xref: /titanic_41/usr/src/lib/libast/common/vmalloc/vmdcheap.c (revision 36e852a172cba914383d7341c988128b2c667fbd)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2009 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 #if defined(_UWIN) && defined(_BLD_ast)
23 
24 void _STUB_vmdcheap(){}
25 
26 #else
27 
28 #include	"vmhdr.h"
29 
30 /*	A discipline to get memory from the heap.
31 **
32 **	Written by Kiem-Phong Vo, kpv@research.att.com, 01/16/94.
33 */
34 #if __STD_C
35 static Void_t* heapmem(Vmalloc_t* vm, Void_t* caddr,
36 			size_t csize, size_t nsize,
37 			Vmdisc_t* disc)
38 #else
39 static Void_t* heapmem(vm, caddr, csize, nsize, disc)
40 Vmalloc_t*	vm;	/* region doing allocation from 	*/
41 Void_t*		caddr;	/* current low address			*/
42 size_t		csize;	/* current size				*/
43 size_t		nsize;	/* new size				*/
44 Vmdisc_t*	disc;	/* discipline structure			*/
45 #endif
46 {
47 	NOTUSED(vm);
48 	NOTUSED(disc);
49 
50 	if(csize == 0)
51 		return vmalloc(Vmheap,nsize);
52 	else if(nsize == 0)
53 		return vmfree(Vmheap,caddr) >= 0 ? caddr : NIL(Void_t*);
54 	else	return vmresize(Vmheap,caddr,nsize,0);
55 }
56 
57 static Vmdisc_t _Vmdcheap = { heapmem, NIL(Vmexcept_f), 0 };
58 __DEFINE__(Vmdisc_t*,Vmdcheap,&_Vmdcheap);
59 
60 #ifdef NoF
61 NoF(vmdcheap)
62 #endif
63 
64 #endif
65