1// Copyright (C) 2003, 2009 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// { dg-require-fileio "" } 21 22#include <locale> 23#include <fstream> 24#include <testsuite_hooks.h> 25 26class Cvt : public std::codecvt<char, char, std::mbstate_t> 27{ 28public: 29 mutable bool unshift_called; 30 31 Cvt() 32 : unshift_called(false) 33 { } 34 35protected: 36 bool 37 do_always_noconv() const throw() 38 { return false; } 39 40 int 41 do_encoding() const throw() 42 { return -1; } 43 44 std::codecvt_base::result 45 do_unshift(std::mbstate_t&, char* to, char*, char*& to_next) const 46 { 47 unshift_called = true; 48 to_next = to; 49 return std::codecvt_base::ok; 50 } 51}; 52 53// libstdc++/12790 54// basic_filebuf::seekpos() should call codecvt::unshift() 55void test01() 56{ 57 using namespace std; 58 59 bool test __attribute__((unused)) = true; 60 const char* name = "tmp_seekpos_12790"; 61 62 Cvt* cvt = new Cvt; 63 locale loc(locale::classic(), cvt); 64 65 filebuf fb; 66 fb.pubimbue(loc); 67 68 fb.open(name, ios_base::out); 69 streampos pos = fb.pubseekoff(0, ios_base::beg); 70 fb.sputc('a'); 71 fb.pubsync(); // Does not call unshift() 72 73 VERIFY( !cvt->unshift_called ); 74 fb.pubseekpos(pos); 75 VERIFY( cvt->unshift_called ); 76} 77 78int main() 79{ 80 test01(); 81 return 0; 82} 83