From 83286c3e784df2639b5e388b0d4d2b993742c29c Mon Sep 17 00:00:00 2001
From: Christopher Haster <chaster@utexas.edu>
Date: Thu, 18 Aug 2016 18:26:37 -0500
Subject: [PATCH] Adopted netconn_gethostbyname in the lwip interface

Provides proper integration with DHCP through lwip
---
 .../net/FEATURE_IPV4/lwip-interface/lwip_stack.c | 16 ++++++++++++++--
 .../net/FEATURE_IPV4/lwip-interface/lwipopts.h   |  1 +
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/features/net/FEATURE_IPV4/lwip-interface/lwip_stack.c b/features/net/FEATURE_IPV4/lwip-interface/lwip_stack.c
index 6aaee583da..cb67d70096 100644
--- a/features/net/FEATURE_IPV4/lwip-interface/lwip_stack.c
+++ b/features/net/FEATURE_IPV4/lwip-interface/lwip_stack.c
@@ -217,7 +217,7 @@ static int lwip_err_remap(err_t err) {
 
 
 /* LWIP network stack implementation */
-static nsapi_addr_t lwip_get_addr(nsapi_stack_t *stack)
+static nsapi_addr_t lwip_getaddr(nsapi_stack_t *stack)
 {
     if (!lwip_get_ip_address()) {
         return (nsapi_addr_t){0};
@@ -229,6 +229,17 @@ static nsapi_addr_t lwip_get_addr(nsapi_stack_t *stack)
     return addr;
 }
 
+static int lwip_gethostbyname(nsapi_stack_t *stack, nsapi_addr_t *addr, const char *host)
+{
+    err_t err = netconn_gethostbyname(host, (ip_addr_t *)addr->bytes);
+    if (err != ERR_OK) {
+        return NSAPI_ERROR_DNS_FAILURE;
+    }
+
+    addr->version = NSAPI_IPv4;
+    return 0;
+}
+
 static int lwip_socket_open(nsapi_stack_t *stack, nsapi_socket_t *handle, nsapi_protocol_t proto)
 {
     struct lwip_socket *s = lwip_arena_alloc();
@@ -445,7 +456,8 @@ static void lwip_socket_attach(nsapi_stack_t *stack, nsapi_socket_t handle, void
 
 /* LWIP network stack */
 const nsapi_stack_api_t lwip_stack_api = {
-    .get_ip_address     = lwip_get_addr,
+    .get_ip_address     = lwip_getaddr,
+    .gethostbyname      = lwip_gethostbyname,
     .socket_open        = lwip_socket_open,
     .socket_close       = lwip_socket_close,
     .socket_bind        = lwip_socket_bind,
diff --git a/features/net/FEATURE_IPV4/lwip-interface/lwipopts.h b/features/net/FEATURE_IPV4/lwip-interface/lwipopts.h
index 5e16535ba2..f557e353cb 100644
--- a/features/net/FEATURE_IPV4/lwip-interface/lwipopts.h
+++ b/features/net/FEATURE_IPV4/lwip-interface/lwipopts.h
@@ -66,6 +66,7 @@
 
 #define LWIP_DHCP                   1
 #define LWIP_DNS                    1
+#define LWIP_SOCKET                 0
 
 #define SO_REUSE                    1