include/shm_fragment.h

   1 /***************************************************************************
   2  * Copyright 1995, Technion, Israel Institute of Technology
   3  * Electrical Eng, Software Lab.
   4  * Author:    Michael Veksler.
   5  ***************************************************************************
   6  * File:      shm_fragment.h
   7  * Purpose:   Data fragments and free list items. Allocate and free blocks.
   8  ***************************************************************************
   9  */
  10 #ifndef __WINE_SHM_FRAGMENT_H
  11 #define __WINE_SHM_FRAGMENT_H
  12
  13 #include "shm_block.h"
  14
  15 #define NIL ((int) 0)
  16 /* memory fragment: used or free (when free - it's an item of "free list",
  17  * when allocated it contains the data, and it's size)
  18  */
  19 struct shm_fragment {
  20         int size;               /* fragment's size */
  21
  22         /* The type of info depends on fragment's status (free/allocated) */
  23         union info {
  24                 int next;       /* next free fragment */
  25                 char data[1];   /* the data */
  26         } info;
  27 };
  28
  29 /* setup first item in the free list */
  30 void shm_FragmentInit(struct shm_block *block,REL_PTR first,int size);
  31
  32 /* allocate shm fragment. return: offset to data in fragment, or NULL */
  33 REL_PTR shm_FragmentAlloc(struct shm_block *block, int size);
  34
  35 /* like shm_FragmentAlloc, returns pointer instead of offset */
  36 char *shm_FragPtrAlloc(struct shm_block *block, int size);
  37
  38 /* free shm fragment - according to offset */
  39 void shm_FragmentFree(struct shm_block *block, int ofs);
  40
  41 /* free shm fragment - according to pointer */
  42 void shm_FragPtrFree(struct shm_block *block, void *ptr);
  43
  44 /* This is used for debugging only */
  45 void shm_print_free_list(struct shm_block *block);
  46
  47 #endif /* __WINE_SHM_FRAGMENT_H */