| /** |
| * @file |
| * Common functions used throughout the stack. |
| * |
| */ |
| |
| /* |
| * Copyright (c) 2001-2004 Swedish Institute of Computer Science. |
| * All rights reserved. |
| * |
| * 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. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. |
| * |
| * This file is part of the lwIP TCP/IP stack. |
| * |
| * Author: Simon Goldschmidt |
| * |
| */ |
| |
| #include "lwip/opt.h" |
| #include "lwip/def.h" |
| |
| /** |
| * These are reference implementations of the byte swapping functions. |
| * Again with the aim of being simple, correct and fully portable. |
| * Byte swapping is the second thing you would want to optimize. You will |
| * need to port it to your architecture and in your cc.h: |
| * |
| * #define LWIP_PLATFORM_BYTESWAP 1 |
| * #define LWIP_PLATFORM_HTONS(x) <your_htons> |
| * #define LWIP_PLATFORM_HTONL(x) <your_htonl> |
| * |
| * Note ntohs() and ntohl() are merely references to the htonx counterparts. |
| */ |
| |
| #if (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) |
| |
| /** |
| * Convert an u16_t from host- to network byte order. |
| * |
| * @param n u16_t in host byte order |
| * @return n in network byte order |
| */ |
| u16_t |
| lwip_htons(u16_t n) |
| { |
| return ((n & 0xff) << 8) | ((n & 0xff00) >> 8); |
| } |
| |
| /** |
| * Convert an u16_t from network- to host byte order. |
| * |
| * @param n u16_t in network byte order |
| * @return n in host byte order |
| */ |
| u16_t |
| lwip_ntohs(u16_t n) |
| { |
| return lwip_htons(n); |
| } |
| |
| /** |
| * Convert an u32_t from host- to network byte order. |
| * |
| * @param n u32_t in host byte order |
| * @return n in network byte order |
| */ |
| u32_t |
| lwip_htonl(u32_t n) |
| { |
| return ((n & 0xff) << 24) | |
| ((n & 0xff00) << 8) | |
| ((n & 0xff0000UL) >> 8) | |
| ((n & 0xff000000UL) >> 24); |
| } |
| |
| /** |
| * Convert an u32_t from network- to host byte order. |
| * |
| * @param n u32_t in network byte order |
| * @return n in host byte order |
| */ |
| u32_t |
| lwip_ntohl(u32_t n) |
| { |
| return lwip_htonl(n); |
| } |
| |
| #endif /* (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) */ |