ggpo: make chat thread-safe. Deadlock on early rollback

Make ggpo_send_message() thread-safe
Deadlock UI/emu threads if rollback happens before first render
Disable rollback wait in single-thread mode

core/deps/ggpo/lib/ggpo/network/udp_proto.cpp

@@ -286,14 +286,17 @@ UdpProtocol::SendMsg(UdpMsg *msg)
 {
    LogMsg("send", msg);
 
-   _packets_sent++;
-   _last_send_time = Platform::GetCurrentTimeMS();
-   _bytes_sent += msg->PacketSize();
+   {
+	   std::lock_guard<std::mutex> lock(_send_mutex);
+	   _packets_sent++;
+	   _last_send_time = Platform::GetCurrentTimeMS();
+	   _bytes_sent += msg->PacketSize();
 
-   msg->hdr.magic = _magic_number;
-   msg->hdr.sequence_number = _next_send_seq++;
+	   msg->hdr.magic = _magic_number;
+	   msg->hdr.sequence_number = _next_send_seq++;
 
-   _send_queue.push(QueueEntry(Platform::GetCurrentTimeMS(), _peer_addr, msg));
+	   _send_queue.push(QueueEntry(Platform::GetCurrentTimeMS(), _peer_addr, msg));
+   }
    PumpSendQueue();
 }
 
@@ -753,6 +756,7 @@ UdpProtocol::SetDisconnectNotifyStart(int timeout)
 void
 UdpProtocol::PumpSendQueue()
 {
+   std::lock_guard<std::mutex> lock(_send_mutex);
    while (!_send_queue.empty()) {
       QueueEntry &entry = _send_queue.front();
 
@@ -793,6 +797,7 @@ UdpProtocol::PumpSendQueue()
 void
 UdpProtocol::ClearSendQueue()
 {
+   std::lock_guard<std::mutex> lock(_send_mutex);
    while (!_send_queue.empty()) {
       delete _send_queue.front().msg;
       _send_queue.pop();

core/deps/ggpo/lib/ggpo/network/udp_proto.h

@@ -16,6 +16,7 @@
 #include "ggponet.h"
 #include "ring_buffer.h"
 #include <vector>
+#include <mutex>
 
 class UdpProtocol : public IPollSink
 {
@@ -153,6 +154,7 @@ protected:
       UdpMsg*     msg;
    }              _oo_packet;
    RingBuffer<QueueEntry, 64> _send_queue;
+   std::mutex     _send_mutex;
 
    std::vector<uint8> verification;
 

core/hw/pvr/Renderer_if.cpp

@@ -466,7 +466,8 @@ void rend_allow_rollback()
 
 void rend_start_rollback()
 {
-	vramRollback.Wait();
+	if (config::ThreadedRendering)
+		vramRollback.Wait();
 }
 
 void rend_serialize(void **data, unsigned int *total_size)

core/network/ggpo.cpp

@@ -159,6 +159,7 @@ struct Inputs
 		u8 keys[6];
 	} u;
 };
+static_assert(sizeof(Inputs) == 10, "wrong Inputs size");
 
 struct GameEvent
 {
@@ -183,6 +184,7 @@ struct GameEvent
 static bool begin_game(const char *)
 {
 	DEBUG_LOG(NETWORK, "Game begin");
+	rend_allow_rollback();
 	return true;
 }