Add comments and fix common lint issues

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

client.go

@@ -449,6 +449,7 @@ func (c *Client) DiffService() diff.Differ {
 	return diffservice.NewDiffServiceFromClient(diffapi.NewDiffClient(c.conn))
 }
 
+// IntrospectionService returns the underlying Introspection Client
 func (c *Client) IntrospectionService() introspectionapi.IntrospectionClient {
 	return introspectionapi.NewIntrospectionClient(c.conn)
 }

cmd/containerd/main.go

@@ -110,7 +110,7 @@ func main() {
 		}
 		serverC <- server
 		if config.Debug.Address != "" {
-			l, err := sys.GetLocalListener(config.Debug.Address, config.Debug.Uid, config.Debug.Gid)
+			l, err := sys.GetLocalListener(config.Debug.Address, config.Debug.UID, config.Debug.GID)
 			if err != nil {
 				return errors.Wrapf(err, "failed to get listener for debug endpoint")
 			}
@@ -124,7 +124,7 @@ func main() {
 			serve(log.WithModule(ctx, "metrics"), l, server.ServeMetrics)
 		}
 
-		l, err := sys.GetLocalListener(address, config.GRPC.Uid, config.GRPC.Gid)
+		l, err := sys.GetLocalListener(address, config.GRPC.UID, config.GRPC.GID)
 		if err != nil {
 			return errors.Wrapf(err, "failed to get listener for main endpoint")
 		}

linux/bundle.go

@@ -70,32 +70,33 @@ type bundle struct {
 	workDir string
 }
 
-type shimOpt func(*bundle, string, *runcopts.RuncOptions) (client.Config, client.ClientOpt)
+// ShimOpt specifies shim options for initialization and connection
+type ShimOpt func(*bundle, string, *runcopts.RuncOptions) (client.Config, client.ClientOpt)
 
-// ShimRemote is a shimOpt for connecting and starting a remote shim
+// ShimRemote is a ShimOpt for connecting and starting a remote shim
-func ShimRemote(shim, daemonAddress, cgroup string, nonewns, debug bool, exitHandler func()) shimOpt {
+func ShimRemote(shim, daemonAddress, cgroup string, nonewns, debug bool, exitHandler func()) ShimOpt {
 	return func(b *bundle, ns string, ropts *runcopts.RuncOptions) (client.Config, client.ClientOpt) {
 		return b.shimConfig(ns, ropts),
 			client.WithStart(shim, b.shimAddress(ns), daemonAddress, cgroup, nonewns, debug, exitHandler)
 	}
 }
 
-// ShimLocal is a shimOpt for using an in process shim implementation
+// ShimLocal is a ShimOpt for using an in process shim implementation
-func ShimLocal(exchange *events.Exchange) shimOpt {
+func ShimLocal(exchange *events.Exchange) ShimOpt {
 	return func(b *bundle, ns string, ropts *runcopts.RuncOptions) (client.Config, client.ClientOpt) {
 		return b.shimConfig(ns, ropts), client.WithLocal(exchange)
 	}
 }
 
-// ShimConnect is a shimOpt for connecting to an existing remote shim
+// ShimConnect is a ShimOpt for connecting to an existing remote shim
-func ShimConnect() shimOpt {
+func ShimConnect() ShimOpt {
 	return func(b *bundle, ns string, ropts *runcopts.RuncOptions) (client.Config, client.ClientOpt) {
 		return b.shimConfig(ns, ropts), client.WithConnect(b.shimAddress(ns))
 	}
 }
 
 // NewShimClient connects to the shim managing the bundle and tasks creating it if needed
-func (b *bundle) NewShimClient(ctx context.Context, namespace string, getClientOpts shimOpt, runcOpts *runcopts.RuncOptions) (*client.Client, error) {
+func (b *bundle) NewShimClient(ctx context.Context, namespace string, getClientOpts ShimOpt, runcOpts *runcopts.RuncOptions) (*client.Client, error) {
 	cfg, opt := getClientOpts(b, namespace, runcOpts)
 	return client.New(ctx, cfg, opt)
 }

metadata/content.go

@@ -566,7 +566,7 @@ func (cs *contentStore) garbageCollect(ctx context.Context) error {
 		return err
 	}
 
-	if err := cs.Store.Walk(ctx, func(info content.Info) error {
+	return cs.Store.Walk(ctx, func(info content.Info) error {
 		if _, ok := seen[info.Digest.String()]; !ok {
 			if err := cs.Store.Delete(ctx, info.Digest); err != nil {
 				return err
@@ -574,9 +574,5 @@ func (cs *contentStore) garbageCollect(ctx context.Context) error {
 			log.G(ctx).WithField("digest", info.Digest).Debug("removed content")
 		}
 		return nil
-	}); err != nil {
+	})
-		return err
-	}
-
-	return nil
 }

plugin/context.go

@@ -61,10 +61,13 @@ type Plugin struct {
 	err      error // will be set if there was an error initializing the plugin
 }
 
+// Err returns the errors during initialization.
+// returns nil if not error was encountered
 func (p *Plugin) Err() error {
 	return p.err
 }
 
+// Instance returns the instance and any initialization error of the plugin
 func (p *Plugin) Instance() (interface{}, error) {
 	return p.instance, p.err
 }
@@ -80,12 +83,14 @@ type PluginSet struct {
 	byTypeAndID map[Type]map[string]*Plugin
 }
 
+// NewPluginSet returns an initialized plugin set
 func NewPluginSet() *PluginSet {
 	return &PluginSet{
 		byTypeAndID: make(map[Type]map[string]*Plugin),
 	}
 }
 
+// Add a plugin to the set
 func (ps *PluginSet) Add(p *Plugin) error {
 	if byID, typeok := ps.byTypeAndID[p.Registration.Type]; !typeok {
 		ps.byTypeAndID[p.Registration.Type] = map[string]*Plugin{
@@ -109,6 +114,7 @@ func (ps *PluginSet) Get(t Type) (interface{}, error) {
 	return nil, errors.Wrapf(errdefs.ErrNotFound, "no plugins registered for %s", t)
 }
 
+// GetAll plugins in the set
 func (i *InitContext) GetAll() []*Plugin {
 	return i.plugins.ordered
 }

runtime/task.go

@@ -7,6 +7,7 @@ import (
 	"github.com/gogo/protobuf/types"
 )
 
+// TaskInfo provides task specific information
 type TaskInfo struct {
 	ID        string
 	Runtime   string
@@ -14,6 +15,7 @@ type TaskInfo struct {
 	Namespace string
 }
 
+// Process is a runtime object for an executing process inside a container
 type Process interface {
 	ID() string
 	// State returns the process state
@@ -30,6 +32,7 @@ type Process interface {
 	Wait(context.Context) (*Exit, error)
 }
 
+// Task is the runtime object for an executing container
 type Task interface {
 	Process
 
@@ -55,27 +58,37 @@ type Task interface {
 	Metrics(context.Context) (interface{}, error)
 }
 
+// ExecOpts provides additional options for additional processes running in a task
 type ExecOpts struct {
 	Spec *types.Any
 	IO   IO
 }
 
+// ConsoleSize of a pty or windows terminal
 type ConsoleSize struct {
 	Width  uint32
 	Height uint32
 }
 
+// Status is the runtime status of a task and/or process
 type Status int
 
 const (
+	// CreatedStatus when a process has been created
 	CreatedStatus Status = iota + 1
+	// RunningStatus when a process is running
 	RunningStatus
+	// StoppedStatus when a process has stopped
 	StoppedStatus
+	// DeletedStatus when a process has been deleted
 	DeletedStatus
+	// PausedStatus when a process is paused
 	PausedStatus
+	// PausingStatus when a process is currently pausing
 	PausingStatus
 )
 
+// State information for a process
 type State struct {
 	// Status is the current status of the container
 	Status Status
@@ -93,6 +106,7 @@ type State struct {
 	Terminal bool
 }
 
+// ProcessInfo holds platform specific process information
 type ProcessInfo struct {
 	// Pid is the process ID
 	Pid uint32

runtime/task_list.go

@@ -9,21 +9,26 @@ import (
 )
 
 var (
+	// ErrTaskNotExists is returned when a task does not exist
 	ErrTaskNotExists = errors.New("task does not exist")
+	// ErrTaskAlreadyExists is returned when a task already exists
 	ErrTaskAlreadyExists = errors.New("task already exists")
 )
 
+// NewTaskList returns a new TaskList
 func NewTaskList() *TaskList {
 	return &TaskList{
 		tasks: make(map[string]map[string]Task),
 	}
 }
 
+// TaskList holds and provides locking around tasks
 type TaskList struct {
 	mu    sync.Mutex
 	tasks map[string]map[string]Task
 }
 
+// Get a task
 func (l *TaskList) Get(ctx context.Context, id string) (Task, error) {
 	l.mu.Lock()
 	defer l.mu.Unlock()
@@ -42,6 +47,7 @@ func (l *TaskList) Get(ctx context.Context, id string) (Task, error) {
 	return t, nil
 }
 
+// GetAll tasks under a namespace
 func (l *TaskList) GetAll(ctx context.Context) ([]Task, error) {
 	namespace, err := namespaces.NamespaceRequired(ctx)
 	if err != nil {
@@ -58,6 +64,7 @@ func (l *TaskList) GetAll(ctx context.Context) ([]Task, error) {
 	return o, nil
 }
 
+// Add a task
 func (l *TaskList) Add(ctx context.Context, t Task) error {
 	namespace, err := namespaces.NamespaceRequired(ctx)
 	if err != nil {
@@ -66,6 +73,7 @@ func (l *TaskList) Add(ctx context.Context, t Task) error {
 	return l.AddWithNamespace(namespace, t)
 }
 
+// AddWithNamespace adds a task with the provided namespace
 func (l *TaskList) AddWithNamespace(namespace string, t Task) error {
 	l.mu.Lock()
 	defer l.mu.Unlock()
@@ -81,6 +89,7 @@ func (l *TaskList) AddWithNamespace(namespace string, t Task) error {
 	return nil
 }
 
+// Delete a task
 func (l *TaskList) Delete(ctx context.Context, t Task) {
 	l.mu.Lock()
 	defer l.mu.Unlock()

server/config.go

@@ -36,15 +36,15 @@ type Config struct {
 // GRPCConfig provides GRPC configuration for the socket
 type GRPCConfig struct {
 	Address string `toml:"address"`
-	Uid     int    `toml:"uid"`
+	UID     int    `toml:"uid"`
-	Gid     int    `toml:"gid"`
+	GID     int    `toml:"gid"`
 }
 
 // Debug provides debug configuration
 type Debug struct {
 	Address string `toml:"address"`
-	Uid     int    `toml:"uid"`
+	UID     int    `toml:"uid"`
-	Gid     int    `toml:"gid"`
+	GID     int    `toml:"gid"`
 	Level   string `toml:"level"`
 }
 

services/healthcheck/service.go

@@ -17,13 +17,12 @@ func init() {
 		Type: plugin.GRPCPlugin,
 		ID:   "healthcheck",
 		InitFn: func(*plugin.InitContext) (interface{}, error) {
-			return NewService()
+			return newService()
 		},
 	})
 }
 
-// NewService returns the GRPC health server
+func newService() (*service, error) {
-func NewService() (*service, error) {
 	return &service{
 		health.NewServer(),
 	}, nil

snapshot/btrfs/btrfs.go

@@ -107,8 +107,8 @@ func (b *snapshotter) Stat(ctx context.Context, key string) (snapshot.Info, erro
 	return info, nil
 }
 
-func (o *snapshotter) Update(ctx context.Context, info snapshot.Info, fieldpaths ...string) (snapshot.Info, error) {
+func (b *snapshotter) Update(ctx context.Context, info snapshot.Info, fieldpaths ...string) (snapshot.Info, error) {
-	ctx, t, err := o.ms.TransactionContext(ctx, true)
+	ctx, t, err := b.ms.TransactionContext(ctx, true)
 	if err != nil {
 		return snapshot.Info{}, err
 	}

snapshot/btrfs/btrfs_test.go

@@ -46,12 +46,10 @@ func boltSnapshotter(t *testing.T) func(context.Context, string) (snapshot.Snaps
 			return nil, nil, errors.Wrap(err, "failed to create new snapshotter")
 		}
 
-		return snapshotter, func() (err error) {
+		return snapshotter, func() error {
-			merr := mount.UnmountAll(root, unix.MNT_DETACH)
+			err := mount.UnmountAll(root, unix.MNT_DETACH)
-			if err = cleanupDevice(); err != nil {
+			if cerr := cleanupDevice(); cerr != nil {
-				return errors.Wrap(err, "device cleanup failed")
+				err = errors.Wrap(cerr, "device cleanup failed")
-			} else {
-				err = merr
 			}
 			return err
 		}, nil

snapshot/overlay/overlay.go

@@ -57,7 +57,7 @@ func NewSnapshotter(root string) (snapshot.Snapshotter, error) {
 		return nil, err
 	}
 	if !supportsDType {
-		return nil, fmt.Errorf("%s does not support d_type. If the backing filesystem is xfs, please reformat with ftype=1 to enable d_type support.", root)
+		return nil, fmt.Errorf("%s does not support d_type. If the backing filesystem is xfs, please reformat with ftype=1 to enable d_type support", root)
 	}
 	ms, err := storage.NewMetaStore(filepath.Join(root, "metadata.db"))
 	if err != nil {

snapshot/storage/bolt.go

@@ -582,7 +582,7 @@ func encodeSize(size int64) ([]byte, error) {
 func encodeID(id uint64) ([]byte, error) {
 	var (
 		buf       [binary.MaxVarintLen64]byte
-		idEncoded []byte = buf[:]
+		idEncoded = buf[:]
 	)
 	idEncoded = idEncoded[:binary.PutUvarint(idEncoded, id)]
 

task.go

@@ -51,6 +51,7 @@ type Status struct {
 	ExitTime time.Time
 }
 
+// ProcessInfo provides platform specific process information
 type ProcessInfo struct {
 	// Pid is the process ID
 	Pid uint32

testutil/loopback_linux.go

@@ -46,10 +46,7 @@ func NewLoopback(size int64) (string, func() error, error) {
 
 		// remove file
 		logrus.Debugf("Removing temporary file %s", file.Name())
-		if err = os.Remove(file.Name()); err != nil {
+		return os.Remove(file.Name())
-			return err
-		}
-		return nil
 	}
 
 	return deviceName, cleanup, nil