Use fmt precision to limit string length

The previous code used string slices to limit the length of certain
fields like endpoint or sandbox IDs.  This assumes that these strings
are at least as long as the slice length.  Unfortunately, some sandbox
IDs can be smaller than 7 characters.   This fix addresses this issue
by systematically converting format string calls that were taking
fixed-slice arguments to use a precision specifier in the string format
itself.  From the golang fmt package documentation:

    For strings, byte slices and byte arrays, however, precision limits
    the length of the input to be formatted (not the size of the output),
    truncating if necessary. Normally it is measured in runes, but for
    these types when formatted with the %x or %X format it is measured
    in bytes.

This nicely fits the desired behavior: it will limit the number of
runes considered for string interpolation to the precision value.

Signed-off-by: Chris Telfer <ctelfer@docker.com>

drivers/bridge/bridge.go

@@ -775,7 +775,7 @@ func (d *driver) deleteNetwork(nid string) error {
 		}
 
 		if err := d.storeDelete(ep); err != nil {
-			logrus.Warnf("Failed to remove bridge endpoint %s from store: %v", ep.id[0:7], err)
+			logrus.Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
 		}
 	}
 
@@ -1050,7 +1050,7 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,
 	}
 
 	if err = d.storeUpdate(endpoint); err != nil {
-		return fmt.Errorf("failed to save bridge endpoint %s to store: %v", endpoint.id[0:7], err)
+		return fmt.Errorf("failed to save bridge endpoint %.7s to store: %v", endpoint.id, err)
 	}
 
 	return nil
@@ -1116,7 +1116,7 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	}
 
 	if err := d.storeDelete(ep); err != nil {
-		logrus.Warnf("Failed to remove bridge endpoint %s from store: %v", ep.id[0:7], err)
+		logrus.Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
 	}
 
 	return nil
@@ -1290,7 +1290,7 @@ func (d *driver) ProgramExternalConnectivity(nid, eid string, options map[string
 	}()
 
 	if err = d.storeUpdate(endpoint); err != nil {
-		return fmt.Errorf("failed to update bridge endpoint %s to store: %v", endpoint.id[0:7], err)
+		return fmt.Errorf("failed to update bridge endpoint %.7s to store: %v", endpoint.id, err)
 	}
 
 	if !network.config.EnableICC {
@@ -1332,7 +1332,7 @@ func (d *driver) RevokeExternalConnectivity(nid, eid string) error {
 	clearEndpointConnections(d.nlh, endpoint)
 
 	if err = d.storeUpdate(endpoint); err != nil {
-		return fmt.Errorf("failed to update bridge endpoint %s to store: %v", endpoint.id[0:7], err)
+		return fmt.Errorf("failed to update bridge endpoint %.7s to store: %v", endpoint.id, err)
 	}
 
 	return nil

drivers/bridge/bridge_store.go

@@ -62,7 +62,7 @@ func (d *driver) populateNetworks() error {
 		if err = d.createNetwork(ncfg); err != nil {
 			logrus.Warnf("could not create bridge network for id %s bridge name %s while booting up from persistent state: %v", ncfg.ID, ncfg.BridgeName, err)
 		}
-		logrus.Debugf("Network (%s) restored", ncfg.ID[0:7])
+		logrus.Debugf("Network (%.7s) restored", ncfg.ID)
 	}
 
 	return nil
@@ -82,16 +82,16 @@ func (d *driver) populateEndpoints() error {
 		ep := kvo.(*bridgeEndpoint)
 		n, ok := d.networks[ep.nid]
 		if !ok {
-			logrus.Debugf("Network (%s) not found for restored bridge endpoint (%s)", ep.nid[0:7], ep.id[0:7])
-			logrus.Debugf("Deleting stale bridge endpoint (%s) from store", ep.id[0:7])
+			logrus.Debugf("Network (%.7s) not found for restored bridge endpoint (%.7s)", ep.nid, ep.id)
+			logrus.Debugf("Deleting stale bridge endpoint (%.7s) from store", ep.id)
 			if err := d.storeDelete(ep); err != nil {
-				logrus.Debugf("Failed to delete stale bridge endpoint (%s) from store", ep.id[0:7])
+				logrus.Debugf("Failed to delete stale bridge endpoint (%.7s) from store", ep.id)
 			}
 			continue
 		}
 		n.endpoints[ep.id] = ep
 		n.restorePortAllocations(ep)
-		logrus.Debugf("Endpoint (%s) restored to network (%s)", ep.id[0:7], ep.nid[0:7])
+		logrus.Debugf("Endpoint (%.7s) restored to network (%.7s)", ep.id, ep.nid)
 	}
 
 	return nil
@@ -382,7 +382,7 @@ func (n *bridgeNetwork) restorePortAllocations(ep *bridgeEndpoint) {
 	ep.extConnConfig.PortBindings = ep.portMapping
 	_, err := n.allocatePorts(ep, n.config.DefaultBindingIP, n.driver.config.EnableUserlandProxy)
 	if err != nil {
-		logrus.Warnf("Failed to reserve existing port mapping for endpoint %s:%v", ep.id[0:7], err)
+		logrus.Warnf("Failed to reserve existing port mapping for endpoint %.7s:%v", ep.id, err)
 	}
 	ep.extConnConfig.PortBindings = tmp
 }

drivers/ipvlan/ipvlan_endpoint.go

@@ -53,7 +53,7 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,
 	}
 
 	if err := d.storeUpdate(ep); err != nil {
-		return fmt.Errorf("failed to save ipvlan endpoint %s to store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to save ipvlan endpoint %.7s to store: %v", ep.id, err)
 	}
 
 	n.addEndpoint(ep)
@@ -82,7 +82,7 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	}
 
 	if err := d.storeDelete(ep); err != nil {
-		logrus.Warnf("Failed to remove ipvlan endpoint %s from store: %v", ep.id[0:7], err)
+		logrus.Warnf("Failed to remove ipvlan endpoint %.7s from store: %v", ep.id, err)
 	}
 	n.deleteEndpoint(ep.id)
 	return nil

drivers/ipvlan/ipvlan_joinleave.go

@@ -117,7 +117,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 		return err
 	}
 	if err = d.storeUpdate(ep); err != nil {
-		return fmt.Errorf("failed to save ipvlan endpoint %s to store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to save ipvlan endpoint %.7s to store: %v", ep.id, err)
 	}
 
 	return nil

drivers/ipvlan/ipvlan_network.go

@@ -156,7 +156,7 @@ func (d *driver) DeleteNetwork(nid string) error {
 		}
 
 		if err := d.storeDelete(ep); err != nil {
-			logrus.Warnf("Failed to remove ipvlan endpoint %s from store: %v", ep.id[0:7], err)
+			logrus.Warnf("Failed to remove ipvlan endpoint %.7s from store: %v", ep.id, err)
 		}
 	}
 	// delete the *network

drivers/ipvlan/ipvlan_store.go

@@ -95,15 +95,15 @@ func (d *driver) populateEndpoints() error {
 		ep := kvo.(*endpoint)
 		n, ok := d.networks[ep.nid]
 		if !ok {
-			logrus.Debugf("Network (%s) not found for restored ipvlan endpoint (%s)", ep.nid[0:7], ep.id[0:7])
-			logrus.Debugf("Deleting stale ipvlan endpoint (%s) from store", ep.id[0:7])
+			logrus.Debugf("Network (%.7s) not found for restored ipvlan endpoint (%.7s)", ep.nid, ep.id)
+			logrus.Debugf("Deleting stale ipvlan endpoint (%.7s) from store", ep.id)
 			if err := d.storeDelete(ep); err != nil {
-				logrus.Debugf("Failed to delete stale ipvlan endpoint (%s) from store", ep.id[0:7])
+				logrus.Debugf("Failed to delete stale ipvlan endpoint (%.7s) from store", ep.id)
 			}
 			continue
 		}
 		n.endpoints[ep.id] = ep
-		logrus.Debugf("Endpoint (%s) restored to network (%s)", ep.id[0:7], ep.nid[0:7])
+		logrus.Debugf("Endpoint (%.7s) restored to network (%.7s)", ep.id, ep.nid)
 	}
 
 	return nil

drivers/macvlan/macvlan_endpoint.go

@@ -58,7 +58,7 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,
 	}
 
 	if err := d.storeUpdate(ep); err != nil {
-		return fmt.Errorf("failed to save macvlan endpoint %s to store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to save macvlan endpoint %.7s to store: %v", ep.id, err)
 	}
 
 	n.addEndpoint(ep)
@@ -87,7 +87,7 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	}
 
 	if err := d.storeDelete(ep); err != nil {
-		logrus.Warnf("Failed to remove macvlan endpoint %s from store: %v", ep.id[0:7], err)
+		logrus.Warnf("Failed to remove macvlan endpoint %.7s from store: %v", ep.id, err)
 	}
 
 	n.deleteEndpoint(ep.id)

drivers/macvlan/macvlan_joinleave.go

@@ -78,7 +78,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 		return err
 	}
 	if err := d.storeUpdate(ep); err != nil {
-		return fmt.Errorf("failed to save macvlan endpoint %s to store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to save macvlan endpoint %.7s to store: %v", ep.id, err)
 	}
 	return nil
 }

drivers/macvlan/macvlan_network.go

@@ -160,7 +160,7 @@ func (d *driver) DeleteNetwork(nid string) error {
 		}
 
 		if err := d.storeDelete(ep); err != nil {
-			logrus.Warnf("Failed to remove macvlan endpoint %s from store: %v", ep.id[0:7], err)
+			logrus.Warnf("Failed to remove macvlan endpoint %.7s from store: %v", ep.id, err)
 		}
 	}
 	// delete the *network

drivers/macvlan/macvlan_store.go

@@ -95,15 +95,15 @@ func (d *driver) populateEndpoints() error {
 		ep := kvo.(*endpoint)
 		n, ok := d.networks[ep.nid]
 		if !ok {
-			logrus.Debugf("Network (%s) not found for restored macvlan endpoint (%s)", ep.nid[0:7], ep.id[0:7])
-			logrus.Debugf("Deleting stale macvlan endpoint (%s) from store", ep.id[0:7])
+			logrus.Debugf("Network (%.7s) not found for restored macvlan endpoint (%.7s)", ep.nid, ep.id)
+			logrus.Debugf("Deleting stale macvlan endpoint (%.7s) from store", ep.id)
 			if err := d.storeDelete(ep); err != nil {
-				logrus.Debugf("Failed to delete stale macvlan endpoint (%s) from store", ep.id[0:7])
+				logrus.Debugf("Failed to delete stale macvlan endpoint (%.7s) from store", ep.id)
 			}
 			continue
 		}
 		n.endpoints[ep.id] = ep
-		logrus.Debugf("Endpoint (%s) restored to network (%s)", ep.id[0:7], ep.nid[0:7])
+		logrus.Debugf("Endpoint (%.7s) restored to network (%.7s)", ep.id, ep.nid)
 	}
 
 	return nil

drivers/overlay/encryption.go

@@ -78,7 +78,7 @@ func (e *encrMap) String() string {
 }
 
 func (d *driver) checkEncryption(nid string, rIP net.IP, vxlanID uint32, isLocal, add bool) error {
-	logrus.Debugf("checkEncryption(%s, %v, %d, %t)", nid[0:7], rIP, vxlanID, isLocal)
+	logrus.Debugf("checkEncryption(%.7s, %v, %d, %t)", nid, rIP, vxlanID, isLocal)
 
 	n := d.network(nid)
 	if n == nil || !n.secure {
@@ -101,7 +101,7 @@ func (d *driver) checkEncryption(nid string, rIP net.IP, vxlanID uint32, isLocal
 			}
 			return false
 		}); err != nil {
-			logrus.Warnf("Failed to retrieve list of participating nodes in overlay network %s: %v", nid[0:5], err)
+			logrus.Warnf("Failed to retrieve list of participating nodes in overlay network %.5s: %v", nid, err)
 		}
 	default:
 		if len(d.network(nid).endpoints) > 0 {

drivers/overlay/joinleave.go

@@ -69,7 +69,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 	ep.ifName = containerIfName
 
 	if err = d.writeEndpointToStore(ep); err != nil {
-		return fmt.Errorf("failed to update overlay endpoint %s to local data store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to update overlay endpoint %.7s to local data store: %v", ep.id, err)
 	}
 
 	// Set the container interface and its peer MTU to 1450 to allow

drivers/overlay/ov_endpoint.go

@@ -90,7 +90,7 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,
 	n.addEndpoint(ep)
 
 	if err := d.writeEndpointToStore(ep); err != nil {
-		return fmt.Errorf("failed to update overlay endpoint %s to local store: %v", ep.id[0:7], err)
+		return fmt.Errorf("failed to update overlay endpoint %.7s to local store: %v", ep.id, err)
 	}
 
 	return nil
@@ -116,7 +116,7 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	n.deleteEndpoint(eid)
 
 	if err := d.deleteEndpointFromStore(ep); err != nil {
-		logrus.Warnf("Failed to delete overlay endpoint %s from local store: %v", ep.id[0:7], err)
+		logrus.Warnf("Failed to delete overlay endpoint %.7s from local store: %v", ep.id, err)
 	}
 
 	if ep.ifName == "" {

drivers/overlay/ov_network.go

@@ -274,7 +274,7 @@ func (d *driver) DeleteNetwork(nid string) error {
 		}
 
 		if err := d.deleteEndpointFromStore(ep); err != nil {
-			logrus.Warnf("Failed to delete overlay endpoint %s from local store: %v", ep.id[0:7], err)
+			logrus.Warnf("Failed to delete overlay endpoint %.7s from local store: %v", ep.id, err)
 		}
 	}
 	// flush the peerDB entries

drivers/overlay/overlay.go

@@ -137,10 +137,10 @@ func (d *driver) restoreEndpoints() error {
 		ep := kvo.(*endpoint)
 		n := d.network(ep.nid)
 		if n == nil {
-			logrus.Debugf("Network (%s) not found for restored endpoint (%s)", ep.nid[0:7], ep.id[0:7])
-			logrus.Debugf("Deleting stale overlay endpoint (%s) from store", ep.id[0:7])
+			logrus.Debugf("Network (%.7s) not found for restored endpoint (%.7s)", ep.nid, ep.id)
+			logrus.Debugf("Deleting stale overlay endpoint (%.7s) from store", ep.id)
 			if err := d.deleteEndpointFromStore(ep); err != nil {
-				logrus.Debugf("Failed to delete stale overlay endpoint (%s) from store", ep.id[0:7])
+				logrus.Debugf("Failed to delete stale overlay endpoint (%.7s) from store", ep.id)
 			}
 			continue
 		}

drivers/windows/overlay/ov_endpoint_windows.go

@@ -80,7 +80,7 @@ func (n *network) removeEndpointWithAddress(addr *net.IPNet) {
 		_, err := hcsshim.HNSEndpointRequest("DELETE", networkEndpoint.profileID, "")
 
 		if err != nil {
-			logrus.Debugf("Failed to delete stale overlay endpoint (%s) from hns", networkEndpoint.id[0:7])
+			logrus.Debugf("Failed to delete stale overlay endpoint (%.7s) from hns", networkEndpoint.id)
 		}
 	}
 }

drivers/windows/windows.go

@@ -415,7 +415,7 @@ func (d *driver) DeleteNetwork(nid string) error {
 	// delele endpoints belong to this network
 	for _, ep := range n.endpoints {
 		if err := d.storeDelete(ep); err != nil {
-			logrus.Warnf("Failed to remove bridge endpoint %s from store: %v", ep.id[0:7], err)
+			logrus.Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
 		}
 	}
 
@@ -704,7 +704,7 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,
 	}
 
 	if err = d.storeUpdate(endpoint); err != nil {
-		logrus.Errorf("Failed to save endpoint %s to store: %v", endpoint.id[0:7], err)
+		logrus.Errorf("Failed to save endpoint %.7s to store: %v", endpoint.id, err)
 	}
 
 	return nil
@@ -731,7 +731,7 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	}
 
 	if err := d.storeDelete(ep); err != nil {
-		logrus.Warnf("Failed to remove bridge endpoint %s from store: %v", ep.id[0:7], err)
+		logrus.Warnf("Failed to remove bridge endpoint %.7s from store: %v", ep.id, err)
 	}
 	return nil
 }

drivers/windows/windows_store.go

@@ -64,7 +64,7 @@ func (d *driver) populateNetworks() error {
 		if err = d.createNetwork(ncfg); err != nil {
 			logrus.Warnf("could not create windows network for id %s hnsid %s while booting up from persistent state: %v", ncfg.ID, ncfg.HnsID, err)
 		}
-		logrus.Debugf("Network  %v (%s) restored", d.name, ncfg.ID[0:7])
+		logrus.Debugf("Network  %v (%.7s) restored", d.name, ncfg.ID)
 	}
 
 	return nil
@@ -87,15 +87,15 @@ func (d *driver) populateEndpoints() error {
 		}
 		n, ok := d.networks[ep.nid]
 		if !ok {
-			logrus.Debugf("Network (%s) not found for restored endpoint (%s)", ep.nid[0:7], ep.id[0:7])
-			logrus.Debugf("Deleting stale endpoint (%s) from store", ep.id[0:7])
+			logrus.Debugf("Network (%.7s) not found for restored endpoint (%.7s)", ep.nid, ep.id)
+			logrus.Debugf("Deleting stale endpoint (%.7s) from store", ep.id)
 			if err := d.storeDelete(ep); err != nil {
-				logrus.Debugf("Failed to delete stale endpoint (%s) from store", ep.id[0:7])
+				logrus.Debugf("Failed to delete stale endpoint (%.7s) from store", ep.id)
 			}
 			continue
 		}
 		n.endpoints[ep.id] = ep
-		logrus.Debugf("Endpoint (%s) restored to network (%s)", ep.id[0:7], ep.nid[0:7])
+		logrus.Debugf("Endpoint (%.7s) restored to network (%.7s)", ep.id, ep.nid)
 	}
 
 	return nil

network.go

@@ -1390,7 +1390,7 @@ func (n *network) addSvcRecords(eID, name, serviceID string, epIP, epIPv6 net.IP
 		return
 	}
 
-	logrus.Debugf("%s (%s).addSvcRecords(%s, %s, %s, %t) %s sid:%s", eID, n.ID()[0:7], name, epIP, epIPv6, ipMapUpdate, method, serviceID)
+	logrus.Debugf("%s (%.7s).addSvcRecords(%s, %s, %s, %t) %s sid:%s", eID, n.ID(), name, epIP, epIPv6, ipMapUpdate, method, serviceID)
 
 	c := n.getController()
 	c.Lock()
@@ -1426,7 +1426,7 @@ func (n *network) deleteSvcRecords(eID, name, serviceID string, epIP net.IP, epI
 		return
 	}
 
-	logrus.Debugf("%s (%s).deleteSvcRecords(%s, %s, %s, %t) %s sid:%s ", eID, n.ID()[0:7], name, epIP, epIPv6, ipMapUpdate, method, serviceID)
+	logrus.Debugf("%s (%.7s).deleteSvcRecords(%s, %s, %s, %t) %s sid:%s ", eID, n.ID(), name, epIP, epIPv6, ipMapUpdate, method, serviceID)
 
 	c := n.getController()
 	c.Lock()

networkdb/cluster.go

@@ -52,7 +52,7 @@ func (l *logWriter) Write(p []byte) (int, error) {
 
 // SetKey adds a new key to the key ring
 func (nDB *NetworkDB) SetKey(key []byte) {
-	logrus.Debugf("Adding key %s", hex.EncodeToString(key)[0:5])
+	logrus.Debugf("Adding key %.5s", hex.EncodeToString(key))
 	nDB.Lock()
 	defer nDB.Unlock()
 	for _, dbKey := range nDB.config.Keys {
@@ -69,7 +69,7 @@ func (nDB *NetworkDB) SetKey(key []byte) {
 // SetPrimaryKey sets the given key as the primary key. This should have
 // been added apriori through SetKey
 func (nDB *NetworkDB) SetPrimaryKey(key []byte) {
-	logrus.Debugf("Primary Key %s", hex.EncodeToString(key)[0:5])
+	logrus.Debugf("Primary Key %.5s", hex.EncodeToString(key))
 	nDB.RLock()
 	defer nDB.RUnlock()
 	for _, dbKey := range nDB.config.Keys {
@@ -85,7 +85,7 @@ func (nDB *NetworkDB) SetPrimaryKey(key []byte) {
 // RemoveKey removes a key from the key ring. The key being removed
 // can't be the primary key
 func (nDB *NetworkDB) RemoveKey(key []byte) {
-	logrus.Debugf("Remove Key %s", hex.EncodeToString(key)[0:5])
+	logrus.Debugf("Remove Key %.5s", hex.EncodeToString(key))
 	nDB.Lock()
 	defer nDB.Unlock()
 	for i, dbKey := range nDB.config.Keys {
@@ -123,7 +123,7 @@ func (nDB *NetworkDB) clusterInit() error {
 	var err error
 	if len(nDB.config.Keys) > 0 {
 		for i, key := range nDB.config.Keys {
-			logrus.Debugf("Encryption key %d: %s", i+1, hex.EncodeToString(key)[0:5])
+			logrus.Debugf("Encryption key %d: %.5s", i+1, hex.EncodeToString(key))
 		}
 		nDB.keyring, err = memberlist.NewKeyring(nDB.config.Keys, nDB.config.Keys[0])
 		if err != nil {

sandbox_store.go

@@ -244,7 +244,7 @@ func (c *controller) sandboxCleanup(activeSandboxes map[string]interface{}) {
 		}
 		sb.osSbox, err = osl.NewSandbox(sb.Key(), create, isRestore)
 		if err != nil {
-			logrus.Errorf("failed to create osl sandbox while trying to restore sandbox %s%s: %v", sb.ID()[0:7], msg, err)
+			logrus.Errorf("failed to create osl sandbox while trying to restore sandbox %.7s%s: %v", sb.ID(), msg, err)
 			continue
 		}