1 // Copyright (C) 2003-2018 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 <fstream>
21 #include <locale>
22 #include <algorithm>
23 #include <cstring>
24 #include <testsuite_hooks.h>
25
26 class Cvt : public std::codecvt<wchar_t, char, mbstate_t>
27 {
28 protected:
29 virtual std::codecvt_base::result
do_out(std::mbstate_t &,const wchar_t * from,const wchar_t * from_end,const wchar_t * & from_next,char * to,char * to_end,char * & to_next) const30 do_out(std::mbstate_t&, const wchar_t* from, const wchar_t* from_end,
31 const wchar_t*& from_next, char* to, char* to_end,
32 char*& to_next) const
33 {
34 std::size_t from_len = from_end - from;
35 std::size_t to_len = (to_end - to) / sizeof(wchar_t);
36 std::size_t len = std::min(from_len, to_len);
37 std::memcpy(to, from, len * sizeof(wchar_t));
38 from_next = from + len;
39 to_next = to + len * sizeof(wchar_t);
40 return from_next == from_end ? std::codecvt_base::ok :
41 std::codecvt_base::partial;
42 }
43
44 virtual std::codecvt_base::result
do_in(std::mbstate_t &,const char * from,const char * from_end,const char * & from_next,wchar_t * to,wchar_t * to_end,wchar_t * & to_next) const45 do_in(std::mbstate_t&, const char* from, const char* from_end,
46 const char*& from_next, wchar_t* to, wchar_t* to_end,
47 wchar_t*& to_next) const
48 {
49 std::size_t from_len =
50 (from_end - from) / sizeof(wchar_t);
51 std::size_t to_len = to_end - to;
52 std::size_t len = std::min(from_len, to_len);
53 std::memcpy(to, from, len * sizeof(wchar_t));
54 from_next = from + len * sizeof(wchar_t);
55 to_next = to + len;
56 return from_next == from_end ? std::codecvt_base::ok :
57 std::codecvt_base::partial;
58 }
59
60 virtual std::codecvt_base::result
do_unshift(std::mbstate_t &,char *,char *,char * &) const61 do_unshift(std::mbstate_t&, char*, char*, char*&) const
62 { return std::codecvt_base::noconv; }
63
do_encoding() const64 virtual int do_encoding() const throw() { return sizeof(wchar_t); }
do_always_noconv() const65 virtual bool do_always_noconv() const throw() { return false; }
66
67 virtual int
do_length(std::mbstate_t &,const char * from,const char * end,std::size_t max)68 do_length(std::mbstate_t&, const char* from, const char* end,
69 std::size_t max)
70 {
71 std::size_t len = (end - from) / sizeof(wchar_t);
72 return std::min(len, max) * sizeof(wchar_t);
73 }
74
do_max_length() const75 virtual int do_max_length() const throw() { return sizeof(wchar_t); }
76 };
77
test01()78 void test01()
79 {
80 using namespace std;
81
82 // seekoff
83 wfilebuf fb;
84 fb.pubimbue(locale(locale::classic(), new Cvt));
85 fb.open("tmp_9875_seekoff", ios_base::out | ios_base::in | ios_base::trunc);
86 fb.sputn(L"0123456789", 10);
87 fb.pubseekoff(-3, ios_base::cur);
88 VERIFY( fb.sgetc() == L'7' );
89 fb.pubseekoff(-3, ios_base::cur);
90 VERIFY( fb.sgetc() == L'4' );
91 fb.close();
92 }
93
main()94 int main()
95 {
96 test01();
97 return 0;
98 }
99