common rng for random shuffle

libi2pd/Tunnel.cpp

@@ -52,7 +52,7 @@ namespace tunnel
 		// shuffle records
 		std::vector<int> recordIndicies;
 		for (int i = 0; i < numRecords; i++) recordIndicies.push_back(i);
-		std::shuffle (recordIndicies.begin(), recordIndicies.end(), std::mt19937(std::random_device()()));
+		std::shuffle (recordIndicies.begin(), recordIndicies.end(), m_Pool ? m_Pool->GetRng () : std::mt19937(std::random_device()()));
 
 		// create real records
 		uint8_t * records = msg->GetPayload () + 1;

libi2pd/TunnelPool.cpp

@@ -7,7 +7,6 @@
 */
 
 #include <algorithm>
-#include <random>
 #include "I2PEndian.h"
 #include "Crypto.h"
 #include "Tunnel.h"
@@ -45,7 +44,7 @@ namespace tunnel
 		m_NumInboundHops (numInboundHops), m_NumOutboundHops (numOutboundHops),
 		m_NumInboundTunnels (numInboundTunnels), m_NumOutboundTunnels (numOutboundTunnels),
 		m_InboundVariance (inboundVariance), m_OutboundVariance (outboundVariance),
-		m_IsActive (true), m_CustomPeerSelector(nullptr)
+		m_IsActive (true), m_CustomPeerSelector(nullptr), m_Rng(m_Rd())
 	{
 		if (m_NumInboundTunnels > TUNNEL_POOL_MAX_INBOUND_TUNNELS_QUANTITY)
 			m_NumInboundTunnels = TUNNEL_POOL_MAX_INBOUND_TUNNELS_QUANTITY;
@@ -361,22 +360,20 @@ namespace tunnel
 
 		// new tests
 		std::vector<std::pair<std::shared_ptr<OutboundTunnel>, std::shared_ptr<InboundTunnel> > > newTests;
-		std::random_device rd;
-		std::mt19937 rnd(rd());
 		std::vector<std::shared_ptr<OutboundTunnel> > outboundTunnels;
 		{
 			std::unique_lock<std::mutex> l(m_OutboundTunnelsMutex);
 			for (auto& it: m_OutboundTunnels)
 				outboundTunnels.push_back (it);
 		}
-		std::shuffle (outboundTunnels.begin(), outboundTunnels.end(), rnd);
+		std::shuffle (outboundTunnels.begin(), outboundTunnels.end(), m_Rng);
 		std::vector<std::shared_ptr<InboundTunnel> > inboundTunnels;
 		{
 			std::unique_lock<std::mutex> l(m_InboundTunnelsMutex);
 			for (auto& it: m_InboundTunnels)
 				inboundTunnels.push_back (it);
 		}
-		std::shuffle (inboundTunnels.begin(), inboundTunnels.end(), rnd);
+		std::shuffle (inboundTunnels.begin(), inboundTunnels.end(), m_Rng);
 		auto it1 = outboundTunnels.begin ();
 		auto it2 = inboundTunnels.begin ();
 		while (it1 != outboundTunnels.end () && it2 != inboundTunnels.end ())

libi2pd/TunnelPool.h

@@ -15,6 +15,7 @@
 #include <utility>
 #include <mutex>
 #include <memory>
+#include <random>
 #include "Identity.h"
 #include "LeaseSet.h"
 #include "RouterInfo.h"
@@ -115,6 +116,8 @@ namespace tunnel
 			std::shared_ptr<const i2p::data::RouterInfo> SelectNextHop (std::shared_ptr<const i2p::data::RouterInfo> prevHop, bool reverse, bool endpoint) const;
 			bool StandardSelectPeers(Path & path, int numHops, bool inbound, SelectHopFunc nextHop);
 
+			std::mt19937& GetRng () { return m_Rng; }
+			
 		private:
 
 			void TestTunnels ();
@@ -148,6 +151,9 @@ namespace tunnel
 			uint64_t m_MinLatency = 0; // if > 0 this tunnel pool will try building tunnels with minimum latency by ms
 			uint64_t m_MaxLatency = 0; // if > 0 this tunnel pool will try building tunnels with maximum latency by ms
 
+			std::random_device m_Rd;
+			std::mt19937 m_Rng;
+			
 		public:
 
 			// for HTTP only