[src/trunk]: src/sbin/init Allow getty to exit quickly a few times before dec...

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2fc6f8cb7246
branches:  trunk
changeset: 989105:2fc6f8cb7246
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Mon Oct 11 20:23:25 2021 +0000

description:
Allow getty to exit quickly a few times before deciding that it is exiting
too quickly. Based on a FreeBSD change from 1994.

diffstat:

 sbin/init/init.c |  22 ++++++++++++++++++----
 1 files changed, 18 insertions(+), 4 deletions(-)

diffs (71 lines):

diff -r cad51e967a58 -r 2fc6f8cb7246 sbin/init/init.c
--- a/sbin/init/init.c  Mon Oct 11 20:13:46 2021 +0000
+++ b/sbin/init/init.c  Mon Oct 11 20:23:25 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.108 2020/06/22 07:50:53 msaitoh Exp $       */
+/*     $NetBSD: init.c,v 1.109 2021/10/11 20:23:25 jmcneill Exp $      */
 
 /*-
  * Copyright (c) 1991, 1993
@@ -42,7 +42,7 @@
 #if 0
 static char sccsid[] = "@(#)init.c     8.2 (Berkeley) 4/28/95";
 #else
-__RCSID("$NetBSD: init.c,v 1.108 2020/06/22 07:50:53 msaitoh Exp $");
+__RCSID("$NetBSD: init.c,v 1.109 2021/10/11 20:23:25 jmcneill Exp $");
 #endif
 #endif /* not lint */
 
@@ -91,6 +91,7 @@
  */
 #define        GETTY_SPACING            5      /* N secs minimum getty spacing */
 #define        GETTY_SLEEP             30      /* sleep N secs after spacing problem */
+#define        GETTY_NSPACE             5      /* N retries before spacing problem */
 #define        WINDOW_WAIT              3      /* wait N secs after starting window */
 #define        STALL_TIMEOUT           30      /* wait N secs after warning */
 #define        DEATH_WATCH             10      /* wait N secs for procs to die */
@@ -151,6 +152,7 @@
        int     se_index;               /* index of entry in ttys file */
        pid_t   se_process;             /* controlling process */
        struct timeval  se_started;     /* used to avoid thrashing */
+       int     se_nspace;              /* spacing count */
        int     se_flags;               /* status of session */
 #define        SE_SHUTDOWN     0x1             /* session won't be restarted */
 #define        SE_PRESENT      0x2             /* session is in /etc/ttys */
@@ -1270,6 +1272,17 @@
        pid_t pid;
        sigset_t mask;
        time_t current_time = time(NULL);
+       bool do_sleep = false;
+
+       if (current_time >= sp->se_started.tv_sec &&
+           current_time - sp->se_started.tv_sec < GETTY_SPACING) {
+               if (++sp->se_nspace > GETTY_NSPACE) {
+                       sp->se_nspace = 0;
+                       do_sleep = true;
+               }
+       } else {
+               sp->se_nspace = 0;
+       }
 
        /*
         * fork(), not vfork() -- we can't afford to block.
@@ -1293,8 +1306,7 @@
                }
 #endif /* CHROOT */
 
-       if (current_time > sp->se_started.tv_sec &&
-           current_time - sp->se_started.tv_sec < GETTY_SPACING) {
+       if (do_sleep) {
                warning("getty repeating too quickly on port `%s', sleeping",
                    sp->se_device);
                (void)sleep(GETTY_SLEEP);
@@ -1555,6 +1567,8 @@
                                sp->se_flags |= SE_SHUTDOWN;
                                if (sp->se_process != 0)
                                        (void)kill(sp->se_process, SIGHUP);
+                       } else {
+                               sp->se_nspace = 0;
                        }
                        continue;
                }