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 // operator<<(const void* val);
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:
testbuf()28     testbuf()
29     {
30     }
31 
str() const32     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
overflow(typename base::int_type ch=base::traits_type::eof ())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 
main(int,char **)53 int main(int, char**)
54 {
55     {
56         std::ostream os((std::streambuf*)0);
57         const void* n = 0;
58         os << n;
59         assert(os.bad());
60         assert(os.fail());
61     }
62     {
63         testbuf<char> sb1;
64         std::ostream os1(&sb1);
65         int n1;
66         os1 << &n1;
67         assert(os1.good());
68         std::string s1(sb1.str());
69 
70         testbuf<char> sb2;
71         std::ostream os2(&sb2);
72         int n2;
73         os2 << &n2;
74         assert(os2.good());
75         std::string s2(sb2.str());
76 
77         // %p is implementation defined. Instead of validating the
78         // output, at least ensure that it does not generate an empty
79         // string. Also make sure that given two distinct addresses, the
80         // output of %p is different.
81         assert(!s1.empty());
82         assert(!s2.empty());
83         assert(s1 != s2);
84     }
85     {
86         testbuf<char> sb;
87         std::ostream os(&sb);
88         const void* n = &sb;
89         os << n;
90         assert(os.good());
91     }
92 
93   return 0;
94 }
95