Merge pull request #933 from zhaoleidd/workaround_for_ps

cli: Workaround for ps's argument

man/runc-ps.8.md

@@ -2,7 +2,7 @@
    runc ps - ps displays the processes running inside a container
 
 # SYNOPSIS
-   runc ps [command options] <container-id> [ps options]
+   runc ps [command options] <container-id> [-- ps options]
 
 # OPTIONS
    --format value, -f value     select one of: table(default) or json

ps.go

@@ -16,7 +16,7 @@ import (
 var psCommand = cli.Command{
 	Name:      "ps",
 	Usage:     "ps displays the processes running inside a container",
-	ArgsUsage: `<container-id> [ps options]`,
+	ArgsUsage: `<container-id> [-- ps options]`,
 	Flags: []cli.Flag{
 		cli.StringFlag{
 			Name:  "format, f",
@@ -42,12 +42,21 @@ var psCommand = cli.Command{
 			return nil
 		}
 
-		psArgs := context.Args().Get(1)
-		if psArgs == "" {
-			psArgs = "-ef"
+		// [1:] is to remove command name, ex:
+		// context.Args(): [containet_id ps_arg1 ps_arg2 ...]
+		// psArgs:         [ps_arg1 ps_arg2 ...]
+		//
+		psArgs := context.Args()[1:]
+
+		if len(psArgs) > 0 && psArgs[0] == "--" {
+			psArgs = psArgs[1:]
 		}
 
-		output, err := exec.Command("ps", strings.Split(psArgs, " ")...).Output()
+		if len(psArgs) == 0 {
+			psArgs = []string{"-ef"}
+		}
+
+		output, err := exec.Command("ps", psArgs...).Output()
 		if err != nil {
 			return err
 		}