xref: /titanic_41/usr/src/lib/libast/common/cdt/dtflatten.c (revision 3fb517f786391b507780c78aabb8d98bfea9efe9)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #include	"dthdr.h"
23 
24 /*	Flatten a dictionary into a linked list.
25 **	This may be used when many traversals are likely.
26 **
27 **	Written by Kiem-Phong Vo (5/25/96).
28 */
29 
30 #if __STD_C
31 Dtlink_t* dtflatten(Dt_t* dt)
32 #else
33 Dtlink_t* dtflatten(dt)
34 Dt_t*	dt;
35 #endif
36 {
37 	reg Dtlink_t	*t, *r, *list, *last, **s, **ends;
38 
39 	/* already flattened */
40 	if(dt->data->type&DT_FLATTEN )
41 		return dt->data->here;
42 
43 	list = last = NIL(Dtlink_t*);
44 	if(dt->data->type&(DT_SET|DT_BAG))
45 	{	for(ends = (s = dt->data->htab) + dt->data->ntab; s < ends; ++s)
46 		{	if((t = *s) )
47 			{	if(last)
48 					last->right = t;
49 				else	list = last = t;
50 				while(last->right)
51 					last = last->right;
52 				*s = last;
53 			}
54 		}
55 	}
56 	else if(dt->data->type&(DT_LIST|DT_STACK|DT_QUEUE) )
57 		list = dt->data->head;
58 	else if((r = dt->data->here) ) /*if(dt->data->type&(DT_OSET|DT_OBAG))*/
59 	{	while((t = r->left) )
60 			RROTATE(r,t);
61 		for(list = last = r, r = r->right; r; last = r, r = r->right)
62 		{	if((t = r->left) )
63 			{	do	RROTATE(r,t);
64 				while((t = r->left) );
65 
66 				last->right = r;
67 			}
68 		}
69 	}
70 
71 	dt->data->here = list;
72 	dt->data->type |= DT_FLATTEN;
73 
74 	return list;
75 }
76