Use custom shutdown program to safely shutdown

.gitignore

@@ -5,3 +5,4 @@ tmp/
 
 rootfs
 rootfs_mnt/
+shutdown/shutdown

README.md

@@ -59,6 +59,14 @@ $ make install
 $ popd
 ```
 
+# Shutdown and Reboot utilities
+
+``` shellsession
+$ pushd shutdown
+$ gcc -static shutdown.c -o shutdown
+$ popd
+```
+
 # Finishing steps
 
 ``` shellsession

make_emacs_rootfs.sh

@@ -12,7 +12,7 @@ mke2fs $ROOTFS
 mkdir -p $ROOTFS_MNT
 sudo mount -o loop $ROOTFS $ROOTFS_MNT
 
-rfs_mkdir bin/ boot/ dev/ etc/ lib/ proc/ run/ sbin/ tmp/
+rfs_mkdir bin/ boot/ dev/ etc/ lib/ proc/ run/ sbin/ sys/ tmp/
 sudo ln -s . "$ROOTFS_MNT/usr"
 sudo mknod -m 600 "$ROOTFS_MNT/dev/console" c 5 1
 sudo mknod -m 666 "$ROOTFS_MNT/dev/null" c 1 3

setup_emacs_rootfs.sh

@@ -8,3 +8,6 @@ sudo ln "$ROOTFS_MNT/bin/busybox" "$ROOTFS_MNT/sbin/getty"
 sudo ln -s ../bin/busybox "$ROOTFS_MNT/sbin/mount"
 sudo ln -s ../bin/busybox "$ROOTFS_MNT/sbin/umount"
 sudo cp -r ncurses/build/share/terminfo/ "$ROOTFS_MNT/share/"
+sudo cp -r .emacs.d "$ROOTFS_MNT/"
+sudo cp shutdown/shutdown "$ROOTFS_MNT/sbin/shutdown"
+sudo ln -s shutdown "$ROOTFS_MNT/sbin/reboot"

shutdown/shutdown.c

@@ -0,0 +1,14 @@
+#include <sys/reboot.h>
+#include <string.h>
+#include <stdio.h>
+
+int main(int argc, char* argv[]) {
+  if (strcmp(argv[0], "/sbin/shutdown") == 0) {
+    reboot(RB_POWER_OFF);
+    return 0;
+  } else if (strcmp(argv[0], "/sbin/reboot") == 0) {
+    reboot(RB_AUTOBOOT);
+    return 0;
+  }
+  return 1;
+}