erc: add --use-7z and --use-patool

bin/erc-sh-archive

@@ -20,15 +20,22 @@
 have_patool()
 {
 	# TODO: optimize?
-	is_command patool
+	[ -n "$use_7z" ] && return 1
+	[ -n "$use_patool" ] || is_command patool
 }
 
-HAVE_7Z=''
-if ! have_patool ; then
-	# TODO: try install patool and p7zip
-	is_command 7za && HAVE_7Z="7za"
-	is_command 7z && HAVE_7Z="7z"
-fi
+set_backend()
+{
+	HAVE_7Z='7z'
+	[ -n "$use_patool" ] && [ -n "$use_7z" ] && fatal "Don't use --use-7z and --use-tool simulateously."
+
+	if [ -n "$use_7z" ] || ! have_patool ; then
+		# TODO: try install patool and p7zip
+		is_command 7za && HAVE_7Z='7za'
+		#is_command 7z && HAVE_7Z='7z'
+	fi
+	[ -z "$force" ] || HAVE_7Z="$HAVE_7Z -y"
+}
 
 
 list_subformats()

bin/tools_erc

@@ -209,6 +209,8 @@ progname="${0##*/}"
 force=
 target=
 verbose=--verbose
+use_7z=
+use_patool=
 
 if [ -z "$" ] ; then
     echo "Etersoft archive manager version @VERSION@" >&2
@@ -232,6 +234,12 @@ case "$1" in
     -f|--force)           # HELPOPT: override target
         force=-f
         ;;
+    --use-patool)         # HELPOPT: force use patool as backend
+        use_patool=1
+        ;;
+    --use-7z)             # HELPOPT: force use 7z as backend
+        use_7z=1
+        ;;
     -*)
         fatal "Unknown option '$1'"
         ;;
@@ -242,6 +250,8 @@ esac
 shift
 done
 
+set_backend
+
 cmd="$1"
 
 eval lastarg=\${$#}