dlls/jscript/jsutils.c

   1 /*
   2  * Copyright 2008 Jacek Caban for CodeWeavers
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include "jscript.h"
  20
  21 #include "wine/debug.h"
  22
  23 WINE_DEFAULT_DEBUG_CHANNEL(jscript);
  24
  25 #define MIN_BLOCK_SIZE  128
  26
  27 static inline DWORD block_size(DWORD block)
  28 {
  29     return MIN_BLOCK_SIZE << block;
  30 }
  31
  32 void jsheap_init(jsheap_t *heap)
  33 {
  34     memset(heap, 0, sizeof(*heap));
  35     list_init(&heap->custom_blocks);
  36 }
  37
  38 void *jsheap_alloc(jsheap_t *heap, DWORD size)
  39 {
  40     struct list *list;
  41     void *tmp;
  42
  43     if(!heap->block_cnt) {
  44         if(!heap->blocks) {
  45             heap->blocks = heap_alloc(sizeof(void*));
  46             if(!heap->blocks)
  47                 return NULL;
  48         }
  49
  50         tmp = heap_alloc(block_size(0));
  51         if(!tmp)
  52             return NULL;
  53
  54         heap->blocks[0] = tmp;
  55         heap->block_cnt = 1;
  56     }
  57
  58     if(heap->offset + size < block_size(heap->last_block)) {
  59         tmp = ((BYTE*)heap->blocks[heap->last_block])+heap->offset;
  60         heap->offset += size;
  61         return tmp;
  62     }
  63
  64     if(size < block_size(heap->last_block+1)) {
  65         if(heap->last_block+1 == heap->block_cnt) {
  66             tmp = heap_realloc(heap->blocks, (heap->block_cnt+1)*sizeof(void*));
  67             if(!tmp)
  68                 return NULL;
  69             heap->blocks = tmp;
  70         }
  71
  72         tmp = heap_alloc(block_size(heap->block_cnt+1));
  73         if(!tmp)
  74             return NULL;
  75
  76         heap->blocks[heap->block_cnt++] = tmp;
  77
  78         heap->last_block++;
  79         heap->offset = size;
  80         return heap->blocks[heap->last_block];
  81     }
  82
  83     list = heap_alloc(size + sizeof(struct list));
  84     if(!list)
  85         return NULL;
  86
  87     list_add_head(&heap->custom_blocks, list);
  88     return list+1;
  89 }
  90
  91 void jsheap_clear(jsheap_t *heap)
  92 {
  93     struct list *tmp;
  94
  95     while((tmp = list_next(&heap->custom_blocks, &heap->custom_blocks))) {
  96         list_remove(tmp);
  97         heap_free(tmp);
  98     }
  99 }
 100
 101 void jsheap_free(jsheap_t *heap)
 102 {
 103     DWORD i;
 104
 105     jsheap_clear(heap);
 106
 107     for(i=0; i < heap->block_cnt; i++)
 108         heap_free(heap->blocks[i]);
 109     heap_free(heap->blocks);
 110
 111     jsheap_init(heap);
 112 }