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/*
* esh, the Unix shell with Lisp-like syntax.
* Copyright (C) 1999 Ivan Tkatchev
* This source code is under the GPL.
*/
/*
* A very simple hash table implementation, using "buckets".
*
* Pitfalls:
*
* + You cannot delete elements from the cache.
* + Calling "hash_put" or "hash_get" before "hash_init" likely
* means a segfault.
* + "hash_init" should always be called. Pass a NULL as the second
* argument if you don't want any initial data.
* + Calling"hash_init" more than once on the same hash table
* constitutes a giant memory leak!
* + You cannot free a hash table once you have called "hash_init"
* on it. (See previous pitfall.)
* + The argument to "hash_init" is terminated with a { NULL, NULL }
* + The hash table does not do any memory management -- i.e.
* the arguments to "hash_put" are not copied before they are inserted
* into the hash table.
* + "hash_put" returns the previous data with the same key, if any.
* It is your responsibility to free this data, if necessary.
* + "hash_inc_ref" and "hash_put_inc_ref" assume that the hash table
* holds only lists.
*/
#ifndef HASH_H
#define HASH_H
typedef struct hash_entry hash_entry;
typedef list** hash_table;
struct hash_entry {
char* key;
void* data;
};
extern void* hash_put(hash_table* t, char* key, void* data);
extern void* hash_put_inc_ref(hash_table* t, char* key, void* data);
extern void hash_init(hash_table* t, hash_entry data[]);
extern void* hash_get(hash_table* t, char* key);
extern void hash_free(hash_table* t,
void (*func1)(),
void (*func2)());
extern void hash_inc_ref(hash_table* t);
extern list* hash_keys(hash_table* t);
#endif
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