Some busybox updates. You no longer _have_ to put a "-" in front of tar
options, logger is better behaved and has a "-t" option now. init now supports
the kernel chroot patch, so you can chroot to a new device and umount the old
root.
-Erik
diff --git a/init/init.c b/init/init.c
index 9134363..b0a8582 100644
--- a/init/init.c
+++ b/init/init.c
@@ -147,7 +147,9 @@
va_start(arguments, fmt);
vsnprintf(msg, sizeof(msg), fmt, arguments);
va_end(arguments);
+ openlog( "init", 0, LOG_DAEMON);
syslog(LOG_DAEMON|LOG_NOTICE, msg);
+ closelog();
}
#else
@@ -268,7 +270,7 @@
#if #cpu(sparc)
/* sparc kernel supports console=tty[ab] parameter which is also
* passed to init, so catch it here */
- else if ((s = getenv("console")) != NULL) {*/
+ else if ((s = getenv("console")) != NULL) {
/* remap tty[ab] to /dev/ttyS[01] */
if (strcmp( s, "ttya" )==0)
snprintf(console, sizeof(console)-1, "%s", SERIAL_CON0);
@@ -507,7 +509,83 @@
exit(0);
}
-#endif
+#if defined BB_FEATURE_INIT_CHROOT
+static void check_chroot(int sig)
+{
+ char *argv_init[2] = { "init", NULL, };
+ char *envp_init[3] = { "HOME=/", "TERM=linux", NULL, };
+ char rootpath[256], *tc;
+ int fd;
+
+ if ((fd = open("/proc/sys/kernel/init-chroot", O_RDONLY)) == -1) {
+ message(CONSOLE, "SIGHUP recived, but could not open proc file\r\n");
+ sleep(2);
+ return;
+ }
+ if (read(fd, rootpath, sizeof(rootpath)) == -1) {
+ message(CONSOLE, "SIGHUP recived, but could not read proc file\r\n");
+ sleep(2);
+ return;
+ }
+ close(fd);
+
+ if (rootpath[0] == '\0') {
+ message(CONSOLE, "SIGHUP recived, but new root is not valid: %s\r\n",
+ rootpath);
+ sleep(2);
+ return;
+ }
+
+ tc = strrchr(rootpath, '\n');
+ *tc = '\0';
+
+ /* Ok, making it this far means we commit */
+ message(CONSOLE, "Please stand by, changing root to `%s'.\r\n", rootpath);
+
+ /* kill all other programs first */
+ message(CONSOLE, "Sending SIGTERM to all processes.\r\n");
+ kill(-1, SIGTERM);
+ sleep(2);
+ sync();
+
+ message(CONSOLE, "Sending SIGKILL to all processes.\r\n");
+ kill(-1, SIGKILL);
+ sleep(2);
+ sync();
+
+ /* ok, we don't need /proc anymore. we also assume that the signaling
+ * process left the rest of the filesystems alone for us */
+ umount("/proc");
+
+ /* Ok, now we chroot. Hopefully we only have two things mounted, the
+ * new chroot'd mount point, and the old "/" mount. s,
+ * we go ahead and unmount the old "/". This should trigger the kernel
+ * to set things up the Right Way(tm). */
+
+ if (!chroot(rootpath))
+ umount("/dev/root");
+
+ /* If the chroot fails, we are already too far to turn back, so we
+ * continue and hope that executing init below will revive the system */
+
+ /* close all of our descriptors and open new ones */
+ close(0);
+ close(1);
+ close(2);
+ open("/dev/console", O_RDWR, 0);
+ dup(0);
+ dup(0);
+
+ message(CONSOLE, "Executing real init...\r\n");
+ /* execute init in the (hopefully) new root */
+ execve("/sbin/init",argv_init,envp_init);
+
+ message(CONSOLE, "ERROR: Could not exec new init. Hit ctrl+alt+delete to reboot.\r\n");
+ return;
+}
+#endif /* BB_FEATURE_INIT_CHROOT */
+
+#endif /* ! DEBUG_INIT */
void new_initAction (initActionEnum action,
char* process, char* cons)
@@ -516,10 +594,10 @@
/* If BusyBox detects that a serial console is in use,
* then entries containing non-empty id fields will _not_ be run.
+ * The exception to this rule is the null device.
*/
- if (secondConsole == NULL && *cons != '\0') {
+ if (secondConsole == NULL && (*cons != '\0' || strncmp(cons, "null", 4)))
return;
- }
newAction = calloc ((size_t)(1), sizeof(initAction));
if (!newAction) {
@@ -662,7 +740,7 @@
int status;
#ifndef DEBUG_INIT
- /* Expect to be PID 1 iff we are run as init (not linuxrc) */
+ /* Expect to be PID 1 if we are run as init (not linuxrc) */
if (getpid() != 1 && strstr(argv[0], "init")!=NULL ) {
usage( "init\n\nInit is the parent of all processes.\n\n"
"This version of init is designed to be run only by the kernel\n");
@@ -676,6 +754,9 @@
signal(SIGUSR2, reboot_signal);
signal(SIGINT, reboot_signal);
signal(SIGTERM, reboot_signal);
+#if defined BB_FEATURE_INIT_CHROOT
+ signal(SIGHUP, check_chroot);
+#endif
/* Turn off rebooting via CTL-ALT-DEL -- we get a
* SIGINT on CAD so we can shut things down gracefully... */