1// Copyright (C) 2003-2015 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 3, 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 COPYING3.  If not see
16// <http://www.gnu.org/licenses/>.
17
18// 27.8.1.4 Overridden virtual functions
19
20#include <locale>
21#include <fstream>
22#include <testsuite_hooks.h>
23
24class Cvt : public std::codecvt<wchar_t, char, std::mbstate_t>
25{
26public:
27  mutable bool unshift_called;
28
29  Cvt()
30  : unshift_called(false)
31  { }
32
33protected:
34  bool
35  do_always_noconv() const throw()
36  { return false; }
37
38  int
39  do_encoding() const throw()
40  { return -1; }
41
42  std::codecvt_base::result
43  do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const
44  {
45    unshift_called = true;
46    to_next = to;
47    return std::codecvt_base::ok;
48  }
49};
50
51// libstdc++/12790
52// basic_filebuf::seekoff() should call codecvt::unshift()
53void test01()
54{
55  using namespace std;
56
57  bool test __attribute__((unused)) = true;
58  const char* name = "tmp_seekoff_12790";
59
60  Cvt* cvt = new Cvt;
61  locale loc(locale::classic(), cvt);
62
63  wfilebuf fb;
64  fb.pubsetbuf(0, 0);
65  fb.pubimbue(loc);
66
67  fb.open(name, ios_base::out);
68  fb.sputc(L'a');
69
70  VERIFY( !cvt->unshift_called );
71  fb.pubseekoff(0, ios_base::cur);
72  VERIFY( cvt->unshift_called );
73}
74
75int main()
76{
77  test01();
78  return 0;
79}
80