src/tests/kits/net/sock/tellwait.c

   1 /* -*- c-basic-offset: 8; -*- */
   2 #include        <signal.h>
   3 #include        "ourhdr.h"
   4
   5 static volatile sig_atomic_t    sigflag;
   6                                                                 /* set nonzero by signal handler */
   7 static sigset_t                 newmask, oldmask, zeromask;
   8
   9 static void
  10 sig_usr(int signo)      /* one signal handler for SIGUSR1 and SIGUSR2 */
  11 {
  12         sigflag = 1;
  13         return;
  14 }
  15
  16 void
  17 TELL_WAIT()
  18 {
  19         if (signal(SIGUSR1, sig_usr) == SIG_ERR)
  20                 err_sys("signal(SIGINT) error");
  21         if (signal(SIGUSR2, sig_usr) == SIG_ERR)
  22                 err_sys("signal(SIGQUIT) error");
  23
  24         sigemptyset(&zeromask);
  25
  26         sigemptyset(&newmask);
  27         sigaddset(&newmask, SIGUSR1);
  28         sigaddset(&newmask, SIGUSR2);
  29                 /* block SIGUSR1 and SIGUSR2, and save current signal mask */
  30         if (sigprocmask(SIG_BLOCK, &newmask, &oldmask) < 0)
  31                 err_sys("SIG_BLOCK error");
  32 }
  33
  34 void
  35 TELL_PARENT(pid_t pid)
  36 {
  37         kill(pid, SIGUSR2);             /* tell parent we're done */
  38 }
  39
  40 void
  41 WAIT_PARENT(void)
  42 {
  43         while (sigflag == 0)
  44                 sigsuspend(&zeromask);  /* and wait for parent */
  45
  46         sigflag = 0;
  47                         /* reset signal mask to original value */
  48         if (sigprocmask(SIG_SETMASK, &oldmask, NULL) < 0)
  49                 err_sys("SIG_SETMASK error");
  50 }
  51
  52 void
  53 TELL_CHILD(pid_t pid)
  54 {
  55         kill(pid, SIGUSR1);                     /* tell child we're done */
  56 }
  57
  58 void
  59 WAIT_CHILD(void)
  60 {
  61         while (sigflag == 0)
  62                 sigsuspend(&zeromask);  /* and wait for child */
  63
  64         sigflag = 0;
  65                         /* reset signal mask to original value */
  66         if (sigprocmask(SIG_SETMASK, &oldmask, NULL) < 0)
  67                 err_sys("SIG_SETMASK error");
  68 }