added performance alert for address-in-use errors

docs/manual.rst

@@ -6969,7 +6969,8 @@ upload or download rate performance.
 			download_limit_too_low,
 			send_buffer_watermark_too_low,
 			too_many_optimistic_unchoke_slots,
-			too_high_disk_queue_limit
+			too_high_disk_queue_limit,
+			too_few_outgoing_ports
 		};
 
 		performance_warning_t warning_code;
@@ -7039,6 +7040,12 @@ too_high_disk_queue_limit
 	portions of the cache before allowing peers to download any more, onto the disk write
 	queue. Either lower ``max_queued_disk_bytes`` or increase ``cache_size``.
 
+too_few_outgoing_ports
+	This is generated if outgoing peer connections are failing because of *address in use*
+	errors, indicating that ``session_settings::outgoing_ports`` is set and is too small of
+	a range. Consider not using the ``outgoing_ports`` setting at all, or widen the range to
+	include more ports.
+
 state_changed_alert
 -------------------
 

include/libtorrent/alert_types.hpp

@@ -225,7 +225,7 @@ namespace libtorrent
 			too_many_optimistic_unchoke_slots,
 			bittyrant_with_no_uplimit,
 			too_high_disk_queue_limit,
-
+			too_few_outgoing_ports,
 
 
 			num_warnings

src/alert.cpp

@@ -119,7 +119,8 @@ namespace libtorrent {
 			"send buffer watermark too low (upload rate will suffer)",
 			"too many optimistic unchoke slots",
 			"using bittyrant unchoker with no upload rate limit set",
-			"the disk queue limit is too high compared to the cache size. The disk queue eats into the cache size"
+			"the disk queue limit is too high compared to the cache size. The disk queue eats into the cache size",
+			"too few ports allowed for outgoing connections"
 		};
 
 		return torrent_alert::message() + ": performance warning: "

src/peer_connection.cpp

@@ -3603,6 +3603,14 @@ namespace libtorrent
 		torrent_handle handle;
 		if (t) handle = t->get_handle();
 
+		if (ec == error::address_in_use
+			&& m_ses.m_settings.outgoing_ports.first != 0)
+		{
+			if (m_ses.m_alerts.should_post<performance_alert>())
+				m_ses.m_alerts.post_alert(performance_alert(
+					handle, performance_alert::too_few_outgoing_ports));
+		}
+
 		if (ec)
 		{
 			if ((error > 1 || ec.category() == socks_category)