1 /*
2 * Copyright 2006 Serge van den Boom <svdb@stack.nl>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18
19 // Routines for changing the endianness of values.
20 // I'm not using ntohs() etc. as those would require include files that may
21 // have conflicting definitions. This is a problem on Windows, where these
22 // functions are in winsock2.h, which includes windows.h, which includes
23 // pretty much Microsoft's complete collection of .h files.
24
25 #ifndef LIBS_NETWORK_BYTESEX_H_
26 #define LIBS_NETWORK_BYTESEX_H_
27
28 #include "port.h"
29 // for inline
30 #include "endian_uqm.h"
31 // for WORDS_BIGENDIAN
32 #include "types.h"
33
34 static inline uint16
swapBytes16(uint16 x)35 swapBytes16(uint16 x) {
36 return (x << 8) | (x >> 8);
37 }
38
39 static inline uint32
swapBytes32(uint32 x)40 swapBytes32(uint32 x) {
41 return (x << 24)
42 | ((x & 0x0000ff00) << 8)
43 | ((x & 0x00ff0000) >> 8)
44 | (x >> 24);
45 }
46
47 #ifdef WORDS_BIGENDIAN
48 // Already in network order.
49
50 static inline uint16
hton16(uint16 x)51 hton16(uint16 x) {
52 return x;
53 }
54
55 static inline uint32
hton32(uint32 x)56 hton32(uint32 x) {
57 return x;
58 }
59
60 static inline uint16
ntoh16(uint16 x)61 ntoh16(uint16 x) {
62 return x;
63 }
64
65 static inline uint32
ntoh32(uint32 x)66 ntoh32(uint32 x) {
67 return x;
68 }
69
70 #else /* !defined(WORDS_BIGENDIAN) */
71 // Need to swap bytes
72
73 static inline uint16
hton16(uint16 x)74 hton16(uint16 x) {
75 return swapBytes16(x);
76 }
77
78 static inline uint32
hton32(uint32 x)79 hton32(uint32 x) {
80 return swapBytes32(x);
81 }
82
83 static inline uint16
ntoh16(uint16 x)84 ntoh16(uint16 x) {
85 return swapBytes16(x);
86 }
87
88 static inline uint32
ntoh32(uint32 x)89 ntoh32(uint32 x) {
90 return swapBytes32(x);
91 }
92
93 #endif /* defined(WORDS_BIGENDIAN) */
94
95 #endif /* LIBS_NETWORK_BYTESEX_H_ */
96
97