libstdc++-v3/testsuite/27_io/basic_istream/tellg/wchar_t/sstream.cc

   1 // Copyright (C) 2004-2023 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 // 27.6.1.3 unformatted input functions
  19 // NB: ostream has a particular "seeks" category. Adopt this for istreams too.
  20 // @require@ %-*.tst %-*.txt
  21 // @diff@ %-*.tst %-*.txt
  22
  23 // { dg-require-fileio "" }
  24
  25 #include <istream>
  26 #include <sstream>
  27 #include <fstream>
  28 #include <testsuite_hooks.h>
  29
  30 // stringstreams
  31 void test05(void)
  32 {
  33   typedef std::wistream::off_type off_type;
  34
  35   std::wistream::pos_type pos01, pos02, pos03, pos04, pos05, pos06;
  36   std::ios_base::iostate state01, state02;
  37   const char str_lit01[] = "wistream_seeks-1.tst";
  38   std::wifstream if01(str_lit01);
  39   std::wifstream if02(str_lit01);
  40   std::wifstream if03(str_lit01);
  41   VERIFY( if01.good() );
  42   VERIFY( if02.good() );
  43   VERIFY( if03.good() );
  44
  45   std::wstringbuf strbuf01(std::ios_base::in | std::ios_base::out);
  46   if01 >> &strbuf01;
  47   // initialize stringbufs that are ios_base::out
  48   std::wstringbuf strbuf03(strbuf01.str(), std::ios_base::out);
  49   // initialize stringbufs that are ios_base::in
  50   std::wstringbuf strbuf02(strbuf01.str(), std::ios_base::in);
  51
  52   std::wistream is01(&strbuf01);
  53   std::wistream is02(&strbuf02);
  54   std::wistream is03(&strbuf03);
  55
  56   // pos_type tellg()
  57   // in | out
  58   pos01 = is01.tellg();
  59   pos02 = is01.tellg();
  60   VERIFY( pos01 == pos02 );
  61
  62   // in
  63   pos03 = is02.tellg();
  64   pos04 = is02.tellg();
  65   VERIFY( pos03 == pos04 );
  66
  67   // out
  68   pos05 = is03.tellg();
  69   pos06 = is03.tellg();
  70   VERIFY( pos05 == pos06 );
  71
  72   // cur
  73   // NB: see library issues list 136. It's the v-3 interp that seekg
  74   // only sets the input buffer, or else istreams with buffers that
  75   // have _M_mode == ios_base::out will fail to have consistency
  76   // between seekg and tellg.
  77   state01 = is01.rdstate();
  78   is01.seekg(10, std::ios_base::cur);
  79   state02 = is01.rdstate();
  80   pos01 = is01.tellg();
  81   VERIFY( pos01 == pos02 + off_type(10) );
  82   VERIFY( state01 == state02 );
  83   pos02 = is01.tellg();
  84   VERIFY( pos02 == pos01 );
  85 }
  86
  87 int main()
  88 {
  89   test05();
  90   return 0;
  91 }