miscemu/emulate.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include "miscemu.h"
   4 #include "debug.h"
   5
   6 struct Win87EmInfoStruct
   7 {
   8     unsigned short Version;
   9     unsigned short SizeSaveArea;
  10     unsigned short WinDataSeg;
  11     unsigned short WinCodeSeg;
  12     unsigned short Have80x87;
  13     unsigned short Unused;
  14 };
  15
  16 /* Implementing this is easy cause Linux and *BSD* ALWAYS have a numerical
  17  * coprocessor. (either real or emulated on kernellevel)
  18  */
  19 /* win87em.dll also sets interrupt vectors: 2 (NMI), 0x34 - 0x3f (emulator
  20  * calls of standard libraries, see Ralph Browns interrupt list), 0x75
  21  * (int13 error reporting of coprocessor)
  22  */
  23
  24 /* have a look at /usr/src/linux/arch/i386/math-emu/ *.[ch] for more info
  25  * especially control_w.h and status_w.h
  26  */
  27 /* FIXME: Only skeletal implementation for now */
  28
  29 void WINAPI WIN87_fpmath( CONTEXT *context )
  30 {
  31     dprintf_info(int, "_fpmath: (cs:eip=%x:%lx es=%x bx=%04x ax=%04x dx==%04x)\n",
  32                  (WORD)CS_reg(context), EIP_reg(context),
  33                  (WORD)ES_reg(context), BX_reg(context),
  34                  AX_reg(context), DX_reg(context) );
  35
  36     switch(BX_reg(context))
  37     {
  38     case 0: /* install (increase instanceref) emulator, install NMI vector */
  39         AX_reg(context) = 0;
  40         break;
  41
  42     case 1: /* Init Emulator */
  43         AX_reg(context) = 0;
  44         break;
  45
  46     case 2: /* deinstall emulator (decrease instanceref), deinstall NMI vector
  47              * if zero. Every '0' call should have a matching '2' call.
  48              */
  49         AX_reg(context) = 0;
  50         break;
  51
  52     case 3:
  53         /*INT_SetHandler(0x3E,MAKELONG(AX,DX));*/
  54         break;
  55
  56     case 4: /* set control word (& ~(CW_Denormal|CW_Invalid)) */
  57         /* OUT: newset control word in AX */
  58         break;
  59
  60     case 5: /* return internal control word in AX */
  61         break;
  62
  63     case 6: /* round top of stack to integer using method AX & 0x0C00 */
  64         /* returns current controlword */
  65         break;
  66
  67     case 7: /* POP top of stack as integer into DX:AX */
  68         /* IN: AX&0x0C00 rounding protocol */
  69         /* OUT: DX:AX variable popped */
  70         {
  71             DWORD dw=0;
  72             /* I don't know much about asm() programming. This could be
  73              * wrong.
  74              */
  75 /* FIXME: could someone who really understands asm() fix this please? --AJ */
  76 /*            __asm__("fistp %0;wait" : "=m" (dw) : : "memory"); */
  77             dprintf_info(int,"emulate.c:On top of stack was %ld\n",dw);
  78             AX_reg(context) = LOWORD(dw);
  79             DX_reg(context) = HIWORD(dw);
  80         }
  81         break;
  82
  83     case 8: /* restore internal control words from emulator control word */
  84         break;
  85
  86     case 9: /* clear emu control word and some other things */
  87         break;
  88
  89     case 10: /* dunno. but looks like returning nr. of things on stack in AX */
  90         AX_reg(context) = 0;
  91         break;
  92
  93     case 11: /* just returns the installed flag in DX:AX */
  94         DX_reg(context) = 0;
  95         AX_reg(context) = 1;
  96         break;
  97
  98     case 12: /* save AX in some internal state var */
  99         break;
 100
 101     default: /* error. Say that loud and clear */
 102         AX_reg(context) = DX_reg(context) = 0xFFFF;
 103         break;
 104     }
 105 }
 106
 107
 108 void WINAPI WIN87_WinEm87Info(struct Win87EmInfoStruct *pWIS,
 109                               int cbWin87EmInfoStruct)
 110 {
 111   dprintf_info(int, "__WinEm87Info(%p,%d)\n",pWIS,cbWin87EmInfoStruct);
 112 }
 113
 114 void WINAPI WIN87_WinEm87Restore(void *pWin87EmSaveArea,
 115                                  int cbWin87EmSaveArea)
 116 {
 117   dprintf_info(int, "__WinEm87Restore(%p,%d)\n",
 118         pWin87EmSaveArea,cbWin87EmSaveArea);
 119 }
 120
 121 void WINAPI WIN87_WinEm87Save(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
 122 {
 123   dprintf_info(int, "__WinEm87Save(%p,%d)\n",
 124         pWin87EmSaveArea,cbWin87EmSaveArea);
 125 }