openwrt/package/block-extroot/files/50_determine_usb_root

#!/bin/sh
# Copyright (C) 2010 Vertical Communications
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.


determine_external_root() {
	pi_include /lib/functions/extmount.sh
	pi_include /lib/functions/mount.sh

	local OLD_UCI_CONFIG_DIR="$UCI_CONFIG_DIR"
	set_jffs_mp
	determine_root_device

	# extroot requires extroot and fstab config files, therefore 
	# we assume configuration is incomplete and not to be used if either of them
	# is missing (for jffs versions of these files on squashfs image)
	if [ "$jffs" = "/tmp/overlay" ] && [ -r "/tmp/overlay/etc/config/fstab" ]; then
		UCI_CONFIG_DIR="/tmp/overlay/etc/config"
		ER_IS_SQUASHFS=true
		ER_OVERLAY_PREFIX="/tmp/overlay"
	fi

	# For squashfs on firstboot root_device will be tmpfs for the ramoverlay,
	# unless there is a saved config, in which case it will be /dev/root,
	# however in the case of a saved config, it won't be restored until after
	# this script, so there won't be a config on the first boot after
	# flashing a squashfs-based filesystem
	# For ext2, ramdisk, or jffs2 root filesystems root_device is /dev/root
	# For squashfs after firstboot, root filesystem is /dev/root	
	# We only use the config from the root or jffs if the root_device is 
	# /dev/root
	[ "$root_device" = "/dev/root" ] && {
		er_load_modules
		[ -n "$extroot_settle_time" ] && [ "$extroot_settle_time" -gt 0 ] && {
			sleep $extroot_settle_time
		} 
		config_load fstab
		config_foreach config_mount_by_section mount 1
		ER_OVERLAY_ROM="/no-extroot"
		
		[ "$rootfs_found" = "1" ] && grep -q ' /overlay ' /proc/mounts && { 
			pi_extroot_mount_success=true
			pi_mount_skip_next=false
			ER_OVERLAY_ROM="/overlay"
		}
		[ "$rootfs_found" = "1" ] && grep -q ' /rom ' /proc/mounts && { 
			pi_extroot_mount_success=true
			pi_mount_skip_next=false
			ER_OVERLAY_ROM="/rom"
		}
	}
	UCI_CONFIG_DIR="$OLD_UCI_CONFIG_DIR"
}

boot_hook_add preinit_mount_root determine_external_root