face: congestion detection in TCP, UDP, and Unix socket transports
refs #4362
Change-Id: Idaa5d65e1f33663d95bad56de42640183b2cda6d
diff --git a/daemon/face/tcp-transport.cpp b/daemon/face/tcp-transport.cpp
index c14cab2..c95f693 100644
--- a/daemon/face/tcp-transport.cpp
+++ b/daemon/face/tcp-transport.cpp
@@ -1,6 +1,6 @@
/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014-2017, Regents of the University of California,
+/*
+ * Copyright (c) 2014-2018, Regents of the University of California,
* Arizona Board of Regents,
* Colorado State University,
* University Pierre & Marie Curie, Sorbonne University,
@@ -25,6 +25,11 @@
#include "tcp-transport.hpp"
+#if defined(__linux__)
+#include <linux/sockios.h>
+#include <sys/ioctl.h>
+#endif
+
namespace nfd {
namespace face {
@@ -55,6 +60,28 @@
NFD_LOG_FACE_INFO("Creating transport");
}
+ssize_t
+TcpTransport::getSendQueueLength()
+{
+ int queueLength = getSendQueueBytes();
+
+ // We want to obtain the amount of "not sent" bytes instead of the amount of "not sent" + "not
+ // acked" bytes. On Linux, we use SIOCOUTQNSD for this reason. However, macOS does not provide an
+ // efficient mechanism to obtain this value (SO_NWRITE includes both "not sent" and "not acked").
+#if defined(__linux__)
+ int nsd;
+ if (ioctl(m_socket.native_handle(), SIOCOUTQNSD, &nsd) < 0) {
+ NFD_LOG_FACE_WARN("Failed to obtain send queue length from socket: " << std::strerror(errno));
+ }
+ else if (nsd > 0) {
+ NFD_LOG_FACE_TRACE("SIOCOUTQNSD=" << nsd);
+ queueLength += nsd;
+ }
+#endif
+
+ return queueLength;
+}
+
bool
TcpTransport::canChangePersistencyToImpl(ndn::nfd::FacePersistency newPersistency) const
{