/* Hash table structures and constants */
#ifndef __HASH_H
#define __HASH_H


/* Hash table entry */
struct hash_entry{
  /* Key used for hashing */
  void* key;
  /* Additional data */
  void* data;
  /* Flag to show state of entry (VALID, EMPTY, DELETED) */
  int state;
  /* If this is entry with collisions where is next value,
     or if this is empty spot where is the next spot. This is hash index. */
  int next;
  /* If this is empty slot, what is its predecessor in list of empty slots */
  int prev;
};

/* Hash table 
   This is really an attempt to
   make classfull, reusable
   structure in C */
struct hash_table{
  /* Contents */
  struct hash_entry* entries;
  /* Number of entries */
  unsigned long size;
  unsigned long min_size;
  unsigned long max_size;
  /* Number of filled entries */
  unsigned long filled;
  /* Size of key */
  int key_size;
  /* Size of data */
  int data_size;
  /* Load factors for rehashing */
  double rehash_lf_high;
  double rehash_lf_low;
  /* Flag indicating that hash is dangerously full and 
     can not grow anymore. Then drastic cleaning has to
     be done */
  int FULL_ALERT;
  /* Points to the first empty spot, all empty spots are linked together */
  int empty;
  /* Function to check if entry can be deleted
     depending on urgency of deletion */
  int (*clean)(void*);
  /* Function to compare keys if they are same 
     it returns 1 if they are same, and 0 otherwise */
  int (*compare)(void*, void*);
  /* First hash function, for double hashing */
  unsigned long (*hash1)(void*,unsigned long);
  /* Sometimes it is useful to forbid rehashing */
  int no_rehash;
};

 struct subnet 
 {
   unsigned int ip;
   char checklist[256];
   int count;
   struct subnet *next;
};

/* Function prototypes, refer to implementation in hash.c for descriptions */
int test_prime(long);
void create_hash(struct hash_table**,  unsigned long, 
		 unsigned long, unsigned long, 
		 double, double, int, int, 
		 int (*)(void*), int (*)(void*,void*),
		 unsigned long (*)(void*,unsigned long));
void clean_table(struct hash_table*);
void rehash(int, struct hash_table*);
long insert(void*, struct hash_table*, int*);
long find(void*, struct hash_table*);
long delete(void*, struct hash_table*);
void check_rehash(struct hash_table*);

#define NEW 1
#define FAILED -1
#define EXISTING 2

#endif