misc/tst-pselect.c

   1 #include <errno.h>
   2 #include <signal.h>
   3 #include <stdio.h>
   4 #include <unistd.h>
   5 #include <sys/select.h>
   6 #include <sys/wait.h>
   7 #include <stdlib.h>
   8
   9
  10 static volatile int handler_called;
  11
  12 static void
  13 handler (int sig)
  14 {
  15   handler_called = 1;
  16 }
  17
  18
  19 static int
  20 do_test (void)
  21 {
  22   struct sigaction sa;
  23   sa.sa_handler = handler;
  24   sa.sa_flags = 0;
  25   sigemptyset (&sa.sa_mask);
  26
  27   if (sigaction (SIGUSR1, &sa, NULL) != 0)
  28     {
  29       puts ("sigaction failed");
  30       return 1;
  31     }
  32
  33   sa.sa_handler = SIG_IGN;
  34   if (sigaction (SIGCHLD, &sa, NULL) != 0)
  35     {
  36       puts ("2nd sigaction failed");
  37       return 1;
  38     }
  39
  40   sigset_t ss_usr1;
  41   sigemptyset (&ss_usr1);
  42   sigaddset (&ss_usr1, SIGUSR1);
  43   if (sigprocmask (SIG_BLOCK, &ss_usr1, NULL) != 0)
  44     {
  45       puts ("sigprocmask failed");
  46       return 1;
  47     }
  48
  49   int fds[2][2];
  50
  51   if (pipe (fds[0]) != 0 || pipe (fds[1]) != 0)
  52     {
  53       puts ("pipe failed");
  54       return 1;
  55     }
  56
  57   fd_set rfds;
  58   FD_ZERO (&rfds);
  59
  60   sigset_t ss;
  61   sigprocmask (SIG_SETMASK, NULL, &ss);
  62   sigdelset (&ss, SIGUSR1);
  63
  64   struct timespec to = { .tv_sec = 0, .tv_nsec = 500000000 };
  65
  66   pid_t parent = getpid ();
  67   pid_t p = fork ();
  68   if (p == 0)
  69     {
  70       close (fds[0][1]);
  71       close (fds[1][0]);
  72
  73       FD_SET (fds[0][0], &rfds);
  74
  75       int e;
  76       do
  77         {
  78           if (getppid () != parent)
  79             exit (2);
  80
  81           errno = 0;
  82           e = pselect (fds[0][0] + 1, &rfds, NULL, NULL, &to, &ss);
  83         }
  84       while (e == 0);
  85
  86       if (e != -1)
  87         {
  88           puts ("child: pselect did not fail");
  89           return 0;
  90         }
  91       if (errno != EINTR)
  92         {
  93           puts ("child: pselect did not set errno to EINTR");
  94           return 0;
  95         }
  96
  97       TEMP_FAILURE_RETRY (write (fds[1][1], "foo", 3));
  98
  99       exit (0);
 100     }
 101
 102   close (fds[0][0]);
 103   close (fds[1][1]);
 104
 105   FD_SET (fds[1][0], &rfds);
 106
 107   kill (p, SIGUSR1);
 108
 109   int e = pselect (fds[1][0] + 1, &rfds, NULL, NULL, NULL, &ss);
 110   if (e == -1)
 111     {
 112       puts ("parent: pselect failed");
 113       return 1;
 114     }
 115   if (e != 1)
 116     {
 117       puts ("parent: pselect did not report readable fd");
 118       return 1;
 119     }
 120   if (!FD_ISSET (fds[1][0], &rfds))
 121     {
 122       puts ("parent: pselect reports wrong fd");
 123       return 1;
 124     }
 125
 126   return 0;
 127 }
 128
 129 #define TEST_FUNCTION do_test ()
 130 #include "../test-skeleton.c"