fix: Do not set computername if not explictly provided (#1922)

docs/environment.md

@@ -12,7 +12,7 @@ An empty default means the variable is unset and its value is determined automat
 | `EDITION` |  | Windows edition to install, such as `core` for Windows Server Core. |
 | `LANGUAGE` | `en-US` | Windows display language, such as `English`, `en-US`, or `en`. |
 | `KEY` |  | Windows product key used to install and activate Windows. |
-| `REGION` |  | Windows regional format. Uses `LANGUAGE` when unset. |
+| `REGION` |  | Regional format. Uses `LANGUAGE` when unset. |
 | `KEYBOARD` |  | Keyboard layout. Uses `LANGUAGE` when unset. |
 | `USERNAME` | `Docker` | Name of the Windows user account. |
 | `PASSWORD` | `admin` | Password for the Windows account. |
@@ -55,14 +55,14 @@ An empty default means the variable is unset and its value is determined automat
 | Variable | Default | Description |
 |---|---|---|
 | `NETWORK` |  | Network mode, such as `nat`, `user`, or `N` to disable networking. |
-| `DHCP` | `N` | Enables macvtap networking so Windows receives an address from the external LAN through DHCP. |
+| `DHCP` | `N` | Enables macvtap networking so Windows receives a DHCP address. |
-| `HOST` | `Windows` | Computer name assigned to Windows and advertised on the network. |
+| `HOST` |  | Optional Windows computer name and advertised network hostname. |
 | `IP` |  | Overrides the automatically selected guest IPv4 address. |
 | `MAC` |  | Guest network adapter MAC address. |
 | `ADAPTER` | `virtio-net-pci` | QEMU network adapter model. |
 | `DEV` | `eth0` | Container network interface used as the uplink. |
 | `MTU` |  | MTU assigned to the guest network interface. |
-| `MASK` | `255.255.255.0` | IPv4 netmask. |
+| `MASK` | `255.255.255.0` | IPv4 netmask for guest network. |
 | `TAP` | `qemu` | TAP or macvtap interface name. |
 | `BRIDGE` | `docker` | Bridge name used for NAT networking. |
 | `HOST_PORTS` |  | Ports excluded from guest forwarding. |

src/define.sh

@@ -1338,10 +1338,7 @@ validateComputerName() {
 
   local value="$1"
 
-  if [ -z "$value" ]; then
+  [ -z "$value" ] && return 0
-    value="$APP"
-    HOST="$value"
-  fi
 
   if [ "${#value}" -gt 15 ]; then
     error "The HOST variable cannot contain more than 15 characters!"
@@ -1764,13 +1761,14 @@ prepareInstall() {
   local username="${USERNAME:-Docker}"
   local password="${PASSWORD:-admin}"
   local workgroup="${WORKGROUP:-WORKGROUP}"
+
   local sifHost sifUsername sifPassword sifOrganization sifWorkgroup
   local regUsername regPassword
 
   validateLegacyUsername "$username" "$desc" || return 1
   validatePassword "$password" "$desc" || return 1
 
-  sifHost=$(escapeSIFValue "$HOST") || return 1
+  sifHost=$(escapeSIFValue "${HOST:-*}") || return 1
   sifUsername=$(escapeSIFValue "$username") || return 1
   sifPassword=$(escapeSIFValue "$password") || return 1
   sifOrganization=$(escapeSIFValue "$APP for $ENGINE") || return 1

src/install.sh

@@ -1184,9 +1184,9 @@ updateXML() {
 
   local asset="$1"
   local language="$2"
-  local app value culture region keyboard edition key
+  local app value culture region keyboard edition
   local user user_xml auth_user admin pass pw
-  local domain qualifier host workgroup
+  local domain qualifier host workgroup key
 
   [ -z "$WIDTH" ] && WIDTH="1280"
   [ -z "$HEIGHT" ] && HEIGHT="720"
@@ -1199,10 +1199,8 @@ updateXML() {
   validatePassword "$PASSWORD" || return 1
 
   app=$(escapeXMLSed "$APP for $ENGINE") || return 1
-  host=$(escapeXMLSed "$HOST") || return 1
 
   sed -i "s|>Windows for Docker<|>$app<|g" "$asset" || return 1
-  sed -i -E "s|<ComputerName>[^<]*</ComputerName>|<ComputerName>$host</ComputerName>|g" "$asset" || return 1
   sed -i -E "s|<VerticalResolution>[^<]*</VerticalResolution>|<VerticalResolution>$HEIGHT</VerticalResolution>|g" "$asset" || return 1
   sed -i -E "s|<HorizontalResolution>[^<]*</HorizontalResolution>|<HorizontalResolution>$WIDTH</HorizontalResolution>|g" "$asset" || return 1
 
@@ -1231,6 +1229,11 @@ updateXML() {
     sed -i "s|<InputLocale>0409:00000409</InputLocale>|<InputLocale>$value</InputLocale>|g" "$asset" || return 1
   fi
 
+  if [ -n "$HOST" ]; then
+    host=$(escapeXMLSed "$HOST") || return 1
+    sed -i -E "s|<ComputerName>[^<]*</ComputerName>|<ComputerName>$host</ComputerName>|g" "$asset" || return 1
+  fi
+
   domain="$DOMAIN"
   workgroup="$WORKGROUP"