Microsoft-3D-Movie-Maker/kauai/DOC/MEM.TXT

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/***************************************************************************
Memory Management API doc.
***************************************************************************/
/****************************************
Types
****************************************/
HQ
An opaque handle to a generic memory block.
Implementation is private.
HN
An operating system handle. On Mac, these are Handles.
On Win, they are HGLOBAL.
/****************************************
Constants
****************************************/
const byte kbGarbage;
New blocks are filled with this (if they are not zeroed)
const long kcbMax;
Maximum size of an HQ.
HQ hqNil;
pNil
hNil
It is legal to assume these are zero. Use hqNil to compare
against an explicit hq, pNil for pointers and hNil for any
other abstract handle.
fhqNil - default options
fhqClear - zero newly allocated memory
/****************************************
Routines
****************************************/
HQ HqAlloc(long cb, ushort grfhq);
Allocates an hq and optionally clears it.
void FreeHq(HQ hq);
Frees an hq. Accepts hqNil.
void FreePhq(HQ *phq);
Calls FreeHq on *phq and sets *phq to hqNil.
long CbOfHq(HQ hq);
Returns the size of the hq. This is guaranteed to be the
same as the cb passed to HqAlloc (or FResizePhq).
HQ HqCopyHq(HQ hq);
Duplicates the hq.
bool FResizePhq(HQ *phq, long cb, ushort grfhq);
Resizes *phq. The value of *phq may change.
void *PvLockHq(HQ hq);
Lock the hq and return a pointer to the data.
void UnlockHq(HQ hq);
Unlock the hq. Must balance a call to PvLockHq or LockHq.
void *QvFromHq(HQ hq);
Return a volatile pointer to the hq block.
/****************************************
Generic pointer arithmetic
****************************************/
void *PvAddBv(void *pv, long bv);
Add an offset to a pointer.
void *PvSubBv(void *pv, long bv);
Subtract an offset from a pointer.
long BvSubPvs(void *pv1, void *pv2)
Subtract two pointers to get the number of bytes between them.
/****************************************
Debug only API
****************************************/
void UnmarkAllHqs(void);
Clear the marks on all hq's.
void MarkHq(HQ hq);
Marks an hq.
void AssertUnmarkedHqs(void);
Asserts on any unmarked hqs.
void AssertHq(HQ hq);
Validate an hq. hq should not be nil.