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/*
* alloc.h
* Copyright (C) 1998-1999 Patrick Alken
*
* $Id: alloc.h,v 1.2 2001/06/04 09:07:56 kreator Exp $
*/
#ifndef INCLUDED_alloc_h
#define INCLUDED_alloc_h
#ifndef INCLUDED_sys_types_h
#include <sys/types.h> /* size_t */
#define INCLUDED_sys_types_h
#endif
#ifndef INCLUDED_stdlib_h
#include <stdlib.h> /* free() */
#define INCLUDED_stdlib_h
#endif
#ifndef INCLUDED_config_h
#include "config.h" /* BLOCK_ALLOCATION */
#define INCLUDED_config_h
#endif
#ifdef BLOCK_ALLOCATION
/* structure definition for a sub block in a preallocated heap */
typedef struct sBlock
{
struct sBlock *next; /* next sub block in our heap */
void *first; /* pointer to first element in sub block */
void *last; /* pointer to last element in sub block */
int FreeElements; /* number of unused elements in sub block */
/*
* This is the pointer to the last used element in the block,
* meaning every slot between 'LastUsedSlot' and 'last', will
* be unused. This is needed for BlockSubFree().
* Normally, (Heap->ElementsPerBlock - Block->FreeElements)
* would be the same thing, but if middle elements are deleted,
* Block->FreeElements would increase, while the last used
* element in the block would remain the same, so we need a
* separate pointer to keep track.
*/
void *LastUsedSlot;
/*
* SlotHoles is an array of pointers to all of the
* "holes" in the sub block; when an element is deleted,
* its pointer is added to this array so the next time
* we add an element, we know where to fill in the hole
*/
void **SlotHoles;
int LastSlotHole; /* number of used indices in SlotHoles[] */
} SubBlock;
/* structure definition for a preallocated heap of memory */
typedef struct BlockHeap
{
SubBlock *base; /* first sub block in our heap */
int ElementSize; /* size of each element */
int ElementsPerBlock; /* number of elements in each sub block */
int NumSubBlocks; /* number of sub blocks we have allocated */
int FreeElements; /* number of unused elements in all blocks */
} Heap;
/*
* Prototypes
*/
Heap *HeapCreate(size_t elementsize, int numperblock);
void *BlockSubAllocate(Heap *heapptr);
void BlockSubFree(Heap *heapptr, void *element);
void InitHeaps();
#endif /* BLOCK_ALLOCATION */
void *MyMalloc(size_t bytes);
void *MyRealloc(void *oldptr, size_t bytes);
char *MyStrdup(const char *str);
void MyFree(void *ptr);
void OutOfMem();
/*
* External declarations
*/
#ifdef BLOCK_ALLOCATION
extern Heap *ClientHeap;
extern Heap *ChannelHeap;
extern Heap *ServerHeap;
#endif /* BLOCK_ALLOCATION */
#endif /* INCLUDED_alloc_h */
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