Merge branch 'master' of gitorious.org:statusnet/mainline

12 files changed, 984 insertions, 83 deletions

diff --git a/lib/common.php b/lib/common.php
index 8d2e6b420..064f6f73a 100644
--- a/lib/common.php
+++ b/lib/common.php
@@ -22,10 +22,10 @@ if (!defined('STATUSNET') && !defined('LACONICA')) { exit(1); }
 //exit with 200 response, if this is checking fancy from the installer
 if (isset($_REQUEST['p']) && $_REQUEST['p'] == 'check-fancy') {  exit; }
 
-define('STATUSNET_VERSION', '0.9.1');
+define('STATUSNET_VERSION', '0.9.2');
 define('LACONICA_VERSION', STATUSNET_VERSION); // compatibility
 
-define('STATUSNET_CODENAME', 'Everybody Hurts');
+define('STATUSNET_CODENAME', 'King of Birds');
 
 define('AVATAR_PROFILE_SIZE', 96);
 define('AVATAR_STREAM_SIZE', 48);
diff --git a/lib/default.php b/lib/default.php
index ffeab70b3..fa4ece10a 100644
--- a/lib/default.php
+++ b/lib/default.php
@@ -72,6 +72,7 @@ $default =
               'quote_identifiers' => false,
               'type' => 'mysql',
               'schemacheck' => 'runtime', // 'runtime' or 'script'
+              'annotate_queries' => false, // true to add caller comments to queries, eg /* POST Notice::saveNew */
               'log_queries' => false, // true to log all DB queries
               'log_slow_queries' => 0), // if set, log queries taking over N seconds
         'syslog' =>
@@ -87,6 +88,8 @@ $default =
               'stomp_username' => null,
               'stomp_password' => null,
               'stomp_persistent' => true, // keep items across queue server restart, if persistence is enabled
+              'stomp_transactions' => true, // use STOMP transactions to aid in detecting failures (supported by ActiveMQ, but not by all)
+              'stomp_acks' => true, // send acknowledgements after successful processing (supported by ActiveMQ, but not by all)
               'stomp_manual_failover' => true, // if multiple servers are listed, treat them as separate (enqueue on one randomly, listen on all)
               'monitor' => null, // URL to monitor ping endpoint (work in progress)
               'softlimit' => '90%', // total size or % of memory_limit at which to restart queue threads gracefully
diff --git a/lib/httpclient.php b/lib/httpclient.php
index 64a51353c..384626ae0 100644
--- a/lib/httpclient.php
+++ b/lib/httpclient.php
@@ -43,6 +43,9 @@ require_once 'HTTP/Request2/Response.php';
  *
  * This extends the HTTP_Request2_Response class with methods to get info
  * about any followed redirects.
+ * 
+ * Originally used the name 'HTTPResponse' to match earlier code, but
+ * this conflicts with a class in in the PECL HTTP extension.
  *
  * @category HTTP
  * @package StatusNet
@@ -51,7 +54,7 @@ require_once 'HTTP/Request2/Response.php';
  * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
  * @link http://status.net/
  */
-class HTTPResponse extends HTTP_Request2_Response
+class StatusNet_HTTPResponse extends HTTP_Request2_Response
 {
     function __construct(HTTP_Request2_Response $response, $url, $redirects=0)
     {
@@ -146,7 +149,7 @@ class HTTPClient extends HTTP_Request2
     /**
      * Convenience function to run a GET request.
      *
-     * @return HTTPResponse
+     * @return StatusNet_HTTPResponse
      * @throws HTTP_Request2_Exception
      */
     public function get($url, $headers=array())
@@ -157,7 +160,7 @@ class HTTPClient extends HTTP_Request2
     /**
      * Convenience function to run a HEAD request.
      *
-     * @return HTTPResponse
+     * @return StatusNet_HTTPResponse
      * @throws HTTP_Request2_Exception
      */
     public function head($url, $headers=array())
@@ -171,7 +174,7 @@ class HTTPClient extends HTTP_Request2
      * @param string $url
      * @param array $headers optional associative array of HTTP headers
      * @param array $data optional associative array or blob of form data to submit
-     * @return HTTPResponse
+     * @return StatusNet_HTTPResponse
      * @throws HTTP_Request2_Exception
      */
     public function post($url, $headers=array(), $data=array())
@@ -183,7 +186,7 @@ class HTTPClient extends HTTP_Request2
     }
 
     /**
-     * @return HTTPResponse
+     * @return StatusNet_HTTPResponse
      * @throws HTTP_Request2_Exception
      */
     protected function doRequest($url, $method, $headers)
@@ -217,12 +220,12 @@ class HTTPClient extends HTTP_Request2
     }
 
     /**
-     * Actually performs the HTTP request and returns an HTTPResponse object
-     * with response body and header info.
+     * Actually performs the HTTP request and returns a
+     * StatusNet_HTTPResponse object with response body and header info.
      *
      * Wraps around parent send() to add logging and redirection processing.
      *
-     * @return HTTPResponse
+     * @return StatusNet_HTTPResponse
      * @throw HTTP_Request2_Exception
      */
     public function send()
@@ -265,6 +268,6 @@ class HTTPClient extends HTTP_Request2
             }
             break;
         } while ($maxRedirs);
-        return new HTTPResponse($response, $this->getUrl(), $redirs);
+        return new StatusNet_HTTPResponse($response, $this->getUrl(), $redirs);
     }
 }
diff --git a/lib/installer.php b/lib/installer.php
new file mode 100644
index 000000000..589a19a66
--- /dev/null
+++ b/lib/installer.php
@@ -0,0 +1,576 @@
+<?php
+
+/**
+ * StatusNet - the distributed open-source microblogging tool
+ * Copyright (C) 2009, StatusNet, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category Installation
+ * @package  Installation
+ *
+ * @author   Adrian Lang <mail@adrianlang.de>
+ * @author   Brenda Wallace <shiny@cpan.org>
+ * @author   Brett Taylor <brett@webfroot.co.nz>
+ * @author   Brion Vibber <brion@pobox.com>
+ * @author   CiaranG <ciaran@ciarang.com>
+ * @author   Craig Andrews <candrews@integralblue.com>
+ * @author   Eric Helgeson <helfire@Erics-MBP.local>
+ * @author   Evan Prodromou <evan@status.net>
+ * @author   Robin Millette <millette@controlyourself.ca>
+ * @author   Sarven Capadisli <csarven@status.net>
+ * @author   Tom Adams <tom@holizz.com>
+ * @author   Zach Copley <zach@status.net>
+ * @license  GNU Affero General Public License http://www.gnu.org/licenses/
+ * @version  0.9.x
+ * @link     http://status.net
+ */
+
+abstract class Installer
+{
+    /** Web site info */
+    public $sitename, $server, $path, $fancy;
+    /** DB info */
+    public $host, $dbname, $dbtype, $username, $password, $db;
+    /** Administrator info */
+    public $adminNick, $adminPass, $adminEmail, $adminUpdates;
+    /** Should we skip writing the configuration file? */
+    public $skipConfig = false;
+
+    public static $dbModules = array(
+        'mysql' => array(
+            'name' => 'MySQL',
+            'check_module' => 'mysqli',
+            'installer' => 'mysql_db_installer',
+        ),
+        'pgsql' => array(
+            'name' => 'PostgreSQL',
+            'check_module' => 'pgsql',
+            'installer' => 'pgsql_db_installer',
+        ),
+    );
+
+    /**
+     * Attempt to include a PHP file and report if it worked, while
+     * suppressing the annoying warning messages on failure.
+     */
+    private function haveIncludeFile($filename) {
+        $old = error_reporting(error_reporting() & ~E_WARNING);
+        $ok = include_once($filename);
+        error_reporting($old);
+        return $ok;
+    }
+    
+    /**
+     * Check if all is ready for installation
+     *
+     * @return void
+     */
+    function checkPrereqs()
+    {
+        $pass = true;
+
+        if (file_exists(INSTALLDIR.'/config.php')) {
+            $this->warning('Config file "config.php" already exists.');
+            $pass = false;
+        }
+
+        if (version_compare(PHP_VERSION, '5.2.3', '<')) {
+            $errors[] = 'Require PHP version 5.2.3 or greater.';
+            $pass = false;
+        }
+
+        // Look for known library bugs
+        $str = "abcdefghijklmnopqrstuvwxyz";
+        $replaced = preg_replace('/[\p{Cc}\p{Cs}]/u', '*', $str);
+        if ($str != $replaced) {
+            $this->warning('PHP is linked to a version of the PCRE library ' .
+                           'that does not support Unicode properties. ' .
+                           'If you are running Red Hat Enterprise Linux / ' .
+                           'CentOS 5.4 or earlier, see <a href="' .
+                           'http://status.net/wiki/Red_Hat_Enterprise_Linux#PCRE_library' .
+                           '">our documentation page</a> on fixing this.');
+            $pass = false;
+        }
+
+        $reqs = array('gd', 'curl',
+                      'xmlwriter', 'mbstring', 'xml', 'dom', 'simplexml');
+
+        foreach ($reqs as $req) {
+            if (!$this->checkExtension($req)) {
+                $this->warning(sprintf('Cannot load required extension: <code>%s</code>', $req));
+                $pass = false;
+            }
+        }
+
+        // Make sure we have at least one database module available
+        $missingExtensions = array();
+        foreach (self::$dbModules as $type => $info) {
+            if (!$this->checkExtension($info['check_module'])) {
+                $missingExtensions[] = $info['check_module'];
+            }
+        }
+
+        if (count($missingExtensions) == count(self::$dbModules)) {
+            $req = implode(', ', $missingExtensions);
+            $this->warning(sprintf('Cannot find a database extension. You need at least one of %s.', $req));
+            $pass = false;
+        }
+
+        if (!is_writable(INSTALLDIR)) {
+            $this->warning(sprintf('Cannot write config file to: <code>%s</code></p>', INSTALLDIR),
+                           sprintf('On your server, try this command: <code>chmod a+w %s</code>', INSTALLDIR));
+            $pass = false;
+        }
+
+        // Check the subdirs used for file uploads
+        $fileSubdirs = array('avatar', 'background', 'file');
+        foreach ($fileSubdirs as $fileSubdir) {
+            $fileFullPath = INSTALLDIR."/$fileSubdir/";
+            if (!is_writable($fileFullPath)) {
+                $this->warning(sprintf('Cannot write to %s directory: <code>%s</code>', $fileSubdir, $fileFullPath),
+                               sprintf('On your server, try this command: <code>chmod a+w %s</code>', $fileFullPath));
+                $pass = false;
+            }
+        }
+
+        return $pass;
+    }
+
+    /**
+     * Checks if a php extension is both installed and loaded
+     *
+     * @param string $name of extension to check
+     *
+     * @return boolean whether extension is installed and loaded
+     */
+    function checkExtension($name)
+    {
+        if (extension_loaded($name)) {
+            return true;
+        } elseif (function_exists('dl') && ini_get('enable_dl') && !ini_get('safe_mode')) {
+            // dl will throw a fatal error if it's disabled or we're in safe mode.
+            // More fun, it may not even exist under some SAPIs in 5.3.0 or later...
+            $soname = $name . '.' . PHP_SHLIB_SUFFIX;
+            if (PHP_SHLIB_SUFFIX == 'dll') {
+                $soname = "php_" . $soname;
+            }
+            return @dl($soname);
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * Basic validation on the database paramters
+     * Side effects: error output if not valid
+     * 
+     * @return boolean success
+     */
+    function validateDb()
+    {
+        $fail = false;
+
+        if (empty($this->host)) {
+            $this->updateStatus("No hostname specified.", true);
+            $fail = true;
+        }
+
+        if (empty($this->database)) {
+            $this->updateStatus("No database specified.", true);
+            $fail = true;
+        }
+
+        if (empty($this->username)) {
+            $this->updateStatus("No username specified.", true);
+            $fail = true;
+        }
+
+        if (empty($this->sitename)) {
+            $this->updateStatus("No sitename specified.", true);
+            $fail = true;
+        }
+
+        return !$fail;
+    }
+
+    /**
+     * Basic validation on the administrator user paramters
+     * Side effects: error output if not valid
+     * 
+     * @return boolean success
+     */
+    function validateAdmin()
+    {
+        $fail = false;
+
+        if (empty($this->adminNick)) {
+            $this->updateStatus("No initial StatusNet user nickname specified.", true);
+            $fail = true;
+        }
+        if ($this->adminNick && !preg_match('/^[0-9a-z]{1,64}$/', $this->adminNick)) {
+            $this->updateStatus('The user nickname "' . htmlspecialchars($this->adminNick) .
+                         '" is invalid; should be plain letters and numbers no longer than 64 characters.', true);
+            $fail = true;
+        }
+        // @fixme hardcoded list; should use User::allowed_nickname()
+        // if/when it's safe to have loaded the infrastructure here
+        $blacklist = array('main', 'admin', 'twitter', 'settings', 'rsd.xml', 'favorited', 'featured', 'favoritedrss', 'featuredrss', 'rss', 'getfile', 'api', 'groups', 'group', 'peopletag', 'tag', 'user', 'message', 'conversation', 'bookmarklet', 'notice', 'attachment', 'search', 'index.php', 'doc', 'opensearch', 'robots.txt', 'xd_receiver.html', 'facebook');
+        if (in_array($this->adminNick, $blacklist)) {
+            $this->updateStatus('The user nickname "' . htmlspecialchars($this->adminNick) .
+                         '" is reserved.', true);
+            $fail = true;
+        }
+
+        if (empty($this->adminPass)) {
+            $this->updateStatus("No initial StatusNet user password specified.", true);
+            $fail = true;
+        }
+
+        return !$fail;
+    }
+
+    /**
+     * Set up the database with the appropriate function for the selected type...
+     * Saves database info into $this->db.
+     * 
+     * @return mixed array of database connection params on success, false on failure
+     */
+    function setupDatabase()
+    {
+        if ($this->db) {
+            throw new Exception("Bad order of operations: DB already set up.");
+        }
+        $method = self::$dbModules[$this->dbtype]['installer'];
+        $db = call_user_func(array($this, $method),
+                             $this->host,
+                             $this->database,
+                             $this->username,
+                             $this->password);
+        $this->db = $db;
+        return $this->db;
+    }
+
+    /**
+     * Set up a database on PostgreSQL.
+     * Will output status updates during the operation.
+     * 
+     * @param string $host
+     * @param string $database
+     * @param string $username
+     * @param string $password
+     * @return mixed array of database connection params on success, false on failure
+     * 
+     * @fixme escape things in the connection string in case we have a funny pass etc
+     */
+    function Pgsql_Db_installer($host, $database, $username, $password)
+    {
+        $connstring = "dbname=$database host=$host user=$username";
+
+        //No password would mean trust authentication used.
+        if (!empty($password)) {
+            $connstring .= " password=$password";
+        }
+        $this->updateStatus("Starting installation...");
+        $this->updateStatus("Checking database...");
+        $conn = pg_connect($connstring);
+
+        if ($conn ===false) {
+            $this->updateStatus("Failed to connect to database: $connstring");
+            return false;
+        }
+
+        //ensure database encoding is UTF8
+        $record = pg_fetch_object(pg_query($conn, 'SHOW server_encoding'));
+        if ($record->server_encoding != 'UTF8') {
+            $this->updateStatus("StatusNet requires UTF8 character encoding. Your database is ". htmlentities($record->server_encoding));
+            return false;
+        }
+
+        $this->updateStatus("Running database script...");
+        //wrap in transaction;
+        pg_query($conn, 'BEGIN');
+        $res = $this->runDbScript('statusnet_pg.sql', $conn, 'pgsql');
+
+        if ($res === false) {
+            $this->updateStatus("Can't run database script.", true);
+            return false;
+        }
+        foreach (array('sms_carrier' => 'SMS carrier',
+                    'notice_source' => 'notice source',
+                    'foreign_services' => 'foreign service')
+              as $scr => $name) {
+            $this->updateStatus(sprintf("Adding %s data to database...", $name));
+            $res = $this->runDbScript($scr.'.sql', $conn, 'pgsql');
+            if ($res === false) {
+                $this->updateStatus(sprintf("Can't run %d script.", $name), true);
+                return false;
+            }
+        }
+        pg_query($conn, 'COMMIT');
+
+        if (empty($password)) {
+            $sqlUrl = "pgsql://$username@$host/$database";
+        } else {
+            $sqlUrl = "pgsql://$username:$password@$host/$database";
+        }
+
+        $db = array('type' => 'pgsql', 'database' => $sqlUrl);
+
+        return $db;
+    }
+
+    /**
+     * Set up a database on MySQL.
+     * Will output status updates during the operation.
+     * 
+     * @param string $host
+     * @param string $database
+     * @param string $username
+     * @param string $password
+     * @return mixed array of database connection params on success, false on failure
+     * 
+     * @fixme escape things in the connection string in case we have a funny pass etc
+     */
+    function Mysql_Db_installer($host, $database, $username, $password)
+    {
+        $this->updateStatus("Starting installation...");
+        $this->updateStatus("Checking database...");
+
+        $conn = mysqli_init();
+        if (!$conn->real_connect($host, $username, $password)) {
+            $this->updateStatus("Can't connect to server '$host' as '$username'.", true);
+            return false;
+        }
+        $this->updateStatus("Changing to database...");
+        if (!$conn->select_db($database)) {
+            $this->updateStatus("Can't change to database.", true);
+            return false;
+        }
+
+        $this->updateStatus("Running database script...");
+        $res = $this->runDbScript('statusnet.sql', $conn);
+        if ($res === false) {
+            $this->updateStatus("Can't run database script.", true);
+            return false;
+        }
+        foreach (array('sms_carrier' => 'SMS carrier',
+                    'notice_source' => 'notice source',
+                    'foreign_services' => 'foreign service')
+              as $scr => $name) {
+            $this->updateStatus(sprintf("Adding %s data to database...", $name));
+            $res = $this->runDbScript($scr.'.sql', $conn);
+            if ($res === false) {
+                $this->updateStatus(sprintf("Can't run %d script.", $name), true);
+                return false;
+            }
+        }
+
+        $sqlUrl = "mysqli://$username:$password@$host/$database";
+        $db = array('type' => 'mysql', 'database' => $sqlUrl);
+        return $db;
+    }
+
+    /**
+     * Write a stock configuration file.
+     *
+     * @return boolean success
+     * 
+     * @fixme escape variables in output in case we have funny chars, apostrophes etc
+     */
+    function writeConf()
+    {
+        // assemble configuration file in a string
+        $cfg =  "<?php\n".
+                "if (!defined('STATUSNET') && !defined('LACONICA')) { exit(1); }\n\n".
+
+                // site name
+                "\$config['site']['name'] = '{$this->sitename}';\n\n".
+
+                // site location
+                "\$config['site']['server'] = '{$this->server}';\n".
+                "\$config['site']['path'] = '{$this->path}'; \n\n".
+
+                // checks if fancy URLs are enabled
+                ($this->fancy ? "\$config['site']['fancy'] = true;\n\n":'').
+
+                // database
+                "\$config['db']['database'] = '{$this->db['database']}';\n\n".
+                ($this->db['type'] == 'pgsql' ? "\$config['db']['quote_identifiers'] = true;\n\n":'').
+                "\$config['db']['type'] = '{$this->db['type']}';\n\n";
+        // write configuration file out to install directory
+        $res = file_put_contents(INSTALLDIR.'/config.php', $cfg);
+
+        return $res;
+    }
+
+    /**
+     * Install schema into the database
+     *
+     * @param string $filename location of database schema file
+     * @param dbconn $conn     connection to database
+     * @param string $type     type of database, currently mysql or pgsql
+     *
+     * @return boolean - indicating success or failure
+     */
+    function runDbScript($filename, $conn, $type = 'mysqli')
+    {
+        $sql = trim(file_get_contents(INSTALLDIR . '/db/' . $filename));
+        $stmts = explode(';', $sql);
+        foreach ($stmts as $stmt) {
+            $stmt = trim($stmt);
+            if (!mb_strlen($stmt)) {
+                continue;
+            }
+            // FIXME: use PEAR::DB or PDO instead of our own switch
+            switch ($type) {
+            case 'mysqli':
+                $res = $conn->query($stmt);
+                if ($res === false) {
+                    $error = $conn->error();
+                }
+                break;
+            case 'pgsql':
+                $res = pg_query($conn, $stmt);
+                if ($res === false) {
+                    $error = pg_last_error();
+                }
+                break;
+            default:
+                $this->updateStatus("runDbScript() error: unknown database type ". $type ." provided.");
+            }
+            if ($res === false) {
+                $this->updateStatus("ERROR ($error) for SQL '$stmt'");
+                return $res;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Create the initial admin user account.
+     * Side effect: may load portions of StatusNet framework.
+     * Side effect: outputs program info
+     */
+    function registerInitialUser()
+    {
+        define('STATUSNET', true);
+        define('LACONICA', true); // compatibility
+
+        require_once INSTALLDIR . '/lib/common.php';
+
+        $data = array('nickname' => $this->adminNick,
+                      'password' => $this->adminPass,
+                      'fullname' => $this->adminNick);
+        if ($this->adminEmail) {
+            $data['email'] = $this->adminEmail;
+        }
+        $user = User::register($data);
+
+        if (empty($user)) {
+            return false;
+        }
+
+        // give initial user carte blanche
+
+        $user->grantRole('owner');
+        $user->grantRole('moderator');
+        $user->grantRole('administrator');
+        
+        // Attempt to do a remote subscribe to update@status.net
+        // Will fail if instance is on a private network.
+
+        if ($this->adminUpdates && class_exists('Ostatus_profile')) {
+            try {
+                $oprofile = Ostatus_profile::ensureProfileURL('http://update.status.net/');
+                Subscription::start($user->getProfile(), $oprofile->localProfile());
+                $this->updateStatus("Set up subscription to <a href='http://update.status.net/'>update@status.net</a>.");
+            } catch (Exception $e) {
+                $this->updateStatus("Could not set up subscription to <a href='http://update.status.net/'>update@status.net</a>.", true);
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * The beef of the installer!
+     * Create database, config file, and admin user.
+     * 
+     * Prerequisites: validation of input data.
+     * 
+     * @return boolean success
+     */
+    function doInstall()
+    {
+        $this->db = $this->setupDatabase();
+
+        if (!$this->db) {
+            // database connection failed, do not move on to create config file.
+            return false;
+        }
+
+        if (!$this->skipConfig) {
+            $this->updateStatus("Writing config file...");
+            $res = $this->writeConf();
+
+            if (!$res) {
+                $this->updateStatus("Can't write config file.", true);
+                return false;
+            }
+        }
+
+        if (!empty($this->adminNick)) {
+            // Okay, cross fingers and try to register an initial user
+            if ($this->registerInitialUser()) {
+                $this->updateStatus(
+                    "An initial user with the administrator role has been created."
+                );
+            } else {
+                $this->updateStatus(
+                    "Could not create initial StatusNet user (administrator).",
+                    true
+                );
+                return false;
+            }
+        }
+
+        /*
+            TODO https needs to be considered
+        */
+        $link = "http://".$this->server.'/'.$this->path;
+
+        $this->updateStatus("StatusNet has been installed at $link");
+        $this->updateStatus(
+            "<strong>DONE!</strong> You can visit your <a href='$link'>new StatusNet site</a> (login as '$this->adminNick'). If this is your first StatusNet install, you may want to poke around our <a href='http://status.net/wiki/Getting_started'>Getting Started guide</a>."
+        );
+
+        return true;
+    }
+
+    /**
+     * Output a pre-install-time warning message
+     * @param string $message HTML ok, but should be plaintext-able
+     * @param string $submessage HTML ok, but should be plaintext-able
+     */
+    abstract function warning($message, $submessage='');
+
+    /**
+     * Output an install-time progress message
+     * @param string $message HTML ok, but should be plaintext-able
+     * @param boolean $error true if this should be marked as an error condition
+     */
+    abstract function updateStatus($status, $error=false);
+
+}
diff --git a/lib/jabber.php b/lib/jabber.php
index db4e2e9a7..cdcfc4423 100644
--- a/lib/jabber.php
+++ b/lib/jabber.php
@@ -34,39 +34,198 @@ if (!defined('STATUSNET') && !defined('LACONICA')) {
 require_once 'XMPPHP/XMPP.php';
 
 /**
- * checks whether a string is a syntactically valid Jabber ID (JID)
+ * Splits a Jabber ID (JID) into node, domain, and resource portions.
+ * 
+ * Based on validation routine submitted by:
+ * @copyright 2009 Patrick Georgi <patrick@georgi-clan.de>
+ * @license Licensed under ISC-L, which is compatible with everything else that keeps the copyright notice intact. 
  *
  * @param string $jid string to check
  *
+ * @return array with "node", "domain", and "resource" indices
+ * @throws Exception if input is not valid
+ */
+
+function jabber_split_jid($jid)
+{
+    $chars = '';
+    /* the following definitions come from stringprep, Appendix C,
+       which is used in its entirety by nodeprop, Chapter 5, "Prohibited Output" */
+    /* C1.1 ASCII space characters */
+    $chars .= "\x{20}";
+    /* C1.2 Non-ASCII space characters */
+    $chars .= "\x{a0}\x{1680}\x{2000}-\x{200b}\x{202f}\x{205f}\x{3000a}";
+    /* C2.1 ASCII control characters */
+    $chars .= "\x{00}-\x{1f}\x{7f}";
+    /* C2.2 Non-ASCII control characters */
+    $chars .= "\x{80}-\x{9f}\x{6dd}\x{70f}\x{180e}\x{200c}\x{200d}\x{2028}\x{2029}\x{2060}-\x{2063}\x{206a}-\x{206f}\x{feff}\x{fff9}-\x{fffc}\x{1d173}-\x{1d17a}";
+    /* C3 - Private Use */
+    $chars .= "\x{e000}-\x{f8ff}\x{f0000}-\x{ffffd}\x{100000}-\x{10fffd}";
+    /* C4 - Non-character code points */
+    $chars .= "\x{fdd0}-\x{fdef}\x{fffe}\x{ffff}\x{1fffe}\x{1ffff}\x{2fffe}\x{2ffff}\x{3fffe}\x{3ffff}\x{4fffe}\x{4ffff}\x{5fffe}\x{5ffff}\x{6fffe}\x{6ffff}\x{7fffe}\x{7ffff}\x{8fffe}\x{8ffff}\x{9fffe}\x{9ffff}\x{afffe}\x{affff}\x{bfffe}\x{bffff}\x{cfffe}\x{cffff}\x{dfffe}\x{dffff}\x{efffe}\x{effff}\x{ffffe}\x{fffff}\x{10fffe}\x{10ffff}";
+    /* C5 - Surrogate codes */
+    $chars .= "\x{d800}-\x{dfff}";
+    /* C6 - Inappropriate for plain text */
+    $chars .= "\x{fff9}-\x{fffd}";
+    /* C7 - Inappropriate for canonical representation */
+    $chars .= "\x{2ff0}-\x{2ffb}";
+    /* C8 - Change display properties or are deprecated */
+    $chars .= "\x{340}\x{341}\x{200e}\x{200f}\x{202a}-\x{202e}\x{206a}-\x{206f}";
+    /* C9 - Tagging characters */
+    $chars .= "\x{e0001}\x{e0020}-\x{e007f}";
+
+    /* Nodeprep forbids some more characters */
+    $nodeprepchars = $chars;
+    $nodeprepchars .= "\x{22}\x{26}\x{27}\x{2f}\x{3a}\x{3c}\x{3e}\x{40}";
+
+    $parts = explode("/", $jid, 2);
+    if (count($parts) > 1) {
+        $resource = $parts[1];
+        if ($resource == '') {
+            // Warning: empty resource isn't legit.
+            // But if we're normalizing, we may as well take it...
+        }
+    } else {
+        $resource = null;
+    }
+
+    $node = explode("@", $parts[0]);
+    if ((count($node) > 2) || (count($node) == 0)) {
+        throw new Exception("Invalid JID: too many @s");
+    } else if (count($node) == 1) {
+        $domain = $node[0];
+        $node = null;
+    } else {
+        $domain = $node[1];
+        $node = $node[0];
+        if ($node == '') {
+            throw new Exception("Invalid JID: @ but no node");
+        }
+    }
+
+    // Length limits per http://xmpp.org/rfcs/rfc3920.html#addressing
+    if ($node !== null) {
+        if (strlen($node) > 1023) {
+            throw new Exception("Invalid JID: node too long.");
+        }
+        if (preg_match("/[".$nodeprepchars."]/u", $node)) {
+            throw new Exception("Invalid JID node '$node'");
+        }
+    }
+
+    if (strlen($domain) > 1023) {
+        throw new Exception("Invalid JID: domain too long.");
+    }
+    if (!common_valid_domain($domain)) {
+        throw new Exception("Invalid JID domain name '$domain'");
+    }
+
+    if ($resource !== null) {
+        if (strlen($resource) > 1023) {
+            throw new Exception("Invalid JID: resource too long.");
+        }
+        if (preg_match("/[".$chars."]/u", $resource)) {
+            throw new Exception("Invalid JID resource '$resource'");
+        }
+    }
+
+    return array('node' => is_null($node) ? null : mb_strtolower($node),
+                 'domain' => is_null($domain) ? null : mb_strtolower($domain),
+                 'resource' => $resource);
+}
+
+/**
+ * Checks whether a string is a syntactically valid Jabber ID (JID),
+ * either with or without a resource.
+ * 
+ * Note that a bare domain can be a valid JID.
+ * 
+ * @param string $jid string to check
+ * @param bool $check_domain whether we should validate that domain...
+ *
  * @return     boolean whether the string is a valid JID
  */
+function jabber_valid_full_jid($jid, $check_domain=false)
+{
+    try {
+        $parts = jabber_split_jid($jid);
+        if ($check_domain) {
+            if (!jabber_check_domain($parts['domain'])) {
+                return false;
+            }
+        }
+        return $parts['resource'] !== ''; // missing or present; empty ain't kosher
+    } catch (Exception $e) {
+        return false;
+    }
+}
 
-function jabber_valid_base_jid($jid)
+/**
+ * Checks whether a string is a syntactically valid base Jabber ID (JID).
+ * A base JID won't include a resource specifier on the end; since we
+ * take it off when reading input we can't really use them reliably
+ * to direct outgoing messages yet (sorry guys!)
+ * 
+ * Note that a bare domain can be a valid JID.
+ * 
+ * @param string $jid string to check
+ * @param bool $check_domain whether we should validate that domain...
+ *
+ * @return     boolean whether the string is a valid JID
+ */
+function jabber_valid_base_jid($jid, $check_domain=false)
 {
-    // Cheap but effective
-    return Validate::email($jid);
+    try {
+        $parts = jabber_split_jid($jid);
+        if ($check_domain) {
+            if (!jabber_check_domain($parts['domain'])) {
+                return false;
+            }
+        }
+        return ($parts['resource'] === null); // missing; empty ain't kosher
+    } catch (Exception $e) {
+        return false;
+    }
 }
 
 /**
- * normalizes a Jabber ID for comparison
+ * Normalizes a Jabber ID for comparison, dropping the resource component if any.
  *
  * @param string $jid JID to check
+ * @param bool $check_domain if true, reject if the domain isn't findable
  *
  * @return string an equivalent JID in normalized (lowercase) form
  */
 
 function jabber_normalize_jid($jid)
 {
-    if (preg_match("/(?:([^\@]+)\@)?([^\/]+)(?:\/(.*))?$/", $jid, $matches)) {
-        $node   = $matches[1];
-        $server = $matches[2];
-        return strtolower($node.'@'.$server);
-    } else {
+    try {
+        $parts = jabber_split_jid($jid);
+        if ($parts['node'] !== null) {
+            return $parts['node'] . '@' . $parts['domain'];
+        } else {
+            return $parts['domain'];
+        }
+    } catch (Exception $e) {
         return null;
     }
 }
 
 /**
+ * Check if this domain's got some legit DNS record
+ */
+function jabber_check_domain($domain)
+{
+    if (checkdnsrr("_xmpp-server._tcp." . $domain, "SRV")) {
+        return true;
+    }
+    if (checkdnsrr($domain, "ANY")) {
+        return true;
+    }
+    return false;
+}
+
+/**
  * the JID of the Jabber daemon for this StatusNet instance
  *
  * @return string JID of the Jabber daemon
diff --git a/lib/mail.php b/lib/mail.php
index d73603694..5fc584e28 100644
--- a/lib/mail.php
+++ b/lib/mail.php
@@ -170,8 +170,10 @@ function mail_to_user(&$user, $subject, $body, $headers=array(), $address=null)
 
 function mail_confirm_address($user, $code, $nickname, $address)
 {
+    // TRANS: Subject for address confirmation email
     $subject = _('Email address confirmation');
 
+    // TRANS: Body for address confirmation email.
     $body = sprintf(_("Hey, %s.\n\n".
                       "Someone just entered this email address on %s.\n\n" .
                       "If it was you, and you want to confirm your entry, ".
@@ -237,11 +239,13 @@ function mail_subscribe_notify_profile($listenee, $other)
         $headers = _mail_prepare_headers('subscribe', $listenee->nickname, $other->nickname);
         $headers['From']    = mail_notify_from();
         $headers['To']      = $name . ' <' . $listenee->email . '>';
+        // TRANS: Subject of new-subscriber notification e-mail
         $headers['Subject'] = sprintf(_('%1$s is now listening to '.
                                         'your notices on %2$s.'),
                                       $other->getBestName(),
                                       common_config('site', 'name'));
 
+        // TRANS: Main body of new-subscriber notification e-mail
         $body = sprintf(_('%1$s is now listening to your notices on %2$s.'."\n\n".
                           "\t".'%3$s'."\n\n".
                           '%4$s'.
@@ -255,10 +259,13 @@ function mail_subscribe_notify_profile($listenee, $other)
                         common_config('site', 'name'),
                         $other->profileurl,
                         ($other->location) ?
+                        // TRANS: Profile info line in new-subscriber notification e-mail
                         sprintf(_("Location: %s"), $other->location) . "\n" : '',
                         ($other->homepage) ?
+                        // TRANS: Profile info line in new-subscriber notification e-mail
                         sprintf(_("Homepage: %s"), $other->homepage) . "\n" : '',
                         ($other->bio) ?
+                        // TRANS: Profile info line in new-subscriber notification e-mail
                         sprintf(_("Bio: %s"), $other->bio) . "\n\n" : '',
                         common_config('site', 'name'),
                         common_local_url('emailsettings'));
@@ -287,9 +294,11 @@ function mail_new_incoming_notify($user)
 
     $headers['From']    = $user->incomingemail;
     $headers['To']      = $name . ' <' . $user->email . '>';
+    // TRANS: Subject of notification mail for new posting email address
     $headers['Subject'] = sprintf(_('New email address for posting to %s'),
                                   common_config('site', 'name'));
 
+    // TRANS: Body of notification mail for new posting email address
     $body = sprintf(_("You have a new posting address on %1\$s.\n\n".
                       "Send email to %2\$s to post new messages.\n\n".
                       "More email instructions at %3\$s.\n\n".
@@ -414,6 +423,7 @@ function mail_send_sms_notice_address($notice, $smsemail, $incomingemail)
 
     $headers['From']    = ($incomingemail) ? $incomingemail : mail_notify_from();
     $headers['To']      = $to;
+    // TRANS: Subject line for SMS-by-email notification messages
     $headers['Subject'] = sprintf(_('%s status'),
                                   $other->getBestName());
 
@@ -440,11 +450,11 @@ function mail_confirm_sms($code, $nickname, $address)
 
     $headers['From']    = mail_notify_from();
     $headers['To']      = $nickname . ' <' . $address . '>';
+    // TRANS: Subject line for SMS-by-email address confirmation message
     $headers['Subject'] = _('SMS confirmation');
 
-    // FIXME: I18N
-
-    $body  = "$nickname: confirm you own this phone number with this code:";
+    // TRANS: Main body heading for SMS-by-email address confirmation message
+    $body  = sprintf(_("%s: confirm you own this phone number with this code:"), $nickname);
     $body .= "\n\n";
     $body .= $code;
     $body .= "\n\n";
@@ -464,10 +474,12 @@ function mail_confirm_sms($code, $nickname, $address)
 function mail_notify_nudge($from, $to)
 {
     common_init_locale($to->language);
+    // TRANS: Subject for 'nudge' notification email
     $subject = sprintf(_('You\'ve been nudged by %s'), $from->nickname);
 
     $from_profile = $from->getProfile();
 
+    // TRANS: Body for 'nudge' notification email
     $body = sprintf(_("%1\$s (%2\$s) is wondering what you are up to ".
                       "these days and is inviting you to post some news.\n\n".
                       "So let's hear from you :)\n\n".
@@ -514,10 +526,12 @@ function mail_notify_message($message, $from=null, $to=null)
     }
 
     common_init_locale($to->language);
+    // TRANS: Subject for direct-message notification email
     $subject = sprintf(_('New private message from %s'), $from->nickname);
 
     $from_profile = $from->getProfile();
 
+    // TRANS: Body for direct-message notification email
     $body = sprintf(_("%1\$s (%2\$s) sent you a private message:\n\n".
                       "------------------------------------------------------\n".
                       "%3\$s\n".
@@ -565,8 +579,10 @@ function mail_notify_fave($other, $user, $notice)
 
     common_init_locale($other->language);
 
+    // TRANS: Subject for favorite notification email
     $subject = sprintf(_('%s (@%s) added your notice as a favorite'), $bestname, $user->nickname);
 
+    // TRANS: Body for favorite notification email
     $body = sprintf(_("%1\$s (@%7\$s) just added your notice from %2\$s".
                       " as one of their favorites.\n\n" .
                       "The URL of your notice is:\n\n" .
@@ -622,24 +638,25 @@ function mail_notify_attn($user, $notice)
 
     common_switch_locale($user->language);
 
-        if ($notice->conversation != $notice->id) {
-                $conversationEmailText = "The full conversation can be read here:\n\n".
-                                                                 "\t%5\$s\n\n ";
-                $conversationUrl            = common_local_url('conversation',
-                                 array('id' => $notice->conversation)).'#notice-'.$notice->id;
-        } else {
-                $conversationEmailText = "%5\$s";
-                $conversationUrl = null;
-        }
+    if ($notice->hasConversation()) {
+        $conversationUrl = common_local_url('conversation',
+                         array('id' => $notice->conversation)).'#notice-'.$notice->id;
+        // TRANS: Line in @-reply notification e-mail. %s is conversation URL.
+        $conversationEmailText = sprintf(_("The full conversation can be read here:\n\n".
+                                           "\t%s"), $conversationUrl) . "\n\n";
+    } else {
+        $conversationEmailText = '';
+    }
 
     $subject = sprintf(_('%s (@%s) sent a notice to your attention'), $bestname, $sender->nickname);
 
+        // TRANS: Body of @-reply notification e-mail.
         $body = sprintf(_("%1\$s (@%9\$s) just sent a notice to your attention (an '@-reply') on %2\$s.\n\n".
                       "The notice is here:\n\n".
                       "\t%3\$s\n\n" .
                       "It reads:\n\n".
                       "\t%4\$s\n\n" .
-                      $conversationEmailText .
+                      "%5\$s" .
                       "You can reply back here:\n\n".
                       "\t%6\$s\n\n" .
                       "The list of all @-replies for you here:\n\n" .
@@ -652,7 +669,7 @@ function mail_notify_attn($user, $notice)
                     common_local_url('shownotice',
                                      array('notice' => $notice->id)),//%3
                     $notice->content,//%4
-                                        $conversationUrl,//%5
+                    $conversationEmailText,//%5
                     common_local_url('newnotice',
                                      array('replyto' => $sender->nickname, 'inreplyto' => $notice->id)),//%6
                     common_local_url('replies',
diff --git a/lib/noticelist.php b/lib/noticelist.php
index 83c8de9f6..4f997a328 100644
--- a/lib/noticelist.php
+++ b/lib/noticelist.php
@@ -543,18 +543,7 @@ class NoticeListItem extends Widget
 
     function showContext()
     {
-        $hasConversation = false;
-        if (!empty($this->notice->conversation)) {
-            $conversation = Notice::conversationStream(
-                $this->notice->conversation,
-                1,
-                1
-            );
-            if ($conversation->N > 0) {
-                $hasConversation = true;
-            }
-        }
-        if ($hasConversation) {
+        if ($this->notice->hasConversation()) {
             $conv = Conversation::staticGet(
                 'id',
                 $this->notice->conversation
diff --git a/lib/plugin.php b/lib/plugin.php
index 65ccdafbb..f63bdf309 100644
--- a/lib/plugin.php
+++ b/lib/plugin.php
@@ -91,6 +91,7 @@ class Plugin
             $path = INSTALLDIR . "/plugins/$name/locale";
             if (file_exists($path) && is_dir($path)) {
                 bindtextdomain($name, $path);
+                bind_textdomain_codeset($name, 'UTF-8');
             }
         }
     }
diff --git a/lib/profileformaction.php b/lib/profileformaction.php
index 8a934666e..0ffafe5fb 100644
--- a/lib/profileformaction.php
+++ b/lib/profileformaction.php
@@ -41,7 +41,7 @@ if (!defined('STATUSNET') && !defined('LACONICA')) {
  * @link     http://status.net/
  */
 
-class ProfileFormAction extends Action
+class ProfileFormAction extends RedirectingAction
 {
     var $profile = null;
 
@@ -102,29 +102,6 @@ class ProfileFormAction extends Action
     }
 
     /**
-     * Return to the calling page based on hidden arguments
-     *
-     * @return void
-     */
-
-    function returnToArgs()
-    {
-        foreach ($this->args as $k => $v) {
-            if ($k == 'returnto-action') {
-                $action = $v;
-            } else if (substr($k, 0, 9) == 'returnto-') {
-                $args[substr($k, 9)] = $v;
-            }
-        }
-
-        if ($action) {
-            common_redirect(common_local_url($action, $args), 303);
-        } else {
-            $this->clientError(_("No return-to arguments."));
-        }
-    }
-
-    /**
      * handle a POST request
      *
      * sub-classes should overload this request
diff --git a/lib/redirectingaction.php b/lib/redirectingaction.php
new file mode 100644
index 000000000..f11585274
--- /dev/null
+++ b/lib/redirectingaction.php
@@ -0,0 +1,96 @@
+<?php
+/**
+ * Superclass for actions that redirect to a given return-to page on completion.
+ *
+ * PHP version 5
+ *
+ * StatusNet - the distributed open-source microblogging tool
+ * Copyright (C) 2009-2010, StatusNet, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category Action
+ * @package  StatusNet
+ * @author   Evan Prodromou <evan@status.net>
+ * @author   Brion Vibber <brion@status.net>
+ * @license  http://www.fsf.org/licensing/licenses/agpl.html AGPLv3
+ * @link     http://status.net/
+ */
+
+if (!defined('STATUSNET') && !defined('LACONICA')) {
+    exit(1);
+}
+
+/**
+ * Superclass for actions that redirect to a given return-to page on completion.
+ *
+ * @category Action
+ * @package  StatusNet
+ * @author   Evan Prodromou <evan@status.net>
+ * @author   Brion Vibber <brion@status.net>
+ * @license  http://www.fsf.org/licensing/licenses/agpl.html AGPLv3
+ * @link     http://status.net/
+ */
+
+
+class RedirectingAction extends Action
+{
+
+    /**
+     * Redirect browser to the page our hidden parameters requested,
+     * or if none given, to the url given by $this->defaultReturnTo().
+     * 
+     * To be called only after successful processing.
+     * 
+     * @fixme rename this -- it obscures Action::returnToArgs() which
+     * returns a list of arguments, and is a bit confusing.
+     * 
+     * @return void
+     */
+    function returnToArgs()
+    {
+        // Now, gotta figure where we go back to
+        $action = false;
+        $args = array();
+        $params = array();
+        foreach ($this->args as $k => $v) {
+            if ($k == 'returnto-action') {
+                $action = $v;
+            } else if (substr($k, 0, 15) == 'returnto-param-') {
+                $params[substr($k, 15)] = $v;
+            } elseif (substr($k, 0, 9) == 'returnto-') {
+                $args[substr($k, 9)] = $v;
+            }
+        }
+
+        if ($action) {
+            common_redirect(common_local_url($action, $args, $params), 303);
+        } else {
+            $url = $this->defaultReturnToUrl();
+        }
+        common_redirect($url, 303);
+    }
+
+    /**
+     * If we reached this form without returnto arguments, where should
+     * we go? May be overridden by subclasses to a reasonable destination
+     * for that action; default implementation throws an exception.
+     * 
+     * @return string URL
+     */
+    function defaultReturnTo()
+    {
+        $this->clientError(_("No return-to arguments."));
+    }
+}
diff --git a/lib/stompqueuemanager.php b/lib/stompqueuemanager.php
index 9af8b2f48..5d5c7ccfb 100644
--- a/lib/stompqueuemanager.php
+++ b/lib/stompqueuemanager.php
@@ -39,7 +39,8 @@ class StompQueueManager extends QueueManager
     protected $base;
     protected $control;
 
-    protected $useTransactions = true;
+    protected $useTransactions;
+    protected $useAcks;
 
     protected $sites = array();
     protected $subscriptions = array();
@@ -59,11 +60,13 @@ class StompQueueManager extends QueueManager
         } else {
             $this->servers = array($server);
         }
-        $this->username = common_config('queue', 'stomp_username');
-        $this->password = common_config('queue', 'stomp_password');
-        $this->base     = common_config('queue', 'queue_basename');
-        $this->control  = common_config('queue', 'control_channel');
-        $this->breakout = common_config('queue', 'breakout');
+        $this->username        = common_config('queue', 'stomp_username');
+        $this->password        = common_config('queue', 'stomp_password');
+        $this->base            = common_config('queue', 'queue_basename');
+        $this->control         = common_config('queue', 'control_channel');
+        $this->breakout        = common_config('queue', 'breakout');
+        $this->useTransactions = common_config('queue', 'stomp_transactions');
+        $this->useAcks         = common_config('queue', 'stomp_acks');
     }
 
     /**
@@ -703,13 +706,15 @@ class StompQueueManager extends QueueManager
 
     protected function ack($idx, $frame)
     {
-        if ($this->useTransactions) {
-            if (empty($this->transaction[$idx])) {
-                throw new Exception("Tried to ack but not in a transaction");
+        if ($this->useAcks) {
+            if ($this->useTransactions) {
+                if (empty($this->transaction[$idx])) {
+                    throw new Exception("Tried to ack but not in a transaction");
+                }
+                $this->cons[$idx]->ack($frame, $this->transaction[$idx]);
+            } else {
+                $this->cons[$idx]->ack($frame);
             }
-            $this->cons[$idx]->ack($frame, $this->transaction[$idx]);
-        } else {
-            $this->cons[$idx]->ack($frame);
         }
     }
 
diff --git a/lib/util.php b/lib/util.php
index 58d54cda3..c0013bb3d 100644
--- a/lib/util.php
+++ b/lib/util.php
@@ -1308,12 +1308,38 @@ function common_mtrand($bytes)
     return $enc;
 }
 
+/**
+ * Record the given URL as the return destination for a future
+ * form submission, to be read by common_get_returnto().
+ * 
+ * @param string $url
+ * 
+ * @fixme as a session-global setting, this can allow multiple forms
+ * to conflict and overwrite each others' returnto destinations if
+ * the user has multiple tabs or windows open.
+ * 
+ * Should refactor to index with a token or otherwise only pass the
+ * data along its intended path.
+ */
 function common_set_returnto($url)
 {
     common_ensure_session();
     $_SESSION['returnto'] = $url;
 }
 
+/**
+ * Fetch a return-destination URL previously recorded by
+ * common_set_returnto().
+ * 
+ * @return mixed URL string or null
+ * 
+ * @fixme as a session-global setting, this can allow multiple forms
+ * to conflict and overwrite each others' returnto destinations if
+ * the user has multiple tabs or windows open.
+ * 
+ * Should refactor to index with a token or otherwise only pass the
+ * data along its intended path.
+ */
 function common_get_returnto()
 {
     common_ensure_session();
@@ -1433,6 +1459,55 @@ function common_valid_tag($tag)
     return false;
 }
 
+/**
+ * Determine if given domain or address literal is valid
+ * eg for use in JIDs and URLs. Does not check if the domain
+ * exists!
+ * 
+ * @param string $domain
+ * @return boolean valid or not
+ */
+function common_valid_domain($domain)
+{
+    $octet = "(?:25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])";
+    $ipv4 = "(?:$octet(?:\.$octet){3})";
+    if (preg_match("/^$ipv4$/u", $domain)) return true;
+
+    $group = "(?:[0-9a-f]{1,4})";
+    $ipv6 = "(?:\[($group(?::$group){0,7})?(::)?($group(?::$group){0,7})?\])"; // http://tools.ietf.org/html/rfc3513#section-2.2
+
+    if (preg_match("/^$ipv6$/ui", $domain, $matches)) {
+        $before = explode(":", $matches[1]);
+        $zeroes = $matches[2];
+        $after = explode(":", $matches[3]);
+        if ($zeroes) {
+            $min = 0;
+            $max = 7;
+        } else {
+            $min = 1;
+            $max = 8;
+        }
+        $explicit = count($before) + count($after);
+        if ($explicit < $min || $explicit > $max) {
+            return false;
+        }
+        return true;
+    }
+
+    try {
+        require_once "Net/IDNA.php";
+        $idn = Net_IDNA::getInstance();
+        $domain = $idn->encode($domain);
+    } catch (Exception $e) {
+        return false;
+    }
+
+    $subdomain = "(?:[a-z0-9][a-z0-9-]*)"; // @fixme
+    $fqdn = "(?:$subdomain(?:\.$subdomain)*\.?)";
+
+    return preg_match("/^$fqdn$/ui", $domain);
+}
+
 /* Following functions are copied from MediaWiki GlobalFunctions.php
  * and written by Evan Prodromou. */