Update.

diff --git a/rsync-luks.sh b/rsync-luks.sh
index 1b244c2..672890b 100755 (executable)
--- a/rsync-luks.sh
+++ b/rsync-luks.sh
@@ -20,7 +20,7 @@
 set -e
 set -o pipefail
 
-if [ "$1" == "-h" ] || [ "$1" == "--help" ]; then
+if [[ "$1" == "-h" ]] || [[ "$1" == "--help" ]]; then
     cat <<EOF
 Usage: rsync-luks.sh <source file> <dest file>
 
@@ -34,21 +34,21 @@ EOF
     exit 0
 fi
 
-[ -f "$1" ] && [ -f "$2" ] || (echo "$0 <source> <dest>" >&2 && exit 1)
+[[ -f "$1" ]] && [[ -f "$2" ]] || (echo "$0 <source> <dest>" >&2 && exit 1)
 
-[ -e "/dev/mapper/crypt-src" ] && (echo "/dev/mapper/crypt-src already exists." >&2 && exit 1)
+[[ -e "/dev/mapper/crypt-src" ]] && (echo "/dev/mapper/crypt-src already exists." >&2 && exit 1)
 
-[ -e "/dev/mapper/crypt-dst" ] && (echo "/dev/mapper/crypt-dst already exists." >&2 && exit 1)
+[[ -e "/dev/mapper/crypt-dst" ]] && (echo "/dev/mapper/crypt-dst already exists." >&2 && exit 1)
 
 function exit_handler () {
 
-    [ -n "${VOL_SRC+yes}" ] && umount "${VOL_SRC}" && rmdir "${VOL_SRC}" && unset VOL_SRC
-    [ -e "/dev/mapper/crypt-src" ] && cryptsetup luksClose crypt-src
-    [ -n "${LOOP_SRC+yes}" ] && losetup -d "${LOOP_SRC}" && unset LOOP_SRC
+    [[ -n "${VOL_SRC+yes}" ]] && umount "${VOL_SRC}" && rmdir "${VOL_SRC}" && unset VOL_SRC
+    [[ -e "/dev/mapper/crypt-src" ]] && cryptsetup luksClose crypt-src
+    [[ -n "${LOOP_SRC+yes}" ]] && losetup -d "${LOOP_SRC}" && unset LOOP_SRC
 
-    [ -n "${VOL_DST+yes}" ] && umount "${VOL_DST}" && rmdir "${VOL_DST}" && unset VOL_DST
-    [ -e "/dev/mapper/crypt-dst" ] && cryptsetup luksClose crypt-dst
-    [ -n "${LOOP_DST+yes}" ] && losetup -d "${LOOP_DST}" && unset LOOP_DST
+    [[ -n "${VOL_DST+yes}" ]] && umount "${VOL_DST}" && rmdir "${VOL_DST}" && unset VOL_DST
+    [[ -e "/dev/mapper/crypt-dst" ]] && cryptsetup luksClose crypt-dst
+    [[ -n "${LOOP_DST+yes}" ]] && losetup -d "${LOOP_DST}" && unset LOOP_DST
 
 }
 
@@ -61,7 +61,7 @@ LOOP_SRC="$(losetup -f)"
 losetup "${LOOP_SRC}" "$1"
 cryptsetup luksOpen "${LOOP_SRC}" crypt-src
 VOL_SRC="$(mktemp -d /tmp/sync-luks.XXXXXX)"
-mount /dev/mapper/crypt-src "${VOL_SRC}"
+mount -o ro /dev/mapper/crypt-src "${VOL_SRC}"
 
 LOOP_DST="$(losetup -f)"
 losetup "${LOOP_DST}" "$2"
@@ -85,7 +85,7 @@ echo "* Press 'y' to synchronize, anything else to cancel."
 
 read -n 1 KEY
 
-if [ "${KEY}" == "y" ]; then
+if [[ "${KEY}" == "y" ]]; then
     rsync --itemize-changes --delete --progress -axz "${VOL_SRC}/" "${VOL_DST}/"
 else
     echo "No synchronization."