libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/char/4.cc

   1 // { dg-require-fileio "" }
   2
   3 // Copyright (C) 2010-2013 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 // 27.8.1.4 Overridden virtual functions
  21
  22 #include <fstream>
  23 #include <cstring>
  24 #include <testsuite_hooks.h>
  25
  26 void test01()
  27 {
  28   using namespace std;
  29   bool test __attribute__((unused)) = true;
  30
  31   typedef filebuf::pos_type pos_type;
  32   const char name[] = "tmp_seekoff-4.tst";
  33
  34   const size_t size = 12;
  35   char buf[size];
  36   streamsize n;
  37
  38   filebuf fb;
  39   fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
  40
  41   n = fb.sputn("abcd", 4);
  42   VERIFY( n == 4 );
  43
  44   fb.pubseekoff(0, ios_base::beg);
  45   n = fb.sgetn(buf, 3);
  46   VERIFY( n == 3 );
  47   VERIFY( !memcmp(buf, "abc", 3) );
  48
  49   // Check read => write without pubseekoff(0, ios_base::cur)
  50
  51   n = fb.sputn("ef", 2);
  52   VERIFY( n == 2 );
  53
  54   fb.pubseekoff(0, ios_base::beg);
  55
  56   n = fb.sgetn(buf, size);
  57   VERIFY( n == 5 );
  58   VERIFY( !memcmp(buf, "abcef", 5) );
  59
  60   fb.pubseekoff(0, ios_base::beg);
  61   n = fb.sputn("gh", 2);
  62   VERIFY( n == 2 );
  63
  64   // Check write => read without pubseekoff(0, ios_base::cur)
  65
  66   n = fb.sgetn( buf, 3 );
  67   VERIFY( !memcmp(buf, "cef", 3) );
  68
  69   n = fb.sputn("ijkl", 4);
  70   VERIFY( n == 4 );
  71
  72   fb.pubseekoff(0, ios_base::beg);
  73   n = fb.sgetn(buf, 2);
  74   VERIFY( n == 2 );
  75   VERIFY( !memcmp(buf, "gh", 2) );
  76
  77   fb.pubseekoff(0, ios_base::end);
  78   n = fb.sputn("mno", 3);
  79   VERIFY( n == 3 );
  80
  81   fb.pubseekoff(0, ios_base::beg);
  82   n = fb.sgetn(buf, size);
  83   VERIFY( n == 12 );
  84   VERIFY( !memcmp(buf, "ghcefijklmno", 12) );
  85
  86   fb.close();
  87 }
  88
  89 int main()
  90 {
  91   test01();
  92   return 0;
  93 }