From a6b585cccfcc1608b21a76de064591dd7c8c5f71 Mon Sep 17 00:00:00 2001
From: Jakob Olsson <jakob.olsson@iopsys.eu>
Date: Wed, 18 May 2022 10:29:40 +0200
Subject: [PATCH] map-agent: multiap: lock operations on backhaul file

---
 map-agent/files/lib/wifi/multiap | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/map-agent/files/lib/wifi/multiap b/map-agent/files/lib/wifi/multiap
index b59320882..5aa632478 100755
--- a/map-agent/files/lib/wifi/multiap
+++ b/map-agent/files/lib/wifi/multiap
@@ -774,11 +774,14 @@ set_uplink_backhaul_info() {
 	local ul_1905id=$1
 	local ul_mac=$2
 
-	json_load "$(cat $MAPFILE)"
-	json_add_string "backhaul_device_id" "$ul_1905id"
-	json_add_string "backhaul_macddr" "$ul_mac"
-	json_dump > "$MAPFILE"
-	json_cleanup
+	(
+		flock -x 200
+		json_load "$(cat $MAPFILE)"
+		json_add_string "backhaul_device_id" "$ul_1905id"
+		json_add_string "backhaul_macddr" "$ul_mac"
+		json_dump > "$MAPFILE"
+		json_cleanup
+	) 200>/var/lock/map.backhaul.lock
 }
 
 set_uplink() {
@@ -792,7 +795,10 @@ set_uplink() {
 	json_add_string "type" "$type"
 	json_add_string "ifname" "$ifname"
 	json_add_string "macaddr" "$hwaddr"
-	json_dump > "$MAPFILE"
+	(
+		flock -x 200
+		json_dump > "$MAPFILE"
+	) 200>/var/lock/map.backhaul.lock
 	json_cleanup
 
 	config_load mapagent
@@ -816,7 +822,14 @@ unset_uplink() {
 		ubus call map.agent toggle_fh '{"enable":false, "prevent_island":true, "ifname":"all"}'
 	fi
 
-	rm -f "$MAPFILE" > /dev/null 2>&1
+	(
+		flock -x 200
+		json_load "$(cat $MAPFILE)"
+		json_get_var bk_type type
+		json_cleanup
+
+		[ "$type" = "$bk_type" ] && rm -f "$MAPFILE" > /dev/null 2>&1
+	) 200>/var/lock/map.backhaul.lock
 }
 
 func=$1