Implement task #14367: Hooks need a better place to be defined

We now have a #define for a header file name that is #included in every .c file that provides hooks.

src/core/ipv4/etharp.c

@@ -56,6 +56,10 @@
 
 #include <string.h>
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 #if LWIP_IPV4 && LWIP_ARP /* don't build if not configured for use in lwipopts.h */
 
 /** Re-request a used ARP entry 1 minute before it would expire to prevent

src/core/ipv4/icmp.c

@@ -51,6 +51,10 @@
 
 #include <string.h>
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 /** Small optimization: set to 0 if incoming PBUF_POOL pbuf always can be
  * used to modify and send a response packet (and to 1 if this is not the case,
  * e.g. when link header is stripped of when receiving) */

src/core/ipv4/ip4.c

@@ -59,6 +59,10 @@
 
 #include <string.h>
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 /** Set this to 0 in the rare case of wanting to call an extra function to
  * generate the IP checksum (in contrast to calculating it on-the-fly). */
 #ifndef LWIP_INLINE_IP_CHKSUM

src/core/ipv6/ip6.c

@@ -60,6 +60,10 @@
 #include "lwip/debug.h"
 #include "lwip/stats.h"
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 /**
  * Finds the appropriate network interface for a given IPv6 address. It tries to select
  * a netif following a sequence of heuristics:

src/core/ipv6/nd6.c

@@ -64,6 +64,10 @@
 
 #include <string.h>
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 #if LWIP_IPV6_DUP_DETECT_ATTEMPTS > IP6_ADDR_TENTATIVE_COUNT_MASK
 #error LWIP_IPV6_DUP_DETECT_ATTEMPTS > IP6_ADDR_TENTATIVE_COUNT_MASK
 #endif

src/core/memp.c

@@ -75,7 +75,6 @@
 #include "lwip/ip6_frag.h"
 #include "lwip/mld6.h"
 
-
 #define LWIP_MEMPOOL(name,num,size,desc) LWIP_MEMPOOL_DECLARE(name,num,size,desc)
 #include "lwip/priv/memp_std.h"
 
@@ -84,6 +83,10 @@ const struct memp_desc* const memp_pools[MEMP_MAX] = {
 #include "lwip/priv/memp_std.h"
 };
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 #if MEMP_MEM_MALLOC && MEMP_OVERFLOW_CHECK >= 2
 #undef MEMP_OVERFLOW_CHECK
 /* MEMP_OVERFLOW_CHECK >= 2 does not work with MEMP_MEM_MALLOC, use 1 instead */

src/core/tcp.c

@@ -62,6 +62,10 @@
 
 #include <string.h>
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 #ifndef TCP_LOCAL_PORT_RANGE_START
 /* From http://www.iana.org/assignments/port-numbers:
    "The Dynamic and/or Private Ports are those from 49152 through 65535" */

src/include/lwip/opt.h

@@ -2415,6 +2415,15 @@
  * @{
  */
 
+/**
+ * LWIP_HOOK_FILENAME: Custom filename to #include in files that provide hooks.
+ * Declare your hook function prototypes in there, you may also #include all headers
+ * providing data types that are need in this file.
+ */
+#ifdef __DOXYGEN__
+#define LWIP_HOOK_FILENAME "path/to/my/lwip_hooks.h"
+#endif
+
 /**
  * LWIP_HOOK_TCP_ISN:
  * Hook for generation of the Initial Sequence Number (ISN) for a new TCP

src/netif/ethernet.c

@@ -56,6 +56,10 @@
 #include "netif/ppp/pppoe.h"
 #endif /* PPPOE_SUPPORT */
 
+#ifdef LWIP_HOOK_FILENAME
+#include LWIP_HOOK_FILENAME
+#endif
+
 const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
 const struct eth_addr ethzero = {{0,0,0,0,0,0}};