replace zxq.co/ripple/hanayo

vendor/github.com/valyala/fasthttp/fasthttputil/pipeconns.go

@@ -0,0 +1,221 @@
+package fasthttputil
+
+import (
+	"errors"
+	"io"
+	"net"
+	"sync"
+	"time"
+)
+
+// NewPipeConns returns new bi-directonal connection pipe.
+func NewPipeConns() *PipeConns {
+	ch1 := make(chan *byteBuffer, 4)
+	ch2 := make(chan *byteBuffer, 4)
+
+	pc := &PipeConns{
+		stopCh: make(chan struct{}),
+	}
+	pc.c1.rCh = ch1
+	pc.c1.wCh = ch2
+	pc.c2.rCh = ch2
+	pc.c2.wCh = ch1
+	pc.c1.pc = pc
+	pc.c2.pc = pc
+	return pc
+}
+
+// PipeConns provides bi-directional connection pipe,
+// which use in-process memory as a transport.
+//
+// PipeConns must be created by calling NewPipeConns.
+//
+// PipeConns has the following additional features comparing to connections
+// returned from net.Pipe():
+//
+//   * It is faster.
+//   * It buffers Write calls, so there is no need to have concurrent goroutine
+//     calling Read in order to unblock each Write call.
+type PipeConns struct {
+	c1         pipeConn
+	c2         pipeConn
+	stopCh     chan struct{}
+	stopChLock sync.Mutex
+}
+
+// Conn1 returns the first end of bi-directional pipe.
+//
+// Data written to Conn1 may be read from Conn2.
+// Data written to Conn2 may be read from Conn1.
+func (pc *PipeConns) Conn1() net.Conn {
+	return &pc.c1
+}
+
+// Conn2 returns the second end of bi-directional pipe.
+//
+// Data written to Conn2 may be read from Conn1.
+// Data written to Conn1 may be read from Conn2.
+func (pc *PipeConns) Conn2() net.Conn {
+	return &pc.c2
+}
+
+// Close closes pipe connections.
+func (pc *PipeConns) Close() error {
+	pc.stopChLock.Lock()
+	select {
+	case <-pc.stopCh:
+	default:
+		close(pc.stopCh)
+	}
+	pc.stopChLock.Unlock()
+
+	return nil
+}
+
+type pipeConn struct {
+	b  *byteBuffer
+	bb []byte
+
+	rCh chan *byteBuffer
+	wCh chan *byteBuffer
+	pc  *PipeConns
+}
+
+func (c *pipeConn) Write(p []byte) (int, error) {
+	b := acquireByteBuffer()
+	b.b = append(b.b[:0], p...)
+
+	select {
+	case <-c.pc.stopCh:
+		releaseByteBuffer(b)
+		return 0, errConnectionClosed
+	default:
+	}
+
+	select {
+	case c.wCh <- b:
+	default:
+		select {
+		case c.wCh <- b:
+		case <-c.pc.stopCh:
+			releaseByteBuffer(b)
+			return 0, errConnectionClosed
+		}
+	}
+
+	return len(p), nil
+}
+
+func (c *pipeConn) Read(p []byte) (int, error) {
+	mayBlock := true
+	nn := 0
+	for len(p) > 0 {
+		n, err := c.read(p, mayBlock)
+		nn += n
+		if err != nil {
+			if !mayBlock && err == errWouldBlock {
+				err = nil
+			}
+			return nn, err
+		}
+		p = p[n:]
+		mayBlock = false
+	}
+
+	return nn, nil
+}
+
+func (c *pipeConn) read(p []byte, mayBlock bool) (int, error) {
+	if len(c.bb) == 0 {
+		if err := c.readNextByteBuffer(mayBlock); err != nil {
+			return 0, err
+		}
+	}
+	n := copy(p, c.bb)
+	c.bb = c.bb[n:]
+
+	return n, nil
+}
+
+func (c *pipeConn) readNextByteBuffer(mayBlock bool) error {
+	releaseByteBuffer(c.b)
+	c.b = nil
+
+	select {
+	case c.b = <-c.rCh:
+	default:
+		if !mayBlock {
+			return errWouldBlock
+		}
+		select {
+		case c.b = <-c.rCh:
+		case <-c.pc.stopCh:
+			return io.EOF
+		}
+	}
+
+	c.bb = c.b.b
+	return nil
+}
+
+var (
+	errWouldBlock       = errors.New("would block")
+	errConnectionClosed = errors.New("connection closed")
+	errNoDeadlines      = errors.New("deadline not supported")
+)
+
+func (c *pipeConn) Close() error {
+	return c.pc.Close()
+}
+
+func (c *pipeConn) LocalAddr() net.Addr {
+	return pipeAddr(0)
+}
+
+func (c *pipeConn) RemoteAddr() net.Addr {
+	return pipeAddr(0)
+}
+
+func (c *pipeConn) SetDeadline(t time.Time) error {
+	return errNoDeadlines
+}
+
+func (c *pipeConn) SetReadDeadline(t time.Time) error {
+	return c.SetDeadline(t)
+}
+
+func (c *pipeConn) SetWriteDeadline(t time.Time) error {
+	return c.SetDeadline(t)
+}
+
+type pipeAddr int
+
+func (pipeAddr) Network() string {
+	return "pipe"
+}
+
+func (pipeAddr) String() string {
+	return "pipe"
+}
+
+type byteBuffer struct {
+	b []byte
+}
+
+func acquireByteBuffer() *byteBuffer {
+	return byteBufferPool.Get().(*byteBuffer)
+}
+
+func releaseByteBuffer(b *byteBuffer) {
+	if b != nil {
+		byteBufferPool.Put(b)
+	}
+}
+
+var byteBufferPool = &sync.Pool{
+	New: func() interface{} {
+		return &byteBuffer{
+			b: make([]byte, 1024),
+		}
+	},
+}