gemrb/plugins/Core/Cache.h

   1 /* GemRB - Infinity Engine Emulator
   2  * Copyright (C) 2003 |Avenger|
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program 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
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  17  *
  18  *
  19  */
  20
  21 #ifndef CACHE_H
  22 #define CACHE_H
  23
  24 #include <ctype.h>
  25 #include <cstring>
  26 #include "win32def.h"
  27 #include "globals.h"
  28 /////////////////////////////////////////////////////////////////////////////
  29 // Cache<ieResRef, void*>
  30
  31 #define KEYSIZE 8
  32
  33 #ifndef ReleaseFun
  34 typedef void (*ReleaseFun)(void *);
  35 #endif
  36
  37 class Cache
  38 {
  39 protected:
  40         // Association
  41         struct MyAssoc {
  42                 MyAssoc* pNext;
  43                 MyAssoc** pPrev;
  44                 char key[KEYSIZE]; //not ieResRef!
  45                 ieDword nRefCount;
  46                 void* data;
  47         };
  48         struct MemBlock {
  49                 MemBlock* pNext;
  50         };
  51
  52 public:
  53         // Construction
  54         Cache(int nBlockSize = 10, int nHashTableSize = 129);
  55
  56         // Attributes
  57         // number of elements
  58         inline int GetCount() const
  59         {
  60                 return m_nCount;
  61         }
  62         inline bool IsEmpty() const
  63         {
  64                 return m_nCount==0;
  65         }
  66         // Lookup
  67         void *GetResource(const ieResRef key);
  68         // Operations
  69         bool SetAt(const ieResRef key, void *rValue);
  70         // decreases refcount or drops data
  71         //if name is supplied it is faster, it will use rValue to validate the request
  72         int DecRef(void *rValue, const ieResRef name, bool free);
  73         int RefCount(const ieResRef key) const;
  74         void RemoveAll(ReleaseFun fun);//removes all refcounts
  75         void Cleanup();  //removes only zero refcounts
  76         void InitHashTable(unsigned int hashSize, bool bAllocNow = true);
  77
  78         // Implementation
  79 protected:
  80         MyAssoc** m_pHashTable;
  81         unsigned int m_nHashTableSize;
  82         int m_nCount;
  83         MyAssoc* m_pFreeList;
  84         MemBlock* m_pBlocks;
  85         int m_nBlockSize;
  86
  87         Cache::MyAssoc* NewAssoc();
  88         void FreeAssoc(Cache::MyAssoc*);
  89         Cache::MyAssoc* GetAssocAt(const ieResRef) const;
  90         Cache::MyAssoc *GetNextAssoc(Cache::MyAssoc * rNextPosition) const;
  91         unsigned int MyHashKey(const ieResRef) const;
  92
  93 public:
  94         ~Cache();
  95 };
  96
  97 #endif //CACHE_H