chainntnfs: declare common ErrChainNotifierShuttingDown for all backends

chainntnfs/bitcoindnotify/bitcoind.go

@@ -26,11 +26,6 @@ const (
 )
 
 var (
-	// ErrChainNotifierShuttingDown is used when we are trying to
-	// measure a spend notification when notifier is already stopped.
-	ErrChainNotifierShuttingDown = errors.New("chainntnfs: system interrupt " +
-		"while attempting to register for spend notification.")
-
 	// ErrTransactionNotFound is an error returned when we attempt to find a
 	// transaction by manually scanning the chain within a specific range
 	// but it is not found.
@@ -498,7 +493,6 @@ func (b *BitcoindNotifier) confDetailsFromTxIndex(txid *chainhash.Hash,
 			fmt.Errorf("unable to get block hash %v for "+
 				"historical dispatch: %v", rawTxRes.BlockHash, err)
 	}
-
 	block, err := b.chainConn.GetBlockVerbose(blockHash)
 	if err != nil {
 		return nil, chainntnfs.TxNotFoundIndex,
@@ -559,7 +553,7 @@ func (b *BitcoindNotifier) confDetailsManually(confRequest chainntnfs.ConfReques
 		select {
 		case <-b.quit:
 			return nil, chainntnfs.TxNotFoundManually,
-				ErrChainNotifierShuttingDown
+				chainntnfs.ErrChainNotifierShuttingDown
 		default:
 		}
 
@@ -728,7 +722,7 @@ func (b *BitcoindNotifier) RegisterSpendNtfn(outpoint *wire.OutPoint,
 		select {
 		case b.notificationRegistry <- historicalDispatch:
 		case <-b.quit:
-			return nil, ErrChainNotifierShuttingDown
+			return nil, chainntnfs.ErrChainNotifierShuttingDown
 		}
 
 		return ntfn.Event, nil
@@ -805,7 +799,7 @@ func (b *BitcoindNotifier) RegisterSpendNtfn(outpoint *wire.OutPoint,
 	select {
 	case b.notificationRegistry <- historicalDispatch:
 	case <-b.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 
 	return ntfn.Event, nil
@@ -829,7 +823,7 @@ func (b *BitcoindNotifier) dispatchSpendDetailsManually(
 		// processing the next height.
 		select {
 		case <-b.quit:
-			return ErrChainNotifierShuttingDown
+			return chainntnfs.ErrChainNotifierShuttingDown
 		default:
 		}
 
@@ -923,7 +917,7 @@ func (b *BitcoindNotifier) RegisterConfirmationsNtfn(txid *chainhash.Hash,
 	case b.notificationRegistry <- dispatch:
 		return ntfn.Event, nil
 	case <-b.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 }
 

chainntnfs/btcdnotify/btcd.go

@@ -26,13 +26,6 @@ const (
 	notifierType = "btcd"
 )
 
-var (
-	// ErrChainNotifierShuttingDown is used when we are trying to
-	// measure a spend notification when notifier is already stopped.
-	ErrChainNotifierShuttingDown = errors.New("chainntnfs: system interrupt " +
-		"while attempting to register for spend notification.")
-)
-
 // chainUpdate encapsulates an update to the current main chain. This struct is
 // used as an element within an unbounded queue in order to avoid blocking the
 // main rpc dispatch rule.
@@ -610,7 +603,7 @@ func (b *BtcdNotifier) confDetailsManually(confRequest chainntnfs.ConfRequest,
 		select {
 		case <-b.quit:
 			return nil, chainntnfs.TxNotFoundManually,
-				ErrChainNotifierShuttingDown
+				chainntnfs.ErrChainNotifierShuttingDown
 		default:
 		}
 
@@ -964,7 +957,7 @@ func (b *BtcdNotifier) RegisterConfirmationsNtfn(txid *chainhash.Hash,
 	case b.notificationRegistry <- dispatch:
 		return ntfn.Event, nil
 	case <-b.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 }
 

chainntnfs/interface.go

@@ -1,6 +1,7 @@
 package chainntnfs
 
 import (
+	"errors"
 	"fmt"
 	"sync"
 
@@ -9,6 +10,12 @@ import (
 	"github.com/btcsuite/btcd/wire"
 )
 
+var (
+	// ErrChainNotifierShuttingDown is used when we are trying to
+	// measure a spend notification when notifier is already stopped.
+	ErrChainNotifierShuttingDown = errors.New("chain notifier shutting down")
+)
+
 // TxConfStatus denotes the status of a transaction's lookup.
 type TxConfStatus uint8
 

chainntnfs/neutrinonotify/neutrino.go

@@ -27,13 +27,6 @@ const (
 	notifierType = "neutrino"
 )
 
-var (
-	// ErrChainNotifierShuttingDown is used when we are trying to
-	// measure a spend notification when notifier is already stopped.
-	ErrChainNotifierShuttingDown = errors.New("chainntnfs: system interrupt " +
-		"while attempting to register for spend notification.")
-)
-
 // NeutrinoNotifier is a version of ChainNotifier that's backed by the neutrino
 // Bitcoin light client. Unlike other implementations, this implementation
 // speaks directly to the p2p network. As a result, this implementation of the
@@ -503,7 +496,7 @@ func (n *NeutrinoNotifier) historicalConfDetails(confRequest chainntnfs.ConfRequ
 		// processing the next height.
 		select {
 		case <-n.quit:
-			return nil, ErrChainNotifierShuttingDown
+			return nil, chainntnfs.ErrChainNotifierShuttingDown
 		default:
 		}
 
@@ -710,13 +703,13 @@ func (n *NeutrinoNotifier) RegisterSpendNtfn(outpoint *wire.OutPoint,
 		errChan:       errChan,
 	}:
 	case <-n.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 
 	select {
 	case err = <-errChan:
 	case <-n.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 	if err != nil {
 		return nil, fmt.Errorf("unable to update filter: %v", err)
@@ -856,13 +849,13 @@ func (n *NeutrinoNotifier) RegisterConfirmationsNtfn(txid *chainhash.Hash,
 		errChan: errChan,
 	}:
 	case <-n.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 
 	select {
 	case err = <-errChan:
 	case <-n.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 	if err != nil {
 		return nil, fmt.Errorf("unable to update filter: %v", err)
@@ -879,7 +872,7 @@ func (n *NeutrinoNotifier) RegisterConfirmationsNtfn(txid *chainhash.Hash,
 	select {
 	case n.notificationRegistry <- dispatch:
 	case <-n.quit:
-		return nil, ErrChainNotifierShuttingDown
+		return nil, chainntnfs.ErrChainNotifierShuttingDown
 	}
 
 	return ntfn.Event, nil