<?php
// $Id: environment.inc,v 1.80 2010-03-28 14:24:10 weitzman Exp $

/**
 * @file
 * Functions used by drush to query the environment and
 * setting the current configuration.
 */

/**
 * The indicator for a Drupal installation folder.
 */
define('DRUSH_DRUPAL_BOOTSTRAP', 'includes/bootstrap.inc');

/**
 * @name Drush bootstrap phases
 * @{
 * Sequential Drush bootstrapping phases.
 */

/**
 * Only bootstrap Drush, without any Drupal specific code.
 *
 * Any code that operates on the Drush installation, and not specifically
 * any Drupal directory, should bootstrap to this phase.
 */
define('DRUSH_BOOTSTRAP_DRUSH', 0);

/**
 * Set up and test for a valid drupal root, either through the -r/--root options,
 * or evaluated based on the current working directory.
 *
 * Any code that interacts with an entire Drupal installation, and not a specific
 * site on the Drupal installation should use this bootstrap phase.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_ROOT',  1);

/**
 * Set up a Drupal site directory and the correct environment variables to
 * allow Drupal to find the configuration file.
 *
 * If no site is specified with the -l / --uri options, Drush will assume the
 * site is 'default', which mimics Drupal's behaviour.
 *
 * If you want to avoid this behaviour, it is recommended that you use the
 * DRUSH_BOOTSTRAP_DRUPAL_ROOT bootstrap phase instead.
 *
 * Any code that needs to modify or interact with a specific Drupal site's
 * settings.php file should bootstrap to this phase.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_SITE', 2);

/**
 * Load the settings from the Drupal sites directory.
 *
 * This phase is analagous to the DRUPAL_BOOTSTRAP_CONFIGURATION bootstrap phase in Drupal
 * itself, and this is also the first step where Drupal specific code is included.
 *
 * This phase is commonly used for code that interacts with the Drupal install API,
 * as both install.php and update.php start at this phase.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION', 3);

/**
 * Connect to the Drupal database using the database credentials loaded
 * during the previous bootstrap phase.
 *
 * This phase is analogous to the DRUPAL_BOOTSTRAP_DATABASE bootstrap phase in
 * Drupal.
 *
 * Any code that needs to interact with the Drupal database API needs to
 * be bootstrapped to at least this phase.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_DATABASE', 4);

/**
 * Fully initialize Drupal.
 *
 * This is the default bootstrap phase all commands will try to reach,
 * unless otherwise specified.
 * This is analogous to the DRUPAL_BOOTSTRAP_FULL bootstrap phase in
 * Drupal.
 *
 * Any code that interacts with the general Drupal API should be
 * bootstrapped to this phase.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_FULL', 5);

/**
 * Log in to the initialiased Drupal site.
 *
 * This bootstrap phase is used after the site has been
 * fully bootstrapped.
 *
 * This phase will log you in to the drupal site with the username
 * or user ID specified by the --user/ -u option.
 *
 * Use this bootstrap phase for your command if you need to have access
 * to information for a specific user, such as listing nodes that might
 * be different based on who is logged in.
 */
define('DRUSH_BOOTSTRAP_DRUPAL_LOGIN', 6);

/**
 * Supported version of Console Table. This is displayed in the manual install help.
 */
define('DRUSH_TABLE_VERSION', '1.1.3');

/**
 * URL for automatic file download for supported version of Console Table.
 */
define('DRUSH_TABLE_URL', 'http://cvs.php.net/viewvc.cgi/pear/Console_Table/Table.php?revision=1.28&view=co');

/**
 * Helper function listing phases.
 *
 * For commands that need to iterate through the phases, such as help
 */
function _drush_bootstrap_phases($function_names = FALSE) {
  static $functions = array(
    DRUSH_BOOTSTRAP_DRUSH                  => '_drush_bootstrap_drush',
    DRUSH_BOOTSTRAP_DRUPAL_ROOT            => '_drush_bootstrap_drupal_root',
    DRUSH_BOOTSTRAP_DRUPAL_SITE            => '_drush_bootstrap_drupal_site',
    DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION   => '_drush_bootstrap_drupal_configuration',
    DRUSH_BOOTSTRAP_DRUPAL_DATABASE        => '_drush_bootstrap_drupal_database',
    DRUSH_BOOTSTRAP_DRUPAL_FULL            => '_drush_bootstrap_drupal_full',
    DRUSH_BOOTSTRAP_DRUPAL_LOGIN           => '_drush_bootstrap_drupal_login');
  static $phases;
  if ($function_names) {
    return $functions;
  }
  if (!$phases) {
    $phases = array_keys($functions);
  }
  return $phases;
}

/**
 * @} End of Drush bootstrap phases.
 */

/**
 * Bootstrap Drush to the desired phase.
 *
 * This function will sequentially bootstrap each
 * lower phase up to the phase that has been requested.
 *
 * @param phase
 *   The bootstrap phase to bootstrap to.
 *   Any of the following constants :
 *     DRUSH_BOOTSTRAP_DRUSH                = Only Drush.
 *     DRUSH_BOOTSTRAP_DRUPAL_ROOT          = Find a valid Drupal root.
 *     DRUSH_BOOTSTRAP_DRUPAL_SITE          = Find a valid Drupal site.
 *     DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION = Load the site's settings.
 *     DRUSH_BOOTSTRAP_DRUPAL_DATABASE      = Initialize the database.
 *     DRUSH_BOOTSTRAP_DRUPAL_FULL          = Initialize Drupal fully.
 *     DRUSH_BOOTSTRAP_DRUPAL_LOGIN         = Log into Drupal with a valid user.
 */
function drush_bootstrap($phase) {
  static $phases;
  if (!$phases) {
    $phases = _drush_bootstrap_phases(TRUE);
  }
  static $phase_index = 0;

  drush_set_context('DRUSH_BOOTSTRAPPING', TRUE);
  while ($phase >= $phase_index && isset($phases[$phase_index])) {
    if (drush_bootstrap_validate($phase_index)) {
      $current_phase = $phases[$phase_index];
      if (function_exists($current_phase) && !drush_get_error()) {
        drush_log(dt("Drush bootstrap phase : !function()", array('!function' => $current_phase)), 'bootstrap');
        $current_phase();
      }
      drush_set_context('DRUSH_BOOTSTRAP_PHASE', $phase_index);
    }
    else {
      $errors = drush_get_context('DRUSH_BOOTSTRAP_ERRORS', array());
      foreach ($errors as $code => $message) {
        drush_set_error($code, $message);
      }
    }
    unset($phases[$phase_index++]);
  }
  drush_set_context('DRUSH_BOOTSTRAPPING', FALSE);

  return !drush_get_error();
}

/**
 * Validate whether a bootstrap phases can be reached.
 *
 * This function will validate the settings that will be used
 * during the actual bootstrap process, and allow commands to
 * progressively bootstrap to the highest level that can be reached.
 *
 * This function will only run the validation function once, and
 * store the result from that execution in a local static. This avoids
 * validating phases multiple times.
 *
 * @param phase
 *   The bootstrap phase to validate to.
 *   Any of the following constants :
 *     DRUSH_BOOTSTRAP_DRUSH                = Only Drush.
 *     DRUSH_BOOTSTRAP_DRUPAL_ROOT          = Find a valid Drupal root.
 *     DRUSH_BOOTSTRAP_DRUPAL_SITE          = Find a valid Drupal site.
 *     DRUSH_BOOTSTRAP_DRUPAL_CONFIGURATION = Load the site's settings.
 *     DRUSH_BOOTSTRAP_DRUPAL_DATABASE      = Initialize the database.
 *     DRUSH_BOOTSTRAP_DRUPAL_FULL          = Initialize Drupal fully.
 *     DRUSH_BOOTSTRAP_DRUPAL_LOGIN         = Log into Drupal with a valid user.
 *
 * @return
 *   True if bootstrap is possible, False if the validation failed.
 *
 */
function drush_bootstrap_validate($phase) {
  static $phases;
  static $result_cache = array();
  if (!$phases) {
    $phases = _drush_bootstrap_phases(TRUE);
  }
  static $phase_index = 0;
  if (!array_key_exists($phase, $result_cache)) {
    drush_set_context('DRUSH_BOOTSTRAP_ERRORS', array());
    drush_set_context('DRUSH_BOOTSTRAP_VALUES', array());

    while ($phase >= $phase_index && isset($phases[$phase_index])) {
      $current_phase = $phases[$phase_index] . '_validate';
      if (function_exists($current_phase)) {
        $result_cache[$phase_index] = $current_phase();
      }
      else {
        $result_cache[$phase_index] = TRUE;
      }
      drush_set_context('DRUSH_BOOTSTRAP_VALIDATION_PHASE', $phase_index);
      unset($phases[$phase_index++]);
    }
  }
  return $result_cache[$phase];
}

/**
 * Bootstrap to the highest level possible, without triggering any errors.
 */
function drush_bootstrap_max() {
  $phases = _drush_bootstrap_phases();
  $phase_index = DRUSH_BOOTSTRAP_DRUSH;

  // Try to bootstrap to the maximum possible level, without generating errors
  foreach ($phases as $phase_index) {
    if (drush_bootstrap_validate($phase_index)) {
      if ($phase_index > drush_get_context('DRUSH_BOOTSTRAP_PHASE')) {
        drush_bootstrap($phase_index);
      }
    }
    else {
      break;
    }
  }

  return $phase_index;
}


/**
 * Helper function to collect any errors that occur during the bootstrap process.
 * Always returns FALSE, for convenience.
 */
function drush_bootstrap_error($code, $message = null) {
  $errors = drush_get_context('DRUSH_BOOTSTRAP_ERRORS');
  $errors[$code] = $message;
  drush_set_context('DRUSH_BOOTSTRAP_ERRORS', $errors);
  return FALSE;
}

/**
 * Log PHP errors to the Drush log. This is in effect until Drupal's error
 * handler takes over.
 */
function drush_error_handler($errno, $message, $filename, $line, $context) {
  // If the @ error suppression operator was used, error_reporting will have
  // been temporarily set to 0.
  if (error_reporting() == 0) {
    return;
  }

  if ($errno & (E_ALL)) {
    // By default we log notices.
    $type = drush_get_option('php-notices', 'notice');

    // Bitmask value that constitutes an error needing to be logged.
    $error = E_ERROR | E_PARSE | E_CORE_ERROR | E_COMPILE_ERROR | E_USER_ERROR;
    if ($errno & $error) {
      $type = 'error';
    }

    // Bitmask value that constitutes a warning being logged.
    $warning = E_WARNING | E_CORE_WARNING | E_COMPILE_WARNING | E_USER_WARNING;
    if ($errno & $warning) {
      $type = 'warning';
    }

    drush_log($message . ' ' . basename($filename) . ':' . $line, $type);

    return TRUE;
  }
}

/**
 * Helper function to store any context settings that are being validated.
 */
function drush_bootstrap_value($context, $value = null) {
  $values =& drush_get_context('DRUSH_BOOTSTRAP_VALUES', array());

  if (!is_null($value)) {
    $values[$context] = $value;
  }

  if (array_key_exists($context, $values)) {
    return $values[$context];
  }

  return null;
}

/**
 * Validate initial Drush bootstrap phase.
 */
function _drush_bootstrap_drush_validate() {
  // Test safe mode is off.
  if (ini_get('safe_mode')) {
    return drush_bootstrap_error('DRUSH_SAFE_MODE', dt('PHP safe mode is activated. Drush requires that safe mode is disabled.'));
  }

  // try using the PEAR installed version of Console_Table
  $tablefile = 'Console/Table.php';
  if (@file_get_contents($tablefile, FILE_USE_INCLUDE_PATH) === FALSE) {
    $tablefile = DRUSH_BASE_PATH . '/includes/table.inc';

    // Attempt to download Console Table, via various methods.
    if (!file_exists($tablefile)) {
      $targetpath = dirname($tablefile);
      // not point continuing if we can't write to the target path
      if (!is_writable($targetpath)) {
        return drush_bootstrap_error('DRUSH_TABLES_INC', dt("Drush needs a copy of the PEAR Console_Table library in order to function, and the attempt to download this file automatically failed because you do not have permission to write files in !path. To continue you will need to download the !version package from http://pear.php.net/package/Console_Table, extract it, and copy the Table.php file into Drush's directory as !tablefile.", array('!path' => $targetpath, '!version' => DRUSH_TABLE_VERSION ,'!tablefile' => $tablefile)));
      }

      if ($file = @file_get_contents(DRUSH_TABLE_URL)) {
        @file_put_contents($tablefile, $file);
      }
      if (!file_exists($tablefile)) {
        drush_shell_exec("wget -q --timeout=30 -O $tablefile " . DRUSH_TABLE_URL);
        if (!file_exists($tablefile)) {
          drush_shell_exec("curl -s  --connect-timeout 30 -o $tablefile " . DRUSH_TABLE_URL);
          if (!file_exists($tablefile)) {
            return drush_bootstrap_error('DRUSH_TABLES_INC', dt("Drush needs a copy of the PEAR Console_Table library in order to function, and the attempt to download this file automatically failed. To continue you will need to download the !version package from http://pear.php.net/package/Console_Table, extract it, and copy the Table.php file into Drush's directory as !tablefile.", array('!version' => DRUSH_TABLE_VERSION ,'!tablefile' => $tablefile)));
          }
        }
      }
    }
  }
  require_once $tablefile;

  return TRUE;
}

/**
 * Initial Drush bootstrap phase.
 *
 * During the initialization of Drush,
 * this is the first step where all we are
 * aware of is Drush itself.
 *
 * In this step we will register the shutdown function,
 * parse the command line arguments and store them in their
 * related contexts.
 *
 * Configuration files (drushrc.php) that are
 *   a) Specified on the command line
 *   b) Stored in the root directory of drush.php
 *   c) Stored in the home directory of the system user.
 *
 * Additionally the DRUSH_QUIET and DRUSH_BACKEND contexts,
 * will be evaluated now, as they need to be set very early in
 * the execution flow to be able to take affect/
 */
function _drush_bootstrap_drush() {
  // The bootstrap can fail silently, so we catch that in a shutdown function.
  register_shutdown_function('drush_shutdown');

  // Set the terminal width, used for wrapping table output.
  // Normally this is exported using tput in the drush script.
  // If this is not present we do an additional check using stty here.
  if (!($columns = getenv('COLUMNS'))) {
    exec('stty size 2>&1', $stty_output, $stty_status);
    if (!$stty_status) $columns = preg_replace('/\d+\s(\d+)/', '$1', $stty_output[0], -1, $stty_count);
    // If stty failed, or we couldn't parse it's output, we assume 80 columns.
    if ($stty_status || !$stty_count) $columns = 80;
  }
  drush_set_context('DRUSH_COLUMNS', $columns);

  // parse the command line arguments.
  drush_parse_args();

  // statically define a way to call drush again
  define('DRUSH_COMMAND', drush_find_drush());

  $drush_info = drush_read_drush_info();
  define('DRUSH_VERSION', $drush_info['version']);

  // Load a drushrc.php file in the drush.php's directory.
  drush_load_config('drush');

  // Load a drushrc.php file in the $ETC_PREFIX/etc/drush directory.
  drush_load_config('system');

  // Load a drushrc.php file in the ~/.drush directory.
  drush_load_config('user');

  // Load a custom config specified with the --config option.
  drush_load_config('custom');

  // Process the site alias that specifies which instance
  // of drush (local or remote) this command will operate on.
  // We must do this after we load our config files (so that
  // site aliases are available), but before the rest
  // of the drush and drupal root bootstrap phases are
  // done, since site aliases may set option values that
  // affect these phases.
  // TODO: Note that this function will call drush_locate_root
  // (from within _drush_sitealias_find_record_for_local_site),
  // and drush_locate_root will be called again when bootstrapping
  // the drupal root below.  Is there a good way to refactor this
  // so that we do not need to search for the root twice?
  drush_sitealias_check_arg();

  $backend = drush_set_context('DRUSH_BACKEND', drush_get_option(array('b', 'backend')));

  if ($backend) {
    // Load options passed as a JSON encoded string through STDIN.
    $stdin_options = _drush_backend_get_stdin();
    if (is_array($stdin_options)) {
      drush_set_context('stdin', $stdin_options);
    }
  }

  // Pipe implies quiet.
  $quiet = drush_set_context('DRUSH_QUIET', drush_get_option(array('q', 'quiet', 'p', 'pipe')));

  drush_set_context('DRUSH_PIPE', drush_get_option(array('p', 'pipe')));

  // When running in backend mode, all output is buffered, and returned
  // as a property of a JSON encoded associative array.
  if ($backend || $quiet) {
    ob_start();
  }

  _drush_bootstrap_global_options();

  // Find any command files that are available during this bootstrap phase.
  _drush_find_commandfiles(DRUSH_BOOTSTRAP_DRUSH);
}

function _drush_bootstrap_global_options() {
  // Debug implies verbose
  drush_set_context('DRUSH_VERBOSE',     drush_get_option(array('v', 'verbose', 'd', 'debug'), FALSE));
  drush_set_context('DRUSH_DEBUG', drush_get_option(array('d', 'debug')));


  // Backend implies affirmative
  drush_set_context('DRUSH_AFFIRMATIVE', drush_get_option(array('y', 'yes', 'b', 'backend'), FALSE));
  drush_set_context('DRUSH_NEGATIVE',    drush_get_option(array('n', 'no'), FALSE));
  drush_set_context('DRUSH_SIMULATE',    drush_get_option(array('s', 'simulate'), FALSE));

  // Suppress colored logging if --nocolor option is explicitly given or if
  // terminal does not support it.
  $nocolor = (drush_get_option(array('nocolor'), FALSE) || !getenv('TERM'));
  if (!$nocolor) {
    // Check for colorless terminal.
    $colors = exec('tput colors 2>&1');
    $nocolor = !($colors === FALSE || (is_numeric($colors) && $colors >= 3));
  }
  drush_set_context('DRUSH_NOCOLOR', $nocolor);
}

/**
 * Validate the DRUSH_BOOTSTRAP_DRUPAL_ROOT phase.
 *
 * In this function, we will check if a valid Drupal directory is available.
 * We also determine the value that will be stored in the DRUSH_DRUPAL_ROOT
 * context and DRUPAL_ROOT constant if it is considered a valid option.
 */
function _drush_bootstrap_drupal_root_validate() {
  $drupal_root = drush_get_option(array('r', 'root'), drush_locate_root());

  if (empty($drupal_root)) {
    return drush_bootstrap_error('DRUSH_NO_DRUPAL_ROOT', dt("A Drupal installation directory could not be found"));
  }
  if (!drush_valid_drupal_root($drupal_root)) {
    return drush_bootstrap_error('DRUSH_INVALID_DRUPAL_ROOT', dt("The directory !drupal_root does not contain a valid Drupal installation", array('!drupal_root' => $drupal_root)));
  }

  drush_bootstrap_value('drupal_root', $drupal_root);

  return TRUE;
}

/**
 * Bootstrap Drush with a valid Drupal Directory.
 *
 * In this function, the pwd will be moved to the root
 * of the Drupal installation.
 *
 * The DRUSH_DRUPAL_ROOT context and the DRUPAL_ROOT constant are
 * populated from the value that we determined during the validation phase.
 *
 * We also now load the drushrc.php for this specific platform.
 * We can now include files from the Drupal Tree, and figure
 * out more context about the platform, such as the version of Drupal.
 */
function _drush_bootstrap_drupal_root() {
  $drupal_root = drush_set_context('DRUSH_DRUPAL_ROOT', drush_bootstrap_value('drupal_root'));
  define('DRUPAL_ROOT', $drupal_root);

  // Save original working dir case some command wants it.
  drush_set_context('DRUSH_OLDCWD', getcwd());

  chdir($drupal_root);
  drush_load_config('drupal');
  require_once(DRUPAL_ROOT . '/' . DRUSH_DRUPAL_BOOTSTRAP);
  $version = drush_set_context('DRUSH_DRUPAL_VERSION', drush_drupal_version());
  $major_version = drush_set_context('DRUSH_DRUPAL_MAJOR_VERSION', drush_drupal_major_version());

  drush_log(dt("Initialized Drupal !version root directory at !drupal_root", array("!version" => $version, '!drupal_root' => $drupal_root)));
}

/**
 * VALIDATE the DRUSH_BOOTSTRAP_DRUPAL_SITE phase.
 *
 * In this function we determine the URL used for the command,
 * and check for a valid settings.php file.
 *
 * To do this, we need to set up the $_SERVER environment variable,
 * to allow us to use conf_path to determine what Drupal will load
 * as a configuration file.
 */
function _drush_bootstrap_drupal_site_validate() {
  $site_path = drush_site_path();
  $elements = explode('/', $site_path);
  $current = array_pop($elements);
  if (!$current) {
    $current = 'default';
  }
  $uri = 'http://'. $current;

  $drush_uri = drush_bootstrap_value('drush_uri', drush_get_option(array('l', 'uri'), $uri));

  // Fake the necessary HTTP headers that Drupal needs:
  if ($drush_uri) {
    $drupal_base_url = parse_url($drush_uri);
    // If there's no url scheme set, add http:// and re-parse the url
    // so the host and path values are set accurately.
    if (!array_key_exists('scheme', $drupal_base_url)) {
      $drush_uri = 'http://' . $drush_uri;
      $drupal_base_url = parse_url($drush_uri);
    }
    // Fill in defaults.
    $drupal_base_url += array(
      'path' => NULL,
      'host' => NULL,
    );
    $_SERVER['HTTP_HOST'] = $drupal_base_url['host'];
    $_SERVER['PHP_SELF'] = $drupal_base_url['path'] . '/index.php';
  }
  else {
    $_SERVER['HTTP_HOST'] = 'default';
    $_SERVER['PHP_SELF'] = '/index.php';
  }

  $_SERVER['REQUEST_URI'] = $_SERVER['SCRIPT_NAME'] = $_SERVER['PHP_SELF'];
  $_SERVER['REMOTE_ADDR'] = '127.0.0.1';
  $_SERVER['REQUEST_METHOD']  = NULL;
  $_SERVER['SERVER_SOFTWARE'] = NULL;
  $_SERVER['HTTP_USER_AGENT'] = NULL;

  $site = drush_bootstrap_value('site', $_SERVER['HTTP_HOST']);

  $conf_path = drush_bootstrap_value('conf_path', conf_path(TRUE, TRUE));
  $conf_file = "./$conf_path/settings.php";
  if (!file_exists($conf_file)) {
    return drush_bootstrap_error('DRUPAL_SITE_SETTINGS_NOT_FOUND', dt("Could not find a Drupal settings.php file at !file.",
       array('!file' => $conf_file)));
  }

  return TRUE;
}

/**
 * Called by _drush_bootstrap_drupal_site to do the main work
 * of the drush drupal site bootstrap.
 */
function _drush_bootstrap_do_drupal_site() {
  $drush_uri = drush_set_context('DRUSH_URI', drush_bootstrap_value('drush_uri'));
  $site = drush_set_context('DRUSH_DRUPAL_SITE', drush_bootstrap_value('site'));
  $conf_path = drush_set_context('DRUSH_DRUPAL_SITE_ROOT', drush_bootstrap_value('conf_path'));

  // Find any command files that are available during this bootstrap phase.
  _drush_find_commandfiles(DRUSH_BOOTSTRAP_DRUPAL_SITE);

  drush_log(dt("Initialized Drupal site !site at !site_root", array('!site' => $site, '!site_root' => $conf_path)));
  drush_load_config('site');
}

/**
 * Initialize a site on the Drupal root.
 *
 * We now set various contexts that we determined and confirmed to be valid.
 * Additionally we load an optional drushrc.php file in the site directory.
 */
function _drush_bootstrap_drupal_site() {
  _drush_bootstrap_do_drupal_site();
  _drush_bootstrap_redo_drupal_site();
}

/**
 * Re-do the drupal site bootstrap (and possibly the
 * drupal root bootstrap) if a site alias was processed
 * after the site bootstrap phase completed.  This will
 * happen when processing "drush sitealias command" for
 * a site alias defined in a drushrc.php file in the
 * default site's drush configuration directory.
 */
function _drush_bootstrap_redo_drupal_site() {
  // If drush_load_config defined a site alias that did not
  // exist before, then sitealias check arg might now match
  // against one of those aliases.
  if (drush_sitealias_check_arg() === TRUE) {
    $remote_host = drush_get_option('remote-host');
    if (!isset($remote_host)) {
      // Check to see if the drupal root changed.
      // If it has, we will set remote-host to cause
      // this command to be executed via the backend invoke
      // process.
      $sitealias_drupal_root = drush_get_option(array('r', 'root'));
      if (($sitealias_drupal_root != null) && (DRUPAL_ROOT != $sitealias_drupal_root)) {
        drush_set_option('remote-host', 'localhost');
      }
      else {
        // If we set an alias, then we need to bootstrap the
        // drupal site once again.  It is possible to re-bootstrap
        // the site at this point because settings.php has not
        // been included yet.
        drush_log(dt("Re-bootstrap drupal site."));
        _drush_bootstrap_drupal_site_validate();
        _drush_bootstrap_do_drupal_site();
      }
    }
  }
}

/**
 * Initialize and load the Drupal configuration files.
 *
 * We process and store a normalized set of database credentials
 * from the loaded configuration file, so we can validate them
 * and access them easily in the future.
 */
function _drush_bootstrap_drupal_configuration() {
  global $conf, $drush_conf_override;

  drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);

  // Overriding the $conf array from drupal CONFIGURATION bootstrap with the
  // Overrides we collected on the loaded config files on DRUSH_BOOTSTRAP_DRUSH
  $conf = is_array($conf) && is_array($drush_conf_override) ? array_merge($conf, $drush_conf_override) : $conf;

  // Populate the DRUSH_DB_CREDENTIALS with the fields loaded from the configuration.
  $creds = array();
  switch (drush_drupal_major_version()) {
     case 5:
     case 6:
       if (isset($GLOBALS['db_url'])) {
         $url = $GLOBALS['db_url'];
         if (is_array($url)) {
           $url = $url['default'];
         }
         $parts = parse_url($url);
         $parts += array('pass' => '', 'port' => '');
         $creds['driver'] = $parts['scheme'];
         $creds['user'] = urldecode($parts['user']);
         $creds['host'] = $parts['host'];
         $creds['port'] = $parts['port'];
         $creds['pass'] = urldecode($parts['pass']);
         $creds['name'] = trim($parts['path'], '/');
       }
       break;
     case 7:
       if (isset($GLOBALS['databases']['default']['default'])) {
         $conn = $GLOBALS['databases']['default']['default'];
         $creds['driver'] = $conn['driver'];
         $creds['user'] = $conn['username'];
         $creds['host'] = $conn['host'];
         $creds['port'] = $conn['port'];
         $creds['name'] = $conn['database'];
         $creds['pass'] = $conn['password'];
       }
       break;
  }

  drush_set_context('DRUSH_DB_CREDENTIALS', $creds);
}

/**
 * Validate the DRUSH_BOOTSTRAP_DRUPAL_DATABASE phase
 *
 * Attempt to making a working database connection using the
 * database credentials that were loaded during the previous
 * phase.
 */
function _drush_bootstrap_drupal_database_validate() {
  if (!drush_valid_db_credentials()) {
    return drush_bootstrap_error("DRUSH_DRUPAL_DB_ERROR");
  }
  return TRUE;
}

/**
 * Boostrap the Drupal database.
 */
function _drush_bootstrap_drupal_database() {
  drush_log(dt("Successfully connected to the Drupal database."), 'bootstrap');
  drupal_bootstrap(DRUPAL_BOOTSTRAP_DATABASE);
}

/**
 * Attempt to load the full Drupal system.
 */
function _drush_bootstrap_drupal_full() {
  ob_start();
  drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
  ob_end_clean();
  // Poke Drupal with a cluestick so it recognizes our system_watchdog() implementation.
  module_implements('watchdog', FALSE, TRUE);
  _drush_log_drupal_messages();
  // Find any command files that are available during this bootstrap phase.
  _drush_find_commandfiles(DRUSH_BOOTSTRAP_DRUPAL_FULL);
}

/**
 * Log into the bootstrapped Drupal site with a specific
 * username or user id.
 */
function _drush_bootstrap_drupal_login() {
  $drush_user = drush_set_context('DRUSH_USER', drush_get_option(array('u', 'user'), 0));

  drush_drupal_login($drush_user);
  _drush_log_drupal_messages();
}


/**
 * Returns the current working directory.
 *
 * TODO: Could cache result, but it isn't really expensive.
 */
function drush_cwd() {
  // We use PWD if available because getcwd() resolves symlinks, which
  // could take us outside of the Drupal root, making it impossible to find.
  // $_SERVER['PWD'] isn't set on windows and generates a Notice.
  $path = isset($_SERVER['PWD'])?$_SERVER['PWD']:'';
  if (empty($path)) {
    $path = getcwd();
  }

  // Convert windows paths.
  $path = _drush_convert_path($path);

  return $path;
}

/**
 * Converts a Windows path (dir1\dir2\dir3) into a Unix path (dir1/dir2/dir3).
 * Also converts a cygwin "drive emulation" path (/cygdrive/c/dir1) into a
 * proper drive path, still with Unix slashes (c:/dir1).
 */
function _drush_convert_path($path) {
  $path = str_replace('\\','/', $path);
  $path = preg_replace('/^\/cygdrive\/([A-Za-z])(.*)$/', '\1:\2', $path);

  return $path;
}

/**
 * Returns parent directory.
 *
 * @param string
 *   Path to start from.
 *
 * @return string
 *   Parent path of given path.
 */
function _drush_shift_path_up($path) {
  if (empty($path)) {
    return FALSE;
  }
  $path = explode('/', $path);
  // Move one directory up.
  array_pop($path);
  return implode('/', $path);
}

/**
 * Like Drupal conf_path, but searching from beneath.
 * Allows proper site uri detection in site sub-directories.
 *
 * Essentially looks for a settings.php file.
 *
 * @param string
 *   Search starting path. Defaults to current working directory.
 *
 * @return
 *   Current site path (folder containing settings.php) or FALSE if not found.
 */
function drush_site_path($path = NULL) {
  static $site_path;

  if (!isset($site_path)) {
    $site_path = FALSE;

    $path = empty($path) ? drush_cwd() : $path;
    // Check the current path.
    if (file_exists($path . '/settings.php')) {
      $site_path = $path;
    }
    else {
      // Move up dir by dir and check each.
      while ($path = _drush_shift_path_up($path)) {
        if (file_exists($path . '/settings.php')) {
          $site_path = $path;
          break;
        }
      }
    }

    $site_root = drush_locate_root();
    if (file_exists($site_root . '/sites/sites.php')) {
      $sites = array();
      // This will overwrite $sites with the desired mappings.
      include($site_root . '/sites/sites.php');
      // We do a reverse lookup here to determine the URL given the site key.
      if ($match = array_search($site_path, $sites)) {
        $site_path = $match;
      }
    }

    // Last resort: try from site root
    if (!$site_path) {
      if ($site_root) {
        if (file_exists($site_root . '/sites/default/settings.php')) {
          $site_path = $site_root . '/sites/default';
        }
      }
    }
  }

  return $site_path;
}

/**
 * Exhaustive depth-first search to try and locate the Drupal root directory.
 * This makes it possible to run drush from a subdirectory of the drupal root.
 *
 * @param
 *   Search start path. Defaults to current working directory.
 * @return
 *   A path to drupal root, or FALSE if not found.
 */
function drush_locate_root($start_path = NULL) {
  $drupal_root = FALSE;

  $start_path = empty($start_path) ? drush_cwd() : $start_path;
  foreach (array(TRUE, FALSE) as $follow_symlinks) {
    $path = $start_path;
    if ($follow_symlinks && is_link($path)) {
      $path = realpath($path);
    }
    // Check the start path.
    if (drush_valid_drupal_root($path)) {
      $drupal_root = $path;
      break;
    }
    else {
      // Move up dir by dir and check each.
      while ($path = _drush_shift_path_up($path)) {
        if ($follow_symlinks && is_link($path)) {
          $path = realpath($path);
        }
        if (drush_valid_drupal_root($path)) {
          $drupal_root = $path;
          break 2;
        }
      }
    }
  }

  return $drupal_root;
}

/**
 * Checks whether given path qualifies as a Drupal root.
 *
 * @param string
 *   Path to check.
 *
 * @return boolean
 *   True if given path seems to be a Drupal root, otherwise FALSE.
 */
function drush_valid_drupal_root($path) {
  return !empty($path) && is_dir($path) && file_exists($path . '/' . DRUSH_DRUPAL_BOOTSTRAP);
}

/**
 * Tests the currently loaded database credentials to ensure a database connection can be made.
 */
function drush_valid_db_credentials() {
  if (class_exists('PDO')) {
    $creds = drush_get_context('DRUSH_DB_CREDENTIALS');

    $type = ($creds['driver'] == 'mysqli') ? 'mysql' : $creds['driver'];

    if (!in_array($type, PDO::getAvailableDrivers())) {
      drush_log(dt('PDO support available, but the !type driver has not been installed. Assuming success.', array('!type' => $type)), 'bootstrap');
      return TRUE;
    }

    $constr = sprintf("%s:dbname=%s;host=%s", $type, $creds['name'], $creds['host']);
    if (!empty($creds['port'])) {
      $constr .= sprintf(";port=%d", $creds['port']);
    }

    try {
      $db = new PDO($constr, $creds['user'], $creds['pass']);
      $db = null;
      return TRUE;
    }
    catch (PDOException $e) {
      // We do not use drush_set_error here , because it's up to the calling function
      // to determine whether or not this is an error or a warning.
      drush_log($e->getMessage(), 'warning');
      return FALSE;
    }
  }
  else {
    drush_log(dt('PDO support not available. Could not pre-validate database credentials. Assuming success'), 'bootstrap');
    return TRUE;
  }
}

/**
 * Determine a proper way to call drush again
 *
 * This check if we were called directly or as an argument to some
 * wrapper command (php and sudo are checked now).
 *
 * Calling ./drush.php directly yields the following environment:
 *
 * _SERVER["argv"][0] => ./drush.php
 *
 * Calling php ./drush.php also yields the following:
 *
 * _SERVER["argv"][0] => ./drush.php
 *
 * Note that the $_ global is defined only in bash and therefore cannot
 * be relied upon.
 *
 * We will therefore assume PHP is available in the path and is named
 * "php" for execute ourselves. That is, the #!/usr/bin/env php is
 * working and valid, unless a PHP constant is defined, which can be
 * done by the shell wrapper.
 *
 * The DRUSH_COMMAND constant is initialised to the value of this
 * function when environment.inc is loaded.
 *
 * @see DRUSH_COMMAND
 */
function drush_find_drush() {
 $php = drush_get_option('php');
 if (isset($php)) {
    $drush = $php . " " . realpath($_SERVER['argv'][0]) . " --php=$php";
  } else {
    $drush = realpath($_SERVER['argv']['0']);
  }
  return $drush;
}

/**
 * Read the drush info file.
 */
function drush_read_drush_info() {
  $drush_info_file = dirname(__FILE__) . '/../drush.info';

  return parse_ini_file($drush_info_file);
}

/**
 * Make a determination whether or not the given
 * host is local or not.
 *
 * @param host
 *   A hostname, 'localhost' or '127.0.0.1'.
 * @return
 *   True if the host is local.
 */
function drush_is_local_host($host) {
  // @TODO: Check DNS against local interface settings?
  // (Maybe not portable, maybe too slow?)
  // @TODO: Allow user to specify host names in a configuration
  // option (e.g. $options['local-hosts'] = array('myhostname1.com', 'myhostname2.com'); )
  return ($host == 'localhost') || ($host == '127.0.0.1') || (file_exists(drush_get_context('DRUSH_DRUPAL_ROOT') . "/sites/$host"));
}

/**
 * Get complete information for all available modules and themes.
 *
 * @return
 *   An array containing info for all available modules and themes.
 */
function drush_get_projects() {
  drush_include_engine('drupal', 'environment');
  return array_merge(drush_get_modules(), drush_get_themes());
}

/**
 * Calculate a project status based on current status and schema version.
 *
 * @param $project
 *   Array of a single project info.
 *
 * @return
 *   String describing project status. Values: enabled|disabled|not installed
 */
function drush_get_project_status($project) {
  if (($project->type == 'module')&&($project->schema_version == -1)) {
    $status = "not installed";
  }
  else {
    $status = ($project->status == 1)?'enabled':'disabled';
  }

  return $status;
}

/**
 * Return the default theme.
 *
 * @return
 *  Machine name of the default theme.
 */
function drush_theme_get_default() {
  return variable_get('theme_default', 'garland');
}

/**
 * Return the administration theme.
 *
 * @return
 *  Machine name of the administration theme.
 */
function drush_theme_get_admin() {
  return variable_get('admin_theme', drush_theme_get_default());
}

/**
 * Return the user's home directory.
 */

function drush_server_home() {
  $home = NULL;
  // $_SERVER['HOME'] isn't set on windows and generates a Notice.
  if (!empty($_SERVER['HOME'])) {
    $home = $_SERVER['HOME'];
  }
  elseif (!empty($_SERVER['HOMEDRIVE']) && !empty($_SERVER['HOMEPATH'])) {
    // home on windows
    $home = $_SERVER['HOMEDRIVE'] . $_SERVER['HOMEPATH'];
  }
  return $home;
}