i_system.c

The source code of Doom legacy for windows

byte*   I_AllocLow(int length)
{
    byte*       mem;

    mem = (byte *)malloc (length);
    memset (mem,0,length);
    return mem;

}

#define MOUSE2
/* Secondary Mouse*/
#ifdef MOUSE2
_go32_dpmi_seginfo oldmouseinfo,newmouseinfo;
boolean mouse2_started=0;
USHORT  mouse2port;
byte    mouse2irq;
volatile int     handlermouse2buttons;
volatile int     handlermouse2x,handlermouse2y;
// internal use
volatile int     bytenum;
volatile byte    combytes[8];

//
// support a secondary mouse without mouse driver !
//
// take from the PC-GPE by Mark Feldman
static void I_MicrosoftMouseIntHandler()
{
  char   dx,dy;
  byte   inbyte;

  // Get the port byte
  inbyte = inportb(mouse2port);

  // Make sure we are properly "synched"
  if((inbyte & 64)== 64 || bytenum>7)
      bytenum = 0;

  // Store the byte and adjust bytenum
  combytes[bytenum] = inbyte;
  bytenum++;

  // Have we received all 3 bytes?
  if(bytenum==3)
  {
      // Yes, so process them
      dx = ((combytes[0] & 3) << 6) + combytes[1];
      dy = ((combytes[0] & 12) << 4) + combytes[2];
      handlermouse2x+= dx;
      handlermouse2y+= dy;
      handlermouse2buttons = (combytes[0] & (32+16)) >>4;
  }
  else
  if(bytenum==4) // for logitech 3 buttons
  {
      if(combytes[3] & 32)
          handlermouse2buttons |= 4;
      else
          handlermouse2buttons &= ~4;
  }

  // Acknowledge the interrupt
  outportb(0x20,0x20);
}
END_OF_FUNCTION(I_MicrosoftMouseIntHandler);

// wait ms milliseconde
void I_Delay(int ms)
{
    tic_t  starttime;

    if(timer_started)
    {
       starttime=I_GetTime()+(TICRATE*ms)/1000;
       while(starttime>=I_GetTime())
          ;
    }
    else
        delay(ms);
}

//
//  Removes the mouse2 handler.
//
void I_ShutdownMouse2()
{
    event_t event;
    int i;

    if( !mouse2_started )
        return;

    outportb(mouse2port+4,0x00);   // shutdown mouse (DTR & RTS = 0)
    I_Delay(1);
    outportb(mouse2port+1,0x00);   // disable COM interuption

    asm("cli");
    _go32_dpmi_set_protected_mode_interrupt_vector(mouse2irq, &oldmouseinfo);
    _go32_dpmi_free_iret_wrapper(&newmouseinfo);
    asm("sti");

    handlermouse2x=handlermouse2y=handlermouse2buttons=0;
    // emulate the up of all mouse buttons
    for(i=0;i<MOUSEBUTTONS;i++)
    {
        event.type=ev_keyup;
        event.data1=KEY_2MOUSE1+i;
        D_PostEvent(&event);
    }

    mouse2_started=false;
}

byte   ComIrq[4]={0x0c,0x0b,0x0c,0x0b};
USHORT ComPort[4]={0x3F8,0x2F8,0x3E8,0x2E8};
//
//  Installs the mouse2 handler.
//
void I_StartupMouse2()
{
    int i;
    boolean  found;
    __dpmi_regs r;

    if( mouse2_started )
        I_ShutdownMouse2();

    if(!cv_usemouse2.value)
        return;

    handlermouse2x=handlermouse2y=handlermouse2buttons=0;

    mouse2irq =ComIrq[cv_mouse2port.value-1];
    mouse2port=ComPort[cv_mouse2port.value-1];
    CONS_Printf("Using %s (irq %d, port 0x%x)\n",cv_mouse2port.string,mouse2irq-8,mouse2port);
    r.x.ax=0x24;
    __dpmi_int(0x33,&r);
    if(r.h.cl+8==mouse2irq)
    {
        CONS_Printf("Irq conflict with mouse 1\n"
                    "Use mouse2port to change the port\n");
        return;
    }

    // install irq wrapper
    asm("cli");
    _go32_dpmi_get_protected_mode_interrupt_vector(mouse2irq, &oldmouseinfo);
    newmouseinfo.pm_selector=_go32_my_cs();
    newmouseinfo.pm_offset=(int)I_MicrosoftMouseIntHandler;
    _go32_dpmi_allocate_iret_wrapper(&newmouseinfo);
    _go32_dpmi_set_protected_mode_interrupt_vector(mouse2irq, &newmouseinfo);

    LOCK_VARIABLE(bytenum);
    LOCK_VARIABLE(handlermouse2x);
    LOCK_VARIABLE(handlermouse2y);
    LOCK_VARIABLE(handlermouse2buttons);
    LOCK_VARIABLE(mouse2port);
    _go32_dpmi_lock_data(combytes,sizeof(combytes));
    LOCK_FUNCTION(I_MicrosoftMouseIntHandler);
    asm("sti");

    outportb(mouse2port+4,0   );   // shutdown mouse (DTR & RTS = 0)
    I_Delay(1);
    outportb(mouse2port+1,0   );   // disable COM interuption
    I_Delay(1);
    outportb(mouse2port+3,0x80);   // change status of port +0 et +1
    I_Delay(1);                    // for baudrate programmation
    outportb(mouse2port  ,0x60);   // 1200 LSB
    I_Delay(1);
    outportb(mouse2port+1,0   );   // 1200 MSB
    I_Delay(1);
    outportb(mouse2port+3,0x02);   // set port protocol 7N1
    I_Delay(1);
    outportb(mouse2port+1,0x01);   // enable COM interuption
    I_Delay(1);
    outportb(0x21,0x0);

    // wait to be sure the mouse have shutdown
    I_Delay(100);

    outportb(mouse2port+4,0x0b);   // restart mouse
    i=I_GetTime()+TICRATE;
    found=cv_usemouse2.value==2;
    while (I_GetTime()<i || !found)
       if(combytes[0]!='M')
          found=true;

    if(found || cv_usemouse2.value==2)
    {
        CONS_Printf("Microsoft compatible Secondary Mouse detected\n");

    //register shutdown mouse2 code.
    I_AddExitFunc(I_ShutdownMouse2);
    mouse2_started = true;
    }
    else
    {
        CONS_Printf("Secondary Mouse not found\n");
        // remove irq wraper
        I_ShutdownMouse2();
    }
}
#endif

//  Initialise the mouse. Doesnt need to be shutdown.
//
void I_StartupMouse (void)
{
    __dpmi_regs r;

    // mouse detection may be skipped by setting usemouse false
    if(cv_usemouse.value == 0)
    {
        mouse_detected=false;
        I_ShutdownMouse2();
        return;
    }

    //detect mouse presence
    r.x.ax=0;
    __dpmi_int(0x33,&r);

    //added:03-01-98:
    if( r.x.ax == 0 && cv_usemouse.value != 2)
    {
        mouse_detected=false;
        CONS_Printf("\2I_StartupMouse: mouse not present.\n");
    }
    else
    {
        mouse_detected=true;

    //hide cursor
    r.x.ax=2;
    __dpmi_int(0x33,&r);

    //reset mickey count
    r.x.ax=0x0b;
    __dpmi_int(0x33,&r);
    }
}

void I_GetEvent (void)
{
    __dpmi_regs r;
    event_t event;

    int i;

#ifdef MOUSE2
    // mouse may be disabled during the game by setting usemouse false
    if (mouse2_started)
    {
        //mouse movement
        static byte lastbuttons2=0;

        // post key event for buttons
        if (handlermouse2buttons!=lastbuttons2)
        {
            int j=1,k;
            k=(handlermouse2buttons ^ lastbuttons2); // only changed bit to 1
            lastbuttons2=handlermouse2buttons;

            for(i=0;i<MOUSEBUTTONS;i++,j<<=1)
                if(k & j)
                {
                    if(handlermouse2buttons & j)
                       event.type=ev_keydown;
                    else
                       event.type=ev_keyup;
                    event.data1=KEY_2MOUSE1+i;
                    D_PostEvent(&event);
                }
        }

        if ((handlermouse2x!=0)||(handlermouse2y!=0))
        {
            event.type=ev_mouse2;
            event.data1=0;
//          event.data1=buttons;    // not needed
            event.data2=handlermouse2x<<1;
            event.data3=-handlermouse2y<<1;

            D_PostEvent(&event);
            handlermouse2x=0;
            handlermouse2y=0;
        }

    }
#endif
    if(mouse_detected)
    {
        //mouse movement
        int xmickeys,ymickeys,buttons;
        static int lastbuttons=0;

        r.x.ax=0x0b;           // ask the mouvement not the position
        __dpmi_int(0x33,&r);
        xmickeys=(signed short)r.x.cx;
        ymickeys=(signed short)r.x.dx;
        r.x.ax=0x03;
        __dpmi_int(0x33,&r);
        buttons=r.x.bx;

        // post key event for buttons
        if (buttons!=lastbuttons)
        {
            int j=1,k;
            k=(buttons ^ lastbuttons); // only changed bit to 1
            lastbuttons=buttons;

            for(i=0;i<MOUSEBUTTONS;i++,j<<=1)
                if(k & j)
                {
                    if(buttons & j)
                       event.type=ev_keydown;
                    else
                       event.type=ev_keyup;
                    event.data1=KEY_MOUSE1+i;
                    D_PostEvent(&event);
                }
        }

        if ((xmickeys!=0)||(ymickeys!=0))
        {
          event.type=ev_mouse;
          event.data1=0;
//          event.data1=buttons;    // not needed
          event.data2=xmickeys;
          event.data3=-ymickeys;

          D_PostEvent(&event);
        }

    }
    //joystick
    if (joystick_detected)
    {
        static int lastjoybuttons=0;
        int joybuttons;

        poll_joystick();
        // I assume that true is 1
        joybuttons=joy_b1+(joy_b2<<1)+(joy_b3<<2)+(joy_b4<<3)
                         +(joy_b5<<4)+(joy_b6<<5)+(joy_b7<<6)+(joy_b8<<7);

        switch(joy_hat) {
          case JOY_HAT_UP   : joybuttons|=1<<10;break;
          case JOY_HAT_DOWN : joybuttons|=1<<11;break;
          case JOY_HAT_LEFT : joybuttons|=1<<12;break;
          case JOY_HAT_RIGHT: joybuttons|=1<<13;break;
        }

        // post key event for buttons
        if(joybuttons!=lastjoybuttons)
        {
            int j=1,k;
            k=(joybuttons ^ lastjoybuttons); // only changed bit to 1
            lastjoybuttons=joybuttons;

            for(i=0;i<JOYBUTTONS;i++,j<<=1)
                if(k & j)          // test the eatch bit and post the corresponding event
                {
                    if(joybuttons & j)
                       event.type=ev_keydown;
                    else
                       event.type=ev_keyup;
                    event.data1=KEY_JOY1+i;
                    D_PostEvent(&event);
                }
        }

        event.type=ev_joystick;
        event.data1=0;
        event.data2=0;
        event.data3=0;

        if(joy_left)
           event.data2=-1;
        if(joy_right)
           event.data2=1;
        if(joy_up)
           event.data3=-1;
        if(joy_down)
           event.data3=1;

        D_PostEvent(&event);
    }
}

//
//  Timer user routine called at ticrate.
//
void I_TimerISR (void)
{
   //  IO_PlayerInput();      // old doom did that
   ticcount++;

}
END_OF_FUNCTION(I_TimerISR);


//added:08-01-98: we don't use allegro_exit() so we have to do it ourselves.
void I_ShutdownTimer (void)