/*
        OS LAB assignment 1
*/
#include <stdio.h>
#include<stdlib.h>
#include<conio.h>
#include <dos.h>

void interrupt(*Int9Save) (void);
void interrupt(*Int8Save) (void);
void interrupt(*Int1Save) (void);   /* Pointer to function to store TRAP interrupt */

// Variables
volatile unsigned int secISR;
volatile unsigned int secISR_rec;
volatile unsigned int secGLOBAL;
int ISR[256];
int reqISR;
int IP;
int count;

//Override deafult interrupt
void interrupt h1(void){

    int idx;

      asm {
        push ax
        mov ax,[BP+2]
        mov IP,ax
        pop ax
      }

      idx=IP/4;
      ISR[idx]++;

      if(count==4){
          if(reqISR>=0 && reqISR<=255)
                printf("ISR[%d] = %d",reqISR,ISR[reqISR]);

        count=0;
        reqISR= -1;
      }
}

void interrupt h8(void){

    asm{
        PUSHF
        CALL DWORD PTR Int8Save
    }//asm
    printf("DEBUGGGG\n");
    secGLOBAL--; /*counter*/
    secISR_rec--;

    if (secISR_rec<=0){ // if secISR_rec passed, start again
        secISR_rec=secISR;

        count=0;
        reqISR= -1;
    }
}

void interrupt h9(void) {

    unsigned char c1;

    asm{
        PUSH AX
        MOV AH,0
        INT 16h
        MOV c1,AL
        POP AX
    }/* reading the button*/

            if(c1=='i' && count==0){
                count++;
            }
            else if(count==1 && c1<='2' && c1>='0'){
                count++;
                c1=(c1-'0')*100;
                reqISR=c1;
            }
            else if(count==2 && c1<='9' && c1>='0'){
                count++;
                c1=(c1-'0')*10;
                reqISR=reqISR+c1;
            }
            else if(count==3 && c1<='9' && c1>='0'){
                count++;
                c1=(c1-'0');
                reqISR=reqISR+c1;
            }
}

void interrupt_counter(int intTime, int time) {

    // give first values
    secISR = intTime*182 / 10;
    secGLOBAL = time*182 / 10;
    secISR_rec=secISR;


    Int9Save = getvect(9); // save old func
    Int8Save = getvect(8); // save old func
    Int1Save = getvect(1); // save old func

    setvect(9, h9);    // new func
    setvect(8, h8);    // new func
    setvect(1, h1);    // new func

        asm{//turn on the trap flag
                pushf
                pop ax
                or ax,100000000B
                push ax
                popf
        }
}
void main()
{
    int i;
    count=0;
    reqISR=-1;

    for(i=0;i<256;i++)
        ISR[i]=0;

    interrupt_counter(5,20);

    while (secGLOBAL>0);

    for(i=0;i<256;i++)
        printf("%d \n",ISR[i]);

    setvect(9, Int9Save);  // return to old func
    setvect(8, Int8Save);  // return to old func
    setvect(1, Int1Save);  // return to old func

        asm{
            pushf
            pop ax
            and ax,1111111011111111B
            push ax
            popf
        }

    system("PAUSE");

}