offscreen.c File Reference

#include <vgaddi.h>

Include dependency graph for offscreen.c:

Go to the source code of this file.

Functions
VOID	VGADDI_BltFromSavedScreenBits (IN ULONG DestX, IN ULONG DestY, IN PSAVED_SCREEN_BITS Src, IN ULONG SizeX, IN ULONG SizeY)
VOID	VGADDI_BltToSavedScreenBits (IN PSAVED_SCREEN_BITS Dest, IN ULONG SourceX, IN ULONG SourceY, IN ULONG SizeX, IN ULONG SizeY)
VOID	VGADDI_FreeSavedScreenBits (PSAVED_SCREEN_BITS SavedBits)
PSAVED_SCREEN_BITS	VGADDI_AllocSavedScreenBits (ULONG Size)
VOID	VGADDI_InitializeOffScreenMem (IN ULONG Start, IN ULONG Length)

Variables
static LIST_ENTRY	SavedBitsList

Function Documentation

VGADDI_AllocSavedScreenBits()

PSAVED_SCREEN_BITS VGADDI_AllocSavedScreenBits

(

ULONG

Size

)

Definition at line 121 of file offscreen.c.

{
    PSAVED_SCREEN_BITS Current;
    PLIST_ENTRY CurrentEntry;
    PSAVED_SCREEN_BITS Best;
    PSAVED_SCREEN_BITS New;

    Best = NULL;
    CurrentEntry = SavedBitsList.Flink;
    while (CurrentEntry != &SavedBitsList)
    {
        Current = CONTAINING_RECORD(CurrentEntry, SAVED_SCREEN_BITS, ListEntry);

        if (Current->Free && Current->Size >= Size &&
            (Best == NULL || (Current->Size - Size) < (Best->Size - Size)))
        {
            Best = Current;
        }

        CurrentEntry = CurrentEntry->Flink;
    }

    if (!Best)
      return NULL;

    if (Best->Size == Size)
    {
        Best->Free = FALSE;
        return Best;
    }
    else
    {
        New = EngAllocMem(0, sizeof(SAVED_SCREEN_BITS), ALLOC_TAG);
        New->Free = FALSE;
        New->Offset = Best->Offset + Size;
        New->Size = Size;
        Best->Size -= Size;
        InsertHeadList(&Best->ListEntry, &New->ListEntry);
        return New;
    }
}

Referenced by DrvSetPointerShape(), and InitPointer().

VGADDI_BltFromSavedScreenBits()

VOID VGADDI_BltFromSavedScreenBits	(	IN ULONG	DestX,
		IN ULONG	DestY,
		IN PSAVED_SCREEN_BITS	Src,
		IN ULONG	SizeX,
		IN ULONG	SizeY
	)

Definition at line 20 of file offscreen.c.

{
    PUCHAR DestOffset;
    PUCHAR SrcOffset;
    ULONG i, j;

    /* Select write mode 1. */
    WRITE_PORT_UCHAR((PUCHAR)GRA_I, 5);
    WRITE_PORT_UCHAR((PUCHAR)GRA_D, 1);

    SrcOffset = (PUCHAR)vidmem + Src->Offset;
    for (i = 0; i < SizeY; i++)
    {
        DestOffset = (PUCHAR)vidmem + (i + DestY) * 80 + (DestX >> 3);
        //FIXME: in the loop below we should treat the case when SizeX is not divisible by 8, i.e. partial bytes
        for (j = 0; j < SizeX>>3; j++, SrcOffset++, DestOffset++)
        {
            (VOID)READ_REGISTER_UCHAR(SrcOffset);
            WRITE_REGISTER_UCHAR(DestOffset, 0);
        }
    }

    /* Select write mode 2. */
    WRITE_PORT_UCHAR((PUCHAR)GRA_I, 5);
    WRITE_PORT_UCHAR((PUCHAR)GRA_D, 2);
}

Referenced by VGADDI_HideCursor().

VGADDI_BltToSavedScreenBits()

VOID VGADDI_BltToSavedScreenBits	(	IN PSAVED_SCREEN_BITS	Dest,
		IN ULONG	SourceX,
		IN ULONG	SourceY,
		IN ULONG	SizeX,
		IN ULONG	SizeY
	)

Definition at line 53 of file offscreen.c.

{
    PUCHAR DestOffset;
    PUCHAR SrcOffset;
    ULONG i, j;

    /* Select write mode 1. */
    WRITE_PORT_UCHAR((PUCHAR)GRA_I, 5);
    WRITE_PORT_UCHAR((PUCHAR)GRA_D, 1);

    DestOffset = (PUCHAR)vidmem + Dest->Offset;

    for (i = 0; i < SizeY; i++)
    {
        SrcOffset = (PUCHAR)vidmem + (SourceY + i) * 80 + (SourceX >> 3);
        //FIXME: in the loop below we should treat the case when SizeX is not divisible by 8, i.e. partial bytes
        for (j = 0; j < SizeX>>3; j++, SrcOffset++, DestOffset++)
        {
            (VOID)READ_REGISTER_UCHAR(SrcOffset);
            WRITE_REGISTER_UCHAR(DestOffset, 0);
        }
    }

    /* Select write mode 2. */
    WRITE_PORT_UCHAR((PUCHAR)GRA_I, 5);
    WRITE_PORT_UCHAR((PUCHAR)GRA_D, 2);
}

Referenced by VGADDI_ShowCursor().

VGADDI_FreeSavedScreenBits()

VOID VGADDI_FreeSavedScreenBits

(

PSAVED_SCREEN_BITS

SavedBits

)

Definition at line 87 of file offscreen.c.

{
    SavedBits->Free = TRUE;

    if (SavedBits->ListEntry.Blink != &SavedBitsList)
    {
        PSAVED_SCREEN_BITS Previous;

        Previous = CONTAINING_RECORD(SavedBits->ListEntry.Blink,
                                     SAVED_SCREEN_BITS, ListEntry);
        if (Previous->Free)
        {
            Previous->Size += SavedBits->Size;
            RemoveEntryList(&SavedBits->ListEntry);
            EngFreeMem(SavedBits);
            SavedBits = Previous;
        }
    }
    if (SavedBits->ListEntry.Flink != &SavedBitsList)
    {
        PSAVED_SCREEN_BITS Next;

        Next = CONTAINING_RECORD(SavedBits->ListEntry.Flink, SAVED_SCREEN_BITS,
                                 ListEntry);
        if (Next->Free)
        {
            SavedBits->Size += Next->Size;
            RemoveEntryList(&SavedBits->ListEntry);
            EngFreeMem(SavedBits);
        }
    }
}

Referenced by DrvSetPointerShape().

VGADDI_InitializeOffScreenMem()

VOID VGADDI_InitializeOffScreenMem	(	IN ULONG	Start,
		IN ULONG	Length
	)

Definition at line 164 of file offscreen.c.

{
    PSAVED_SCREEN_BITS FreeBits;

    InitializeListHead(&SavedBitsList);

    FreeBits = EngAllocMem(0, sizeof(SAVED_SCREEN_BITS), ALLOC_TAG);
    FreeBits->Free = TRUE;
    FreeBits->Offset = Start;
    FreeBits->Size = Length;
    InsertHeadList(&SavedBitsList, &FreeBits->ListEntry);
}

Referenced by DrvEnableDriver().

Variable Documentation

SavedBitsList

LIST_ENTRY SavedBitsList

static

Definition at line 15 of file offscreen.c.

Referenced by VGADDI_AllocSavedScreenBits(), VGADDI_FreeSavedScreenBits(), and VGADDI_InitializeOffScreenMem().