Merge pull request #1621 from kolyshkin/govet

ci: enable govet and gosimple linters, fix found bugs

.golangci.yml

@@ -6,6 +6,4 @@ run:
 linters:
   disable:
     - errcheck
-    - gosimple
-    - govet
     - staticcheck

drivers/overlay/overlay.go

@@ -181,7 +181,7 @@ func getMountProgramFlagFile(path string) string {
 }
 
 func checkSupportVolatile(home, runhome string) (bool, error) {
-	feature := fmt.Sprintf("volatile")
+	const feature = "volatile"
 	volatileCacheResult, _, err := cachedFeatureCheck(runhome, feature)
 	var usingVolatile bool
 	if err == nil {

pkg/devicemapper/devmapper.go

@@ -345,8 +345,7 @@ func RemoveDeviceDeferred(name string) error {
 	// disable udev dm rules and delete the symlink under /dev/mapper by itself,
 	// even if the removal is deferred by the kernel.
 	cookie := new(uint)
-	var flags uint16
-	flags = DmUdevDisableLibraryFallback
+	flags := uint16(DmUdevDisableLibraryFallback)
 	if err := task.setCookie(cookie, flags); err != nil {
 		return fmt.Errorf("devicemapper: Can not set cookie: %s", err)
 	}
@@ -384,7 +383,7 @@ func CancelDeferredRemove(deviceName string) error {
 		return fmt.Errorf("devicemapper: Can't set sector %s", err)
 	}
 
-	if err := task.setMessage(fmt.Sprintf("@cancel_deferred_remove")); err != nil {
+	if err := task.setMessage("@cancel_deferred_remove"); err != nil {
 		return fmt.Errorf("devicemapper: Can't set message %s", err)
 	}
 
@@ -459,8 +458,7 @@ func CreatePool(poolName string, dataFile, metadataFile *os.File, poolBlockSize
 	}
 
 	cookie := new(uint)
-	var flags uint16
-	flags = DmUdevDisableSubsystemRulesFlag | DmUdevDisableDiskRulesFlag | DmUdevDisableOtherRulesFlag
+	flags := uint16(DmUdevDisableSubsystemRulesFlag | DmUdevDisableDiskRulesFlag | DmUdevDisableOtherRulesFlag)
 	if err := task.setCookie(cookie, flags); err != nil {
 		return fmt.Errorf("devicemapper: Can't set cookie %s", err)
 	}

pkg/devicemapper/devmapper_wrapper.go

@@ -156,12 +156,11 @@ func dmTaskGetDepsFct(task *cdmTask) *Deps {
 	}
 
 	// golang issue: https://github.com/golang/go/issues/11925
-	hdr := reflect.SliceHeader{
-		Data: uintptr(unsafe.Pointer(uintptr(unsafe.Pointer(Cdeps)) + unsafe.Sizeof(*Cdeps))),
-		Len:  int(Cdeps.count),
-		Cap:  int(Cdeps.count),
-	}
-	devices := *(*[]C.uint64_t)(unsafe.Pointer(&hdr))
+	var devices []C.uint64_t
+	devicesHdr := (*reflect.SliceHeader)(unsafe.Pointer(&devices))
+	devicesHdr.Data = uintptr(unsafe.Pointer(uintptr(unsafe.Pointer(Cdeps)) + unsafe.Sizeof(*Cdeps)))
+	devicesHdr.Len = int(Cdeps.count)
+	devicesHdr.Cap = int(Cdeps.count)
 
 	deps := &Deps{
 		Count:  uint32(Cdeps.count),

pkg/ioutils/readers_test.go

@@ -79,7 +79,8 @@ func (p *perpetualReader) Read(buf []byte) (n int, err error) {
 }
 
 func TestCancelReadCloser(t *testing.T) {
-	ctx, _ := context.WithTimeout(context.Background(), 100*time.Millisecond)
+	ctx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
+	defer cancel()
 	cancelReadCloser := NewCancelReadCloser(ctx, io.NopCloser(&perpetualReader{}))
 	for {
 		var buf [128]byte

pkg/regexp/regexp.go

@@ -11,7 +11,7 @@ import (
 // of apps that want to use global regex variables. This library initializes them on
 // first use as opposed to the start of the executable.
 type Regexp struct {
-	once   sync.Once
+	once   *sync.Once
 	regexp *regexp.Regexp
 	val    string
 }
@@ -22,7 +22,10 @@ func Delayed(val string) Regexp {
 	}
 	if precompile {
 		re.regexp = regexp.MustCompile(re.val)
+	} else {
+		re.once = &sync.Once{}
 	}
+
 	return re
 }