libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/45628-2.cc

   1 // Copyright (C) 2010-2016 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 // { dg-require-fileio "" }
  19
  20 #include <fstream>
  21 #include <testsuite_hooks.h>
  22 #include <testsuite_character.h>
  23
  24 const char name_01[] = "tmp_seekoff_45628.tst";
  25
  26 unsigned underflows, overflows;
  27
  28 class my_filebuf
  29 : public std::basic_filebuf<__gnu_test::pod_uchar>
  30 {
  31   virtual int_type
  32   underflow()
  33   {
  34     ++underflows;
  35     return std::basic_filebuf<__gnu_test::pod_uchar>::underflow();
  36   }
  37   virtual int_type
  38   overflow(int_type c)
  39   {
  40     ++overflows;
  41     return std::basic_filebuf<__gnu_test::pod_uchar>::overflow(c);
  42   }
  43 };
  44
  45 // libstdc++/45628
  46 void test01()
  47 {
  48   bool test __attribute__((unused)) = true;
  49
  50   using __gnu_test::pod_uchar;
  51   std::locale loc(std::locale::classic(),
  52              new std::codecvt<my_filebuf::traits_type::char_type, char,
  53              my_filebuf::traits_type::state_type>);
  54
  55   my_filebuf::pos_type opos[3], ipos[3];
  56   my_filebuf q;
  57   q.pubimbue(loc);
  58
  59   q.open(name_01, std::ios_base::in | std::ios_base::out
  60          | std::ios_base::trunc);
  61
  62   q.sputc(pod_uchar::from<char>('a'));
  63   opos[0] = q.pubseekoff(0, std::ios_base::cur);
  64   q.sputc(pod_uchar::from<char>('b'));
  65   opos[1] = q.pubseekoff(0, std::ios_base::cur);
  66   q.sputc(pod_uchar::from<char>('c'));
  67   opos[2] = q.pubseekoff(0, std::ios_base::cur);
  68
  69   VERIFY( overflows <= 9 ); // pubseekoff calls overflow twice if converting.
  70   // NB: checking opos==ipos is not very rigorous as long as it flushes, since
  71   // all positions will be at initial state.
  72   q.pubseekoff(0, std::ios_base::beg);
  73
  74   q.sbumpc();
  75   VERIFY( underflows == 1 );
  76
  77   ipos[0] = q.pubseekoff(0, std::ios_base::cur);
  78   VERIFY( ipos[0] == opos[0] );
  79   q.sbumpc();
  80   ipos[1] = q.pubseekoff(0, std::ios_base::cur);
  81   VERIFY( ipos[1] == opos[1] );
  82   q.sbumpc();
  83   ipos[2] = q.pubseekoff(0, std::ios_base::cur);
  84   VERIFY( ipos[2] == opos[2] );
  85
  86   VERIFY( underflows == 1 ); // pubseekoff never flushes get area
  87
  88   // Bonus test: check automatic mode switches.
  89   q.sputc(pod_uchar::from<char>('d'));
  90
  91   q.pubseekpos( ipos[1] );
  92   q.sputc(pod_uchar::from<char>('e'));
  93
  94   VERIFY( my_filebuf::traits_type::eq(
  95                         my_filebuf::traits_type::to_char_type(q.sgetc()),
  96                         pod_uchar::from<char>('d')) );
  97 }
  98
  99 int main()
 100 {
 101   test01();
 102   return 0;
 103 }