Diff: LPC2368/lwip/include/lwip/def.h

Revision:

4:9cec8b1dcf09

Parent:

1:ba68cceb2917

Child:

5:bc7df6da7589

--- a/LPC2368/lwip/include/lwip/def.h	Fri Jun 18 10:28:59 2010 +0000
+++ b/LPC2368/lwip/include/lwip/def.h	Fri Jul 09 14:34:26 2010 +0000
@@ -39,7 +39,6 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
-
 #define LWIP_MAX(x , y)  (((x) > (y)) ? (x) : (y))
 #define LWIP_MIN(x , y)  (((x) < (y)) ? (x) : (y))
 
@@ -47,6 +46,24 @@
 #define NULL ((void *)0)
 #endif
 
+/** Get the absolute difference between 2 u32_t values (correcting overflows)
+ * 'a' is expected to be 'higher' (without overflow) than 'b'. */
+#define LWIP_U32_DIFF(a, b) (((a) >= (b)) ? ((a) - (b)) : (((a) + ((b) ^ 0xFFFFFFFF) + 1))) 
+
+/* Endianess-optimized shifting of two u8_t to create one u16_t */
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define LWIP_MAKE_U16(a, b) ((a << 8) | b)
+#else
+#define LWIP_MAKE_U16(a, b) ((b << 8) | a)
+#endif 
+
+#ifndef LWIP_PLATFORM_BYTESWAP
+#define LWIP_PLATFORM_BYTESWAP 0
+#endif
+
+#ifndef LWIP_PREFIX_BYTEORDER_FUNCS
+/* workaround for naming collisions on some platforms */
+
 #ifdef htons
 #undef htons
 #endif /* htons */
@@ -60,38 +77,46 @@
 #undef ntohl
 #endif /* ntohl */
 
-#ifndef LWIP_PLATFORM_BYTESWAP
-#define LWIP_PLATFORM_BYTESWAP 0
-#endif
+#define htons(x) lwip_htons(x)
+#define ntohs(x) lwip_ntohs(x)
+#define htonl(x) lwip_htonl(x)
+#define ntohl(x) lwip_ntohl(x)
+#endif /* LWIP_PREFIX_BYTEORDER_FUNCS */
 
 #if BYTE_ORDER == BIG_ENDIAN
-#define htons(x) (x)
-#define ntohs(x) (x)
-#define htonl(x) (x)
-#define ntohl(x) (x)
+#define lwip_htons(x) (x)
+#define lwip_ntohs(x) (x)
+#define lwip_htonl(x) (x)
+#define lwip_ntohl(x) (x)
+#define PP_HTONS(x) (x)
+#define PP_NTOHS(x) (x)
+#define PP_HTONL(x) (x)
+#define PP_NTOHL(x) (x)
 #else /* BYTE_ORDER != BIG_ENDIAN */
-#ifdef LWIP_PREFIX_BYTEORDER_FUNCS
-/* workaround for naming collisions on some platforms */
-#define htons lwip_htons
-#define ntohs lwip_ntohs
-#define htonl lwip_htonl
-#define ntohl lwip_ntohl
-#endif /* LWIP_PREFIX_BYTEORDER_FUNCS */
 #if LWIP_PLATFORM_BYTESWAP
-#define htons(x) LWIP_PLATFORM_HTONS(x)
-#define ntohs(x) LWIP_PLATFORM_HTONS(x)
-#define htonl(x) LWIP_PLATFORM_HTONL(x)
-#define ntohl(x) LWIP_PLATFORM_HTONL(x)
+#define lwip_htons(x) LWIP_PLATFORM_HTONS(x)
+#define lwip_ntohs(x) LWIP_PLATFORM_HTONS(x)
+#define lwip_htonl(x) LWIP_PLATFORM_HTONL(x)
+#define lwip_ntohl(x) LWIP_PLATFORM_HTONL(x)
 #else /* LWIP_PLATFORM_BYTESWAP */
-u16_t htons(u16_t x);
-u16_t ntohs(u16_t x);
-u32_t htonl(u32_t x);
-u32_t ntohl(u32_t x);
+u16_t lwip_htons(u16_t x);
+u16_t lwip_ntohs(u16_t x);
+u32_t lwip_htonl(u32_t x);
+u32_t lwip_ntohl(u32_t x);
 #endif /* LWIP_PLATFORM_BYTESWAP */
 
-#endif /* BYTE_ORDER == BIG_ENDIAN */
+/* These macros should be calculated by the preprocessor and are used
+   with compile-time constants only (so that there is no little-endian
+   overhead at runtime). */
+#define PP_HTONS(x) ((((x) & 0xff) << 8) | (((x) & 0xff00) >> 8))
+#define PP_NTOHS(x) PP_HTONS(x)
+#define PP_HTONL(x) ((((x) & 0xff) << 24) | \
+                     (((x) & 0xff00) << 8) | \
+                     (((x) & 0xff0000UL) >> 8) | \
+                     (((x) & 0xff000000UL) >> 24))
+#define PP_NTOHL(x) PP_HTONL(x)
 
-#define PP_HTONS htons
+#endif /* BYTE_ORDER == BIG_ENDIAN */
 
 #ifdef __cplusplus
 }