seamlessrdp/ClientDLL/hash.h

/* HW: HenkJan Wolthuis, 1997 */
#ifndef HASH__H
#define HASH__H

#include <stddef.h>             /* For size_t   */
/*
** A hash table consists of an array of these buckets.      Each bucket
** holds a copy of the key, a pointer to the data associated with the
** key, and a pointer to the next bucket that collided with this one,
** if there was one.
*/

typedef struct bucket {
      char *key;
      void *data;
      struct bucket *next;
} bucket;

/*
** This is what you actually declare an instance of to create a table.
** You then call 'construct_table' with the address of this structure,
** and a guess at the size of the table.  Note that more nodes than this
** can be inserted in the table, but performance degrades as this
** happens.  Performance should still be quite adequate until 2 or 3
** times as many nodes have been inserted as the table was created with.
*/

typedef struct hash_table {
      size_t size;
      size_t count;     /* HW */
      bucket **table;
} hash_table;

/*
** This is used to construct the table.  If it doesn't succeed, it sets
** the table's size to 0, and the pointer to the table to NULL.
*/
/* HW: returns NULL if it fails */
hash_table *hash_construct_table(hash_table *table,size_t size);

/*
** Inserts a pointer to 'data' in the table, with a copy of 'key' as its
** key.  Note that this makes a copy of the key, but NOT of the
** associated data.
*/

void *hash_insert(char *key,void *data,struct hash_table *table);

/*
** Returns a pointer to the data associated with a key.  If the key has
** not been inserted in the table, returns NULL.
*/

void *hash_lookup(char *key,struct hash_table *table);

/*
** Deletes an entry from the table.  Returns a pointer to the data that
** was associated with the key so the calling code can dispose of it
** properly.
*/

void *hash_del(char *key,struct hash_table *table);

/*
** Goes through a hash table and calls the function passed to it
** for each node that has been inserted.  The function is passed
** a pointer to the key, and a pointer to the data associated
** with it.
*/

void hash_enumerate( hash_table *table,void (*func)(char *,void *));

/* HW: same as above, but sorted output ( sorted on 'key') */
int hash_sorted_enum( hash_table *table, void(*func)(char *, void*));

/*
** Frees a hash table.  For each node that was inserted in the table,
** it calls the function whose address it was passed, with a pointer
** to the data that was in the table.  The function is expected to
** free the data.  Typical usage would be:
** free_table(&table, free);
** if the data placed in the table was dynamically allocated, or:
** free_table(&table, NULL);
** if not.  ( If the parameter passed is NULL, it knows not to call
** any function with the data. )
*/

void hash_free_table(hash_table *table, void (*func)(void *));

#endif /* HASH__H */
1	/* HW: HenkJan Wolthuis, 1997 */
2	#ifndef HASH__H
3	#define HASH__H
4
5	#include <stddef.h> /* For size_t */
6	/*
7	** A hash table consists of an array of these buckets. Each bucket
8	** holds a copy of the key, a pointer to the data associated with the
9	** key, and a pointer to the next bucket that collided with this one,
10	** if there was one.
11	*/
12
13	typedef struct bucket {
14	char *key;
15	void *data;
16	struct bucket *next;
17	} bucket;
18
19	/*
20	** This is what you actually declare an instance of to create a table.
21	** You then call 'construct_table' with the address of this structure,
22	** and a guess at the size of the table. Note that more nodes than this
23	** can be inserted in the table, but performance degrades as this
24	** happens. Performance should still be quite adequate until 2 or 3
25	** times as many nodes have been inserted as the table was created with.
26	*/
27
28	typedef struct hash_table {
29	size_t size;
30	size_t count; /* HW */
31	bucket **table;
32	} hash_table;
33
34	/*
35	** This is used to construct the table. If it doesn't succeed, it sets
36	** the table's size to 0, and the pointer to the table to NULL.
37	*/
38	/* HW: returns NULL if it fails */
39	hash_table hash_construct_table(hash_table table,size_t size);
40
41	/*
42	** Inserts a pointer to 'data' in the table, with a copy of 'key' as its
43	** key. Note that this makes a copy of the key, but NOT of the
44	** associated data.
45	*/
46
47	void hash_insert(char key,void data,struct hash_table table);
48
49	/*
50	** Returns a pointer to the data associated with a key. If the key has
51	** not been inserted in the table, returns NULL.
52	*/
53
54	void hash_lookup(char key,struct hash_table *table);
55
56	/*
57	** Deletes an entry from the table. Returns a pointer to the data that
58	** was associated with the key so the calling code can dispose of it
59	** properly.
60	*/
61
62	void hash_del(char key,struct hash_table *table);
63
64	/*
65	** Goes through a hash table and calls the function passed to it
66	** for each node that has been inserted. The function is passed
67	** a pointer to the key, and a pointer to the data associated
68	** with it.
69	*/
70
71	void hash_enumerate( hash_table table,void (func)(char ,void ));
72
73	/* HW: same as above, but sorted output ( sorted on 'key') */
74	int hash_sorted_enum( hash_table table, void(func)(char , void));
75
76	/*
77	** Frees a hash table. For each node that was inserted in the table,
78	** it calls the function whose address it was passed, with a pointer
79	** to the data that was in the table. The function is expected to
80	** free the data. Typical usage would be:
81	** free_table(&table, free);
82	** if the data placed in the table was dynamically allocated, or:
83	** free_table(&table, NULL);
84	** if not. ( If the parameter passed is NULL, it knows not to call
85	** any function with the data. )
86	*/
87
88	void hash_free_table(hash_table table, void (func)(void *));
89
90	#endif /* HASH__H */