From c24fb79df547212f8958e2687c1e060168c35b6e Mon Sep 17 00:00:00 2001
From: Romain Forlot <romain.forlot@iot.bzh>
Date: Fri, 18 Jan 2019 13:37:12 +0100
Subject: Handle event in core binding

Prefers to handle the events reception by the binding, in C, rather than using
the LUA interpreter to avoid race condition on the LUA context. Because we are
waiting events in LUA context using binder call sync, when the event is received
then 2 threads operate simultaneously on LUA context, the waiting event thread and
the receiving event thread.

Bug-AGL: SPEC-2135

Change-Id: Ied0a78a61263b8fd41305969c636a491c6bb0295
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>
---
 conf.d/controller/lua.d/aft.lua | 88 +++++++++++++++++------------------------
 1 file changed, 37 insertions(+), 51 deletions(-)

(limited to 'conf.d/controller')

diff --git a/conf.d/controller/lua.d/aft.lua b/conf.d/controller/lua.d/aft.lua
index 971f8be..da51a18 100644
--- a/conf.d/controller/lua.d/aft.lua
+++ b/conf.d/controller/lua.d/aft.lua
@@ -135,55 +135,25 @@ function _AFT.triggerEvtCallback(eventName)
 	end
 end
 
-function _AFT.bindingEventHandler(eventObj, uid)
-	local eventName = nil
-	local eventListeners = nil
-	local data = nil
-
-	if uid then
-		eventName = uid
-		data = eventObj
-	elseif eventObj.event.name then
-		eventName = eventObj.event.name
-		eventListeners = eventObj.data.result
-		-- Remove from event to hold the bare event data and be able to assert it
-		eventObj.data.result = nil
-		data = eventObj.data.data
-	end
-
-	if type(_AFT.monitored_events[eventName]) == 'table' then
-		local stopSync = true
-		if eventListeners then
-			_AFT.monitored_events[eventName].eventListeners = eventListeners
+function _AFT.bindingEventHandler(eventObj)
+	local eventName = eventObj.event.name
+	if eventObj.data.result then
+		_AFT.monitored_events[eventName].eventListeners = eventObj.data.result
+	end
+
+	_AFT.incrementCount(_AFT.monitored_events[eventName])
+	_AFT.registerData(_AFT.monitored_events[eventName],
+			  eventObj.data.data)
+
+	for name,value in pairs(_AFT.monitored_events) do
+		if (_AFT.monitored_events[name].expected and
+		    _AFT.monitored_events[name].receivedCount < _AFT.monitored_events[name].expected
+		   )
+		then
+			return true
 		end
-
-		_AFT.incrementCount(_AFT.monitored_events[eventName])
-		_AFT.registerData(_AFT.monitored_events[eventName], data)
-
-		for name,value in pairs(_AFT.monitored_events) do
-			if (_AFT.monitored_events[name].expected and
-			   _AFT.monitored_events[name].receivedCount < _AFT.monitored_events[name].expected)
-			then
-				stopSync = false
-			end
-		end
-
-		if stopSync == true and _AFT.waiting == true then
-			AFB:servsync(_AFT.context, _AFT.apiname, "sync", { stop = 1 })
-			_AFT.waiting = false
-		end
-	end
-end
-
-function _evt_catcher_(source, action, eventObj)
-	local uid = AFB:getuid(source)
-	if uid == "monitor/trace" then
-		if eventObj.type == "event" then
-			_AFT.bindingEventHandler(eventObj)
-		end
-	--else
-	--	_AFT.bindingEventHandler(eventObj, uid)
 	end
+	return false
 end
 
 function _AFT.lockWait(eventName, timeout)
@@ -192,12 +162,18 @@ function _AFT.lockWait(eventName, timeout)
 		return 0
 	end
 
-	_AFT.waiting = true
 	local err,responseJ = AFB:servsync(_AFT.context, _AFT.apiname, "sync", { start = timeout})
 
-	if err then
+	if err or (not responseJ and not responseJ.response.event.name) then
 		return 0
 	end
+
+	_AFT.bindingEventHandler(responseJ.response)
+
+	if AFB:servsync(_AFT.context,  _AFT.apiname, "sync", {stop = true}) then
+		return 0
+	end
+
 	return 1
 end
 
@@ -212,10 +188,20 @@ function _AFT.lockWaitGroup(eventGroup, timeout)
 		_AFT.monitored_events[event].expected = expectedCount + _AFT.monitored_events[event].receivedCount
 	end
 
-	_AFT.waiting = true
+	local waiting = true
 	local err, responseJ = AFB:servsync(_AFT.context, _AFT.apiname, "sync", { start = timeout })
+	while waiting do
+		if err or (not responseJ and not responseJ.response.event.name) then
+			return 0
+		end
+
+		waiting = _AFT.bindingEventHandler(responseJ.response)
 
-	if err then
+		if waiting == true then
+			err, responseJ = AFB:servsync(_AFT.context, _AFT.apiname, "sync", {continue = true})
+		end
+	end
+	if AFB:servsync(_AFT.context,  _AFT.apiname, "sync", {stop = true}) then
 		return 0
 	end
 
-- 
cgit 1.2.3-korg