From 02afc8b64055d1d361e1c9a6384a308617bf8144 Mon Sep 17 00:00:00 2001
From: Alden Torres <aldenml@gmail.com>
Date: Wed, 12 Aug 2015 20:55:07 -0400
Subject: [PATCH] Added utp-stats bjam option to enable utp stream log (utp.log
 file).

---
 Jamfile                           |  3 +++
 include/libtorrent/utp_stream.hpp |  5 +++++
 src/utp_stream.cpp                | 32 +++++++++++++++++++++++++++----
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/Jamfile b/Jamfile
index 1dbd74330..ee1a7f276 100644
--- a/Jamfile
+++ b/Jamfile
@@ -472,6 +472,9 @@ feature.compose <invariant-checks>full : <define>TORRENT_EXPENSIVE_INVARIANT_CHE
 feature disk-stats : off on : composite propagated link-incompatible ;
 feature.compose <disk-stats>on : <define>TORRENT_DISK_STATS ;
 
+feature utp-stats : off on : composite propagated link-incompatible ;
+feature.compose <utp-stats>on : <define>TORRENT_UTP_LOG <define>TORRENT_VERBOSE_UTP_LOG ;
+
 feature simulate-slow-read : off on : composite propagated ;
 feature.compose <simulate-slow-read>on : <define>TORRENT_SIMULATE_SLOW_READ ;
 
diff --git a/include/libtorrent/utp_stream.hpp b/include/libtorrent/utp_stream.hpp
index fd4a4cb3d..f9473af71 100644
--- a/include/libtorrent/utp_stream.hpp
+++ b/include/libtorrent/utp_stream.hpp
@@ -468,6 +468,11 @@ public:
 		issue_write();
 	}
 
+#ifdef TORRENT_UTP_LOG
+	static bool utp_stream_log();
+	static void utp_stream_log(bool enable);
+#endif
+
 private:
 	// explicitly disallow assignment, to silence msvc warning
 	utp_stream& operator=(utp_stream const&);
diff --git a/src/utp_stream.cpp b/src/utp_stream.cpp
index fcc4aea4f..f5b444a39 100644
--- a/src/utp_stream.cpp
+++ b/src/utp_stream.cpp
@@ -44,9 +44,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <boost/cstdint.hpp>
 #include <limits>
 
-#define TORRENT_UTP_LOG 0
-#define TORRENT_VERBOSE_UTP_LOG 0
-
 // the behavior of the sequence numbers as implemented by uTorrent is not
 // particularly regular. This switch indicates the odd parts.
 #define TORRENT_UT_SEQ 1
@@ -70,7 +67,7 @@ static struct utp_logger
 
 	utp_logger() : utp_log_file(0)
 	{
-		utp_log_file = fopen("utp.log", "w+");
+		utp_log_file = NULL;
 	}
 	~utp_logger()
 	{
@@ -80,6 +77,8 @@ static struct utp_logger
 
 void utp_log(char const* fmt, ...)
 {
+	if (log_file_holder.utp_log_file == NULL) return;
+
 	mutex::scoped_lock lock(log_file_holder.utp_log_mutex);
 	static time_point start = clock_type::now();
 	fprintf(log_file_holder.utp_log_file, "[%012" PRId64 "] ", total_microseconds(clock_type::now() - start));
@@ -1172,6 +1171,31 @@ void utp_stream::do_connect(tcp::endpoint const& ep)
 	m_impl->send_syn();
 }
 
+#ifdef TORRENT_UTP_LOG
+	bool utp_stream::utp_stream_log() {
+		return log_file_holder.utp_log_file != NULL;
+	}
+
+	void utp_stream::utp_stream_log(bool enable) {
+		if (enable)
+		{
+			if (log_file_holder.utp_log_file == NULL)
+			{
+				log_file_holder.utp_log_file = fopen("utp.log", "w+");
+			}
+		}
+		else
+		{
+			if (log_file_holder.utp_log_file != NULL)
+			{
+				FILE* f = log_file_holder.utp_log_file;
+				log_file_holder.utp_log_file = NULL;
+				fclose(f);
+			}
+		}
+	}
+#endif
+
 // =========== utp_socket_impl ============
 
 utp_socket_impl::~utp_socket_impl()