dict.h

#ifndef _DICT_H_
#define _DICT_H_
#include <stddef.h>

typedef unsigned long hash_t;
hash_t dict_strhash(const char *s);

struct dict_entry {
  hash_t d_hash;
  char *d_key;
};

struct dict {
  struct dict_entry *d_table;
  size_t d_table_len;
  size_t d_load;
  size_t d_count;
};

#define DEFINE_DICT(d) \
  struct dict d = { .d_table = NULL, }

/* The count argument is only a hint. */
int dict_init(struct dict *dict, size_t hint);

/* dict_destory() is valid for dicts defined by DEFINE_DICT() or
   initialized by dict_init().  It does not free entry keys. */
void dict_destroy(struct dict *dict, void (*key_dtor)(void*));

struct dict_entry *dict_entry_ref(struct dict *dict, hash_t hash, const char *key);
int dict_entry_set(struct dict *dict, struct dict_entry *ent, hash_t hash, char *key);
char *dict_entry_remv(struct dict *dict, struct dict_entry *ent, int may_resize);
static inline void dict_allow_resize(struct dict *dict, size_t hint)
{
  /* TODO, maybe. */
}

char *dict_ref(struct dict *dict, const char *key);
int dict_set(struct dict *dict, char *key);
char *dict_remv(struct dict *dict, const char *key);

/* Returns only non-NULL keys. */
char *dict_for_each(struct dict *dict, size_t *i);
struct dict_entry *dict_for_each_ref(struct dict *dict, size_t *i);

#endif