+ [ -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 persistent mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
+ fi
+ prev_source=${source}
+ prev_dest=${dest}
+ done