xref: /titanic_50/usr/src/lib/libast/common/string/swapget.c (revision 3e14f97f673e8a630f076077de35afdd43dc1587)
1da2e3ebdSchin /***********************************************************************
2da2e3ebdSchin *                                                                      *
3da2e3ebdSchin *               This software is part of the ast package               *
4*3e14f97fSRoger A. Faulkner *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
5da2e3ebdSchin *                      and is licensed under the                       *
6da2e3ebdSchin *                  Common Public License, Version 1.0                  *
77c2fbfb3SApril Chin *                    by AT&T Intellectual Property                     *
8da2e3ebdSchin *                                                                      *
9da2e3ebdSchin *                A copy of the License is available at                 *
10da2e3ebdSchin *            http://www.opensource.org/licenses/cpl1.0.txt             *
11da2e3ebdSchin *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12da2e3ebdSchin *                                                                      *
13da2e3ebdSchin *              Information and Software Systems Research               *
14da2e3ebdSchin *                            AT&T Research                             *
15da2e3ebdSchin *                           Florham Park NJ                            *
16da2e3ebdSchin *                                                                      *
17da2e3ebdSchin *                 Glenn Fowler <gsf@research.att.com>                  *
18da2e3ebdSchin *                  David Korn <dgk@research.att.com>                   *
19da2e3ebdSchin *                   Phong Vo <kpv@research.att.com>                    *
20da2e3ebdSchin *                                                                      *
21da2e3ebdSchin ***********************************************************************/
22da2e3ebdSchin #pragma prototyped
23da2e3ebdSchin /*
24da2e3ebdSchin  * Glenn Fowler
25da2e3ebdSchin  * AT&T Research
26da2e3ebdSchin  *
27da2e3ebdSchin  * internal representation conversion support
28da2e3ebdSchin  */
29da2e3ebdSchin 
30da2e3ebdSchin #include <ast.h>
31da2e3ebdSchin #include <swap.h>
32da2e3ebdSchin 
33da2e3ebdSchin /*
34da2e3ebdSchin  * get int_n from b according to op
35da2e3ebdSchin  */
36da2e3ebdSchin 
37da2e3ebdSchin intmax_t
swapget(int op,const void * b,int n)38da2e3ebdSchin swapget(int op, const void* b, int n)
39da2e3ebdSchin {
40da2e3ebdSchin 	register unsigned char*	p;
41da2e3ebdSchin 	register unsigned char*	d;
42da2e3ebdSchin 	intmax_t		v;
43da2e3ebdSchin 	unsigned char		tmp[sizeof(intmax_t)];
44da2e3ebdSchin 
45da2e3ebdSchin 	if (n > sizeof(intmax_t))
46da2e3ebdSchin 		n = sizeof(intmax_t);
47da2e3ebdSchin 	if (op) swapmem(op, b, d = tmp, n);
48da2e3ebdSchin 	else d = (unsigned char*)b;
49da2e3ebdSchin 	p = d + n;
50da2e3ebdSchin 	v = 0;
51da2e3ebdSchin 	while (d < p)
52da2e3ebdSchin 	{
53da2e3ebdSchin 		v <<= CHAR_BIT;
54da2e3ebdSchin 		v |= *d++;
55da2e3ebdSchin 	}
56da2e3ebdSchin 	return v;
57da2e3ebdSchin }
58