libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/wchar_t/11544-1.cc

   1 // Copyright (C) 2003-2020 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // 27.8.1.4 Overridden virtual functions
  19
  20 #include <fstream>
  21 #include <locale>
  22 #include <cstdio>
  23 #include <testsuite_hooks.h>
  24
  25 template <typename InternT, typename StateT = mbstate_t>
  26 class checksumcvt : public std::codecvt<InternT, char, StateT>
  27 {
  28   typedef std::codecvt<InternT, char, StateT> Base;
  29   static const size_t width = sizeof(InternT) + 1;
  30
  31 public:
  32   typedef InternT intern_type;
  33   typedef char extern_type;
  34
  35   explicit checksumcvt(size_t refs = 0)
  36   : Base(refs)
  37   { }
  38
  39 protected:
  40   virtual typename std::codecvt<InternT, char, StateT>::result
  41   do_out(StateT&, const intern_type* from,
  42          const intern_type* from_end, const intern_type*& from_next,
  43          extern_type* to, extern_type* to_end,
  44          extern_type*& to_next) const
  45   {
  46     size_t len = std::min(static_cast<size_t>(from_end - from),
  47                           static_cast<size_t>(to_end - to) / width);
  48
  49     while (len--)
  50       {
  51         const char* p = reinterpret_cast<const char*>(from);
  52         unsigned char checksum = 0;
  53
  54         for (size_t i = 0; i < sizeof(intern_type); ++i)
  55           {
  56             *to++ = p[i];
  57             checksum ^= static_cast<unsigned char>(p[i]);
  58           }
  59
  60         *to++ = checksum;
  61         ++from;
  62       }
  63
  64     from_next = from;
  65     to_next = to;
  66     return from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
  67            : std::codecvt<InternT, char, StateT>::partial;
  68   }
  69
  70   virtual typename std::codecvt<InternT, char, StateT>::result
  71   do_unshift(StateT&, extern_type* to,
  72              extern_type*, extern_type*& to_next) const
  73   {
  74     to_next = to;
  75     return std::codecvt<InternT, char, StateT>::ok;
  76   }
  77
  78   virtual typename std::codecvt<InternT, char, StateT>::result
  79   do_in(StateT&, const extern_type* from,
  80         const extern_type* from_end, const extern_type*& from_next,
  81         intern_type* to, intern_type* to_end,
  82         intern_type*& to_next) const
  83   {
  84     size_t len = std::min(static_cast<size_t>(to_end - to),
  85                           static_cast<size_t>(from_end - from) / width);
  86
  87     while (len)
  88       {
  89         const char* f = from;
  90         intern_type tmp;
  91         char* p = reinterpret_cast<char*>(&tmp);
  92         unsigned char checksum = 0;
  93
  94         for (size_t i = 0; i < sizeof(intern_type); ++i)
  95           {
  96             p[i] = *f;
  97             checksum ^= static_cast<unsigned char>(*f++);
  98           }
  99
 100         if (*f++ != checksum)
 101           break;
 102
 103         from = f;
 104         *to++ = tmp;
 105         len--;
 106       }
 107
 108     from_next = from;
 109     to_next = to;
 110     return len ? std::codecvt<InternT, char, StateT>::error :
 111       (from_next == from_end ? std::codecvt<InternT, char, StateT>::ok
 112        : std::codecvt<InternT, char, StateT>::partial);
 113   }
 114
 115   virtual int
 116   do_encoding() const throw()
 117   { return width; }
 118
 119   virtual int
 120   do_length(StateT&, const extern_type* from,
 121             const extern_type* end, size_t max) const
 122   {
 123     size_t len = std::min(max, static_cast<size_t>(end - from) / width);
 124
 125     int ret = 0;
 126     while (len--)
 127       {
 128         unsigned char checksum = 0;
 129
 130         for (size_t i = 0; i < sizeof(intern_type); ++i)
 131           {
 132             checksum ^= static_cast<unsigned char>(*from++);
 133           }
 134
 135         if (*from++ != checksum)
 136           break;
 137
 138         ret++;
 139       }
 140
 141     return ret;
 142   }
 143
 144   virtual int
 145   do_max_length() const throw()
 146   { return width; }
 147
 148   virtual bool
 149   do_always_noconv() const throw()
 150   { return false; }
 151 };
 152
 153 // libstdc++/11544 (incomplete character in file)
 154 void test01()
 155 {
 156   using namespace std;
 157
 158   locale loc(locale::classic(), new checksumcvt<wchar_t>);
 159
 160   const char* name = "tmp_11544-1";
 161
 162   FILE* f = fopen(name, "w");
 163   putc('a', f);
 164   fclose(f);
 165
 166   wifstream in;
 167   in.imbue(loc);
 168   in.open(name);
 169
 170   VERIFY( in.good() );
 171   in.get();
 172   VERIFY( !in.good() );
 173   VERIFY( in.bad() );
 174   VERIFY( !in.eof() );
 175
 176   in.close();
 177 }
 178
 179 int main()
 180 {
 181   test01();
 182   return 0;
 183 }