chore: release v0.6.0

.github/workflows/codeql-analysis.yml

@@ -39,10 +39,10 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v5
         with:
           go-version: "1.20"
 

.github/workflows/pr-check.yml

@@ -10,9 +10,9 @@ jobs:
         os: [ X64, ARM64 ]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version: ${{ matrix.go }}
 #      - uses: actions/cache@v2
@@ -28,9 +28,9 @@ jobs:
   windows-test:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version: "1.20"
 #      - uses: actions/cache@v2
@@ -44,9 +44,9 @@ jobs:
   style-test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version: 1.16
       - name: Check License Header

.github/workflows/release-check.yml

@@ -9,7 +9,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - name: Check Source Branch
         run: python2 -c "exit(0 if '${{ github.head_ref }}'.startswith('release') or '${{ github.head_ref }}'.startswith('hotfix') else 1)"

connection.go

@@ -19,7 +19,7 @@ import (
 	"time"
 )
 
-// CloseCallback will be called when the connection is closed.
+// CloseCallback will be called after the connection is closed.
 // Return: error is unused which will be ignored directly.
 type CloseCallback func(connection Connection) error
 

connection_errors.go

@@ -16,6 +16,7 @@ package netpoll
 
 import (
 	"fmt"
+	"net"
 	"syscall"
 )
 
@@ -51,6 +52,10 @@ func Exception(err error, suffix string) error {
 	return &exception{no: no, suffix: suffix}
 }
 
+var (
+	_ net.Error = (*exception)(nil)
+)
+
 type exception struct {
 	no     syscall.Errno
 	suffix string
@@ -88,6 +93,21 @@ func (e *exception) Unwrap() error {
 	return e.no
 }
 
+func (e *exception) Timeout() bool {
+	switch e.no {
+	case ErrDialTimeout, ErrReadTimeout, ErrWriteTimeout:
+		return true
+	}
+	if e.no.Timeout() {
+		return true
+	}
+	return false
+}
+
+func (e *exception) Temporary() bool {
+	return e.no.Temporary()
+}
+
 // Errors defined in netpoll
 var errnos = [...]string{
 	ErrnoMask & ErrConnClosed:     "connection has been closed",

connection_impl.go

@@ -45,8 +45,9 @@ type connection struct {
 	outputBuffer    *LinkBuffer
 	outputBarrier   *barrier
 	supportZeroCopy bool
-	maxSize         int // The maximum size of data between two Release().
-	bookSize        int // The size of data that can be read at once.
+	maxSize         int   // The maximum size of data between two Release().
+	bookSize        int   // The size of data that can be read at once.
+	state           int32 // 0: not connected, 1: connected, 2: disconnected. Connection state should be changed sequentially.
 }
 
 var (
@@ -323,6 +324,7 @@ func (c *connection) init(conn Conn, opts *options) (err error) {
 	c.bookSize, c.maxSize = pagesize, pagesize
 	c.inputBuffer, c.outputBuffer = NewLinkBuffer(pagesize), NewLinkBuffer()
 	c.outputBarrier = barrierPool.Get().(*barrier)
+	c.state = 0
 
 	c.initNetFD(conn) // conn must be *netFD{}
 	c.initFDOperator()
@@ -447,7 +449,7 @@ func (c *connection) waitReadWithTimeout(n int) (err error) {
 				return Exception(ErrReadTimeout, c.remoteAddr.String())
 			case err = <-c.readTrigger:
 				if err != nil {
-					return err
+					goto RET
 				}
 				continue
 			}

connection_lock.go

@@ -45,6 +45,7 @@ type key int32
 
 const (
 	closing key = iota
+	connecting
 	processing
 	flushing
 	// total must be at the bottom.

connection_onevent.go

@@ -26,6 +26,10 @@ import (
 
 var runTask = gopool.CtxGo
 
+func setRunner(runner func(ctx context.Context, f func())) {
+	runTask = runner
+}
+
 func disableGopool() error {
 	runTask = func(ctx context.Context, f func()) {
 		go f()
@@ -44,10 +48,11 @@ type gracefulExit interface {
 // OnPrepare, OnRequest, CloseCallback share the lock processing,
 // which is a CAS lock and can only be cleared by OnRequest.
 type onEvent struct {
-	ctx               context.Context
-	onConnectCallback atomic.Value
-	onRequestCallback atomic.Value
-	closeCallbacks    atomic.Value // value is latest *callbackNode
+	ctx                  context.Context
+	onConnectCallback    atomic.Value
+	onDisconnectCallback atomic.Value
+	onRequestCallback    atomic.Value
+	closeCallbacks       atomic.Value // value is latest *callbackNode
 }
 
 type callbackNode struct {
@@ -63,6 +68,14 @@ func (c *connection) SetOnConnect(onConnect OnConnect) error {
 	return nil
 }
 
+// SetOnDisconnect set the OnDisconnect callback.
+func (c *connection) SetOnDisconnect(onDisconnect OnDisconnect) error {
+	if onDisconnect != nil {
+		c.onDisconnectCallback.Store(onDisconnect)
+	}
+	return nil
+}
+
 // SetOnRequest initialize ctx when setting OnRequest.
 func (c *connection) SetOnRequest(onRequest OnRequest) error {
 	if onRequest == nil {
@@ -95,6 +108,7 @@ func (c *connection) AddCloseCallback(callback CloseCallback) error {
 func (c *connection) onPrepare(opts *options) (err error) {
 	if opts != nil {
 		c.SetOnConnect(opts.onConnect)
+		c.SetOnDisconnect(opts.onDisconnect)
 		c.SetOnRequest(opts.onRequest)
 		c.SetReadTimeout(opts.readTimeout)
 		c.SetWriteTimeout(opts.writeTimeout)
@@ -120,23 +134,36 @@ func (c *connection) onPrepare(opts *options) (err error) {
 func (c *connection) onConnect() {
 	var onConnect, _ = c.onConnectCallback.Load().(OnConnect)
 	if onConnect == nil {
+		atomic.StoreInt32(&c.state, 1)
+		return
+	}
+	if !c.lock(connecting) {
+		// it never happens because onDisconnect will not lock connecting if c.connected == 0
 		return
 	}
 	var onRequest, _ = c.onRequestCallback.Load().(OnRequest)
-	var connected int32
 	c.onProcess(
 		// only process when conn active and have unread data
 		func(c *connection) bool {
 			// if onConnect not called
-			if atomic.LoadInt32(&connected) == 0 {
+			if atomic.LoadInt32(&c.state) == 0 {
 				return true
 			}
 			// check for onRequest
 			return onRequest != nil && c.Reader().Len() > 0
 		},
 		func(c *connection) {
-			if atomic.CompareAndSwapInt32(&connected, 0, 1) {
+			if atomic.CompareAndSwapInt32(&c.state, 0, 1) {
 				c.ctx = onConnect(c.ctx, c)
+
+				if !c.IsActive() && atomic.CompareAndSwapInt32(&c.state, 1, 2) {
+					// since we hold connecting lock, so we should help to call onDisconnect here
+					var onDisconnect, _ = c.onDisconnectCallback.Load().(OnDisconnect)
+					if onDisconnect != nil {
+						onDisconnect(c.ctx, c)
+					}
+				}
+				c.unlock(connecting)
 				return
 			}
 			if onRequest != nil {
@@ -146,12 +173,44 @@ func (c *connection) onConnect() {
 	)
 }
 
+// when onDisconnect called, c.IsActive() must return false
+func (c *connection) onDisconnect() {
+	var onDisconnect, _ = c.onDisconnectCallback.Load().(OnDisconnect)
+	if onDisconnect == nil {
+		return
+	}
+	var onConnect, _ = c.onConnectCallback.Load().(OnConnect)
+	if onConnect == nil {
+		// no need lock if onConnect is nil
+		atomic.StoreInt32(&c.state, 2)
+		onDisconnect(c.ctx, c)
+		return
+	}
+	// check if OnConnect finished when onConnect != nil && onDisconnect != nil
+	if atomic.LoadInt32(&c.state) > 0 && c.lock(connecting) { // means OnConnect already finished
+		// protect onDisconnect run once
+		// if CAS return false, means OnConnect already helps to run onDisconnect
+		if atomic.CompareAndSwapInt32(&c.state, 1, 2) {
+			onDisconnect(c.ctx, c)
+		}
+		c.unlock(connecting)
+		return
+	}
+	// OnConnect is not finished yet, return and let onConnect helps to call onDisconnect
+	return
+}
+
 // onRequest is responsible for executing the closeCallbacks after the connection has been closed.
 func (c *connection) onRequest() (needTrigger bool) {
 	var onRequest, ok = c.onRequestCallback.Load().(OnRequest)
 	if !ok {
 		return true
 	}
+	// wait onConnect finished first
+	if atomic.LoadInt32(&c.state) == 0 && c.onConnectCallback.Load() != nil {
+		// let onConnect to call onRequest
+		return
+	}
 	processed := c.onProcess(
 		// only process when conn active and have unread data
 		func(c *connection) bool {
@@ -206,7 +265,7 @@ func (c *connection) onProcess(isProcessable func(c *connection) bool, process f
 			}
 			process(c)
 		}
-		// Handling callback if connection has been closed.
+		// handling callback if connection has been closed.
 		if closedBy != none {
 			//  if closed by user when processing, it "may" needs detach
 			needDetach := closedBy == user
@@ -219,15 +278,24 @@ func (c *connection) onProcess(isProcessable func(c *connection) bool, process f
 			return
 		}
 		c.unlock(processing)
-		// Double check when exiting.
+		// Note: Poller's closeCallback call will try to get processing lock failed but here already neer to unlock processing.
+		//       So here we need to check connection state again, to avoid connection leak
+		// double check close state
+		if c.status(closing) != 0 && c.lock(processing) {
+			// poller will get the processing lock failed, here help poller do closeCallback
+			// fd must already detach by poller
+			c.closeCallback(false, false)
+			panicked = false
+			return
+		}
+		// double check isProcessable
 		if isProcessable(c) && c.lock(processing) {
 			goto START
 		}
 		// task exits
 		panicked = false
 		return
 	}
-
 	runTask(c.ctx, task)
 	return true
 }

connection_reactor.go

@@ -30,6 +30,10 @@ func (c *connection) onHup(p Poll) error {
 	}
 	c.triggerRead(Exception(ErrEOF, "peer close"))
 	c.triggerWrite(Exception(ErrConnClosed, "peer close"))
+
+	// call Disconnect callback first
+	c.onDisconnect()
+
 	// It depends on closing by user if OnConnect and OnRequest is nil, otherwise it needs to be released actively.
 	// It can be confirmed that the OnRequest goroutine has been exited before closeCallback executing,
 	// and it is safe to close the buffer at this time.

connection_test.go

@@ -504,10 +504,10 @@ func TestParallelShortConnection(t *testing.T) {
 	var received int64
 	el, err := NewEventLoop(func(ctx context.Context, connection Connection) error {
 		data, err := connection.Reader().Next(connection.Reader().Len())
+		atomic.AddInt64(&received, int64(len(data)))
 		if err != nil {
 			return err
 		}
-		atomic.AddInt64(&received, int64(len(data)))
 		//t.Logf("conn[%s] received: %d, active: %v", connection.RemoteAddr(), len(data), connection.IsActive())
 		return nil
 	})
@@ -536,10 +536,13 @@ func TestParallelShortConnection(t *testing.T) {
 	}
 	wg.Wait()
 
-	for atomic.LoadInt64(&received) < int64(totalSize) {
+	count := 100
+	for count > 0 && atomic.LoadInt64(&received) < int64(totalSize) {
 		t.Logf("received: %d, except: %d", atomic.LoadInt64(&received), totalSize)
 		time.Sleep(time.Millisecond * 100)
+		count--
 	}
+	Equal(t, atomic.LoadInt64(&received), int64(totalSize))
 }
 
 func TestConnectionServerClose(t *testing.T) {

eventloop.go

@@ -34,6 +34,20 @@ type EventLoop interface {
 	Shutdown(ctx context.Context) error
 }
 
+/* The Connection Callback Sequence Diagram
+| Connection State                     | Callback Function | Notes
+|   Connected but not initialized      |    OnPrepare      | Conn is not registered into poller
+|   Connected and initialized          |    OnConnect      | Conn is ready for read or write
+|   Read first byte                    |    OnRequest      | Conn is ready for read or write
+|   Peer closed but conn is active     |    OnDisconnect   | Conn access will race with OnRequest function
+|   Self closed and conn is closed     |    CloseCallback  | Conn is destroyed
+
+Execution Order:
+  OnPrepare => OnConnect => OnRequest      => CloseCallback
+                            OnDisconnect
+Note: only OnRequest and OnDisconnect will be executed in parallel
+*/
+
 // OnPrepare is used to inject custom preparation at connection initialization,
 // which is optional but important in some scenarios. For example, a qps limiter
 // can be set by closing overloaded connections directly in OnPrepare.
@@ -63,6 +77,11 @@ type OnPrepare func(connection Connection) context.Context
 //  }
 type OnConnect func(ctx context.Context, connection Connection) context.Context
 
+// OnDisconnect is called once connection is going to be closed.
+// OnDisconnect must return as quick as possible because it will block poller.
+// OnDisconnect is different from CloseCallback, you could check with "The Connection Callback Sequence Diagram" section.
+type OnDisconnect func(ctx context.Context, connection Connection)
+
 // OnRequest defines the function for handling connection. When data is sent from the connection peer,
 // netpoll actively reads the data in LT mode and places it in the connection's input buffer.
 // Generally, OnRequest starts handling the data in the following way: