<?php

/**

 * @file

 * Provides API for defining and handling XML-RPC requests.

 */

/**

 * Invokes XML-RPC methods on this server.

 *

 * @param array $callbacks

 *   Either an associative array of external XML-RPC method names as keys with

 *   the callbacks they map to as values, or a more complex structure

 *   describing XML-RPC callbacks as returned from hook_xmlrpc().

 */

function xmlrpc_server($callbacks) {

  $xmlrpc_server = new stdClass();

  // Define built-in XML-RPC method names

  $defaults = array(

    'system.multicall' => 'xmlrpc_server_multicall',

    array(

      'system.methodSignature',

      'xmlrpc_server_method_signature',

      array('array', 'string'),

      'Returns an array describing the return type and required parameters of a method.',

    ),

    array(

      'system.getCapabilities',

      'xmlrpc_server_get_capabilities',

      array('struct'),

      'Returns a struct describing the XML-RPC specifications supported by this server.',

    ),

    array(

      'system.listMethods',

      'xmlrpc_server_list_methods',

      array('array'),

      'Returns an array of available methods on this server.',

    ),

    array(

      'system.methodHelp',

      'xmlrpc_server_method_help',

      array('string', 'string'),

      'Returns a documentation string for the specified method.',

    ),

  );

  // We build an array of all method names by combining the built-ins

  // with those defined by modules implementing the _xmlrpc hook.

  // Built-in methods are overridable.

  $callbacks = array_merge($defaults, (array) $callbacks);

  drupal_alter('xmlrpc', $callbacks);

  foreach ($callbacks as $key => $callback) {

    // we could check for is_array($callback)

    if (is_int($key)) {

      $method = $callback[0];

      $xmlrpc_server->callbacks[$method] = $callback[1];

      $xmlrpc_server->signatures[$method] = $callback[2];

      $xmlrpc_server->help[$method] = $callback[3];

    }

    else {

      $xmlrpc_server->callbacks[$key] = $callback;

      $xmlrpc_server->signatures[$key] = '';

      $xmlrpc_server->help[$key] = '';

    }

  }

  $data = file_get_contents('php://input');

  if (!$data) {

    print 'XML-RPC server accepts POST requests only.';

    drupal_exit();

  }

  $xmlrpc_server->message = xmlrpc_message($data);

  if (!xmlrpc_message_parse($xmlrpc_server->message)) {

    xmlrpc_server_error(-32700, t('Parse error. Request not well formed.'));

  }

  if ($xmlrpc_server->message->messagetype != 'methodCall') {

    xmlrpc_server_error(-32600, t('Server error. Invalid XML-RPC. Request must be a methodCall.'));

  }

  if (!isset($xmlrpc_server->message->params)) {

    $xmlrpc_server->message->params = array();

  }

  xmlrpc_server_set($xmlrpc_server);

  $result = xmlrpc_server_call($xmlrpc_server, $xmlrpc_server->message->methodname, $xmlrpc_server->message->params);

  if (is_object($result) && !empty($result->is_error)) {

    xmlrpc_server_error($result);

  }

  // Encode the result

  $r = xmlrpc_value($result);

  // Create the XML

  $xml = '

<methodResponse>

  <params>

  <param>

    <value>' . xmlrpc_value_get_xml($r) . '</value>

  </param>

  </params>

</methodResponse>

';

  // Send it

  xmlrpc_server_output($xml);

}

/**

 * Throws an XML-RPC error.

 *

 * @param $error

 *   An error object or integer error code.

 * @param $message

 *   (optional) The description of the error. Used only if an integer error

 *   code was passed in.

 */

function xmlrpc_server_error($error, $message = FALSE) {

  if ($message && !is_object($error)) {

    $error = xmlrpc_error($error, $message);

  }

  xmlrpc_server_output(xmlrpc_error_get_xml($error));

}

/**

 * Sends XML-RPC output to the browser.

 *

 * @param string $xml

 *   XML to send to the browser.

 */

function xmlrpc_server_output($xml) {

  $xml = '<?xml version="1.0"?>' . "\n" . $xml;

  drupal_add_http_header('Content-Length', strlen($xml));

  drupal_add_http_header('Content-Type', 'text/xml');

  echo $xml;

  drupal_exit();

}

/**

 * Stores a copy of an XML-RPC request temporarily.

 *

 * @param object $xmlrpc_server

 *   (optional) Request object created by xmlrpc_server(). Omit to leave the

 *   previous server object saved.

 *

 * @return

 *   The latest stored request.

 *

 * @see xmlrpc_server_get()

 */

function xmlrpc_server_set($xmlrpc_server = NULL) {

  static $server;

  if (!isset($server)) {

    $server = $xmlrpc_server;

  }

  return $server;

}

/**

 * Retrieves the latest stored XML-RPC request.

 *

 * @return object

 *   The stored request.

 *

 * @see xmlrpc_server_set()

 */

function xmlrpc_server_get() {

  return xmlrpc_server_set();

}

/**

 * Dispatches an XML-RPC request and any parameters to the appropriate handler.

 *

 * @param object $xmlrpc_server

 *   Object containing information about this XML-RPC server, the methods it

 *   provides, their signatures, etc.

 * @param string $methodname

 *   The external XML-RPC method name; e.g., 'system.methodHelp'.

 * @param array $args

 *   Array containing any parameters that are to be sent along with the request.

 *

 * @return

 *   The results of the call.

 */

function xmlrpc_server_call($xmlrpc_server, $methodname, $args) {

  // Make sure parameters are in an array

  if ($args && !is_array($args)) {

    $args = array($args);

  }

  // Has this method been mapped to a Drupal function by us or by modules?

  if (!isset($xmlrpc_server->callbacks[$methodname])) {

    return xmlrpc_error(-32601, t('Server error. Requested method @methodname not specified.', array("@methodname" => $xmlrpc_server->message->methodname)));

  }

  $method = $xmlrpc_server->callbacks[$methodname];

  $signature = $xmlrpc_server->signatures[$methodname];

  // If the method has a signature, validate the request against the signature

  if (is_array($signature)) {

    $ok = TRUE;

    $return_type = array_shift($signature);

    // Check the number of arguments

    if (count($args) != count($signature)) {

      return xmlrpc_error(-32602, t('Server error. Wrong number of method parameters.'));

    }

    // Check the argument types

    foreach ($signature as $key => $type) {

      $arg = $args[$key];

      switch ($type) {

        case 'int':

        case 'i4':

          if (is_array($arg) || !is_int($arg)) {

            $ok = FALSE;

          }

          break;

        case 'base64':

        case 'string':

          if (!is_string($arg)) {

            $ok = FALSE;

          }

          break;

        case 'boolean':

          if ($arg !== FALSE && $arg !== TRUE) {

            $ok = FALSE;

          }

          break;

        case 'float':

        case 'double':

          if (!is_float($arg)) {

            $ok = FALSE;

          }

          break;

        case 'date':

        case 'dateTime.iso8601':

          if (!$arg->is_date) {

            $ok = FALSE;

          }

          break;

      }

      if (!$ok) {

        return xmlrpc_error(-32602, t('Server error. Invalid method parameters.'));

      }

    }

  }

  if (!function_exists($method)) {

    return xmlrpc_error(-32601, t('Server error. Requested function @method does not exist.', array("@method" => $method)));

  }

  // Call the mapped function

  return call_user_func_array($method, $args);

}

/**

 * Dispatches multiple XML-RPC requests.

 *

 * @param array $methodcalls

 *   An array of XML-RPC requests to make. Each request is an array with the

 *   following elements:

 *   - methodName: Name of the method to invoke.

 *   - params: Parameters to pass to the method.

 *

 * @return

 *   An array of the results of each request.

 *

 * @see xmlrpc_server_call()

 */

function xmlrpc_server_multicall($methodcalls) {

  // See http://www.xmlrpc.com/discuss/msgReader$1208

  // To avoid multicall expansion attacks, limit the number of duplicate method

  // calls allowed with a default of 1. Set to -1 for unlimited.

  $duplicate_method_limit = variable_get('xmlrpc_multicall_duplicate_method_limit', 1);

  $method_count = array();

  $return = array();

  $xmlrpc_server = xmlrpc_server_get();

  foreach ($methodcalls as $call) {

    $ok = TRUE;

    if (!isset($call['methodName']) || !isset($call['params'])) {

      $result = xmlrpc_error(3, t('Invalid syntax for system.multicall.'));

      $ok = FALSE;

    }

    $method = $call['methodName'];

    $method_count[$method] = isset($method_count[$method]) ? $method_count[$method] + 1 : 1;

    $params = $call['params'];

    if ($method == 'system.multicall') {

      $result = xmlrpc_error(-32600, t('Recursive calls to system.multicall are forbidden.'));

    }

    elseif ($duplicate_method_limit > 0 && $method_count[$method] > $duplicate_method_limit) {

      $result = xmlrpc_error(-156579, t('Too many duplicate method calls in system.multicall.'));

    }

    elseif ($ok) {

      $result = xmlrpc_server_call($xmlrpc_server, $method, $params);

    }

    if (is_object($result) && !empty($result->is_error)) {

      $return[] = array(

        'faultCode' => $result->code,

        'faultString' => $result->message,

      );

    }

    else {

      $return[] = array($result);

    }

  }

  return $return;

}

/**

 * Lists the methods available on this XML-RPC server.

 *

 * XML-RPC method system.listMethods maps to this function.

 *

 * @return array

 *   Array of the names of methods available on this server.

 */

function xmlrpc_server_list_methods() {

  $xmlrpc_server = xmlrpc_server_get();

  return array_keys($xmlrpc_server->callbacks);

}

/**

 * Returns a list of the capabilities of this server.

 *

 * XML-RPC method system.getCapabilities maps to this function.

 *

 * @return array

 *   Array of server capabilities.

 *

 * @see http://groups.yahoo.com/group/xml-rpc/message/2897

 */

function xmlrpc_server_get_capabilities() {

  return array(

    'xmlrpc' => array(

      'specUrl' => 'http://www.xmlrpc.com/spec',

      'specVersion' => 1,

    ),

    'faults_interop' => array(

      'specUrl' => 'http://xmlrpc-epi.sourceforge.net/specs/rfc.fault_codes.php',

      'specVersion' => 20010516,

    ),

    'system.multicall' => array(

      'specUrl' => 'http://www.xmlrpc.com/discuss/msgReader$1208',

      'specVersion' => 1,

    ),

    'introspection' => array(

      'specUrl' => 'http://scripts.incutio.com/xmlrpc/introspection.html',

      'specVersion' => 1,

    ),

  );

}

/**

 * Returns one method signature for a function.

 *

 * This is the function mapped to the XML-RPC method system.methodSignature.

 *

 * A method signature is an array of the input and output types of a method. For

 * instance, the method signature of this function is array('array', 'string'),

 * because it takes an array and returns a string.

 *

 * @param string $methodname

 *   Name of method to return a method signature for.

 *

 * @return array

 *   An array of arrays of types, each of the arrays representing one method

 *   signature of the function that $methodname maps to.

 */

function xmlrpc_server_method_signature($methodname) {

  $xmlrpc_server = xmlrpc_server_get();

  if (!isset($xmlrpc_server->callbacks[$methodname])) {

    return xmlrpc_error(-32601, t('Server error. Requested method @methodname not specified.', array("@methodname" => $methodname)));

  }

  if (!is_array($xmlrpc_server->signatures[$methodname])) {

    return xmlrpc_error(-32601, t('Server error. Requested method @methodname signature not specified.', array("@methodname" => $methodname)));

  }

  // We array of types

  $return = array();

  foreach ($xmlrpc_server->signatures[$methodname] as $type) {

    $return[] = $type;

  }

  return array($return);

}

/**

 * Returns the help for an XML-RPC method.

 *

 * XML-RPC method system.methodHelp maps to this function.

 *

 * @param string $method

 *   Name of method for which we return a help string.

 *

 * @return string

 *   Help text for $method.

 */

function xmlrpc_server_method_help($method) {

  $xmlrpc_server = xmlrpc_server_get();

  return $xmlrpc_server->help[$method];

}