inet.h

//
// inet.h
//
// Functions common to all TCP/IP modules, such as the Internet checksum and the
// byte order functions.
//
// Copyright (C) 2002 Michael Ringgaard. All rights reserved.
// Portions Copyright (C) 2001, Swedish Institute of Computer Science.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 
// 1. Redistributions of source code must retain the above copyright 
//    notice, this list of conditions and the following disclaimer.  
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.  
// 3. Neither the name of the project nor the names of its contributors
//    may be used to endorse or promote products derived from this software
//    without specific prior written permission. 
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
// SUCH DAMAGE.
// 

#ifndef INET_H
#define INET_H

unsigned short inet_chksum(void *data, int len);
unsigned short inet_chksum_pbuf(struct pbuf *p);
unsigned short inet_chksum_pseudo(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, unsigned char proto, unsigned short proto_len);

#if BYTE_ORDER == BIG_ENDIAN

#define HTONS(n) (n)
#define NTOHS(n) (n)
#define HTONL(n) (n)
#define NTOHL(n) (n)

#else

#define HTONS(n) (((((unsigned short)(n) & 0xFF)) << 8) | (((unsigned short)(n) & 0xFF00) >> 8))
#define NTOHS(n) (((((unsigned short)(n) & 0xFF)) << 8) | (((unsigned short)(n) & 0xFF00) >> 8))

#define HTONL(n) (((((unsigned long)(n) & 0xFF)) << 24) | \
                  ((((unsigned long)(n) & 0xFF00)) << 8) | \
                  ((((unsigned long)(n) & 0xFF0000)) >> 8) | \
                  ((((unsigned long)(n) & 0xFF000000)) >> 24))

#define NTOHL(n) (((((unsigned long)(n) & 0xFF)) << 24) | \
                  ((((unsigned long)(n) & 0xFF00)) << 8) | \
                  ((((unsigned long)(n) & 0xFF0000)) >> 8) | \
                  ((((unsigned long)(n) & 0xFF000000)) >> 24))
#endif

unsigned short htons(unsigned short n);
unsigned short ntohs(unsigned short n);
unsigned long htonl(unsigned long n);
unsigned long ntohl(unsigned long n);

#define htons(n) HTONS(n)
#define ntohs(n) NTOHS(n)

#define htonl(n) HTONL(n)
#define ntohl(n) NTOHL(n)

#endif