From c342880b6350e66ab099476a5cb19931af63dded Mon Sep 17 00:00:00 2001
From: andig <cpuidle@gmx.de>
Date: Sun, 6 Nov 2022 12:07:35 +0100
Subject: [PATCH] Fix a race condition when stopping the charging session

---
 core/loadpoint.go          | 16 ++++++++--------
 core/loadpoint_api.go      | 16 +++++++++++++++-
 core/loadpoint_database.go |  2 +-
 core/site.go               |  1 +
 4 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/core/loadpoint.go b/core/loadpoint.go
index f21647823..6c7892d52 100644
--- a/core/loadpoint.go
+++ b/core/loadpoint.go
@@ -412,8 +412,8 @@ func (lp *LoadPoint) evVehicleConnectHandler() {
 	lp.log.INFO.Printf("car connected")
 
 	// energy
-	lp.chargedEnergy = 0
-	lp.publish("chargedEnergy", lp.chargedEnergy)
+	lp.setChargedEnergy(0)
+	lp.publish("chargedEnergy", lp.getChargedEnergy())
 
 	// duration
 	lp.connectedTime = lp.clock.Now()
@@ -446,7 +446,7 @@ func (lp *LoadPoint) evVehicleDisconnectHandler() {
 	lp.resetMeasuredPhases()
 
 	// energy and duration
-	lp.publish("chargedEnergy", lp.chargedEnergy)
+	lp.publish("chargedEnergy", lp.getChargedEnergy())
 	lp.publish("connectedDuration", lp.clock.Since(lp.connectedTime))
 
 	// remove charger vehicle id and stop potential detection
@@ -698,7 +698,7 @@ func (lp *LoadPoint) setStatus(status api.ChargeStatus) {
 func (lp *LoadPoint) targetEnergyReached() bool {
 	return (lp.vehicle == nil || lp.vehicleHasFeature(api.Offline)) &&
 		lp.targetEnergy > 0 &&
-		lp.chargedEnergy/1e3 >= float64(lp.targetEnergy)
+		lp.getChargedEnergy()/1e3 >= float64(lp.targetEnergy)
 }
 
 // targetSocReached checks if target is configured and reached.
@@ -1510,7 +1510,7 @@ func (lp *LoadPoint) updateChargeCurrents() {
 // publish charged energy and duration
 func (lp *LoadPoint) publishChargeProgress() {
 	if f, err := lp.chargeRater.ChargedEnergy(); err == nil {
-		lp.chargedEnergy = 1e3 * f // convert to Wh
+		lp.setChargedEnergy(1e3 * f) // convert to Wh
 	} else {
 		lp.log.ERROR.Printf("charge rater: %v", err)
 	}
@@ -1521,7 +1521,7 @@ func (lp *LoadPoint) publishChargeProgress() {
 		lp.log.ERROR.Printf("charge timer: %v", err)
 	}
 
-	lp.publish("chargedEnergy", lp.chargedEnergy)
+	lp.publish("chargedEnergy", lp.getChargedEnergy())
 	lp.publish("chargeDuration", lp.chargeDuration)
 	if _, ok := lp.chargeMeter.(api.MeterEnergy); ok {
 		lp.publish("chargeTotalImport", lp.chargeMeterTotal())
@@ -1566,7 +1566,7 @@ func (lp *LoadPoint) publishSoCAndRange() {
 		// guard for socEstimator removed by api
 		if se := lp.socEstimator; se != nil {
 			lp.socUpdated = lp.clock.Now()
-			f, err = se.SoC(lp.chargedEnergy)
+			f, err = se.SoC(lp.getChargedEnergy())
 		} else {
 			return
 		}
@@ -1708,7 +1708,7 @@ func (lp *LoadPoint) Update(sitePower float64, cheap, batteryBuffered bool) {
 		}
 
 	case lp.targetEnergyReached():
-		lp.log.DEBUG.Printf("targetEnergy reached: %.0fkWh > %dkWh", lp.chargedEnergy/1e3, lp.targetEnergy)
+		lp.log.DEBUG.Printf("targetEnergy reached: %.0fkWh > %dkWh", lp.getChargedEnergy()/1e3, lp.targetEnergy)
 		err = lp.disableUnlessClimater()
 
 	case lp.targetSocReached():
diff --git a/core/loadpoint_api.go b/core/loadpoint_api.go
index 766992569..a7f41380c 100644
--- a/core/loadpoint_api.go
+++ b/core/loadpoint_api.go
@@ -49,7 +49,21 @@ func (lp *LoadPoint) SetMode(mode api.ChargeMode) {
 	}
 }
 
-// GetTargetSoC returns loadpoint charge target energy
+// getChargedEnergy returns loadpoint charge target energy
+func (lp *LoadPoint) getChargedEnergy() float64 {
+	lp.Lock()
+	defer lp.Unlock()
+	return lp.chargedEnergy
+}
+
+// setChargedEnergy returns loadpoint charge target energy
+func (lp *LoadPoint) setChargedEnergy(energy float64) {
+	lp.Lock()
+	defer lp.Unlock()
+	lp.chargedEnergy = energy
+}
+
+// GetTargetEnergy returns loadpoint charge target energy
 func (lp *LoadPoint) GetTargetEnergy() int {
 	lp.Lock()
 	defer lp.Unlock()
diff --git a/core/loadpoint_database.go b/core/loadpoint_database.go
index 8d09a5974..0553a1df8 100644
--- a/core/loadpoint_database.go
+++ b/core/loadpoint_database.go
@@ -48,7 +48,7 @@ func (lp *LoadPoint) stopSession() {
 		return
 	}
 
-	lp.session.Stop(lp.chargedEnergy, lp.chargeMeterTotal())
+	lp.session.Stop(lp.getChargedEnergy(), lp.chargeMeterTotal())
 
 	lp.db.Persist(lp.session)
 }
diff --git a/core/site.go b/core/site.go
index 59613e659..48cb66081 100644
--- a/core/site.go
+++ b/core/site.go
@@ -117,6 +117,7 @@ func NewSiteFromConfig(
 				return nil, err
 			}
 
+			// NOTE: this requires stopSession to respect async access
 			shutdown.Register(lp.stopSession)
 		}
 	}