Fix problems reported by staticcheck

`staticcheck` is a golang code analysis tool. https://staticcheck.io/

This commit fixes a lot of problems found in our code. Common problems are:
- unnecessary use of fmt.Sprintf
- duplicated imports with different names
- unnecessary check that a key exists before a delete call

There are still a lot of reported problems in the test files but I have
not looked at those.

Signed-off-by: Paul Holzinger <paul.holzinger@web.de>

4 files changed, 4 insertions, 11 deletions

diff --git a/pkg/specgen/generate/config_linux.go b/pkg/specgen/generate/config_linux.go
index e0b039fb7..1290a8eb6 100644
--- a/pkg/specgen/generate/config_linux.go
+++ b/pkg/specgen/generate/config_linux.go
@@ -21,9 +21,6 @@ var (
 	errNotADevice = errors.New("not a device node")
 )
 
-func u32Ptr(i int64) *uint32     { u := uint32(i); return &u }
-func fmPtr(i int64) *os.FileMode { fm := os.FileMode(i); return &fm }
-
 func addPrivilegedDevices(g *generate.Generator) error {
 	hostDevices, err := getDevices("/dev")
 	if err != nil {
diff --git a/pkg/specgen/generate/oci.go b/pkg/specgen/generate/oci.go
index ba68de6fd..7dc32a314 100644
--- a/pkg/specgen/generate/oci.go
+++ b/pkg/specgen/generate/oci.go
@@ -110,7 +110,7 @@ func makeCommand(ctx context.Context, s *specgen.SpecGenerator, img *image.Image
 	// Only use image command if the user did not manually set an
 	// entrypoint.
 	command := s.Command
-	if (command == nil || len(command) == 0) && img != nil && (s.Entrypoint == nil || len(s.Entrypoint) == 0) {
+	if len(command) == 0 && img != nil && len(s.Entrypoint) == 0 {
 		newCmd, err := img.Cmd(ctx)
 		if err != nil {
 			return nil, err
diff --git a/pkg/specgen/generate/storage.go b/pkg/specgen/generate/storage.go
index f523ac5bf..63713726e 100644
--- a/pkg/specgen/generate/storage.go
+++ b/pkg/specgen/generate/storage.go
@@ -124,14 +124,10 @@ func finalizeMounts(ctx context.Context, s *specgen.SpecGenerator, rt *libpod.Ru
 	// named volumes, and vice versa.
 	// We'll delete the conflicts here as we supersede.
 	for dest := range unifiedMounts {
-		if _, ok := baseVolumes[dest]; ok {
-			delete(baseVolumes, dest)
-		}
+		delete(baseVolumes, dest)
 	}
 	for dest := range unifiedVolumes {
-		if _, ok := baseMounts[dest]; ok {
-			delete(baseMounts, dest)
-		}
+		delete(baseMounts, dest)
 	}
 
 	// Supersede volumes-from/image volumes with unified volumes from above.
diff --git a/pkg/specgen/generate/validate.go b/pkg/specgen/generate/validate.go
index f0ab4b994..77cccad3e 100644
--- a/pkg/specgen/generate/validate.go
+++ b/pkg/specgen/generate/validate.go
@@ -48,7 +48,7 @@ func verifyContainerResourcesCgroupV1(s *specgen.SpecGenerator) ([]string, error
 				warnings = append(warnings, "Your kernel does not support memory swappiness capabilities, or the cgroup is not mounted. Memory swappiness discarded.")
 				memory.Swappiness = nil
 			} else {
-				if *memory.Swappiness < 0 || *memory.Swappiness > 100 {
+				if *memory.Swappiness > 100 {
 					return warnings, errors.Errorf("invalid value: %v, valid memory swappiness range is 0-100", *memory.Swappiness)
 				}
 			}