Using 'local' in a safe way.
[live-boot-grml.git] / scripts / boot / 9990-misc-helpers.sh
index 94c48e6..35448b9 100755 (executable)
@@ -65,7 +65,8 @@ get_backing_device ()
 match_files_in_dir ()
 {
        # Does any files match pattern ${1} ?
-       local pattern="${1}"
+       local pattern
+       pattern="${1}"
 
        if [ "$(echo ${pattern})" != "${pattern}" ]
        then
@@ -378,24 +379,27 @@ really_export ()
 
 is_in_list_separator_helper ()
 {
-       local sep=${1}
+       local sep element list
+       sep=${1}
        shift
-       local element=${1}
+       element=${1}
        shift
-       local list=${*}
+       list=${*}
        echo ${list} | grep -qe "^\(.*${sep}\)\?${element}\(${sep}.*\)\?$"
 }
 
 is_in_space_sep_list ()
 {
-       local element=${1}
+       local element
+       element=${1}
        shift
        is_in_list_separator_helper "[[:space:]]" "${element}" "${*}"
 }
 
 is_in_comma_sep_list ()
 {
-       local element=${1}
+       local element
+       element=${1}
        shift
        is_in_list_separator_helper "," "${element}" "${*}"
 }
@@ -512,25 +516,28 @@ trim_path ()
 
 what_is_mounted_on ()
 {
-       local dir="$(trim_path ${1})"
+       local dir
+       dir="$(trim_path ${1})"
        grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 }
 
 chown_ref ()
 {
-       local reference="${1}"
+       local reference targets owner
+       reference="${1}"
        shift
-       local targets=${@}
-       local owner=$(stat -c %u:%g "${reference}")
+       targets=${@}
+       owner=$(stat -c %u:%g "${reference}")
        chown -h ${owner} ${targets}
 }
 
 chmod_ref ()
 {
-       local reference="${1}"
+       local reference targets rights
+       reference="${1}"
        shift
-       local targets=${@}
-       local rights=$(stat -c %a "${reference}")
+       targets=${@}
+       rights=$(stat -c %a "${reference}")
        chmod ${rights} ${targets}
 }
 
@@ -616,12 +623,13 @@ load_keymap ()
 
 setup_loop ()
 {
-       local fspath=${1}
-       local module=${2}
-       local pattern=${3}
-       local offset=${4}
-       local encryption=${5}
-       local readonly=${6}
+       local fspath module pattern offset encryption readonly
+       fspath=${1}
+       module=${2}
+       pattern=${3}
+       offset=${4}
+       encryption=${5}
+       readonly=${6}
 
        # the output of setup_loop is evaluated in other functions,
        # modprobe leaks kernel options like "libata.dma=0"
@@ -730,17 +738,18 @@ try_mount ()
 # success, print the mount point for $device.
 mount_persistence_media ()
 {
-       local device=${1}
-       local probe=${2}
+       local device probe backing old_backing fstype mount_opts
+       device=${1}
+       probe=${2}
 
-       local backing="${rootmnt}/lib/live/mount/persistence/$(basename ${device})"
+       backing="${rootmnt}/lib/live/mount/persistence/$(basename ${device})"
 
        mkdir -p "${backing}"
-       local old_backing="$(where_is_mounted ${device})"
+       old_backing="$(where_is_mounted ${device})"
        if [ -z "${old_backing}" ]
        then
-               local fstype="$(get_fstype ${device})"
-               local mount_opts="rw,noatime"
+               fstype="$(get_fstype ${device})"
+               mount_opts="rw,noatime"
                if [ -n "${PERSISTENCE_READONLY}" ]
                then
                        mount_opts="ro,noatime"
@@ -775,8 +784,9 @@ mount_persistence_media ()
 
 close_persistence_media ()
 {
-       local device=${1}
-       local backing="$(where_is_mounted ${device})"
+       local device backing
+       device=${1}
+       backing="$(where_is_mounted ${device})"
 
        if [ -d "${backing}" ]
        then
@@ -842,22 +852,25 @@ open_luks_device ()
 
 get_gpt_name ()
 {
-    local dev="${1}"
+    local dev
+    dev="${1}"
     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 }
 
 is_gpt_device ()
 {
-    local dev="${1}"
+    local dev
+    dev="${1}"
     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 }
 
 probe_for_gpt_name ()
 {
-       local overlays="${1}"
-       local dev="${2}"
+       local overlays dev gpt_dev gpt_name
+       overlays="${1}"
+       dev="${2}"
 
-       local gpt_dev="${dev}"
+       gpt_dev="${dev}"
        if is_active_luks_mapping ${dev}
        then
                # if $dev is an opened luks device, we need to check
@@ -870,7 +883,7 @@ probe_for_gpt_name ()
                return
        fi
 
-       local gpt_name=$(get_gpt_name ${gpt_dev})
+       gpt_name=$(get_gpt_name ${gpt_dev})
        for label in ${overlays}
        do
                if [ "${gpt_name}" = "${label}" ]
@@ -882,8 +895,9 @@ probe_for_gpt_name ()
 
 probe_for_fs_label ()
 {
-       local overlays="${1}"
-       local dev="${2}"
+       local overlays dev
+       overlays="${1}"
+       dev="${2}"
 
        for label in ${overlays}
        do
@@ -896,11 +910,12 @@ probe_for_fs_label ()
 
 probe_for_file_name ()
 {
-       local overlays="${1}"
-       local dev="${2}"
+       local overlays dev ret backing
+       overlays="${1}"
+       dev="${2}"
 
-       local ret=""
-       local backing="$(mount_persistence_media ${dev} probe)"
+       ret=""
+       backing="$(mount_persistence_media ${dev} probe)"
        if [ -z "${backing}" ]
        then
            return
@@ -911,7 +926,8 @@ probe_for_file_name ()
                path=${backing}/${PERSISTENCE_PATH}${label}
                if [ -f "${path}" ]
                then
-                       local loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
+                       local loopdev
+                       loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
                        ret="${ret} ${label}=${loopdev}"
                fi
        done
@@ -945,17 +961,19 @@ find_persistence_media ()
        # ${white_list_devices} is non-empty, only devices in it will be
        # scanned.
 
-       local overlays="${1}"
-       local white_listed_devices="${2}"
-       local ret=""
+       local overlays white_listed_devices ret black_listed_devices
+       overlays="${1}"
+       white_listed_devices="${2}"
+       ret=""
 
-       local black_listed_devices="$(what_is_mounted_on ${rootmnt}/lib/live/medium)"
+       black_listed_devices="$(what_is_mounted_on ${rootmnt}/lib/live/medium)"
 
        for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
        do
-               local result=""
+               local result luks_device
+               result=""
 
-               local luks_device=""
+               luks_device=""
                # Check if it's a luks device; we'll have to open the device
                # in order to probe any filesystem it contains, like we do
                # below. activate_custom_mounts() also depends on that any luks
@@ -1131,11 +1149,12 @@ link_files ()
        # is non-empty, remove mask from all source paths when
        # creating links (will be necessary if we change root, which
        # live-boot normally does (into $rootmnt)).
+       local src_dir dest_dir src_mask
 
        # remove multiple /:s and ensure ending on /
-       local src_dir="$(trim_path ${1})/"
-       local dest_dir="$(trim_path ${2})/"
-       local src_mask="${3}"
+       src_dir="$(trim_path ${1})/"
+       dest_dir="$(trim_path ${2})/"
+       src_mask="${3}"
 
        # This check can only trigger on the inital, non-recursive call since
        # we create the destination before recursive calls
@@ -1148,7 +1167,8 @@ link_files ()
        find "${src_dir}" -mindepth 1 -maxdepth 1 | \
        while read src
        do
-               local dest="${dest_dir}$(basename "${src}")"
+               local dest final_src
+               dest="${dest_dir}$(basename "${src}")"
                if [ -d "${src}" ]
                then
                        if [ -z "$(ls -A "${src}")" ]
@@ -1163,7 +1183,7 @@ link_files ()
                        fi
                        link_files "${src}" "${dest}" "${src_mask}"
                else
-                       local final_src=${src}
+                       final_src=${src}
                        if [ -n "${src_mask}" ]
                        then
                                final_src="$(echo ${final_src} | sed "s|^${src_mask}||")"
@@ -1177,10 +1197,11 @@ link_files ()
 
 do_union ()
 {
-       local unionmountpoint="${1}"    # directory where the union is mounted
-       local unionrw="${2}"            # branch where the union changes are stored
-       local unionro1="${3}"           # first underlying read-only branch (optional)
-       local unionro2="${4}"           # second underlying read-only branch (optional)
+       local unionmountpoint unionrw unionro1 unionro2
+       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)
 
        case "${UNIONTYPE}" in
                aufs)
@@ -1245,12 +1266,13 @@ get_custom_mounts ()
        # Side-effect: leaves $devices with persistence.conf mounted in ${rootmnt}/lib/live/mount/persistence
        # Side-effect: prints info to file $custom_mounts
 
-       local custom_mounts=${1}
+       local custom_mounts devices bindings links
+       custom_mounts=${1}
        shift
-       local devices=${@}
+       devices=${@}
 
-       local bindings="/tmp/bindings.list"
-       local links="/tmp/links.list"
+       bindings="/tmp/bindings.list"
+       links="/tmp/links.list"
        rm -rf ${bindings} ${links} 2> /dev/null
 
        for device in ${devices}
@@ -1260,14 +1282,14 @@ get_custom_mounts ()
                        continue
                fi
 
-               local device_name="$(basename ${device})"
-               local backing=$(mount_persistence_media ${device})
+               local device_name backing include_list
+               device_name="$(basename ${device})"
+               backing=$(mount_persistence_media ${device})
                if [ -z "${backing}" ]
                then
                        continue
                fi
 
-               local include_list
                if [ -r "${backing}/${persistence_list}" ]
                then
                        include_list="${backing}/${persistence_list}"
@@ -1297,8 +1319,9 @@ get_custom_mounts ()
                                continue
                        fi
 
-                       local opt_source=""
-                       local opt_link=""
+                       local opt_source opt_link source full_source full_dest
+                       opt_source=""
+                       opt_link=""
                        for opt in $(echo ${options} | tr ',' ' ');
                        do
                                case "${opt}" in
@@ -1317,7 +1340,7 @@ get_custom_mounts ()
                                esac
                        done
 
-                       local source="${dir}"
+                       source="${dir}"
                        if [ -n "${opt_source}" ]
                        then
                                if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
@@ -1329,8 +1352,8 @@ get_custom_mounts ()
                                fi
                        fi
 
-                       local full_source="$(trim_path ${backing}/${source})"
-                       local full_dest="$(trim_path ${rootmnt}/${dir})"
+                       full_source="$(trim_path ${backing}/${source})"
+                       full_dest="$(trim_path ${rootmnt}/${dir})"
                        if [ -n "${opt_link}" ]
                        then
                                echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
@@ -1351,8 +1374,9 @@ get_custom_mounts ()
 
        # 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=""
+       local prev_source prev_dest
+       prev_source="impossible source" # first iteration must not match
+       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} |
@@ -1369,14 +1393,16 @@ get_custom_mounts ()
 
 activate_custom_mounts ()
 {
-       local custom_mounts="${1}" # the ouput from get_custom_mounts()
-       local used_devices=""
+       local custom_mounts used_devices
+       custom_mounts="${1}" # the ouput from get_custom_mounts()
+       used_devices=""
 
        while read device source dest options # < ${custom_mounts}
        do
-               local opt_bind="true"
-               local opt_link=""
-               local opt_union=""
+               local opt_bind opt_link opt_union
+               opt_bind="true"
+               opt_link=""
+               opt_union=""
                for opt in $(echo ${options} | tr ',' ' ');
                do
                        case "${opt}" in
@@ -1457,7 +1483,8 @@ activate_custom_mounts ()
 
                # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
                # ignore the loop below and set rootfs_dest_backing=$dest
-               local rootfs_dest_backing=""
+               local rootfs_dest_backing
+               rootfs_dest_backing=""
                if [ -n "${opt_link}"]
                then
                        for d in ${rootmnt}/lib/live/mount/rootfs/*
@@ -1477,13 +1504,14 @@ activate_custom_mounts ()
                        done
                fi
 
+               local cow_dir links_source
                if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
                then
                        link_files ${source} ${dest} ${rootmnt}
                elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
                then
                        mkdir -p ${rootmnt}/lib/live/mount/persistence
-                       local links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
+                       links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
                        chown_ref ${source} ${links_source}
                        chmod_ref ${source} ${links_source}
                        # We put the cow dir in the below strange place to
@@ -1491,7 +1519,7 @@ activate_custom_mounts ()
                        # has its own directory and isn't nested with some
                        # other custom mount (if so that mount's files would
                        # be linked, causing breakage.
-                       local cow_dir="${rootmnt}/lib/live/mount/overlay/lib/live/mount/persistence/$(basename ${links_source})"
+                       cow_dir="${rootmnt}/lib/live/mount/overlay/lib/live/mount/persistence/$(basename ${links_source})"
                        mkdir -p ${cow_dir}
                        chown_ref "${source}" "${cow_dir}"
                        chmod_ref "${source}" "${cow_dir}"
@@ -1508,7 +1536,7 @@ activate_custom_mounts ()
                        # bind-mount and union mount are handled the same
                        # in read-only mode, but note that rootfs_dest_backing
                        # is non-empty (and necessary) only for unions
-                       local cow_dir="${rootmnt}/lib/live/mount/overlay/${dest}"
+                       cow_dir="${rootmnt}/lib/live/mount/overlay/${dest}"
                        if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
                        then
                                # If an earlier custom mount has files here
@@ -1536,22 +1564,23 @@ activate_custom_mounts ()
 
 fix_backwards_compatibility ()
 {
-       local device=${1}
-       local dir=${2}
-       local opt=${3}
+       local device dir opt backing include_list
+       device=${1}
+       dir=${2}
+       opt=${3}
 
        if [ -n "${PERSISTENCE_READONLY}" ]
        then
                return
        fi
 
-       local backing="$(mount_persistence_media ${device})"
+       backing="$(mount_persistence_media ${device})"
        if [ -z "${backing}" ]
        then
                return
        fi
 
-       local include_list="${backing}/${persistence_list}"
+       include_list="${backing}/${persistence_list}"
        if [ ! -r "${include_list}" ]
        then
                echo "# persistence backwards compatibility: