https-dns-proxy: ignore disabled dnsmasq DNS port

Author: dhrm1k

files/etc/init.d/https-dns-proxy

@@ -461,7 +461,8 @@ dnsmasq_instance_append_force_dns_port() {
 	local cfg="$1" instance_port
 	[ "$(uci_get 'dhcp' "$cfg")" = "dnsmasq" ] || return 1
 	config_get instance_port "$cfg" 'port' '53'
-		str_contains_word "$force_dns_port" "$instance_port" || force_dns_port="${force_dns_port:+${force_dns_port} }${instance_port}"
+	[ "$instance_port" = "0" ] && return 0
+	str_contains_word "$force_dns_port" "$instance_port" || force_dns_port="${force_dns_port:+${force_dns_port} }${instance_port}"
 }
 
 dnsmasq_doh_server() {

tests/run_tests.sh

@@ -505,6 +505,11 @@ force_dns_port="53 853"
 dnsmasq_instance_append_force_dns_port "cfg01"
 assert_eq "append_force_dns_port: already present port 53 not duplicated" "53 853" "$force_dns_port"
 
+uci_set "dhcp" "cfg03" ".type" "dnsmasq"
+uci_set "dhcp" "cfg03" "port" "0"
+dnsmasq_instance_append_force_dns_port "cfg03"
+assert_eq "append_force_dns_port: disabled dnsmasq port 0 ignored" "53 853" "$force_dns_port"
+
 uci_set "dhcp" "cfg02" ".type" "dnsmasq"
 uci_set "dhcp" "cfg02" "port" "5353"
 dnsmasq_instance_append_force_dns_port "cfg02"