// vi:set ft=cpp: -*- Mode: C++ -*-
/**
 * \file
 * Meta interface for getting dynamic type information about objects behind
 * capabilities.
 */
/*
 * (c) 2008-2009 Alexander Warg <warg@os.inf.tu-dresden.de>
 *     economic rights: Technische Universität Dresden (Germany)
 *
 * This file is part of TUD:OS and distributed under the terms of the
 * GNU General Public License 2.
 * Please see the COPYING-GPL-2 file for details.
 *
 * As a special exception, you may use this file as part of a free software
 * library without restriction.  Specifically, if other files instantiate
 * templates or use macros or inline functions from this file, or you compile
 * this file and link it with other files to produce an executable, this
 * file does not by itself cause the resulting executable to be covered by
 * the GNU General Public License.  This exception does not however
 * invalidate any other reasons why the executable file might be covered by
 * the GNU General Public License.
 */

#pragma once

#include "kobject"
#include "cxx/ipc_iface"
#include "cxx/ipc_string"

namespace L4 {

/**
 * Meta interface that shall be implemented by each L4Re object
 * and gives access to the dynamic type information for L4Re objects.
 */
class Meta : public Kobject_t<Meta, Kobject, L4_PROTO_META>
{
public:
  /**
   * Get the number of interfaces implemented by this object.
   *
   * \retval l4_msgtag_t::label() >= 0  The number of supported interfaces.
   * \retval l4_msgtag_t::label() < 0   Error code of the occurred error.
   */
  L4_INLINE_RPC(l4_msgtag_t, num_interfaces, ());

  /**
   * Get the protocol number that must be used for the interface with
   * the number `idx`.
   *
   * \param      idx    The index of the interface to get the protocol
   *                    number for. `idx` must be >= 0 and < the return
   *                    value of num_interfaces().
   * \param[out] proto  The protocol number for interface `idx`.
   * \param[out] name   The protocol name for interface `idx`.
   *
   * \retval l4_msgtag_t::label() == 0  Successful; see `proto` and `name`.
   * \retval l4_msgtag_t::label() < 0   Error code.
   */
  L4_INLINE_RPC(l4_msgtag_t, interface, (l4_umword_t idx, long *proto,
                                         L4::Ipc::String<char> *name));

  /**
   * Figure out if the object supports the given protocol (number).
   *
   * \param protocol  The protocol number to check for.
   *
   * \retval l4_msgtag_t::label() == 1  protocol is supported.
   * \retval l4_msgtag_t::label() == 0  protocol is not supported.
   *
   * This method is intended to be used for statically assigned protocol
   * numbers.
   */
  L4_INLINE_RPC(l4_msgtag_t, supports, (l4_mword_t protocol));

  typedef L4::Typeid::Rpcs<num_interfaces_t, interface_t, supports_t> Rpcs;
};

}