Add flag package to limit visibility.

PiperOrigin-RevId: 294297004

31 files changed, 72 insertions, 27 deletions

diff --git a/runsc/BUILD b/runsc/BUILD
index 375241921..02a56657a 100644
--- a/runsc/BUILD
+++ b/runsc/BUILD
@@ -19,6 +19,7 @@ go_binary(
         "//pkg/sentry/platform",
         "//runsc/boot",
         "//runsc/cmd",
+        "//runsc/flag",
         "//runsc/specutils",
         "@com_github_google_subcommands//:go_default_library",
     ],
@@ -54,6 +55,7 @@ go_binary(
         "//pkg/sentry/platform",
         "//runsc/boot",
         "//runsc/cmd",
+        "//runsc/flag",
         "//runsc/specutils",
         "@com_github_google_subcommands//:go_default_library",
     ],
diff --git a/runsc/cmd/BUILD b/runsc/cmd/BUILD
index 09aa46434..2a88b85a9 100644
--- a/runsc/cmd/BUILD
+++ b/runsc/cmd/BUILD
@@ -50,6 +50,7 @@ go_library(
         "//runsc/boot/platforms",
         "//runsc/console",
         "//runsc/container",
+        "//runsc/flag",
         "//runsc/fsgofer",
         "//runsc/fsgofer/filter",
         "//runsc/specutils",
diff --git a/runsc/cmd/boot.go b/runsc/cmd/boot.go
index b40fded5b..0f3da69a0 100644
--- a/runsc/cmd/boot.go
+++ b/runsc/cmd/boot.go
@@ -21,12 +21,12 @@ import (
 	"strings"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/boot/platforms"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/checkpoint.go b/runsc/cmd/checkpoint.go
index d8b3a8573..8a29e521e 100644
--- a/runsc/cmd/checkpoint.go
+++ b/runsc/cmd/checkpoint.go
@@ -20,11 +20,11 @@ import (
 	"path/filepath"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/create.go b/runsc/cmd/create.go
index 1815c93b9..910e97577 100644
--- a/runsc/cmd/create.go
+++ b/runsc/cmd/create.go
@@ -17,10 +17,10 @@ package cmd
 import (
 	"context"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/debug.go b/runsc/cmd/debug.go
index f37415810..79965460e 100644
--- a/runsc/cmd/debug.go
+++ b/runsc/cmd/debug.go
@@ -22,12 +22,12 @@ import (
 	"syscall"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/sentry/control"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Debug implements subcommands.Command for the "debug" command.
diff --git a/runsc/cmd/delete.go b/runsc/cmd/delete.go
index 30d8164b1..0e4863f50 100644
--- a/runsc/cmd/delete.go
+++ b/runsc/cmd/delete.go
@@ -19,11 +19,11 @@ import (
 	"fmt"
 	"os"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Delete implements subcommands.Command for the "delete" command.
diff --git a/runsc/cmd/do.go b/runsc/cmd/do.go
index 9a8a49054..b184bd402 100644
--- a/runsc/cmd/do.go
+++ b/runsc/cmd/do.go
@@ -27,12 +27,12 @@ import (
 	"strings"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/events.go b/runsc/cmd/events.go
index 3972e9224..51f6a98ed 100644
--- a/runsc/cmd/events.go
+++ b/runsc/cmd/events.go
@@ -20,11 +20,11 @@ import (
 	"os"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Events implements subcommands.Command for the "events" command.
diff --git a/runsc/cmd/exec.go b/runsc/cmd/exec.go
index d1e99243b..d9a94903e 100644
--- a/runsc/cmd/exec.go
+++ b/runsc/cmd/exec.go
@@ -27,7 +27,6 @@ import (
 	"syscall"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"gvisor.dev/gvisor/pkg/log"
@@ -37,6 +36,7 @@ import (
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/console"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/gofer.go b/runsc/cmd/gofer.go
index 7df7995f0..6e06f3c0f 100644
--- a/runsc/cmd/gofer.go
+++ b/runsc/cmd/gofer.go
@@ -23,7 +23,6 @@ import (
 	"strings"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"golang.org/x/sys/unix"
@@ -32,6 +31,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/unet"
 	"gvisor.dev/gvisor/runsc/boot"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/fsgofer"
 	"gvisor.dev/gvisor/runsc/fsgofer/filter"
 	"gvisor.dev/gvisor/runsc/specutils"
diff --git a/runsc/cmd/help.go b/runsc/cmd/help.go
index 930e8454f..c7d210140 100644
--- a/runsc/cmd/help.go
+++ b/runsc/cmd/help.go
@@ -18,8 +18,8 @@ import (
 	"context"
 	"fmt"
 
-	"flag"
 	"github.com/google/subcommands"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // NewHelp returns a help command for the given commander.
diff --git a/runsc/cmd/install.go b/runsc/cmd/install.go
index 441c1db0d..2e223e3be 100644
--- a/runsc/cmd/install.go
+++ b/runsc/cmd/install.go
@@ -23,8 +23,8 @@ import (
 	"os"
 	"path"
 
-	"flag"
 	"github.com/google/subcommands"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Install implements subcommands.Command.
diff --git a/runsc/cmd/kill.go b/runsc/cmd/kill.go
index 6c1f197a6..8282ea0e0 100644
--- a/runsc/cmd/kill.go
+++ b/runsc/cmd/kill.go
@@ -21,11 +21,11 @@ import (
 	"strings"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Kill implements subcommands.Command for the "kill" command.
diff --git a/runsc/cmd/list.go b/runsc/cmd/list.go
index dd2d99a6b..d8d906fe3 100644
--- a/runsc/cmd/list.go
+++ b/runsc/cmd/list.go
@@ -22,11 +22,11 @@ import (
 	"text/tabwriter"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // List implements subcommands.Command for the "list" command for the "list" command.
diff --git a/runsc/cmd/pause.go b/runsc/cmd/pause.go
index 9c0e92001..6f95a9837 100644
--- a/runsc/cmd/pause.go
+++ b/runsc/cmd/pause.go
@@ -17,10 +17,10 @@ package cmd
 import (
 	"context"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Pause implements subcommands.Command for the "pause" command.
diff --git a/runsc/cmd/ps.go b/runsc/cmd/ps.go
index 45c644f3f..7fb8041af 100644
--- a/runsc/cmd/ps.go
+++ b/runsc/cmd/ps.go
@@ -18,11 +18,11 @@ import (
 	"context"
 	"fmt"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/sentry/control"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // PS implements subcommands.Command for the "ps" command.
diff --git a/runsc/cmd/restore.go b/runsc/cmd/restore.go
index 7be60cd7d..72584b326 100644
--- a/runsc/cmd/restore.go
+++ b/runsc/cmd/restore.go
@@ -19,10 +19,10 @@ import (
 	"path/filepath"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/resume.go b/runsc/cmd/resume.go
index b2df5c640..61a55a554 100644
--- a/runsc/cmd/resume.go
+++ b/runsc/cmd/resume.go
@@ -17,10 +17,10 @@ package cmd
 import (
 	"context"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Resume implements subcommands.Command for the "resume" command.
diff --git a/runsc/cmd/run.go b/runsc/cmd/run.go
index 33f4bc12b..cf41581ad 100644
--- a/runsc/cmd/run.go
+++ b/runsc/cmd/run.go
@@ -18,10 +18,10 @@ import (
 	"context"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
diff --git a/runsc/cmd/spec.go b/runsc/cmd/spec.go
index 344da13ba..8e2b36e85 100644
--- a/runsc/cmd/spec.go
+++ b/runsc/cmd/spec.go
@@ -20,8 +20,8 @@ import (
 	"os"
 	"path/filepath"
 
-	"flag"
 	"github.com/google/subcommands"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 var specTemplate = []byte(`{
diff --git a/runsc/cmd/start.go b/runsc/cmd/start.go
index 5e9bc53ab..0205fd9f7 100644
--- a/runsc/cmd/start.go
+++ b/runsc/cmd/start.go
@@ -17,10 +17,10 @@ package cmd
 import (
 	"context"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Start implements subcommands.Command for the "start" command.
diff --git a/runsc/cmd/state.go b/runsc/cmd/state.go
index e9f41cbd8..cf2413deb 100644
--- a/runsc/cmd/state.go
+++ b/runsc/cmd/state.go
@@ -19,11 +19,11 @@ import (
 	"encoding/json"
 	"os"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // State implements subcommands.Command for the "state" command.
diff --git a/runsc/cmd/syscalls.go b/runsc/cmd/syscalls.go
index fb6c1ab29..7072547be 100644
--- a/runsc/cmd/syscalls.go
+++ b/runsc/cmd/syscalls.go
@@ -25,9 +25,9 @@ import (
 	"strconv"
 	"text/tabwriter"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 // Syscalls implements subcommands.Command for the "syscalls" command.
diff --git a/runsc/cmd/wait.go b/runsc/cmd/wait.go
index 046489687..29c0a15f0 100644
--- a/runsc/cmd/wait.go
+++ b/runsc/cmd/wait.go
@@ -20,10 +20,10 @@ import (
 	"os"
 	"syscall"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/flag"
 )
 
 const (
diff --git a/runsc/container/test_app/BUILD b/runsc/container/test_app/BUILD
index e200bafd9..0defbd9fc 100644
--- a/runsc/container/test_app/BUILD
+++ b/runsc/container/test_app/BUILD
@@ -13,6 +13,7 @@ go_binary(
     visibility = ["//runsc/container:__pkg__"],
     deps = [
         "//pkg/unet",
+        "//runsc/flag",
         "//runsc/testutil",
         "@com_github_google_subcommands//:go_default_library",
         "@com_github_kr_pty//:go_default_library",
diff --git a/runsc/container/test_app/fds.go b/runsc/container/test_app/fds.go
index a90cc1662..2a146a2c3 100644
--- a/runsc/container/test_app/fds.go
+++ b/runsc/container/test_app/fds.go
@@ -21,9 +21,9 @@ import (
 	"os"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/unet"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/testutil"
 )
 
diff --git a/runsc/container/test_app/test_app.go b/runsc/container/test_app/test_app.go
index a1c8a741a..01c47c79f 100644
--- a/runsc/container/test_app/test_app.go
+++ b/runsc/container/test_app/test_app.go
@@ -30,9 +30,9 @@ import (
 	sys "syscall"
 	"time"
 
-	"flag"
 	"github.com/google/subcommands"
 	"github.com/kr/pty"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/testutil"
 )
 
diff --git a/runsc/flag/BUILD b/runsc/flag/BUILD
new file mode 100644
index 000000000..5cb7604a8
--- /dev/null
+++ b/runsc/flag/BUILD
@@ -0,0 +1,9 @@
+load("//tools:defs.bzl", "go_library")
+
+package(licenses = ["notice"])
+
+go_library(
+    name = "flag",
+    srcs = ["flag.go"],
+    visibility = ["//:sandbox"],
+)
diff --git a/runsc/flag/flag.go b/runsc/flag/flag.go
new file mode 100644
index 000000000..0ca4829d7
--- /dev/null
+++ b/runsc/flag/flag.go
@@ -0,0 +1,33 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package flag
+
+import (
+	"flag"
+)
+
+type FlagSet = flag.FlagSet
+
+var (
+	NewFlagSet  = flag.NewFlagSet
+	String      = flag.String
+	Bool        = flag.Bool
+	Int         = flag.Int
+	Uint        = flag.Uint
+	CommandLine = flag.CommandLine
+	Parse       = flag.Parse
+)
+
+const ContinueOnError = flag.ContinueOnError
diff --git a/runsc/main.go b/runsc/main.go
index c2b0d9a9e..762b0f801 100644
--- a/runsc/main.go
+++ b/runsc/main.go
@@ -28,14 +28,13 @@ import (
 	"syscall"
 	"time"
 
-	"flag"
-
 	"github.com/google/subcommands"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/refs"
 	"gvisor.dev/gvisor/pkg/sentry/platform"
 	"gvisor.dev/gvisor/runsc/boot"
 	"gvisor.dev/gvisor/runsc/cmd"
+	"gvisor.dev/gvisor/runsc/flag"
 	"gvisor.dev/gvisor/runsc/specutils"
 )