def.h

00001 /*
00002  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00003  * All rights reserved. 
00004  * 
00005  * Redistribution and use in source and binary forms, with or without modification, 
00006  * are permitted provided that the following conditions are met:
00007  *
00008  * 1. Redistributions of source code must retain the above copyright notice,
00009  *    this list of conditions and the following disclaimer.
00010  * 2. Redistributions in binary form must reproduce the above copyright notice,
00011  *    this list of conditions and the following disclaimer in the documentation
00012  *    and/or other materials provided with the distribution.
00013  * 3. The name of the author may not be used to endorse or promote products
00014  *    derived from this software without specific prior written permission. 
00015  *
00016  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
00017  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
00018  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
00019  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
00020  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
00021  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
00022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
00023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
00024  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
00025  * OF SUCH DAMAGE.
00026  *
00027  * This file is part of the lwIP TCP/IP stack.
00028  * 
00029  * Author: Adam Dunkels <adam@sics.se>
00030  *
00031  */
00032 #ifndef __LWIP_DEF_H__
00033 #define __LWIP_DEF_H__
00034 
00035 /* arch.h might define NULL already */
00036 #include "lwip/arch.h"
00037 #include "lwip/opt.h"
00038 
00039 #ifdef __cplusplus
00040 extern "C" {
00041 #endif
00042 
00043 #define LWIP_MAX(x , y)  (((x) > (y)) ? (x) : (y))
00044 #define LWIP_MIN(x , y)  (((x) < (y)) ? (x) : (y))
00045 
00046 #ifndef NULL
00047 #define NULL ((void *)0)
00048 #endif
00049 
00050 /* Endianess-optimized shifting of two u8_t to create one u16_t */
00051 #if BYTE_ORDER == LITTLE_ENDIAN
00052 #define LWIP_MAKE_U16(a, b) ((a << 8) | b)
00053 #else
00054 #define LWIP_MAKE_U16(a, b) ((b << 8) | a)
00055 #endif 
00056 
00057 #ifndef LWIP_PLATFORM_BYTESWAP
00058 #define LWIP_PLATFORM_BYTESWAP 0
00059 #endif
00060 
00061 #ifndef LWIP_PREFIX_BYTEORDER_FUNCS
00062 /* workaround for naming collisions on some platforms */
00063 
00064 #ifdef htons
00065 #undef htons
00066 #endif /* htons */
00067 #ifdef htonl
00068 #undef htonl
00069 #endif /* htonl */
00070 #ifdef ntohs
00071 #undef ntohs
00072 #endif /* ntohs */
00073 #ifdef ntohl
00074 #undef ntohl
00075 #endif /* ntohl */
00076 
00077 #define htons(x) lwip_htons(x)
00078 #define ntohs(x) lwip_ntohs(x)
00079 #define htonl(x) lwip_htonl(x)
00080 #define ntohl(x) lwip_ntohl(x)
00081 #endif /* LWIP_PREFIX_BYTEORDER_FUNCS */
00082 
00083 #if BYTE_ORDER == BIG_ENDIAN
00084 #define lwip_htons(x) (x)
00085 #define lwip_ntohs(x) (x)
00086 #define lwip_htonl(x) (x)
00087 #define lwip_ntohl(x) (x)
00088 #define PP_HTONS(x) (x)
00089 #define PP_NTOHS(x) (x)
00090 #define PP_HTONL(x) (x)
00091 #define PP_NTOHL(x) (x)
00092 #else /* BYTE_ORDER != BIG_ENDIAN */
00093 #if LWIP_PLATFORM_BYTESWAP
00094 #define lwip_htons(x) LWIP_PLATFORM_HTONS(x)
00095 #define lwip_ntohs(x) LWIP_PLATFORM_HTONS(x)
00096 #define lwip_htonl(x) LWIP_PLATFORM_HTONL(x)
00097 #define lwip_ntohl(x) LWIP_PLATFORM_HTONL(x)
00098 #else /* LWIP_PLATFORM_BYTESWAP */
00099 u16_t lwip_htons(u16_t x);
00100 u16_t lwip_ntohs(u16_t x);
00101 u32_t lwip_htonl(u32_t x);
00102 u32_t lwip_ntohl(u32_t x);
00103 #endif /* LWIP_PLATFORM_BYTESWAP */
00104 
00105 /* These macros should be calculated by the preprocessor and are used
00106    with compile-time constants only (so that there is no little-endian
00107    overhead at runtime). */
00108 #define PP_HTONS(x) ((((x) & 0xff) << 8) | (((x) & 0xff00) >> 8))
00109 #define PP_NTOHS(x) PP_HTONS(x)
00110 #define PP_HTONL(x) ((((x) & 0xff) << 24) | \
00111                      (((x) & 0xff00) << 8) | \
00112                      (((x) & 0xff0000UL) >> 8) | \
00113                      (((x) & 0xff000000UL) >> 24))
00114 #define PP_NTOHL(x) PP_HTONL(x)
00115 
00116 #endif /* BYTE_ORDER == BIG_ENDIAN */
00117 
00118 #ifdef __cplusplus
00119 }
00120 #endif
00121 
00122 #endif /* __LWIP_DEF_H__ */
00123