#define DEBUG(...) \
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, __VA_ARGS__)
+/**
+ * How many "closest" results to we return for migration when
+ * asked (at most)?
+ */
+#define NUM_CLOSEST 42
+
/**
* Handle to the datacache service (for inserting/retrieving data)
*/
* @param key the query this reply is for
* @param put_path_length number of peers in @a put_path
* @param put_path path the reply took on put
+ * @param get_path_length number of peers in @a get_path
+ * @param get_path path the reply took on get
* @param type type of the reply
* @param data_size number of bytes in @a data
* @param data application payload data
const struct GNUNET_HashCode *key,
unsigned int put_path_length,
const struct GNUNET_PeerIdentity *put_path,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *get_path,
enum GNUNET_BLOCK_Type type,
size_t data_size,
const void *data)
{
int r;
+ struct GNUNET_PeerIdentity path[get_path_length + put_path_length];
if (NULL == datacache)
{
GNUNET_break (0);
return;
}
-
+ memcpy (path,
+ put_path,
+ put_path_length * sizeof (struct GNUNET_PeerIdentity));
+ memcpy (&path[put_path_length],
+ get_path,
+ get_path_length * sizeof (struct GNUNET_PeerIdentity));
/* Put size is actual data size plus struct overhead plus path length (if any) */
r = GNUNET_DATACACHE_put (datacache,
key,
data,
type,
expiration,
- put_path_length,
- put_path);
+ get_path_length + put_path_length,
+ path);
if (GNUNET_OK == r)
GNUNET_STATISTICS_update (GDS_stats,
gettext_noop ("# ITEMS stored in datacache"), 1,
GNUNET_h2s (key),
data_size,
r,
- put_path_length);
+ put_path_length + get_path_length);
}
-/**
- * List of peers in the get path.
- */
-struct GetPath
-{
- /**
- * Pointer to next item in the list
- */
- struct GetPath *next;
-
- /**
- * Pointer to previous item in the list
- */
- struct GetPath *prev;
-
- /**
- * An element in the get path.
- */
- struct GNUNET_PeerIdentity peer;
-};
-
-
/**
* Context containing information about a GET request.
*/
*/
struct GNUNET_HashCode key;
+ /**
+ * The trail this request was for
+ */
+ const struct GNUNET_HashCode *trail_id;
+
/**
* Number of bytes in @e xquery.
*/
*/
uint32_t reply_bf_mutator;
- /**
- * Total number of peers in @e head.
- */
- unsigned int get_path_length;
-
/**
* Return value to give back.
*/
enum GNUNET_BLOCK_EvaluationResult eval;
- /**
- * Peeer which has the data for the key.
- */
- struct GNUNET_PeerIdentity source_peer;
-
- /**
- * Next hop to forward the get result to.
- */
- struct GNUNET_PeerIdentity next_hop;
-
- /**
- * Head of get path.
- */
- struct GetPath *head;
-
- /**
- * Tail of get path.
- */
- struct GetPath *tail;
-
- /* get_path */
};
gettext_noop
("# Good RESULTS found in datacache"), 1,
GNUNET_NO);
- struct GNUNET_PeerIdentity *get_path;
- get_path = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) *
- ctx->get_path_length);
- struct GetPath *iterator;
- iterator = ctx->head;
- int i = 0;
- while (i < ctx->get_path_length)
- {
- get_path[i] = iterator->peer;
- i++;
- iterator = iterator->next;
- }
- GDS_NEIGHBOURS_send_get_result (key,type, &(ctx->next_hop),&(ctx->source_peer),
- put_path_length, put_path, ctx->get_path_length,
- get_path, exp, data, size );
- GNUNET_free_non_null (get_path);
-
+ GDS_NEIGHBOURS_send_get_result (ctx->trail_id,
+ key,
+ type,
+ put_path_length,
+ put_path,
+ exp,
+ data,
+ size);
break;
case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
GNUNET_STATISTICS_update (GDS_stats,
/**
* Handle a GET request we've received from another peer.
*
+ * @param trail_id trail identifying where to send the result to, NULL for us
* @param key the query
* @param type requested data type
* @param xquery extended query
* @param xquery_size number of bytes in @a xquery
* @param reply_bf where the reply bf is (to be) stored, possibly updated, can be NULL
* @param reply_bf_mutator mutation value for @a reply_bf
- * @param get_path_length Total number of peers in @a get_path
- * @param get_path Peers query has traversed during GET
* @return evaluation result for the local replies
*/
enum GNUNET_BLOCK_EvaluationResult
-GDS_DATACACHE_handle_get (const struct GNUNET_HashCode *key,
+GDS_DATACACHE_handle_get (const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_HashCode *key,
enum GNUNET_BLOCK_Type type,
const void *xquery,
size_t xquery_size,
struct GNUNET_CONTAINER_BloomFilter **reply_bf,
- uint32_t reply_bf_mutator,
- uint32_t get_path_length,
- struct GNUNET_PeerIdentity *get_path,
- struct GNUNET_PeerIdentity *next_hop,
- struct GNUNET_PeerIdentity *source_peer)
+ uint32_t reply_bf_mutator)
{
struct GetRequestContext ctx;
unsigned int r;
- if (datacache == NULL)
+ if (NULL == datacache)
return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
GNUNET_STATISTICS_update (GDS_stats,
gettext_noop ("# GET requests given to datacache"),
1, GNUNET_NO);
ctx.eval = GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
+ ctx.trail_id = trail_id;
ctx.key = *key;
ctx.xquery = xquery;
ctx.xquery_size = xquery_size;
ctx.reply_bf = reply_bf;
ctx.reply_bf_mutator = reply_bf_mutator;
- ctx.get_path_length = get_path_length;
-
- if (NULL != next_hop)
- ctx.next_hop = *next_hop;
- unsigned int i = 0;
-
- ctx.head = NULL;
- ctx.tail = NULL;
- if (NULL != get_path)
- {
- while (i < get_path_length)
- {
- struct GetPath *element;
- element = GNUNET_new (struct GetPath);
- element->next = NULL;
- element->prev = NULL;
- element->peer = get_path[i];
- GNUNET_CONTAINER_DLL_insert_tail (ctx.head, ctx.tail, element);
- i++;
- }
- }
-
r = GNUNET_DATACACHE_get (datacache,
key,
type,
}
+/**
+ * Function called with a random element from the datacache.
+ * Stores the key in the closure.
+ *
+ * @param cls a `struct GNUNET_HashCode *`, where to store the @a key
+ * @param key key for the content
+ * @param data_size number of bytes in @a data
+ * @param data content stored
+ * @param type type of the content
+ * @param exp when will the content expire?
+ * @param path_info_len number of entries in @a path_info
+ * @param path_info a path through the network
+ * @return #GNUNET_OK to continue iterating, #GNUNET_SYSERR to abort
+ */
+static int
+datacache_random_iterator (void *cls,
+ const struct GNUNET_HashCode *key,
+ size_t data_size,
+ const char *data,
+ enum GNUNET_BLOCK_Type type,
+ struct GNUNET_TIME_Absolute exp,
+ unsigned int path_info_len,
+ const struct GNUNET_PeerIdentity *path_info)
+{
+ struct GNUNET_HashCode *dest = cls;
+
+ *dest = *key;
+ return GNUNET_OK; /* should actually not matter which we return */
+}
+
+
+/**
+ * Obtain a random key from the datacache.
+ * Used by Whanau for load-balancing.
+ *
+ * @param[out] key where to store the key of a random element,
+ * randomized by PRNG if datacache is empty
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the datacache is empty
+ */
+int
+GDS_DATACACHE_get_random_key (struct GNUNET_HashCode *key)
+{
+ if (0 ==
+ GNUNET_DATACACHE_get_random (datacache,
+ &datacache_random_iterator,
+ key))
+ {
+ /* randomize key in this case */
+ GNUNET_CRYPTO_hash_create_random (GNUNET_CRYPTO_QUALITY_NONCE,
+ key);
+ return GNUNET_SYSERR;
+ }
+ return GNUNET_OK;
+}
+
+/**
+ * Iterator for local get request results,
+ *
+ * @param cls closure with the `struct GNUNET_HashCode *` with the trail ID
+ * @param key the key this data is stored under
+ * @param size the size of the data identified by key
+ * @param data the actual data
+ * @param type the type of the data
+ * @param exp when does this value expire?
+ * @param put_path_length number of peers in @a put_path
+ * @param put_path path the reply took on put
+ * @return #GNUNET_OK to continue iteration, anything else
+ * to stop iteration.
+ */
+static int
+datacache_get_successors_iterator (void *cls,
+ const struct GNUNET_HashCode *key,
+ size_t size,
+ const char *data,
+ enum GNUNET_BLOCK_Type type,
+ struct GNUNET_TIME_Absolute exp,
+ unsigned int put_path_length,
+ const struct GNUNET_PeerIdentity *put_path)
+{
+ const struct GNUNET_HashCode *trail_id = cls;
+
+ GDS_NEIGHBOURS_send_get_result (trail_id,
+ key,
+ type,
+ put_path_length, put_path,
+ exp,
+ data,
+ size);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Handle a request for data close to a key that we have received from
+ * another peer.
+ *
+ * @param trail_id trail where the reply needs to be send to
+ * @param key the location at which the peer is looking for data that is close
+ */
+void
+GDS_DATACACHE_get_successors (const struct GNUNET_HashCode *trail_id,
+ const struct GNUNET_HashCode *key)
+{
+ (void) GNUNET_DATACACHE_get_closest (datacache,
+ key,
+ NUM_CLOSEST,
+ &datacache_get_successors_iterator,
+ (void *) trail_id);
+}
+
+
/**
* Initialize datacache subsystem.
*/