From a333fb34ef643d84d04a28dd03b7fe48e7a47730 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@jakstys.lt>
Date: Mon, 24 May 2021 00:11:58 +0300
Subject: [PATCH] cmdlxcconfig

---
 BUILD                                 |  1 +
 internal/cmdlxcconfig/BUILD           | 13 ++++++++
 internal/cmdlxcconfig/cmdlxcconfig.go | 45 +++++++++++++++++++++++++++
 internal/cmdrootfs/cmdrootfs.go       | 12 +++----
 main.go                               |  7 ++---
 5 files changed, 68 insertions(+), 10 deletions(-)
 create mode 100644 internal/cmdlxcconfig/BUILD
 create mode 100644 internal/cmdlxcconfig/cmdlxcconfig.go

diff --git a/BUILD b/BUILD
index c9adc08..a5a2102 100644
--- a/BUILD
+++ b/BUILD
@@ -6,6 +6,7 @@ go_library(
     importpath = "github.com/motiejus/code/undocker",
     visibility = ["//visibility:private"],
     deps = [
+        "//src/undocker/internal/cmdlxcconfig:go_default_library",
         "//src/undocker/internal/cmdrootfs:go_default_library",
         "@com_github_jessevdk_go_flags//:go_default_library",
     ],
diff --git a/internal/cmdlxcconfig/BUILD b/internal/cmdlxcconfig/BUILD
new file mode 100644
index 0000000..c738ba3
--- /dev/null
+++ b/internal/cmdlxcconfig/BUILD
@@ -0,0 +1,13 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["cmdlxcconfig.go"],
+    importpath = "github.com/motiejus/code/undocker/internal/cmdlxcconfig",
+    visibility = ["//src/undocker:__subpackages__"],
+    deps = [
+        "//src/undocker/lxcconfig:go_default_library",
+        "@com_github_jessevdk_go_flags//:go_default_library",
+        "@org_uber_go_multierr//:go_default_library",
+    ],
+)
diff --git a/internal/cmdlxcconfig/cmdlxcconfig.go b/internal/cmdlxcconfig/cmdlxcconfig.go
new file mode 100644
index 0000000..9feb357
--- /dev/null
+++ b/internal/cmdlxcconfig/cmdlxcconfig.go
@@ -0,0 +1,45 @@
+package cmdlxcconfig
+
+import (
+	"errors"
+	"os"
+
+	goflags "github.com/jessevdk/go-flags"
+	"github.com/motiejus/code/undocker/lxcconfig"
+	"go.uber.org/multierr"
+)
+
+// Command is "lxcconfig" command
+type Command struct {
+	PositionalArgs struct {
+		Infile  goflags.Filename `long:"infile" description:"Input tarball"`
+		Outfile string           `long:"outfile" description:"Output path, stdout is '-'"`
+	} `positional-args:"yes" required:"yes"`
+}
+
+// Execute executes lxcconfig Command
+func (c *Command) Execute(args []string) (err error) {
+	if len(args) != 0 {
+		return errors.New("too many args")
+	}
+
+	rd, err := os.Open(string(c.PositionalArgs.Infile))
+	if err != nil {
+		return err
+	}
+	defer func() { err = multierr.Append(err, rd.Close()) }()
+
+	var out *os.File
+	outf := string(c.PositionalArgs.Outfile)
+	if outf == "-" {
+		out = os.Stdout
+	} else {
+		out, err = os.Create(outf)
+		if err != nil {
+			return err
+		}
+	}
+	defer func() { err = multierr.Append(err, out.Close()) }()
+
+	return lxcconfig.LXCConfig(rd, out)
+}
diff --git a/internal/cmdrootfs/cmdrootfs.go b/internal/cmdrootfs/cmdrootfs.go
index 1e2b8cf..b53add4 100644
--- a/internal/cmdrootfs/cmdrootfs.go
+++ b/internal/cmdrootfs/cmdrootfs.go
@@ -9,28 +9,28 @@ import (
 	"go.uber.org/multierr"
 )
 
-// CmdRootFS is "rootfs" command
-type CmdRootFS struct {
+// Command is "rootfs" command
+type Command struct {
 	PositionalArgs struct {
 		Infile  goflags.Filename `long:"infile" description:"Input tarball"`
 		Outfile string           `long:"outfile" description:"Output path, stdout is '-'"`
 	} `positional-args:"yes" required:"yes"`
 }
 
-// Execute executes CmdRootFS
-func (r *CmdRootFS) Execute(args []string) (err error) {
+// Execute executes rootfs Command
+func (c *Command) Execute(args []string) (err error) {
 	if len(args) != 0 {
 		return errors.New("too many args")
 	}
 
-	rd, err := os.Open(string(r.PositionalArgs.Infile))
+	rd, err := os.Open(string(c.PositionalArgs.Infile))
 	if err != nil {
 		return err
 	}
 	defer func() { err = multierr.Append(err, rd.Close()) }()
 
 	var out *os.File
-	outf := string(r.PositionalArgs.Outfile)
+	outf := string(c.PositionalArgs.Outfile)
 	if outf == "-" {
 		out = os.Stdout
 	} else {
diff --git a/main.go b/main.go
index 69c7a55..dd87ca3 100644
--- a/main.go
+++ b/main.go
@@ -4,16 +4,15 @@ import (
 	"os"
 
 	goflags "github.com/jessevdk/go-flags"
+	"github.com/motiejus/code/undocker/internal/cmdlxcconfig"
 	"github.com/motiejus/code/undocker/internal/cmdrootfs"
 )
 
 type (
 	params struct {
-		RootFS   cmdrootfs.CmdRootFS `command:"rootfs" description:"Unpack a docker container image to a single filesystem tarball"`
-		Manifest cmdManifest         `command:"manifest"`
+		RootFS    cmdrootfs.Command    `command:"rootfs" description:"Unpack a docker container image to a single filesystem tarball"`
+		LXCConfig cmdlxcconfig.Command `command:"lxcconfig" description:"Create an LXC-compatible container configuration"`
 	}
-
-	cmdManifest struct{} // stub
 )
 
 func main() {