const char *
metacache_add_string (const char *str) {
// printf ("n_strings=%d, n_inserts=%d, n_buckets=%d\n", n_strings, n_inserts, n_buckets);
uint32_t h = metacache_get_hash_sdbm (str);
metacache_str_t *data = metacache_find_in_bucket (h % HASH_SIZE, str);
n_inserts++;
if (data) {
data->refcount++;
return data->str;
}
metacache_hash_t *bucket = &hash[h % HASH_SIZE];
if (!bucket->chain) {
n_buckets++;
}
size_t len = strlen (str);
data = malloc (sizeof (metacache_str_t) + len);
memset (data, 0, sizeof (metacache_str_t) + len);
data->refcount = 1;
memcpy (data->str, str, len+1);
data->next = bucket->chain;
bucket->chain = data;
n_strings++;
return data->str;
}
void
metacache_remove_string (const char *str) {
uint32_t h = metacache_get_hash_sdbm (str);
metacache_hash_t *bucket = &hash[h % HASH_SIZE];
metacache_str_t *chain = bucket->chain;
metacache_str_t *prev = NULL;
while (chain) {
if (!strcmp (chain->str, str)) {
chain->refcount--;
if (chain->refcount == 0) {
if (prev) {
prev->next = chain->next;
}
else {
bucket->chain = chain->next;
}
free (chain);
}
break;
}
prev = chain;
chain = chain->next;
}
}
void
metacache_remove_value (const char *value, size_t valuesize) {
uint32_t h = metacache_get_hash_sdbm (value, valuesize);
metacache_hash_t *bucket = &hash[h % HASH_SIZE];
metacache_str_t *chain = bucket->chain;
metacache_str_t *prev = NULL;
while (chain) {
if (chain->value_length == valuesize && !memcmp (chain->str, value, valuesize)) {
chain->refcount--;
if (chain->refcount == 0) {
if (prev) {
prev->next = chain->next;
}
else {
bucket->chain = chain->next;
}
free (chain);
}
break;
}
prev = chain;
chain = chain->next;
}
}