windows-nt/Source/XPSP1/NT/drivers/video/ms/w32/disp/heap.c
2020-09-26 16:20:57 +08:00

1765 lines
54 KiB
C

/******************************Module*Header*******************************\
* Module Name: heap.c
*
* This module contains the routines for a 2-d heap. It is used primarily
* for allocating space for device-format-bitmaps in off-screen memory.
*
* Off-screen bitmaps are a big deal on NT because:
*
* 1) It reduces the working set. Any bitmap stored in off-screen
* memory is a bitmap that isn't taking up space in main memory.
*
* 2) There is a speed win by using the accelerator hardware for
* drawing, in place of NT's GDI code. NT's GDI is written entirely
* in 'C++' and perhaps isn't as fast as it could be.
*
* 3) It leads naturally to nifty tricks that can take advantage of
* the hardware, such as MaskBlt support and cheap double buffering
* for OpenGL.
*
* The heap algorithm employed herein attempts to solve an unsolvable
* problem: the problem of keeping arbitrary sized bitmaps as packed as
* possible in a 2-d space, when the bitmaps can come and go at random.
*
* This problem is due entirely to the nature of the hardware for which this
* driver is written: the hardware treats everything as 2-d quantities. If
* the hardware bitmap pitch could be changed so that the bitmaps could be
* packed linearly in memory, the problem would be infinitely easier (it is
* much easier to track the memory, and the accelerator can be used to re-pack
* the heap to avoid segmentation).
*
* If your hardware can treat bitmaps as one dimensional quantities (as can
* the XGA and ATI), by all means please implement a new off-screen heap.
*
* When the heap gets full, old allocations will automatically be punted
* from off-screen and copied to DIBs, which we'll let GDI draw on.
*
* Note that this heap manages reverse-L shape off-screen memory
* configurations (where the scan pitch is longer than the visible screen,
* such as happens at 800x600 when the scan length must be a multiple of
* 1024).
*
* NOTE: All heap operations must be done under some sort of synchronization,
* whether it's controlled by GDI or explicitly by the driver. All
* the routines in this module assume that they have exclusive access
* to the heap data structures; multiple threads partying in here at
* the same time would be a Bad Thing. (By default, GDI does NOT
* synchronize drawing on device-created bitmaps.)
*
* Copyright (c) 1993-1996 Microsoft Corporation
\**************************************************************************/
#include "precomp.h"
#define OH_ALLOC_SIZE 4000 // Do all memory allocations in 4k chunks
#define OH_QUANTUM 4 // The minimum dimension of an allocation
#define CXCY_SENTINEL 0x7fffffff // The sentinel at the end of the available
// list has this very large 'cxcy' value
// This macro results in the available list being maintained with a
// cx-major, cy-minor sort:
#define CXCY(cx, cy) (((cx) << 16) | (cy))
/******************************Public*Routine******************************\
* OH* pohNewNode
*
* Allocates a basic memory unit in which we'll pack our data structures.
*
* Since we'll have a lot of OH nodes, most of which we will be
* occasionally traversing, we do our own memory allocation scheme to
* keep them densely packed in memory.
*
* It would be the worst possible thing for the working set to simply
* call EngAllocMem(sizeof(OH)) every time we needed a new node. There
* would be no locality; OH nodes would get scattered throughout memory,
* and as we traversed the available list for one of our allocations,
* it would be far more likely that we would hit a hard page fault.
\**************************************************************************/
OH* pohNewNode(
PDEV* ppdev)
{
LONG i;
LONG cOhs;
OHALLOC* poha;
OH* poh;
if (ppdev->heap.pohFreeList == NULL)
{
// We zero-init to initialize all the OH flags, and to help in
// debugging (we can afford to do this since we'll be doing this
// very infrequently):
poha = EngAllocMem(FL_ZERO_MEMORY, OH_ALLOC_SIZE, ALLOC_TAG);
if (poha == NULL)
return(NULL);
// Insert this OHALLOC at the begining of the OHALLOC chain:
poha->pohaNext = ppdev->heap.pohaChain;
ppdev->heap.pohaChain = poha;
// This has a '+ 1' because OHALLOC includes an extra OH in its
// structure declaration:
cOhs = (OH_ALLOC_SIZE - sizeof(OHALLOC)) / sizeof(OH) + 1;
// The big OHALLOC allocation is simply a container for a bunch of
// OH data structures in an array. The new OH data structures are
// linked together and added to the OH free list:
poh = &poha->aoh[0];
for (i = cOhs - 1; i != 0; i--)
{
poh->pohNext = poh + 1;
poh = poh + 1;
}
poh->pohNext = NULL;
ppdev->heap.pohFreeList = &poha->aoh[0];
}
poh = ppdev->heap.pohFreeList;
ppdev->heap.pohFreeList = poh->pohNext;
return(poh);
}
/******************************Public*Routine******************************\
* VOID vOhFreeNode
*
* Frees our basic data structure allocation unit by adding it to a free
* list.
*
\**************************************************************************/
VOID vOhFreeNode(
PDEV* ppdev,
OH* poh)
{
if (poh == NULL)
return;
poh->pohNext = ppdev->heap.pohFreeList;
ppdev->heap.pohFreeList = poh;
poh->ohState = -1;
}
/******************************Public*Routine******************************\
* VOID vCalculateMaximumNonPermanent
*
* Traverses the list of in-use and available rectangles to find the one
* with the maximal area.
*
\**************************************************************************/
VOID vCalculateMaximumNonPermanent(
PDEV* ppdev)
{
OH* poh;
OH* pohSentinel;
LONG lArea;
LONG lMaxArea;
LONG cxMax;
LONG cyMax;
LONG i;
lMaxArea = 0;
cxMax = 0;
cyMax = 0;
// First time through, loop through the list of free available
// rectangles:
pohSentinel = &ppdev->heap.ohFree;
for (i = 2; i != 0; i--)
{
for (poh = pohSentinel->pohNext; poh != pohSentinel; poh = poh->pohNext)
{
ASSERTDD(poh->ohState != OH_PERMANENT,
"Permanent node in free or discardable list");
// We don't have worry about this multiply overflowing
// because we are dealing in physical screen coordinates,
// which will probably never be more than 15 bits:
lArea = poh->cx * poh->cy;
if (lArea > lMaxArea)
{
cxMax = poh->cx;
cyMax = poh->cy;
lMaxArea = lArea;
}
}
// Second time through, loop through the list of discardable
// rectangles:
pohSentinel = &ppdev->heap.ohDiscardable;
}
// All that we are interested in is the dimensions of the rectangle
// that has the largest possible available area (and remember that
// there might not be any possible available area):
ppdev->heap.cxMax = cxMax;
ppdev->heap.cyMax = cyMax;
}
/******************************Public*Routine******************************\
* OH* pohFree
*
* Frees an off-screen heap allocation. The free space will be combined
* with any adjacent free spaces to avoid segmentation of the 2-d heap.
*
* Note: A key idea here is that the data structure for the upper-left-
* most node must be kept at the same physical CPU memory so that
* adjacency links are kept correctly (when two free spaces are
* merged, the lower or right node can be freed).
*
\**************************************************************************/
OH* pohFree(
PDEV* ppdev,
OH* poh)
{
ULONG cxcy;
OH* pohBeside;
OH* pohNext;
OH* pohPrev;
OHSTATE oldState;
if (poh == NULL)
return(NULL);
DISPDBG((2, "Freeing %li x %li at (%li, %li)",
poh->cx, poh->cy, poh->x, poh->y));
#if DEBUG_HEAP
{
RECTL rclBitmap;
RBRUSH_COLOR rbc;
LONG xOffset;
LONG yOffset;
LONG xyOffset;
rclBitmap.left = poh->x;
rclBitmap.top = poh->y;
rclBitmap.right = poh->x + poh->cx;
rclBitmap.bottom = poh->y + poh->cy;
xOffset = ppdev->xOffset;
yOffset = ppdev->yOffset;
xyOffset = ppdev->xyOffset;
ppdev->xOffset = 0;
ppdev->yOffset = 0;
ppdev->xyOffset = 0;
ppdev->pfnFillSolid(ppdev, 1, &rclBitmap, 0x0, rbc, NULL);
ppdev->xOffset = xOffset;
ppdev->yOffset = yOffset;
ppdev->xyOffset = xyOffset;
}
#endif
oldState = poh->ohState;
if (oldState != OH_DISCARDABLE)
{
// We can remove the 'reserved' status unless we are merely
// deleting a discardable rectangle that was temporarily
// placed in a reserve rectangle:
poh->cxReserved = 0;
poh->cyReserved = 0;
}
// Update the uniqueness to show that space has been freed, so that
// we may decide to see if some DIBs can be moved back into off-screen
// memory:
ppdev->iHeapUniq++;
MergeLoop:
// Try merging with the right sibling:
pohBeside = poh->pohRight;
if ((poh->cxReserved != poh->cx) &&
(pohBeside->ohState == OH_FREE) &&
(pohBeside->cy == poh->cy) &&
(pohBeside->pohUp == poh->pohUp) &&
(pohBeside->pohDown == poh->pohDown) &&
(pohBeside->pohRight->pohLeft != pohBeside))
{
// Add the right rectangle to ours:
poh->cx += pohBeside->cx;
poh->pohRight = pohBeside->pohRight;
// Remove 'pohBeside' from the free list and free it:
pohBeside->pohNext->pohPrev = pohBeside->pohPrev;
pohBeside->pohPrev->pohNext = pohBeside->pohNext;
vOhFreeNode(ppdev, pohBeside);
goto MergeLoop;
}
// Try merging with the lower sibling:
pohBeside = poh->pohDown;
if ((poh->cyReserved != poh->cy) &&
(pohBeside->ohState == OH_FREE) &&
(pohBeside->cx == poh->cx) &&
(pohBeside->pohLeft == poh->pohLeft) &&
(pohBeside->pohRight == poh->pohRight) &&
(pohBeside->pohDown->pohUp != pohBeside))
{
poh->cy += pohBeside->cy;
poh->pohDown = pohBeside->pohDown;
pohBeside->pohNext->pohPrev = pohBeside->pohPrev;
pohBeside->pohPrev->pohNext = pohBeside->pohNext;
vOhFreeNode(ppdev, pohBeside);
goto MergeLoop;
}
// Don't do any more merge this rectangle into anything to the
// top or to the left if it's reserved:
if (!poh->cxReserved)
{
// Try merging with the left sibling:
pohBeside = poh->pohLeft;
if ((pohBeside->cxReserved != pohBeside->cx) &&
(pohBeside->ohState == OH_FREE) &&
(pohBeside->cy == poh->cy) &&
(pohBeside->pohUp == poh->pohUp) &&
(pohBeside->pohDown == poh->pohDown) &&
(pohBeside->pohRight == poh) &&
(poh->pohRight->pohLeft != poh))
{
// We add our rectangle to the one to the left:
pohBeside->cx += poh->cx;
pohBeside->pohRight = poh->pohRight;
// Remove 'poh' from whatever list it was in (if we were
// asked to free a 'permanent' node, it will have been in
// the permanent list) and free it:
poh->pohNext->pohPrev = poh->pohPrev;
poh->pohPrev->pohNext = poh->pohNext;
vOhFreeNode(ppdev, poh);
poh = pohBeside;
goto MergeLoop;
}
// Try merging with the upper sibling:
pohBeside = poh->pohUp;
if ((pohBeside->cyReserved != pohBeside->cy) &&
(pohBeside->ohState == OH_FREE) &&
(pohBeside->cx == poh->cx) &&
(pohBeside->pohLeft == poh->pohLeft) &&
(pohBeside->pohRight == poh->pohRight) &&
(pohBeside->pohDown == poh) &&
(poh->pohDown->pohUp != poh))
{
pohBeside->cy += poh->cy;
pohBeside->pohDown = poh->pohDown;
poh->pohNext->pohPrev = poh->pohPrev;
poh->pohPrev->pohNext = poh->pohNext;
vOhFreeNode(ppdev, poh);
poh = pohBeside;
goto MergeLoop;
}
}
// Remove this node from whatever list it's in:
poh->pohNext->pohPrev = poh->pohPrev;
poh->pohPrev->pohNext = poh->pohNext;
cxcy = CXCY(poh->cx, poh->cy);
// Insert the node, in order, into the free list:
pohNext = ppdev->heap.ohFree.pohNext;
while (pohNext->cxcy < cxcy)
{
pohNext = pohNext->pohNext;
}
pohPrev = pohNext->pohPrev;
pohPrev->pohNext = poh;
pohNext->pohPrev = poh;
poh->pohPrev = pohPrev;
poh->pohNext = pohNext;
poh->cxcy = cxcy;
poh->ohState = OH_FREE;
if (oldState == OH_PERMANENT)
{
// Removing the permanent entry means that we may be able to
// enlarge the maximum possible rectangle we can allow:
vCalculateMaximumNonPermanent(ppdev);
}
// Return the node pointer for the new and improved available rectangle:
return(poh);
}
/******************************Public*Routine******************************\
* BOOL bDiscardEverythingInRectangle
*
* Throws out of the heap any discardable bitmaps that intersect with the
* specified rectangle.
*
\**************************************************************************/
BOOL bDiscardEverythingInRectangle(
PDEV* ppdev,
LONG x,
LONG y,
LONG cx,
LONG cy)
{
BOOL bRet;
OH* poh;
OH* pohNext;
bRet = TRUE; // Assume success
poh = ppdev->heap.ohDiscardable.pohNext;
while (poh != &ppdev->heap.ohDiscardable)
{
ASSERTDD(poh->ohState == OH_DISCARDABLE,
"Non-discardable node in discardable list");
pohNext = poh->pohNext;
if ((poh->x < x + cx) &&
(poh->y < y + cy) &&
(poh->x + poh->cx > x) &&
(poh->y + poh->cy > y))
{
// The two rectangles intersect. Give the boot to the
// discardable bitmap:
if (!pohMoveOffscreenDfbToDib(ppdev, poh))
bRet = FALSE;
}
poh = pohNext;
}
return(bRet);
}
/******************************Public*Routine******************************\
* BOOL bFreeRightAndBottomSpace
*
* Given a free off-screen rectangle, allocates the upper-left part of
* the rectangle to hold the allocation request, and puts the two rectangles
* comprising the unused right and bottom portions on the free list.
*
\**************************************************************************/
BOOL bFreeRightAndBottomSpace(
PDEV* ppdev,
OH* pohThis,
LONG cxThis,
LONG cyThis,
BOOL bQuantum) // Set if inifitely small allocations should be
// allowed
{
ULONG cxcy; // Temporary versions
OH* pohNext;
OH* pohPrev;
LONG cxRem;
LONG cyRem;
OH* pohBelow;
LONG cxBelow;
LONG cyBelow;
OH* pohBeside;
LONG cxBeside;
LONG cyBeside;
LONG cQuantum;
// We're going to use the upper-left corner of our given rectangle,
// and divide the unused remainder into two rectangles which will
// go on the free list.
// Compute the width of the unused rectangle to the right, and the
// height of the unused rectangle below:
cyRem = pohThis->cy - cyThis;
cxRem = pohThis->cx - cxThis;
// Given finite area, we wish to find the two rectangles that are
// most square -- i.e., the arrangement that gives two rectangles
// with the least perimiter:
cyBelow = cyRem;
cxBeside = cxRem;
if (cxRem <= cyRem)
{
cxBelow = cxThis + cxRem;
cyBeside = cyThis;
}
else
{
cxBelow = cxThis;
cyBeside = cyThis + cyRem;
}
// If 'bQuantum' is set, we only make new available rectangles of
// the unused right and bottom portions if they're greater in
// dimension than OH_QUANTUM (it hardly makes sense to do the
// book-work to keep around a 2-pixel wide available space, for
// example):
cQuantum = (bQuantum) ? 1 : OH_QUANTUM;
pohBeside = NULL;
if (cxBeside >= cQuantum)
{
pohBeside = pohNewNode(ppdev);
if (pohBeside == NULL)
return(FALSE);
}
pohBelow = NULL;
if (cyBelow >= cQuantum)
{
pohBelow = pohNewNode(ppdev);
if (pohBelow == NULL)
{
vOhFreeNode(ppdev, pohBeside);
return(FALSE);
}
// Insert this rectangle into the available list (which is
// sorted on ascending cxcy):
cxcy = CXCY(cxBelow, cyBelow);
pohNext = ppdev->heap.ohFree.pohNext;
while (pohNext->cxcy < cxcy)
{
pohNext = pohNext->pohNext;
}
pohPrev = pohNext->pohPrev;
pohPrev->pohNext = pohBelow;
pohNext->pohPrev = pohBelow;
pohBelow->pohPrev = pohPrev;
pohBelow->pohNext = pohNext;
// Now update the adjacency information:
pohBelow->pohLeft = pohThis->pohLeft;
pohBelow->pohUp = pohThis;
pohBelow->pohRight = pohThis->pohRight;
pohBelow->pohDown = pohThis->pohDown;
// Update the rest of the new node information:
pohBelow->cxReserved = 0;
pohBelow->cyReserved = 0;
pohBelow->cxcy = cxcy;
pohBelow->ohState = OH_FREE;
pohBelow->x = pohThis->x;
pohBelow->y = pohThis->y + cyThis;
pohBelow->xy = ((ppdev->cBpp * pohBelow->x) +
(pohBelow->y * ppdev->lDelta));
pohBelow->cx = cxBelow;
pohBelow->cy = cyBelow;
// Modify the current node to reflect the changes we've made:
pohThis->cy = cyThis;
}
if (cxBeside >= cQuantum)
{
// Insert this rectangle into the available list (which is
// sorted on ascending cxcy):
cxcy = CXCY(cxBeside, cyBeside);
pohNext = ppdev->heap.ohFree.pohNext;
while (pohNext->cxcy < cxcy)
{
pohNext = pohNext->pohNext;
}
pohPrev = pohNext->pohPrev;
pohPrev->pohNext = pohBeside;
pohNext->pohPrev = pohBeside;
pohBeside->pohPrev = pohPrev;
pohBeside->pohNext = pohNext;
// Now update the adjacency information:
pohBeside->pohUp = pohThis->pohUp;
pohBeside->pohLeft = pohThis;
pohBeside->pohDown = pohThis->pohDown;
pohBeside->pohRight = pohThis->pohRight;
// Update the rest of the new node information:
pohBeside->cxReserved = 0;
pohBeside->cyReserved = 0;
pohBeside->cxcy = cxcy;
pohBeside->ohState = OH_FREE;
pohBeside->x = pohThis->x + cxThis;
pohBeside->y = pohThis->y;
pohBeside->xy = ((ppdev->cBpp * pohBeside->x) +
(pohBeside->y * ppdev->lDelta));
pohBeside->cx = cxBeside;
pohBeside->cy = cyBeside;
// Modify the current node to reflect the changes we've made:
pohThis->cx = cxThis;
}
if (pohBelow != NULL)
{
pohThis->pohDown = pohBelow;
if ((pohBeside != NULL) && (cyBeside == pohThis->cy))
pohBeside->pohDown = pohBelow;
}
if (pohBeside != NULL)
{
pohThis->pohRight = pohBeside;
if ((pohBelow != NULL) && (cxBelow == pohThis->cx))
pohBelow->pohRight = pohBeside;
}
pohThis->cxcy = CXCY(pohThis->cx, pohThis->cy);
return(TRUE);
}
/******************************Public*Routine******************************\
* OH* pohMakeRoomAtLocation
*
* Attempts to allocate a rectangle at a specific position.
*
\**************************************************************************/
OH* pohMakeRoomAtLocation(
PDEV* ppdev,
POINTL* pptl, // Requested position for the rectangle
LONG cxThis, // Width of rectangle to be allocated
LONG cyThis, // Height of rectangle to be allocated
FLONG floh) // Allocation flags
{
OH* poh;
OH* pohTop;
OH* pohLeft;
LONG cxLeft;
LONG cyTop;
OH* pohRight;
if (!(floh & FLOH_ONLY_IF_ROOM))
{
// First off, discard any bitmaps that overlap the requested
// rectangle, assuming we're allowed to:
if (!bDiscardEverythingInRectangle(ppdev, pptl->x, pptl->y, cxThis, cyThis))
return(NULL);
}
// Now see if there is a free rectangle that entirely contains the
// requested rectangle.
for (poh = ppdev->heap.ohFree.pohNext;
poh != &ppdev->heap.ohFree;
poh = poh->pohNext)
{
ASSERTDD(poh->ohState == OH_FREE, "Non-free node in free list");
// See if the current free rectangle completely contains the
// requested rectangle:
if ((poh->x <= pptl->x) &&
(poh->y <= pptl->y) &&
(poh->x + poh->cx >= pptl->x + cxThis) &&
(poh->y + poh->cy >= pptl->y + cyThis))
{
// We can't reserve this rectangle, or make it permanent, if it's
// already been reserved:
if ((!poh->cxReserved) ||
((floh & (FLOH_RESERVE | FLOH_MAKE_PERMANENT)) == 0))
{
// The 'poh' rectangle entirely contains the requested
// rectangle. We may have a situation like this, where
// the smaller rectangle is the requested rectangle, and
// the larger rectangle is the available rectangle:
//
// +-------------------+
// | |
// | +---------+ |
// | |Requested| |
// | | | |
// | +---------+ |
// | |
// +-------------------+
//
// We want to make the space to the left and to the top of
// the requested rectangle available to the heap. Our
// free-space routine only knows how to free space to the
// right and bottom of an allocation, though. So we will
// temporarily allocate temporary rectangles to subdivide
// our rectangle like the following:
//
// +-------------------+
// |Top |
// +----+--------------+
// |Left|Free |
// | | |
// | | |
// | | |
// +----+--------------+
//
// Then, in the resulting 'Free' space, we will allocate the
// upper-left corner for our requested rectangle, after which
// we will go back and free the 'Top' and 'Left' temporary
// rectangles.
pohTop = NULL;
pohLeft = NULL;
cxLeft = pptl->x - poh->x;
cyTop = pptl->y - poh->y;
if (cyTop > 0)
{
if (!bFreeRightAndBottomSpace(ppdev, poh, poh->cx, cyTop,
TRUE))
{
return(NULL);
}
pohTop = poh;
poh = pohTop->pohDown;
}
if (cxLeft > 0)
{
if (!bFreeRightAndBottomSpace(ppdev, poh, cxLeft, poh->cy,
TRUE))
{
pohFree(ppdev, pohTop);
return(NULL);
}
pohLeft = poh;
poh = pohLeft->pohRight;
}
ASSERTDD((poh->x == pptl->x) &&
(poh->y == pptl->y) &&
(poh->x + poh->cx >= poh->x + cxThis) &&
(poh->y + poh->cy >= poh->y + cyThis),
"poh must properly fit requested rectangle");
// Finally, we can subdivide to get our requested rectangle:
if (!bFreeRightAndBottomSpace(ppdev, poh, cxThis, cyThis, FALSE))
poh = NULL; // Fail this call
// Free our temporary rectangles, if there are any:
pohFree(ppdev, pohTop);
pohFree(ppdev, pohLeft);
return(poh);
}
}
}
// There was no free rectangle that completely contains the requested
// rectangle:
return(NULL);
}
/******************************Public*Routine******************************\
* OH* pohMakeRoomAnywhere
*
* Allocates space for an off-screen rectangle. It will attempt to find
* the smallest available free rectangle, and will allocate the block out
* of its upper-left corner. The remaining two rectangles will be placed
* on the available free space list.
*
* If the rectangle would have been large enough to fit into off-screen
* memory, but there is not enough available free space, we will boot
* bitmaps out of off-screen and into DIBs until there is enough room.
*
\**************************************************************************/
OH* pohMakeRoomAnywhere(
PDEV* ppdev,
LONG cxThis, // Width of rectangle to be allocated
LONG cyThis, // Height of rectangle to be allocated
FLONG floh) // May have FLOH_ONLY_IF_ROOM set
{
ULONG cxcyThis; // Width and height search key
OH* pohThis; // Points to found available rectangle we'll use
ASSERTDD((cxThis > 0) && (cyThis > 0), "Illegal allocation size");
// Increase the width to get the proper alignment (thus ensuring that all
// allocations will be properly aligned):
cxThis = (cxThis + (HEAP_X_ALIGNMENT - 1)) & ~(HEAP_X_ALIGNMENT - 1);
// We can't succeed if the requested rectangle is larger than the
// largest possible available rectangle:
if ((cxThis > ppdev->heap.cxMax) || (cyThis > ppdev->heap.cyMax))
return(NULL);
// Find the first available rectangle the same size or larger than
// the requested one:
cxcyThis = CXCY(cxThis, cyThis);
pohThis = ppdev->heap.ohFree.pohNext;
while (pohThis->cxcy < cxcyThis)
{
ASSERTDD(pohThis->ohState == OH_FREE, "Non-free node in free list");
pohThis = pohThis->pohNext;
}
while (pohThis->cy < cyThis)
{
ASSERTDD(pohThis->ohState == OH_FREE, "Non-free node in free list");
pohThis = pohThis->pohNext;
}
ASSERTDD(pohThis->ohState == OH_FREE, "Non-free node in free list");
if (pohThis->cxcy == CXCY_SENTINEL)
{
// There was no space large enough...
if (floh & FLOH_ONLY_IF_ROOM)
return(NULL);
DISPDBG((2, "> Making room for %li x %li allocation...", cxThis, cyThis));
// We couldn't find an available rectangle that was big enough
// to fit our request. So throw things out of the heap until we
// have room, oldest allocations first:
do {
pohThis = ppdev->heap.ohDiscardable.pohPrev; // Least-recently created
ASSERTDD(pohThis != &ppdev->heap.ohDiscardable,
"Ran out of discardable entries -- Max not set correctly");
ASSERTDD(pohThis->ohState == OH_DISCARDABLE,
"Non-discardable node in discardable list");
// We can safely exit here if we have to:
pohThis = pohMoveOffscreenDfbToDib(ppdev, pohThis);
if (pohThis == NULL)
return(NULL);
} while ((pohThis->cx < cxThis) || (pohThis->cy < cyThis));
}
if ((pohThis->cxReserved) && (floh & (FLOH_RESERVE | FLOH_MAKE_PERMANENT)))
{
// We can't reserve this rectangle, or make it permanent, if it's
// already been reserved. So throw absolutely everything out and
// search the free list.
//
// NOTE: This is extremely painful! A better approach would be to
// keep separate 'cxMax' and 'cyMax' variables kept for free
// rectangles that are not reserved (cxMax and cyMax
// currently include reserved free rectangles).
if (!bDiscardEverythingInRectangle(ppdev, 0, 0,
ppdev->cxMemory, ppdev->cyMemory))
{
return(NULL);
}
pohThis = &ppdev->heap.ohFree;
do {
pohThis = pohThis->pohNext;
if (pohThis == &ppdev->heap.ohFree)
return(NULL);
} while ((pohThis->cxReserved) ||
(pohThis->cx < cxThis) ||
(pohThis->cy < cyThis));
}
if (!bFreeRightAndBottomSpace(ppdev, pohThis, cxThis, cyThis, FALSE))
return(NULL);
return(pohThis);
}
/******************************Public*Routine******************************\
* OH* pohAllocate
*
* Allocates a rectangle in off-screen memory.
*
* Types:
*
* FLOH_RESERVE
*
* Reserves an off-screen rectangle. The space may still be used by
* discardable bitmaps until the rectangle is committed via 'bOhCommit'.
*
* FLOH_MAKE_PERMANENT
*
* Allocates an off-screen rectangle that can never be booted
* of the heap. It's the caller's responsibility to manage
* the rectangle, which includes what to do with the memory in
* DrvAssertMode when the display is changed to full-screen
* mode.
*
* Default
*
* Allocates a 'discardable' off-screen rectangle for a DFB that may
* be kicked out of off-screen if the space is needed.
*
* Options:
*
* FLOH_ONLY_IF_ROOM
*
* Allocates an off-screen rectangle only if there is free space
* available -- i.e., no discardable rectangles will be moved out of
* off-screen to make room.
*
* Default
*
* May move discardable rectangles out of off-screen to make room.
*
* Arguments:
*
* pptl
*
* If NULL, the rectangle will be allocated anywhere in un-used offscreen
* memory.
*
* If non-NULL, is a requested position for the rectangle.
*
* NOTE: The heap will quickly fragment if arbitrary positions are
* requested. This position option works best if there is only
* one specific rectangle ever requested, or if the allocations
* are always wider than they are high.
*
\**************************************************************************/
OH* pohAllocate(
PDEV* ppdev,
POINTL* pptl, // Optional requested position of rectangle
LONG cxThis, // Width of rectangle to be allocated
LONG cyThis, // Height of rectangle to be allocated
FLOH floh) // Allocation flags
{
OH* pohThis; // Points to found available rectangle we'll use
OH* pohRoot; // Point to root of list where we'll insert node
ULONG cxcy;
OH* pohNext;
OH* pohPrev;
ASSERTDD((floh & (FLOH_RESERVE | FLOH_MAKE_PERMANENT))
!= (FLOH_RESERVE | FLOH_MAKE_PERMANENT),
"Illegal flags -- can't set both FLOH_RESERVE and FLOH_MAKE_PERMANENT");
if (pptl == NULL)
{
pohThis = pohMakeRoomAnywhere(ppdev, cxThis, cyThis, floh);
if (pohThis == NULL)
DISPDBG((2, "Can't allocate %li x %li with flags %li",
cxThis, cyThis, floh));
}
else
{
pohThis = pohMakeRoomAtLocation(ppdev, pptl, cxThis, cyThis, floh);
if (pohThis == NULL)
DISPDBG((2, "Can't allocate %li x %li at %li, %li with flags %li",
cxThis, cyThis, pptl->x, pptl->y, floh));
}
if (pohThis == NULL)
return(NULL);
// Calculate the effective start address for this bitmap in off-
// screen memory:
pohThis->pvScan0 = ppdev->pjScreen + (pohThis->y * ppdev->lDelta)
+ (pohThis->x * ppdev->cBpp);
// The caller is responsible for setting this field:
pohThis->pdsurf = NULL;
// Our 'reserve' logic expects the node to have 'free' status:
ASSERTDD(pohThis->ohState == OH_FREE, "Node not free after making room");
ASSERTDD(((floh & (FLOH_RESERVE | FLOH_MAKE_PERMANENT)) == 0) ||
(pohThis->cxReserved == 0),
"Can't reserve a rectangle that's already reserved");
if (floh & FLOH_RESERVE)
{
// A non-zero value for 'cxReserved' means it's reserved:
pohThis->cxReserved = pohThis->cx;
pohThis->cyReserved = pohThis->cy;
// Remove this node from its place in the free list:
pohThis->pohPrev->pohNext = pohThis->pohNext;
pohThis->pohNext->pohPrev = pohThis->pohPrev;
// Now insert the node, in order, back into the free list:
cxcy = pohThis->cxcy;
pohNext = ppdev->heap.ohFree.pohNext;
while (pohNext->cxcy < cxcy)
{
pohNext = pohNext->pohNext;
}
pohPrev = pohNext->pohPrev;
pohPrev->pohNext = pohThis;
pohNext->pohPrev = pohThis;
pohThis->pohPrev = pohPrev;
pohThis->pohNext = pohNext;
}
else
{
// Remove this node from the free list:
pohThis->pohPrev->pohNext = pohThis->pohNext;
pohThis->pohNext->pohPrev = pohThis->pohPrev;
if (floh & FLOH_MAKE_PERMANENT)
{
// Change status of node and insert into permanent list:
pohThis->ohState = OH_PERMANENT;
pohRoot = &ppdev->heap.ohPermanent;
// Calculate the new maximum size rectangle available
// for allocation:
vCalculateMaximumNonPermanent(ppdev);
}
else
{
// Change status of node and insert into discardable list:
pohThis->ohState = OH_DISCARDABLE;
pohRoot = &ppdev->heap.ohDiscardable;
}
// Now insert the node at the head of the appropriate list:
pohThis->pohNext = pohRoot->pohNext;
pohThis->pohPrev = pohRoot;
pohRoot->pohNext->pohPrev = pohThis;
pohRoot->pohNext = pohThis;
}
DISPDBG((2, " Allocated (%li x %li) at (%li, %li) with flags %li",
cxThis, cyThis, pohThis->x, pohThis->y, floh));
return(pohThis);
}
/******************************Public*Routine******************************\
* BOOL bOhCommit
*
* If 'bCommit' is TRUE, converts a 'reserved' allocation to 'permanent,'
* moving from off-screen memory any discardable allocations that may have
* been using the space.
*
* If 'bCommit' is FALSE, converts a 'permanent' allocation to 'reserved,'
* allowing the space to be used by discardable allocations.
*
\**************************************************************************/
BOOL bOhCommit(
PDEV* ppdev,
OH* poh,
BOOL bCommit)
{
BOOL bRet;
LONG cx;
LONG cy;
ULONG cxcy;
OH* pohRoot;
OH* pohNext;
OH* pohPrev;
bRet = FALSE; // Assume failure
if (poh == NULL)
return(bRet);
if ((bCommit) && (poh->cxReserved))
{
if (bDiscardEverythingInRectangle(ppdev, poh->x, poh->y,
poh->cxReserved, poh->cyReserved))
{
DISPDBG((2, "Commited %li x %li at (%li, %li)",
poh->cx, poh->cy, poh->x, poh->y));
poh->ohState = OH_PERMANENT;
// Remove this node from the free list:
poh->pohPrev->pohNext = poh->pohNext;
poh->pohNext->pohPrev = poh->pohPrev;
// Now insert the node at the head of the permanent list:
pohRoot = &ppdev->heap.ohPermanent;
poh->pohNext = pohRoot->pohNext;
poh->pohPrev = pohRoot;
pohRoot->pohNext->pohPrev = poh;
pohRoot->pohNext = poh;
bRet = TRUE;
}
}
else if ((!bCommit) && (poh->ohState == OH_PERMANENT))
{
DISPDBG((2, "Decommited %li x %li at (%li, %li)",
poh->cx, poh->cy, poh->x, poh->y));
poh->ohState = OH_FREE;
poh->cxReserved = poh->cx;
poh->cyReserved = poh->cy;
// Remove this node from the permanent list:
poh->pohPrev->pohNext = poh->pohNext;
poh->pohNext->pohPrev = poh->pohPrev;
// Now insert the node, in order, into the free list:
cxcy = poh->cxcy;
pohNext = ppdev->heap.ohFree.pohNext;
while (pohNext->cxcy < cxcy)
{
pohNext = pohNext->pohNext;
}
pohPrev = pohNext->pohPrev;
pohPrev->pohNext = poh;
pohNext->pohPrev = poh;
poh->pohPrev = pohPrev;
poh->pohNext = pohNext;
bRet = TRUE;
}
// Recalculate the biggest rectangle available for allocation:
vCalculateMaximumNonPermanent(ppdev);
return(bRet);
}
/******************************Public*Routine******************************\
* BOOL bMoveDibToOffscreenDfbIfRoom
*
* Converts the DIB DFB to an off-screen DFB, if there's room for it in
* off-screen memory.
*
* Returns: FALSE if there wasn't room, TRUE if successfully moved.
*
\**************************************************************************/
BOOL bMoveDibToOffscreenDfbIfRoom(
PDEV* ppdev,
DSURF* pdsurf)
{
OH* poh;
SURFOBJ* pso;
RECTL rclDst;
POINTL ptlSrc;
HSURF hsurf;
ASSERTDD(pdsurf->dt == DT_DIB,
"Can't move a bitmap off-screen when it's already off-screen");
// If we're in full-screen mode, we can't move anything to off-screen
// memory:
if (!ppdev->bEnabled)
return(FALSE);
poh = pohAllocate(ppdev, NULL, pdsurf->sizl.cx, pdsurf->sizl.cy,
FLOH_ONLY_IF_ROOM);
if (poh == NULL)
{
// There wasn't any free room.
return(FALSE);
}
// 'pdsurf->sizl' is the actual bitmap dimension, not 'poh->cx' or
// 'poh->cy'.
rclDst.left = poh->x;
rclDst.top = poh->y;
rclDst.right = rclDst.left + pdsurf->sizl.cx;
rclDst.bottom = rclDst.top + pdsurf->sizl.cy;
ptlSrc.x = 0;
ptlSrc.y = 0;
ppdev->pfnPutBits(ppdev, pdsurf->pso, &rclDst, &ptlSrc);
// Update the data structures to reflect the new off-screen node:
pso = pdsurf->pso;
pdsurf->dt = DT_SCREEN;
pdsurf->poh = poh;
poh->pdsurf = pdsurf;
// Now free the DIB. Get the hsurf from the SURFOBJ before we unlock
// it (it's not legal to dereference psoDib when it's unlocked):
hsurf = pso->hsurf;
EngUnlockSurface(pso);
EngDeleteSurface(hsurf);
return(TRUE);
}
/******************************Public*Routine******************************\
* OH* pohMoveOffscreenDfbToDib
*
* Converts the DFB from being off-screen to being a DIB.
*
* Note: The caller does NOT have to call 'pohFree' on 'poh' after making
* this call.
*
* Returns: NULL if the function failed (due to a memory allocation).
* Otherwise, it returns a pointer to the coalesced off-screen heap
* node that has been made available for subsequent allocations
* (useful when trying to free enough memory to make a new
* allocation).
\**************************************************************************/
OH* pohMoveOffscreenDfbToDib(
PDEV* ppdev,
OH* poh)
{
DSURF* pdsurf;
HBITMAP hbmDib;
SURFOBJ* pso;
RECTL rclDst;
POINTL ptlSrc;
DISPDBG((2, "Throwing out %li x %li at (%li, %li)!",
poh->cx, poh->cy, poh->x, poh->y));
pdsurf = poh->pdsurf;
ASSERTDD((poh->x != 0) || (poh->y != 0),
"Can't make the visible screen into a DIB");
ASSERTDD(pdsurf->dt != DT_DIB,
"Can't make a DIB into even more of a DIB");
hbmDib = EngCreateBitmap(pdsurf->sizl, 0, ppdev->iBitmapFormat,
BMF_TOPDOWN, NULL);
if (hbmDib)
{
if (EngAssociateSurface((HSURF) hbmDib, ppdev->hdevEng, 0))
{
pso = EngLockSurface((HSURF) hbmDib);
if (pso != NULL)
{
rclDst.left = 0;
rclDst.top = 0;
rclDst.right = pdsurf->sizl.cx;
rclDst.bottom = pdsurf->sizl.cy;
ptlSrc.x = poh->x;
ptlSrc.y = poh->y;
ppdev->pfnGetBits(ppdev, pso, &rclDst, &ptlSrc);
pdsurf->dt = DT_DIB;
pdsurf->pso = pso;
// Don't even bother checking to see if this DIB should
// be put back into off-screen memory until the next
// heap 'free' occurs:
pdsurf->iUniq = ppdev->iHeapUniq;
pdsurf->cBlt = 0;
// Remove this node from the off-screen DFB list, and free
// it. 'pohFree' will never return NULL:
return(pohFree(ppdev, poh));
}
}
// Fail case:
EngDeleteSurface((HSURF) hbmDib);
}
return(NULL);
}
/******************************Public*Routine******************************\
* BOOL bMoveEverythingFromOffscreenToDibs
*
* This function is used when we're about to enter full-screen mode, which
* would wipe all our off-screen bitmaps. GDI can ask us to draw on
* device bitmaps even when we're in full-screen mode, and we do NOT have
* the option of stalling the call until we switch out of full-screen.
* We have no choice but to move all the off-screen DFBs to DIBs.
*
* Returns TRUE if all DSURFs have been successfully moved.
*
\**************************************************************************/
BOOL bMoveAllDfbsFromOffscreenToDibs(
PDEV* ppdev)
{
// Throw out any discardable bitmaps over the entire surface:
return(bDiscardEverythingInRectangle(ppdev, 0, 0,
ppdev->cxMemory, ppdev->cyMemory));
}
/******************************Public*Routine******************************\
* HBITMAP DrvCreateDeviceBitmap
*
* Function called by GDI to create a device-format-bitmap (DFB). We will
* always try to allocate the bitmap in off-screen; if we can't, we simply
* fail the call and GDI will create and manage the bitmap itself.
*
* Note: We do not have to zero the bitmap bits. GDI will automatically
* call us via DrvBitBlt to zero the bits (which is a security
* consideration).
*
\**************************************************************************/
HBITMAP DrvCreateDeviceBitmap(
DHPDEV dhpdev,
SIZEL sizl,
ULONG iFormat)
{
PDEV* ppdev;
OH* poh;
DSURF* pdsurf;
HBITMAP hbmDevice;
FLONG flHooks;
ppdev = (PDEV*) dhpdev;
// If we're in full-screen mode, we hardly have any off-screen memory
// in which to allocate a DFB. LATER: We could still allocate an
// OH node and put the bitmap on the DIB DFB list for later promotion.
if (!ppdev->bEnabled)
return(0);
// We only support device bitmaps that are the same colour depth
// as our display.
//
// Actually, those are the only kind GDI will ever call us with,
// but we may as well check. Note that this implies you'll never
// get a crack at 1bpp bitmaps.
if (iFormat != ppdev->iBitmapFormat)
return(0);
// We don't want anything 8x8 or smaller -- they're typically brush
// patterns which we don't particularly want to stash in off-screen
// memory:
if ((sizl.cx <= 8) && (sizl.cy <= 8))
return(0);
poh = pohAllocate(ppdev, NULL, sizl.cx, sizl.cy, 0);
if (poh != NULL)
{
pdsurf = EngAllocMem(0, sizeof(DSURF), ALLOC_TAG);
if (pdsurf != NULL)
{
hbmDevice = EngCreateDeviceBitmap((DHSURF) pdsurf, sizl, iFormat);
if (hbmDevice != NULL)
{
flHooks = ppdev->flHooks;
// Setting the SYNCHRONIZEACCESS flag tells GDI that we
// want all drawing to the bitmaps to be synchronized (GDI
// is multi-threaded and by default does not synchronize
// device bitmap drawing -- it would be a Bad Thing for us
// to have multiple threads using the accelerator at the
// same time):
flHooks |= HOOK_SYNCHRONIZEACCESS;
// It's a device-managed surface; make sure we don't set
// HOOK_SYNCHRONIZE, otherwise we may confuse GDI:
flHooks &= ~HOOK_SYNCHRONIZE;
if (EngAssociateSurface((HSURF) hbmDevice, ppdev->hdevEng,
flHooks))
{
pdsurf->dt = DT_SCREEN;
pdsurf->poh = poh;
pdsurf->sizl = sizl;
pdsurf->ppdev = ppdev;
poh->pdsurf = pdsurf;
return(hbmDevice);
}
EngDeleteSurface((HSURF) hbmDevice);
}
EngFreeMem(pdsurf);
}
pohFree(ppdev, poh);
}
return(0);
}
/******************************Public*Routine******************************\
* VOID DrvDeleteDeviceBitmap
*
* Deletes a DFB.
*
\**************************************************************************/
VOID DrvDeleteDeviceBitmap(
DHSURF dhsurf)
{
DSURF* pdsurf;
PDEV* ppdev;
SURFOBJ* psoDib;
HSURF hsurfDib;
pdsurf = (DSURF*) dhsurf;
ppdev = pdsurf->ppdev;
if (pdsurf->dt == DT_SCREEN)
{
pohFree(ppdev, pdsurf->poh);
}
else
{
ASSERTDD(pdsurf->dt == DT_DIB, "Expected DIB type");
psoDib = pdsurf->pso;
// Get the hsurf from the SURFOBJ before we unlock it (it's not
// legal to dereference psoDib when it's unlocked):
hsurfDib = psoDib->hsurf;
EngUnlockSurface(psoDib);
EngDeleteSurface(hsurfDib);
}
EngFreeMem(pdsurf);
}
/******************************Public*Routine******************************\
* BOOL bAssertModeOffscreenHeap
*
* This function is called whenever we switch in or out of full-screen
* mode. We have to convert all the off-screen bitmaps to DIBs when
* we switch to full-screen (because we may be asked to draw on them even
* when in full-screen, and the mode switch would probably nuke the video
* memory contents anyway).
*
\**************************************************************************/
BOOL bAssertModeOffscreenHeap(
PDEV* ppdev,
BOOL bEnable)
{
BOOL b = TRUE;
if (!bEnable)
{
b = bMoveAllDfbsFromOffscreenToDibs(ppdev);
}
return(b);
}
/******************************Public*Routine******************************\
* VOID vDisableOffscreenHeap
*
* Frees any resources allocated by the off-screen heap.
*
\**************************************************************************/
VOID vDisableOffscreenHeap(
PDEV* ppdev)
{
OHALLOC* poha;
OHALLOC* pohaNext;
SURFOBJ* psoPunt;
HSURF hsurf;
psoPunt = ppdev->psoPunt;
if (psoPunt != NULL)
{
hsurf = psoPunt->hsurf;
EngUnlockSurface(psoPunt);
EngDeleteSurface(hsurf);
}
psoPunt = ppdev->psoPunt2;
if (psoPunt != NULL)
{
hsurf = psoPunt->hsurf;
EngUnlockSurface(psoPunt);
EngDeleteSurface(hsurf);
}
poha = ppdev->heap.pohaChain;
while (poha != NULL)
{
pohaNext = poha->pohaNext; // Grab the next pointer before it's freed
EngFreeMem(poha);
poha = pohaNext;
}
}
/******************************Public*Routine******************************\
* BOOL bEnableOffscreenHeap
*
* Initializes the off-screen heap using all available video memory,
* accounting for the portion taken by the visible screen.
*
* Input: ppdev->cxScreen
* ppdev->cyScreen
* ppdev->cxMemory
* ppdev->cyMemory
*
\**************************************************************************/
BOOL bEnableOffscreenHeap(
PDEV* ppdev)
{
OH* poh;
SIZEL sizl;
HSURF hsurf;
POINTL ptlScreen;
DISPDBG((1, "Screen: %li x %li Memory: %li x %li",
ppdev->cxScreen, ppdev->cyScreen, ppdev->cxMemory, ppdev->cyMemory));
ASSERTDD((ppdev->cxScreen <= ppdev->cxMemory) &&
(ppdev->cyScreen <= ppdev->cyMemory),
"Memory must not have smaller dimensions than visible screen!");
ppdev->heap.pohaChain = NULL;
ppdev->heap.pohFreeList = NULL;
// Initialize the available list, which will be a circular
// doubly-linked list kept in ascending 'cxcy' order, with a
// 'sentinel' at the end of the list:
poh = pohNewNode(ppdev);
if (poh == NULL)
goto ReturnFalse;
// The first node describes the entire video memory size:
poh->pohNext = &ppdev->heap.ohFree;
poh->pohPrev = &ppdev->heap.ohFree;
poh->ohState = OH_FREE;
poh->x = 0;
poh->y = 0;
poh->xy = 0;
poh->cx = ppdev->cxMemory;
poh->cy = ppdev->cyMemory;
poh->cxcy = CXCY(ppdev->cxMemory, ppdev->cyMemory);
poh->pohLeft = &ppdev->heap.ohFree;
poh->pohUp = &ppdev->heap.ohFree;
poh->pohRight = &ppdev->heap.ohFree;
poh->pohDown = &ppdev->heap.ohFree;
poh->pvScan0 = ppdev->pjScreen;
// The second node is our free list sentinel:
ppdev->heap.ohFree.pohNext = poh;
ppdev->heap.ohFree.pohPrev = poh;
ppdev->heap.ohFree.cxcy = CXCY_SENTINEL;
ppdev->heap.ohFree.cx = 0x7fffffff;
ppdev->heap.ohFree.cy = 0x7fffffff;
ppdev->heap.ohFree.ohState = OH_FREE;
// Initialize the discardable list, which will be a circular
// doubly-linked list kept in order, with a sentinel at the end.
// This node is also used for the screen-surface, for its offset:
ppdev->heap.ohDiscardable.pohNext = &ppdev->heap.ohDiscardable;
ppdev->heap.ohDiscardable.pohPrev = &ppdev->heap.ohDiscardable;
ppdev->heap.ohDiscardable.ohState = OH_DISCARDABLE;
// Initialize the permanent list, which will be a circular
// doubly-linked list kept in order, with a sentinel at the end.
ppdev->heap.ohPermanent.pohNext = &ppdev->heap.ohPermanent;
ppdev->heap.ohPermanent.pohPrev = &ppdev->heap.ohPermanent;
ppdev->heap.ohPermanent.ohState = OH_PERMANENT;
// For the moment, make the max really big so that the first
// allocation we're about to do will succeed:
ppdev->heap.cxMax = 0x7fffffff;
ppdev->heap.cyMax = 0x7fffffff;
ptlScreen.x = 0;
ptlScreen.y = 0;
// Finally, reserve the upper-left corner for the screen. We can
// actually throw away 'poh' because we'll never need it again
// (not even for disabling the off-screen heap since everything is
// freed using OHALLOCs):
poh = pohAllocate(ppdev, &ptlScreen, ppdev->cxScreen, ppdev->cyScreen,
FLOH_MAKE_PERMANENT);
ASSERTDD((poh != NULL) && (poh->x == 0) && (poh->y == 0) &&
(poh->cx >= ppdev->cxScreen) && (poh->cy >= ppdev->cyScreen),
"Screen allocation messed up");
// Remember it so that we can associate the screen SURFOBJ with this
// poh:
ppdev->pohScreen = poh;
// Here we allocate space for the ET6000 to use as a blt buffer. This
// lets us perform rops on host bitmaps by transferring them a line at
// a time into offscreen memory. We allocate screen_width * 2 lines
// so we can double buffer the transfers.
//
if (ppdev->ulChipID == ET6000)
{
OH* pohTemp;
ppdev->lBltBufferPitch = ppdev->lDelta;
// We need to fudge the ppdev->heap.cxMax value so that it doesn't
// forbid the next allocation.
ppdev->heap.cxMax = 0x7fffffff;
ppdev->heap.cyMax = 0x7fffffff;
pohTemp = pohAllocate(ppdev, NULL, ppdev->cxScreen, 2, FLOH_MAKE_PERMANENT);
if (pohTemp == NULL)
{
DISPDBG((0, "Could not allocate space for ET6000 blt buffer"));
goto ReturnFalse;
}
DISPDBG((1, "ET6000 blt buffer allocated successfully (%p)", pohTemp));
DISPDBG((1, " poh->x = %ld", pohTemp->x));
DISPDBG((1, " poh->y = %ld", pohTemp->y));
DISPDBG((1, " poh->cx = %ld", pohTemp->cx));
DISPDBG((1, " poh->cy = %ld", pohTemp->cy));
ppdev->pohBltBuffer = pohTemp;
}
// Allocate a 'punt' SURFOBJ we'll use when the device-bitmap is in
// off-screen memory, but we want GDI to draw to it directly as an
// engine-managed surface:
sizl.cx = ppdev->cxMemory;
sizl.cy = ppdev->cyMemory;
// We want to create it with exactly the same hooks and capabilities
// as our primary surface. We will override the 'lDelta' and 'pvScan0'
// fields later:
hsurf = (HSURF) EngCreateBitmap(sizl,
0xbadf00d,
ppdev->iBitmapFormat,
BMF_TOPDOWN,
(VOID*) 0xbadf00d);
if ((hsurf == 0) ||
(!EngAssociateSurface(hsurf, ppdev->hdevEng, ppdev->flHooks)) ||
(!(ppdev->psoPunt = EngLockSurface(hsurf))))
{
DISPDBG((0, "Failed punt surface creation"));
EngDeleteSurface(hsurf);
goto ReturnFalse;
}
// We need another for doing DrvBitBlt and DrvCopyBits when both
// surfaces are off-screen bitmaps:
hsurf = (HSURF) EngCreateBitmap(sizl,
0xbadf00d,
ppdev->iBitmapFormat,
BMF_TOPDOWN,
(VOID*) 0xbadf00d);
if ((hsurf == 0) ||
(!EngAssociateSurface(hsurf, ppdev->hdevEng, ppdev->flHooks)) ||
(!(ppdev->psoPunt2 = EngLockSurface(hsurf))))
{
DISPDBG((0, "Failed punt surface creation"));
EngDeleteSurface(hsurf);
goto ReturnFalse;
}
DISPDBG((5, "Passed bEnableOffscreenHeap"));
if (poh != NULL)
return(TRUE);
ReturnFalse:
DISPDBG((0, "Failed bEnableOffscreenHeap"));
return(FALSE);
}