grep/regex/hashtable.c

64   hashtable *tbl;
69   tbl = malloc(sizeof(hashtable));
70   if (tbl == NULL)
73   tbl->entries = calloc(sizeof(hashtable_entry *), table_size);
74   if (tbl->entries == NULL)
77   tbl->table_size = table_size;
78   tbl->usage = 0;
79   tbl->key_size = key_size;
80   tbl->value_size = value_size;
82   return (tbl);
85   free(tbl);
93  * Places the key-value pair to the hashtable tbl.
105 hashtable_put(hashtable *tbl, const void *key, const void *value)
109   if (tbl->table_size == tbl->usage)
115   hash = hash32_buf(key, tbl->key_size, hash) % tbl->table_size;
125       if (tbl->entries[hash] == NULL)
127       else if (memcmp(tbl->entries[hash]->key, key, tbl->key_size) == 0)
129 	  memcpy(tbl->entries[hash]->value, value, tbl->value_size);
134       if (++hash == tbl->table_size)
140   tbl->entries[hash] = malloc(sizeof(hashtable_entry));
141   if (tbl->entries[hash] == NULL)
147   tbl->entries[hash]->key = malloc(tbl->key_size);
148   if (tbl->entries[hash]->key == NULL)
154   tbl->entries[hash]->value = malloc(tbl->value_size);
155   if (tbl->entries[hash]->value == NULL)
161   memcpy(tbl->entries[hash]->key, key, tbl->key_size);
162   memcpy(tbl->entries[hash]->value, value, tbl->value_size);
163   tbl->usage++;
170   free(tbl->entries[hash]->key);
172   free(tbl->entries[hash]);
179 **hashtable_lookup(const hashtable *tbl, const void *key)
183   hash = hash32_buf(key, tbl->key_size, hash) % tbl->table_size;
187       if (tbl->entries[hash] == NULL)
189       else if (memcmp(key, tbl->entries[hash]->key, tbl->key_size) == 0)
192 	  return (&tbl->entries[hash]);
195       if (++hash == tbl->table_size)
201  * Retrieves the value for key from the hash table tbl and places
207 hashtable_get(hashtable *tbl, const void *key, void *value)
211   entry = hashtable_lookup(tbl, key);
218   memcpy(value, (*entry)->value, tbl->value_size);
225  * tbl. Returns HASH_OK if the entry has been found and removed
229 hashtable_remove(hashtable *tbl, const void *key)
233   entry = hashtable_lookup(tbl, key);
245   tbl->usage--;
251  * Frees the resources associated with the hash table tbl.
254 hashtable_free(hashtable *tbl)
256   if (tbl == NULL)
259   for (unsigned int i = 0; i < tbl->table_size; i++)
260     if ((tbl->entries[i] != NULL))
262 	free(tbl->entries[i]->key);
263 	free(tbl->entries[i]->value);
266   free(tbl->entries);