Fixed bug #29148 (Incorrect PBUF_POOL_BUFSIZE for ports where ETH_PAD_SIZE > 0) by moving definition of ETH_PAD_SIZE to opt.h and basing PBUF_LINK_HLEN on it.

CHANGELOG

@@ -158,6 +158,11 @@ HISTORY
 
   ++ Bugfixes:
 
+  2010-03-14: Simon Goldschmidt
+  * opt.h, etharp.h: Fixed bug #29148 (Incorrect PBUF_POOL_BUFSIZE for ports
+    where ETH_PAD_SIZE > 0) by moving definition of ETH_PAD_SIZE to opt.h
+    and basing PBUF_LINK_HLEN on it.
+
   2010-03-08: Simon Goldschmidt
   * netif.c, ipv4/ip.c: task #10241 (AutoIP: don't break existing connections
     when assiging routable address): when checking incoming packets and

src/include/lwip/opt.h

@@ -435,6 +435,16 @@
 #define LWIP_ETHERNET                   (LWIP_ARP || PPPOE_SUPPORT)
 #endif
 
+/** ETH_PAD_SIZE: number of bytes added before the ethernet header to ensure
+ * alignment of payload after that header. Since the header is 14 bytes long,
+ * without this padding e.g. addresses in the IP header will not be aligned
+ * on a 32-bit boundary, so setting this to 2 can speed up 32-bit-platforms.
+ */
+#ifndef ETH_PAD_SIZE
+#define ETH_PAD_SIZE                    0
+#endif
+
+
 /*
    --------------------------------
    ---------- IP options ----------
@@ -997,7 +1007,7 @@
  * Ethernet.
  */
 #ifndef PBUF_LINK_HLEN
-#define PBUF_LINK_HLEN                  14
+#define PBUF_LINK_HLEN                  (14 + ETH_PAD_SIZE)
 #endif
 
 /**

src/include/netif/etharp.h

@@ -48,10 +48,6 @@
 extern "C" {
 #endif
 
-#ifndef ETH_PAD_SIZE
-#define ETH_PAD_SIZE          0
-#endif
-
 #ifndef ETHARP_HWADDR_LEN
 #define ETHARP_HWADDR_LEN     6
 #endif