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   1 /* -*-c-*-
   2  *
   3  * $Id: mparena.h,v 1.4 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Allocation and freeing of MP buffers
   6  *
   7  * (c) 1999 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb 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  * Catacomb 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 Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 #ifndef CATACOMB_MPARENA_H
  31 #define CATACOMB_MPARENA_H
  32
  33 #ifdef __cplusplus
  34   extern "C" {
  35 #endif
  36
  37 /*----- Header files ------------------------------------------------------*/
  38
  39 #include <mLib/arena.h>
  40
  41 #ifndef CATACOMB_MPW_H
  42 #  include "mpw.h"
  43 #endif
  44
  45 /*----- Data structures ---------------------------------------------------*/
  46
  47 /* --- @mparena_node@ --- *
  48  *
  49  * For internal use by the MP arena manager.  The free blocks are held in a
  50  * binary tree by size, held in the first digit of each vector.
  51  */
  52
  53 typedef struct mparena_node {
  54   struct mparena_node *left, *right;
  55   mpw *v;
  56 } mparena_node;
  57
  58 /* --- @mparena@ --- *
  59  *
  60  * The actual arena.
  61  */
  62
  63 typedef struct mparena {
  64   mparena_node *root;
  65   unsigned n;
  66   arena *a;
  67 } mparena;
  68
  69 /*----- Standard arenas ---------------------------------------------------*/
  70
  71 extern mparena mparena_global;
  72 #define MPARENA_GLOBAL (&mparena_global)
  73
  74 extern mparena mparena_secure;
  75 #define MPARENA_SECURE (&mparena_secure)
  76
  77 /*----- Functions provided ------------------------------------------------*/
  78
  79 /* --- @mparena_create@ --- *
  80  *
  81  * Arguments:   @mparena *a@ = pointer to arena block
  82  *
  83  * Returns:     ---
  84  *
  85  * Use:         Initializes an MP arena so that blocks can be allocated from
  86  *              it.
  87  */
  88
  89 extern void mparena_create(mparena */*a*/);
  90
  91 #define MPARENA_INIT { 0, 0, &arena_stdlib }
  92
  93 /* --- @mparena_setarena@ --- *
  94  *
  95  * Arguments:   @mparena *a@ = pointer to MP arena block
  96  *              @arena *aa@ = pointer to arena
  97  *
  98  * Returns:     ---
  99  *
 100  * Use:         Sets the underlying arena for an MP arena.
 101  */
 102
 103 extern void mparena_setarena(mparena */*a*/, arena */*aa*/);
 104
 105 /* --- @mparena_destroy@ --- *
 106  *
 107  * Arguments:   @mparena *a@ = pointer to arena block
 108  *
 109  * Returns:     ---
 110  *
 111  * Use:         Frees an MP arena, and all the vectors held within it.  The
 112  *              blocks which are currently allocated can be freed into some
 113  *              other MP arena, as long as the underlying arenas are the
 114  *              same.
 115  */
 116
 117 extern void mparena_destroy(mparena */*a*/);
 118
 119 /* --- @mparena_count@ --- *
 120  *
 121  * Arguments:   @mparena *a@ = pointer to arena block
 122  *
 123  * Returns:     Number of allocated blocks from this arena.
 124  *
 125  * Use:         Reports the number of blocks allocated from the arena and not
 126  *              yet freed.
 127  */
 128
 129 extern unsigned mparena_count(mparena */*a*/);
 130
 131 /* --- @mpalloc@ --- *
 132  *
 133  * Arguments:   @mparena *a@ = pointer to arena block
 134  *              @size_t sz@ = number of digits required
 135  *
 136  * Returns:     Pointer to a suitably sized block.
 137  *
 138  * Use:         Allocates a lump of data suitable for use as an array of MP
 139  *              digits.
 140  */
 141
 142 extern mpw *mpalloc(mparena */*a*/, size_t /*sz*/);
 143
 144 /* --- @mpfree@ --- *
 145  *
 146  * Arguments:   @mparena *a@ = pointer to arena block
 147  *              @mpw *v@ = pointer to allocated vector
 148  *
 149  * Returns:     ---
 150  *
 151  * Use:         Returns an MP vector to an arena.
 152  */
 153
 154 extern void mpfree(mparena */*a*/, mpw */*v*/);
 155
 156 /*----- That's all, folks -------------------------------------------------*/
 157
 158 #ifdef __cplusplus
 159   }
 160 #endif
 161
 162 #endif