From d785561eaee30916891690067a59f40acfeec3eb Mon Sep 17 00:00:00 2001
From: Joel Cunningham <joel.cunningham@me.com>
Date: Mon, 5 Feb 2018 17:30:00 -0600
Subject: [PATCH] tcpip: guard tcpip_msg enum/struct member with !CORE_LOCKING

enum tcpip_msg_type and struct tcpip_msg have members which are only
used when core locking and/or core locking input are disabled. Remove
these from the union to reduce the size. Remove from enum to prevent
usage when these are options are disabled

A quick sizeof test with MSVC 2013 showed a 4 byte size reduction for
struct tcpip_msg (16 bytes -> 12bytes) for the following configuration:
  LWIP_TCPIP_CORE_LOCKING        1
  LWIP_TCPIP_CORE_LOCKING_INPUT  1
  LWIP_TCPIP_TIMEOUT             0
---
 src/include/lwip/priv/tcpip_priv.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/include/lwip/priv/tcpip_priv.h b/src/include/lwip/priv/tcpip_priv.h
index 21643687..74be634b 100644
--- a/src/include/lwip/priv/tcpip_priv.h
+++ b/src/include/lwip/priv/tcpip_priv.h
@@ -111,9 +111,13 @@ typedef err_t (*tcpip_api_call_fn)(struct tcpip_api_call_data* call);
 err_t tcpip_api_call(tcpip_api_call_fn fn, struct tcpip_api_call_data *call);
 
 enum tcpip_msg_type {
+#if !LWIP_TCPIP_CORE_LOCKING
   TCPIP_MSG_API,
   TCPIP_MSG_API_CALL,
+#endif /* !LWIP_TCPIP_CORE_LOCKING */
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
   TCPIP_MSG_INPKT,
+#endif /* !LWIP_TCPIP_CORE_LOCKING_INPUT */
 #if LWIP_TCPIP_TIMEOUT && LWIP_TIMERS
   TCPIP_MSG_TIMEOUT,
   TCPIP_MSG_UNTIMEOUT,
@@ -125,6 +129,7 @@ enum tcpip_msg_type {
 struct tcpip_msg {
   enum tcpip_msg_type type;
   union {
+#if !LWIP_TCPIP_CORE_LOCKING
     struct {
       tcpip_callback_fn function;
       void* msg;
@@ -134,11 +139,14 @@ struct tcpip_msg {
       struct tcpip_api_call_data *arg;
       sys_sem_t *sem;
     } api_call;
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
     struct {
       struct pbuf *p;
       struct netif *netif;
       netif_input_fn input_fn;
     } inp;
+#endif /* !LWIP_TCPIP_CORE_LOCKING_INPUT */
     struct {
       tcpip_callback_fn function;
       void *ctx;