/* Demonstrate bit-wise operations usage for flags handling */
/* Set/Reset bit, Add/Combine, Reverse, Swap, Check */
#include <stdlib.h>
#include <stdio.h>

void AccountStatus(int Status, char * Name);

/* one bit flags */
#define ACTIVATED      0x0001
#define VIP            0x0002
#define PAST_DUE       0x0004
#define OVER_LIMIT     0x0008
#define STOLEN         0x0010
#define LOST           0x0020
#define PREFERRED_RATE 0x0040

int main (void)
{
  /* combine basic flags to initial values - OR */
  int Card1 = VIP | ACTIVATED | PREFERRED_RATE;
  int Card2 = OVER_LIMIT | PAST_DUE | PREFERRED_RATE;
  char *Name1 = "Mark McKenzie";
  char *Name2 = "Marian Purue";

  printf("\nBefore update\n");
  AccountStatus(Card1, Name1);
  Card1 &= ~(VIP | PREFERRED_RATE);     /* clear VIP and pref rate bits */
  Card1 |= OVER_LIMIT;                  /* set overlimit bit */
  Card1 ^= ACTIVATED;                   /* reverse activated bit */
  printf("\nAfter update\n");
  AccountStatus(Card1, Name1);

  printf("\nBefore update\n");
  AccountStatus(Card2, Name2);
  Card2 &= ~PAST_DUE;                   /* clear past due bit */
  Card2 |= LOST;                        /* set lost bit */
  printf("\nAfter update\n");
  AccountStatus(Card2, Name2);

  printf("\nBefore swap\n");
  AccountStatus(Card2, Name2);
  AccountStatus(Card1, Name1);
  Card1 ^= Card2;                       /* 3 xor's will exchange 2 values */
  Card2 ^= Card1;
  Card1 ^= Card2;
  printf("\nAfter swap\n");
  AccountStatus(Card2, Name2);
  AccountStatus(Card1, Name1);

  /* or masks together to test for any of the set of conditions */
  if (Card1 & (OVER_LIMIT | PAST_DUE))
    printf("\n%s is a deadbeat\n", Name1);

  return(0);
}

void AccountStatus(int Status, char *Name)
{
  printf("Account status for %s\n%s%s%s%s%s%s%s\n", Name,
         (Status & ACTIVATED)      ? "Activated\n"      : "Not Activated\n",
         (Status & VIP)            ? "VIP\n"            : "",
         (Status & PAST_DUE)       ? "Past Due\n"       : "",
         (Status & OVER_LIMIT)     ? "Overlimit\n"      : "",
         (Status & STOLEN)         ? "***Stolen***\n"   : "",
         (Status & LOST)           ? "***Lost***\n"     : "",
         (Status & PREFERRED_RATE) ? "Preferred rate\n" : "Standard rate\n");
}