Add new option for opt-out auto update (#14)

* 📝 Update README.md

This commit is to update README.md which add new option of opt-out
update to latest version.

* 💥 add feature of disabling auto update

This commit is to support feature which opt-out auto update.

Dockerfile

@@ -9,7 +9,8 @@ ENV http_proxy="" \
     runner_name="" \
     label="" \
     group="" \
-    tls_no_verify=0
+    tls_no_verify=0 \
+    disable_auto_update=0
 
 WORKDIR /actions-runner
 

README.md

@@ -59,3 +59,10 @@ Add runner to specified self-hosted runner group. Self-hosted runner group is us
 ### tls_no_verify[Optional]
 
 Disable verify process for SSL/TLS. When Proxy server using self-signed certificate, this option is need to set "1".
+
+### disable_auto_update [Optional]
+
+Opt-out auto-update to the latest runner version. Use this option, this is need to set "0".
+actions/runner
+
+Details see [GitHub Docs (Controlling runner software updates on self-hosted runners)](https://docs.github.com/en/actions/hosting-your-own-runners/autoscaling-with-self-hosted-runners#controlling-runner-software-updates-on-self-hosted-runners)

start.sh

@@ -26,14 +26,20 @@ if [ ! -f "./.credentials" ]; then
     bash ./autoconf.sh
 fi
 
+DISABLE_UPDATE=""
+if [ "${disable_auto_update}" = "1" ]; then
+  DISABLE_UPDATE="--disableupdate"
+  echo "Opt-out auto update"
+fi
+
 shutdown_handler() {
     echo "Start shutdown process"
     ./config.sh remove --token "$TOKEN"
 }
 
-./run.sh &
+./run.sh $DISABLE_UPDATE &
 pid="$!"
-trap '"shutdown_handler $pid"' SIGTERM
+trap 'shutdown_handler' $pid 2 3 15
 while kill -0 $pid > /dev/null 2>&1; do
     wait
 done