usr/src/lib/libpc/UNPACK.c

/*-
 * Copyright (c) 1979 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that: (1) source distributions retain this entire copyright
 * notice and comment, and (2) distributions including binaries display
 * the following acknowledgement:  ``This product includes software
 * developed by the University of California, Berkeley and its contributors''
 * in the documentation or other materials provided with the distribution
 * and in all advertising materials mentioning features or use of this
 * software. Neither the name of the University nor the names of its
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)UNPACK.c    1.4 (Berkeley) 4/9/90";
#endif /* not lint */

/*
 * unpack(z,a,i)
 *
 * with:        z and a as in pack
 *
 * semantics:   for j := u to v do
 *                      a[j-u+i] := z[j]
 */

UNPACK(i, a, z, size_a, lb_a, ub_a, size_z)

        long    i;      /* subscript into a to begin packing */
        char    *a;     /* pointer to structure a */
        char    *z;     /* pointer to structure z */
        long    size_a; /* sizeof(a_type) */
        long    lb_a;   /* lower bound of structure a */
        long    ub_a;   /* (upper bound of a) - (lb_a + sizeof(z_type)) */
        long    size_z; /* sizeof(z_type) */
{
        int             subscr;
        register char   *cp;
        register char   *zp = z;
        register char   *limit;

        subscr = i - lb_a;
        if (subscr < 0 || subscr > ub_a) {
                ERROR("i = %D: Bad i to unpack(z,a,i)\n", i);
                return;
        }
        cp = &a[subscr * size_a];
        limit = cp + size_z;
        do      {
                *cp++ = *zp++;
        } while (cp < limit);
}