refactor: replace recursion with while loop in setdir

install.sh

@@ -100,28 +100,37 @@ gettar() {
         fi
     fi
 }
-setdir() {
+
 set_usb_dir() {
+    while true; do
         $echo "请选择安装目录"
         du -hL /mnt | awk '{print " "NR" "$2"  "$1}'
         read -p "请输入相应数字 > " num
         dir=$(du -hL /mnt | awk '{print $2}' | sed -n "$num"p)
         if [ -z "$dir" ]; then
             $echo "\033[31m输入错误！请重新设置！\033[0m"
-            set_usb_dir
+            continue
         fi
+        break 1
+    done
 }
+
 set_asus_dir() {
+    while true; do
         echo -e "请选择U盘目录"
         du -hL /tmp/mnt | awk -F/ 'NF<=4' | awk '{print " "NR" "$2"  "$1}'
         read -p "请输入相应数字 > " num
         dir=$(du -hL /tmp/mnt | awk -F/ 'NF<=4' | awk '{print $2}' | sed -n "$num"p)
         if [ ! -f "$dir/asusware.arm/etc/init.d/S50downloadmaster" ]; then
             echo -e "\033[31m未找到下载大师自启文件：$dir/asusware.arm/etc/init.d/S50downloadmaster，请检查设置！\033[0m"
-            set_asus_dir
+            continue
         fi
+        break 1
+    done
 }
+
 set_cust_dir() {
+    while true; do
         echo "-----------------------------------------------"
         echo '可用路径 剩余空间:'
         df -h | awk '{print $6,$4}' | sed 1d
@@ -129,9 +138,14 @@ setdir() {
         read -p "请输入自定义路径 > " dir
         if [ "$(dir_avail $dir)" = 0 ] || [ -n "$(echo $dir | grep -E 'tmp|opt|sys')" ]; then
             $echo "\033[31m路径错误！请重新设置！\033[0m"
-            set_cust_dir
+            continue
         fi
+        break 1
+    done
 }
+
+setdir() {
+    while true; do
         echo "-----------------------------------------------"
         $echo "\033[33m注意：安装ShellCrash至少需要预留约1MB的磁盘空间\033[0m"
         if [ -n "$systype" ]; then
@@ -228,13 +242,19 @@ setdir() {
         fi
 
         if [ ! -w $dir ]; then
-        $echo "\033[31m没有$dir目录写入权限！请重新设置！\033[0m" && sleep 1 && setdir
+            $echo "\033[31m没有$dir目录写入权限！请重新设置！\033[0m"
+            sleep 1
         else
             $echo "目标目录\033[32m$dir\033[0m空间剩余：$(dir_avail $dir -h)"
             read -p "确认安装？(1/0) > " res
-        [ "$res" = "1" ] && CRASHDIR=$dir/ShellCrash || setdir
+            if [ "$res" = "1" ]; then
+                CRASHDIR=$dir/ShellCrash
+                break
             fi
+        fi
+    done
 }
+
 install() {
     echo "-----------------------------------------------"
     echo 开始从服务器获取安装文件！