dnscrypt-proxy/vendor/github.com/quic-go/quic-go/multiplexer.go

76 lines
1.7 KiB
Go

package quic
import (
"fmt"
"net"
"sync"
"github.com/quic-go/quic-go/internal/utils"
)
var (
connMuxerOnce sync.Once
connMuxer multiplexer
)
type indexableConn interface{ LocalAddr() net.Addr }
type multiplexer interface {
AddConn(conn indexableConn)
RemoveConn(indexableConn) error
}
// The connMultiplexer listens on multiple net.PacketConns and dispatches
// incoming packets to the connection handler.
type connMultiplexer struct {
mutex sync.Mutex
conns map[string] /* LocalAddr().String() */ indexableConn
logger utils.Logger
}
var _ multiplexer = &connMultiplexer{}
func getMultiplexer() multiplexer {
connMuxerOnce.Do(func() {
connMuxer = &connMultiplexer{
conns: make(map[string]indexableConn),
logger: utils.DefaultLogger.WithPrefix("muxer"),
}
})
return connMuxer
}
func (m *connMultiplexer) index(addr net.Addr) string {
return addr.Network() + " " + addr.String()
}
func (m *connMultiplexer) AddConn(c indexableConn) {
m.mutex.Lock()
defer m.mutex.Unlock()
connIndex := m.index(c.LocalAddr())
p, ok := m.conns[connIndex]
if ok {
// Panics if we're already listening on this connection.
// This is a safeguard because we're introducing a breaking API change, see
// https://github.com/quic-go/quic-go/issues/3727 for details.
// We'll remove this at a later time, when most users of the library have made the switch.
panic("connection already exists") // TODO: write a nice message
}
m.conns[connIndex] = p
}
func (m *connMultiplexer) RemoveConn(c indexableConn) error {
m.mutex.Lock()
defer m.mutex.Unlock()
connIndex := m.index(c.LocalAddr())
if _, ok := m.conns[connIndex]; !ok {
return fmt.Errorf("cannote remove connection, connection is unknown")
}
delete(m.conns, connIndex)
return nil
}