firmware/include/lru.h

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  *
   9  * Copyright (C) 2003 Tat Tang
  10  *
  11  * All files in this archive are subject to the GNU General Public License.
  12  * See the file COPYING in the source tree root for full license agreement.
  13  *
  14  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  15  * KIND, either express or implied.
  16  *
  17  ****************************************************************************/
  18
  19 #ifndef LRU_H
  20 #define LRU_H
  21
  22 /*******************************************************************************
  23  * LRU manager
  24  ******************************************************************************/
  25 struct lru
  26 {
  27     short _head;
  28     short _tail;
  29     short _size;
  30     short _slot_size;
  31     void *_base;
  32 };
  33
  34 #define LRU_SLOT_OVERHEAD (2 * sizeof(short))
  35
  36 /* Create LRU list with specified size from buf. */
  37 void lru_create(struct lru* pl, void *buf, short size, short data_size);
  38 /* Touch an entry. Moves handle to back of LRU list */
  39 void lru_touch(struct lru* pl, short handle);
  40 /* Data */
  41 void *lru_data(struct lru* pl, short handle);
  42 /* Traverse lru-wise */
  43 void lru_traverse(struct lru* pl, void (*callback)(void* data));
  44
  45 #endif /* LRU_H */
  46