usr/src/lib/libast/common/vmalloc/vmdcheap.c

   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 #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