sync.pass.cpp revision b64f8b07c104c6cc986570ac8ee0ed16a9f23976 
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// <istream>
11
12// int sync();
13
14#include <istream>
15#include <cassert>
16
17int sync_called = 0;
18
19template <class CharT>
20struct testbuf
21    : public std::basic_streambuf<CharT>
22{
23    typedef std::basic_string<CharT> string_type;
24    typedef std::basic_streambuf<CharT> base;
25private:
26    string_type str_;
27public:
28
29    testbuf() {}
30    testbuf(const string_type& str)
31        : str_(str)
32    {
33        base::setg(const_cast<CharT*>(str_.data()),
34                   const_cast<CharT*>(str_.data()),
35                   const_cast<CharT*>(str_.data()) + str_.size());
36    }
37
38    CharT* eback() const {return base::eback();}
39    CharT* gptr() const {return base::gptr();}
40    CharT* egptr() const {return base::egptr();}
41
42protected:
43    int sync()
44    {
45        ++sync_called;
46        return 5;
47    }
48};
49
50int main()
51{
52    {
53        testbuf<char> sb(" 123456789");
54        std::istream is(&sb);
55        assert(is.sync() == 0);
56        assert(sync_called = 1);
57    }
58    {
59        testbuf<wchar_t> sb(L" 123456789");
60        std::wistream is(&sb);
61        assert(is.sync() == 0);
62        assert(sync_called = 2);
63    }
64}
65