1 // Copyright (C) 2003-2024 Free Software Foundation, Inc.
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)
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.
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/>.
18 // 27.8.1.4 Overridden virtual functions
20 // { dg-require-fileio "" }
24 #include <testsuite_hooks.h>
26 class Cvt
: public std::codecvt
<char, char, std::mbstate_t>
29 mutable bool unshift_called
;
32 : unshift_called(false)
37 do_always_noconv() const throw()
41 do_encoding() const throw()
44 std::codecvt_base::result
45 do_unshift(std::mbstate_t&, char* to
, char*, char*& to_next
) const
47 unshift_called
= true;
49 return std::codecvt_base::ok
;
54 // basic_filebuf::seekoff() should call codecvt::unshift(),
55 // but only if writing
60 const char* name
= "tmp_seekoff_12790";
63 locale
loc(locale::classic(), cvt
);
68 fb
.open(name
, ios_base::out
);
70 VERIFY( !cvt
->unshift_called
);
71 fb
.pubseekoff(0, ios_base::cur
);
72 VERIFY( !cvt
->unshift_called
);