libstdc++-v3/testsuite/27_io/objects/char/5.cc

   1 // 2003-04-26 Petur Runolfsson  <peturr02@ru.is>
   2
   3 // Copyright (C) 2003-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 // 27.3 Standard iostream objects
  21
  22 // Check that standard streams can be used from constructors and
  23 // destructors of static objects, provided that an instance of
  24 // ios_base::Init has been constructed.
  25
  26 void init_standard_streams();
  27 int use_standard_streams();
  28
  29 struct Strange
  30 {
  31   int i;
  32
  33   Strange()
  34   {
  35     init_standard_streams();
  36     i = use_standard_streams();
  37   }
  38
  39   ~Strange()
  40   {
  41     use_standard_streams();
  42     init_standard_streams();
  43   }
  44 };
  45
  46 static Strange static_ob;
  47
  48 #include <testsuite_hooks.h>
  49 #include <iostream>
  50
  51 void init_standard_streams()
  52 {
  53   std::ios_base::Init init;
  54 }
  55
  56 int use_standard_streams()
  57 {
  58   std::cout << "Hello, world!" << std::endl;
  59   std::cerr << "World, hello!" << std::endl;
  60
  61   int ret = std::ios_base::xalloc();
  62   std::cin.iword(ret) = ret + 1;
  63   std::cout.iword(ret) = ret + 2;
  64   std::cerr.iword(ret) = ret + 3;
  65   std::clog.iword(ret) = ret + 4;
  66   return ret;
  67 }
  68
  69 void test05()
  70 {
  71   int i = static_ob.i;
  72
  73   VERIFY( std::cin.iword(i) == i + 1 );
  74   VERIFY( std::cout.iword(i) == i + 2 );
  75   VERIFY( std::cerr.iword(i) == i + 3 );
  76   VERIFY( std::clog.iword(i) == i + 4 );
  77 }
  78
  79 int main()
  80 {
  81   test05();
  82   return 0;
  83 }