subsystems/ntvdm/ntvdm.c

   1 /*
   2  * COPYRIGHT:       GPL - See COPYING in the top level directory
   3  * PROJECT:         ReactOS Virtual DOS Machine
   4  * FILE:            ntvdm.c
   5  * PURPOSE:         Virtual DOS Machine
   6  * PROGRAMMERS:     Aleksandar Andrejevic <theflash AT sdf DOT lonestar DOT org>
   7  */
   8
   9 /* INCLUDES *******************************************************************/
  10
  11 #define NDEBUG
  12
  13 #include "ntvdm.h"
  14 #include "emulator.h"
  15 #include "cmos.h"
  16 #include "bios.h"
  17 #include "speaker.h"
  18 #include "vga.h"
  19 #include "dos.h"
  20 #include "timer.h"
  21 #include "pic.h"
  22 #include "ps2.h"
  23
  24 /*
  25  * Activate this line if you want to be able to test NTVDM with:
  26  * ntvdm.exe <program>
  27  */
  28 #define TESTING
  29
  30 /* PUBLIC VARIABLES ***********************************************************/
  31
  32 BOOLEAN VdmRunning = TRUE;
  33 LPVOID BaseAddress = NULL;
  34
  35 /* PUBLIC FUNCTIONS ***********************************************************/
  36
  37 VOID DisplayMessage(LPCWSTR Format, ...)
  38 {
  39     WCHAR Buffer[256];
  40     va_list Parameters;
  41
  42     va_start(Parameters, Format);
  43     _vsnwprintf(Buffer, 256, Format, Parameters);
  44     DPRINT1("\n\nNTVDM Subsystem\n%S\n\n", Buffer);
  45     MessageBoxW(NULL, Buffer, L"NTVDM Subsystem", MB_OK);
  46     va_end(Parameters);
  47 }
  48
  49 BOOL WINAPI ConsoleCtrlHandler(DWORD ControlType)
  50 {
  51     switch (ControlType)
  52     {
  53         case CTRL_C_EVENT:
  54         case CTRL_BREAK_EVENT:
  55         {
  56             /* Perform interrupt 0x23 */
  57             EmulatorInterrupt(0x23);
  58             break;
  59         }
  60         default:
  61         {
  62             /* Stop the VDM if the user logs out or closes the console */
  63             VdmRunning = FALSE;
  64         }
  65     }
  66     return TRUE;
  67 }
  68
  69 INT wmain(INT argc, WCHAR *argv[])
  70 {
  71     INT i;
  72     CHAR CommandLine[DOS_CMDLINE_LENGTH];
  73     LARGE_INTEGER StartPerfCount;
  74     LARGE_INTEGER Frequency, LastTimerTick, LastRtcTick, Counter;
  75     LONGLONG TimerTicks;
  76     DWORD StartTickCount, CurrentTickCount;
  77     DWORD LastClockUpdate;
  78     DWORD LastVerticalRefresh;
  79     DWORD LastCyclePrintout;
  80     DWORD Cycles = 0;
  81
  82     /* Set the handler routine */
  83     SetConsoleCtrlHandler(ConsoleCtrlHandler, TRUE);
  84
  85 #ifndef TESTING
  86     UNREFERENCED_PARAMETER(argc);
  87     UNREFERENCED_PARAMETER(argv);
  88
  89     /* The DOS command line must be ASCII */
  90     WideCharToMultiByte(CP_ACP, 0, GetCommandLine(), -1, CommandLine, sizeof(CommandLine), NULL, NULL);
  91 #else
  92     if (argc == 2 && argv[1] != NULL)
  93     {
  94         WideCharToMultiByte(CP_ACP, 0, argv[1], -1, CommandLine, sizeof(CommandLine), NULL, NULL);
  95     }
  96     else
  97     {
  98         wprintf(L"\nReactOS Virtual DOS Machine\n\n"
  99                 L"Usage: NTVDM <executable>\n");
 100         return 0;
 101     }
 102 #endif
 103
 104     DPRINT1("\n\n\nNTVDM - Starting '%s'...\n\n\n", CommandLine);
 105
 106     /* Initialize the emulator */
 107     if (!EmulatorInitialize())
 108     {
 109         wprintf(L"FATAL: Failed to initialize the CPU emulator\n");
 110         goto Cleanup;
 111     }
 112
 113     /* Initialize the performance counter (needed for hardware timers) */
 114     if (!QueryPerformanceFrequency(&Frequency))
 115     {
 116         wprintf(L"FATAL: Performance counter not available\n");
 117         goto Cleanup;
 118     }
 119
 120     /* Initialize the PIC */
 121     if (!PicInitialize())
 122     {
 123         wprintf(L"FATAL: Failed to initialize the PIC.\n");
 124         goto Cleanup;
 125     }
 126
 127     /* Initialize the PIT */
 128     if (!PitInitialize())
 129     {
 130         wprintf(L"FATAL: Failed to initialize the PIT.\n");
 131         goto Cleanup;
 132     }
 133
 134     /* Initialize the CMOS */
 135     if (!CmosInitialize())
 136     {
 137         wprintf(L"FATAL: Failed to initialize the VDM CMOS.\n");
 138         goto Cleanup;
 139     }
 140
 141     /* Initialize the PC Speaker */
 142     SpeakerInitialize();
 143
 144     /* Initialize the system BIOS */
 145     if (!BiosInitialize())
 146     {
 147         wprintf(L"FATAL: Failed to initialize the VDM BIOS.\n");
 148         goto Cleanup;
 149     }
 150
 151     /* Initialize the VDM DOS kernel */
 152     if (!DosInitialize())
 153     {
 154         wprintf(L"FATAL: Failed to initialize the VDM DOS kernel.\n");
 155         goto Cleanup;
 156     }
 157
 158     /* Start the process from the command line */
 159     if (!DosCreateProcess(CommandLine, 0))
 160     {
 161         DisplayMessage(L"Could not start program: %S", CommandLine);
 162         goto Cleanup;
 163     }
 164
 165     /* Find the starting performance and tick count */
 166     StartTickCount = GetTickCount();
 167     QueryPerformanceCounter(&StartPerfCount);
 168
 169     /* Set the different last counts to the starting count */
 170     LastClockUpdate = LastVerticalRefresh = LastCyclePrintout = StartTickCount;
 171
 172     /* Set the last timer ticks to the current time */
 173     LastTimerTick = LastRtcTick = StartPerfCount;
 174
 175     /* Main loop */
 176     while (VdmRunning)
 177     {
 178         DWORD PitResolution = PitGetResolution();
 179         DWORD RtcFrequency = RtcGetTicksPerSecond();
 180
 181         /* Get the current number of ticks */
 182         CurrentTickCount = GetTickCount();
 183
 184         if ((PitResolution <= 1000) && (RtcFrequency <= 1000))
 185         {
 186             /* Calculate the approximate performance counter value instead */
 187             Counter.QuadPart = StartPerfCount.QuadPart
 188                                + (CurrentTickCount - StartTickCount)
 189                                * (Frequency.QuadPart / 1000);
 190         }
 191         else
 192         {
 193             /* Get the current performance counter value */
 194             QueryPerformanceCounter(&Counter);
 195         }
 196
 197         /* Get the number of PIT ticks that have passed */
 198         TimerTicks = ((Counter.QuadPart - LastTimerTick.QuadPart)
 199                      * PIT_BASE_FREQUENCY) / Frequency.QuadPart;
 200
 201         /* Update the PIT */
 202         if (TimerTicks > 0)
 203         {
 204             PitDecrementCount(TimerTicks);
 205             LastTimerTick = Counter;
 206         }
 207
 208         /* Check for RTC update */
 209         if ((CurrentTickCount - LastClockUpdate) >= 1000)
 210         {
 211             RtcTimeUpdate();
 212             LastClockUpdate = CurrentTickCount;
 213         }
 214
 215         /* Check for RTC periodic tick */
 216         if ((Counter.QuadPart - LastRtcTick.QuadPart)
 217             >= (Frequency.QuadPart / (LONGLONG)RtcFrequency))
 218         {
 219             RtcPeriodicTick();
 220             LastRtcTick = Counter;
 221         }
 222
 223         /* Check for vertical retrace */
 224         if ((CurrentTickCount - LastVerticalRefresh) >= 15)
 225         {
 226             VgaRefreshDisplay();
 227             LastVerticalRefresh = CurrentTickCount;
 228         }
 229
 230         /* Horizontal retrace occurs as fast as possible */
 231         VgaHorizontalRetrace();
 232
 233         /* Continue CPU emulation */
 234         for (i = 0; (i < STEPS_PER_CYCLE) && VdmRunning; i++)
 235         {
 236             EmulatorStep();
 237             Cycles++;
 238         }
 239
 240         if ((CurrentTickCount - LastCyclePrintout) >= 1000)
 241         {
 242             DPRINT1("NTVDM: %lu Instructions Per Second\n", Cycles);
 243             LastCyclePrintout = CurrentTickCount;
 244             Cycles = 0;
 245         }
 246     }
 247
 248     /* Perform another screen refresh */
 249     VgaRefreshDisplay();
 250
 251 Cleanup:
 252     SpeakerCleanup();
 253     BiosCleanup();
 254     CmosCleanup();
 255     EmulatorCleanup();
 256
 257     DPRINT1("\n\n\nNTVDM - Exiting...\n\n\n");
 258
 259     return 0;
 260 }
 261
 262 /* EOF */