package/block-extroot/files/55_determine_extroot_sysupgrade

   1 #!/bin/sh
   2 # Copyright (C) 2010 Daniel Dickinson
   3 # This is free software, licensed under the GNU General Public License v2.
   4 # See /LICENSE for more information.
   5
   6
   7 check_set_md5sum() {
   8         local er_md5sum_file
   9         er_md5sum_file="${ER_OVERLAY_PREFIX}/.extroot.md5sum"
  10
  11         local er_extroot_md5sum
  12         if [ -f $md5sum_file ]; then
  13                 er_extroot_md5sum="$(cat $er_md5sum_file)"
  14         fi
  15
  16         local er_extroot_overlay_md5sum
  17         if [ -f "/overlay/etc/extroot.md5sum" ]; then
  18                 er_extroot_overlay_md5sum="$(cat /overlay/.extroot.md5sum)"
  19         fi
  20
  21         if [ -z "$er_extroot_overlay_md5sum" ]; then
  22                 cat $er_md5sum_file >/overlay/.extroot.md5sum
  23         elif [ "$er_extroot_overlay_md5sum" != "$er_extroot_md5sum" ]; then
  24                 pi_extroot_mount_success="false"
  25                 mkdir -p /tmp/overlay-disabled
  26                 mount --move /overlay /tmp/overlay-disabled
  27         fi
  28 }
  29
  30 set_jffs_md5sum() {
  31         # We do this anytime block-extroot exists, even on the first boot with
  32         # no extroot defined.
  33
  34         local er_md5sum_file
  35         er_md5sum_file="${ER_OVERLAY_PREFIX}/.extroot.md5sum"
  36
  37         local er_extroot_md5sum
  38         if [ -f $er_md5sum_file ]; then
  39                 er_extroot_md5sum="$(cat $er_md5sum_file)"
  40         fi
  41         if [ -z "$er_extroot_md5sum" ]; then
  42                 dd if=/dev/urandom count=32 bs=1k 2>/dev/null | md5sum | cut -f1 -d\  >$er_md5sum_file
  43         fi
  44 }
  45
  46 determine_extroot_sysupgrade() {
  47         check_skip || set_jffs_md5sum
  48
  49         check_skip || [ "$pi_extroot_mount_success" != "true" ] || {
  50                 check_set_md5sum
  51         }
  52 }
  53
  54 boot_hook_add preinit_mount_root determine_extroot_sysupgrade
  55