You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: protocol.go
    path of file: ./repos/goldfish/vendor/github.com/armon/go-proxyproto
    
    the code of the file until where you have to start completion: package proxyproto

import (
	"bufio"
	"bytes"
	"errors"
	"fmt"
	"io"
	"log"
	"net"
	"strconv"
	"strings"
	"sync"
	"time"
)

var (
	// prefix is the string we look for at the start of a connection
	// to check if this connection is using the proxy protocol
	prefix    = []byte("PROXY ")
	prefixLen
    
func (p *Listener) Accept() (net.Conn, error) {
	// Get the underlying connection
	conn, err := p.Listener.Accept()
	if err != nil {
		return nil, err
	}
	var useConnRemoteAddr bool
	if p.SourceCheck != nil {
		allowed, err := p.SourceCheck(conn.RemoteAddr())
		if err != nil {
			return nil, err
		}
		if !allowed {
			useConnRemoteAddr = true
		}
	}
	newConn := NewConn(conn, p.ProxyHeaderTimeout)
	newConn.useConnRemoteAddr = useConnRemoteAddr
	return newConn, nil
}