libstdc++-v3/testsuite/27_io/basic_filebuf/underflow/char/10097.cc

   1 // { dg-require-fork "" }
   2 // { dg-require-mkfifo "" }
   3
   4 // 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
   5
   6 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
   7 // Free Software Foundation, Inc.
   8 //
   9 // This file is part of the GNU ISO C++ Library.  This library is free
  10 // software; you can redistribute it and/or modify it under the
  11 // terms of the GNU General Public License as published by the
  12 // Free Software Foundation; either version 2, or (at your option)
  13 // any later version.
  14
  15 // This library is distributed in the hope that it will be useful,
  16 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 // GNU General Public License for more details.
  19
  20 // You should have received a copy of the GNU General Public License along
  21 // with this library; see the file COPYING.  If not, write to the Free
  22 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  23 // USA.
  24
  25 // 27.8.1.4 Overridden virtual functions
  26
  27 #include <fstream>
  28 #include <unistd.h>
  29 #include <signal.h>
  30 #include <fcntl.h>
  31 #include <sys/types.h>
  32 #include <sys/stat.h>
  33
  34 // No asserts, avoid leaking the semaphores if a VERIFY fails.
  35 #undef _GLIBCXX_ASSERT
  36
  37 #include <testsuite_hooks.h>
  38
  39 class UnderBuf : public std::filebuf
  40 {
  41 public:
  42   int_type
  43   pub_underflow()
  44   { return underflow(); }
  45
  46   std::streamsize
  47   pub_showmanyc()
  48   { return showmanyc(); }
  49 };
  50
  51 // libstdc++/10097
  52 // filebuf::underflow drops characters.
  53 bool test16()
  54 {
  55   using namespace std;
  56   using namespace __gnu_test;
  57   bool test __attribute__((unused)) = true;
  58
  59   const char* name = "tmp_fifo1";
  60
  61   signal(SIGPIPE, SIG_IGN);
  62   unlink(name);
  63
  64   if (0 != mkfifo(name, S_IRWXU))
  65     {
  66       VERIFY( false );
  67     }
  68
  69   semaphore s1, s2;
  70   int fval = fork();
  71   if (fval == -1)
  72     {
  73       unlink(name);
  74       VERIFY( false );
  75     }
  76   else if (fval == 0)
  77     {
  78       filebuf fbout;
  79       fbout.open(name, ios_base::in|ios_base::out);
  80       VERIFY( fbout.is_open() );
  81       fbout.sputn("0123456789", 10);
  82       fbout.pubsync();
  83       s1.wait();
  84       fbout.close();
  85       s2.signal();
  86       exit(0);
  87     }
  88
  89   UnderBuf fb;
  90   fb.open(name, ios_base::in);
  91
  92   fb.sgetc();
  93   streamsize n = fb.pub_showmanyc();
  94
  95   while (n > 0)
  96     {
  97       --n;
  98
  99       UnderBuf::int_type c = fb.pub_underflow();
 100       VERIFY( c != UnderBuf::traits_type::eof() );
 101
 102       fb.sbumpc();
 103     }
 104
 105   fb.close();
 106   s1.signal();
 107   s2.wait();
 108
 109   return test;
 110 }
 111
 112 int main()
 113 {
 114   return !test16();
 115 }