Remove excessive error wrapping

In case os.Open[File], os.Mkdir[All], ioutil.ReadFile and the like
fails, the error message already contains the file name and the
operation that fails, so there is no need to wrap the error with
something like "open %s failed".

While at it

 - replace a few places with os.Open, ioutil.ReadAll with
   ioutil.ReadFile.

 - replace errors.Wrapf with errors.Wrap for cases where there
   are no %-style arguments.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/utils/utils_supported.go b/utils/utils_supported.go
index 885112efb..bcaa2c61a 100644
--- a/utils/utils_supported.go
+++ b/utils/utils_supported.go
@@ -56,7 +56,7 @@ func RunUnderSystemdScope(pid int, slice string, unitName string) error {
 func getCgroupProcess(procFile string) (string, error) {
 	f, err := os.Open(procFile)
 	if err != nil {
-		return "", errors.Wrapf(err, "open file %q", procFile)
+		return "", err
 	}
 	defer f.Close()
 
@@ -104,7 +104,7 @@ func MoveUnderCgroupSubtree(subtree string) error {
 	procFile := "/proc/self/cgroup"
 	f, err := os.Open(procFile)
 	if err != nil {
-		return errors.Wrapf(err, "open file %q", procFile)
+		return err
 	}
 	defer f.Close()