Library

library.c

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

#define MAX 100
#define EXIT_CHOICE 10

#define USERS_FILE "users.txt"
#define BOOKS_FILE "books.txt"

struct customer {
  char fname[MAX];
  char lname[MAX];
  int id;
};

typedef struct customer customer_t;

struct book{
  char title[MAX];
  char author[MAX];
  int id;
};

typedef struct book book_t;


int customer_count = 0;
int book_count = 0;

int cust_id = 1;
int book_id = 1;

int get_input () {
  int c;
  printf(
      "Choose from the following options :\n"
       "1. Display all registered users\n"
       "2. Display all books\n"
       "3. Display all borrowers\n"
       "4. Add a new user\n"
       "5. Add a new book\n"
       "6. Issue a new book\n"
       "7. Accept back a book\n"
       "8. Generate fine\n"
       "10. Exit\n\n\n"
      );
  scanf("%d", &c);
  return c;
}

void display_users() {
  FILE *file = fopen(USERS_FILE, "rb");
  customer_t customers[MAX];
  fread(customers, sizeof(customer_t), customer_count, file);

  for (int i = 0; i < customer_count; i++) {
    printf("%d\t%s\t%s\n", customers[i].id, customers[i].fname, customers[i].lname);
  }
  fclose(file);
}

void add_user() {
  printf("Enter name:\n");
  customer_t customer;

  if (fgets(customer.fname, MAX, stdin) != NULL) {
    customer.id = cust_id++;
    FILE *file = fopen(USERS_FILE, "wb");
    fwrite(&customer, sizeof(customer), 1, file);
    fclose(file);
  } 
}

void display_books(){
  FILE *file = fopen(BOOKS_FILE,"rb");
  book_t books[MAX];
  fread(books,sizeof(book_t), book_count, file);
  for(int i = 0 ; i<book_count ; i++){
    printf("%d | %s | %s ",books[i].id,books[i].title,books[i].author);
  }
}

void add_book(){
 printf("Enter title and Author\n");
 book_t book;
 if(fgets(book.title, MAX, stdin) != NULL || fgets(book.author, MAX, stdin) != NULL){
  book.id = book_id++;
  FILE *file = fopen(BOOKS_FILE, "wb");
  fwrite(&book, sizeof(book), 1, file);
 }
}

int main () {
  int choice;
  while ((choice = get_input()) != EXIT_CHOICE) {
    switch (choice) {
      case 1: display_users();
	      break;
      case 2: display_books();
	      break;
      case 3: add_book();
	      break;
      case 4: add_user();
	      break;
      
    }
  }
  printf("Saving data..\n");
  return 0;
}