From 273c337a238a2bf09e6dfd2755731f4ed0aab076 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@jakstys.lt>
Date: Mon, 24 May 2021 00:11:57 +0300
Subject: [PATCH] move rootfs, add gofmt

---
 BUILD     |  5 ++++-
 main.go   | 28 +++++++++++-----------------
 rootfs.go | 21 +++++++++++++++++++++
 3 files changed, 36 insertions(+), 18 deletions(-)
 create mode 100644 rootfs.go

diff --git a/BUILD b/BUILD
index bd10e1f..c10f473 100644
--- a/BUILD
+++ b/BUILD
@@ -2,7 +2,10 @@ load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
 
 go_library(
     name = "undocker_lib",
-    srcs = ["main.go"],
+    srcs = [
+        "main.go",
+        "rootfs.go",
+    ],
     importpath = "github.com/motiejus/code/undocker",
     visibility = ["//visibility:private"],
     deps = ["@com_github_jessevdk_go_flags//:go-flags"],
diff --git a/main.go b/main.go
index 36ade5a..1a6250c 100644
--- a/main.go
+++ b/main.go
@@ -1,19 +1,20 @@
 package main
 
 import (
-	"fmt"
 	"os"
-	"errors"
 
 	goflags "github.com/jessevdk/go-flags"
 )
 
-type opts struct {
-	PositionalArgs struct {
-		Infile     goflags.Filename `long:"infile" description:"Docker container tarball"`
-		Outfile string           `long:"outfile" description:"Output tarball"`
-	} `positional-args:"yes" required:"yes"`
-}
+type (
+	params struct {
+		RootFS   cmdRootFS   `command:"rootfs" description:"Unpack a docker container image to a single filesystem tarball"`
+		Manifest cmdManifest `command:"manifest"`
+	}
+
+	cmdManifest struct{} // stub
+
+)
 
 func main() {
 	if err := run(os.Args); err != nil {
@@ -23,17 +24,10 @@ func main() {
 }
 
 func run(args []string) error {
-	var flags opts
-	args1, err := goflags.ParseArgs(&flags, args)
-	if err != nil {
+	var opts params
+	if _, err := goflags.ParseArgs(&opts, args[1:]); err != nil {
 		return err
 	}
-	if len(args1) != 0 {
-		return errors.New("too many args")
-	}
-
-	fmt.Printf("infile: %s\n", flags.PositionalArgs.Infile)
-	fmt.Printf("outfile: %s\n", flags.PositionalArgs.Outfile)
 
 	return nil
 }
diff --git a/rootfs.go b/rootfs.go
new file mode 100644
index 0000000..03f1efd
--- /dev/null
+++ b/rootfs.go
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"errors"
+
+	goflags "github.com/jessevdk/go-flags"
+)
+
+type cmdRootFS struct {
+	PositionalArgs struct {
+		Infile  goflags.Filename `long:"infile" description:"Input tarball"`
+		Outfile string           `long:"outfile" description:"Output tarball (flattened file system)"`
+	} `positional-args:"yes" required:"yes"`
+}
+
+func (r *cmdRootFS) Execute(args []string) error {
+	if len(args) != 0 {
+		return errors.New("too many args")
+	}
+	return nil
+}