relocation.c

#include<stdio.h>
#include<string.h>
#include <stdlib.h>
char bit[30];
char bitmask[20];

void bitmask_convert(char mask[])
{
	int len;
	len=strlen(mask);
	strcpy(bit,"");

	int i;

	for(i=0;i<len;++i)
	{
		switch(mask[i])
		{
		
			case '0': strcat(bit,"0000");
				  break;
			case '1': strcat(bit,"0001");
				  break;
			case '2': strcat(bit,"0010");
                                  break;
			case '3': strcat(bit,"0011");
                                  break;
			case '4': strcat(bit,"0100");
                                  break;
			case '5': strcat(bit,"0101");
                                  break;
			case '6': strcat(bit,"0110");
                                  break;
			case '7': strcat(bit,"0111");
                                  break;
			case '8': strcat(bit,"1000");
                                  break;
			case '9': strcat(bit,"1001");
                                  break;
			case 'A': strcat(bit,"1010");
                                  break;
			case 'B': strcat(bit,"1011");
                                  break;
			case 'C': strcat(bit,"1100");
                                  break;
	
			case 'D': strcat(bit,"1101");
                                  break;
			case 'E': strcat(bit,"1110");
                                  break;

			case 'F': strcat(bit,"1111");
                                  break;

			default : break;
		}

	}
	
}





void main()
{

	FILE *objptr;
	int start,addr;
	char rec[20];
	char name[20];
	int modif_obj_code;

	char first[3];
	char second[5];
	
	int bitmask_index=0;

	int i;
	////char bitmask[20];
	//char bit[20];

	int  add,len;

	printf("ENTER THE STARTING ADDRESS OF THE PROGRAM\n");
	scanf("%X",&start);
	addr=start;
	
	objptr=fopen("program.txt","r");

       fscanf(objptr,"%s",rec);

       if(strcmp(rec,"H")==0)
       {
	      // printf("HEADER RECORD");
	       fscanf(objptr,"%s",name);
	       fscanf(objptr,"%X",&add);
	       fscanf(objptr,"%X",&len);
	      printf("\nPROGRAM NAME=%s\n\n",name);

	      printf(" ADDRESS   OBJECT CODE \n");
	      printf("____________________________\n");
       }
       else
	{
		printf("INAVLID OBJECT CODE FORMAT\n");
		fclose(objptr);
		exit(1);
	}
      
       strcpy(rec,"");
       
	
       fscanf(objptr,"%s",rec);

       while(strcmp(rec,"E")!=0)
       {
	       //fscanf(objptr,"%s",rec);
	       if(strcmp(rec,"T")==0)
	       {
		       fscanf(objptr,"%X",&add);
		       fscanf(objptr,"%X",&len);
		       fscanf(objptr,"%s",bitmask);
		       add+=start;
		       bitmask_index=0;
		       bitmask_convert(bitmask);
		       fscanf(objptr,"%s",rec);
	       }

		if(bit[bitmask_index]=='1')
	 	{
			//printf("NEED RELOCATION\n");
			
		//	modif_obj_code=atoi(rec);
		//	modif_obj_code+=start;
		//	printf("%X\t%X\n",add,modif_obj_code);
		//	strcpy(first,"");
		//	strcpy(second,"");
			for(i=0;i<6;++i)
			{
				if(i<2)
				{
					
					first[i]=rec[i];
					
				}
				else
				{
					second[i-2]=rec[i];

				}
			}
			first[2]='\0';
			second[4]='\0';
			modif_obj_code=strtol(second,NULL,16);
			modif_obj_code+=start;

			printf("%X\t%s%X\n",add,first,modif_obj_code);
				
		}
		else
		{
			printf("%X\t%s\n",add,rec);

		}		
	       //printf("%s\n",rec);
		add+=3;
		bitmask_index++;
		
	       fscanf(objptr,"%s",rec);
       }
       

       fclose(objptr);
}


/*
H COPY 000000 00107A
T 000000 1E FFC 140033 481039 100036 280030 300015 481061 3C0003 20002A 1C0039 30002D
T 002500 15 E00 1D0036 481061 180033 4C1000 801000 601003
E 000000
OUTPUT
______________
ENTER THE STARTING ADDRESS OF THE PRROGRAM
4000
PROGRAM NAME=COPY
 ADDRESS   OBJECT CODE 
____________________________
4000	144033
4003	485039
4006	104036
4009	284030
400C	304015
400F	485061
4012	3C4003
4015	20402A
4018	1C4039
401B	30402D
6500	1D4036
6503	485061
6506	184033
6509	4C1000
650C	801000
650F	601003
*/