propose mutex rework

server/channelserver/handlers_clients.go

@@ -10,15 +10,14 @@ import (
 func handleMsgSysEnumerateClient(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgSysEnumerateClient)
 
-	s.server.stagesLock.RLock()
+	s.server.RLock()
 	stage, ok := s.server.stages[pkt.StageID]
+	s.server.RUnlock()
 	if !ok {
-		s.server.stagesLock.RUnlock()
 		s.logger.Warn("Can't enumerate clients for stage that doesn't exist!", zap.String("stageID", pkt.StageID))
 		doAckSimpleFail(s, pkt.AckHandle, make([]byte, 4))
 		return
 	}
-	s.server.stagesLock.RUnlock()
 
 	// Read-lock the stage and make the response with all of the charID's in the stage.
 	resp := byteframe.NewByteFrame()
@@ -49,7 +48,6 @@ func handleMsgSysEnumerateClient(s *Session, p mhfpacket.MHFPacket) {
 	stage.RUnlock()
 
 	doAckBufSucceed(s, pkt.AckHandle, resp.Data())
-	s.logger.Debug("MsgSysEnumerateClient Done!")
 }
 
 func handleMsgMhfListMember(s *Session, p mhfpacket.MHFPacket) {

server/channelserver/handlers_stage.go

@@ -181,6 +181,7 @@ func handleMsgSysBackStage(s *Session, p mhfpacket.MHFPacket) {
 		panic(err)
 	}
 
+	s.stage.Lock()
 	if _, exists := s.stage.reservedClientSlots[s.charID]; exists {
 		delete(s.stage.reservedClientSlots, s.charID)
 	}
@@ -188,6 +189,7 @@ func handleMsgSysBackStage(s *Session, p mhfpacket.MHFPacket) {
 	if _, exists := s.server.stages[backStage].reservedClientSlots[s.charID]; exists {
 		delete(s.server.stages[backStage].reservedClientSlots, s.charID)
 	}
+	s.stage.Unlock()
 
 	doStageTransfer(s, pkt.AckHandle, backStage)
 }
@@ -279,9 +281,9 @@ func handleMsgSysUnreserveStage(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgSysSetStagePass(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgSysSetStagePass)
-	s.Lock()
+	s.RLock()
 	stage := s.reservationStage
-	s.Unlock()
+	s.RUnlock()
 	if stage != nil {
 		stage.Lock()
 		// Will only exist if host.
@@ -291,9 +293,9 @@ func handleMsgSysSetStagePass(s *Session, p mhfpacket.MHFPacket) {
 		stage.Unlock()
 	} else {
 		// Store for use on next ReserveStage.
-		s.Lock()
+		s.RLock()
 		s.stagePass = pkt.Password
-		s.Unlock()
+		s.RUnlock()
 	}
 }
 
@@ -311,7 +313,7 @@ func handleMsgSysSetStageBinary(s *Session, p mhfpacket.MHFPacket) {
 func handleMsgSysGetStageBinary(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgSysGetStageBinary)
 	if stage, exists := s.server.stages[pkt.StageID]; exists {
-		stage.Lock()
+		stage.RLock()
 		if binaryData, exists := stage.rawBinaryData[stageBinaryKey{pkt.BinaryType0, pkt.BinaryType1}]; exists {
 			doAckBufSucceed(s, pkt.AckHandle, binaryData)
 		} else if pkt.BinaryType1 == 4 {
@@ -323,7 +325,7 @@ func handleMsgSysGetStageBinary(s *Session, p mhfpacket.MHFPacket) {
 			s.logger.Warn("Sending blank stage binary")
 			doAckBufSucceed(s, pkt.AckHandle, []byte{})
 		}
-		stage.Unlock()
+		stage.RUnlock()
 	} else {
 		s.logger.Warn("Failed to get stage", zap.String("StageID", pkt.StageID))
 	}
@@ -340,9 +342,9 @@ func handleMsgSysWaitStageBinary(s *Session, p mhfpacket.MHFPacket) {
 		}
 		for {
 			s.logger.Debug("MsgSysWaitStageBinary before lock and get stage")
-			stage.Lock()
+			stage.RLock()
 			stageBinary, gotBinary := stage.rawBinaryData[stageBinaryKey{pkt.BinaryType0, pkt.BinaryType1}]
-			stage.Unlock()
+			stage.RUnlock()
 			s.logger.Debug("MsgSysWaitStageBinary after lock and get stage")
 			if gotBinary {
 				doAckBufSucceed(s, pkt.AckHandle, stageBinary)
@@ -362,29 +364,27 @@ func handleMsgSysWaitStageBinary(s *Session, p mhfpacket.MHFPacket) {
 func handleMsgSysEnumerateStage(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgSysEnumerateStage)
 
-	// Read-lock the server stage map.
-	s.server.stagesLock.RLock()
-	defer s.server.stagesLock.RUnlock()
-
-	// Build the response
 	bf := byteframe.NewByteFrame()
-	var joinable uint16
-	bf.WriteUint16(0)
-	for sid, stage := range s.server.stages {
+	var stages []*Stage
+	s.server.RLock()
+	for _, stage := range s.server.stages {
 		stage.RLock()
-
+		defer stage.RUnlock()
 		if len(stage.reservedClientSlots) == 0 && len(stage.clients) == 0 {
-			stage.RUnlock()
 			continue
 		}
 		if !strings.Contains(stage.id, pkt.StagePrefix) {
-			stage.RUnlock()
 			continue
 		}
-		joinable++
+		stages = append(stages, stage)
+	}
+	s.server.RUnlock()
 
+	bf.WriteUint16(uint16(len(stages)))
+	for _, stage := range stages {
+		stage.RLock()
 		bf.WriteUint16(uint16(len(stage.reservedClientSlots)))
-		bf.WriteUint16(0) // Unk
+		bf.WriteUint16(0)
 		if len(stage.clients) > 0 {
 			bf.WriteUint16(1)
 		} else {
@@ -393,16 +393,14 @@ func handleMsgSysEnumerateStage(s *Session, p mhfpacket.MHFPacket) {
 		bf.WriteUint16(stage.maxPlayers)
 		if len(stage.password) > 0 {
 			// This byte has also been seen as 1
-			// The quest is also recognised as locked when this is 2
+			// 2/3 = Locked, bitfield?
 			bf.WriteUint8(2)
 		} else {
 			bf.WriteUint8(0)
 		}
-		ps.Uint8(bf, sid, false)
+		ps.Uint8(bf, stage.id, false)
 		stage.RUnlock()
 	}
-	bf.Seek(0, 0)
-	bf.WriteUint16(joinable)
 
 	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
 }

server/channelserver/sys_channel_server.go

@@ -36,7 +36,7 @@ type userBinaryPartID struct {
 
 // Server is a MHF channel server.
 type Server struct {
-	sync.Mutex
+	sync.RWMutex
 	Channels       []*Server
 	ID             uint16
 	GlobalID       string
@@ -52,8 +52,7 @@ type Server struct {
 	listener       net.Listener // Listener that is created when Server.Start is called.
 	isShuttingDown bool
 
-	stagesLock sync.RWMutex
-	stages     map[string]*Stage
+	stages map[string]*Stage
 
 	// Used to map different languages
 	dict map[string]string
@@ -374,8 +373,6 @@ func (s *Server) FindSessionByCharID(charID uint32) *Session {
 }
 
 func (s *Server) FindObjectByChar(charID uint32) *Object {
-	s.stagesLock.RLock()
-	defer s.stagesLock.RUnlock()
 	for _, stage := range s.stages {
 		stage.RLock()
 		for objId := range stage.objects {

server/channelserver/sys_session.go

@@ -25,7 +25,7 @@ type packet struct {
 
 // Session holds state for the channel server connection.
 type Session struct {
-	sync.Mutex
+	sync.RWMutex
 	logger        *zap.Logger
 	server        *Server
 	rawConn       net.Conn