2025-04-27 07:49:33 -04:00

725 lines
26 KiB
C

/******************************Module*Header*******************************\
* Module Name: savescr.c *
* *
* DrvSaveScreenBits *
* *
* Copyright (c) 1992-1995 Microsoft Corporation *
\**************************************************************************/
#include <driver.h>
// This is just a unique ID that the driver will recongize. Hopefully,
// nothing will ever call with this ID by pure chance. We need something that
// can't possibly be a result of one of the Allocs done by the driver for
// the saves to system memory, and it can't be 0 (which indicates failure).
#define SAVED_OFFSCREEN_ID ((ULONG)-1)
ULONG
ulSaveOrRestoreBits(
SURFOBJ *,
PPDEV,
RECTL *,
BOOL);
VOID
vRestoreScreenBitsFromMemory(
PDEVSURF pdsurf,
PRECTL prcl,
PBYTE pjSrcBuffer,
ULONG ulRestoreWidthInBytes,
ULONG ulSrcDelta
);
VOID
vSaveScreenBitsToMemory(
PDEVSURF pdsurf,
PRECTL prcl,
PVOID pjDestBuffer,
ULONG ulSaveWidthInBytes,
ULONG ulSaveHeight,
ULONG ulDestScanWidth
);
/******************************Public*Routine******************************\
* DrvSaveScreenBits(pso,iMode,iIdent,prcl) *
* *
* Saves and restores the specified area of the screen *
* *
\**************************************************************************/
ULONG DrvSaveScreenBits(SURFOBJ *pso, ULONG iMode, ULONG iIdent, RECTL *prcl)
{
PDEVSURF pdsurf;
PPDEV ppdev;
PSAVED_SCREEN_BITS pSSB, *pLastSSBPtr, pSSBTemp;
BOOL bIdentFound;
ULONG ulSaveSize, ulSaveHeight;
ULONG ulSaveWidthInBytes, ulSaveWidthInAlignedBytes;
ULONG ulRet;
pdsurf = (PDEVSURF) pso->dhsurf;
ppdev = pdsurf->ppdev; // find the PDEV that goes with this surface
//
// Save, restore, or free a block of screen bits.
//
switch(iMode)
{
//
// Save a block of screen bits.
//
case SS_SAVE:
if ((ppdev->fl & DRIVER_OFFSCREEN_REFRESHED) && !ppdev->bBitsSaved)
{
//
// Save bits to offscreen memory.
//
ulRet = ulSaveOrRestoreBits(pso, ppdev, prcl, TRUE);
if (ulRet)
{
ppdev->bBitsSaved = TRUE;
return(ulRet);
}
//
// If you get to here, save to offscreen failed. Maybe the
// region was too large. Anyway, fall through to the code
// which saves to system memory.
//
}
//
// For one reason or another, the offscreen memory cannot be used.
//
// Figure out how big the save area will be
ulSaveHeight = prcl->bottom - prcl->top;
ulSaveWidthInBytes =
((ULONG)((prcl->right + 7) - (prcl->left & ~0x07))) >> 3;
// Not enough offscreen memory; store in system memory.
// Calculate new buffer width, allowing for padding so we can
// dword align
ulSaveWidthInAlignedBytes =
(((ULONG)((prcl->right + 31) - (prcl->left & ~0x1F)))
>> 5) << 2;
// # of bytes to hold all 4 planes of save rect in memory
ulSaveSize = ((ulSaveHeight * ulSaveWidthInAlignedBytes) << 2)
+ sizeof(SAVED_SCREEN_BITS);
// If the preallocated saved screen bits buffer is free and big
// enough to handle this save, we'll use that
if ((ppdev->flPreallocSSBBufferInUse == FALSE) &&
(ulSaveSize <= ppdev->ulPreallocSSBSize))
{
// Save in preallocated buffer
pSSB = (PSAVED_SCREEN_BITS) ppdev->pjPreallocSSBBuffer;
// Mark that we're saving in the preallocated buffer
pSSB->bFlags = SSB_IN_PREALLOC_BUFFER;
// Make sure no other screen bits save tries to use the
// buffer
ppdev->flPreallocSSBBufferInUse = TRUE;
}
else
{
// Save in system memory buffer
// Allocate a structure to contain the save info and the
// save buffer (four planes' worth)
//
pSSB = (PSAVED_SCREEN_BITS) EngAllocMem(0, ulSaveSize, ALLOC_TAG);
if (pSSB == NULL)
{
// Couldn't get memory, so fail this call
return((ULONG)0);
}
// Mark that we're not saving in display memory
pSSB->bFlags = 0;
}
// Start address at which to save, accounting for
// the number of bytes by which to pad on the left to dword
// align (assumes each scan line starts dword aligned, which is
// true in 640, 800, and 1024 wide cases)
pSSB->pjBuffer = ((PBYTE) pSSB) + sizeof(SAVED_SCREEN_BITS) +
((prcl->left >> 3) & 0x03);
pSSB->ulSaveWidthInBytes = ulSaveWidthInBytes;
// Distance from end of one scan to start of next (number of
// padding bytes for dword alignment purposes)
pSSB->ulDelta =
ulSaveWidthInAlignedBytes - pSSB->ulSaveWidthInBytes;
// Save the rectangle to system memory
vSaveScreenBitsToMemory(pdsurf,
prcl,
pSSB->pjBuffer,
pSSB->ulSaveWidthInBytes,
ulSaveHeight,
ulSaveWidthInAlignedBytes);
// Link the new saved screen bits block into the list
pSSB->pvNextSSB = pdsurf->ssbList;
pdsurf->ssbList = pSSB;
return((ULONG) pSSB);
//
// Restore a saved screen bits block to the screen, then free it.
//
case SS_RESTORE:
if (iIdent == SAVED_OFFSCREEN_ID)
{
if (!ppdev->bBitsSaved)
{
//
// We must have blown the offscreen cache
//
return(FALSE);
}
ppdev->bBitsSaved = FALSE; // successful or not, destroy the bits
if (!ulSaveOrRestoreBits(pso, ppdev, prcl, FALSE))
{
RIP("DrvSaveScreenBits (restore): restore failed\n");
}
return(TRUE);
}
// Point to the first block in the saved screen bits list
pSSB = pdsurf->ssbList;
// Try to find the specified saved screen bits block
bIdentFound = FALSE;
while ((pSSB != (PSAVED_SCREEN_BITS) NULL) && !bIdentFound)
{
if (pSSB == (PSAVED_SCREEN_BITS) iIdent)
{
// Handle copies from offscreen memory and system memory
// separately
vRestoreScreenBitsFromMemory(pdsurf,
prcl,
pSSB->pjBuffer,
pSSB->ulSaveWidthInBytes,
pSSB->ulDelta);
bIdentFound = TRUE;
}
else
{
// Not a match, so check another block, if there is one.
// Point to the next saved screen bits block
pSSB = (PSAVED_SCREEN_BITS) pSSB->pvNextSSB;
}
}
// See if we succeeded in finding a block to restore
if (!bIdentFound)
{
// It was a bad identifier, so we'll return failure
DISPDBG((0, "DrvSaveScreenBits SS_RESTORE invalid iIdent"));
return(FALSE);
}
// Always free the saved screen bits block after restoring it
//
// Free up the saved screen bits block.
//
case SS_FREE:
if (iIdent == SAVED_OFFSCREEN_ID)
{
ppdev->bBitsSaved = FALSE;
return(TRUE);
}
// Point to the first block in the saved screen bits list
pSSB = pdsurf->ssbList;
// Point to the pointer to the first block, so we can unlink the
// first block if it's the one we're freeing
pLastSSBPtr = &pdsurf->ssbList;
// Try to find the specified saved screen bits block
while (pSSB != (PSAVED_SCREEN_BITS) NULL)
{
if (pSSB == (PSAVED_SCREEN_BITS) iIdent)
{
// It's a match; free up this block
// Unlink the block from the list
*pLastSSBPtr = (PSAVED_SCREEN_BITS) pSSB->pvNextSSB;
if (pSSB->bFlags & SSB_IN_PREALLOC_BUFFER)
{
// If the block's save area is in the preallocated
// buffer, mark that the buffer is no longer in use
// and is free for reuse
ppdev->flPreallocSSBBufferInUse = FALSE;
// We're done; there's nothing to free up
return(TRUE);
}
// Deallocate the block's memory
EngFreeMem(pSSB);
// We've successfully freed the block
return(TRUE);
}
// Not a match, so check another block, if there is one
// Remember the block that points to the block we're advancing
// to, for unlinking later
pLastSSBPtr = (PSAVED_SCREEN_BITS *) &pSSB->pvNextSSB;
// Point to the next saved screen bits block
pSSB = (PSAVED_SCREEN_BITS) pSSB->pvNextSSB;
}
// It was a bad identifier, so we'll do nothing. We won't return
// FALSE because SS_FREE always returns TRUE
DISPDBG((0, "DrvSaveScreenBits SS_FREE invalid iIdent"));
return(TRUE);
//
// An unknown mode was passed in.
//
default:
DISPDBG((0, "DrvSaveScreenBits invalid iMode"));
return(FALSE);
break;
}
}
/******************************Public*Routine******************************\
* vCopyRects(pso,ppdev,prclSrc,prclTrg,cxPad,bIsSave) *
* *
* Breaks prclSrc up and copies the parts into prclTrg *
* *
\**************************************************************************/
VOID vCopyRects(SURFOBJ *pso, PPDEV ppdev, RECTL * prclSrc, RECTL * prclTrg,
LONG cxPad, BOOL bIsSave)
{
RECTL rclOnScreen;
RECTL rclOffScreen;
POINTL * pptlSrcTmp;
RECTL * prclTrgTmp;
ULONG cx, cy;
ULONG cAlign;
// We are assuming here that either the Trg is wider than the Src, or
// the Trg is taller than the src.
// We are assuming that if there is a nonzero cxPad, we are copying to
// a rectangle such that the src is taller than the dst.
// In other words, the prclTrg is a rectangle in the bottom offscreen
// memory region, and the prclSrc needs to be broken up.
ASSERT(cxPad == 0 ||
(prclSrc->bottom - prclSrc->top > prclTrg->bottom - prclTrg->top),
"DrvSaveScreenBits: vCopyRects - cxPad is invalid\n");
// Make sure that the src and trg are dword aligned.
cAlign = (((prclSrc->left) - (prclTrg->left)) & (PLANAR_PELS_PER_CPU_ADDRESS - 1));
if ((prclSrc->right - prclSrc->left) > prclTrg->right - prclTrg->left)
{
if ((prclSrc->bottom - prclSrc->top) >= prclTrg->bottom - prclTrg->top)
{
RIP("DrvSaveScreenBits: vCopyRects src is bigger than trg\n");
}
//
// we need to break it up into vertical strips
//
cx = prclTrg->right - prclTrg->left;
cy = prclSrc->bottom - prclSrc->top;
ASSERT(cx != 0, "DrvSaveScreenBits: vCopyRects (v save width == 0)\n");
ASSERT(cy != 0, "DrvSaveScreenBits: vCopyRects (v save height == 0)\n");
rclOnScreen.right = prclSrc->left;
rclOnScreen.top = prclSrc->top;
rclOnScreen.bottom = prclSrc->top + cy;
rclOffScreen.left = prclTrg->left;
rclOffScreen.bottom = prclTrg->top;
// align offscreen rect to src
rclOffScreen.left += cAlign;
/* variable used before being initialized */
// rclOffScreen.right += cAlign;
while (rclOnScreen.right < prclSrc->right)
{
cx = min(cx,(ULONG)(prclSrc->right - rclOnScreen.right));
ASSERT(cx != 0, "DrvSaveScreenBits: vCopyRects (cx == 0)\n");
rclOnScreen.left = rclOnScreen.right;
rclOnScreen.right += cx;
rclOffScreen.right = rclOffScreen.left + cx; // in case cx is thinner
// on last strip
rclOffScreen.top = rclOffScreen.bottom;
rclOffScreen.bottom += cy;
if (rclOffScreen.bottom > prclTrg->bottom)
{
RIP("DrvSaveScreenBits: "
"vCopyRects can't fit src into trg (vertical)\n");
}
if (bIsSave)
{
// save
pptlSrcTmp = (POINTL *) &rclOnScreen;
prclTrgTmp = &rclOffScreen;
DISPDBG((1,"DrvSaveScreenBits (v save): "));
}
else
{
// restore
pptlSrcTmp = (POINTL *) &rclOffScreen;
prclTrgTmp = &rclOnScreen;
DISPDBG((1,"DrvSaveScreenBits (v restore): "));
}
DISPDBG((1,"%08x,%08x,%08x,%08x %lux%lu\n",
rclOffScreen.left,
rclOffScreen.top,
rclOffScreen.right,
rclOffScreen.bottom,
rclOffScreen.right - rclOffScreen.left,
rclOffScreen.bottom - rclOffScreen.top
));
ASSERT(((prclTrgTmp->left ^ pptlSrcTmp->x) &
(PLANAR_PELS_PER_CPU_ADDRESS - 1)) == 0,
"DrvSaveScreenBits (v): Src and Target are not aligned\n");
DrvCopyBits(pso, // psoDst (screen)
pso, // psoSrc (screen)
NULL, // pco (none)
NULL, // pxlo (none)
prclTrgTmp, // prclDst
pptlSrcTmp); // pptlSrc
}
}
else if ((prclSrc->bottom - prclSrc->top) > prclTrg->bottom - prclTrg->top)
{
//
// we need to break it up into horizontal strips
//
cx = prclSrc->right - prclSrc->left;
cy = prclTrg->bottom - prclTrg->top;
ASSERT(cx != 0, "DrvSaveScreenBits: vCopyRects (h save width == 0)\n");
ASSERT(cy != 0, "DrvSaveScreenBits: vCopyRects (h save height == 0)\n");
rclOnScreen.bottom = prclSrc->top;
rclOnScreen.left = prclSrc->left;
rclOnScreen.right = prclSrc->left + cx;
rclOffScreen.top = prclTrg->top;
rclOffScreen.right = prclTrg->left - cxPad;
// align offscreen rect to src
rclOffScreen.right += cAlign;
while (rclOnScreen.bottom < prclSrc->bottom)
{
cy = min(cy,(ULONG)(prclSrc->bottom - rclOnScreen.bottom));
ASSERT(cy != 0, "DrvSaveScreenBits: vCopyRects (cy == 0)\n");
rclOnScreen.top = rclOnScreen.bottom;
rclOnScreen.bottom += cy;
rclOffScreen.bottom = rclOffScreen.top + cy; // in case cy is shorter
// on last strip
rclOffScreen.left = rclOffScreen.right + cxPad;
rclOffScreen.right = rclOffScreen.left + cx;
if (rclOffScreen.right > (prclTrg->right + (LONG)cAlign))
{
RIP("DrvSaveScreenBits: "
"vCopyRects can't fit src into trg (horizontal)\n");
}
if (bIsSave)
{
// save
pptlSrcTmp = (POINTL *) &rclOnScreen;
prclTrgTmp = &rclOffScreen;
DISPDBG((1,"DrvSaveScreenBits (h save): "));
}
else
{
// restore
pptlSrcTmp = (POINTL *) &rclOffScreen;
prclTrgTmp = &rclOnScreen;
DISPDBG((1,"DrvSaveScreenBits (h restore): "));
}
DISPDBG((1,"%08x,%08x,%08x,%08x %lux%lu\n",
rclOffScreen.left,
rclOffScreen.top,
rclOffScreen.right,
rclOffScreen.bottom,
rclOffScreen.right - rclOffScreen.left,
rclOffScreen.bottom - rclOffScreen.top
));
ASSERT(((prclTrgTmp->left ^ pptlSrcTmp->x) &
(PLANAR_PELS_PER_CPU_ADDRESS - 1)) == 0,
"DrvSaveScreenBits (h): Src and Target are not aligned\n");
DrvCopyBits(pso, // psoDst (screen)
pso, // psoSrc (screen)
NULL, // pco (none)
NULL, // pxlo (none)
prclTrgTmp, // prclDst
pptlSrcTmp); // pptlSrc
}
}
else
{
// we don't need to break it up at all
cx = prclSrc->right - prclSrc->left;
cy = prclSrc->bottom - prclSrc->top;
ASSERT(cx != 0, "DrvSaveScreenBits: vCopyRects (save width == 0)\n");
ASSERT(cy != 0, "DrvSaveScreenBits: vCopyRects (save height == 0)\n");
rclOffScreen.left = prclTrg->left;
rclOffScreen.right = prclTrg->left + cx;
rclOffScreen.top = prclTrg->top;
rclOffScreen.bottom = prclTrg->top + cy;
// align offscreen rect to src
rclOffScreen.left += cAlign;
rclOffScreen.right += cAlign;
if (bIsSave)
{
// save
pptlSrcTmp = (POINTL *) prclSrc;
prclTrgTmp = &rclOffScreen;
DISPDBG((1,"DrvSaveScreenBits (save): "));
}
else
{
// restore
pptlSrcTmp = (POINTL *) &rclOffScreen;
prclTrgTmp = prclSrc;
DISPDBG((1,"DrvSaveScreenBits (restore): "));
}
DISPDBG((1,"%08x,%08x,%08x,%08x %lux%lu\n",
rclOffScreen.left,
rclOffScreen.top,
rclOffScreen.right,
rclOffScreen.bottom,
rclOffScreen.right - rclOffScreen.left,
rclOffScreen.bottom - rclOffScreen.top
));
ASSERT(((prclTrgTmp->left ^ pptlSrcTmp->x) &
(PLANAR_PELS_PER_CPU_ADDRESS - 1)) == 0,
"DrvSaveScreenBits: Src and Target are not aligned\n");
DrvCopyBits(pso, // psoDst (screen)
pso, // psoSrc (screen)
NULL, // pco (none)
NULL, // pxlo (none)
prclTrgTmp, // prclDst
pptlSrcTmp); // pptlSrc
}
return;
}
/******************************Public*Routine******************************\
* ulSaveOrRestoreBits(pso, ppdev,prcl,bIsSave) *
* *
* Saves or restores the specified area of the screen *
* *
\**************************************************************************/
ULONG ulSaveOrRestoreBits(SURFOBJ *pso, PPDEV ppdev, RECTL * prcl, BOOL bIsSave)
{
ULONG dxDstBottom, dyDstBottom; // width, height of bottom edge off screen area
ULONG dxDstRight, dyDstRight; // width, height of right edge off screen area
ULONG dxSrc, dySrc; // width, height of screen area to copy
RECTL rclSrcRight; // portion of *prcl to go into right edge area
RECTL rclSrcBottom; // portion of *prcl to go into bottom edge area
ULONG dxPadBottom; // width of spacer required to keep all copies
// after the first aligned in the bottom
// rectangle
//
// Saves bits from visible VGA memory in unused VGA memory
//
dxDstBottom = ppdev->rclSavedBitsBottom.right - ppdev->rclSavedBitsBottom.left;
dyDstBottom = ppdev->rclSavedBitsBottom.bottom - ppdev->rclSavedBitsBottom.top;
dxDstRight = ppdev->rclSavedBitsRight.right - ppdev->rclSavedBitsRight.left;
dyDstRight = ppdev->rclSavedBitsRight.bottom - ppdev->rclSavedBitsRight.top;
dxSrc = prcl->right - prcl->left;
dySrc = prcl->bottom - prcl->top;
// see if rect fits in lower rect, unbroken
// this is the most common case!
if (dySrc <= dyDstBottom && dxSrc <= dxDstBottom)
{
// YES!
DISPDBG((1,"DrvSaveScreenBits: bits all fit into bottom rect\n"));
vCopyRects(pso,
ppdev,
prcl,
&ppdev->rclSavedBitsBottom,
0,
bIsSave);
return(SAVED_OFFSCREEN_ID);
}
// see if rect fits in right rect, unbroken
if (dySrc <= dyDstRight && dxSrc <= dxDstRight)
{
// YES!
DISPDBG((1,"DrvSaveScreenBits: bits all fit into right rect\n"));
vCopyRects(pso,
ppdev,
prcl,
&ppdev->rclSavedBitsRight,
0,
bIsSave);
return(SAVED_OFFSCREEN_ID);
}
//
// before we bother to break it up, see if it could even POSSIBLY fit
//
if ((dxSrc * dySrc) > ((dxDstRight * dyDstRight) + (dxDstBottom * dyDstBottom)))
{
// Forget it bud. There are more bytes to save than we have total.
// Don't bother checking for best fit.
return(0);
}
// ARGGGHHHH!
//
// split source rectangle into two rectangles and see if they fit
//
rclSrcRight = rclSrcBottom = *prcl;
//
// see how many strips of height dySrc we can get into the rclDstRight
// (of height dyDstRight) and then divide the rclSrc rectangles so
// that rclSrcRight has that many strips and rclSrcBottom has what's left
//
rclSrcBottom.left = rclSrcRight.right =
min(rclSrcBottom.right,
rclSrcRight.left + (LONG)(dxDstRight * (dyDstRight/dySrc)));
//
// FYI: rclSrcRight WILL fit into ppdev->rclSavedBitsBottom because that's
// how its size was determined
//
// dxPadBottom = (-x)&(PLANAR_PELS_PER_CPU_ADDRESS-1) where x is the width of
// the rectangle that we want to break up and put into the bottom offscreen
// area. Therefore, ((rclSrcBottom.right-rclSrcBottom.left)+dxPadBottom)
// will be a number of pels that is a DWORD multiple.
dxPadBottom = (rclSrcBottom.left-rclSrcBottom.right) &
(PLANAR_PELS_PER_CPU_ADDRESS - 1);
if (((rclSrcBottom.right-rclSrcBottom.left) == 0) ||
((dySrc/dyDstBottom) <
(dxDstBottom/((rclSrcBottom.right-rclSrcBottom.left)+dxPadBottom))))
{
//
// rclSrcBottom fits into ppdev->rclSavedBitsBottom
//
if ((rclSrcRight.right - rclSrcRight.left) > 0)
{
//
// there is data that should go into the right edge area
//
vCopyRects(pso,
ppdev,
&rclSrcRight,
&ppdev->rclSavedBitsRight,
0,
bIsSave);
}
if (((rclSrcBottom.right - rclSrcBottom.left) > 0) &&
((rclSrcBottom.bottom - rclSrcBottom.top) > 0))
{
//
// there is data that should go into the bottom area
//
vCopyRects(pso,
ppdev,
&rclSrcBottom,
&ppdev->rclSavedBitsBottom,
dxPadBottom,
bIsSave);
}
return(SAVED_OFFSCREEN_ID);
}
// All that @#!&ing work, and we just barely missed fitting in.
return(0);
}