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 // XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
10 
11 // <istream>
12 
13 // basic_istream<charT,traits>& read(char_type* s, streamsize n);
14 
15 #include <istream>
16 #include <cassert>
17 #include "test_macros.h"
18 
19 template <class CharT>
20 struct testbuf
21     : public std::basic_streambuf<CharT>
22 {
23     typedef std::basic_string<CharT> string_type;
24     typedef std::basic_streambuf<CharT> base;
25 private:
26     string_type str_;
27 public:
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 };
42 
43 int main(int, char**)
44 {
45     {
46         testbuf<char> sb(" 123456789");
47         std::istream is(&sb);
48         char s[5];
49         is.read(s, 5);
50         assert(!is.eof());
51         assert(!is.fail());
52         assert(std::string(s, 5) == " 1234");
53         assert(is.gcount() == 5);
54         is.read(s, 5);
55         assert(!is.eof());
56         assert(!is.fail());
57         assert(std::string(s, 5) == "56789");
58         assert(is.gcount() == 5);
59         is.read(s, 5);
60         assert( is.eof());
61         assert( is.fail());
62         assert(is.gcount() == 0);
63     }
64     {
65         testbuf<wchar_t> sb(L" 123456789");
66         std::wistream is(&sb);
67         wchar_t s[5];
68         is.read(s, 5);
69         assert(!is.eof());
70         assert(!is.fail());
71         assert(std::wstring(s, 5) == L" 1234");
72         assert(is.gcount() == 5);
73         is.read(s, 5);
74         assert(!is.eof());
75         assert(!is.fail());
76         assert(std::wstring(s, 5) == L"56789");
77         assert(is.gcount() == 5);
78         is.read(s, 5);
79         assert( is.eof());
80         assert( is.fail());
81         assert(is.gcount() == 0);
82     }
83 #ifndef TEST_HAS_NO_EXCEPTIONS
84     {
85         testbuf<char> sb;
86         std::basic_istream<char> is(&sb);
87         is.exceptions(std::ios_base::eofbit);
88         char s[10];
89         bool threw = false;
90         try {
91             is.read(s, 5);
92         } catch (std::ios_base::failure&) {
93             threw = true;
94         }
95         assert(threw);
96         assert(!is.bad());
97         assert( is.eof());
98         assert( is.fail());
99     }
100     {
101         testbuf<wchar_t> sb;
102         std::basic_istream<wchar_t> is(&sb);
103         is.exceptions(std::ios_base::eofbit);
104         wchar_t s[10];
105         bool threw = false;
106         try {
107             is.read(s, 5);
108         } catch (std::ios_base::failure&) {
109             threw = true;
110         }
111         assert(threw);
112         assert(!is.bad());
113         assert( is.eof());
114         assert( is.fail());
115     }
116 #endif
117 
118     return 0;
119 }
120