swapget.c revision 3e14f97f673e8a630f076077de35afdd43dc1587
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2010 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Phong Vo <kpv@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* Glenn Fowler
* AT&T Research
*
* internal representation conversion support
*/
#include <ast.h>
#include <swap.h>
/*
* get int_n from b according to op
*/
intmax_t
swapget(int op, const void* b, int n)
{
register unsigned char* p;
register unsigned char* d;
intmax_t v;
unsigned char tmp[sizeof(intmax_t)];
if (n > sizeof(intmax_t))
n = sizeof(intmax_t);
if (op) swapmem(op, b, d = tmp, n);
else d = (unsigned char*)b;
p = d + n;
v = 0;
while (d < p)
{
v <<= CHAR_BIT;
v |= *d++;
}
return v;
}