libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/12790-3.cc

   1 // Copyright (C) 2003 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 2, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING.  If not, write to the Free
  16 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  17 // USA.
  18
  19 // 27.8.1.4 Overridden virtual functions
  20
  21 #include <locale>
  22 #include <fstream>
  23 #include <testsuite_hooks.h>
  24
  25 class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
  26 {
  27 public:
  28   mutable bool unshift_called;
  29
  30   Cvt()
  31   : unshift_called(false)
  32   { }
  33
  34 protected:
  35   bool
  36   do_always_noconv() const throw()
  37   { return false; }
  38
  39   int
  40   do_encoding() const throw()
  41   { return -1; }
  42
  43   std::codecvt_base::result
  44   do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
  45   {
  46     unshift_called = true;
  47     to_next = to;
  48     return std::codecvt_base::ok;
  49   }
  50 };
  51
  52 // libstdc++/12790
  53 // basic_filebuf::seekoff() should call codecvt::unshift(),
  54 // but only if writing
  55 void test01()
  56 {
  57   using namespace std;
  58
  59   bool test __attribute__((unused)) = true;
  60   const char* name = "tmp_seekoff_12790";
  61
  62   Cvt* cvt = new Cvt;
  63   locale loc(locale::classic(), cvt);
  64
  65   wfilebuf fb;
  66   fb.pubimbue(loc);
  67
  68   fb.open(name, ios_base::out);
  69
  70   VERIFY( !cvt->unshift_called );
  71   fb.pubseekoff(0, ios_base::cur);
  72   VERIFY( !cvt->unshift_called );
  73 }
  74
  75 int main()
  76 {
  77   test01();
  78   return 0;
  79 }