xref: /titanic_52/usr/src/contrib/ast/src/lib/libast/vmalloc/vmgetmem.c (revision 906afcb89d0412cc073b95c2d701a804a8cdb62c)
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	<vmalloc.h>
23 
24 /*
25  * vm open/close/resize - a handy default for discipline memory functions
26  *
27  *	vmgetmem(0,0,0)		open new region
28  *	vmgetmem(r,0,0)		free region
29  *	vmgetmem(r,0,n)		allocate n bytes initialized to 0
30  *	vmgetmem(r,p,0)		free p
31  *	vmgetmem(r,p,n)		realloc p to n bytes
32  *
33  * Written by Glenn S. Fowler.
34  */
35 
36 #if __STD_C
37 Void_t* vmgetmem(Vmalloc_t* vm, Void_t* data, size_t size)
38 #else
39 Void_t* vmgetmem(vm, data, size)
40 Vmalloc_t*	vm;
41 Void_t*		data;
42 size_t		size;
43 #endif
44 {
45 	if (!vm)
46 		return vmopen(Vmdcheap, Vmbest, 0);
47 	if (data || size)
48 		return vmresize(vm, data, size, VM_RSMOVE|VM_RSCOPY|VM_RSZERO);
49 	vmclose(vm);
50 	return 0;
51 }
52