chainntnfs: use sync.Once to start notifiers.

This commit is contained in:
Roei Erez
2020-04-30 12:34:47 +03:00
parent 0cf63ae898
commit cfe0babd78
3 changed files with 101 additions and 92 deletions

View File

@@ -34,7 +34,7 @@ const (
type BitcoindNotifier struct {
epochClientCounter uint64 // To be used atomically.
started int32 // To be used atomically.
start sync.Once
stopped int32 // To be used atomically.
chainConn *chain.BitcoindClient
@@ -96,11 +96,41 @@ func New(chainConn *chain.BitcoindConn, chainParams *chaincfg.Params,
// Start connects to the running bitcoind node over websockets, registers for
// block notifications, and finally launches all related helper goroutines.
func (b *BitcoindNotifier) Start() error {
// Already started?
if atomic.AddInt32(&b.started, 1) != 1 {
var startErr error
b.start.Do(func() {
startErr = b.startNotifier()
})
return startErr
}
// Stop shutsdown the BitcoindNotifier.
func (b *BitcoindNotifier) Stop() error {
// Already shutting down?
if atomic.AddInt32(&b.stopped, 1) != 1 {
return nil
}
// Shutdown the rpc client, this gracefully disconnects from bitcoind,
// and cleans up all related resources.
b.chainConn.Stop()
close(b.quit)
b.wg.Wait()
// Notify all pending clients of our shutdown by closing the related
// notification channels.
for _, epochClient := range b.blockEpochClients {
close(epochClient.cancelChan)
epochClient.wg.Wait()
close(epochClient.epochChan)
}
b.txNotifier.TearDown()
return nil
}
func (b *BitcoindNotifier) startNotifier() error {
// Connect to bitcoind, and register for notifications on connected,
// and disconnected blocks.
if err := b.chainConn.Start(); err != nil {
@@ -131,33 +161,6 @@ func (b *BitcoindNotifier) Start() error {
return nil
}
// Stop shutsdown the BitcoindNotifier.
func (b *BitcoindNotifier) Stop() error {
// Already shutting down?
if atomic.AddInt32(&b.stopped, 1) != 1 {
return nil
}
// Shutdown the rpc client, this gracefully disconnects from bitcoind,
// and cleans up all related resources.
b.chainConn.Stop()
close(b.quit)
b.wg.Wait()
// Notify all pending clients of our shutdown by closing the related
// notification channels.
for _, epochClient := range b.blockEpochClients {
close(epochClient.cancelChan)
epochClient.wg.Wait()
close(epochClient.epochChan)
}
b.txNotifier.TearDown()
return nil
}
// notificationDispatcher is the primary goroutine which handles client
// notification registrations, as well as notification dispatches.
func (b *BitcoindNotifier) notificationDispatcher() {