firmware/include/lru.h

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  *
   9  * Copyright (C) 2003 Tat Tang
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  17  * KIND, either express or implied.
  18  *
  19  ****************************************************************************/
  20
  21 #ifndef LRU_H
  22 #define LRU_H
  23
  24 /*******************************************************************************
  25  * LRU manager
  26  ******************************************************************************/
  27 struct lru
  28 {
  29     short _head;
  30     short _tail;
  31     short _size;
  32     short _slot_size;
  33     void *_base;
  34 };
  35
  36 #define LRU_SLOT_OVERHEAD (2 * sizeof(short))
  37
  38 /* Create LRU list with specified size from buf. */
  39 void lru_create(struct lru* pl, void *buf, short size, short data_size);
  40 /* Touch an entry. Moves handle to back of LRU list */
  41 void lru_touch(struct lru* pl, short handle);
  42 /* Data */
  43 void *lru_data(struct lru* pl, short handle);
  44 /* Traverse lru-wise */
  45 void lru_traverse(struct lru* pl, void (*callback)(void* data));
  46
  47 #endif /* LRU_H */
  48