[TCPIP]
[reactos.git] / reactos / lib / drivers / lwip / src / include / lwip / def.h
1 /*
2 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without modification,
6 * are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
25 * OF SUCH DAMAGE.
26 *
27 * This file is part of the lwIP TCP/IP stack.
28 *
29 * Author: Adam Dunkels <adam@sics.se>
30 *
31 */
32 #ifndef __LWIP_DEF_H__
33 #define __LWIP_DEF_H__
34
35 /* arch.h might define NULL already */
36 #include "lwip/arch.h"
37 #include "lwip/opt.h"
38
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42
43 #define LWIP_MAX(x , y) (((x) > (y)) ? (x) : (y))
44 #define LWIP_MIN(x , y) (((x) < (y)) ? (x) : (y))
45
46 #ifndef NULL
47 #define NULL ((void *)0)
48 #endif
49
50 /** Get the absolute difference between 2 u32_t values (correcting overflows)
51 * 'a' is expected to be 'higher' (without overflow) than 'b'. */
52 #define LWIP_U32_DIFF(a, b) (((a) >= (b)) ? ((a) - (b)) : (((a) + ((b) ^ 0xFFFFFFFF) + 1)))
53
54 /* Endianess-optimized shifting of two u8_t to create one u16_t */
55 #if BYTE_ORDER == LITTLE_ENDIAN
56 #define LWIP_MAKE_U16(a, b) ((a << 8) | b)
57 #else
58 #define LWIP_MAKE_U16(a, b) ((b << 8) | a)
59 #endif
60
61 #ifndef LWIP_PLATFORM_BYTESWAP
62 #define LWIP_PLATFORM_BYTESWAP 0
63 #endif
64
65 #ifndef LWIP_PREFIX_BYTEORDER_FUNCS
66 /* workaround for naming collisions on some platforms */
67
68 #ifdef htons
69 #undef htons
70 #endif /* htons */
71 #ifdef htonl
72 #undef htonl
73 #endif /* htonl */
74 #ifdef ntohs
75 #undef ntohs
76 #endif /* ntohs */
77 #ifdef ntohl
78 #undef ntohl
79 #endif /* ntohl */
80
81 #define htons(x) lwip_htons(x)
82 #define ntohs(x) lwip_ntohs(x)
83 #define htonl(x) lwip_htonl(x)
84 #define ntohl(x) lwip_ntohl(x)
85 #endif /* LWIP_PREFIX_BYTEORDER_FUNCS */
86
87 #if BYTE_ORDER == BIG_ENDIAN
88 #define lwip_htons(x) (x)
89 #define lwip_ntohs(x) (x)
90 #define lwip_htonl(x) (x)
91 #define lwip_ntohl(x) (x)
92 #define PP_HTONS(x) (x)
93 #define PP_NTOHS(x) (x)
94 #define PP_HTONL(x) (x)
95 #define PP_NTOHL(x) (x)
96 #else /* BYTE_ORDER != BIG_ENDIAN */
97 #if LWIP_PLATFORM_BYTESWAP
98 #define lwip_htons(x) LWIP_PLATFORM_HTONS(x)
99 #define lwip_ntohs(x) LWIP_PLATFORM_HTONS(x)
100 #define lwip_htonl(x) LWIP_PLATFORM_HTONL(x)
101 #define lwip_ntohl(x) LWIP_PLATFORM_HTONL(x)
102 #else /* LWIP_PLATFORM_BYTESWAP */
103 u16_t lwip_htons(u16_t x);
104 u16_t lwip_ntohs(u16_t x);
105 u32_t lwip_htonl(u32_t x);
106 u32_t lwip_ntohl(u32_t x);
107 #endif /* LWIP_PLATFORM_BYTESWAP */
108
109 /* These macros should be calculated by the preprocessor and are used
110 with compile-time constants only (so that there is no little-endian
111 overhead at runtime). */
112 #define PP_HTONS(x) ((((x) & 0xff) << 8) | (((x) & 0xff00) >> 8))
113 #define PP_NTOHS(x) PP_HTONS(x)
114 #define PP_HTONL(x) ((((x) & 0xff) << 24) | \
115 (((x) & 0xff00) << 8) | \
116 (((x) & 0xff0000UL) >> 8) | \
117 (((x) & 0xff000000UL) >> 24))
118 #define PP_NTOHL(x) PP_HTONL(x)
119
120 #endif /* BYTE_ORDER == BIG_ENDIAN */
121
122 #ifdef __cplusplus
123 }
124 #endif
125
126 #endif /* __LWIP_DEF_H__ */
127