xref: /illumos-gate/usr/src/contrib/ast/src/lib/libast/cdt/dtmethod.c (revision b30d193948be5a7794d7ae3ba0ed9c2f72c88e0f)
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 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
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 search method.
25 **
26 **	Written by Kiem-Phong Vo (05/25/96)
27 */
28 
29 #if __STD_C
dtmethod(Dt_t * dt,Dtmethod_t * meth)30 Dtmethod_t* dtmethod(Dt_t* dt, Dtmethod_t* meth)
31 #else
32 Dtmethod_t* dtmethod(dt, meth)
33 Dt_t*		dt;
34 Dtmethod_t*	meth;
35 #endif
36 {
37 	Dtlink_t	*list;
38 	Dtdisc_t	*disc = dt->disc;
39 	Dtmethod_t	*oldmt = dt->meth;
40 	Dtdata_t	*newdt, *olddt = dt->data;
41 
42 	if(!meth || meth == oldmt)
43 		return oldmt;
44 
45 	/* ask discipline if switching to new method is ok */
46 	if(disc->eventf && (*disc->eventf)(dt,DT_METH,(Void_t*)meth,disc) < 0)
47 		return NIL(Dtmethod_t*);
48 
49 	list = dtextract(dt); /* extract elements out of dictionary */
50 
51 	/* try to create internal structure for new method */
52 	if(dt->searchf == oldmt->searchf) /* ie, not viewpathing */
53 		dt->searchf = meth->searchf;
54 	dt->meth = meth;
55 	dt->data = NIL(Dtdata_t*);
56 	if((*dt->meth->eventf)(dt, DT_OPEN, NIL(Void_t*)) < 0 )
57 		newdt = NIL(Dtdata_t*);
58 	else	newdt = dt->data;
59 
60 	/* see what need to be done to data of the old method */
61 	if(dt->searchf == meth->searchf)
62 		dt->searchf = oldmt->searchf;
63 	dt->meth = oldmt;
64 	dt->data = olddt;
65 	if(newdt) /* switch was successful, remove old data */
66 	{	(void)(*dt->meth->eventf)(dt, DT_CLOSE, NIL(Void_t*));
67 
68 		if(dt->searchf == oldmt->searchf)
69 			dt->searchf = meth->searchf;
70 		dt->meth = meth;
71 		dt->data = newdt;
72 		dtrestore(dt, list);
73 		return oldmt;
74 	}
75 	else /* switch failed, restore dictionary to previous states */
76 	{	dtrestore(dt, list);
77 		return NIL(Dtmethod_t*);
78 	}
79 }
80 
81 /* customize certain actions in a container data structure */
dtcustomize(Dt_t * dt,int type,int action)82 int dtcustomize(Dt_t* dt, int type, int action)
83 {
84 	int	done = 0;
85 
86 	if((type&DT_SHARE) &&
87 	   (!dt->meth->eventf || (*dt->meth->eventf)(dt, DT_SHARE, (Void_t*)((long)action)) >= 0) )
88 	{	if(action <= 0 )
89 			dt->data->type &= ~DT_SHARE;
90 		else	dt->data->type |=  DT_SHARE;
91 		done |= DT_SHARE;
92 	}
93 
94 	if((type&DT_ANNOUNCE) &&
95 	   (!dt->meth->eventf || (*dt->meth->eventf)(dt, DT_ANNOUNCE, (Void_t*)((long)action)) >= 0) )
96 	{	if(action <= 0 )
97 			dt->data->type &= ~DT_ANNOUNCE;
98 		else	dt->data->type |=  DT_ANNOUNCE;
99 		done |= DT_ANNOUNCE;
100 	}
101 
102 	if((type&DT_OPTIMIZE) &&
103 	   (!dt->meth->eventf || (*dt->meth->eventf)(dt, DT_OPTIMIZE, (Void_t*)((long)action)) >= 0) )
104 		done |= DT_OPTIMIZE;
105 
106 	return done;
107 }
108