+static void
+vcl_cleanup_forked_child (vcl_worker_t * wrk, vcl_worker_t * child_wrk)
+{
+ vcl_worker_t *sub_child;
+ int tries = 0;
+
+ if (child_wrk->forked_child != ~0)
+ {
+ sub_child = vcl_worker_get_if_valid (child_wrk->forked_child);
+ if (sub_child)
+ {
+ /* Wait a bit, maybe the process is going away */
+ while (kill (sub_child->current_pid, 0) >= 0 && tries++ < 50)
+ usleep (1e3);
+ if (kill (sub_child->current_pid, 0) < 0)
+ vcl_cleanup_forked_child (child_wrk, sub_child);
+ }
+ }
+ vcl_worker_cleanup (child_wrk, 1 /* notify vpp */ );
+ VDBG (0, "Cleaned up wrk %u", child_wrk->wrk_index);
+ wrk->forked_child = ~0;
+}
+
+static struct sigaction old_sa;
+
+static void
+vcl_intercept_sigchld_handler (int signum, siginfo_t * si, void *uc)
+{
+ vcl_worker_t *wrk, *child_wrk;
+
+ if (vcl_get_worker_index () == ~0)
+ return;
+
+ if (sigaction (SIGCHLD, &old_sa, 0))
+ {
+ VERR ("couldn't restore sigchld");
+ exit (-1);
+ }
+
+ wrk = vcl_worker_get_current ();
+ if (wrk->forked_child == ~0)
+ return;
+
+ child_wrk = vcl_worker_get_if_valid (wrk->forked_child);
+ if (!child_wrk)
+ goto done;
+
+ if (si && si->si_pid != child_wrk->current_pid)
+ {
+ VDBG (0, "unexpected child pid %u", si->si_pid);
+ goto done;
+ }
+ vcl_cleanup_forked_child (wrk, child_wrk);
+
+done:
+ if (old_sa.sa_flags & SA_SIGINFO)
+ {
+ void (*fn) (int, siginfo_t *, void *) = old_sa.sa_sigaction;
+ fn (signum, si, uc);
+ }
+ else
+ {
+ void (*fn) (int) = old_sa.sa_handler;
+ if (fn)
+ fn (signum);
+ }
+}
+
+static void
+vcl_incercept_sigchld ()
+{
+ struct sigaction sa;
+ clib_memset (&sa, 0, sizeof (sa));
+ sa.sa_sigaction = vcl_intercept_sigchld_handler;
+ sa.sa_flags = SA_SIGINFO;
+ if (sigaction (SIGCHLD, &sa, &old_sa))
+ {
+ VERR ("couldn't intercept sigchld");
+ exit (-1);
+ }
+}
+
+static void
+vcl_app_pre_fork (void)
+{
+ vcl_incercept_sigchld ();
+}
+
+static void