From ee2fe993dd86c53f22a03a76414d821588e9148f Mon Sep 17 00:00:00 2001
From: Scott Shawcroft <scott@tannewt.org>
Date: Thu, 12 Jan 2023 14:56:06 -0800
Subject: [PATCH] Fix repeated MDNS use on Pico W

---
 ports/raspberrypi/common-hal/mdns/Server.c | 19 +++++++++++++------
 shared-bindings/mdns/Server.c              |  3 ++-
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/ports/raspberrypi/common-hal/mdns/Server.c b/ports/raspberrypi/common-hal/mdns/Server.c
index e9b08efa33..38f3a70f76 100644
--- a/ports/raspberrypi/common-hal/mdns/Server.c
+++ b/ports/raspberrypi/common-hal/mdns/Server.c
@@ -36,21 +36,28 @@
 #include "lwip/apps/mdns.h"
 #include "lwip/prot/dns.h"
 
+// Track if we've inited the LWIP MDNS at all. It expects to only init once.
+// Subsequent times, we restart it.
+STATIC bool inited = false;
 // Track if we are globally inited. This essentially forces one inited MDNS
 // object at a time. (But ignores MDNS objects that are deinited.)
-STATIC bool inited = false;
+STATIC bool object_inited = false;
 
 #define NETIF_STA (&cyw43_state.netif[CYW43_ITF_STA])
 #define NETIF_AP (&cyw43_state.netif[CYW43_ITF_AP])
 
 void mdns_server_construct(mdns_server_obj_t *self, bool workflow) {
-    if (inited) {
+    if (object_inited) {
         self->inited = false;
         return;
     }
 
-    mdns_resp_init();
-    inited = true;
+    if (!inited) {
+        mdns_resp_init();
+        inited = true;
+    } else {
+        mdns_resp_restart(NETIF_STA);
+    }
     self->inited = true;
 
     uint8_t mac[6];
@@ -72,7 +79,7 @@ void common_hal_mdns_server_construct(mdns_server_obj_t *self, mp_obj_t network_
         mp_raise_ValueError(translate("mDNS only works with built-in WiFi"));
         return;
     }
-    if (inited) {
+    if (object_inited) {
         mp_raise_RuntimeError(translate("mDNS already initialized"));
     }
     mdns_server_construct(self, false);
@@ -83,7 +90,7 @@ void common_hal_mdns_server_deinit(mdns_server_obj_t *self) {
         return;
     }
     self->inited = false;
-    inited = false;
+    object_inited = false;
     mdns_resp_remove_netif(NETIF_STA);
 }
 
diff --git a/shared-bindings/mdns/Server.c b/shared-bindings/mdns/Server.c
index 2f3a0c7085..0d06d67f0d 100644
--- a/shared-bindings/mdns/Server.c
+++ b/shared-bindings/mdns/Server.c
@@ -64,7 +64,7 @@ STATIC mp_obj_t mdns_server_make_new(const mp_obj_type_t *type, size_t n_args, s
     }
     #endif
 
-    mdns_server_obj_t *self = m_new_obj(mdns_server_obj_t);
+    mdns_server_obj_t *self = m_new_obj_with_finaliser(mdns_server_obj_t);
     self->base.type = &mdns_server_type;
     common_hal_mdns_server_construct(self, args[ARG_network_interface].u_obj);
 
@@ -205,6 +205,7 @@ STATIC const mp_rom_map_elem_t mdns_server_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_find),              MP_ROM_PTR(&mdns_server_find_obj) },
     { MP_ROM_QSTR(MP_QSTR_advertise_service), MP_ROM_PTR(&mdns_server_advertise_service_obj) },
 
+    { MP_ROM_QSTR(MP_QSTR___del__),           MP_ROM_PTR(&mdns_server_deinit_obj) },
     { MP_ROM_QSTR(MP_QSTR_deinit),            MP_ROM_PTR(&mdns_server_deinit_obj) },
 };