libstdc++-v3/testsuite/22_locale/codecvt/length/wchar_t/5.cc

   1 // 2003-02-06  Petur Runolfsson  <peturr02@ru.is>
   2
   3 // Copyright (C) 2003-2022 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 // 22.2.1.5 - Template class codecvt [lib.locale.codecvt]
  21
  22 #include <locale>
  23 #include <cstring>
  24 #include <testsuite_hooks.h>
  25
  26 // Need to explicitly set the state(mbstate_t) to zero.
  27 // How to do this is not specified by the ISO C99 standard, so we
  28 // might need to add some operators to make the intuiative case
  29 // work:
  30 //   w_codecvt::state_type state00;
  31 //   state00 = 0;
  32 // or, can use this explicit "C" initialization:
  33 //   w_codecvt::state_type state01 = {0, 0};
  34 // .. except Ulrich says: Use memset. Always use memset. Feel the force...
  35 void
  36 zero_state(std::mbstate_t& state)
  37 { std::memset(&state, 0, sizeof(std::mbstate_t)); }
  38
  39 // Required instantiation
  40 // codecvt<wchar_t, char, mbstate_t>
  41 void test05()
  42 {
  43   using namespace std;
  44   typedef codecvt<wchar_t, char, mbstate_t>     w_codecvt;
  45   typedef char                                  ext_type;
  46
  47   const ext_type        e_lit[] = { '\0', '\0', 'f', '\0' };
  48   int                   size = sizeof(e_lit);
  49
  50   locale                loc;
  51   const w_codecvt*      cvt = &use_facet<w_codecvt>(loc);
  52
  53   w_codecvt::state_type state04;
  54   zero_state(state04);
  55   int j = cvt->length(state04, e_lit, e_lit + size, 5);
  56   VERIFY( j == size );
  57 }
  58
  59 int main ()
  60 {
  61   test05();
  62   return 0;
  63 }