osi-mk: fix

"Ignore space change" will be useful

1 files changed, 39 insertions, 35 deletions

diff --git a/osi-mk b/osi-mk
index 06502e9..71f7adb 100755
--- a/osi-mk
+++ b/osi-mk
@@ -177,47 +177,51 @@ main() {
 
 		# main code starts here
 		outside)
-			if $arg_edit; then
-				if [[ -n $arg_edit_base ]]; then
-					# shellcheck disable=SC2059
-					printf -v prefix "$(gettext -- '%s [format]')" "$NAME"
-					{
+			# shellcheck disable=SC2059
+			printf -v prefix "$(gettext -- '%s [format]')" "$NAME"
+			{
+				if $arg_edit; then
+					if [[ -n $arg_edit_base ]]; then
 						cp -T -- "$arg_edit_base" "$arg_file"
 						btrfstune -fu "$arg_file"
-					} |& sed "s|^|${prefix} |"
-				fi
-				if [[ -n $arg_size ]]; then
-					# Calculate sizes in exact bytes now, to avoid any discrepancies
-					# between truncate(1) and btrfs-filesystem(8).
-					tmpfile=$(mktemp -t -- "${0##*/}.XXXXXXXXXX")
-					trap "rm -- ${tmpfile@Q}" EXIT
-					truncate --reference="$arg_file" --size="$arg_size" -- "$tmpfile"
-					old_size=$(stat --format='%s' -- "$arg_file")
-					new_size=$(stat --format='%s' -- "$tmpfile")
-					rm -- "$tmpfile"
-					trap - EXIT
+					fi
+					if [[ -n $arg_size ]]; then
+						# Calculate sizes in exact bytes now, to avoid any discrepancies
+						# between truncate(1) and btrfs-filesystem(8).
+						# Use truncate(1) to do this.  It's a little gross,
+						# but because TMPDIR is likely on tmpfs, it's time-cheap,
+						# and because of sparse files, it's space-cheap.
+						tmpfile=$(mktemp -t -- "${0##*/}.XXXXXXXXXX")
+						trap "rm -- ${tmpfile@Q}" EXIT
+						case "$arg_size" in
+							'+'*|'-'*|'<'*|'>'*|'/'*|'%'*)
+								truncate --reference="$arg_file" --size="$arg_size" -- "$tmpfile";;
+							*)
+								truncate --size="$arg_size" -- "$tmpfile";;
+						esac
+						old_size=$(stat --format='%s' -- "$arg_file")
+						new_size=$(stat --format='%s' -- "$tmpfile")
+						rm -- "$tmpfile"
+						trap - EXIT
 
-					# Do the resize
-					arg_mountpoint=$(mktemp -dt -- "${0##*/}.XXXXXXXXXX")
-					trap "rmdir -- ${arg_mountpoint@Q}" EXIT
-					if (( new_size > old_size )); then
-						truncate --size="$new_size" -- "$arg_file"
-						sudo -- ./osi-mount --root -- "$arg_file" "$arg_mountpoint" btrfs filesystem resize max "$arg_mountpoint"
-					elif (( new_size < old_size )); then
-						sudo -- ./osi-mount --root -- "$arg_file" "$arg_mountpoint" btrfs filesystem resize "$new_size" "$arg_mountpoint"
-						truncate --size="$new_size" -- "$arg_file"
+						# Do the resize
+						arg_mountpoint=$(mktemp -dt -- "${0##*/}.XXXXXXXXXX")
+						trap "rmdir -- ${arg_mountpoint@Q}" EXIT
+						if (( new_size > old_size )); then
+							truncate --size="$new_size" -- "$arg_file"
+							sudo -- ./osi-mount --root -- "$arg_file" "$arg_mountpoint" btrfs filesystem resize max "$arg_mountpoint"
+						elif (( new_size < old_size )); then
+							sudo -- ./osi-mount --root -- "$arg_file" "$arg_mountpoint" btrfs filesystem resize "$new_size" "$arg_mountpoint"
+							truncate --size="$new_size" -- "$arg_file"
+						fi
+						rmdir -- "$arg_mountpoint"
+						trap - EXIT
 					fi
-					rmdir -- "$arg_mountpoint" EXIT
-					trap - EXIT
-				fi
-			else
-				# shellcheck disable=SC2059
-				printf -v prefix "$(gettext -- '%s [format]')" "$NAME"
-				{
+				else
 					truncate --size="$arg_size" -- "$arg_file"
 					mkfs.btrfs -- "$arg_file"
-				} |& sed "s|^|${prefix} |"
-			fi
+				fi
+			} |& sed "s|^|${prefix} |"
 			arg_mountpoint=$(mktemp -dt -- "${0##*/}.XXXXXXXXXX")
 			trap "rmdir -- ${arg_mountpoint@Q}" EXIT
 			sudo -- ./osi-mount --root -- "$arg_file" "$arg_mountpoint" "${BASH_SOURCE[0]}" --inside="$arg_mountpoint" "${arg_orig[@]}"