Sweden-Number/miscemu/emulate.c

129 lines
3.6 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include "miscemu.h"
#include "stddebug.h"
/* #define DEBUG_INT */
#include "debug.h"
struct Win87EmInfoStruct
{
unsigned short Version;
unsigned short SizeSaveArea;
unsigned short WinDataSeg;
unsigned short WinCodeSeg;
unsigned short Have80x87;
unsigned short Unused;
};
/* Implementing this is easy cause Linux and *BSD* ALWAYS have a numerical
* coprocessor. (either real or emulated on kernellevel)
*/
/* win87em.dll also sets interrupt vectors: 2 (NMI), 0x34 - 0x3f (emulator
* calls of standard libraries, see Ralph Browns interrupt list), 0x75
* (int13 error reporting of coprocessor)
*/
/* have a look at /usr/src/linux/arch/i386/math-emu/ *.[ch] for more info
* especially control_w.h and status_w.h
*/
/* FIXME: Only skeletal implementation for now */
void WIN87_fpmath( SIGCONTEXT *context )
{
dprintf_int(stddeb, "_fpmath: (cs:eip=%x:%lx es=%x bx=%04x ax=%04x dx==%04x)\n",
CS_reg(context), EIP_reg(context),
ES_reg(context), BX_reg(context),
AX_reg(context), DX_reg(context) );
switch(BX_reg(context))
{
case 0: /* install (increase instanceref) emulator, install NMI vector */
AX_reg(context) = 0;
break;
case 1: /* Init Emulator */
AX_reg(context) = 0;
break;
case 2: /* deinstall emulator (decrease instanceref), deinstall NMI vector
* if zero. Every '0' call should have a matching '2' call.
*/
AX_reg(context) = 0;
break;
case 3:
/*INT_SetHandler(0x3E,MAKELONG(AX,DX));*/
break;
case 4: /* set control word (& ~(CW_Denormal|CW_Invalid)) */
/* OUT: newset control word in AX */
break;
case 5: /* return internal control word in AX */
break;
case 6: /* round top of stack to integer using method AX & 0x0C00 */
/* returns current controlword */
break;
case 7: /* POP top of stack as integer into DX:AX */
/* IN: AX&0x0C00 rounding protocol */
/* OUT: DX:AX variable popped */
{
DWORD dw=0;
/* I don't know much about asm() programming. This could be
* wrong.
*/
/* FIXME: could someone who really understands asm() fix this please? --AJ */
/* __asm__("fistp %0;wait" : "=m" (dw) : : "memory"); */
dprintf_int(stddeb,"emulate.c:On top of stack was %ld\n",dw);
AX_reg(context) = LOWORD(dw);
DX_reg(context) = HIWORD(dw);
}
break;
case 8: /* restore internal control words from emulator control word */
break;
case 9: /* clear emu control word and some other things */
break;
case 10: /* dunno. but looks like returning nr. of things on stack in AX */
AX_reg(context) = 0;
break;
case 11: /* just returns the installed flag in DX:AX */
DX_reg(context) = 0;
AX_reg(context) = 1;
break;
case 12: /* save AX in some internal state var */
break;
default: /* error. Say that loud and clear */
AX_reg(context) = DX_reg(context) = 0xFFFF;
break;
}
}
void
WIN87_WinEm87Info(struct Win87EmInfoStruct *pWIS, int cbWin87EmInfoStruct)
{
dprintf_int(stddeb, "__WinEm87Info(%p,%d)\n",pWIS,cbWin87EmInfoStruct);
}
void
WIN87_WinEm87Restore(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
{
dprintf_int(stddeb, "__WinEm87Restore(%p,%d)\n",
pWin87EmSaveArea,cbWin87EmSaveArea);
}
void
WIN87_WinEm87Save(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
{
dprintf_int(stddeb, "__WinEm87Save(%p,%d)\n",
pWin87EmSaveArea,cbWin87EmSaveArea);
}