multi: Use atomic types in exported modules.

addrmgr/addrmanager.go

@@ -1,5 +1,5 @@
 // Copyright (c) 2013-2014 The btcsuite developers
-// Copyright (c) 2015-2023 The Decred developers
+// Copyright (c) 2015-2024 The Decred developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
@@ -72,13 +72,12 @@ type AddrManager struct {
 	// serialized and saved to the file system.
 	addrChanged bool
 
-	// started signals whether the address manager has been started.  Its value
-	// is 1 or more if started.
-	started int32
+	// started signals whether the address manager has been started.
+	started atomic.Bool
 
 	// shutdown signals whether a shutdown of the address manager has been
-	// initiated.  Its value is 1 or more if a shutdown is done or in progress.
-	shutdown int32
+	// initiated.
+	shutdown atomic.Bool
 
 	// The following fields are used for lifecycle management of the
 	// address manager.
@@ -623,7 +622,7 @@ func (a *AddrManager) deserializePeers(filePath string) error {
 // This function is safe for concurrent access.
 func (a *AddrManager) Start() {
 	// Return early if the address manager has already been started.
-	if atomic.AddInt32(&a.started, 1) != 1 {
+	if !a.started.CompareAndSwap(false, true) {
 		return
 	}
 
@@ -642,7 +641,7 @@ func (a *AddrManager) Start() {
 // This function is safe for concurrent access.
 func (a *AddrManager) Stop() error {
 	// Return early if the address manager has already been stopped.
-	if atomic.AddInt32(&a.shutdown, 1) != 1 {
+	if !a.shutdown.CompareAndSwap(false, true) {
 		log.Warnf("Address manager is already in the process of shutting down")
 		return nil
 	}

addrmgr/go.mod

@@ -1,6 +1,6 @@
 module github.com/decred/dcrd/addrmgr/v2
 
-go 1.17
+go 1.19
 
 require (
 	github.com/decred/dcrd/chaincfg/chainhash v1.0.4

connmgr/connmanager.go

@@ -1,5 +1,5 @@
 // Copyright (c) 2016 The btcsuite developers
-// Copyright (c) 2017-2023 The Decred developers
+// Copyright (c) 2017-2024 The Decred developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
@@ -56,13 +56,11 @@ const (
 // ConnReq is the connection request to a network address. If permanent, the
 // connection will be retried on disconnection.
 type ConnReq struct {
-	// The following variables must only be used atomically.
-	//
 	// id is the unique identifier for this connection request.
-	//
+	id atomic.Uint64
+
 	// state is the current connection state for this connection request.
-	id    uint64
-	state uint32
+	state atomic.Uint32
 
 	// The following fields are owned by the connection handler and must not
 	// be accessed outside of it.
@@ -87,17 +85,17 @@ type ConnReq struct {
 
 // updateState updates the state of the connection request.
 func (c *ConnReq) updateState(state ConnState) {
-	atomic.StoreUint32(&c.state, uint32(state))
+	c.state.Store(uint32(state))
 }
 
 // ID returns a unique identifier for the connection request.
 func (c *ConnReq) ID() uint64 {
-	return atomic.LoadUint64(&c.id)
+	return c.id.Load()
 }
 
 // State is the connection state of the requested connection.
 func (c *ConnReq) State() ConnState {
-	return ConnState(atomic.LoadUint32(&c.state))
+	return ConnState(c.state.Load())
 }
 
 // String returns a human-readable string for the connection request.
@@ -209,11 +207,9 @@ type handleForEachConnReq struct {
 
 // ConnManager provides a manager to handle network connections.
 type ConnManager struct {
-	// The following variables must only be used atomically.
-	//
 	// connReqCount is the number of connection requests that have been made and
 	// is primarily used to assign unique connection request IDs.
-	connReqCount uint64
+	connReqCount atomic.Uint64
 
 	// assignIDMtx synchronizes the assignment of an ID to a connection request
 	// with overall connection request count above.
@@ -467,7 +463,8 @@ func (cm *ConnManager) newConnReq(ctx context.Context) {
 		return
 	}
 
-	c := &ConnReq{id: atomic.AddUint64(&cm.connReqCount, 1)}
+	c := &ConnReq{}
+	c.id.Store(cm.connReqCount.Add(1))
 
 	// Submit a request of a pending connection attempt to the connection
 	// manager. By registering the id before the connection is even
@@ -545,7 +542,7 @@ func (cm *ConnManager) Connect(ctx context.Context, c *ConnReq) {
 	var doRegisterPending bool
 	cm.assignIDMtx.Lock()
 	if c.ID() == 0 {
-		atomic.StoreUint64(&c.id, atomic.AddUint64(&cm.connReqCount, 1))
+		c.id.Store(cm.connReqCount.Add(1))
 		doRegisterPending = true
 	}
 	cm.assignIDMtx.Unlock()
@@ -716,7 +713,7 @@ func (cm *ConnManager) Run(ctx context.Context) {
 	// Start enough outbound connections to reach the target number when not
 	// in manual connect mode.
 	if cm.cfg.GetNewAddress != nil {
-		curConnReqCount := atomic.LoadUint64(&cm.connReqCount)
+		curConnReqCount := cm.connReqCount.Load()
 		for i := curConnReqCount; i < uint64(cm.cfg.TargetOutbound); i++ {
 			go cm.newConnReq(ctx)
 		}

connmgr/connmanager_test.go

@@ -1,5 +1,5 @@
 // Copyright (c) 2016 The btcsuite developers
-// Copyright (c) 2019-2022 The Decred developers
+// Copyright (c) 2019-2024 The Decred developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
@@ -405,11 +405,11 @@ func TestNetworkFailure(t *testing.T) {
 	var closeOnce sync.Once
 	const targetOutbound = 5
 	const retryTimeout = time.Millisecond * 5
-	var dials uint32
+	var dials atomic.Uint32
 	reachedMaxFailedAttempts := make(chan struct{})
 	connMgrDone := make(chan struct{})
 	errDialer := func(ctx context.Context, network, addr string) (net.Conn, error) {
-		totalDials := atomic.AddUint32(&dials, 1)
+		totalDials := dials.Add(1)
 		if totalDials >= maxFailedAttempts {
 			closeOnce.Do(func() { close(reachedMaxFailedAttempts) })
 			<-connMgrDone
@@ -447,7 +447,7 @@ func TestNetworkFailure(t *testing.T) {
 	// Ensure the number of dial attempts does not exceed the max number of
 	// failed attempts plus the number of potential retries during the
 	// additional waiting period.
-	gotDials := atomic.LoadUint32(&dials)
+	gotDials := dials.Load()
 	wantMaxDials := uint32(maxFailedAttempts + targetOutbound)
 	if gotDials > wantMaxDials {
 		t.Fatalf("unexpected number of dials - got %v, want <= %v", gotDials,
@@ -468,11 +468,11 @@ func TestMultipleFailedConns(t *testing.T) {
 	}()
 
 	const targetFailed = 5
-	var dials uint32
+	var dials atomic.Uint32
 	var closeOnce sync.Once
 	hitTargetFailed := make(chan struct{})
 	errDialer := func(ctx context.Context, network, addr string) (net.Conn, error) {
-		totalDials := atomic.AddUint32(&dials, 1)
+		totalDials := dials.Add(1)
 		if totalDials >= targetFailed {
 			closeOnce.Do(func() { close(hitTargetFailed) })
 		}

connmgr/go.mod

@@ -1,6 +1,6 @@
 module github.com/decred/dcrd/connmgr/v3
 
-go 1.17
+go 1.19
 
 require (
 	github.com/decred/dcrd/wire v1.6.0

database/ffldb/interface_test.go

@@ -1,5 +1,5 @@
 // Copyright (c) 2015-2016 The btcsuite developers
-// Copyright (c) 2016-2020 The Decred developers
+// Copyright (c) 2016-2024 The Decred developers
 // Use of this source code is governed by an ISC
 // license that can be found in the LICENSE file.
 
@@ -2163,17 +2163,17 @@ func testConcurrentClose(tc *testContext) bool {
 	// Start up a few readers and wait for them to acquire views.  Each
 	// reader waits for a signal to complete to ensure the transactions stay
 	// open until they are explicitly signalled to be closed.
-	var activeReaders int32
+	var activeReaders atomic.Int32
 	numReaders := 3
 	started := make(chan struct{})
 	finishReaders := make(chan struct{})
 	resultChan := make(chan bool, numReaders+1)
 	reader := func() {
 		err := tc.db.View(func(tx database.Tx) error {
-			atomic.AddInt32(&activeReaders, 1)
+			activeReaders.Add(1)
 			started <- struct{}{}
 			<-finishReaders
-			atomic.AddInt32(&activeReaders, -1)
+			activeReaders.Add(-1)
 			return nil
 		})
 		if err != nil {
@@ -2212,7 +2212,7 @@ func testConcurrentClose(tc *testContext) bool {
 	// active readers open.
 	time.AfterFunc(time.Millisecond*250, func() { close(finishReaders) })
 	<-dbClosed
-	if nr := atomic.LoadInt32(&activeReaders); nr != 0 {
+	if nr := activeReaders.Load(); nr != 0 {
 		tc.t.Errorf("Close did not appear to block with active "+
 			"readers: %d active", nr)
 		return false

database/go.mod

@@ -1,6 +1,6 @@
 module github.com/decred/dcrd/database/v3
 
-go 1.17
+go 1.19
 
 require (
 	github.com/decred/dcrd/chaincfg/chainhash v1.0.4

peer/go.mod

@@ -1,6 +1,6 @@
 module github.com/decred/dcrd/peer/v3
 
-go 1.17
+go 1.19
 
 require (
 	github.com/davecgh/go-spew v1.1.1