libstdc++-v3/testsuite/27_io/objects/char/9661-1.cc

   1 // { dg-require-fork "" }
   2 // { dg-require-mkfifo "" }
   3
   4 // 2003-04-30  Petur Runolfsson <peturr02@ru.is>
   5
   6 // Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009, 2010
   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 3, 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 COPYING3.  If not see
  22 // <http://www.gnu.org/licenses/>.
  23
  24 // No asserts, avoid leaking the semaphores if a VERIFY fails.
  25 #undef _GLIBCXX_ASSERT
  26
  27 #include <testsuite_hooks.h>
  28 #include <cstdio>
  29 #include <cstdlib>
  30 #include <iostream>
  31 #include <unistd.h>
  32 #include <signal.h>
  33 #include <fcntl.h>
  34 #include <sys/types.h>
  35 #include <sys/stat.h>
  36
  37 // Check that cin.rdbuf()->sputbackc() puts characters back to stdin.
  38 // If cin.rdbuf() is a filebuf, this succeeds when stdin is a regular
  39 // file, but fails otherwise, hence the named fifo.
  40 bool test01()
  41 {
  42   using namespace std;
  43   using namespace __gnu_test;
  44
  45   bool test __attribute__((unused)) = true;
  46
  47   const char* name = "tmp_fifo5";
  48
  49   signal(SIGPIPE, SIG_IGN);
  50
  51   unlink(name);
  52   mkfifo(name, S_IRWXU);
  53   semaphore s1, s2;
  54
  55   int child = fork();
  56   VERIFY( child != -1 );
  57
  58   if (child == 0)
  59     {
  60       FILE* file = fopen(name, "r+");
  61       VERIFY( file != 0 );
  62       fputs("Whatever\n", file);
  63       fflush(file);
  64       s1.signal();
  65       s2.wait();
  66       fclose(file);
  67       s1.signal();
  68       exit(0);
  69     }
  70
  71   VERIFY( freopen(name, "r", stdin) );
  72   s1.wait();
  73
  74   int c1 = fgetc(stdin);
  75   VERIFY( c1 != EOF );
  76   int c2 = cin.rdbuf()->sputbackc('a');
  77   VERIFY( c2 != EOF );
  78   VERIFY( c2 == 'a' );
  79
  80   int c3 = fgetc(stdin);
  81   VERIFY( c3 != EOF );
  82   VERIFY( c3 == c2 );
  83   int c4 = ungetc('b', stdin);
  84   VERIFY( c4 != EOF );
  85   VERIFY( c4 == 'b' );
  86
  87   int c5 = cin.rdbuf()->sgetc();
  88   VERIFY( c5 != EOF );
  89   VERIFY( c5 == c4 );
  90   s2.signal();
  91   s1.wait();
  92
  93   return test;
  94 }
  95
  96 int main()
  97 {
  98   return !test01();
  99 }