external/ibm-public/postfix/dist/src/util/killme_after.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      killme_after 3
   6 /* SUMMARY
   7 /*      programmed death
   8 /* SYNOPSIS
   9 /*      #include <killme_after.h>
  10 /*
  11 /*      void    killme_after(seconds)
  12 /*      unsigned int seconds;
  13 /* DESCRIPTION
  14 /*      The killme_after() function does a best effort to terminate
  15 /*      the process after the specified time, should it still exist.
  16 /*      It is meant to be used in a signal handler, as an insurance
  17 /*      against getting stuck somewhere while preparing for exit.
  18 /* DIAGNOSTICS
  19 /*      None. This routine does a best effort, damn the torpedoes.
  20 /* LICENSE
  21 /* .ad
  22 /* .fi
  23 /*      The Secure Mailer license must be distributed with this software.
  24 /* AUTHOR(S)
  25 /*      Wietse Venema
  26 /*      IBM T.J. Watson Research
  27 /*      P.O. Box 704
  28 /*      Yorktown Heights, NY 10598, USA
  29 /*--*/
  30
  31 /* System library. */
  32
  33 #include <sys_defs.h>
  34 #include <signal.h>
  35 #include <unistd.h>
  36
  37 /* Utility library. */
  38
  39 #include <killme_after.h>
  40
  41 /* killme_after - self-assured death */
  42
  43 void    killme_after(unsigned int seconds)
  44 {
  45     struct sigaction sig_action;
  46
  47     /*
  48      * Schedule an ALARM signal, and make sure the signal will be delivered
  49      * even if we are being called from a signal handler and SIGALRM delivery
  50      * is blocked.
  51      */
  52     alarm(0);
  53     sigemptyset(&sig_action.sa_mask);
  54     sig_action.sa_flags = 0;
  55     sig_action.sa_handler = SIG_DFL;
  56     sigaction(SIGALRM, &sig_action, (struct sigaction *) 0);
  57     alarm(seconds);
  58     sigaddset(&sig_action.sa_mask, SIGALRM);
  59     sigprocmask(SIG_UNBLOCK, &sig_action.sa_mask, (sigset_t *) 0);
  60 }