coap_session, net.c: Add debug messages on TCP RX/TX.

include/coap/coap_session.h

@@ -198,8 +198,9 @@ coap_session_t *coap_new_server_session(
 );
 
 /**
-* Function interface for data transmission. This function returns the number of
-* bytes that have been transmitted, or a value less than zero on error.
+* Function interface for datagram data transmission. This function returns
+* the number of bytes that have been transmitted, or a value less than zero
+* on error.
 *
 * @param session          Session to send data on.
 * @param data             The data to send.
@@ -211,6 +212,22 @@ coap_session_t *coap_new_server_session(
 ssize_t coap_session_send(coap_session_t *session,
   const uint8_t *data, size_t datalen);
 
+/**
+* Function interface for stream data transmission. This function returns
+* the number of bytes that have been transmitted, or a value less than zero
+* on error. The number of bytes written may be less than datalen because of
+* congestion control.
+*
+* @param session          Session to send data on.
+* @param data             The data to send.
+* @param datalen          The actual length of @p data.
+*
+* @return                 The number of bytes written on success, or a value
+*                         less than zero on error.
+*/
+ssize_t coap_session_write(coap_session_t *session,
+  const uint8_t *data, size_t datalen);
+
 /**
 * Send a pdu according to the session's protocol. This function returns
 * the number of bytes that have been transmitted, or a value less than zero

src/coap_session.c

@@ -180,6 +180,17 @@ ssize_t coap_session_send(coap_session_t *session, const uint8_t *data, size_t d
   return bytes_written;
 }
 
+ssize_t coap_session_write(coap_session_t *session, const uint8_t *data, size_t datalen) {
+  ssize_t bytes_written = coap_socket_write(&session->sock, data, datalen);
+  if (bytes_written > 0) {
+    coap_ticks(&session->last_rx_tx);
+    debug("*  %s: sent %zd bytes\n", coap_session_str(session), datalen);
+  } else if (bytes_written < 0) {
+    debug( "*  %s: failed to send %zd bytes\n", coap_session_str(session), datalen );
+  }
+  return bytes_written;
+}
+
 ssize_t
 coap_session_delay_pdu(coap_session_t *session, coap_pdu_t *pdu,
                        coap_queue_t *node)

src/net.c

@@ -643,8 +643,8 @@ coap_session_send_pdu(coap_session_t *session, coap_pdu_t *pdu) {
 				     pdu->used_size + pdu->hdr_size);
       break;
     case COAP_PROTO_TCP:
-      bytes_written = coap_socket_write(&session->sock,
-	pdu->token - pdu->hdr_size, pdu->used_size + pdu->hdr_size);
+      bytes_written = coap_session_write(session, pdu->token - pdu->hdr_size,
+	                                 pdu->used_size + pdu->hdr_size);
       break;
     case COAP_PROTO_TLS:
       bytes_written = coap_tls_write(session, pdu->token - pdu->hdr_size,
@@ -1018,8 +1018,8 @@ coap_write_session(coap_context_t *ctx, coap_session_t *session, coap_tick_t now
     assert(session->partial_write < q->pdu->used_size + q->pdu->hdr_size);
     switch (session->proto) {
       case COAP_PROTO_TCP:
-	bytes_written = coap_socket_write(
-	  &session->sock,
+	bytes_written = coap_session_write(
+	  session,
 	  q->pdu->token - q->pdu->hdr_size - session->partial_write,
 	  q->pdu->used_size + q->pdu->hdr_size - session->partial_write
 	);
@@ -1088,6 +1088,10 @@ coap_read_session(coap_context_t *ctx, coap_session_t *session, coap_tick_t now)
 	bytes_read = coap_socket_read(&session->sock, buf, buf_len);
       else if (session->proto == COAP_PROTO_TLS)
 	bytes_read = coap_tls_read(session, buf, buf_len);
+      if (bytes_read > 0) {
+        debug("*  %s: received %zd bytes\n", coap_session_str(session), bytes_read);
+        session->last_rx_tx = now;
+      }
       p = buf;
       retry = bytes_read == buf_len;
       while (bytes_read > 0) {