sys7.1-doc-wip/ProcessMgr/Zone32.h

71 lines
3.0 KiB
C

/*
File: Zone32.h
Contains: Information needed by 32-bit heap management routines. Mode non-specific
information is in Zone.h. 24-bit heap information is in Zone24.h.
Written by: David Harrison
Copyright: © 1989-1991 by Apple Computer, Inc., all rights reserved.
Change History (most recent first):
<0> x/xx/89 DFH New Today.
*/
/************************************************************************************
* Structure definition for heap block header
************************************************************************************/
typedef struct HeapBlock
{
unsigned char tagBC32; /* tag field (reloc/nonreloc/free) */
unsigned char MPtag32; /* master pointer tags (lock/purge/resource) */
unsigned char unused32; /* unused */
char SizeCor32; /* size correction */
unsigned long blkSize32; /* physical block size */
Handle handle32; /* handle32 depends on block type, as follows:
* non-relocatable: address of zone
* relocatable: offset from zone to master pointer
* free: reserved, always 0
*/
long blkData32[0]; /* data starts here */
} HeapBlock, *HeapBlockPtr;
/************************************************************************************
* Macros for basic block header field access.
* NOTE: Header access could be made faster/small by special-casing combinations of the
* fields in the first long word. I opted not to do this, though, so that the code in
* MemoryMgr24Patches.c and MemoryMgr32Patches.c matched as closely as possible.
************************************************************************************/
/* Characteristics */
#define SIZEOF_BLOCK_HEADER (12)
#define MIN_PHYSICAL_SIZE (SIZEOF_BLOCK_HEADER + MIN_LOGICAL_SIZE)
/* Field extraction and evaluation */
#define TAGBYTE(heapBlockPtr) ((heapBlockPtr)->tagBC32)
#define freeTagVal 0x00
#define nRelTagVal 0x40
#define relTagVal 0x80
#define SIZE_CORR(heapBlockPtr) ((heapBlockPtr)->SizeCor32)
#define BLOCK_SIZE(heapBlockPtr) ((heapBlockPtr)->blkSize32)
#define BLOCK_HANDLE(heapBlockPtr) ((heapBlockPtr)->handle32)
#define BLOCK_DATA(heapBlockPtr) ((heapBlockPtr)->blkData32)
#define MP_TAGBYTE(heapBlockPtr) ((heapBlockPtr)->MPtag32)
#define resourceMPTagFlag 0x20
#define purgeableMPTagFlag 0x40
#define lockedMPTagFlag 0x80
/************************************************************************************
* Compound macros for block header field access.
************************************************************************************/
#define CLEAR_BLOCK_ATTRS(heapBlockPtr) (*((long *) (heapBlockPtr)) = 0)
#define IS_FREE_BLOCK(heapBlockPtr) (TAGBYTE(heapBlockPtr) == freeTagVal)
#define IS_NOT_FREE_BLOCK(heapBlockPtr) (TAGBYTE(heapBlockPtr) != freeTagVal)
#define IS_NRELOC_BLOCK(heapBlockPtr) (TAGBYTE(heapBlockPtr) == nRelTagVal)
#define IS_RELOC_BLOCK(heapBlockPtr) (TAGBYTE(heapBlockPtr) == relTagVal)
#define IS_LOCKED_RELOC_BLOCK(heapBlockPtr,zonePtr) ((MP_TAGBYTE(heapBlockPtr) & lockedMPTagFlag) != 0)