Add in a new restart init target, triggered by SIGHUP. Patch from

Russ Dill, with adjustments by me.
 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@3896 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 32 insertions, 1 deletions

diff --git a/init/init.c b/init/init.c
index d0beb2a9a..f6108f1e8 100644
--- a/init/init.c
+++ b/init/init.c
@@ -142,7 +142,8 @@ typedef enum {
         WAIT,
         ONCE,
         CTRLALTDEL,
-        SHUTDOWN
+        SHUTDOWN,
+        RESTART
 } initActionEnum;
 
 /* A mapping between "inittab" action name strings and action type codes. */
@@ -159,6 +160,7 @@ static const struct initActionType actions[] = {
         {"once", ONCE},
         {"ctrlaltdel", CTRLALTDEL},
         {"shutdown", SHUTDOWN},
+        {"restart", RESTART},
         {0, 0}
 };
 
@@ -688,6 +690,26 @@ static void shutdown_system(void)
         }
 }
 
+static void exec_signal(int sig)
+{
+        initAction *a, *tmp;
+        for (a = initActionList; a; a = tmp) {
+                tmp = a->nextPtr;
+                if (a->action == RESTART) {
+                        shutdown_system();
+                        message(CONSOLE|LOG, "Trying to re-exec %s\n", a->process);
+                        execl(a->process, a->process, NULL);
+        
+                        message(CONSOLE|LOG, "execl of %s failed: %s\n", 
+                                a->process, sys_errlist[errno]);
+                        sync();
+                        sleep(2);
+                        init_reboot(RB_HALT_SYSTEM);
+                        loop_forever();
+                }
+        }
+}
+
 static void halt_signal(int sig)
 {
         shutdown_system();
@@ -839,6 +861,8 @@ static void parse_inittab(void)
                 /* Swapoff on halt/reboot */
                 new_initAction(SHUTDOWN, "/sbin/swapoff -a", console);
 #endif
+                /* Prepare to restart init when a HUP is received */
+                new_initAction(RESTART, "/sbin/init", console);
                 /* Askfirst shell on tty1 */
                 new_initAction(ASKFIRST, LOGIN_SHELL, console);
                 /* Askfirst shell on tty2 */
@@ -937,6 +961,12 @@ extern int init_main(int argc, char **argv)
         pid_t wpid;
         int status;
 
+
+        if (argc > 1 && !strcmp(argv[1], "-q")) {
+                kill(1, SIGHUP);
+                exit(0);
+        }
+
 #ifndef DEBUG_INIT
         /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
         if (getpid() != 1
@@ -949,6 +979,7 @@ extern int init_main(int argc, char **argv)
         }
         /* Set up sig handlers  -- be sure to
          * clear all of these in run() */
+        signal(SIGHUP, exec_signal);
         signal(SIGUSR1, halt_signal);
         signal(SIGUSR2, halt_signal);
         signal(SIGINT, ctrlaltdel_signal);