libstdc++-v3/testsuite/27_io/basic_istream/seekg/char/sstream.cc

   1 // 2000-06-29 bkoz
   2
   3 // Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation
   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 2, 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 COPYING.  If not, write to the Free
  18 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  19 // USA.
  20
  21 // 27.6.1.3 unformatted input functions
  22 // NB: ostream has a particular "seeks" category. Adopt this for istreams too.
  23 // @require@ %-*.tst %-*.txt
  24 // @diff@ %-*.tst %-*.txt
  25
  26 // { dg-require-fileio "" }
  27
  28 #include <istream>
  29 #include <sstream>
  30 #include <fstream>
  31 #include <testsuite_hooks.h>
  32
  33 // stringstreams
  34 void test05(void)
  35 {
  36   typedef std::istream::off_type off_type;
  37
  38   bool test __attribute__((unused)) = true;
  39   std::istream::pos_type pos01, pos02, pos03, pos04, pos05, pos06;
  40   std::ios_base::iostate state01, state02;
  41   const char str_lit01[] = "istream_seeks-1.tst";
  42   std::ifstream if01(str_lit01);
  43   std::ifstream if02(str_lit01);
  44   std::ifstream if03(str_lit01);
  45   VERIFY( if01.good() );
  46   VERIFY( if02.good() );
  47   VERIFY( if03.good() );
  48
  49   std::stringbuf strbuf01(std::ios_base::in | std::ios_base::out);
  50   if01 >> &strbuf01;
  51   // initialize stringbufs that are ios_base::out
  52   std::stringbuf strbuf03(strbuf01.str(), std::ios_base::out);
  53   // initialize stringbufs that are ios_base::in
  54   std::stringbuf strbuf02(strbuf01.str(), std::ios_base::in);
  55
  56   std::istream is01(&strbuf01);
  57   std::istream is02(&strbuf02);
  58   std::istream is03(&strbuf03);
  59
  60   // pos_type tellg()
  61   // in | out
  62   pos01 = is01.tellg();
  63   pos02 = is01.tellg();
  64   pos03 = is02.tellg();
  65   pos04 = is02.tellg();
  66   pos05 = is03.tellg();
  67   pos06 = is03.tellg();
  68
  69   // istream& seekg(pos_type)
  70   // istream& seekg(off_type, ios_base::seekdir)
  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   state01 = is02.rdstate();
  87   is02.seekg(10, std::ios_base::cur);
  88   state02 = is02.rdstate();
  89   pos03 = is02.tellg();
  90   VERIFY( pos03 == pos04 + off_type(10) );
  91   VERIFY( state01 == state02 );
  92   pos04 = is02.tellg();
  93   VERIFY( pos03 == pos04 );
  94
  95   state01 = is03.rdstate();
  96   is03.seekg(10, std::ios_base::cur);
  97   state02 = is03.rdstate();
  98   pos05 = is03.tellg();
  99   VERIFY( pos05 == pos06 ); // as only out buffer
 100   VERIFY( state01 != state02 );
 101   pos06 = is03.tellg();
 102   VERIFY( pos05 == pos06 );
 103
 104   // beg
 105   state01 = is01.rdstate();
 106   is01.seekg(20, std::ios_base::beg);
 107   state02 = is01.rdstate();
 108   pos01 = is01.tellg();
 109   VERIFY( pos01 == pos02 + off_type(10) );
 110   VERIFY( state01 == state02 );
 111   pos02 = is01.tellg();
 112   VERIFY( pos02 == pos01 );
 113
 114   state01 = is02.rdstate();
 115   is02.seekg(20, std::ios_base::beg);
 116   state02 = is02.rdstate();
 117   pos03 = is02.tellg();
 118   VERIFY( pos03 == pos04 + off_type(10) );
 119   VERIFY( state01 == state02 );
 120   pos04 = is02.tellg();
 121   VERIFY( pos03 == pos04 );
 122
 123   state01 = is03.rdstate();
 124   is03.seekg(20, std::ios_base::beg);
 125   state02 = is03.rdstate();
 126   pos05 = is03.tellg();
 127   VERIFY( pos05 == pos06 ); // as only out buffer
 128   VERIFY( state01 == state02 );
 129   pos06 = is03.tellg();
 130   VERIFY( pos05 == pos06 );
 131 }
 132
 133 int main()
 134 {
 135   test05();
 136   return 0;
 137 }