Use presence of token file during termination

When the token file is present, remove through creating a termination
file. Otherwise, kill the entire process tree directly, as the runner
has not (yet) been registered at GitHub.

lib/common.sh

@@ -122,7 +122,7 @@ kill_tree() {
   verbose "Killing process tree for $1"
   for pid in $(ps_tree "$1"|tac); do
     debug "Killing process $pid"
-    kill -s "${2:-TERM}" -- "$pid"
+    kill -s "${2:-TERM}" -- "$pid" 2>/dev/null
   done
 }
 

runner.sh

@@ -285,13 +285,24 @@ vm_delete() {
 }
 
 vm_terminate() {
-  if [ -n "$RUNNER_ENVIRONMENT" ] && [ -n "${RUNNER_SECRET:-}" ]; then
-    printf %s\\n "$RUNNER_SECRET" > "${RUNNER_ENVIRONMENT}/${RUNNER_ID}.trm"
-    if [ "$RUNNER_PID" ]; then
+  if [ -n "$RUNNER_ENVIRONMENT" ]; then
+    if [ -f "${RUNNER_ENVIRONMENT}/${RUNNER_ID}.tkn" ]; then
+      if [ -n "${RUNNER_SECRET:-}" ]; then
+        verbose "Requesting termination via ${RUNNER_ENVIRONMENT}/${RUNNER_ID}.trm"
+        printf %s\\n "$RUNNER_SECRET" > "${RUNNER_ENVIRONMENT}/${RUNNER_ID}.trm"
+      elif [ -n "$RUNNER_PID" ]; then
+        kill_tree "$RUNNER_PID"
+      fi
+      if [ "$RUNNER_PID" ]; then
+        # shellcheck disable=SC2046 # We want to wait for all children
+        waitpid $(ps_tree "$RUNNER_PID"|tac)
+      else
+        warning "No PID to wait for"
+      fi
+    elif [ -n "$RUNNER_PID" ]; then
+      kill_tree "$RUNNER_PID"
       # shellcheck disable=SC2046 # We want to wait for all children
       waitpid $(ps_tree "$RUNNER_PID"|tac)
-    else
-      warning "No PID to wait for"
     fi
   elif [ -n "$RUNNER_PID" ]; then
     kill_tree "$RUNNER_PID"