jenkins-helpers.sh: Rework print_host_for_node to rely only on ssh

Which gives us control over TCWG "DNS" when combined with
https://review.linaro.org/c/ci/dockerfiles/+/34893 .

Change-Id: Ia9b483f195936fa27422ecaa24a9c3d16c1b446a

1 files changed, 14 insertions, 17 deletions

diff --git a/jenkins-helpers.sh b/jenkins-helpers.sh
index f274e890..4e0ad8ff 100644
--- a/jenkins-helpers.sh
+++ b/jenkins-helpers.sh
@@ -160,30 +160,27 @@ print_hw_id_for_node ()
 }
 
 # $1: Jenkins $NODE_NAME
-# Prints DNS hostname
+# Prints SSH host
 print_host_for_node ()
 {
     (
     set -euf -o pipefail
 
-    # We first check if $1 is known by the DNS inside .tcwglab. If
-    # not, it might be an external machine for which we have
-    # configured ssh
-    local host="$1.tcwglab"
-
-    # Map tcwg-x86_64-build-* and tcwg-x86_64-dev-* to build-* and dev-*
-    case "$host" in
-	tcwg-x86_64-*) host=${host#tcwg-x86_64-} ;;
-    esac
+    local host
 
-    if ! host "$host" >& /dev/null; then
-	# No DNS entry, try to see if it is handled by our ssh config
-	if ! ssh "$1" true >& /dev/null; then
-            echo "Error: no DNS entry and no SSH configuration for $host" >&2
-            exit 1
-	else
-	    host="$1"
+    # All jenkins nodes have either <NODE> or <NODE>.tcwglab entry in
+    # .ssh/config (in dockerfiles.git/tcwg-base/tcwg-buildslave/).
+    for suffix in "" ".tcwglab"; do
+	host="$1$suffix"
+	if timeout 30s ssh "$host" true >& /dev/null; then
+	    break
 	fi
+	host=""
+    done
+
+    if [ x"$host" = x"" ]; then
+        echo "Error: print_host_for_node() cannot ssh to $1 or $1.tcwglab" >&2
+        exit 1
     fi
 
     echo "$host"