make lint: enable gocritic

`gocritic` is a powerful linter that helps in preventing certain kinds
of errors as well as enforcing a coding style.

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

9 files changed, 64 insertions, 53 deletions

diff --git a/pkg/adapter/containers.go b/pkg/adapter/containers.go
index fdd9f6ab3..4e6bcfaa7 100644
--- a/pkg/adapter/containers.go
+++ b/pkg/adapter/containers.go
@@ -609,11 +609,12 @@ func (r *LocalRuntime) Restore(ctx context.Context, c *cliconfig.RestoreValues)
 		return state == define.ContainerStateExited
 	})
 
-	if c.Import != "" {
+	switch {
+	case c.Import != "":
 		containers, err = crImportCheckpoint(ctx, r.Runtime, c.Import, c.Name)
-	} else if c.All {
+	case c.All:
 		containers, err = r.GetContainers(filterFuncs...)
-	} else {
+	default:
 		containers, err = shortcuts.GetContainersByContext(false, c.Latest, c.InputArgs, r.Runtime)
 	}
 	if err != nil {
@@ -835,25 +836,26 @@ func (r *LocalRuntime) Restart(ctx context.Context, c *cliconfig.RestartValues)
 	inputTimeout := c.Timeout
 
 	// Handle --latest
-	if c.Latest {
+	switch {
+	case c.Latest:
 		lastCtr, err := r.Runtime.GetLatestContainer()
 		if err != nil {
 			return nil, nil, errors.Wrapf(err, "unable to get latest container")
 		}
 		restartContainers = append(restartContainers, lastCtr)
-	} else if c.Running {
+	case c.Running:
 		containers, err = r.GetRunningContainers()
 		if err != nil {
 			return nil, nil, err
 		}
 		restartContainers = append(restartContainers, containers...)
-	} else if c.All {
+	case c.All:
 		containers, err = r.Runtime.GetAllContainers()
 		if err != nil {
 			return nil, nil, err
 		}
 		restartContainers = append(restartContainers, containers...)
-	} else {
+	default:
 		for _, id := range c.InputArgs {
 			ctr, err := r.Runtime.LookupContainer(id)
 			if err != nil {
diff --git a/pkg/adapter/runtime.go b/pkg/adapter/runtime.go
index 5f880e807..3be65a03e 100644
--- a/pkg/adapter/runtime.go
+++ b/pkg/adapter/runtime.go
@@ -407,7 +407,8 @@ func (r *LocalRuntime) Events(c *cliconfig.EventValues) error {
 	}
 	w := bufio.NewWriter(os.Stdout)
 	for event := range eventChannel {
-		if c.Format == formats.JSONString {
+		switch {
+		case c.Format == formats.JSONString:
 			jsonStr, err := event.ToJSONString()
 			if err != nil {
 				return errors.Wrapf(err, "unable to format json")
@@ -415,11 +416,11 @@ func (r *LocalRuntime) Events(c *cliconfig.EventValues) error {
 			if _, err := w.Write([]byte(jsonStr)); err != nil {
 				return err
 			}
-		} else if len(c.Format) > 0 {
+		case len(c.Format) > 0:
 			if err := tmpl.Execute(w, event); err != nil {
 				return err
 			}
-		} else {
+		default:
 			if _, err := w.Write([]byte(event.ToHumanReadable())); err != nil {
 				return err
 			}
diff --git a/pkg/adapter/shortcuts/shortcuts.go b/pkg/adapter/shortcuts/shortcuts.go
index 4f6cfd6a3..8a8459c6c 100644
--- a/pkg/adapter/shortcuts/shortcuts.go
+++ b/pkg/adapter/shortcuts/shortcuts.go
@@ -42,12 +42,13 @@ func GetContainersByContext(all, latest bool, names []string, runtime *libpod.Ru
 	var ctr *libpod.Container
 	ctrs = []*libpod.Container{}
 
-	if all {
+	switch {
+	case all:
 		ctrs, err = runtime.GetAllContainers()
-	} else if latest {
+	case latest:
 		ctr, err = runtime.GetLatestContainer()
 		ctrs = append(ctrs, ctr)
-	} else {
+	default:
 		for _, n := range names {
 			ctr, e := runtime.LookupContainer(n)
 			if e != nil {
diff --git a/pkg/api/handlers/utils/handler.go b/pkg/api/handlers/utils/handler.go
index 0815e6eca..8c2110f97 100644
--- a/pkg/api/handlers/utils/handler.go
+++ b/pkg/api/handlers/utils/handler.go
@@ -12,19 +12,19 @@ import (
 
 // WriteResponse encodes the given value as JSON or string and renders it for http client
 func WriteResponse(w http.ResponseWriter, code int, value interface{}) {
-	switch value.(type) {
+	switch v := value.(type) {
 	case string:
 		w.Header().Set("Content-Type", "text/plain; charset=us-ascii")
 		w.WriteHeader(code)
 
-		if _, err := fmt.Fprintln(w, value); err != nil {
+		if _, err := fmt.Fprintln(w, v); err != nil {
 			log.Errorf("unable to send string response: %q", err)
 		}
 	case *os.File:
 		w.Header().Set("Content-Type", "application/octet; charset=us-ascii")
 		w.WriteHeader(code)
 
-		if _, err := io.Copy(w, value.(*os.File)); err != nil {
+		if _, err := io.Copy(w, v); err != nil {
 			log.Errorf("unable to copy to response: %q", err)
 		}
 	default:
diff --git a/pkg/cgroups/cgroups.go b/pkg/cgroups/cgroups.go
index 9711e8120..6b28b2759 100644
--- a/pkg/cgroups/cgroups.go
+++ b/pkg/cgroups/cgroups.go
@@ -155,7 +155,7 @@ func (c *CgroupControl) getCgroupv1Path(name string) string {
 }
 
 // createCgroupv2Path creates the cgroupv2 path and enables all the available controllers
-func createCgroupv2Path(path string) (Err error) {
+func createCgroupv2Path(path string) (deferredError error) {
 	content, err := ioutil.ReadFile("/sys/fs/cgroup/cgroup.controllers")
 	if err != nil {
 		return errors.Wrapf(err, "read /sys/fs/cgroup/cgroup.controllers")
@@ -169,7 +169,7 @@ func createCgroupv2Path(path string) (Err error) {
 		if i == 0 {
 			res = fmt.Sprintf("+%s", c)
 		} else {
-			res = res + fmt.Sprintf(" +%s", c)
+			res += fmt.Sprintf(" +%s", c)
 		}
 	}
 	resByte := []byte(res)
@@ -186,7 +186,7 @@ func createCgroupv2Path(path string) (Err error) {
 			} else {
 				// If the directory was created, be sure it is not left around on errors.
 				defer func() {
-					if Err != nil {
+					if deferredError != nil {
 						os.Remove(current)
 					}
 				}()
diff --git a/pkg/spec/namespaces.go b/pkg/spec/namespaces.go
index 8e95a3ca0..e62d4ed0a 100644
--- a/pkg/spec/namespaces.go
+++ b/pkg/spec/namespaces.go
@@ -44,7 +44,8 @@ func (c *NetworkConfig) ToCreateOptions(runtime *libpod.Runtime, userns *UserCon
 		}
 	}
 
-	if c.NetMode.IsNS() {
+	switch {
+	case c.NetMode.IsNS():
 		ns := c.NetMode.NS()
 		if ns == "" {
 			return nil, errors.Errorf("invalid empty user-defined network namespace")
@@ -53,13 +54,13 @@ func (c *NetworkConfig) ToCreateOptions(runtime *libpod.Runtime, userns *UserCon
 		if err != nil {
 			return nil, err
 		}
-	} else if c.NetMode.IsContainer() {
+	case c.NetMode.IsContainer():
 		connectedCtr, err := runtime.LookupContainer(c.NetMode.Container())
 		if err != nil {
 			return nil, errors.Wrapf(err, "container %q not found", c.NetMode.Container())
 		}
 		options = append(options, libpod.WithNetNSFrom(connectedCtr))
-	} else if !c.NetMode.IsHost() && !c.NetMode.IsNone() {
+	case !c.NetMode.IsHost() && !c.NetMode.IsNone():
 		postConfigureNetNS := userns.getPostConfigureNetNS()
 		options = append(options, libpod.WithNetNS(portBindings, postConfigureNetNS, string(c.NetMode), networks))
 	}
@@ -102,29 +103,31 @@ func (c *NetworkConfig) ToCreateOptions(runtime *libpod.Runtime, userns *UserCon
 // state of the NetworkConfig.
 func (c *NetworkConfig) ConfigureGenerator(g *generate.Generator) error {
 	netMode := c.NetMode
-	if netMode.IsHost() {
+	netCtr := netMode.Container()
+	switch {
+	case netMode.IsHost():
 		logrus.Debug("Using host netmode")
 		if err := g.RemoveLinuxNamespace(string(spec.NetworkNamespace)); err != nil {
 			return err
 		}
-	} else if netMode.IsNone() {
+	case netMode.IsNone():
 		logrus.Debug("Using none netmode")
-	} else if netMode.IsBridge() {
+	case netMode.IsBridge():
 		logrus.Debug("Using bridge netmode")
-	} else if netCtr := netMode.Container(); netCtr != "" {
+	case netCtr != "":
 		logrus.Debugf("using container %s netmode", netCtr)
-	} else if IsNS(string(netMode)) {
+	case IsNS(string(netMode)):
 		logrus.Debug("Using ns netmode")
 		if err := g.AddOrReplaceLinuxNamespace(string(spec.NetworkNamespace), NS(string(netMode))); err != nil {
 			return err
 		}
-	} else if IsPod(string(netMode)) {
+	case IsPod(string(netMode)):
 		logrus.Debug("Using pod netmode, unless pod is not sharing")
-	} else if netMode.IsSlirp4netns() {
+	case netMode.IsSlirp4netns():
 		logrus.Debug("Using slirp4netns netmode")
-	} else if netMode.IsUserDefined() {
+	case netMode.IsUserDefined():
 		logrus.Debug("Using user defined netmode")
-	} else {
+	default:
 		return errors.Errorf("unknown network mode")
 	}
 
@@ -220,7 +223,8 @@ func (c *CgroupConfig) ToCreateOptions(runtime *libpod.Runtime) ([]libpod.CtrCre
 // ToCreateOptions converts the input to container create options.
 func (c *UserConfig) ToCreateOptions(runtime *libpod.Runtime) ([]libpod.CtrCreateOption, error) {
 	options := make([]libpod.CtrCreateOption, 0)
-	if c.UsernsMode.IsNS() {
+	switch {
+	case c.UsernsMode.IsNS():
 		ns := c.UsernsMode.NS()
 		if ns == "" {
 			return nil, errors.Errorf("invalid empty user-defined user namespace")
@@ -230,13 +234,13 @@ func (c *UserConfig) ToCreateOptions(runtime *libpod.Runtime) ([]libpod.CtrCreat
 			return nil, err
 		}
 		options = append(options, libpod.WithIDMappings(*c.IDMappings))
-	} else if c.UsernsMode.IsContainer() {
+	case c.UsernsMode.IsContainer():
 		connectedCtr, err := runtime.LookupContainer(c.UsernsMode.Container())
 		if err != nil {
 			return nil, errors.Wrapf(err, "container %q not found", c.UsernsMode.Container())
 		}
 		options = append(options, libpod.WithUserNSFrom(connectedCtr))
-	} else {
+	default:
 		options = append(options, libpod.WithIDMappings(*c.IDMappings))
 	}
 
@@ -413,20 +417,22 @@ func (c *UtsConfig) ToCreateOptions(runtime *libpod.Runtime, pod *libpod.Pod) ([
 // of the UtsConfig.
 func (c *UtsConfig) ConfigureGenerator(g *generate.Generator, net *NetworkConfig, runtime *libpod.Runtime) error {
 	hostname := c.Hostname
+	utsCtrID := c.UtsMode.Container()
 	var err error
 	if hostname == "" {
-		if utsCtrID := c.UtsMode.Container(); utsCtrID != "" {
+		switch {
+		case utsCtrID != "":
 			utsCtr, err := runtime.GetContainer(utsCtrID)
 			if err != nil {
 				return errors.Wrapf(err, "unable to retrieve hostname from dependency container %s", utsCtrID)
 			}
 			hostname = utsCtr.Hostname()
-		} else if net.NetMode.IsHost() || c.UtsMode.IsHost() {
+		case net.NetMode.IsHost() || c.UtsMode.IsHost():
 			hostname, err = os.Hostname()
 			if err != nil {
 				return errors.Wrap(err, "unable to retrieve hostname of the host")
 			}
-		} else {
+		default:
 			logrus.Debug("No hostname set; container's hostname will default to runtime default")
 		}
 	}
diff --git a/pkg/spec/storage.go b/pkg/spec/storage.go
index dbdab0030..0e2098c1d 100644
--- a/pkg/spec/storage.go
+++ b/pkg/spec/storage.go
@@ -409,9 +409,10 @@ func getBindMount(args []string) (spec.Mount, error) {
 			// ro=[true|false]
 			// rw
 			// rw=[true|false]
-			if len(kv) == 1 {
+			switch len(kv) {
+			case 1:
 				newMount.Options = append(newMount.Options, kv[0])
-			} else if len(kv) == 2 {
+			case 2:
 				switch strings.ToLower(kv[1]) {
 				case "true":
 					newMount.Options = append(newMount.Options, kv[0])
@@ -424,7 +425,7 @@ func getBindMount(args []string) (spec.Mount, error) {
 				default:
 					return newMount, errors.Wrapf(optionArgError, "%s must be set to true or false, instead received %q", kv[0], kv[1])
 				}
-			} else {
+			default:
 				return newMount, errors.Wrapf(optionArgError, "badly formatted option %q", val)
 			}
 		case "nosuid", "suid":
diff --git a/pkg/timetype/timestamp.go b/pkg/timetype/timestamp.go
index eb904a574..2de1a005f 100644
--- a/pkg/timetype/timestamp.go
+++ b/pkg/timetype/timestamp.go
@@ -34,7 +34,7 @@ func GetTimestamp(value string, reference time.Time) (string, error) {
 	// if the string has a Z or a + or three dashes use parse otherwise use parseinlocation
 	parseInLocation := !(strings.ContainsAny(value, "zZ+") || strings.Count(value, "-") == 3)
 
-	if strings.Contains(value, ".") {
+	if strings.Contains(value, ".") { // nolint(gocritic)
 		if parseInLocation {
 			format = rFC3339NanoLocal
 		} else {
diff --git a/pkg/util/utils.go b/pkg/util/utils.go
index 9269f6115..6aa3c221e 100644
--- a/pkg/util/utils.go
+++ b/pkg/util/utils.go
@@ -321,14 +321,14 @@ func ParseSignal(rawSignal string) (syscall.Signal, error) {
 }
 
 // ParseIDMapping takes idmappings and subuid and subgid maps and returns a storage mapping
-func ParseIDMapping(mode namespaces.UsernsMode, UIDMapSlice, GIDMapSlice []string, subUIDMap, subGIDMap string) (*storage.IDMappingOptions, error) {
+func ParseIDMapping(mode namespaces.UsernsMode, uidMapSlice, gidMapSlice []string, subUIDMap, subGIDMap string) (*storage.IDMappingOptions, error) {
 	options := storage.IDMappingOptions{
 		HostUIDMapping: true,
 		HostGIDMapping: true,
 	}
 
 	if mode.IsKeepID() {
-		if len(UIDMapSlice) > 0 || len(GIDMapSlice) > 0 {
+		if len(uidMapSlice) > 0 || len(gidMapSlice) > 0 {
 			return nil, errors.New("cannot specify custom mappings with --userns=keep-id")
 		}
 		if len(subUIDMap) > 0 || len(subGIDMap) > 0 {
@@ -384,17 +384,17 @@ func ParseIDMapping(mode namespaces.UsernsMode, UIDMapSlice, GIDMapSlice []strin
 	if subUIDMap == "" && subGIDMap != "" {
 		subUIDMap = subGIDMap
 	}
-	if len(GIDMapSlice) == 0 && len(UIDMapSlice) != 0 {
-		GIDMapSlice = UIDMapSlice
+	if len(gidMapSlice) == 0 && len(uidMapSlice) != 0 {
+		gidMapSlice = uidMapSlice
 	}
-	if len(UIDMapSlice) == 0 && len(GIDMapSlice) != 0 {
-		UIDMapSlice = GIDMapSlice
+	if len(uidMapSlice) == 0 && len(gidMapSlice) != 0 {
+		uidMapSlice = gidMapSlice
 	}
-	if len(UIDMapSlice) == 0 && subUIDMap == "" && os.Getuid() != 0 {
-		UIDMapSlice = []string{fmt.Sprintf("0:%d:1", os.Getuid())}
+	if len(uidMapSlice) == 0 && subUIDMap == "" && os.Getuid() != 0 {
+		uidMapSlice = []string{fmt.Sprintf("0:%d:1", os.Getuid())}
 	}
-	if len(GIDMapSlice) == 0 && subGIDMap == "" && os.Getuid() != 0 {
-		GIDMapSlice = []string{fmt.Sprintf("0:%d:1", os.Getgid())}
+	if len(gidMapSlice) == 0 && subGIDMap == "" && os.Getuid() != 0 {
+		gidMapSlice = []string{fmt.Sprintf("0:%d:1", os.Getgid())}
 	}
 
 	if subUIDMap != "" && subGIDMap != "" {
@@ -405,11 +405,11 @@ func ParseIDMapping(mode namespaces.UsernsMode, UIDMapSlice, GIDMapSlice []strin
 		options.UIDMap = mappings.UIDs()
 		options.GIDMap = mappings.GIDs()
 	}
-	parsedUIDMap, err := idtools.ParseIDMap(UIDMapSlice, "UID")
+	parsedUIDMap, err := idtools.ParseIDMap(uidMapSlice, "UID")
 	if err != nil {
 		return nil, err
 	}
-	parsedGIDMap, err := idtools.ParseIDMap(GIDMapSlice, "GID")
+	parsedGIDMap, err := idtools.ParseIDMap(gidMapSlice, "GID")
 	if err != nil {
 		return nil, err
 	}