mdw@git.distorted.org.uk Git - mLib/blob - arena.h

   1 /* -*-c-*-
   2  *
   3  * $Id: arena.h,v 1.1 2000/06/17 10:37:53 mdw Exp $
   4  *
   5  * Abstraction for memory allocation arenas
   6  *
   7  * (c) 2000 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of the mLib utilities library.
  13  *
  14  * mLib is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * mLib is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with mLib; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: arena.h,v $
  33  * Revision 1.1  2000/06/17 10:37:53  mdw
  34  * Basic arena management.
  35  *
  36  */
  37
  38 #ifndef MLIB_ARENA_H
  39 #define MLIB_ARENA_H
  40
  41 #ifdef __cplusplus
  42   extern "C" {
  43 #endif
  44
  45 /*----- Header files ------------------------------------------------------*/
  46
  47 #include <stdlib.h>
  48
  49 /*----- Data structures ---------------------------------------------------*/
  50
  51 /* --- An arena structure --- */
  52
  53 typedef struct arena {
  54   struct arena_ops *ops;
  55 } arena;
  56
  57 typedef struct arena_ops {
  58   void *(*alloc)(arena */*a*/, size_t /*sz*/);
  59   void *(*realloc)(arena */*a*/, void */*p*/, size_t /*sz*/);
  60   void (*free)(arena */*a*/, void */*p*/);
  61   void (*purge)(arena */*a*/);
  62 } arena_ops;
  63
  64 /*----- Global variables --------------------------------------------------*/
  65
  66 extern arena *arena_global;             /* Standard global arena */
  67 extern arena arena_stdlib;              /* Arena based on @malloc@/@free@ */
  68
  69 /*----- Functions provided ------------------------------------------------*/
  70
  71 /* --- @arena_fakerealloc@ --- *
  72  *
  73  * Arguments:   @arena *a@ = pointer to arena block
  74  *              @void *p@ = pointer to memory block to resize
  75  *              @size_t sz@ = size desired for the block
  76  *
  77  * Returns:     ---
  78  *
  79  * Use:         Standard fake @realloc@ function, for use if you don't
  80  *              support @realloc@ properly.
  81  */
  82
  83 extern void *arena_fakerealloc(arena */*a*/, void */*p*/, size_t /*sz*/);
  84
  85 /* --- Useful macros --- */
  86
  87 #define A_ALLOC(a, sz) (((a)->ops->alloc)((a), (sz)))
  88 #define A_REALLOC(a, p, sz) (((a)->ops->realloc)((a), (p), (sz)))
  89 #define A_FREE(a, p) (((a)->ops->free)((a), (p)))
  90
  91 /* --- Simple function equivalents --- */
  92
  93 extern void *a_alloc(arena */*a*/, size_t /*sz*/);
  94 extern void *a_realloc(arena */*a*/, void */*p*/, size_t /*sz*/);
  95 extern void a_free(arena */*a*/, void */*p*/);
  96
  97 /*----- That's all, folks -------------------------------------------------*/
  98
  99 #ifdef __cplusplus
 100   }
 101 #endif
 102
 103 #endif