e12cb143 |
1 | /* Toggle the 16 bit unsigned integer pointed by *p from little endian to |
2 | * big endian */ |
3 | void memrev16(void *p) { |
4 | unsigned char *x = p, t; |
5 | |
6 | t = x[0]; |
7 | x[0] = x[1]; |
8 | x[1] = t; |
9 | } |
10 | |
11 | /* Toggle the 32 bit unsigned integer pointed by *p from little endian to |
12 | * big endian */ |
13 | void memrev32(void *p) { |
14 | unsigned char *x = p, t; |
15 | |
16 | t = x[0]; |
17 | x[0] = x[3]; |
18 | x[3] = t; |
19 | t = x[1]; |
20 | x[1] = x[2]; |
21 | x[2] = t; |
22 | } |
23 | |
24 | /* Toggle the 64 bit unsigned integer pointed by *p from little endian to |
25 | * big endian */ |
26 | void memrev64(void *p) { |
27 | unsigned char *x = p, t; |
28 | |
29 | t = x[0]; |
30 | x[0] = x[7]; |
31 | x[7] = t; |
32 | t = x[1]; |
33 | x[1] = x[6]; |
34 | x[6] = t; |
35 | t = x[2]; |
36 | x[2] = x[5]; |
37 | x[5] = t; |
38 | t = x[3]; |
39 | x[3] = x[4]; |
40 | x[4] = t; |
41 | } |
42 | |
43 | #ifdef TESTMAIN |
44 | #include <stdio.h> |
45 | |
46 | int main(void) { |
47 | char buf[32]; |
48 | |
49 | sprintf(buf,"ciaoroma"); |
50 | memrev16(buf); |
51 | printf("%s\n", buf); |
52 | |
53 | sprintf(buf,"ciaoroma"); |
54 | memrev32(buf); |
55 | printf("%s\n", buf); |
56 | |
57 | sprintf(buf,"ciaoroma"); |
58 | memrev64(buf); |
59 | printf("%s\n", buf); |
60 | |
61 | return 0; |
62 | } |
63 | #endif |