reactos/subsystems/ntvdm/bop.c

   1 /*
   2  * COPYRIGHT:       GPL - See COPYING in the top level directory
   3  * PROJECT:         ReactOS Virtual DOS Machine
   4  * FILE:            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 "emulator.h"
  15 #include "bop.h"
  16
  17 /* PRIVATE VARIABLES **********************************************************/
  18
  19 /*
  20  * This is the list of registered BOP handlers.
  21  */
  22 static EMULATOR_BOP_PROC BopProc[EMULATOR_MAX_BOP_NUM] = { NULL };
  23
  24 /* PUBLIC FUNCTIONS ***********************************************************/
  25
  26 VOID RegisterBop(BYTE BopCode, EMULATOR_BOP_PROC BopHandler)
  27 {
  28     BopProc[BopCode] = BopHandler;
  29 }
  30
  31 VOID WINAPI EmulatorBiosOperation(PFAST486_STATE State, UCHAR BopCode)
  32 {
  33     WORD StackSegment, StackPointer;
  34     LPWORD Stack;
  35
  36     /* Get the SS:SP */
  37     StackSegment = State->SegmentRegs[FAST486_REG_SS].Selector;
  38     StackPointer = State->GeneralRegs[FAST486_REG_ESP].LowWord;
  39
  40     /* Get the stack */
  41     Stack = (LPWORD)SEG_OFF_TO_PTR(StackSegment, StackPointer);
  42
  43     /* Call the BOP handler */
  44     if (BopProc[BopCode] != NULL)
  45         BopProc[BopCode](Stack);
  46     else
  47         DPRINT("Invalid BOP code: 0x%02X\n", BopCode);
  48 }
  49
  50 /* EOF */