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#include <sys/types.h>

#include "go32.h"

#include "dpmi.h"

#include "dos.h"

u_short _go32_my_cs()

{

  asm("movw %cs,%ax");

}

u_short _go32_my_ds()

{

  asm("movw %ds,%ax");

}

u_short _go32_my_ss()

{

  asm("movw %ss,%ax");

}

u_short _go32_conventional_mem_selector()

{

  return _go32_info_block.selector_for_linear_memory;

}

static _go32_dpmi_registers regs;

static volatile u_long ctrl_break_count = 0;

static int ctrl_break_hooked = 0;

static _go32_dpmi_seginfo old_vector;

static _go32_dpmi_seginfo new_vector;

static ctrl_break_isr(_go32_dpmi_registers *regs)

{

  ctrl_break_count ++;

}

u_long _go32_was_ctrl_break_hit()

{

  u_long cnt;

  _go32_want_ctrl_break(1);

  cnt = ctrl_break_count;

  ctrl_break_count = 0;

  return cnt;

}

void _go32_want_ctrl_break(int yes)

{

  if (yes)

  {

    if (ctrl_break_hooked)

      return;

    _go32_dpmi_get_real_mode_interrupt_vector(0x1b, &old_vector);

    new_vector.pm_offset = (int)ctrl_break_isr;

    _go32_dpmi_allocate_real_mode_callback_iret(&new_vector, &regs);

    _go32_dpmi_set_real_mode_interrupt_vector(0x1b, &new_vector);

    ctrl_break_count = 0;

    ctrl_break_hooked = 1;

  }

  else

  {

    if (!ctrl_break_hooked)

      return;

    _go32_dpmi_set_real_mode_interrupt_vector(0x1b, &old_vector);

    _go32_dpmi_free_real_mode_callback(&new_vector);

    ctrl_break_count = 0;

    ctrl_break_hooked = 0;

  }

}