51 lines
1.1 KiB
Go
51 lines
1.1 KiB
Go
package node
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import (
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"io"
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"log"
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"net"
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"net/netip"
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"sync"
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)
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// ----------------------------------------------------------------------------
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type connWriter struct {
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lock sync.Mutex
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conn *net.UDPConn
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}
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func newConnWriter(conn *net.UDPConn) *connWriter {
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return &connWriter{conn: conn}
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}
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func (w *connWriter) WriteTo(packet []byte, addr netip.AddrPort) {
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// Even though a conn is safe for concurrent use, it turns out that a mutex
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// in Go is more fair when there's contention. Without this lock, control
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// packets may fail to be sent in a timely manner causing timeouts.
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w.lock.Lock()
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if _, err := w.conn.WriteToUDPAddrPort(packet, addr); err != nil {
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log.Printf("Failed to write to UDP port: %v", err)
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}
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w.lock.Unlock()
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}
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// ----------------------------------------------------------------------------
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type ifWriter struct {
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lock sync.Mutex
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iface io.ReadWriteCloser
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}
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func newIFWriter(iface io.ReadWriteCloser) *ifWriter {
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return &ifWriter{iface: iface}
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}
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func (w *ifWriter) Write(packet []byte) {
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w.lock.Lock()
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if _, err := w.iface.Write(packet); err != nil {
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log.Fatalf("Failed to write to interface: %v", err)
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}
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w.lock.Unlock()
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}
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