webmaster@1: <?php
webmaster@13: // $Id: path.inc,v 1.19.2.1 2008/10/13 21:06:41 dries Exp $
webmaster@1: 
webmaster@1: /**
webmaster@1:  * @file
webmaster@1:  * Functions to handle paths in Drupal, including path aliasing.
webmaster@1:  *
webmaster@1:  * These functions are not loaded for cached pages, but modules that need
webmaster@1:  * to use them in hook_init() or hook exit() can make them available, by
webmaster@1:  * executing "drupal_bootstrap(DRUPAL_BOOTSTRAP_PATH);".
webmaster@1:  */
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Initialize the $_GET['q'] variable to the proper normal path.
webmaster@1:  */
webmaster@1: function drupal_init_path() {
webmaster@1:   if (!empty($_GET['q'])) {
webmaster@1:     $_GET['q'] = drupal_get_normal_path(trim($_GET['q'], '/'));
webmaster@1:   }
webmaster@1:   else {
webmaster@1:     $_GET['q'] = drupal_get_normal_path(variable_get('site_frontpage', 'node'));
webmaster@1:   }
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Given an alias, return its Drupal system URL if one exists. Given a Drupal
webmaster@1:  * system URL return one of its aliases if such a one exists. Otherwise,
webmaster@1:  * return FALSE.
webmaster@1:  *
webmaster@1:  * @param $action
webmaster@1:  *   One of the following values:
webmaster@1:  *   - wipe: delete the alias cache.
webmaster@1:  *   - alias: return an alias for a given Drupal system path (if one exists).
webmaster@1:  *   - source: return the Drupal system URL for a path alias (if one exists).
webmaster@1:  * @param $path
webmaster@1:  *   The path to investigate for corresponding aliases or system URLs.
webmaster@1:  * @param $path_language
webmaster@1:  *   Optional language code to search the path with. Defaults to the page language.
webmaster@1:  *   If there's no path defined for that language it will search paths without
webmaster@1:  *   language.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   Either a Drupal system path, an aliased path, or FALSE if no path was
webmaster@1:  *   found.
webmaster@1:  */
webmaster@1: function drupal_lookup_path($action, $path = '', $path_language = '') {
webmaster@1:   global $language;
webmaster@1:   // $map is an array with language keys, holding arrays of Drupal paths to alias relations
webmaster@1:   static $map = array(), $no_src = array(), $count;
webmaster@1: 
webmaster@1:   $path_language = $path_language ? $path_language : $language->language;
webmaster@1: 
webmaster@1:   // Use $count to avoid looking up paths in subsequent calls if there simply are no aliases
webmaster@1:   if (!isset($count)) {
webmaster@1:     $count = db_result(db_query('SELECT COUNT(pid) FROM {url_alias}'));
webmaster@1:   }
webmaster@1: 
webmaster@1:   if ($action == 'wipe') {
webmaster@1:     $map = array();
webmaster@1:     $no_src = array();
webmaster@13:     $count = NULL;
webmaster@1:   }
webmaster@1:   elseif ($count > 0 && $path != '') {
webmaster@1:     if ($action == 'alias') {
webmaster@1:       if (isset($map[$path_language][$path])) {
webmaster@1:         return $map[$path_language][$path];
webmaster@1:       }
webmaster@1:       // Get the most fitting result falling back with alias without language
webmaster@1:       $alias = db_result(db_query("SELECT dst FROM {url_alias} WHERE src = '%s' AND language IN('%s', '') ORDER BY language DESC", $path, $path_language));
webmaster@1:       $map[$path_language][$path] = $alias;
webmaster@1:       return $alias;
webmaster@1:     }
webmaster@1:     // Check $no_src for this $path in case we've already determined that there
webmaster@1:     // isn't a path that has this alias
webmaster@1:     elseif ($action == 'source' && !isset($no_src[$path_language][$path])) {
webmaster@1:       // Look for the value $path within the cached $map
webmaster@1:       $src = '';
webmaster@1:       if (!isset($map[$path_language]) || !($src = array_search($path, $map[$path_language]))) {
webmaster@1:         // Get the most fitting result falling back with alias without language
webmaster@1:         if ($src = db_result(db_query("SELECT src FROM {url_alias} WHERE dst = '%s' AND language IN('%s', '') ORDER BY language DESC", $path, $path_language))) {
webmaster@1:           $map[$path_language][$src] = $path;
webmaster@1:         }
webmaster@1:         else {
webmaster@1:           // We can't record anything into $map because we do not have a valid
webmaster@1:           // index and there is no need because we have not learned anything
webmaster@1:           // about any Drupal path. Thus cache to $no_src.
webmaster@1:           $no_src[$path_language][$path] = TRUE;
webmaster@1:         }
webmaster@1:       }
webmaster@1:       return $src;
webmaster@1:     }
webmaster@1:   }
webmaster@1: 
webmaster@1:   return FALSE;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Given an internal Drupal path, return the alias set by the administrator.
webmaster@1:  *
webmaster@1:  * @param $path
webmaster@1:  *   An internal Drupal path.
webmaster@1:  * @param $path_language
webmaster@1:  *   An optional language code to look up the path in.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   An aliased path if one was found, or the original path if no alias was
webmaster@1:  *   found.
webmaster@1:  */
webmaster@1: function drupal_get_path_alias($path, $path_language = '') {
webmaster@1:   $result = $path;
webmaster@1:   if ($alias = drupal_lookup_path('alias', $path, $path_language)) {
webmaster@1:     $result = $alias;
webmaster@1:   }
webmaster@1:   return $result;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Given a path alias, return the internal path it represents.
webmaster@1:  *
webmaster@1:  * @param $path
webmaster@1:  *   A Drupal path alias.
webmaster@1:  * @param $path_language
webmaster@1:  *   An optional language code to look up the path in.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   The internal path represented by the alias, or the original alias if no
webmaster@1:  *   internal path was found.
webmaster@1:  */
webmaster@1: function drupal_get_normal_path($path, $path_language = '') {
webmaster@1:   $result = $path;
webmaster@1:   if ($src = drupal_lookup_path('source', $path, $path_language)) {
webmaster@1:     $result = $src;
webmaster@1:   }
webmaster@1:   if (function_exists('custom_url_rewrite_inbound')) {
webmaster@1:     // Modules may alter the inbound request path by reference.
webmaster@1:     custom_url_rewrite_inbound($result, $path, $path_language);
webmaster@1:   }
webmaster@1:   return $result;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Return a component of the current Drupal path.
webmaster@1:  *
webmaster@1:  * When viewing a page at the path "admin/content/types", for example, arg(0)
webmaster@1:  * would return "admin", arg(1) would return "content", and arg(2) would return
webmaster@1:  * "types".
webmaster@1:  *
webmaster@1:  * Avoid use of this function where possible, as resulting code is hard to read.
webmaster@1:  * Instead, attempt to use named arguments in menu callback functions. See the
webmaster@1:  * explanation in menu.inc for how to construct callbacks that take arguments.
webmaster@1:  *
webmaster@1:  * @param $index
webmaster@1:  *   The index of the component, where each component is separated by a '/'
webmaster@1:  *   (forward-slash), and where the first component has an index of 0 (zero).
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   The component specified by $index, or NULL if the specified component was
webmaster@1:  *   not found.
webmaster@1:  */
webmaster@1: function arg($index = NULL, $path = NULL) {
webmaster@1:   static $arguments;
webmaster@1: 
webmaster@1:   if (!isset($path)) {
webmaster@1:     $path = $_GET['q'];
webmaster@1:   }
webmaster@1:   if (!isset($arguments[$path])) {
webmaster@1:     $arguments[$path] = explode('/', $path);
webmaster@1:   }
webmaster@1:   if (!isset($index)) {
webmaster@1:     return $arguments[$path];
webmaster@1:   }
webmaster@1:   if (isset($arguments[$path][$index])) {
webmaster@1:     return $arguments[$path][$index];
webmaster@1:   }
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Get the title of the current page, for display on the page and in the title bar.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   The current page's title.
webmaster@1:  */
webmaster@1: function drupal_get_title() {
webmaster@1:   $title = drupal_set_title();
webmaster@1: 
webmaster@1:   // during a bootstrap, menu.inc is not included and thus we cannot provide a title
webmaster@1:   if (!isset($title) && function_exists('menu_get_active_title')) {
webmaster@1:     $title = check_plain(menu_get_active_title());
webmaster@1:   }
webmaster@1: 
webmaster@1:   return $title;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Set the title of the current page, for display on the page and in the title bar.
webmaster@1:  *
webmaster@1:  * @param $title
webmaster@1:  *   Optional string value to assign to the page title; or if set to NULL
webmaster@1:  *   (default), leaves the current title unchanged.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   The updated title of the current page.
webmaster@1:  */
webmaster@1: function drupal_set_title($title = NULL) {
webmaster@1:   static $stored_title;
webmaster@1: 
webmaster@1:   if (isset($title)) {
webmaster@1:     $stored_title = $title;
webmaster@1:   }
webmaster@1:   return $stored_title;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Check if the current page is the front page.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   Boolean value: TRUE if the current page is the front page; FALSE if otherwise.
webmaster@1:  */
webmaster@1: function drupal_is_front_page() {
webmaster@1:   // As drupal_init_path updates $_GET['q'] with the 'site_frontpage' path,
webmaster@1:   // we can check it against the 'site_frontpage' variable.
webmaster@1:   return $_GET['q'] == drupal_get_normal_path(variable_get('site_frontpage', 'node'));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Check if a path matches any pattern in a set of patterns.
webmaster@1:  *
webmaster@1:  * @param $path
webmaster@1:  *   The path to match.
webmaster@1:  * @param $patterns
webmaster@1:  *   String containing a set of patterns separated by \n, \r or \r\n.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   Boolean value: TRUE if the path matches a pattern, FALSE otherwise.
webmaster@1:  */
webmaster@1: function drupal_match_path($path, $patterns) {
webmaster@1:   static $regexps;
webmaster@1: 
webmaster@1:   if (!isset($regexps[$patterns])) {
webmaster@1:     $regexps[$patterns] = '/^('. preg_replace(array('/(\r\n?|\n)/', '/\\\\\*/', '/(^|\|)\\\\<front\\\\>($|\|)/'), array('|', '.*', '\1'. preg_quote(variable_get('site_frontpage', 'node'), '/') .'\2'), preg_quote($patterns, '/')) .')$/';
webmaster@1:   }
webmaster@1:   return preg_match($regexps[$patterns], $path);
webmaster@1: }