Report a non-zero exit status if after forking, the child encounters an error during...

diff --git a/src/main/radiusd.c b/src/main/radiusd.c
index 71980bb..96a3f62 100644 (file)
--- a/src/main/radiusd.c
+++ b/src/main/radiusd.c
@@ -97,6 +97,7 @@ int main(int argc, char *argv[])
        int spawn_flag = TRUE;
        int dont_fork = FALSE;
        int flag = 0;
+       int from_child[2] = {-1, -1};
 
 #ifdef HAVE_SIGACTION
        struct sigaction act;
@@ -286,12 +287,45 @@ int main(int argc, char *argv[])
                        exit(1);
                }
 
+               pid = fork();
+               if (pid < 0) {
+                       radlog(L_ERR, "Couldn't fork: %s", strerror(errno));
+                       exit(1);
+               }
+
                /*
                 *  The parent exits, so the child can run in the background.
+                *
+                *  As the child can still encounter an error during initialisation
+                *  we do a blocking read on a pipe between it and the parent.
+                *
+                *  Just before entering the event loop the child will
                 */
                if (pid > 0) {
+                       uint8_t ret = 0;
+                       int stat_loc;
+
+                       /* So the pipe is correctly widowed if the child exits */
+                       close(from_child[1]);
+
+                       if ((read(from_child[0], &ret, 1) < 0)) {
+                               ret = 0;
+                       }
+
+                       /* For cleanliness... */
+                       close(from_child[0]);
+
+                       /* Don't turn children into zombies */
+                       if (!ret) {
+                               waitpid(pid, &stat_loc, WNOHANG);
+                               exit(1);
+                       }
+
                        exit(0);
                }
+
+               /* so the pipe is correctly widowed if the parent exits?! */
+               close(from_child[0]);
 #ifdef HAVE_SETSID
                setsid();
 #endif
@@ -414,6 +448,14 @@ int main(int argc, char *argv[])
                               mainconfig.pid_file, strerror(errno));
                        exit(1);
                }
+
+               /*
+                *      Inform parent (who should still be waiting) that
+                *      the rest of initialisation went OK, and that it
+                *      should exit with a 0 status.
+                */
+               write(from_child[1], "\001", 1);
+               close(from_child[1]);
        }
 
        /*