Fixing repeated needless sends

core/null.c

@@ -179,14 +179,14 @@ void ipfs_null_connection (void *ptr) {
 			retVal = libp2p_protocol_marshal(results, bytes_read, session, connection_param->local_node->protocol_handlers);
 			free(results);
 			if (retVal == -1) {
-				libp2p_logger_debug("null", "ipfs_null_marshal returned false\n");
+				libp2p_logger_debug("null", "protocol_marshal returned error.\n");
 				break;
 			} else if (retVal == 0) {
 				// clean up, but let someone else handle this from now on
-				libp2p_logger_debug("null", "ipfs_null_marshal returns 0. The daemon will no longer handle this.\n");
+				libp2p_logger_debug("null", "protocol_marshal returned 0. The daemon will no longer handle this.\n");
 				break;
 			} else {
-				libp2p_logger_debug("null", "ipfs_null_marshal returned 1. Looping again.");
+				libp2p_logger_debug("null", "protocol_marshal returned 1. Looping again.\n");
 			}
 		}
    	} else {

exchange/bitswap/engine.c

@@ -91,7 +91,7 @@ void* ipfs_bitswap_engine_peer_request_processor_start(void* ctx) {
 					libp2p_logger_debug("bitswap_engine", "We thought we were connected, but Peek reported an error.\n");
 					libp2p_peer_handle_connection_error(current_peer_entry);
 				} else if (retVal > 0) {
-					libp2p_logger_debug("bitswap_engine", "Something waiting on network for peer %s.\n", current_peer_entry->id);
+					libp2p_logger_debug("bitswap_engine", "%d bytes waiting on network for peer %s.\n", retVal, current_peer_entry->id);
 					unsigned char* buffer = NULL;
 					size_t buffer_len = 0;
 					if (current_peer_entry->sessionContext->default_stream->read(current_peer_entry->sessionContext, &buffer, &buffer_len, 1)) {
@@ -100,9 +100,13 @@ void* ipfs_bitswap_engine_peer_request_processor_start(void* ctx) {
 						free(buffer);
 						did_some_processing = 1;
 						if (retVal == -1) {
+							libp2p_logger_error("bitswap_engine", "protocol_marshal tried to handle the network traffic, but failed.\n");
 							// there was a problem. Clean up
 							libp2p_peer_handle_connection_error(current_peer_entry);
 						}
+					} else {
+						libp2p_logger_error("bitswap_engine", "It was said that there was %d bytes to read, but there wasn't. Cleaning up connection.\n");
+						libp2p_peer_handle_connection_error(current_peer_entry);
 					}
 				}
 			}

exchange/bitswap/message.c

@@ -657,7 +657,11 @@ int ipfs_bitswap_message_add_wantlist_items(struct BitswapMessage* message, stru
 			return 0;
 	}
 	for(int i = 0; i < cids->total; i++) {
-		const struct CidEntry* cidEntry = (const struct CidEntry*)libp2p_utils_vector_get(cids, i);
+		struct CidEntry* cidEntry = (struct CidEntry*)libp2p_utils_vector_get(cids, i);
+		if (cidEntry->cancel && cidEntry->cancel_has_been_sent)
+			continue;
+		if (!cidEntry->cancel && cidEntry->request_has_been_sent)
+			continue;
 		struct WantlistEntry* entry = ipfs_bitswap_wantlist_entry_new();
 		entry->block_size = ipfs_cid_protobuf_encode_size(cidEntry->cid);
 		entry->block = (unsigned char*) malloc(entry->block_size);
@@ -668,6 +672,10 @@ int ipfs_bitswap_message_add_wantlist_items(struct BitswapMessage* message, stru
 		entry->cancel = cidEntry->cancel;
 		entry->priority = 1;
 		libp2p_utils_vector_add(message->wantlist->entries, entry);
+		if (cidEntry->cancel)
+			cidEntry->cancel_has_been_sent = 1;
+		else
+			cidEntry->request_has_been_sent = 1;
 	}
 	return 1;
 }

exchange/bitswap/peer_request_queue.c

@@ -20,6 +20,8 @@ struct CidEntry* ipfs_bitswap_peer_request_cid_entry_new() {
 	if (entry != NULL) {
 		entry->cid = NULL;
 		entry->cancel = 0;
+		entry->cancel_has_been_sent = 0;
+		entry->request_has_been_sent = 0;
 	}
 	return entry;
 }
@@ -337,6 +339,26 @@ int ipfs_bitswap_peer_request_get_blocks_they_want(const struct BitswapContext*
 	return 0;
 }
 
+/***
+ * Determine if we have anything we want (that we haven't sent already)
+ * @param cid_entries the list of CidEntries that are in our queue to be sent
+ * @returns true(1) if we have something to send, false(0) otherwise
+ */
+int ipfs_bitswap_peer_request_we_want_cids(struct Libp2pVector* cid_entries) {
+	if (cid_entries == NULL)
+		return 0;
+	if (cid_entries->total == 0)
+		return 0;
+	for(int i = 0; i < cid_entries->total; i++) {
+		const struct CidEntry* entry = (const struct CidEntry*) libp2p_utils_vector_get(cid_entries, i);
+		if (entry->cancel && !entry->cancel_has_been_sent)
+			return 1;
+		if (!entry->cancel && !entry->request_has_been_sent)
+			return 1;
+	}
+	return 0;
+}
+
 /****
  * Handle a PeerRequest
  * @param context the BitswapContext
@@ -356,7 +378,7 @@ int ipfs_bitswap_peer_request_process_entry(const struct BitswapContext* context
 	}
 	// determine if we're connected
 	int connected = request->peer->is_local || request->peer->connection_type == CONNECTION_TYPE_CONNECTED;
-	int need_to_connect = request->cids_we_want->total != 0 || ipfs_bitswap_peer_request_cids_waiting(request->cids_they_want) || request->blocks_we_want_to_send->total != 0;
+	int need_to_connect = ipfs_bitswap_peer_request_we_want_cids(request->cids_we_want) || ipfs_bitswap_peer_request_cids_waiting(request->cids_they_want) || request->blocks_we_want_to_send->total != 0;
 
 	// determine if we need to connect
 	if (need_to_connect) {

include/ipfs/exchange/bitswap/peer_request_queue.h

@@ -12,6 +12,8 @@
 struct CidEntry {
 	struct Cid* cid;
 	int cancel;
+	int cancel_has_been_sent;
+	int request_has_been_sent;
 };
 
 struct PeerRequest {