fix bug by completing the PR #650 (#824)

Signed-off-by: Denis barbaron <denis.barbaron@orange.com>

lib/units/api/controllers/user.js

@@ -138,6 +138,7 @@ function addUserDevice(req, res) {
 
         datautil.normalize(device, req.user)
         if (!deviceutil.isAddable(device, req.user)) {
+          lockutil.unlockDevice(lock)
           return res.status(403).json({
             success: false
           , description: 'Device is being used or not available'
@@ -147,6 +148,7 @@ function addUserDevice(req, res) {
         // Timer will be called if no JoinGroupMessage is received till 5 seconds
         var responseTimer = setTimeout(function() {
           req.options.channelRouter.removeListener(wireutil.global, messageListener)
+          lockutil.unlockDevice(lock)
           return res.status(504).json({
               success: false
             , description: 'Device is not responding'
@@ -158,6 +160,7 @@ function addUserDevice(req, res) {
             if (message.serial === serial && message.owner.email === req.user.email) {
               clearTimeout(responseTimer)
               req.options.channelRouter.removeListener(wireutil.global, messageListener)
+              lockutil.unlockDevice(lock)
 
               return res.json({
                 success: true
@@ -191,13 +194,10 @@ function addUserDevice(req, res) {
           )
         ])
       }
-      return false
     })
     .catch(function(err) {
-      apiutil.internalError(res, `Failed to take control of ${serial} device: `, err.stack)
-    })
-    .finally(function() {
       lockutil.unlockDevice(lock)
+      apiutil.internalError(res, `Failed to take control of ${serial} device: `, err.stack)
     })
 }