1 /*-
2 * Copyright (c) 1979, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 */
7
8 #ifndef lint
9 static char sccsid[] = "@(#)PACK.c 8.1 (Berkeley) 06/06/93";
10 #endif /* not lint */
11
12 /*
13 * pack(a,i,z)
14 *
15 * with: a: array[m..n] of t
16 * z: packed array[u..v] of t
17 *
18 * semantics: for j := u to v do
19 * z[j] := a[j-u+i];
20 *
21 * need to check:
22 * 1. i >= m
23 * 2. i+(v-u) <= n (i.e. i-m <= (n-m)-(v-u))
24 *
25 * on stack: lv(z), lv(a), rv(i) (len 4)
26 *
27 * move w(t)*(v-u+1) bytes from lv(a)+w(t)*(i-m) to lv(z)
28 */
29
PACK(i,a,z,size_a,lb_a,ub_a,size_z)30 PACK(i, a, z, size_a, lb_a, ub_a, size_z)
31
32 long i; /* subscript into a to begin packing */
33 char *a; /* pointer to structure a */
34 char *z; /* pointer to structure z */
35 long size_a; /* sizeof(a_type) */
36 long lb_a; /* lower bound of structure a */
37 long ub_a; /* (upper bound of a) - (lb_a + sizeof(z_type)) */
38 long size_z; /* sizeof(z_type) */
39 {
40 int subscr;
41 register char *cp;
42 register char *zp = z;
43 register char *limit;
44
45 subscr = i - lb_a;
46 if (subscr < 0 || subscr > ub_a) {
47 ERROR("i = %D: Bad i to pack(a,i,z)\n", i);
48 return;
49 }
50 cp = &a[subscr * size_a];
51 limit = cp + size_z;
52 do {
53 *zp++ = *cp++;
54 } while (cp < limit);
55 }
56