src/common/byteswap.c

#ifndef lint
static const char RCSid[] = "$Id: byteswap.c,v 3.1 2006/12/23 17:27:45 greg Exp $";
#endif
/*
 * Byte swapping routines
 *
 * External symbols declared in rtio.h
 */

#include "copyright.h"
#include "rtio.h"

void
swap16(         /* swap n 16-bit words */
        char  *wp,
        size_t  n
)
{
        int     t;

        while (n-- > 0) {
                t = wp[0]; wp[0] = wp[1]; wp[1] = t;
                wp += 2;
        }
}


void
swap32(         /* swap n 32-bit words */
        char  *wp,
        size_t  n
)
{
        int     t;

        while (n-- > 0) {
                t = wp[0]; wp[0] = wp[3]; wp[3] = t;
                t = wp[1]; wp[1] = wp[2]; wp[2] = t;
                wp += 4;
        }
}


void
swap64(         /* swap n 64-bit words */
        char  *wp,
        size_t  n
)
{
        int     t;

        while (n-- > 0) {
                t = wp[0]; wp[0] = wp[7]; wp[7] = t;
                t = wp[1]; wp[1] = wp[6]; wp[6] = t;
                t = wp[2]; wp[2] = wp[5]; wp[5] = t;
                t = wp[3]; wp[3] = wp[4]; wp[4] = t;
                wp += 8;
        }
}

Revision:	3.2
Committed:	Fri Jan 15 18:31:38 2021 UTC (3 years, 4 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad5R4, HEAD
Changes since 3.1:	+10 -10 lines
Log Message:	More 64-bit addressing fixes
#	User	Rev	Content
1	greg	3.1	#ifndef lint
2	greg	3.2	static const char RCSid[] = "$Id: byteswap.c,v 3.1 2006/12/23 17:27:45 greg Exp $";
3	greg	3.1	#endif
4			/*
5			* Byte swapping routines
6			*
7			* External symbols declared in rtio.h
8			*/
9
10			#include "copyright.h"
11			#include "rtio.h"
12
13			void
14			swap16( /* swap n 16-bit words */
15	greg	3.2	char *wp,
16			size_t n
17	greg	3.1	)
18			{
19	greg	3.2	int t;
20	greg	3.1
21			while (n-- > 0) {
22			t = wp[0]; wp[0] = wp[1]; wp[1] = t;
23			wp += 2;
24			}
25			}
26
27
28			void
29			swap32( /* swap n 32-bit words */
30	greg	3.2	char *wp,
31			size_t n
32	greg	3.1	)
33			{
34	greg	3.2	int t;
35	greg	3.1
36			while (n-- > 0) {
37			t = wp[0]; wp[0] = wp[3]; wp[3] = t;
38			t = wp[1]; wp[1] = wp[2]; wp[2] = t;
39			wp += 4;
40			}
41			}
42
43
44			void
45			swap64( /* swap n 64-bit words */
46	greg	3.2	char *wp,
47			size_t n
48	greg	3.1	)
49			{
50	greg	3.2	int t;
51	greg	3.1
52			while (n-- > 0) {
53			t = wp[0]; wp[0] = wp[7]; wp[7] = t;
54			t = wp[1]; wp[1] = wp[6]; wp[6] = t;
55			t = wp[2]; wp[2] = wp[5]; wp[5] = t;
56			t = wp[3]; wp[3] = wp[4]; wp[4] = t;
57			wp += 8;
58			}
59			}
60