1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 // <fstream>
10
11 // pos_type seekoff(off_type off, ios_base::seekdir way,
12 // ios_base::openmode which = ios_base::in | ios_base::out);
13 // pos_type seekpos(pos_type sp,
14 // ios_base::openmode which = ios_base::in | ios_base::out);
15
16 // FILE_DEPENDENCIES: underflow.dat
17
18 #include <fstream>
19 #include <cassert>
20
21 #include "test_macros.h"
22
main(int,char **)23 int main(int, char**)
24 {
25 {
26 char buf[10];
27 typedef std::filebuf::pos_type pos_type;
28 std::filebuf f;
29 f.pubsetbuf(buf, sizeof(buf));
30 assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
31 | std::ios_base::trunc) != 0);
32 assert(f.is_open());
33 f.sputn("abcdefghijklmnopqrstuvwxyz", 26);
34 LIBCPP_ASSERT(buf[0] == 'v');
35 pos_type p = f.pubseekoff(-15, std::ios_base::cur);
36 assert(p == 11);
37 assert(f.sgetc() == 'l');
38 f.pubseekoff(0, std::ios_base::beg);
39 assert(f.sgetc() == 'a');
40 f.pubseekoff(-1, std::ios_base::end);
41 assert(f.sgetc() == 'z');
42 assert(f.pubseekpos(p) == p);
43 assert(f.sgetc() == 'l');
44 }
45 std::remove("seekoff.dat");
46 {
47 wchar_t buf[10];
48 typedef std::filebuf::pos_type pos_type;
49 std::wfilebuf f;
50 f.pubsetbuf(buf, sizeof(buf)/sizeof(buf[0]));
51 assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
52 | std::ios_base::trunc) != 0);
53 assert(f.is_open());
54 f.sputn(L"abcdefghijklmnopqrstuvwxyz", 26);
55 LIBCPP_ASSERT(buf[0] == L'v');
56 pos_type p = f.pubseekoff(-15, std::ios_base::cur);
57 assert(p == 11);
58 assert(f.sgetc() == L'l');
59 f.pubseekoff(0, std::ios_base::beg);
60 assert(f.sgetc() == L'a');
61 f.pubseekoff(-1, std::ios_base::end);
62 assert(f.sgetc() == L'z');
63 assert(f.pubseekpos(p) == p);
64 assert(f.sgetc() == L'l');
65 }
66 std::remove("seekoff.dat");
67
68 return 0;
69 }
70