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 $er_md5sum_file)"
  14         fi
  15
  16         local er_overlay_file="/overlay/etc/extroot.md5sum"
  17
  18         local er_extroot_overlay_md5sum
  19         if [ -f "$er_overlay_file" ]; then
  20                 er_extroot_overlay_md5sum="$(cat $er_overlay_file)"
  21         fi
  22
  23         if [ -z "$er_extroot_overlay_md5sum" ]; then
  24                 cat $er_md5sum_file >$er_overlay_file
  25         elif [ "$er_extroot_overlay_md5sum" != "$er_extroot_md5sum" ]; then
  26                 pi_extroot_mount_success="false"
  27                 mkdir -p /tmp/overlay-disabled
  28                 mount --move /overlay /tmp/overlay-disabled
  29         fi
  30 }
  31
  32 set_jffs_md5sum() {
  33         # We do this anytime block-extroot exists, even on the first boot with
  34         # no extroot defined.
  35
  36         local er_md5sum_file
  37         er_md5sum_file="${ER_OVERLAY_PREFIX}/.extroot.md5sum"
  38
  39         local er_extroot_md5sum
  40         if [ -f $er_md5sum_file ]; then
  41                 er_extroot_md5sum="$(cat $er_md5sum_file)"
  42         fi
  43         if [ -z "$er_extroot_md5sum" ]; then
  44                 dd if=/dev/urandom count=32 bs=1k 2>/dev/null | md5sum | cut -f1 -d\  >$er_md5sum_file
  45         fi
  46 }
  47
  48 determine_extroot_sysupgrade() {
  49         check_skip || set_jffs_md5sum
  50
  51         check_skip || [ "$pi_extroot_mount_success" != "true" ] || {
  52                 check_set_md5sum
  53         }
  54 }
  55
  56 boot_hook_add preinit_mount_root determine_extroot_sysupgrade
  57