Remove all instances of named return "err" from Libpod

This was inspired by https://github.com/cri-o/cri-o/pull/3934 and
much of the logic for it is contained there. However, in brief,
a named return called "err" can cause lots of code confusion and
encourages using the wrong err variable in defer statements,
which can make them work incorrectly. Using a separate name which
is not used elsewhere makes it very clear what the defer should
be doing.

As part of this, remove a large number of named returns that were
not used anywhere. Most of them were once needed, but are no
longer necessary after previous refactors (but were accidentally
retained).

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

1 files changed, 10 insertions, 10 deletions

diff --git a/libpod/container_exec.go b/libpod/container_exec.go
index 69da6fcfe..bd04ee9b9 100644
--- a/libpod/container_exec.go
+++ b/libpod/container_exec.go
@@ -779,25 +779,25 @@ func (c *Container) execOCILog(sessionID string) string {
 }
 
 // create a bundle path and associated files for an exec session
-func (c *Container) createExecBundle(sessionID string) (err error) {
+func (c *Container) createExecBundle(sessionID string) (retErr error) {
 	bundlePath := c.execBundlePath(sessionID)
-	if createErr := os.MkdirAll(bundlePath, execDirPermission); createErr != nil {
-		return createErr
+	if err := os.MkdirAll(bundlePath, execDirPermission); err != nil {
+		return err
 	}
 	defer func() {
-		if err != nil {
-			if err2 := os.RemoveAll(bundlePath); err != nil {
-				logrus.Warnf("error removing exec bundle after creation caused another error: %v", err2)
+		if retErr != nil {
+			if err := os.RemoveAll(bundlePath); err != nil {
+				logrus.Warnf("error removing exec bundle after creation caused another error: %v", err)
 			}
 		}
 	}()
-	if err2 := os.MkdirAll(c.execExitFileDir(sessionID), execDirPermission); err2 != nil {
+	if err := os.MkdirAll(c.execExitFileDir(sessionID), execDirPermission); err != nil {
 		// The directory is allowed to exist
-		if !os.IsExist(err2) {
-			err = errors.Wrapf(err2, "error creating OCI runtime exit file path %s", c.execExitFileDir(sessionID))
+		if !os.IsExist(err) {
+			return errors.Wrapf(err, "error creating OCI runtime exit file path %s", c.execExitFileDir(sessionID))
 		}
 	}
-	return
+	return nil
 }
 
 // readExecExitCode reads the exit file for an exec session and returns