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 // <ostream>
10 
11 // template <class charT, class traits = char_traits<charT> >
12 //   class basic_ostream;
13 
14 // basic_ostream& write(const char_type* s, streamsize n);
15 
16 #include <ostream>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
21 template <class CharT>
22 class testbuf
23     : public std::basic_streambuf<CharT>
24 {
25     typedef std::basic_streambuf<CharT> base;
26     std::basic_string<CharT> str_;
27 public:
28     testbuf()
29     {
30     }
31 
32     std::basic_string<CharT> str() const
33         {return std::basic_string<CharT>(base::pbase(), base::pptr());}
34 
35 protected:
36 
37     virtual typename base::int_type
38         overflow(typename base::int_type ch = base::traits_type::eof())
39         {
40             if (ch != base::traits_type::eof())
41             {
42                 int n = static_cast<int>(str_.size());
43                 str_.push_back(static_cast<CharT>(ch));
44                 str_.resize(str_.capacity());
45                 base::setp(const_cast<CharT*>(str_.data()),
46                            const_cast<CharT*>(str_.data() + str_.size()));
47                 base::pbump(n+1);
48             }
49             return ch;
50         }
51 };
52 
53 int main(int, char**)
54 {
55     {
56         std::ostream os((std::streambuf*)0);
57         const char s[] = "123456790";
58         os.write(s, sizeof(s)/sizeof(s[0])-1);
59         assert(os.bad());
60     }
61     {
62         testbuf<char> sb;
63         std::ostream os(&sb);
64         const char s[] = "123456790";
65         os.write(s, sizeof(s)/sizeof(s[0])-1);
66         assert(sb.str() == s);
67         assert(os.good());
68     }
69 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
70     {
71         std::wostream os((std::wstreambuf*)0);
72         const wchar_t s[] = L"123456790";
73         os.write(s, sizeof(s)/sizeof(s[0])-1);
74         assert(os.bad());
75     }
76     {
77         testbuf<wchar_t> sb;
78         std::wostream os(&sb);
79         const wchar_t s[] = L"123456790";
80         os.write(s, sizeof(s)/sizeof(s[0])-1);
81         assert(os.good());
82         assert(sb.str() == s);
83     }
84 #endif
85 
86   return 0;
87 }
88