From 81cd40668305099d127655ab5086517f52243306 Mon Sep 17 00:00:00 2001
From: David Cermak <cermak@espressif.com>
Date: Wed, 12 Jun 2019 21:27:03 +0200
Subject: [PATCH] lwip: support mdns queries

---
 components/lwip/Kconfig                       | 8 ++++++++
 components/lwip/port/esp32/include/lwipopts.h | 6 ++++++
 2 files changed, 14 insertions(+)

diff --git a/components/lwip/Kconfig b/components/lwip/Kconfig
index ec6787b80..6a5c9dd27 100644
--- a/components/lwip/Kconfig
+++ b/components/lwip/Kconfig
@@ -6,6 +6,14 @@ menu "LWIP"
         help
             The name this device will report to other devices on the network
 
+    config LWIP_DNS_SUPPORT_MDNS_QUERIES
+        bool "Enable mDNS queries in resolving host name"
+        default y
+        help
+            If this feature is enabled, standard API such as gethostbyname
+            support .local addresses by sending one shot multicast mDNS
+            query
+
     config LWIP_L2_TO_L3_COPY
         bool "Enable copy between Layer2 and Layer3 packets"
         default n
diff --git a/components/lwip/port/esp32/include/lwipopts.h b/components/lwip/port/esp32/include/lwipopts.h
index 884ffb880..5ad6c9cc5 100644
--- a/components/lwip/port/esp32/include/lwipopts.h
+++ b/components/lwip/port/esp32/include/lwipopts.h
@@ -549,6 +549,12 @@
  */
 #define SO_REUSE                        CONFIG_LWIP_SO_REUSE
 
+
+/**
+ * LWIP_DNS_SUPPORT_MDNS_QUERIES==1: Enable mDNS queries in hostname resolution.
+ * This option is set via menuconfig.
+ */
+#define LWIP_DNS_SUPPORT_MDNS_QUERIES   CONFIG_LWIP_DNS_SUPPORT_MDNS_QUERIES
 /**
  * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
  * to all local matches if SO_REUSEADDR is turned on.