ipc_string

// vi:set ft=cpp: -*- Mode: C++ -*-
/*
 * (c) 2014 Alexander Warg <alexander.warg@kernkonzept.com>
 *
 * 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 "types"
#include "ipc_basics"
#include "ipc_array"
 
namespace L4 { namespace Ipc {
 
template<typename CHAR = char const, typename LEN = unsigned long>
struct String : Array<CHAR, LEN>
{
  static LEN strlength(CHAR *d) { LEN l = 0; while (d[l]) ++l; return l; }
  String() {}
  String(CHAR *d) : Array<CHAR, LEN>(strlength(d) + 1, d) {}
  String(LEN len, CHAR *d) : Array<CHAR, LEN>(len, d) {}
  void copy_in(CHAR const *s)
  {
    if (this->length < 1)
      return;
 
    LEN i;
    for (i = 0; i < this->length - 1 && s[i]; ++i)
      this->data[i] = s[i];
    this->length = i + 1;
    this->data[i] = CHAR();
  }
};
 
#if __cplusplus >= 201103L
template< typename CHAR = char, typename LEN_TYPE = unsigned long,
          LEN_TYPE MAX  = (L4_UTCB_GENERIC_DATA_SIZE *
                           sizeof(l4_umword_t)) / sizeof(CHAR) >
using String_in_buf = Array_in_buf<CHAR, LEN_TYPE, MAX>;
#endif
 
namespace Msg {
template<typename A, typename LEN>
struct Clnt_xmit< String<A, LEN> > : Clnt_xmit< Array<A, LEN> > {};
 
template<typename A, typename LEN, typename CLASS>
struct Svr_val_ops< String<A, LEN>, Dir_in, CLASS >
: Svr_val_ops< Array_ref<A, LEN>, Dir_in, CLASS >
{
  typedef Svr_val_ops< Array_ref<A, LEN>, Dir_in, CLASS > Base;
  typedef typename Base::svr_type svr_type;
  using Base::to_svr;
  static int to_svr(char *msg, unsigned offset, unsigned limit,
                    svr_type &a, Dir_in dir, Cls_data cls)
  {
    int r = Base::to_svr(msg, offset, limit, a, dir, cls);
    if (r < 0)
      return r;
 
    // correct clients send at least the zero terminator
    if (a.length < 1)
      return -L4_EMSGTOOSHORT;
 
    typedef typename L4::Types::Remove_const<A>::type elem_type;
    const_cast<elem_type*>(a.data)[a.length - 1] = A();
    return r;
  }
};
 
template<typename A, typename LEN>
struct Clnt_xmit<String<A, LEN> &> : Clnt_xmit<Array<A, LEN> &>
{
  typedef Array<A, LEN> &type;
 
  using Clnt_xmit<type>::from_msg;
  static int from_msg(char *msg, unsigned offset, unsigned limit, long ret,
                      Array<A, LEN> &a, Dir_out dir, Cls_data cls)
  {
    int r = Clnt_xmit<type>::from_msg(msg, offset, limit, ret, a, dir, cls);
    if (r < 0)
      return r;
 
    // check for a bad servers
    if (a.length < 1)
      return -L4_EMSGTOOSHORT;
 
    a.data[a.length - 1] = A();
    return r;
  };
};
 
template<typename A, typename LEN>
struct Clnt_xmit<String<A, LEN> *> : Clnt_xmit<String<A, LEN> &> {};
 
template<typename A, typename LEN, typename CLASS>
struct Svr_val_ops<String<A, LEN>, Dir_out, CLASS>
: Svr_val_ops<Array_ref<A, LEN>, Dir_out, CLASS>
{};
 
template<typename A, typename LEN>
struct Is_valid_rpc_type<String<A, LEN> const *> : L4::Types::False {};
template<typename A, typename LEN>
struct Is_valid_rpc_type<String<A, LEN> const &> : L4::Types::False {};
 
} // namespace Msg
 
}}