深入分析GolangServer源码实现过程

func (srv *Server) Serve(l net.Listener) error {
	......
	for {
		rw, err := l.Accept()
		if err != nil {
			select {
			case  max {
					tempDelay = max
				}
				srv.logf("http: Accept error: %v; retrying in %v", err, tempDelay)
				time.Sleep(tempDelay)
				continue
			}
			return err
		}
		connCtx := ctx
		if cc := srv.ConnContext; cc != nil {
			connCtx = cc(connCtx, rw)
			if connCtx == nil {
				panic("ConnContext returned nil")
			}
		}
		tempDelay = 0
		c := srv.newConn(rw)
		c.setState(c.rwc, StateNew, runHooks) // before Serve can return
		go c.serve(connCtx)
	}
}

func (c *conn) serve(ctx context.Context) {
	......
	// HTTP/1.x from here on.
	ctx, cancelCtx := context.WithCancel(ctx)
	c.cancelCtx = cancelCtx
	defer cancelCtx()
	c.r = &connReader{conn: c}
	c.bufr = newBufioReader(c.r)
	c.bufw = newBufioWriterSize(checkConnErrorWriter{c}, 4

switch {
	case t.Chunked:
		if noResponseBodyExpected(t.RequestMethod) || !bodyAllowedForStatus(t.StatusCode) {
			t.Body = NoBody
		} else {
			t.Body = &body{src: internal.NewChunkedReader(r), hdr: msg, r: r, closing: t.Close}
		}
	case realLength == 0:
		t.Body = NoBody
	case realLength > 0:
		t.Body = &body{src: io.LimitReader(r, realLength), closing: t.Close}
	default:
		// realLength 

func (l *LimitedReader) Read(p []byte) (n int, err error) {
	if l.N  l.N {
		p = p[0:l.N]
	}
	n, err = l.R.Read(p)
	l.N -= int64(n)
	return
}

if requestBodyRemains(req.Body) {
    registerOnHitEOF(req.Body, w.conn.r.startBackgroundRead)
} else {
    w.conn.r.startBackgroundRead()
}

func (cr *connReader) backgroundRead() {
	n, err := cr.conn.rwc.Read(cr.byteBuf[:])
	cr.lock()
	if n == 1 {
		cr.hasByte = true
		......
	}
	if ne, ok := err.(net.Error); ok && cr.aborted && ne.Timeout() {
		// Ignore this error. It's the expected error from
		// another goroutine calling abortPendingRead.
	} else if err != nil {
		cr.handleReadError(err)
	}
	cr.aborted = false
	cr.inRead = false
	cr.unlock()
	cr.cond.Broadcast()
}
func (cr *connReader) handleReadError(_ error) {
	cr.conn.cancelCtx()
	cr.closeNotify()
}
// may be called from multiple goroutines.
func (cr *connReader) closeNotify() {
	res, _ := cr.conn.curReq.Load().(*response)
	if res != nil && atomic.CompareAndSwapInt32(&res.didCloseNotify, 0, 1) {
		res.closeNotifyCh