Tweak zfs options

scripts/backup-zfs-dataset.sh

@@ -1,14 +1,15 @@
 #!/bin/bash
 # Create archived backups of zfs datasets, with support for incremental backups from automated snapshots.
-# Usage: backup-zfs-dataset [OPTIONS] <dataset>
+# Usage: backup-zfs-dataset [OPTIONS] <dataset> <destination>
 
 usage() {
-    >&2 printf "Usage: %s [OPTIONS] <dataset>\n" "$0"
+    >&2 printf "Usage: %s [OPTIONS] [<dataset> <destination>]\n" "$0"
     >&2 printf "Options:\n"
     >&2 printf "\t-c  --compression-level <level>       \t Specify compression level (integer)\n"
     >&2 printf "\t-s  --dataset <dataset name>          \t Specify dataset name\n"
     >&2 printf "\t-d  --destination <path to directory> \t Specify destination\n"
     >&2 printf "\t-m  --max-size <size>                 \t Specify maximum size of archive parts\n"
+    >&2 printf "\t-f  --force                           \t Force overwriting existing backups if the backup already exists\n"
     exit "${1:-1}"
 }
 
@@ -16,40 +17,44 @@ usage() {
 
 while [[ $# -gt 0 ]]; do
     case "${1}" in
-        --compression_level | -c)
+        -c | --compression_level)
             if ! [[ "${2}" =~ -[[:digit:]] ]]; then
-                >&2 printf "Error: Invalid compression level: %s\n" "${2}"
+                >&2 printf "Error: Invalid compression level: '%s'\n" "${2}"
                 usage
             fi
             compression_level="${2}"
             shift 2
             ;;
-        --dataset | -s)
+        -s | --dataset)
             if ! [ -n "${2}" ]; then
-                >&2 printf "Error: Invalid dataset: %s\n" "${2}"
+                >&2 printf "Error: Invalid dataset: '%s'\n" "${2}"
                 usage
             fi
             dataset="${2}"
             shift 2
             ;;
-        --destination | -d)
+        -d | --destination)
             if ! [ -d "${2}" ]; then
-                >&2 printf "Error: Destination directory does not exist: %s\n" "${2}"
+                >&2 printf "Error: Specified destination does not exist: '%s'\n" "${2}"
                 usage
             fi
             destination="${2}"
             shift 2
             ;;
-        --max-size | -m)
+        -m | --max-size)
             if ! [[ "${2}" =~ [[:digit:]](K|M|G) ]]; then
-                >&2 printf "Error: Invalid maximum size: %s\n" "${2}"
+                >&2 printf "Error: Invalid maximum size: '%s'\n" "${2}"
                 usage
             fi
             max_size="${2}"
             shift 2
             ;;
+        -f | --force)
+            force_create_manual_backup=1
+            shift 1
+            ;;
         *)
-            >&2 printf "Error: Invalid option: %s\n" "${1}"
+            >&2 printf "Error: Invalid option: '%s'\n" "${1}"
             usage
             ;;
     esac
@@ -57,8 +62,14 @@ done
 
 # Check arguments.
 
-if [ -z "${dataset}" ]; then
-    >&2 printf "Error: You need to specify a dataset.\n"
+if [[ -z "${dataset:=${1}}" || -z "${destination:=${2}}" ]]; then
+    >&2 printf "Error: You need to specify a dataset and a destination.\n"
+    usage
+elif [ -z "${dataset}" ]; then
+    >&2 printf "Error: Invalid dataset: '%s'\n" "${1}"
+    usage
+elif ! [ -d "${destination}" ]; then
+    >&2 printf "Error: Specified destination does not exist: '%s'\n" "${2}"
     usage
 fi