use NULL as flag for evaluation of query, ensure we pass non-NULL for reply_block to evaluate reply even if reply is zero bytes long

1 files changed, 5 insertions, 0 deletions

diff --git a/src/dht/gnunet-service-dht_datacache.c b/src/dht/gnunet-service-dht_datacache.c
index 9b4dace67..74fa1cc29 100644
--- a/src/dht/gnunet-service-dht_datacache.c
+++ b/src/dht/gnunet-service-dht_datacache.c
@@ -170,9 +170,14 @@ datacache_get_iterator (void *cls,
                         unsigned int put_path_length,
                         const struct GNUNET_PeerIdentity *put_path)
 {
+  static char non_null;
   struct GetRequestContext *ctx = cls;
   enum GNUNET_BLOCK_EvaluationResult eval;
 
+  if ( (NULL == data) &&
+       (0 == data_size) )
+    data = &non_null; /* point anywhere, but not to NULL */
+
   eval
     = GNUNET_BLOCK_evaluate (GDS_block_context,
                              type,