From 273743466fa39a14bf7abf73f30427406684f3d3 Mon Sep 17 00:00:00 2001
From: Sebastien Douheret <sebastien.douheret@iot.bzh>
Date: Tue, 12 Dec 2017 10:15:23 +0100
Subject: [PATCH] Fixed crash on xds-agent or server disconnection (IOT-108)

---
 gdb-xds.go | 24 ++++++++++++++++++++++++
 main.go    | 10 ++++++++--
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/gdb-xds.go b/gdb-xds.go
index 406e4c6..15f8b6d 100644
--- a/gdb-xds.go
+++ b/gdb-xds.go
@@ -255,6 +255,25 @@ func (g *GdbXds) Init() (int, error) {
 		}
 	})
 
+	// Monitor XDS server configuration changes (and specifically connected status)
+	iosk.On(xaapiv1.EVTServerConfig, func(ev xaapiv1.EventMsg) {
+		svrCfg, err := ev.DecodeServerCfg()
+		if err == nil && !svrCfg.Connected {
+			// TODO: should wait that server will be connected back
+			if g.cbOnExit != nil {
+				g.cbOnExit(-1, fmt.Errorf("XDS Server disconnected"))
+			} else {
+				fmt.Printf("XDS Server disconnected")
+				os.Exit(-1)
+			}
+		}
+	})
+
+	args := xaapiv1.EventRegisterArgs{Name: xaapiv1.EVTServerConfig}
+	if err := g.httpCli.Post("/events/register", args, nil); err != nil {
+		return 0, err
+	}
+
 	return 0, nil
 }
 
@@ -304,6 +323,11 @@ func (g *GdbXds) Start(inferiorTTY bool) (int, error) {
 	// except if XDS_GDBSERVER_OUTPUT_NOFIX is defined
 	_, gdbserverNoFix := os.LookupEnv("XDS_GDBSERVER_OUTPUT_NOFIX")
 
+	// SDK ID must be set else $GDB cannot be resolved
+	if g.sdkID == "" {
+		return int(syscall.EINVAL), fmt.Errorf("sdkid must be set")
+	}
+
 	args := xaapiv1.ExecArgs{
 		ID:              g.prjID,
 		SdkID:           g.sdkID,
diff --git a/main.go b/main.go
index 3df9e1a..f7db365 100644
--- a/main.go
+++ b/main.go
@@ -340,7 +340,13 @@ endloop:
 		})
 
 		gdb.OnDisconnect(func(err error) {
-			fmt.Println("Disconnection: ", err.Error())
+			errMsg := "\nXDS-Agent disconnected"
+			if err != nil {
+				fmt.Printf("%s: %v\n", errMsg, err.Error())
+			} else {
+				fmt.Println(errMsg)
+			}
+
 			exitChan <- exitResult{err, int(syscall.ESHUTDOWN)}
 		})
 
@@ -461,8 +467,8 @@ endloop:
 						time.Sleep(time.Millisecond * 200)
 					}
 
-					gdb.Write(command + "\n")
 					log.Debugf("Send: <%v>", command)
+					gdb.Write(command + "\n")
 				}
 				log.Infof("Stdin scanner exit, close stdin (err=%v)", sc.Err())
 
-- 
2.16.6