64 lines
2.0 KiB
Go
64 lines
2.0 KiB
Go
// Package reuseport provides Listen and Dial functions that set socket
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// options in order to be able to reuse ports. You should only use this
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// package if you know what SO_REUSEADDR and SO_REUSEPORT are.
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//
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// For example:
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//
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// // listen on the same port. oh yeah.
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// l1, _ := reuse.Listen("tcp", "127.0.0.1:1234")
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// l2, _ := reuse.Listen("tcp", "127.0.0.1:1234")
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//
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// // dial from the same port. oh yeah.
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// l1, _ := reuse.Listen("tcp", "127.0.0.1:1234")
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// l2, _ := reuse.Listen("tcp", "127.0.0.1:1235")
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// c, _ := reuse.Dial("tcp", "127.0.0.1:1234", "127.0.0.1:1235")
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//
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// Note: cant dial self because tcp/ip stacks use 4-tuples to identify connections,
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// and doing so would clash.
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package reuseport
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import (
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"context"
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"fmt"
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"net"
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)
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// Available returns whether or not SO_REUSEPORT or equivalent behaviour is
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// available in the OS.
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func Available() bool {
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return true
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}
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var listenConfig = net.ListenConfig{
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Control: Control,
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}
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// Listen listens at the given network and address. see net.Listen
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// Returns a net.Listener created from a file discriptor for a socket
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// with SO_REUSEPORT and SO_REUSEADDR option set.
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func Listen(network, address string) (net.Listener, error) {
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return listenConfig.Listen(context.Background(), network, address)
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}
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// ListenPacket listens at the given network and address. see net.ListenPacket
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// Returns a net.Listener created from a file discriptor for a socket
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// with SO_REUSEPORT and SO_REUSEADDR option set.
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func ListenPacket(network, address string) (net.PacketConn, error) {
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return listenConfig.ListenPacket(context.Background(), network, address)
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}
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// Dial dials the given network and address. see net.Dialer.Dial
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// Returns a net.Conn created from a file descriptor for a socket
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// with SO_REUSEPORT and SO_REUSEADDR option set.
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func Dial(network, laddr, raddr string) (net.Conn, error) {
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nla, err := ResolveAddr(network, laddr)
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if err != nil {
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return nil, fmt.Errorf("failed to resolve local addr: %w", err)
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}
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d := net.Dialer{
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Control: Control,
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LocalAddr: nla,
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}
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return d.Dial(network, raddr)
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}
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