fix message traversal error

generate_offline.go

@@ -251,27 +251,15 @@ func PointInBox(ax float64, ay float64, bxMin float64, byMin float64, bxMax floa
 
 var AREAS = GenerateAreas()
 
-func FindWaysAroundLocation(lat float64, lon float64) (Offline, error) {
-	offline := Offline{}
+func FindWaysAroundLocation(lat float64, lon float64) ([]byte, error) {
 	for _, area := range AREAS {
 		inBox := PointInBox(lat, lon, area.MinLat, area.MinLon, area.MaxLat, area.MaxLon)
 		if inBox {
 			boundsName := GenerateBoundsFileName(area.MinLat, area.MinLon, area.MaxLat, area.MaxLon)
 			fmt.Println(boundsName)
 			data, err := os.ReadFile(boundsName)
-			if err != nil {
-				return offline, err
-			}
-			msg, err := capnp.UnmarshalPacked(data)
-			if err != nil {
-				return offline, err
-			}
-			offline, err := ReadRootOffline(msg)
-			if err != nil {
-				return offline, err
-			}
-			return offline, nil
+			return data, err
 		}
 	}
-	return offline, nil
+	return []uint8{}, nil
 }

mapd.go

@@ -1,13 +1,15 @@
 package main
 
 import (
+	"capnproto.org/go/capnp/v3"
 	"encoding/json"
 	"flag"
 	"fmt"
 	"time"
 )
 
 type State struct {
+	Data         []uint8
 	Result       Offline
 	Way          CurrentWay
 	NextWay      Way
@@ -64,11 +66,19 @@ func main() {
 	coordinates, _ := GetParam(LAST_GPS_POSITION_PERSIST)
 	err := json.Unmarshal(coordinates, &pos)
 	loge(err)
-	state.Result, err = FindWaysAroundLocation(pos.Latitude, pos.Longitude)
+	state.Data, err = FindWaysAroundLocation(pos.Latitude, pos.Longitude)
 	loge(err)
 
 	for {
 		DownloadIfTriggered()
+
+		msg, err := capnp.UnmarshalPacked(state.Data)
+		loge(err)
+		if err == nil {
+			offline, err := ReadRootOffline(msg)
+			loge(err)
+			state.Result = offline
+		}
 		coordinates, err := GetParam(LAST_GPS_POSITION)
 		if err != nil {
 			loge(err)
@@ -79,7 +89,6 @@ func main() {
 			loge(err)
 			continue
 		}
-
 		state.Position = pos
 
 		if !PointInBox(pos.Latitude, pos.Longitude, state.Result.MinLat(), state.Result.MinLon(), state.Result.MaxLat(), state.Result.MaxLon()) {
@@ -88,11 +97,8 @@ func main() {
 			state.Way = CurrentWay{}
 			state.Result = Offline{}
 			state.NextWay = Way{}
-			res, err := FindWaysAroundLocation(pos.Latitude, pos.Longitude)
+			state.Data, err = FindWaysAroundLocation(pos.Latitude, pos.Longitude)
 			loge(err)
-			if err == nil {
-				state.Result = res
-			}
 		}
 		way, err := GetCurrentWay(&state, pos.Latitude, pos.Longitude)
 		if err == nil {
@@ -121,6 +127,7 @@ func main() {
 						Longitude:  state.MatchNode.Longitude(),
 						Speedlimit: nextSpeedLimit,
 					})
+
 					loge(err)
 					if err == nil {
 						err := PutParam(NEXT_MAP_SPEED_LIMIT, data)