libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp

   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 // REQUIRES: locale.en_US.UTF-8
  10
  11 // <fstream>
  12
  13 // int_type overflow(int_type c = traits::eof());
  14
  15 // This test is not entirely portable
  16
  17 #include <fstream>
  18 #include <cassert>
  19
  20 #include "test_macros.h"
  21 #include "platform_support.h" // locale name macros
  22
  23 template <class CharT>
  24 struct test_buf
  25     : public std::basic_filebuf<CharT>
  26 {
  27     typedef std::basic_filebuf<CharT>  base;
  28     typedef typename base::char_type   char_type;
  29     typedef typename base::int_type    int_type;
  30     typedef typename base::traits_type traits_type;
  31
  32     char_type* pbase() const {return base::pbase();}
  33     char_type* pptr()  const {return base::pptr();}
  34     char_type* epptr() const {return base::epptr();}
  35     void gbump(int n) {base::gbump(n);}
  36
  37     virtual int_type overflow(int_type c = traits_type::eof()) {return base::overflow(c);}
  38 };
  39
  40 int main(int, char**)
  41 {
  42     {
  43         test_buf<char> f;
  44         assert(f.open("overflow.dat", std::ios_base::out) != 0);
  45         assert(f.is_open());
  46         assert(f.pbase() == 0);
  47         assert(f.pptr() == 0);
  48         assert(f.epptr() == 0);
  49         assert(f.overflow('a') == 'a');
  50         assert(f.pbase() != 0);
  51         assert(f.pptr() == f.pbase());
  52         assert(f.epptr() - f.pbase() == 4095);
  53     }
  54     {
  55         test_buf<char> f;
  56         assert(f.open("overflow.dat", std::ios_base::in) != 0);
  57         assert(f.is_open());
  58         assert(f.sgetc() == 'a');
  59     }
  60     std::remove("overflow.dat");
  61     {
  62         test_buf<char> f;
  63         f.pubsetbuf(0, 0);
  64         assert(f.open("overflow.dat", std::ios_base::out) != 0);
  65         assert(f.is_open());
  66         assert(f.pbase() == 0);
  67         assert(f.pptr() == 0);
  68         assert(f.epptr() == 0);
  69         assert(f.overflow('a') == 'a');
  70         assert(f.pbase() == 0);
  71         assert(f.pptr() == 0);
  72         assert(f.epptr() == 0);
  73     }
  74     {
  75         test_buf<char> f;
  76         assert(f.open("overflow.dat", std::ios_base::in) != 0);
  77         assert(f.is_open());
  78         assert(f.sgetc() == 'a');
  79     }
  80     std::remove("overflow.dat");
  81
  82 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
  83     {
  84         test_buf<wchar_t> f;
  85         assert(f.open("overflow.dat", std::ios_base::out) != 0);
  86         assert(f.is_open());
  87         assert(f.pbase() == 0);
  88         assert(f.pptr() == 0);
  89         assert(f.epptr() == 0);
  90         assert(f.overflow(L'a') == L'a');
  91         assert(f.pbase() != 0);
  92         assert(f.pptr() == f.pbase());
  93         assert(f.epptr() - f.pbase() == 4095);
  94     }
  95     {
  96         test_buf<wchar_t> f;
  97         assert(f.open("overflow.dat", std::ios_base::in) != 0);
  98         assert(f.is_open());
  99         assert(f.sgetc() == L'a');
 100     }
 101     std::remove("overflow.dat");
 102     {
 103         test_buf<wchar_t> f;
 104         f.pubsetbuf(0, 0);
 105         assert(f.open("overflow.dat", std::ios_base::out) != 0);
 106         assert(f.is_open());
 107         assert(f.pbase() == 0);
 108         assert(f.pptr() == 0);
 109         assert(f.epptr() == 0);
 110         assert(f.overflow(L'a') == L'a');
 111         assert(f.pbase() == 0);
 112         assert(f.pptr() == 0);
 113         assert(f.epptr() == 0);
 114     }
 115     {
 116         test_buf<wchar_t> f;
 117         assert(f.open("overflow.dat", std::ios_base::in) != 0);
 118         assert(f.is_open());
 119         assert(f.sgetc() == L'a');
 120     }
 121     std::remove("overflow.dat");
 122     {
 123         test_buf<wchar_t> f;
 124         f.pubimbue(std::locale(LOCALE_en_US_UTF_8));
 125         assert(f.open("overflow.dat", std::ios_base::out) != 0);
 126         assert(f.sputc(0x4E51) == 0x4E51);
 127         assert(f.sputc(0x4E52) == 0x4E52);
 128         assert(f.sputc(0x4E53) == 0x4E53);
 129     }
 130     {
 131         test_buf<char> f;
 132         assert(f.open("overflow.dat", std::ios_base::in) != 0);
 133         assert(f.is_open());
 134         assert(f.sbumpc() == 0xE4);
 135         assert(f.sbumpc() == 0xB9);
 136         assert(f.sbumpc() == 0x91);
 137         assert(f.sbumpc() == 0xE4);
 138         assert(f.sbumpc() == 0xB9);
 139         assert(f.sbumpc() == 0x92);
 140         assert(f.sbumpc() == 0xE4);
 141         assert(f.sbumpc() == 0xB9);
 142         assert(f.sbumpc() == 0x93);
 143         assert(f.sbumpc() == -1);
 144     }
 145     std::remove("overflow.dat");
 146 #endif // TEST_HAS_NO_WIDE_CHARACTERS
 147
 148   return 0;
 149 }