reactos/subsystems/mvdm/ntvdm/cpu/bop.c

   1 /*
   2  * COPYRIGHT:       GPL - See COPYING in the top level directory
   3  * PROJECT:         ReactOS Virtual DOS Machine
   4  * FILE:            subsystems/mvdm/ntvdm/cpu/bop.c
   5  * PURPOSE:         BIOS Operation Handlers
   6  * PROGRAMMERS:     Aleksandar Andrejevic <theflash AT sdf DOT lonestar DOT org>
   7  *                  Hermes Belusca-Maito (hermes.belusca@sfr.fr)
   8  */
   9
  10 /* INCLUDES *******************************************************************/
  11
  12 #define NDEBUG
  13
  14 #include "ntvdm.h"
  15 #include "emulator.h"
  16 #include "bop.h"
  17
  18 /* PRIVATE VARIABLES **********************************************************/
  19
  20 /*
  21  * This is the list of registered BOP handlers.
  22  */
  23 static EMULATOR_BOP_PROC BopProc[EMULATOR_MAX_BOP_NUM] = { NULL };
  24
  25 /* PUBLIC FUNCTIONS ***********************************************************/
  26
  27 VOID RegisterBop(BYTE BopCode, EMULATOR_BOP_PROC BopHandler)
  28 {
  29     BopProc[BopCode] = BopHandler;
  30 }
  31
  32 VOID FASTCALL EmulatorBiosOperation(PFAST486_STATE State, UCHAR BopCode)
  33 {
  34     WORD StackSegment, StackPointer;
  35     LPWORD Stack;
  36
  37     /* Get the SS:SP */
  38     StackSegment = State->SegmentRegs[FAST486_REG_SS].Selector;
  39     StackPointer = State->GeneralRegs[FAST486_REG_ESP].LowWord;
  40
  41     /* Get the stack */
  42     Stack = (LPWORD)SEG_OFF_TO_PTR(StackSegment, StackPointer);
  43
  44     /* Call the BOP handler */
  45     if (BopProc[BopCode] != NULL)
  46         BopProc[BopCode](Stack);
  47     else
  48         DPRINT1("Invalid BOP code: 0x%02X\n", BopCode);
  49 }
  50
  51 /* EOF */