+
+get_custom_mounts ()
+{
+ # Side-effect: leaves $devices with live-persistence.conf mounted in /live/persistence
+ # Side-effect: prints info to file $custom_mounts
+
+ local custom_mounts=${1}
+ shift
+ local devices=${@}
+
+ local bindings="/tmp/bindings.list"
+ local links="/tmp/links.list"
+ rm -rf ${bindings} ${links} 2> /dev/null
+
+ for device in ${devices}
+ do
+ if [ ! -b "${device}" ]
+ then
+ continue
+ fi
+
+ local device_name="$(basename ${device})"
+ local backing=$(mount_persistence_media ${device})
+ if [ -z "${backing}" ]
+ then
+ continue
+ fi
+
+ local include_list="${backing}/${persistence_list}"
+ if [ ! -r "${include_list}" ]
+ then
+ continue
+ fi
+
+ if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
+ then
+ cp ${include_list} /live/persistence/${persistence_list}.${device_name}
+ fi
+
+ while read dir options # < ${include_list}
+ do
+ if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
+ then
+ # skipping empty or commented lines
+ continue
+ fi
+
+ if trim_path ${dir} | grep -q -e "^[^/]" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
+ then
+ log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" or any sub-directory therein."
+ continue
+ fi
+
+ local opt_source=""
+ local opt_link=""
+ for opt in $(echo ${options} | tr ',' ' ');
+ do
+ case "${opt}" in
+ source=*)
+ opt_source=${opt#source=}
+ ;;
+ link)
+ opt_link="yes"
+ ;;
+ union|bind)
+ ;;
+ *)
+ log_warning_msg "Skipping custom mount with unkown option: ${opt}"
+ continue 2
+ ;;
+ esac
+ done
+
+ local source="${dir}"
+ if [ -n "${opt_source}" ]
+ then
+ if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${source}" != "." ]
+ then
+ log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
+ continue
+ else
+ source="${opt_source}"
+ fi
+ fi
+
+ local full_source="$(trim_path ${backing}/${source})"
+ local full_dest="$(trim_path ${rootmnt}/${dir})"
+ if [ -n "${opt_link}" ]
+ then
+ echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
+ else
+ echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
+ fi
+ done < ${include_list}
+ done
+
+ # We sort the list according to destination so we're sure that
+ # we won't hide a previous mount. We also ignore duplicate
+ # destinations in a more or less arbitrary way.
+ [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
+
+ # After all mounts are considered we add symlinks so they
+ # won't be hidden by some mount.
+ [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
+
+ # We need to make sure that no two custom mounts have the same sources
+ # or are nested; if that is the case, too much weird stuff can happen.
+ local prev_source="impossible source" # first iteration must not match
+ local prev_dest=""
+ # This sort will ensure that a source /a comes right before a source
+ # /a/b so we only need to look at the previous source
+ sort -k2 -b ${custom_mounts} |
+ while read device source dest options
+ do
+ if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
+ then
+ panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
+ fi
+ prev_source=${source}
+ prev_dest=${dest}
+ done
+}
+
+activate_custom_mounts ()
+{
+ local custom_mounts="${1}" # the ouput from get_custom_mounts()
+ local used_devices=""
+
+ while read device source dest options # < ${custom_mounts}
+ do
+ local opt_bind="yes"
+ local opt_link=""
+ local opt_union=""
+ for opt in $(echo ${options} | tr ',' ' ');
+ do
+ case "${opt}" in
+ bind)
+ opt_bind="yes"
+ unset opt_link opt_union
+ ;;
+ link)
+ opt_link="yes"
+ unset opt_bind opt_union
+ ;;
+ union)
+ opt_union="yes"
+ unset opt_bind opt_link
+ ;;
+ esac
+ done
+
+ if [ -n "$(what_is_mounted_on "${dest}")" ]
+ then
+ if [ "${dest}" = "${rootmnt}" ]
+ then
+ umount "${dest}"
+ else
+ log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
+ continue
+ fi
+ fi
+
+ if [ ! -d "${dest}" ]
+ then
+ # create the destination and delete existing files in
+ # its path that are in the way
+ path="/"
+ for dir in $(echo ${dest} | sed -e 's|/\+| |g')
+ do
+ path=$(trim_path ${path}/${dir})
+ if [ -f ${path} ]
+ then
+ rm -f ${path}
+ fi
+ if [ ! -e ${path} ]
+ then
+ mkdir -p ${path}
+ if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
+ then
+ # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
+ # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
+ chown 1000:1000 ${path}
+ fi
+ fi
+ done
+ fi
+
+ # if ${source} doesn't exist on our persistence media
+ # we bootstrap it with $dest from the live filesystem.
+ # this both makes sense and is critical if we're
+ # dealing with /etc or other system dir.
+ if [ ! -d "${source}" ]
+ then
+ if [ -n "${PERSISTENCE_READONLY}" ]
+ then
+ continue
+ elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
+ then
+ # unions and don't need to be bootstrapped
+ # link dirs can't be bootstrapped in a sensible way
+ mkdir -p "${source}"
+ chown_ref "${dest}" "${source}"
+ chmod_ref "${dest}" "${source}"
+ elif [ -n "${opt_bind}" ]
+ then
+ # ensure that $dest is not copied *into* $source
+ mkdir -p "$(dirname ${source})"
+ cp -a "${dest}" "${source}"
+ fi
+ fi
+
+ # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
+ # ignore the loop below and set rofs_dest_backing=$dest
+ local rofs_dest_backing=""
+ if [ -n "${opt_link}"]
+ then
+ for d in /live/rofs/*
+ do
+ if [ -n "${rootmnt}" ]
+ then
+ rofs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
+ else
+ rofs_dest_backing="${d}/${dest}"
+ fi
+ if [ -d "${rofs_dest_backing}" ]
+ then
+ break
+ else
+ rofs_dest_backing=""
+ fi
+ done
+ fi
+
+ if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+ then
+ link_files ${source} ${dest} ${rootmnt}
+ elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
+ then
+ mkdir -p /live/persistence
+ local links_source=$(mktemp -d /live/persistence/links-source-XXXXXX)
+ chown_ref ${source} ${links_source}
+ chmod_ref ${source} ${links_source}
+ # We put the cow dir in the below strange place to
+ # make it absolutely certain that the link source
+ # has its own directory and isn't nested with some
+ # other custom mount (if so that mount's files would
+ # be linked, causing breakage.
+ local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
+ mkdir -p ${cow_dir}
+ chown_ref "${source}" "${cow_dir}"
+ chmod_ref "${source}" "${cow_dir}"
+ do_union ${links_source} ${cow_dir} ${source} ${rofs_dest_backing}
+ link_files ${links_source} ${dest} ${rootmnt}
+ elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+ then
+ do_union ${dest} ${source} ${rofs_dest_backing}
+ elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+ then
+ mount --bind "${source}" "${dest}"
+ elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
+ then
+ # bind-mount and union mount are handled the same
+ # in read-only mode, but note that rofs_dest_backing
+ # is non-empty (and necessary) only for unions
+ if [ -n "${rootmnt}" ]
+ then
+ local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/live/overlay/|")"
+ else
+ # This is happens if persistence is activated
+ # post boot
+ local cow_dir="/live/overlay/${dest}"
+ fi
+ if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
+ then
+ # If an earlier custom mount has files here
+ # it will "block" the current mount's files
+ # which is undesirable
+ rm -rf "${cow_dir}"
+ fi
+ mkdir -p ${cow_dir}
+ chown_ref "${source}" "${cow_dir}"
+ chmod_ref "${source}" "${cow_dir}"
+ do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
+ fi
+
+ PERSISTENCE_IS_ON="1"
+ export PERSISTENCE_IS_ON
+
+ if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
+ then
+ used_devices="${used_devices} ${device}"
+ fi
+ done < ${custom_mounts}
+
+ echo ${used_devices}
+}
+
+fix_backwards_compatibility ()
+{
+ local device=${1}
+ local dir=${2}
+ local opt=${3}
+
+ if [ -n "${PERSISTENCE_READONLY}" ]
+ then
+ return
+ fi
+
+ local backing="$(mount_persistence_media ${device})"
+ if [ -z "${backing}" ]
+ then
+ return
+ fi
+
+ local include_list="${backing}/${persistence_list}"
+ if [ ! -r "${include_list}" ]
+ then
+ echo "# persistence backwards compatibility:
+${dir} ${opt},source=." > "${include_list}"
+ fi
+}
+
+is_mountpoint ()
+{
+ directory="$1"
+
+ [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
+}