misc/tst-pselect.c

   1 /* Copyright (C) 2006-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C 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 GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <signal.h>
  20 #include <stdio.h>
  21 #include <unistd.h>
  22 #include <sys/select.h>
  23 #include <sys/wait.h>
  24 #include <stdlib.h>
  25
  26
  27 static volatile int handler_called;
  28
  29 static void
  30 handler (int sig)
  31 {
  32   handler_called = 1;
  33 }
  34
  35
  36 static int
  37 do_test (void)
  38 {
  39   struct sigaction sa;
  40   sa.sa_handler = handler;
  41   sa.sa_flags = 0;
  42   sigemptyset (&sa.sa_mask);
  43
  44   if (sigaction (SIGUSR1, &sa, NULL) != 0)
  45     {
  46       puts ("sigaction failed");
  47       return 1;
  48     }
  49
  50   sa.sa_handler = SIG_IGN;
  51   if (sigaction (SIGCHLD, &sa, NULL) != 0)
  52     {
  53       puts ("2nd sigaction failed");
  54       return 1;
  55     }
  56
  57   sigset_t ss_usr1;
  58   sigemptyset (&ss_usr1);
  59   sigaddset (&ss_usr1, SIGUSR1);
  60   if (sigprocmask (SIG_BLOCK, &ss_usr1, NULL) != 0)
  61     {
  62       puts ("sigprocmask failed");
  63       return 1;
  64     }
  65
  66   int fds[2][2];
  67
  68   if (pipe (fds[0]) != 0 || pipe (fds[1]) != 0)
  69     {
  70       puts ("pipe failed");
  71       return 1;
  72     }
  73
  74   fd_set rfds;
  75   FD_ZERO (&rfds);
  76
  77   sigset_t ss;
  78   sigprocmask (SIG_SETMASK, NULL, &ss);
  79   sigdelset (&ss, SIGUSR1);
  80
  81   struct timespec to = { .tv_sec = 0, .tv_nsec = 500000000 };
  82
  83   pid_t parent = getpid ();
  84   pid_t p = fork ();
  85   if (p == 0)
  86     {
  87       close (fds[0][1]);
  88       close (fds[1][0]);
  89
  90       FD_SET (fds[0][0], &rfds);
  91
  92       int e;
  93       do
  94         {
  95           if (getppid () != parent)
  96             exit (2);
  97
  98           errno = 0;
  99           e = pselect (fds[0][0] + 1, &rfds, NULL, NULL, &to, &ss);
 100         }
 101       while (e == 0);
 102
 103       if (e != -1)
 104         {
 105           puts ("child: pselect did not fail");
 106           return 0;
 107         }
 108       if (errno != EINTR)
 109         {
 110           puts ("child: pselect did not set errno to EINTR");
 111           return 0;
 112         }
 113
 114       TEMP_FAILURE_RETRY (write (fds[1][1], "foo", 3));
 115
 116       exit (0);
 117     }
 118
 119   close (fds[0][0]);
 120   close (fds[1][1]);
 121
 122   FD_SET (fds[1][0], &rfds);
 123
 124   kill (p, SIGUSR1);
 125
 126   int e = pselect (fds[1][0] + 1, &rfds, NULL, NULL, NULL, &ss);
 127   if (e == -1)
 128     {
 129       puts ("parent: pselect failed");
 130       return 1;
 131     }
 132   if (e != 1)
 133     {
 134       puts ("parent: pselect did not report readable fd");
 135       return 1;
 136     }
 137   if (!FD_ISSET (fds[1][0], &rfds))
 138     {
 139       puts ("parent: pselect reports wrong fd");
 140       return 1;
 141     }
 142
 143   return 0;
 144 }
 145
 146 #define TEST_FUNCTION do_test ()
 147 #include "../test-skeleton.c"