1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <fstream>
11
12// pos_type seekoff(off_type off, ios_base::seekdir way,
13//                  ios_base::openmode which = ios_base::in | ios_base::out);
14// pos_type seekpos(pos_type sp,
15//                  ios_base::openmode which = ios_base::in | ios_base::out);
16
17// This test is not entirely portable
18
19#include <fstream>
20#include <cassert>
21
22template <class CharT>
23struct test_buf
24    : public std::basic_filebuf<CharT>
25{
26    typedef std::basic_filebuf<CharT> base;
27    typedef typename base::char_type  char_type;
28    typedef typename base::int_type   int_type;
29    typedef typename base::pos_type   pos_type;
30
31    char_type* eback() const {return base::eback();}
32    char_type* gptr()  const {return base::gptr();}
33    char_type* egptr() const {return base::egptr();}
34    void gbump(int n) {base::gbump(n);}
35
36    virtual int_type underflow() {return base::underflow();}
37};
38
39int main()
40{
41    {
42        char buf[10];
43        typedef std::filebuf::pos_type pos_type;
44        std::filebuf f;
45        f.pubsetbuf(buf, sizeof(buf));
46        assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
47                                                       | std::ios_base::trunc) != 0);
48        assert(f.is_open());
49        f.sputn("abcdefghijklmnopqrstuvwxyz", 26);
50        assert(buf[0] == 'v');
51        pos_type p = f.pubseekoff(-15, std::ios_base::cur);
52        assert(p == 11);
53        assert(f.sgetc() == 'l');
54        f.pubseekoff(0, std::ios_base::beg);
55        assert(f.sgetc() == 'a');
56        f.pubseekoff(-1, std::ios_base::end);
57        assert(f.sgetc() == 'z');
58        assert(f.pubseekpos(p) == p);
59        assert(f.sgetc() == 'l');
60    }
61    std::remove("seekoff.dat");
62    {
63        wchar_t buf[10];
64        typedef std::filebuf::pos_type pos_type;
65        std::wfilebuf f;
66        f.pubsetbuf(buf, sizeof(buf)/sizeof(buf[0]));
67        assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
68                                                       | std::ios_base::trunc) != 0);
69        assert(f.is_open());
70        f.sputn(L"abcdefghijklmnopqrstuvwxyz", 26);
71        assert(buf[0] == L'v');
72        pos_type p = f.pubseekoff(-15, std::ios_base::cur);
73        assert(p == 11);
74        assert(f.sgetc() == L'l');
75        f.pubseekoff(0, std::ios_base::beg);
76        assert(f.sgetc() == L'a');
77        f.pubseekoff(-1, std::ios_base::end);
78        assert(f.sgetc() == L'z');
79        assert(f.pubseekpos(p) == p);
80        assert(f.sgetc() == L'l');
81    }
82    std::remove("seekoff.dat");
83}
84