/register', 'title' => t('register'),
    'callback' => 'user_page', 'access' => TRUE, 'type' => MENU_CALLBACK);
  $items[] = array('path' => 'user/password', 'title' => t('request new password'),
    'callback' => 'user_page', 'access' => TRUE, 'type' => MENU_CALLBACK);

  $items[] = array('path' => 'admin/user', 'title' => t('users'),
    'callback' => 'user_admin', 'access' => $access);
  $items[] = array('path' => 'admin/user/list', 'title' => t('list'),
    'type' => MENU_DEFAULT_LOCAL_TASK, 'weight' => -10);
  $items[] = array('path' => 'admin/user/create', 'title' => t('add'),
    'callback' => 'user_admin', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure', 'title' => t('configure'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure/settings', 'title' => t('settings'),
    'type' => MENU_DEFAULT_LOCAL_TASK, 'weight' => -10);
  $items[] = array('path' => 'admin/user/configure/access', 'title' => t('access rules'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure/access/mail', 'title' => t('e-mail rules'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure/access/user', 'title' => t('name rules'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure/role', 'title' => t('roles'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);
  $items[] = array('path' => 'admin/user/configure/permission', 'title' => t('permissions'),
    'callback' => 'user_configure', 'access' => $access,
    'type' => MENU_LOCAL_TASK);

  if (module_exist('search')) {
    $items[] = array('path' => 'admin/user/search', 'title' => t('search'),
      'callback' => 'user_admin', 'access' => $access,
      'type' => MENU_LOCAL_TASK);
  }

  return $items;
}

/**
 * Called by authentication modules in order to edit/view their authmap information.
 */
function user_get_authname($account, $module) {
  $result = db_query("SELECT authname FROM {authmap} WHERE uid = %d AND module = '%s'", $account->uid, $module);
  return db_result($result);
}

/**
 * Accepts an user object, $account, or a DA name and returns an associative
 * array of modules and DA names. Called at external login.
 */
function user_get_authmaps($authname = NULL) {
  $result = db_query("SELECT authname, module FROM {authmap} WHERE authname = '%s'", $authname);
  if (db_num_rows($result) > 0) {
    while ($authmap = db_fetch_object($result)) {
      $authmaps[$authmap->module] = $authmap->authname;
    }
    return $authmaps;
  }
  else {
    return 0;
  }
}

function user_set_authmaps($account, $authmaps) {
  foreach ($authmaps as $key => $value) {
    $module = explode('_', $key, 2);
    if ($value) {
      db_query("UPDATE {authmap} SET authname = '%s' WHERE uid = %d AND module = '%s'", $value, $account->uid, $module['1']);
      if (!db_affected_rows()) {
        db_query("INSERT INTO {authmap} (authname, uid, module) VALUES ('%s', %d, '%s')", $value, $account->uid, $module[1]);
      }
    }
    else {
      db_query("DELETE FROM {authmap} WHERE uid = %d AND module = '%s'", $account->uid, $module['1']);
    }
  }
}

function user_auth_help_links() {
  $links = array();
  foreach (module_list() as $module) {
    if (module_hook($module, 'auth')) {
      $links[] = l(module_invoke($module, 'info', 'name'), "user/help#$module");
    }
  }
  return $links;
}

/*** User features *********************************************************/

function user_login($edit = array(), $msg = '') {
  global $user, $base_url;

  // If we are already logged on, go to the user page instead.
  if ($user->uid) {
    drupal_goto('user');
  }

  if (user_deny('user', $edit['name'])) {
    $error = t('The name %s has been denied access.', array('%s' => '<em>'. $edit['name'] .'</em>'));
  }
  else if ($edit['name'] && $edit['pass']) {

    if (!$user->uid) {
      $user = user_authenticate($edit['name'], $edit['pass']);
    }

    if ($user->uid) {
      watchdog('user', t('Session opened for %name.', array('%name' => "<em>$user->name</em>")));

      // Update the user table timestamp noting user has logged in.
      db_query("UPDATE {users} SET changed = '%d' WHERE uid = '%s'", time(), $user->uid);

      user_module_invoke('login', $edit, $user);

      // If the user wants to be remembered, set the proper cookie such
      // that the session won't expire.
      $path = preg_replace("/.+\/\/[^\/]+(.*)/", "\$1/", $base_url);
      setcookie(session_name(), session_id(), FALSE, $path);

      // Redirect the user to the page he logged on from.
      drupal_goto($edit['destination']);
    }
    else {
      if (!$error) {
        $error = t('Sorry.  Unrecognized username or password.') .' '. l(t('Have you forgotten your password?'), 'user/password');
      }
      watchdog('user', t('Login attempt failed for %user: %error.', array('%user' => '<em>'. $server ? ($name .'@'. $server) : $name .'</em>', '%error' => "<em>$error</em>")));
    }
  }

  // Display error message (if any):
  if ($error) {
    drupal_set_message($error, 'error');
  }

  // Save the referrer.  We record where the user came from such that we
  // can redirect him after having completed the login form.
  if (empty($edit)) {
    $edit['destination'] = $_GET['q'];
  }
  $output .= form_hidden('destination', $edit['destination']);

  // Display login form:
  if ($msg) {
    $output .= "<p>$msg</p>";
  }
  if (count(user_auth_help_links()) > 0) {
    $output .= form_textfield(t('Username'), 'name', $edit['name'], 30, 64, t('Enter your %s username, or an ID from one of our affiliates: %a.', array('%s' => variable_get('site_name', 'local'), '%a' => implode(', ', user_auth_help_links()))));
  }
  else {
    $output .= form_textfield(t('Username'), 'name', $edit['name'], 30, 64, t('Enter your %s username.', array('%s' => variable_get('site_name', 'local'))));
  }
  $output .= form_password(t('Password'), 'pass', $pass, 30, 64, t('Enter the password that accompanies your username.'));
  $output .= form_submit(t('Log in'));
  $items[] = l(t('Request new password'), 'user/password');
  if (variable_get('user_register', 1)) {
    $items[] = l(t('Create new account'), 'user/register');
  }
  $output .= theme('item_list', $items);

  $output  = form_group(t('User login'), $output);

  return form($output, 'post', url('user/login'));
}

function user_authenticate($name, $pass) {
  global $user;

  // Try to log in the user locally:
  $user = user_load(array('name' => $name, 'pass' => $pass, 'status' => 1));

  // Strip name and server from ID:
  if ($server = strrchr($name, '@')) {
    $name = substr($name, 0, strlen($name) - strlen($server));
    $server = substr($server, 1);
  }

  // When possible, determine corresponding external auth source. Invoke