Fixing support for multiple squashfs images (Closes: #696494).

diff --git a/scripts/boot/9990-misc-helpers.sh b/scripts/boot/9990-misc-helpers.sh
index 807d787..6b385cd 100755 (executable)
--- a/scripts/boot/9990-misc-helpers.sh
+++ b/scripts/boot/9990-misc-helpers.sh
@@ -1197,11 +1197,12 @@ link_files ()
 
 do_union ()
 {
-       local unionmountpoint unionrw unionro1 unionro2
+       local unionmountpoint unionrw unionro
        unionmountpoint="${1}"  # directory where the union is mounted
-       unionrw="${2}"          # branch where the union changes are stored
-       unionro1="${3}"         # first underlying read-only branch (optional)
-       unionro2="${4}"         # second underlying read-only branch (optional)
+       shift
+       unionrw="${1}"          # branch where the union changes are stored
+       shift
+       unionro="${*}"          # space separated list of read-only branches (optional)
 
        case "${UNIONTYPE}" in
                aufs)
@@ -1225,13 +1226,12 @@ do_union ()
                unionfs-fuse)
                        unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
                        unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
-                       if [ -n "${unionro1}" ]
-                       then
-                               unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
-                       fi
-                       if [ -n "${unionro2}" ]
+                       if [ -n "${unionro}" ]
                        then
-                               unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
+                               for rofs in ${unionro}
+                               do
+                                       unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
+                               done
                        fi
                        ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
                        unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
@@ -1240,21 +1240,27 @@ do_union ()
                        ;;
 
                overlayfs)
-                       # XXX: can unionro2 be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
-                       # XXX: and can unionro1 be optional? i.e. can overlayfs skip lowerdir?
-                       unionmountopts="-o noatime,lowerdir=${unionro1},upperdir=${unionrw}"
+                       # XXX: can multiple unionro be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
+                       # XXX: and can unionro be optional? i.e. can overlayfs skip lowerdir?
+                       if echo ${unionro} | grep -q " "
+                       then
+                               panic "Multiple lower filesystems are currently not supported with overlayfs (unionro = ${unionro})."
+                       elif [ -z "${unionro}"  ]
+                       then
+                               panic "Overlayfs needs at least one lower filesystem (read-only branch)."
+                       fi
+                       unionmountopts="-o noatime,lowerdir=${unionro},upperdir=${unionrw}"
                        mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
                        ;;
 
                *)
                        unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
-                       if [ -n "${unionro1}" ]
-                       then
-                               unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
-                       fi
-                       if [ -n "${unionro2}" ]
+                       if [ -n "${unionro}" ]
                        then
-                               unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
+                               for rofs in ${unionro}
+                               do
+                                       unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
+                               done
                        fi
                        mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
                        ;;
@@ -1491,15 +1497,13 @@ activate_custom_mounts ()
                        do
                                if [ -n "${rootmnt}" ]
                                then
-                                       rootfs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
+                                       fs="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
                                else
-                                       rootfs_dest_backing="${d}/${dest}"
+                                       fs="${d}/${dest}"
                                fi
-                               if [ -d "${rootfs_dest_backing}" ]
+                               if [ -d "${fs}" ]
                                then
-                                       break
-                               else
-                                       rootfs_dest_backing=""
+                                       rootfs_dest_backing="${rootfs_dest_backing} ${fs}"
                                fi
                        done
                fi