jenkins-helpers.sh: Add wait_for_ssh_server.

This new helper is used by start-container-docker.sh,
and will be used by other scripts later (for instance
by benchmarking scripts, to wait until a board has
rebooted).

Change-Id: I9853a2d1c0ae67df9bb3e90b65651d050c3e35f7

1 files changed, 28 insertions, 0 deletions

diff --git a/jenkins-helpers.sh b/jenkins-helpers.sh
index c4080e7d..48d4724d 100644
--- a/jenkins-helpers.sh
+++ b/jenkins-helpers.sh
@@ -227,3 +227,31 @@ wget_wildcard_url ()
     return $count
     )
 }
+
+# Wait until the ssh server is ready to accept connexions
+# $1: host
+# $2: port
+# $3: retry count (optional)
+# Returns 0 on success, 1 in case of error
+wait_for_ssh_server ()
+{
+    local count=20
+    local session_host="$1"
+    local session_port="$2"
+
+    [ "x$3" != x ] && count="$3"
+
+    while [ $count -gt 0 ]
+    do
+	ssh -p $session_port $session_host true && break
+	echo SSH server not ready, waiting.....
+	sleep 5
+	count=$((count - 1))
+    done
+
+    if [ $count -eq 0 ]; then
+	echo "ERROR: SSH server did not respond ($session_host:$session_port)"
+	return 1
+    fi
+    return 0
+}