read-only-rootfs-hook.sh 968 B

1234567891011121314151617181920212223242526272829303132333435363738
  1. #!/bin/sh
  2. . /etc/default/rcS
  3. [ "$ROOTFS_READ_ONLY" = "no" ] && exit 0
  4. is_on_read_only_partition () {
  5. DIRECTORY=$1
  6. dir=`readlink -f $DIRECTORY`
  7. while true; do
  8. if [ ! -d "$dir" ]; then
  9. echo "ERROR: $dir is not a directory"
  10. exit 1
  11. else
  12. for flag in `awk -v dir=$dir '{ if ($2 == dir) { print "FOUND"; split($4,FLAGS,",") } }; \
  13. END { for (f in FLAGS) print FLAGS[f] }' < /proc/mounts`; do
  14. [ "$flag" = "FOUND" ] && partition="read-write"
  15. [ "$flag" = "ro" ] && { partition="read-only"; break; }
  16. done
  17. if [ "$dir" = "/" -o -n "$partition" ]; then
  18. break
  19. else
  20. dir=`dirname $dir`
  21. fi
  22. fi
  23. done
  24. [ "$partition" = "read-only" ] && echo "yes" || echo "no"
  25. }
  26. if [ "$1" = "start" ] ; then
  27. if [ `is_on_read_only_partition /var/lib` = "yes" ]; then
  28. grep -q "tmpfs /var/volatile" /proc/mounts || mount /var/volatile
  29. mkdir -p /var/volatile/lib
  30. cp -a /var/lib/* /var/volatile/lib
  31. mount --bind /var/volatile/lib /var/lib
  32. fi
  33. fi