Allow the number of incoming connections to be limited

It was already possible to limit outgoing connections. One might want
to do this on home network connections with high bandwidth but low
usage caps.

1 files changed, 45 insertions, 33 deletions

diff --git a/contrib/epee/include/net/levin_protocol_handler_async.h b/contrib/epee/include/net/levin_protocol_handler_async.h
index ee64da5d8..de270bfd0 100644
--- a/contrib/epee/include/net/levin_protocol_handler_async.h
+++ b/contrib/epee/include/net/levin_protocol_handler_async.h
@@ -77,6 +77,8 @@ class async_protocol_handler_config
   levin_commands_handler<t_connection_context>* m_pcommands_handler;
   void (*m_pcommands_handler_destroy)(levin_commands_handler<t_connection_context>*);
 
+  void delete_connections (size_t count, bool incoming);
+
 public:
   typedef t_connection_context connection_context;
   uint64_t m_max_packet_size; 
@@ -101,6 +103,7 @@ public:
   {}
   ~async_protocol_handler_config() { set_handler(NULL, NULL); }
   void del_out_connections(size_t count);
+  void del_in_connections(size_t count);
 };
 
 
@@ -731,41 +734,50 @@ void async_protocol_handler_config<t_connection_context>::del_connection(async_p
 }
 //------------------------------------------------------------------------------------------
 template<class t_connection_context>
+void async_protocol_handler_config<t_connection_context>::delete_connections(size_t count, bool incoming)
+{
+  std::vector <boost::uuids::uuid> connections;
+  CRITICAL_REGION_BEGIN(m_connects_lock);
+  for (auto& c: m_connects)
+  {
+    if (c.second->m_connection_context.m_is_income == incoming)
+      connections.push_back(c.first);
+  }
+
+  // close random connections from  the provided set
+  // TODO or better just keep removing random elements (performance)
+  unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
+  shuffle(connections.begin(), connections.end(), std::default_random_engine(seed));
+  while (count > 0 && connections.size() > 0)
+  {
+    try
+    {
+      auto i = connections.end() - 1;
+      async_protocol_handler<t_connection_context> *conn = m_connects.at(*i);
+      del_connection(conn);
+      close(*i);
+      connections.erase(i);
+    }
+    catch (const std::out_of_range &e)
+    {
+      MWARNING("Connection not found in m_connects, continuing");
+    }
+    --count;
+  }
+
+  CRITICAL_REGION_END();
+}
+//------------------------------------------------------------------------------------------
+template<class t_connection_context>
 void async_protocol_handler_config<t_connection_context>::del_out_connections(size_t count)
 {
-	std::vector <boost::uuids::uuid> out_connections;
-	CRITICAL_REGION_BEGIN(m_connects_lock);
-	for (auto& c: m_connects)
-	{
-		if (!c.second->m_connection_context.m_is_income)
-			out_connections.push_back(c.first);
-	}
-	
-	if (out_connections.size() == 0)
-		return;
-
-	// close random out connections
-	// TODO or better just keep removing random elements (performance)
-	unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
-	shuffle(out_connections.begin(), out_connections.end(), std::default_random_engine(seed));
-	while (count > 0 && out_connections.size() > 0)
-	{
-		try
-		{
-			auto i = out_connections.end() - 1;
-			async_protocol_handler<t_connection_context> *conn = m_connects.at(*i);
-			del_connection(conn);
-			close(*i);
-			out_connections.erase(i);
-		}
-		catch (const std::out_of_range &e)
-		{
-			MWARNING("Connection not found in m_connects, continuing");
-		}
-		--count;
-	}
-	
-	CRITICAL_REGION_END();
+  delete_connections(count, false);
+}
+//------------------------------------------------------------------------------------------
+template<class t_connection_context>
+void async_protocol_handler_config<t_connection_context>::del_in_connections(size_t count)
+{
+  delete_connections(count, true);
 }
 //------------------------------------------------------------------------------------------
 template<class t_connection_context>