/* if return item is not NULL, free by caller */
item *item_get(char *key, size_t nkey){
item *it = NULL;
DBT dbkey, dbdata;
bool stop;
int ret;
/* first, alloc a fixed size */
it = item_alloc2(settings.item_buf_size);
if (it == 0) {
return NULL;
}
BDB_CLEANUP_DBT();
dbkey.data = key;
dbkey.size = nkey;
dbdata.ulen = settings.item_buf_size;
dbdata.data = it;
dbdata.flags = DB_DBT_USERMEM;
stop = false;
/* try to get a item from bdb */
while (!stop) {
switch (ret = dbp->get(dbp, NULL, &dbkey, &dbdata, 0)) {
case DB_BUFFER_SMALL: /* user mem small */
/* free the original smaller buffer */
item_free(it);
/* alloc the correct size */
it = item_alloc2(dbdata.size);
if (it == NULL) {
return NULL;
}
dbdata.ulen = dbdata.size;
dbdata.data = it;
break;
case 0: /* Success. */
stop = true;
break;
case DB_NOTFOUND:
stop = true;
item_free(it);
it = NULL;
break;
default:
/* TODO: may cause bug here, if return DB_BUFFER_SMALL then retun non-zero again
* here 'it' may not a full one. a item buffer larger than item_buf_size may be added to freelist */
stop = true;
item_free(it);
it = NULL;
if (settings.verbose > 1) {
fprintf(stderr, "dbp->get: %s\n", db_strerror(ret));
}
}
}
return it;
}
/* if return item is not NULL, free by caller */
item *bdb_get(char *key){
pthread_rwlock_rdlock(&qlist_ht_lock);
item *it = NULL;
DB_TXN *txnp = NULL;
int ret;
queue_t *q = (queue_t *)hashtable_search(qlist_htp, (void *)key);
/* queue not exsited */
if (q == NULL) {
pthread_rwlock_unlock(&qlist_ht_lock);
return NULL;
} else {
DBT dbkey, dbdata;
db_recno_t recno;
/* first, alloc a fixed size */
it = item_alloc2();
if (it == 0) {
pthread_rwlock_unlock(&qlist_ht_lock);
return NULL;
}
BDB_CLEANUP_DBT();
dbkey.data = &recno;
dbkey.ulen = sizeof(recno);
dbkey.flags = DB_DBT_USERMEM;
dbdata.ulen = bdb_settings.re_len;
dbdata.data = it;
dbdata.flags = DB_DBT_USERMEM;
ret = envp->txn_begin(envp, NULL, &txnp, 0);
CHECK_DB_RET(ret);
ret = q->dbp->get(q->dbp, txnp, &dbkey, &dbdata, DB_CONSUME);
CHECK_DB_RET(ret);
ret = txnp->commit(txnp, 0);
CHECK_DB_RET(ret);
pthread_mutex_lock(&(q->lock));
(q->get_hits)++;
pthread_mutex_unlock(&(q->lock));
}
pthread_rwlock_unlock(&qlist_ht_lock);
return it;
dberr:
item_free(it);
it = NULL;
if (txnp != NULL){
txnp->abort(txnp);
}
if (settings.verbose > 1) {
fprintf(stderr, "bdb_get: %s\n", db_strerror(ret));
}
pthread_rwlock_unlock(&qlist_ht_lock);
return NULL;
}
