From 710824c3ce9f8084517e8ab099d57f9060f62061 Mon Sep 17 00:00:00 2001 From: WeidiDeng Date: Sat, 1 Jul 2023 06:31:26 +0800 Subject: core: Embed net.UDPConn to gain optimizations (#5606) Co-authored-by: Matt Holt --- listeners.go | 40 +++++++++++++++++----------------------- 1 file changed, 17 insertions(+), 23 deletions(-) diff --git a/listeners.go b/listeners.go index a12d67f..fe5ad0c 100644 --- a/listeners.go +++ b/listeners.go @@ -196,7 +196,8 @@ func (na NetworkAddress) listen(ctx context.Context, portOffset uint, config net if err != nil { return nil, err } - ln = &fakeClosePacketConn{sharedPacketConn: sharedPc.(*sharedPacketConn)} + spc := sharedPc.(*sharedPacketConn) + ln = &fakeClosePacketConn{spc: spc, UDPConn: spc.PacketConn.(*net.UDPConn)} } if strings.HasPrefix(na.Network, "ip") { ln, err = config.ListenPacket(ctx, na.Network, address) @@ -668,37 +669,30 @@ func fakeClosedErr(l interface{ Addr() net.Addr }) error { // socket is actually left open. var errFakeClosed = fmt.Errorf("listener 'closed' 😉") -// fakeClosePacketConn is like fakeCloseListener, but for PacketConns. +// fakeClosePacketConn is like fakeCloseListener, but for PacketConns, +// or more specifically, *net.UDPConn type fakeClosePacketConn struct { - closed int32 // accessed atomically; belongs to this struct only - *sharedPacketConn // embedded, so we also become a net.PacketConn + closed int32 // accessed atomically; belongs to this struct only + spc *sharedPacketConn // its key is used in Close + *net.UDPConn // embedded, so we also become a net.PacketConn and enable several other optimizations done by quic-go } +// interface guard for extra optimizations +// needed by QUIC implementation: https://github.com/caddyserver/caddy/issues/3998, https://github.com/caddyserver/caddy/issues/5605 +var _ quic.OOBCapablePacketConn = (*fakeClosePacketConn)(nil) + +// https://pkg.go.dev/golang.org/x/net/ipv4#NewPacketConn is used by quic-go and requires a net.PacketConn type assertable to a net.Conn, +// but doesn't actually use these methods, the only methods needed are `ReadMsgUDP` and `SyscallConn`. +var _ net.Conn = (*fakeClosePacketConn)(nil) + +// Close won't close the underlying socket unless there is no more reference, then listenerPool will close it. func (fcpc *fakeClosePacketConn) Close() error { if atomic.CompareAndSwapInt32(&fcpc.closed, 0, 1) { - _, _ = listenerPool.Delete(fcpc.sharedPacketConn.key) + _, _ = listenerPool.Delete(fcpc.spc.key) } return nil } -// Supports QUIC implementation: https://github.com/caddyserver/caddy/issues/3998 -func (fcpc fakeClosePacketConn) SetReadBuffer(bytes int) error { - if conn, ok := fcpc.PacketConn.(interface{ SetReadBuffer(int) error }); ok { - return conn.SetReadBuffer(bytes) - } - return fmt.Errorf("SetReadBuffer() not implemented for %T", fcpc.PacketConn) -} - -// Supports QUIC implementation: https://github.com/caddyserver/caddy/issues/3998 -func (fcpc fakeClosePacketConn) SyscallConn() (syscall.RawConn, error) { - if conn, ok := fcpc.PacketConn.(interface { - SyscallConn() (syscall.RawConn, error) - }); ok { - return conn.SyscallConn() - } - return nil, fmt.Errorf("SyscallConn() not implemented for %T", fcpc.PacketConn) -} - type fakeCloseQuicListener struct { closed int32 // accessed atomically; belongs to this struct only *sharedQuicListener // embedded, so we also become a quic.EarlyListener -- cgit v1.2.3