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 // basic_istream<charT,traits>& get(char_type* s, streamsize n); 13 14 #include <istream> 15 #include <cassert> 16 17 template <class CharT> 18 struct testbuf 19 : public std::basic_streambuf<CharT> 20 { 21 typedef std::basic_string<CharT> string_type; 22 typedef std::basic_streambuf<CharT> base; 23 private: 24 string_type str_; 25 public: 26 27 testbuf() {} 28 testbuf(const string_type& str) 29 : str_(str) 30 { 31 base::setg(const_cast<CharT*>(str_.data()), 32 const_cast<CharT*>(str_.data()), 33 const_cast<CharT*>(str_.data()) + str_.size()); 34 } 35 36 CharT* eback() const {return base::eback();} 37 CharT* gptr() const {return base::gptr();} 38 CharT* egptr() const {return base::egptr();} 39 }; 40 41 int main() 42 { 43 { 44 testbuf<char> sb(" \n \n "); 45 std::istream is(&sb); 46 char s[5]; 47 is.get(s, 5); 48 assert(!is.eof()); 49 assert(!is.fail()); 50 assert(std::string(s) == " "); 51 assert(is.gcount() == 2); 52 is.get(s, 5); 53 assert(!is.eof()); 54 assert( is.fail()); 55 assert(std::string(s) == ""); 56 assert(is.gcount() == 0); 57 is.clear(); 58 assert(is.get() == '\n'); 59 is.get(s, 5); 60 assert(!is.eof()); 61 assert(!is.fail()); 62 assert(std::string(s) == " "); 63 assert(is.gcount() == 4); 64 assert(is.get() == '\n'); 65 is.get(s, 5); 66 assert( is.eof()); 67 assert(!is.fail()); 68 assert(std::string(s) == " "); 69 assert(is.gcount() == 1); 70 } 71 { 72 testbuf<wchar_t> sb(L" \n \n "); 73 std::wistream is(&sb); 74 wchar_t s[5]; 75 is.get(s, 5); 76 assert(!is.eof()); 77 assert(!is.fail()); 78 assert(std::wstring(s) == L" "); 79 assert(is.gcount() == 2); 80 is.get(s, 5); 81 assert(!is.eof()); 82 assert( is.fail()); 83 assert(std::wstring(s) == L""); 84 assert(is.gcount() == 0); 85 is.clear(); 86 assert(is.get() == L'\n'); 87 is.get(s, 5); 88 assert(!is.eof()); 89 assert(!is.fail()); 90 assert(std::wstring(s) == L" "); 91 assert(is.gcount() == 4); 92 assert(is.get() == L'\n'); 93 is.get(s, 5); 94 assert( is.eof()); 95 assert(!is.fail()); 96 assert(std::wstring(s) == L" "); 97 assert(is.gcount() == 1); 98 } 99 } 100