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// <ostream>
11
12// template <class charT, class traits = char_traits<charT> >
13//   class basic_ostream;
14
15// basic_ostream& write(const char_type* s, streamsize n);
16
17#include <ostream>
18#include <cassert>
19
20template <class CharT>
21class testbuf
22    : public std::basic_streambuf<CharT>
23{
24    typedef std::basic_streambuf<CharT> base;
25    std::basic_string<CharT> str_;
26public:
27    testbuf()
28    {
29    }
30
31    std::basic_string<CharT> str() const
32        {return std::basic_string<CharT>(base::pbase(), base::pptr());}
33
34protected:
35
36    virtual typename base::int_type
37        overflow(typename base::int_type ch = base::traits_type::eof())
38        {
39            if (ch != base::traits_type::eof())
40            {
41                int n = static_cast<int>(str_.size());
42                str_.push_back(static_cast<CharT>(ch));
43                str_.resize(str_.capacity());
44                base::setp(const_cast<CharT*>(str_.data()),
45                           const_cast<CharT*>(str_.data() + str_.size()));
46                base::pbump(n+1);
47            }
48            return ch;
49        }
50};
51
52int main()
53{
54    {
55        std::wostream os((std::wstreambuf*)0);
56        const wchar_t s[] = L"123456790";
57        os.write(s, sizeof(s)/sizeof(s[0])-1);
58        assert(os.bad());
59    }
60    {
61        testbuf<wchar_t> sb;
62        std::wostream os(&sb);
63        const wchar_t s[] = L"123456790";
64        os.write(s, sizeof(s)/sizeof(s[0])-1);
65        assert(os.good());
66        assert(sb.str() == s);
67    }
68    {
69        testbuf<char> sb;
70        std::ostream os(&sb);
71        const char s[] = "123456790";
72        os.write(s, sizeof(s)/sizeof(s[0])-1);
73        assert(sb.str() == s);
74        assert(os.good());
75    }
76}
77