various cleanups to address linter issues

Signed-off-by: Dominik Süß <dominik@suess.wtf>

checkpoint.go

@@ -71,10 +71,7 @@ checkpointed.`,
 		if err := setEmptyNsMask(context, options); err != nil {
 			return err
 		}
-		if err := container.Checkpoint(options); err != nil {
-			return err
-		}
-		return nil
+		return container.Checkpoint(options)
 	},
 }
 

delete.go

@@ -80,9 +80,8 @@ status of "ubuntu01" as "stopped" the following will delete resources held for
 		default:
 			if force {
 				return killContainer(container)
-			} else {
-				return fmt.Errorf("cannot delete container %s that is not stopped: %s\n", id, s)
 			}
+			return fmt.Errorf("cannot delete container %s that is not stopped: %s\n", id, s)
 		}
 
 		return nil

kill.go

@@ -51,10 +51,7 @@ signal to the init process of the "ubuntu01" container:
 		if err != nil {
 			return err
 		}
-		if err := container.Signal(signal, context.Bool("all")); err != nil {
-			return err
-		}
-		return nil
+		return container.Signal(signal, context.Bool("all"))
 	},
 }
 

libcontainer/cgroups/fs/cpu.go

@@ -46,11 +46,7 @@ func (s *CpuGroup) ApplyDir(path string, cgroup *configs.Cgroup, pid int) error
 	}
 	// because we are not using d.join we need to place the pid into the procs file
 	// unlike the other subsystems
-	if err := cgroups.WriteCgroupProc(path, pid); err != nil {
-		return err
-	}
-
-	return nil
+	return cgroups.WriteCgroupProc(path, pid)
 }
 
 func (s *CpuGroup) SetRtSched(path string, cgroup *configs.Cgroup) error {
@@ -83,11 +79,7 @@ func (s *CpuGroup) Set(path string, cgroup *configs.Cgroup) error {
 			return err
 		}
 	}
-	if err := s.SetRtSched(path, cgroup); err != nil {
-		return err
-	}
-
-	return nil
+	return s.SetRtSched(path, cgroup)
 }
 
 func (s *CpuGroup) Remove(d *cgroupData) error {

libcontainer/cgroups/fs/cpuset.go

@@ -84,11 +84,7 @@ func (s *CpusetGroup) ApplyDir(dir string, cgroup *configs.Cgroup, pid int) erro
 
 	// because we are not using d.join we need to place the pid into the procs file
 	// unlike the other subsystems
-	if err := cgroups.WriteCgroupProc(dir, pid); err != nil {
-		return err
-	}
-
-	return nil
+	return cgroups.WriteCgroupProc(dir, pid)
 }
 
 func (s *CpusetGroup) getSubsystemSettings(parent string) (cpus []byte, mems []byte, err error) {

libcontainer/container_linux.go

@@ -399,10 +399,7 @@ func (c *linuxContainer) createExecFifo() error {
 		return err
 	}
 	unix.Umask(oldMask)
-	if err := os.Chown(fifoName, rootuid, rootgid); err != nil {
-		return err
-	}
-	return nil
+	return os.Chown(fifoName, rootuid, rootgid)
 }
 
 func (c *linuxContainer) deleteExecFifo() {

libcontainer/init_linux.go

@@ -218,11 +218,7 @@ func syncParentReady(pipe io.ReadWriter) error {
 	}
 
 	// Wait for parent to give the all-clear.
-	if err := readSync(pipe, procRun); err != nil {
-		return err
-	}
-
-	return nil
+	return readSync(pipe, procRun)
 }
 
 // syncParentHooks sends to the given pipe a JSON payload which indicates that
@@ -235,11 +231,7 @@ func syncParentHooks(pipe io.ReadWriter) error {
 	}
 
 	// Wait for parent to give the all-clear.
-	if err := readSync(pipe, procResume); err != nil {
-		return err
-	}
-
-	return nil
+	return readSync(pipe, procResume)
 }
 
 // setupUser changes the groups, gid, and uid for the user inside the container

libcontainer/integration/exec_test.go

@@ -1263,10 +1263,7 @@ func TestSTDIOPermissions(t *testing.T) {
 }
 
 func unmountOp(path string) error {
-	if err := unix.Unmount(path, unix.MNT_DETACH); err != nil {
-		return err
-	}
-	return nil
+	return unix.Unmount(path, unix.MNT_DETACH)
 }
 
 // Launch container with rootfsPropagation in rslave mode. Also

libcontainer/keys/keyctl.go

@@ -44,9 +44,5 @@ func ModKeyringPerm(ringId KeySerial, mask, setbits uint32) error {
 
 	perm := (uint32(perm64) & mask) | setbits
 
-	if err := unix.KeyctlSetperm(int(ringId), perm); err != nil {
-		return err
-	}
-
-	return nil
+	return unix.KeyctlSetperm(int(ringId), perm)
 }

libcontainer/rootfs_linux.go

@@ -828,10 +828,7 @@ func remount(m *configs.Mount, rootfs string) error {
 	if !strings.HasPrefix(dest, rootfs) {
 		dest = filepath.Join(rootfs, dest)
 	}
-	if err := unix.Mount(m.Source, dest, m.Device, uintptr(m.Flags|unix.MS_REMOUNT), ""); err != nil {
-		return err
-	}
-	return nil
+	return unix.Mount(m.Source, dest, m.Device, uintptr(m.Flags|unix.MS_REMOUNT), "")
 }
 
 // Do the mount operation followed by additional mounts required to take care

libcontainer/standard_init_linux.go

@@ -52,7 +52,7 @@ func (l *linuxStandardInit) Init() error {
 			// If keyrings aren't supported then it is likely we are on an
 			// older kernel (or inside an LXC container). While we could bail,
 			// the security feature we are using here is best-effort (it only
-			// really provides marignal protection since VFS credentials are
+			// really provides marginal protection since VFS credentials are
 			// the only significant protection of keyrings).
 			//
 			// TODO(cyphar): Log this so people know what's going on, once we

libcontainer/sync.go

@@ -41,10 +41,7 @@ type syncT struct {
 // writeSync is used to write to a synchronisation pipe. An error is returned
 // if there was a problem writing the payload.
 func writeSync(pipe io.Writer, sync syncType) error {
-	if err := utils.WriteJSON(pipe, syncT{sync}); err != nil {
-		return err
-	}
-	return nil
+	return utils.WriteJSON(pipe, syncT{sync})
 }
 
 // readSync is used to read from a synchronisation pipe. An error is returned

notify_socket.go

@@ -37,8 +37,8 @@ func newNotifySocket(context *cli.Context, notifySocketHost string, id string) *
 	return notifySocket
 }
 
-func (ns *notifySocket) Close() error {
-	return ns.socket.Close()
+func (s *notifySocket) Close() error {
+	return s.socket.Close()
 }
 
 // If systemd is supporting sd_notify protocol, this function will add support
@@ -66,16 +66,16 @@ func (s *notifySocket) setupSocket() error {
 
 // pid1 must be set only with -d, as it is used to set the new process as the main process
 // for the service in systemd
-func (notifySocket *notifySocket) run(pid1 int) {
+func (s *notifySocket) run(pid1 int) {
 	buf := make([]byte, 512)
-	notifySocketHostAddr := net.UnixAddr{Name: notifySocket.host, Net: "unixgram"}
+	notifySocketHostAddr := net.UnixAddr{Name: s.host, Net: "unixgram"}
 	client, err := net.DialUnix("unixgram", nil, &notifySocketHostAddr)
 	if err != nil {
 		logrus.Error(err)
 		return
 	}
 	for {
-		r, err := notifySocket.socket.Read(buf)
+		r, err := s.socket.Read(buf)
 		if err != nil {
 			break
 		}

pause.go

@@ -22,11 +22,7 @@ Use runc list to identiy instances of containers and their current status.`,
 		if err != nil {
 			return err
 		}
-		if err := container.Pause(); err != nil {
-			return err
-		}
-
-		return nil
+		return container.Pause()
 	},
 }
 
@@ -48,10 +44,6 @@ Use runc list to identiy instances of containers and their current status.`,
 		if err != nil {
 			return err
 		}
-		if err := container.Resume(); err != nil {
-			return err
-		}
-
-		return nil
+		return container.Resume()
 	},
 }

signals.go

@@ -69,9 +69,8 @@ func (h *signalHandler) forward(process *libcontainer.Process, tty *tty, detach
 		if detach {
 			h.notifySocket.run(pid1)
 			return 0, nil
-		} else {
-			go h.notifySocket.run(0)
 		}
+		go h.notifySocket.run(0)
 	}
 
 	// Perform the initial tty resize. Always ignore errors resizing because

spec.go

@@ -107,10 +107,7 @@ generate a proper rootless spec file.`,
 		if err != nil {
 			return err
 		}
-		if err := ioutil.WriteFile(specConfig, data, 0666); err != nil {
-			return err
-		}
-		return nil
+		return ioutil.WriteFile(specConfig, data, 0666)
 	},
 }