From 11e5020569efe21957c3079c20ffd5f69f514d7a Mon Sep 17 00:00:00 2001
From: José Bollo <jose.bollo@iot.bzh>
Date: Sat, 5 Jan 2019 21:22:20 +0100
Subject: Improve safety of link to event loop
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Instead of using the default one that depends on the
current thread and that might be shared with other
items, use an explicit new one running in a dedicated
thread.

Bug-AGL: SPEC-2130

Change-Id: Ie609d19157a5dcaf6e5fa3896dc91d88ba5f214a
Signed-off-by: José Bollo <jose.bollo@iot.bzh>
---
 src/libhomescreen.cpp | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/src/libhomescreen.cpp b/src/libhomescreen.cpp
index 84e3472..121def7 100644
--- a/src/libhomescreen.cpp
+++ b/src/libhomescreen.cpp
@@ -25,6 +25,7 @@
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <thread>
 
 #include <libhomescreen.hpp>
 #include "hmi-debug.h"
@@ -87,6 +88,12 @@ static void _on_reply_static(void *closure, struct afb_wsj1_msg *msg)
 }
 
 
+static void event_loop_run(struct sd_event* loop){
+	sd_event_loop(loop);
+	sd_event_unref(loop);
+}
+
+
 /**
  * constructor
  */
@@ -99,14 +106,14 @@ LibHomeScreen::LibHomeScreen()
  */
 LibHomeScreen::~LibHomeScreen()
 {
-	if(mploop)
-	{
-		sd_event_unref(mploop);
-	}
 	if(sp_websock != NULL)
 	{
 		afb_wsj1_unref(sp_websock);
 	}
+	if(mploop)
+	{
+		sd_event_exit(mploop, 0);
+	}
 }
 
 /**
@@ -177,13 +184,19 @@ int LibHomeScreen::initialize_websocket()
 	mploop = NULL;
 	onEvent = nullptr;
 	onReply = nullptr;
-	int ret = sd_event_default(&mploop);
+	int ret = sd_event_new(&mploop);
 	if(ret < 0)
 	{
 		HMI_ERROR("libhomescreen","Failed to create event loop");
 		goto END;
 	}
 
+	{
+		// enforce context to avoid initialization/goto error
+		std::thread th(event_loop_run, mploop);
+		th.detach();
+	}
+
 	/* Initialize interface from websocket */
 	minterface.on_hangup = _on_hangup_static;
 	minterface.on_call = _on_call_static;
@@ -201,10 +214,6 @@ int LibHomeScreen::initialize_websocket()
 
 	return 0;
 END:
-	if(mploop)
-	{
-		sd_event_unref(mploop);
-	}
 	return -1;
 }
 
-- 
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