simulator.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "simulator_files/memory.h"
#include "simulator_files/func.h"

//reads the object code from the file and loads it into the memory
int loader(FILE *objfile)
{
    int startAddress = relocationCounter;
    int memaddress = relocationCounter;
    while (!feof(objfile))
    {
        char *line;
        line = (char *)malloc(1000 * sizeof(char));
        fgets(line, 1000, objfile);

        char *pos;
        if ((pos = strchr(line, '\n')) != NULL)
            *pos = '\0';

        if(!strcmp(line,""))
        {
            continue;
        }

        printf("%s\n",line);//debug print

        char *p;
        p = (char *)malloc(10 * sizeof(char));
        p = strtok(line, " ");

        char *opcode;
        opcode = (char *)malloc(10 * sizeof(char));
        strcpy(opcode, p);

        strcpy(memory[memaddress], opcode);
        memaddress++;
    }
    relocationCounter = memaddress;

    for (int i = startAddress; i < relocationCounter; i++)
        memory[i];

    return startAddress;
}

//runs the program
int run(int startAddress)
{
    pc = startAddress;
    while (1)
    {
        int returncode = function(memory[pc]);
        if (returncode == 0)
        {
            return 0;
        }
        readnext();
    }
}

//Output for the user
void showOutput()
{
    printf("-----------------------------------------\n");
    printf("\n\nOUTPUT:\n");
    while (1)
    {
        printf("\nEnter the memory address (hexadecimal): ");
        char addr[10];
        scanf("%s", addr);
        getchar();
        fflush(stdin);
        printf("Value at memory[%s] = %s\n", addr, memory[hex_decimal(addr)]);
        printf("Enter more addresses(y/n): ");
        char choice;
        scanf("%c", &choice);
        getchar();
        fflush(stdin);
        if (choice != 'y' && choice != 'Y')
            break;
    }
}

//Taking data input from user
void userInput()
{
    char upperlimit[5] = "3FFF";
    char lowerlimit[5] = "2000";
    printf("-----------------------------------------\n");
    printf("\n\nINPUT:\n");
    printf("(Input data must be placed from %sh to %sh memory locations)\n",lowerlimit,upperlimit);
    while (1)
    {
        printf("\nEnter data (y/n): ");
        char choice;
        scanf("%c", &choice);
        getchar();
        fflush(stdin);
        if (choice != 'y' && choice != 'Y')
            break;
        printf("\nEnter the memory address (hexadecimal): ");
        char addr[10];
        scanf("%s", addr);
        getchar();
        fflush(stdin);
        if (hex_decimal(lowerlimit) <= hex_decimal(addr) && hex_decimal(addr) < hex_decimal(upperlimit))
        {
            printf("Enter the value (hexdecimal): ");
            char val[3];
            scanf("%s", val);
            getchar();
            fflush(stdin);

            strcpy(memory[hex_decimal(addr)], val);
        }
        else
        {
            printf("Input data must be placed from %sh to %sh memory locations\n",lowerlimit,upperlimit);
        }
        
    }
}

int main(int argc, char *argv[])
{

    if (argc != 2)
    {
        printf("Please Enter object file as argument\n");
        exit(0);
    }

    //objfilename contains the objectcode file path
    char *objfilename = argv[1];

    FILE *objfile = fopen(objfilename, "r");

    //check if file doesnot exit
    if (objfile == NULL)
    {
        printf("File not found!\n");
        exit(0);
    }

    initializeMachine();

    userInput();

    printf("Simulation started\n");

    int startAddress = loader(objfile);

    printf("Running prog\n");

    run(startAddress);

    fclose(objfile);

    printf("\nacc : %d\n",acc);

    showOutput();

    FILE* out=fopen("memory.txt","w");
    for(int i=0;i<10000;i++)
    {
        fprintf(out,"Value at address %x = %s\n",i,memory[i]);
    }
    return 0;
}