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Drupal example source code file (install.inc)

This example Drupal source code file (install.inc) is included in the DevDaily.com "Drupal Source Code Warehouse" project. The intent of this project is to help you "Learn Drupal by Example".

PHP - Drupal tags/keywords

array, database, directory, false, file, foreach, function, if, module, php, return, schema, the, variable

The install.inc Drupal example source code

<?php
// $Id: install.inc,v 1.152 2011/01/02 17:23:20 webchick Exp $

/**
 * Indicates that a module has not been installed yet.
 */
define('SCHEMA_UNINSTALLED', -1);

/**
 * Indicates that a module has been installed.
 */
define('SCHEMA_INSTALLED', 0);

/**
 * Requirement severity -- Informational message only.
 */
define('REQUIREMENT_INFO', -1);

/**
 * Requirement severity -- Requirement successfully met.
 */
define('REQUIREMENT_OK', 0);

/**
 * Requirement severity -- Warning condition; proceed but flag warning.
 */
define('REQUIREMENT_WARNING', 1);

/**
 * Requirement severity -- Error condition; abort installation.
 */
define('REQUIREMENT_ERROR', 2);

/**
 * File permission check -- File exists.
 */
define('FILE_EXIST', 1);

/**
 * File permission check -- File is readable.
 */
define('FILE_READABLE', 2);

/**
 * File permission check -- File is writable.
 */
define('FILE_WRITABLE', 4);

/**
 * File permission check -- File is executable.
 */
define('FILE_EXECUTABLE', 8);

/**
 * File permission check -- File does not exist.
 */
define('FILE_NOT_EXIST', 16);

/**
 * File permission check -- File is not readable.
 */
define('FILE_NOT_READABLE', 32);

/**
 * File permission check -- File is not writable.
 */
define('FILE_NOT_WRITABLE', 64);

/**
 * File permission check -- File is not executable.
 */
define('FILE_NOT_EXECUTABLE', 128);

/**
 * Initialize the update system by loading all installed module's .install files.
 */
function drupal_load_updates() {
  foreach (drupal_get_installed_schema_version(NULL, FALSE, TRUE) as $module => $schema_version) {
    if ($schema_version > -1) {
      module_load_install($module);
    }
  }
}

/**
 * Returns an array of available schema versions for a module.
 *
 * @param $module
 *   A module name.
 * @return
 *   If the module has updates, an array of available updates sorted by version.
 *   Otherwise, FALSE.
 */
function drupal_get_schema_versions($module) {
  $updates = &drupal_static(__FUNCTION__, NULL);
  if (!isset($updates[$module])) {
    $updates = array();

    foreach (module_list() as $loaded_module) {
      $updates[$loaded_module] = array();
    }

    // Prepare regular expression to match all possible defined hook_update_N().
    $regexp = '/^(?P<module>.+)_update_(?P<version>\d+)$/';
    $functions = get_defined_functions();
    // Narrow this down to functions ending with an integer, since all
    // hook_update_N() functions end this way, and there are other
    // possible functions which match '_update_'. We use preg_grep() here
    // instead of foreaching through all defined functions, since the loop
    // through all PHP functions can take significant page execution time
    // and this function is called on every administrative page via
    // system_requirements().
    foreach (preg_grep('/_\d+$/', $functions['user']) as $function) {
      // If this function is a module update function, add it to the list of
      // module updates.
      if (preg_match($regexp, $function, $matches)) {
        $updates[$matches['module']][] = $matches['version'];
      }
    }
    // Ensure that updates are applied in numerical order.
    foreach ($updates as &$module_updates) {
      sort($module_updates, SORT_NUMERIC);
    }
  }
  return empty($updates[$module]) ? FALSE : $updates[$module];
}

/**
 * Returns the currently installed schema version for a module.
 *
 * @param $module
 *   A module name.
 * @param $reset
 *   Set to TRUE after modifying the system table.
 * @param $array
 *   Set to TRUE if you want to get information about all modules in the
 *   system.
 * @return
 *   The currently installed schema version, or SCHEMA_UNINSTALLED if the
 *   module is not installed.
 */
function drupal_get_installed_schema_version($module, $reset = FALSE, $array = FALSE) {
  static $versions = array();

  if ($reset) {
    $versions = array();
  }

  if (!$versions) {
    $versions = array();
    $result = db_query("SELECT name, schema_version FROM {system} WHERE type = :type", array(':type' => 'module'));
    foreach ($result as $row) {
      $versions[$row->name] = $row->schema_version;
    }
  }

  if ($array) {
    return $versions;
  }
  else {
    return isset($versions[$module]) ? $versions[$module] : SCHEMA_UNINSTALLED;
  }
}

/**
 * Update the installed version information for a module.
 *
 * @param $module
 *   A module name.
 * @param $version
 *   The new schema version.
 */
function drupal_set_installed_schema_version($module, $version) {
  db_update('system')
    ->fields(array('schema_version' => $version))
    ->condition('name', $module)
    ->execute();

  // Reset the static cache of module schema versions.
  drupal_get_installed_schema_version(NULL, TRUE);
}

/**
 * Loads the install profile, extracting its defined distribution name.
 *
 * @return
 *   The distribution name defined in the profile's .info file. Defaults to
 *   "Drupal" if none is explicitly provided by the install profile.
 *
 * @see install_profile_info()
 */
function drupal_install_profile_distribution_name() {
  // During installation, the profile information is stored in the global
  // installation state (it might not be saved anywhere yet).
  if (drupal_installation_attempted()) {
    global $install_state;
    return $install_state['profile_info']['distribution_name'];
  }
  // At all other times, we load the profile via standard methods.
  else {
    $profile = drupal_get_profile();
    $info = install_profile_info($profile);
    return $info['distribution_name'];
  }
}

/**
 * Auto detect the base_url with PHP predefined variables.
 *
 * @param $file
 *   The name of the file calling this function so we can strip it out of
 *   the URI when generating the base_url.
 * @return
 *   The auto-detected $base_url that should be configured in settings.php
 */
function drupal_detect_baseurl($file = 'install.php') {
  $proto = $_SERVER['HTTPS'] ? 'https://' : 'http://';
  $host = $_SERVER['SERVER_NAME'];
  $port = ($_SERVER['SERVER_PORT'] == 80 ? '' : ':' . $_SERVER['SERVER_PORT']);
  $uri = preg_replace("/\?.*/", '', $_SERVER['REQUEST_URI']);
  $dir = str_replace("/$file", '', $uri);

  return "$proto$host$port$dir";
}

/**
 * Detect all supported databases that are compiled into PHP.
 *
 * @return
 *  An array of database types compiled into PHP.
 */
function drupal_detect_database_types() {
  $databases = drupal_get_database_types();

  foreach ($databases as $driver => $installer) {
    $databases[$driver] = $installer->name();
  }

  return $databases;
}

/**
 * Return all supported database installer objects that are compiled into PHP.
 *
 * @return
 *  An array of database installer objects compiled into PHP.
 */
function drupal_get_database_types() {
  $databases = array();

  // We define a driver as a directory in /includes/database that in turn
  // contains a database.inc file. That allows us to drop in additional drivers
  // without modifying the installer.
  // Because we have no registry yet, we need to also include the install.inc
  // file for the driver explicitly.
  require_once DRUPAL_ROOT . '/includes/database/database.inc';
  foreach (file_scan_directory(DRUPAL_ROOT . '/includes/database', '/^[a-z]*$/i', array('recurse' => FALSE)) as $file) {
    if (file_exists($file->uri . '/database.inc') && file_exists($file->uri . '/install.inc')) {
      $drivers[$file->filename] = $file->uri;
    }
  }

  foreach ($drivers as $driver => $file) {
    $installer = db_installer_object($driver);
    if ($installer->installable()) {
      $databases[$driver] = $installer;
    }
  }

  // Usability: unconditionally put the MySQL driver on top.
  if (isset($databases['mysql'])) {
    $mysql_database = $databases['mysql'];
    unset($databases['mysql']);
    $databases = array('mysql' => $mysql_database) + $databases;
  }

  return $databases;
}

/**
 * Database installer structure.
 *
 * Defines basic Drupal requirements for databases.
 */
abstract class DatabaseTasks {

  /**
   * Structure that describes each task to run.
   *
   * @var array
   *
   * Each value of the tasks array is an associative array defining the function
   * to call (optional) and any arguments to be passed to the function.
   */
  protected $tasks = array(
    array(
      'function'    => 'checkEngineVersion',
      'arguments'   => array(),
    ),
    array(
      'arguments'   => array(
        'CREATE TABLE {drupal_install_test} (id int NULL)',
        'Drupal can use CREATE TABLE database commands.',
        'Failed to <strong>CREATE</strong> a test table on your database server with the command %query. The server reports the following message: %error.<p>Are you sure the configured username has the necessary permissions to create tables in the database?</p>',
        TRUE,
      ),
    ),
    array(
      'arguments'   => array(
        'INSERT INTO {drupal_install_test} (id) VALUES (1)',
        'Drupal can use INSERT database commands.',
        'Failed to <strong>INSERT</strong> a value into a test table on your database server. We tried inserting a value with the command %query and the server reported the following error: %error.',
      ),
    ),
    array(
      'arguments'   => array(
        'UPDATE {drupal_install_test} SET id = 2',
        'Drupal can use UPDATE database commands.',
        'Failed to <strong>UPDATE</strong> a value in a test table on your database server. We tried updating a value with the command %query and the server reported the following error: %error.',
      ),
    ),
    array(
      'arguments'   => array(
        'DELETE FROM {drupal_install_test}',
        'Drupal can use DELETE database commands.',
        'Failed to <strong>DELETE</strong> a value from a test table on your database server. We tried deleting a value with the command %query and the server reported the following error: %error.',
      ),
    ),
    array(
      'arguments'   => array(
        'DROP TABLE {drupal_install_test}',
        'Drupal can use DROP TABLE database commands.',
        'Failed to <strong>DROP</strong> a test table from your database server. We tried dropping a table with the command %query and the server reported the following error %error.',
      ),
    ),
  );

  /**
   * Results from tasks.
   *
   * @var array
   */
  protected $results = array();

  /**
   * Ensure the PDO driver is supported by the version of PHP in use.
   */
  protected function hasPdoDriver() {
    return in_array($this->pdoDriver, PDO::getAvailableDrivers());
  }

  /**
   * Assert test as failed.
   */
  protected function fail($message) {
    $this->results[$message] = FALSE;
  }

  /**
   * Assert test as a pass.
   */
  protected function pass($message) {
    $this->results[$message] = TRUE;
  }

  /**
   * Check whether Drupal is installable on the database.
   */
  public function installable() {
    return $this->hasPdoDriver() && empty($this->error);
  }

  /**
   * Return the human-readable name of the driver.
   */
  abstract public function name();

  /**
   * Return the minimum required version of the engine.
   *
   * @return
   *   A version string. If not NULL, it will be checked against the version
   *   reported by the Database engine using version_compare().
   */
  public function minimumVersion() {
    return NULL;
  }

  /**
   * Run database tasks and tests to see if Drupal can run on the database.
   */
  public function runTasks() {
    // We need to establish a connection before we can run tests.
    if ($this->connect()) {
      foreach ($this->tasks as $task) {
        if (!isset($task['function'])) {
          $task['function'] = 'runTestQuery';
        }
        if (method_exists($this, $task['function'])) {
          // Returning false is fatal. No other tasks can run.
          if (FALSE === call_user_func_array(array($this, $task['function']), $task['arguments'])) {
            break;
          }
        }
        else {
          throw new DatabaseTaskException(st("Failed to run all tasks against the database server. The task %task wasn't found.", array('%task' => $task['function'])));
        }
      }
    }
    // Check for failed results and compile message
    $message = '';
    foreach ($this->results as $result => $success) {
      if (!$success) {
        $message .= '<p class="error">' . $result  . '</p>';
      }
    }
    if (!empty($message)) {
      $message = '<p>In order for Drupal to work, and to continue with the installation process, you must resolve all issues reported below. For more help with configuring your database server, see the <a href="http://drupal.org/getting-started/install">installation handbook</a>. If you are unsure what any of this means you should probably contact your hosting provider.</p>' . $message;
      throw new DatabaseTaskException($message);
    }
  }

  /**
   * Check if we can connect to the database.
   */
  protected function connect() {
    try {
      // This doesn't actually test the connection.
      db_set_active();
      // Now actually do a check.
      Database::getConnection();
      $this->pass('Drupal can CONNECT to the database ok.');
    }
    catch (Exception $e) {
      $this->fail(st('Failed to connect to your database server. The server reports the following message: %error.<ul><li>Is the database server running?</li><li>Does the database exist, and have you entered the correct database name?</li><li>Have you entered the correct username and password?</li><li>Have you entered the correct database hostname?</li></ul>', array('%error' => $e->getMessage())));
      return FALSE;
    }
    return TRUE;
  }

  /**
   * Run SQL tests to ensure the database can execute commands with the current user.
   */
  protected function runTestQuery($query, $pass, $fail, $fatal = FALSE) {
    try {
      db_query($query);
      $this->pass(st($pass));
    }
    catch (Exception $e) {
      $this->fail(st($fail, array('%query' => $query, '%error' => $e->getMessage(), '%name' => $this->name())));
      return !$fatal;
    }
  }

  /**
   * Check the engine version.
   */
  protected function checkEngineVersion() {
    if ($this->minimumVersion() && version_compare(Database::getConnection()->version(), $this->minimumVersion(), '<')) {
      $this->fail(st("The database version %version is less than the minimum required version %minimum_version.", array('%version' => Database::getConnection()->version(), '%minimum_version' => $this->minimumVersion())));
    }
  }

  /**
   * Return driver specific configuration options.
   *
   * @param $database
   *  An array of driver specific configuration options.
   *
   * @return
   *   The options form array.
   */
  public function getFormOptions($database) {
    $form['database'] = array(
      '#type' => 'textfield',
      '#title' => st('Database name'),
      '#default_value' => empty($database['database']) ? '' : $database['database'],
      '#size' => 45,
      '#required' => TRUE,
      '#description' => st('The name of the database your @drupal data will be stored in. It must exist on your server before @drupal can be installed.', array('@drupal' => drupal_install_profile_distribution_name())),
    );

    $form['username'] = array(
      '#type' => 'textfield',
      '#title' => st('Database username'),
      '#default_value' => empty($database['username']) ? '' : $database['username'],
      '#required' => TRUE,
      '#size' => 45,
    );

    $form['password'] = array(
      '#type' => 'password',
      '#title' => st('Database password'),
      '#default_value' => empty($database['password']) ? '' : $database['password'],
      '#required' => FALSE,
      '#size' => 45,
    );

    $form['advanced_options'] = array(
      '#type' => 'fieldset',
      '#title' => st('Advanced options'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#description' => st("These options are only necessary for some sites. If you're not sure what you should enter here, leave the default settings or check with your hosting provider."),
      '#weight' => 10,
    );

    $profile = drupal_get_profile();
    $db_prefix = ($profile == 'standard') ? 'drupal_' : $profile . '_';
    $form['advanced_options']['db_prefix'] = array(
      '#type' => 'textfield',
      '#title' => st('Table prefix'),
      '#default_value' => '',
      '#size' => 45,
      '#description' => st('If more than one application will be sharing this database, enter a table prefix such as %prefix for your @drupal site here.', array('@drupal' => drupal_install_profile_distribution_name(), '%prefix' => $db_prefix)),
      '#weight' => 10,
    );

    $form['advanced_options']['host'] = array(
      '#type' => 'textfield',
      '#title' => st('Database host'),
      '#default_value' => empty($database['host']) ? 'localhost' : $database['host'],
      '#size' => 45,
      // Hostnames can be 255 characters long.
      '#maxlength' => 255,
      '#required' => TRUE,
      '#description' => st('If your database is located on a different server, change this.'),
    );

    $form['advanced_options']['port'] = array(
      '#type' => 'textfield',
      '#title' => st('Database port'),
      '#default_value' => empty($database['port']) ? '' : $database['port'],
      '#size' => 45,
      // The maximum port number is 65536, 5 digits.
      '#maxlength' => 5,
      '#description' => st('If your database server is listening to a non-standard port, enter its number.'),
    );

    return $form;
  }

  /**
   * Validates driver specific configuration settings.
   *
   * Checks to ensure correct basic database settings and that a proper
   * connection to the database can be established.
   *
   * @param $database
   *   An array of driver specific configuration options.
   * 
   * @return
   *   An array of driver configuration errors, keyed by form element name.
   */
  public function validateDatabaseSettings($database) {
    $errors = array();

    // Verify the table prefix.
    if (!empty($database['prefix']) && is_string($database['prefix']) && !preg_match('/^[A-Za-z0-9_.]+$/', $database['prefix'])) {
      $errors[$database['driver'] . '][advanced_options][db_prefix'] = st('The database table prefix you have entered, %prefix, is invalid. The table prefix can only contain alphanumeric characters, periods, or underscores.', array('%prefix' => $database['prefix']));
    }

    // Verify the database port.
    if (!empty($database['port']) && !is_numeric($database['port'])) {
      $errors[$database['driver'] . '][advanced_options][port'] =  st('Database port must be a number.');
    }

    return $errors;
  }

}

/**
 * @class Exception class used to throw error if the DatabaseInstaller fails.
 */
class DatabaseTaskException extends Exception {
}

/**
 * Replace values in settings.php with values in the submitted array.
 *
 * @param $settings
 *   An array of settings that need to be updated.
 */
function drupal_rewrite_settings($settings = array(), $prefix = '') {
  $default_settings = 'sites/default/default.settings.php';
  drupal_static_reset('conf_path');
  $settings_file = conf_path(FALSE) . '/' . $prefix . 'settings.php';

  // Build list of setting names and insert the values into the global namespace.
  $keys = array();
  foreach ($settings as $setting => $data) {
    $GLOBALS[$setting] = $data['value'];
    $keys[] = $setting;
  }

  $buffer = NULL;
  $first = TRUE;
  if ($fp = fopen(DRUPAL_ROOT . '/' . $default_settings, 'r')) {
    // Step line by line through settings.php.
    while (!feof($fp)) {
      $line = fgets($fp);
      if ($first && substr($line, 0, 5) != '<?php') {
        $buffer = "<?php\n\n";
      }
      $first = FALSE;
      // Check for constants.
      if (substr($line, 0, 7) == 'define(') {
        preg_match('/define\(\s*[\'"]([A-Z_-]+)[\'"]\s*,(.*?)\);/', $line, $variable);
        if (in_array($variable[1], $keys)) {
          $setting = $settings[$variable[1]];
          $buffer .= str_replace($variable[2], " '" . $setting['value'] . "'", $line);
          unset($settings[$variable[1]]);
          unset($settings[$variable[2]]);
        }
        else {
          $buffer .= $line;
        }
      }
      // Check for variables.
      elseif (substr($line, 0, 1) == '$') {
        preg_match('/\$([^ ]*) /', $line, $variable);
        if (in_array($variable[1], $keys)) {
          // Write new value to settings.php in the following format:
          //    $'setting' = 'value'; // 'comment'
          $setting = $settings[$variable[1]];
          $buffer .= '$' . $variable[1] . " = " . var_export($setting['value'], TRUE) . ";" . (!empty($setting['comment']) ? ' // ' . $setting['comment'] . "\n" : "\n");
          unset($settings[$variable[1]]);
        }
        else {
          $buffer .= $line;
        }
      }
      else {
        $buffer .= $line;
      }
    }
    fclose($fp);

    // Add required settings that were missing from settings.php.
    foreach ($settings as $setting => $data) {
      if ($data['required']) {
        $buffer .= "\$$setting = " . var_export($data['value'], TRUE) . ";\n";
      }
    }

    $fp = fopen(DRUPAL_ROOT . '/' . $settings_file, 'w');
    if ($fp && fwrite($fp, $buffer) === FALSE) {
      throw new Exception(st('Failed to modify %settings. Verify the file permissions.', array('%settings' => $settings_file)));
    }
  }
  else {
    throw new Exception(st('Failed to open %settings. Verify the file permissions.', array('%settings' => $default_settings)));
  }
}

/**
 * Verify an install profile for installation.
 *
 * @param $install_state
 *   An array of information about the current installation state.
 * @return
 *   The list of modules to install.
 */
function drupal_verify_profile($install_state) {
  $profile = $install_state['parameters']['profile'];
  $locale = $install_state['parameters']['locale'];

  include_once DRUPAL_ROOT . '/includes/file.inc';
  include_once DRUPAL_ROOT . '/includes/common.inc';

  $profile_file = DRUPAL_ROOT . "/profiles/$profile/$profile.profile";

  if (!isset($profile) || !file_exists($profile_file)) {
    throw new Exception(install_no_profile_error());
  }
  $info = $install_state['profile_info'];

  // Get a list of modules that exist in Drupal's assorted subdirectories.
  $present_modules = array();
  foreach (drupal_system_listing('/^' . DRUPAL_PHP_FUNCTION_PATTERN . '\.module$/', 'modules', 'name', 0) as $present_module) {
    $present_modules[] = $present_module->name;
  }

  // The install profile is also a module, which needs to be installed after all the other dependencies
  // have been installed.
  $present_modules[] = drupal_get_profile();

  // Verify that all of the profile's required modules are present.
  $missing_modules = array_diff($info['dependencies'], $present_modules);

  $requirements = array();

  if (count($missing_modules)) {
    $modules = array();
    foreach ($missing_modules as $module) {
      $modules[] = '<span class="admin-missing">' . drupal_ucfirst($module) . '</span>';
    }
    $requirements['required_modules'] = array(
      'title'       => st('Required modules'),
      'value'       => st('Required modules not found.'),
      'severity'    => REQUIREMENT_ERROR,
      'description' => st('The following modules are required but were not found. Move them into the appropriate modules subdirectory, such as <em>sites/all/modules</em>. Missing modules: !modules', array('!modules' => implode(', ', $modules))),
    );
  }
  return $requirements;
}

/**
 * Callback to install the system module.
 *
 * Separated from the installation of other modules so core system
 * functions can be made available while other modules are installed.
 */
function drupal_install_system() {
  $system_path = drupal_get_path('module', 'system');
  require_once DRUPAL_ROOT . '/' . $system_path . '/system.install';
  module_invoke('system', 'install');

  $system_versions = drupal_get_schema_versions('system');
  $system_version = $system_versions ? max($system_versions) : SCHEMA_INSTALLED;
  db_insert('system')
    ->fields(array('filename', 'name', 'type', 'owner', 'status', 'schema_version', 'bootstrap'))
    ->values(array(
        'filename' => $system_path . '/system.module',
        'name' => 'system',
        'type' => 'module',
        'owner' => '',
        'status' => 1,
        'schema_version' => $system_version,
        'bootstrap' => 0,
      ))
    ->execute();
  system_rebuild_module_data();
}

/**
 * Uninstalls a given list of modules.
 *
 * @param $module_list
 *   The modules to uninstall.
 * @param $uninstall_dependents
 *   If TRUE, the function will check that all modules which depend on the
 *   passed-in module list either are already uninstalled or contained in the
 *   list, and it will ensure that the modules are uninstalled in the correct
 *   order. This incurs a significant performance cost, so use FALSE if you
 *   know $module_list is already complete and in the correct order.
 *
 * @return
 *   FALSE if one or more dependent modules are missing from the list, TRUE
 *   otherwise.
 */
function drupal_uninstall_modules($module_list = array(), $uninstall_dependents = TRUE) {
  if ($uninstall_dependents) {
    // Get all module data so we can find dependents and sort.
    $module_data = system_rebuild_module_data();
    // Create an associative array with weights as values.
    $module_list = array_flip(array_values($module_list));

    $profile = drupal_get_profile();
    while (list($module) = each($module_list)) {
      if (!isset($module_data[$module]) || drupal_get_installed_schema_version($module) == SCHEMA_UNINSTALLED) {
        // This module doesn't exist or is already uninstalled, skip it.
        unset($module_list[$module]);
        continue;
      }
      $module_list[$module] = $module_data[$module]->sort;

      // If the module has any dependents which are not already uninstalled and
      // not included in the passed-in list, abort. It is not safe to uninstall
      // them automatically because uninstalling a module is a destructive
      // operation.
      foreach (array_keys($module_data[$module]->required_by) as $dependent) {
        if (!isset($module_list[$dependent]) && drupal_get_installed_schema_version($dependent) != SCHEMA_UNINSTALLED && $dependent != $profile) {
          return FALSE;
        }
      }
    }

    // Sort the module list by pre-calculated weights.
    asort($module_list);
    $module_list = array_keys($module_list);
  }

  foreach ($module_list as $module) {
    // First, retrieve all the module's menu paths from db.
    drupal_load('module', $module);
    $paths = module_invoke($module, 'menu');

    // Uninstall the module.
    module_load_install($module);
    module_invoke($module, 'uninstall');
    drupal_uninstall_schema($module);

    watchdog('system', '%module module uninstalled.', array('%module' => $module), WATCHDOG_INFO);

    // Now remove the menu links for all paths declared by this module.
    if (!empty($paths)) {
      $paths = array_keys($paths);
      // Clean out the names of load functions.
      foreach ($paths as $index => $path) {
        $parts = explode('/', $path, MENU_MAX_PARTS);
        foreach ($parts as $k => $part) {
          if (preg_match('/^%[a-z_]*$/', $part)) {
            $parts[$k] = '%';
          }
        }
        $paths[$index] = implode('/', $parts);
      }

      $result = db_select('menu_links')
        ->fields('menu_links')
        ->condition('router_path', $paths, 'IN')
        ->condition('external', 0)
        ->orderBy('depth')
        ->execute();
      // Remove all such items. Starting from those with the greatest depth will
      // minimize the amount of re-parenting done by menu_link_delete().
      foreach ($result as $item) {
        _menu_delete_item($item, TRUE);
      }
    }

    drupal_set_installed_schema_version($module, SCHEMA_UNINSTALLED);
  }

  if (!empty($module_list)) {
    // Call hook_module_uninstall to let other modules act
    module_invoke_all('modules_uninstalled', $module_list);
  }

  return TRUE;
}

/**
 * Verify the state of the specified file.
 *
 * @param $file
 *   The file to check for.
 * @param $mask
 *   An optional bitmask created from various FILE_* constants.
 * @param $type
 *   The type of file. Can be file (default), dir, or link.
 * @return
 *   TRUE on success or FALSE on failure. A message is set for the latter.
 */
function drupal_verify_install_file($file, $mask = NULL, $type = 'file') {
  $return = TRUE;
  // Check for files that shouldn't be there.
  if (isset($mask) && ($mask & FILE_NOT_EXIST) && file_exists($file)) {
    return FALSE;
  }
  // Verify that the file is the type of file it is supposed to be.
  if (isset($type) && file_exists($file)) {
    $check = 'is_' . $type;
    if (!function_exists($check) || !$check($file)) {
      $return = FALSE;
    }
  }

  // Verify file permissions.
  if (isset($mask)) {
    $masks = array(FILE_EXIST, FILE_READABLE, FILE_WRITABLE, FILE_EXECUTABLE, FILE_NOT_READABLE, FILE_NOT_WRITABLE, FILE_NOT_EXECUTABLE);
    foreach ($masks as $current_mask) {
      if ($mask & $current_mask) {
        switch ($current_mask) {
          case FILE_EXIST:
            if (!file_exists($file)) {
              if ($type == 'dir') {
                drupal_install_mkdir($file, $mask);
              }
              if (!file_exists($file)) {
                $return = FALSE;
              }
            }
            break;
          case FILE_READABLE:
            if (!is_readable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
          case FILE_WRITABLE:
            if (!is_writable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
          case FILE_EXECUTABLE:
            if (!is_executable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
          case FILE_NOT_READABLE:
            if (is_readable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
          case FILE_NOT_WRITABLE:
            if (is_writable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
          case FILE_NOT_EXECUTABLE:
            if (is_executable($file) && !drupal_install_fix_file($file, $mask)) {
              $return = FALSE;
            }
            break;
        }
      }
    }
  }
  return $return;
}

/**
 * Create a directory with specified permissions.
 *
 * @param $file
 *  The name of the directory to create;
 * @param $mask
 *  The permissions of the directory to create.
 * @param $message
 *  (optional) Whether to output messages. Defaults to TRUE.
 * @return
 *  TRUE/FALSE whether or not the directory was successfully created.
 */
function drupal_install_mkdir($file, $mask, $message = TRUE) {
  $mod = 0;
  $masks = array(FILE_READABLE, FILE_WRITABLE, FILE_EXECUTABLE, FILE_NOT_READABLE, FILE_NOT_WRITABLE, FILE_NOT_EXECUTABLE);
  foreach ($masks as $m) {
    if ($mask & $m) {
      switch ($m) {
        case FILE_READABLE:
          $mod |= 0444;
          break;
        case FILE_WRITABLE:
          $mod |= 0222;
          break;
        case FILE_EXECUTABLE:
          $mod |= 0111;
          break;
      }
    }
  }

  if (@drupal_mkdir($file, $mod)) {
    return TRUE;
  }
  else {
    return FALSE;
  }
}

/**
 * Attempt to fix file permissions.
 *
 * The general approach here is that, because we do not know the security
 * setup of the webserver, we apply our permission changes to all three
 * digits of the file permission (i.e. user, group and all).
 *
 * To ensure that the values behave as expected (and numbers don't carry
 * from one digit to the next) we do the calculation on the octal value
 * using bitwise operations. This lets us remove, for example, 0222 from
 * 0700 and get the correct value of 0500.
 *
 * @param $file
 *  The name of the file with permissions to fix.
 * @param $mask
 *  The desired permissions for the file.
 * @param $message
 *  (optional) Whether to output messages. Defaults to TRUE.
 * @return
 *  TRUE/FALSE whether or not we were able to fix the file's permissions.
 */
function drupal_install_fix_file($file, $mask, $message = TRUE) {
  // If $file does not exist, fileperms() issues a PHP warning.
  if (!file_exists($file)) {
    return FALSE;
  }

  $mod = fileperms($file) & 0777;
  $masks = array(FILE_READABLE, FILE_WRITABLE, FILE_EXECUTABLE, FILE_NOT_READABLE, FILE_NOT_WRITABLE, FILE_NOT_EXECUTABLE);

  // FILE_READABLE, FILE_WRITABLE, and FILE_EXECUTABLE permission strings
  // can theoretically be 0400, 0200, and 0100 respectively, but to be safe
  // we set all three access types in case the administrator intends to
  // change the owner of settings.php after installation.
  foreach ($masks as $m) {
    if ($mask & $m) {
      switch ($m) {
        case FILE_READABLE:
          if (!is_readable($file)) {
            $mod |= 0444;
          }
          break;
        case FILE_WRITABLE:
          if (!is_writable($file)) {
            $mod |= 0222;
          }
          break;
        case FILE_EXECUTABLE:
          if (!is_executable($file)) {
            $mod |= 0111;
          }
          break;
        case FILE_NOT_READABLE:
          if (is_readable($file)) {
            $mod &= ~0444;
          }
          break;
        case FILE_NOT_WRITABLE:
          if (is_writable($file)) {
            $mod &= ~0222;
          }
          break;
        case FILE_NOT_EXECUTABLE:
          if (is_executable($file)) {
            $mod &= ~0111;
          }
          break;
      }
    }
  }

  // chmod() will work if the web server is running as owner of the file.
  // If PHP safe_mode is enabled the currently executing script must also
  // have the same owner.
  if (@chmod($file, $mod)) {
    return TRUE;
  }
  else {
    return FALSE;
  }
}


/**
 * Send the user to a different installer page.
 *
 * This issues an on-site HTTP redirect. Messages (and errors) are erased.
 *
 * @param $path
 *   An installer path.
 */
function install_goto($path) {
  global $base_url;
  include_once DRUPAL_ROOT . '/includes/common.inc';
  header('Location: ' . $base_url . '/' . $path);
  header('Cache-Control: no-cache'); // Not a permanent redirect.
  drupal_exit();
}

/**
 * Functional equivalent of t(), used when some systems are not available.
 *
 * Used during the install process, when database, theme, and localization
 * system is possibly not yet available.
 *
 * @see t()
 * @ingroup sanitization
 */
function st($string, array $args = array(), array $options = array()) {
  static $locale_strings = NULL;
  global $install_state;

  if (empty($options['context'])) {
    $options['context'] = '';
  }

  if (!isset($locale_strings)) {
    $locale_strings = array();
    if (isset($install_state['parameters']['profile']) && isset($install_state['parameters']['locale'])) {
      // If the given locale was selected, there should be at least one .po file
      // with its name ending in {$install_state['parameters']['locale']}.po
      // This might or might not be the entire filename. It is also possible
      // that multiple files end with the same extension, even if unlikely.
      $po_files = file_scan_directory('./profiles/' . $install_state['parameters']['profile'] . '/translations', '/'. $install_state['parameters']['locale'] .'\.po$/', array('recurse' => FALSE));
      if (count($po_files)) {
        require_once DRUPAL_ROOT . '/includes/locale.inc';
        foreach ($po_files as $po_file) {
          _locale_import_read_po('mem-store', $po_file);
        }
        $locale_strings = _locale_import_one_string('mem-report');
      }
    }
  }

  require_once DRUPAL_ROOT . '/includes/theme.inc';
  // Transform arguments before inserting them
  foreach ($args as $key => $value) {
    switch ($key[0]) {
      // Escaped only
      case '@':
        $args[$key] = check_plain($value);
        break;
      // Escaped and placeholder
      case '%':
      default:
        $args[$key] = '<em>' . check_plain($value) . '</em>';
        break;
      // Pass-through
      case '!':
    }
  }
  return strtr((!empty($locale_strings[$options['context']][$string]) ? $locale_strings[$options['context']][$string] : $string), $args);
}

/**
 * Check an install profile's requirements.
 *
 * @param $profile
 *   Name of install profile to check.
 * @return
 *   Array of the install profile's requirements.
 */
function drupal_check_profile($profile) {
  include_once DRUPAL_ROOT . '/includes/file.inc';

  $profile_file = DRUPAL_ROOT . "/profiles/$profile/$profile.profile";

  if (!isset($profile) || !file_exists($profile_file)) {
    throw new Exception(install_no_profile_error());
  }

  $info = install_profile_info($profile);

  // Collect requirement testing results.
  $requirements = array();
  foreach ($info['dependencies'] as $module) {
    module_load_install($module);
    $function = $module . '_requirements';
    if (function_exists($function)) {
      $requirements = array_merge($requirements, $function('install'));
    }
  }
  return $requirements;
}

/**
 * Extract highest severity from requirements array.
 *
 * @param $requirements
 *   An array of requirements, in the same format as is returned by
 *   hook_requirements().
 * @return
 *   The highest severity in the array.
 */
function drupal_requirements_severity(&$requirements) {
  $severity = REQUIREMENT_OK;
  foreach ($requirements as $requirement) {
    if (isset($requirement['severity'])) {
      $severity = max($severity, $requirement['severity']);
    }
  }
  return $severity;
}

/**
 * Check a module's requirements.
 *
 * @param $module
 *   Machine name of module to check.
 * @return
 *   TRUE/FALSE depending on the requirements are in place.
 */
function drupal_check_module($module) {
  module_load_install($module);
  if (module_hook($module, 'requirements')) {
    // Check requirements
    $requirements = module_invoke($module, 'requirements', 'install');
    if (is_array($requirements) && drupal_requirements_severity($requirements) == REQUIREMENT_ERROR) {
      // Print any error messages
      foreach ($requirements as $requirement) {
        if (isset($requirement['severity']) && $requirement['severity'] == REQUIREMENT_ERROR) {
          $message = $requirement['description'];
          if (isset($requirement['value']) && $requirement['value']) {
            $message .= ' (' . t('Currently using !item !version', array('!item' => $requirement['title'], '!version' => $requirement['value'])) . ')';
          }
          drupal_set_message($message, 'error');
        }
      }
      return FALSE;
    }
  }
  return TRUE;
}

/**
 * Retrieve info about an install profile from its .info file.
 *
 * The information stored in a profile .info file is similar to that stored in
 * a normal Drupal module .info file. For example:
 * - name: The real name of the install profile for display purposes.
 * - description: A brief description of the profile.
 * - dependencies: An array of shortnames of other modules this install profile requires.
 *
 * Additional, less commonly-used information that can appear in a profile.info
 * file but not in a normal Drupal module .info file includes:
 * - distribution_name: The name of the Drupal distribution that is being
 *   installed, to be shown throughout the installation process. Defaults to
 *   'Drupal'.
 *
 * Example of .info file:
 * @code
 *    name = Minimal
 *    description = Start fresh, with only a few modules enabled.
 *    dependencies[] = block
 *    dependencies[] = dblog
 * @endcode
 *
 * @param profile
 *   Name of profile.
 * @param locale
 *   Name of locale used (if any).
 * @return
 *   The info array.
 */
function install_profile_info($profile, $locale = 'en') {
  $cache = &drupal_static(__FUNCTION__, array());

  if (!isset($cache[$profile])) {
    // Set defaults for module info.
    $defaults = array(
      'dependencies' => array(),
      'description' => '',
      'distribution_name' => 'Drupal',
      'version' => NULL,
      'hidden' => FALSE,
      'php' => DRUPAL_MINIMUM_PHP,
    );
    $info = drupal_parse_info_file("profiles/$profile/$profile.info") + $defaults;
    $info['dependencies'] = array_unique(array_merge(
      drupal_required_modules(),
      $info['dependencies'],
      ($locale != 'en' && !empty($locale) ? array('locale') : array()))
    );

    // drupal_required_modules() includes the current profile as a dependency.
    // Since a module can't depend on itself we remove that element of the array.
    array_shift($info['dependencies']);

    $cache[$profile] = $info;
  }
  return $cache[$profile];
}

/**
 * Ensures the environment for a Drupal database on a predefined connection.
 *
 * This will run tasks that check that Drupal can perform all of the functions
 * on a database, that Drupal needs. Tasks include simple checks like CREATE
 * TABLE to database specific functions like stored procedures and client
 * encoding.
 */
function db_run_tasks($driver) {
  db_installer_object($driver)->runTasks();
  return TRUE;
}

/**
 * Returns a database installer object.
 *
 * @param $driver
 *   The name of the driver.
 */
function db_installer_object($driver) {
  Database::loadDriverFile($driver, array('install.inc'));
  $task_class = 'DatabaseTasks_' . $driver;
  return new $task_class();
}

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