1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1985-2011 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/*	Change discipline.
25**	dt :	dictionary
26**	disc :	discipline
27**
28**	Written by Kiem-Phong Vo (5/26/96)
29*/
30
31#if __STD_C
32static Void_t* dtmemory(Dt_t* dt,Void_t* addr,size_t size,Dtdisc_t* disc)
33#else
34static Void_t* dtmemory(dt, addr, size, disc)
35Dt_t* 		dt;	/* dictionary			*/
36Void_t* 	addr;	/* address to be manipulate	*/
37size_t		size;	/* size to obtain		*/
38Dtdisc_t* 	disc;	/* discipline			*/
39#endif
40{
41	if(addr)
42	{	if(size == 0)
43		{	free(addr);
44			return NIL(Void_t*);
45		}
46		else	return realloc(addr,size);
47	}
48	else	return size > 0 ? malloc(size) : NIL(Void_t*);
49}
50
51#if __STD_C
52Dtdisc_t* dtdisc(Dt_t* dt, Dtdisc_t* disc, int type)
53#else
54Dtdisc_t* dtdisc(dt,disc,type)
55Dt_t*		dt;
56Dtdisc_t*	disc;
57int		type;
58#endif
59{
60	reg Dtsearch_f	searchf;
61	reg Dtlink_t	*r, *t;
62	reg char*	k;
63	reg Dtdisc_t*	old;
64
65	if(!(old = dt->disc) )	/* initialization call from dtopen() */
66	{	dt->disc = disc;
67		if(!(dt->memoryf = disc->memoryf) )
68			dt->memoryf = dtmemory;
69		return disc;
70	}
71
72	if(!disc)	/* only want to know current discipline */
73		return old;
74
75	searchf = dt->meth->searchf;
76
77	UNFLATTEN(dt);
78
79	if(old->eventf && (*old->eventf)(dt,DT_DISC,(Void_t*)disc,old) < 0)
80		return NIL(Dtdisc_t*);
81
82	dt->disc = disc;
83	if(!(dt->memoryf = disc->memoryf) )
84		dt->memoryf = dtmemory;
85
86	if(dt->data->type&(DT_STACK|DT_QUEUE|DT_LIST))
87		goto done;
88	else if(dt->data->type&DT_BAG)
89	{	if(type&DT_SAMEHASH)
90			goto done;
91		else	goto dt_renew;
92	}
93	else if(dt->data->type&(DT_SET|DT_BAG))
94	{	if((type&DT_SAMEHASH) && (type&DT_SAMECMP))
95			goto done;
96		else	goto dt_renew;
97	}
98	else /*if(dt->data->type&(DT_OSET|DT_OBAG))*/
99	{	if(type&DT_SAMECMP)
100			goto done;
101	dt_renew:
102		r = dtflatten(dt);
103		dt->data->type &= ~DT_FLATTEN;
104		dt->data->here = NIL(Dtlink_t*);
105		dt->data->size = 0;
106
107		if(dt->data->type&(DT_SET|DT_BAG))
108		{	reg Dtlink_t	**s, **ends;
109			ends = (s = dt->data->htab) + dt->data->ntab;
110			while(s < ends)
111				*s++ = NIL(Dtlink_t*);
112		}
113
114		/* reinsert them */
115		while(r)
116		{	t = r->right;
117			if(!(type&DT_SAMEHASH))	/* new hash value */
118			{	k = (char*)_DTOBJ(r,disc->link);
119				k = _DTKEY((Void_t*)k,disc->key,disc->size);
120				r->hash = _DTHSH(dt,k,disc,disc->size);
121			}
122			(void)(*searchf)(dt,(Void_t*)r,DT_RENEW);
123			r = t;
124		}
125	}
126
127done:
128	return old;
129}
130