Untitled

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>

int main() {
    printf("\n\nPASS 2\n");


    char locctr[10], label[10], opcode[10], operand[10];
    char optab_opcode[10], optab_machine_code[10];
    char symtab_label[10], symtab_address[10];
    int object_count = 0, starting_address, ending_address = 0, program_length = 0;
    bool opcode_found = false;
    bool label_found = false;


    FILE *input_file, *output_file, *symtab_file, *optab_file;


    input_file = fopen("intermediate.txt", "r");
    output_file = fopen("output.txt", "w");
    symtab_file = fopen("symtab.txt", "r");
    optab_file = fopen("optab.txt", "r");


    if (input_file == NULL || output_file == NULL || symtab_file == NULL || optab_file == NULL) {
        printf("Error! File not found!");
        exit(1);
    } else {
        printf("All files opened successfully!\n");
    }


    fscanf(input_file, "%s %s %s %s", locctr, label, opcode, operand);
    starting_address = atoi(operand);

    printf("\nOUTPUT:\n\n");


    while (!feof(input_file)) {
        if (!(strcmp(opcode, "START") == 0 || strcmp(opcode, "END") == 0 ||
              strcmp(opcode, "RESW") == 0 || strcmp(opcode, "RESB") == 0)) {
            object_count++;
        }


        if (strcmp(opcode, "END") != 0) {
            ending_address = atoi(locctr);
        }

        fscanf(input_file, "%s %s %s %s", locctr, label, opcode, operand);
    }


    program_length = ending_address - starting_address;


    rewind(input_file);
    fscanf(input_file, "%s %s %s %s", locctr, label, opcode, operand);

    printf("H %s 00%s 0000%d\n", label, operand, program_length);
    fprintf(output_file, "H %s 00%s 0000%d\n", label, operand, program_length);

    printf("T 00%s %d ", operand, (object_count * 6) / 2);
    fprintf(output_file, "T 00%s %d ", operand, (object_count * 6) / 2);

    while (!feof(input_file)) {

        if (strcmp(opcode, "START") == 0 || strcmp(opcode, "END") == 0 ||
            strcmp(opcode, "RESW") == 0 || strcmp(opcode, "RESB") == 0) {
            fscanf(input_file, "%s %s %s %s", locctr, label, opcode, operand);
            continue;
        } else {

            rewind(optab_file);
            opcode_found = false;

            while (fscanf(optab_file, "%s %s", optab_opcode, optab_machine_code) != EOF) {
                if (strcmp(opcode, optab_opcode) == 0) {
                    opcode_found = true;
                    break;
                }
            }

            if (opcode_found) {

                rewind(symtab_file);
                label_found = false;

                while (fscanf(symtab_file, "%s %s", symtab_label, symtab_address) != EOF) {
                    if (strcmp(symtab_label, operand) == 0) {
                        label_found = true;
                        break;
                    }
                }

                if (label_found) {
                    printf("%s%s ", optab_machine_code, symtab_address);
                    fprintf(output_file, "%s%s ", optab_machine_code, symtab_address);
                } else {
                    printf("Error! Label not found in symtab!\n");
                    exit(1);
                }
            } else if (strcmp(opcode, "WORD") == 0) {
                printf("%06d ", atoi(operand));
                fprintf(output_file, "%06d ", atoi(operand));
            } else if (strcmp(opcode, "BYTE") == 0) {
                if (operand[0] == 'C') {
                    for (int i = 2; i < strlen(operand) - 1; i++) {
                        printf("%02X", operand[i]);
                        fprintf(output_file, "%02X", operand[i]);
                    }
                } else if (operand[0] == 'X') {
                    for (int i = 2; i < strlen(operand) - 1; i++) {
                        printf("%c", operand[i]);
                        fprintf(output_file, "%c", operand[i]);
                    }
                }
                printf(" ");
                fprintf(output_file, " ");
            } else {
                printf("Error! Invalid opcode!\n");
                exit(1);
            }
        }
        fscanf(input_file, "%s %s %s %s", locctr, label, opcode, operand);
    }

    printf("\nE 00%d\n", starting_address);
    fprintf(output_file, "\nE 00%d\n", starting_address);


    fclose(input_file);
    fclose(output_file);
    fclose(symtab_file);
    fclose(optab_file);

    return 0;
}