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lib/connections, vendor: Change KCP mux to SMUX

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Closes #4032
This commit is contained in:
Audrius Butkevicius
2017-03-09 14:01:07 +01:00
committed by Jakob Borg
parent f35e1ac0c5
commit ceea5ebeb3
22 changed files with 908 additions and 1889 deletions
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140
vendor/github.com/xtaci/kcp-go/sess.go generated vendored
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@@ -23,13 +23,23 @@ func (errTimeout) Temporary() bool { return true }
func (errTimeout) Error() string { return "i/o timeout" }
const (
defaultWndSize = 128 // default window size, in packet
nonceSize = 16 // magic number
crcSize = 4 // 4bytes packet checksum
// 16-bytes magic number for each packet
nonceSize = 16
// 4-bytes packet checksum
crcSize = 4
// overall crypto header size
cryptHeaderSize = nonceSize + crcSize
mtuLimit = 2048
rxQueueLimit = 8192
rxFECMulti = 3 // FEC keeps rxFECMulti* (dataShard+parityShard) ordered packets in memory
// maximum packet size
mtuLimit = 2048
// packet receiving channel limit
rxQueueLimit = 2048
// FEC keeps rxFECMulti* (dataShard+parityShard) ordered packets in memory
rxFECMulti = 3
)
const (
@@ -38,8 +48,12 @@ const (
)
var (
// global packet buffer
// shared among sending/receiving/FEC
xmitBuf sync.Pool
sid uint32
// monotonic session id
sid uint32
)
func init() {
@@ -51,36 +65,39 @@ func init() {
type (
// UDPSession defines a KCP session implemented by UDP
UDPSession struct {
// core
sid uint32
conn net.PacketConn // the underlying packet socket
kcp *KCP // the core ARQ
l *Listener // point to server listener if it's a server socket
block BlockCrypt // encryption
sockbuff []byte // kcp receiving is based on packet, I turn it into stream
sid uint32 // session id(monotonic)
conn net.PacketConn // the underlying packet connection
kcp *KCP // KCP ARQ protocol
l *Listener // point to the Listener if it's accepted by Listener
block BlockCrypt // block encryption
// forward error correction
fec *FEC
fecDataShards [][]byte
fecHeaderOffset int
fecPayloadOffset int
fecCnt int // count datashard
fecMaxSize int // record maximum data length in datashard
// kcp receiving is based on packets
// sockbuff turns packets into stream
sockbuff []byte
fec *FEC // forward error correction
fecDataShards [][]byte // data shards cache
fecShardCount int // count the number of datashards collected
fecMaxSize int // record maximum data length in datashard
fecHeaderOffset int // FEC header offset in packet
fecPayloadOffset int // FEC payload offset in packet
// settings
remote net.Addr
remote net.Addr // remote peer address
rd time.Time // read deadline
wd time.Time // write deadline
headerSize int
updateInterval int32
ackNoDelay bool
headerSize int // the overall header size added before KCP frame
updateInterval int32 // interval in seconds to call kcp.flush()
ackNoDelay bool // send ack immediately for each incoming packet
// notifications
die chan struct{}
chReadEvent chan struct{}
chWriteEvent chan struct{}
isClosed bool
mu sync.Mutex
die chan struct{} // notify session has Closed
chReadEvent chan struct{} // notify Read() can be called without blocking
chWriteEvent chan struct{} // notify Write() can be called without blocking
isClosed bool // flag the session has Closed
mu sync.Mutex
}
setReadBuffer interface {
@@ -132,7 +149,6 @@ func newUDPSession(conv uint32, dataShards, parityShards int, l *Listener, conn
sess.output(buf[:size])
}
})
sess.kcp.WndSize(defaultWndSize, defaultWndSize)
sess.kcp.SetMtu(IKCP_MTU_DEF - sess.headerSize)
sess.kcp.setFEC(dataShards, parityShards)
@@ -324,11 +340,16 @@ func (s *UDPSession) SetWindowSize(sndwnd, rcvwnd int) {
s.kcp.WndSize(sndwnd, rcvwnd)
}
// SetMtu sets the maximum transmission unit
func (s *UDPSession) SetMtu(mtu int) {
// SetMtu sets the maximum transmission unit(not including UDP header)
func (s *UDPSession) SetMtu(mtu int) bool {
if mtu > mtuLimit {
return false
}
s.mu.Lock()
defer s.mu.Unlock()
s.kcp.SetMtu(mtu - s.headerSize)
return true
}
// SetStreamMode toggles the stream mode on/off
@@ -416,9 +437,9 @@ func (s *UDPSession) output(buf []byte) {
// copy data to fec datashards
sz := len(ext)
s.fecDataShards[s.fecCnt] = s.fecDataShards[s.fecCnt][:sz]
copy(s.fecDataShards[s.fecCnt], ext)
s.fecCnt++
s.fecDataShards[s.fecShardCount] = s.fecDataShards[s.fecShardCount][:sz]
copy(s.fecDataShards[s.fecShardCount], ext)
s.fecShardCount++
// record max datashard length
if sz > s.fecMaxSize {
@@ -426,7 +447,7 @@ func (s *UDPSession) output(buf []byte) {
}
// calculate Reed-Solomon Erasure Code
if s.fecCnt == s.fec.dataShards {
if s.fecShardCount == s.fec.dataShards {
// bzero each datashard's tail
for i := 0; i < s.fec.dataShards; i++ {
shard := s.fecDataShards[i]
@@ -442,7 +463,7 @@ func (s *UDPSession) output(buf []byte) {
}
// reset counters to zero
s.fecCnt = 0
s.fecShardCount = 0
s.fecMaxSize = 0
}
}
@@ -557,7 +578,7 @@ func (s *UDPSession) kcpInput(data []byte) {
s.mu.Unlock()
}
atomic.AddUint64(&DefaultSnmp.InSegs, 1)
atomic.AddUint64(&DefaultSnmp.InPkts, 1)
atomic.AddUint64(&DefaultSnmp.InBytes, uint64(len(data)))
if fecParityShards > 0 {
atomic.AddUint64(&DefaultSnmp.FECParityShards, fecParityShards)
@@ -626,21 +647,23 @@ func (s *UDPSession) readLoop() {
type (
// Listener defines a server listening for connections
Listener struct {
block BlockCrypt
dataShards, parityShards int
fec *FEC // for fec init test
conn net.PacketConn
sessions map[string]*UDPSession
chAccepts chan *UDPSession
chDeadlinks chan net.Addr
headerSize int
die chan struct{}
rxbuf sync.Pool
rd atomic.Value
wd atomic.Value
block BlockCrypt // block encryption
dataShards int // FEC data shard
parityShards int // FEC parity shard
fec *FEC // FEC mock initialization
conn net.PacketConn // the underlying packet connection
sessions map[string]*UDPSession // all sessions accepted by this Listener
chAccepts chan *UDPSession // Listen() backlog
chDeadlinks chan net.Addr // session close queue
headerSize int // the overall header size added before KCP frame
die chan struct{} // notify the listener has closed
rd atomic.Value // read deadline for Accept()
wd atomic.Value
}
packet struct {
// incoming packet
inPacket struct {
from net.Addr
data []byte
}
@@ -648,7 +671,7 @@ type (
// monitor incoming data for all connections of server
func (l *Listener) monitor() {
chPacket := make(chan packet, rxQueueLimit)
chPacket := make(chan inPacket, rxQueueLimit)
go l.receiver(chPacket)
for {
select {
@@ -699,7 +722,7 @@ func (l *Listener) monitor() {
}
}
l.rxbuf.Put(raw)
xmitBuf.Put(raw)
case deadlink := <-l.chDeadlinks:
delete(l.sessions, deadlink.String())
case <-l.die:
@@ -708,11 +731,11 @@ func (l *Listener) monitor() {
}
}
func (l *Listener) receiver(ch chan packet) {
func (l *Listener) receiver(ch chan inPacket) {
for {
data := l.rxbuf.Get().([]byte)[:mtuLimit]
data := xmitBuf.Get().([]byte)[:mtuLimit]
if n, from, err := l.conn.ReadFrom(data); err == nil && n >= l.headerSize+IKCP_OVERHEAD {
ch <- packet{from, data[:n]}
ch <- inPacket{from, data[:n]}
} else if err != nil {
return
} else {
@@ -829,9 +852,6 @@ func ServeConn(block BlockCrypt, dataShards, parityShards int, conn net.PacketCo
l.parityShards = parityShards
l.block = block
l.fec = newFEC(rxFECMulti*(dataShards+parityShards), dataShards, parityShards)
l.rxbuf.New = func() interface{} {
return make([]byte, mtuLimit)
}
// calculate header size
if l.block != nil {