Add GetOOMScore function

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

sys/oom_unix.go

@@ -20,8 +20,10 @@ package sys
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
 	"strconv"
+	"strings"
 
 	"github.com/opencontainers/runc/libcontainer/system"
 )
@@ -45,3 +47,13 @@ func SetOOMScore(pid, score int) error {
 	}
 	return nil
 }
+
+// GetOOMScoreAdj gets the oom score for a process
+func GetOOMScoreAdj(pid int) (int, error) {
+	path := fmt.Sprintf("/proc/%d/oom_score_adj", pid)
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.Atoi(strings.TrimSpace(string(data)))
+}

sys/oom_unix_test.go

@@ -20,12 +20,8 @@ package sys
 
 import (
 	"errors"
-	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
-	"strconv"
-	"strings"
 	"testing"
 	"time"
 
@@ -85,7 +81,7 @@ func adjustOom(adjustment int) (int, error) {
 		return 0, err
 	}
 
-	return readOomScoreAdj(pid)
+	return GetOOMScoreAdj(pid)
 }
 
 func waitForPid(process *os.Process) (int, error) {
@@ -106,17 +102,3 @@ func waitForPid(process *os.Process) (int, error) {
 		return 0, errors.New("process did not start in 10 seconds")
 	}
 }
-
-func readOomScoreAdj(pid int) (int, error) {
-	oomScore, err := ioutil.ReadFile(fmt.Sprintf("/proc/%d/oom_score_adj", pid))
-	if err != nil {
-		return 0, err
-	}
-
-	scoreAsInt, err := strconv.Atoi(strings.TrimSpace(string(oomScore)))
-	if err != nil {
-		return 0, err
-	}
-
-	return scoreAsInt, nil
-}

sys/oom_windows.go

@@ -22,3 +22,10 @@ package sys
 func SetOOMScore(pid, score int) error {
 	return nil
 }
+
+// GetOOMScoreAdj gets the oom score for a process
+//
+// Not implemented on Windows
+func GetOOMScoreAdj(pid int) (int, error) {
+	return 0, nil
+}