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 The Inbv* and the Vid* functions from BOOTVID.DLL and NTOSKRNL.EXE are not
 documented, but they are similar. Some assumptions were drawn from the ezine
 6 of the 29A group - Ratter's TAICHI-Virus.

 Here are my findings!

 (c) 2004 by -=Assarbad=-
 Published under the GPL
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

HAL functions: Inbv*
---------------------------
// Allows to "prefilter" strings?
void
InbvInstallDisplayStringFilter(
  PVOID DisplayStringFilterProc // points presumably to some routine (prototype unknown!)
);

// Checks wether the HAL owns the display?
BOOLEAN
InbvIsBootDriverInstalled(void);

// Aquires the display ownership for the caller?
void
InbvAcquireDisplayOwnership(void);

// Used by the HAL to reset the display into textmode for the BSOD ;)
BOOLEAN InbvResetDisplay(void);

// Fills portions of the screen (or the complete screen) with a given
// color. It uses pixel as the unit!!!
void
InbvSolidColorFill(
  ULONG Left, // Meaning of the parameters should be clear ;)
  ULONG Top,
  ULONG Right,
  ULONG Bottom,
  DWORD Color
);

// Shows an ASCII/ANSI string. Not yet test wether there's a difference
// between OEM and normal ANSI string.
BOOLEAN
InbvDisplayString(
  PCHAR Str
);

// Sets the text color for the next output operations.
ULONG
InbvSetTextColor(
  DWORD Color
);

// Sets the portion of the screen which is being scrolled. This is how
// Windows 2000 implements the nice "graphical" boot screen!
// It uses pixel as the unit!!!
void
InbvSetScrollRegion(
  ULONG Left, // Meaning of the parameters should be clear ;)
  ULONG Top,
  ULONG Right,
  ULONG Bottom
);


BOOLEAN
InbvEnableDisplayString(
  BOOLEAN Enable
);
---------------------------

BOOTVID functions: Vid*
---------------------------
void
VidSolidColorFill(
  ULONG Left,
  ULONG Top,
  ULONG Right,
  ULONG Bottom,
  DWORD Color
);

void
VidDisplayString(
  PCHAR Str
);

void
VidResetDisplay(void);

BOOLEAN
VidInitialize(BOOLEAN SetMode);

void
VidBitBlt(
  PBYTE Buffer,
  ULONG x,
  ULONG y
);

void
VidSetScrollRegion(
  ULONG Left,
  ULONG Top,
  ULONG Right,
  ULONG Bottom
);

void
VidCleanUp(void);

void
VidDisplayStringXY(
  PCHAR Str,
  ULONG X,
  ULONG Y,
  BOOLEAN NoBgColor
);

ULONG
VidSetTextColor(
  ULONG Color
);
---------------------------

Maybe I missed some function, but I hope the parameters are correct?! Calling
them using these prototypes worked find for me!

One serious problem for me was the missing LIB file for the BOOTVID.DLL!
I tried to create one using a custom .DEF-file and the LIB utility from MS,
but it wouldn't work like this :-/

I will further investigate how exactly the Inbv* functions work.

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