chore: more wip - making progress

cmd/cmd.go

@@ -1,9 +1,16 @@
 package cmd
 
 import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
 	"os"
+	"path/filepath"
 
 	"github.com/nixpig/brownie/internal/commands"
+	"github.com/nixpig/brownie/pkg"
+	"github.com/rs/zerolog"
 	"github.com/spf13/cobra"
 )
 
@@ -12,10 +19,11 @@ var Root = &cobra.Command{
 	Short:   "An experimental Linux container runtime.",
 	Long:    "An experimental Linux container runtime; working towards OCI Runtime Spec compliance.",
 	Example: "",
+	Version: "0.0.1",
 }
 
-func createCmd() *cobra.Command {
-	var create = &cobra.Command{
+func createCmd(log *zerolog.Logger) *cobra.Command {
+	create := &cobra.Command{
 		Use:     "create [flags] CONTAINER_ID",
 		Short:   "Create a container",
 		Args:    cobra.ExactArgs(1),
@@ -45,7 +53,7 @@ func createCmd() *cobra.Command {
 				PIDFile:       pidFile,
 			}
 
-			return commands.Create(opts)
+			return commands.Create(opts, log)
 		},
 	}
 
@@ -57,16 +65,24 @@ func createCmd() *cobra.Command {
 	return create
 }
 
-var Start = &cobra.Command{
-	Use:     "start [flags] CONTAINER_ID",
-	Short:   "Start a container",
-	Args:    cobra.ExactArgs(1),
-	Example: "  brownie start busybox",
-	RunE: func(cmd *cobra.Command, args []string) error {
-		containerID := args[0]
+func startCmd(log *zerolog.Logger) *cobra.Command {
+	start := &cobra.Command{
+		Use:     "start [flags] CONTAINER_ID",
+		Short:   "Start a container",
+		Args:    cobra.ExactArgs(1),
+		Example: "  brownie start busybox",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			containerID := args[0]
 
-		return commands.Start(containerID)
-	},
+			opts := &commands.StartOpts{
+				ID: containerID,
+			}
+
+			return commands.Start(opts, log)
+		},
+	}
+
+	return start
 }
 
 var Kill = &cobra.Command{
@@ -94,41 +110,88 @@ var Delete = &cobra.Command{
 	},
 }
 
-var Fork = &cobra.Command{
-	Use:     "fork [flags] CONTAINER_ID INIT_SOCK_ADDR CONTAINER_SOCK_ADDR",
-	Short:   "Fork container process\n\n \033[31m ⚠ FOR INTERNAL USE ONLY - DO NOT RUN DIRECTLY ⚠ \033[0m",
-	Args:    cobra.ExactArgs(3),
-	Example: "\n -- FOR INTERNAL USE ONLY --",
-	Hidden:  true,
-	Run: func(cmd *cobra.Command, args []string) {
-		containerID := args[0]
-		initSockAddr := args[1]
-		containerSockAddr := args[2]
+func forkCmd(log *zerolog.Logger) *cobra.Command {
+	fork := &cobra.Command{
+		Use:     "fork [flags] CONTAINER_ID INIT_SOCK_ADDR CONTAINER_SOCK_ADDR",
+		Short:   "Fork container process\n\n \033[31m ⚠ FOR INTERNAL USE ONLY - DO NOT RUN DIRECTLY ⚠ \033[0m",
+		Args:    cobra.ExactArgs(4),
+		Example: "\n -- FOR INTERNAL USE ONLY --",
+		Hidden:  true,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			stage := args[0]
+			containerID := args[1]
+			initSockAddr := args[2]
+			containerSockAddr := args[3]
 
-		commands.Fork(containerID, initSockAddr, containerSockAddr)
-	},
+			if commands.ForkStage(stage) != commands.ForkIntermediate && commands.ForkStage(stage) != commands.ForkDetached {
+				return errors.New("invalidate fork stage")
+			}
+
+			opts := &commands.ForkOpts{
+				ID:                containerID,
+				InitSockAddr:      initSockAddr,
+				ContainerSockAddr: containerSockAddr,
+				Stage:             commands.ForkStage(stage),
+			}
+
+			return commands.Fork(opts, log)
+		},
+	}
+
+	return fork
 }
 
-var QueryState = &cobra.Command{
-	Use:     "state [flags] CONTAINER_ID",
-	Short:   "Query a container state",
-	Args:    cobra.ExactArgs(1),
-	Example: "  brownie state busybox",
-	RunE: func(cmd *cobra.Command, args []string) error {
-		containerID := args[0]
+func stateCmd(log *zerolog.Logger) *cobra.Command {
+	state := &cobra.Command{
+		Use:     "state [flags] CONTAINER_ID",
+		Short:   "Query a container state",
+		Args:    cobra.ExactArgs(1),
+		Example: "  brownie state busybox",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			containerID := args[0]
 
-		return commands.QueryState(containerID)
-	},
+			opts := &commands.StateOpts{
+				ID: containerID,
+			}
+
+			state, err := commands.State(opts, log)
+			if err != nil {
+				e := cmd.ErrOrStderr()
+				e.Write([]byte(err.Error()))
+				return err
+			}
+
+			var prettified bytes.Buffer
+			json.Indent(&prettified, []byte(state), "", "  ")
+
+			fmt.Fprint(cmd.OutOrStdout(), prettified.String())
+			return nil
+		},
+	}
+
+	return state
 }
 
 func init() {
+	logfile, err := os.OpenFile(
+		filepath.Join(pkg.BrownieRootDir, "logs", "brownie.log"),
+		os.O_APPEND|os.O_CREATE|os.O_WRONLY,
+		0644,
+	)
+	if err != nil {
+		fmt.Println("open log file: %w", err)
+		os.Exit(1)
+	}
+
+	log := zerolog.New(logfile).With().Timestamp().Logger()
+
 	Root.AddCommand(
-		createCmd(),
-		Start,
-		QueryState,
+		createCmd(&log),
+		startCmd(&log),
+		stateCmd(&log),
 		Delete,
 		Kill,
-		Fork,
+		forkCmd(&log),
 	)
 
 	Root.CompletionOptions.HiddenDefaultCmd = true

go.mod

@@ -10,7 +10,10 @@ require (
 
 require (
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/rs/zerolog v1.33.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	golang.org/x/sync v0.3.0 // indirect
-	golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8 // indirect
+	golang.org/x/sys v0.12.0 // indirect
 )

go.sum

@@ -1,12 +1,23 @@
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
+github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/opencontainers/runtime-spec v1.2.0 h1:z97+pHb3uELt/yiAWD691HNHQIF07bE7dzrbT927iTk=
 github.com/opencontainers/runtime-spec v1.2.0/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/C5hL+LL3ko9hs6T5lQ0=
 github.com/otiai10/copy v1.14.0 h1:dCI/t1iTdYGtkvCuBG2BgR6KZa83PTclw4U5n2wAllU=
 github.com/otiai10/copy v1.14.0/go.mod h1:ECfuL02W+/FkTWZWgQqXPWZgW9oeKCSQ5qVfSc4qc4w=
 github.com/otiai10/mint v1.5.1 h1:XaPLeE+9vGbuyEHem1JNk3bYc7KKqyI/na0/mLd/Kks=
 github.com/otiai10/mint v1.5.1/go.mod h1:MJm72SBthJjz8qhefc4z1PYEieWmy8Bku7CjcAqyUSM=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
+github.com/rs/zerolog v1.33.0 h1:1cU2KZkvPxNyfgEmhHAz/1A9Bz+llsdYzklWFzgp0r8=
+github.com/rs/zerolog v1.33.0/go.mod h1:/7mN4D5sKwJLZQ2b/znpjC3/GQWY/xaDXUM0kKWRHss=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/spf13/cobra v1.8.1 h1:e5/vxKd/rZsfSJMUX1agtjeTDf+qv1/JdBF8gg5k9ZM=
 github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
@@ -16,5 +27,9 @@ golang.org/x/sync v0.3.0 h1:ftCYgMx6zT/asHUrPw8BLLscYtGznsLAnjq5RH9P66E=
 golang.org/x/sync v0.3.0/go.mod h1:FU7BRWz2tNW+3quACPkgCx/L+uEAv1htQ0V83Z9Rj+Y=
 golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8 h1:0A+M6Uqn+Eje4kHMK80dtF3JCXC4ykBgQG4Fe06QRhQ=
 golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
+golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

internal/commands/create.go

@@ -2,18 +2,17 @@ package commands
 
 import (
 	"encoding/json"
-	"errors"
 	"fmt"
 	"net"
 	"os"
 	"os/exec"
 	"path/filepath"
-	"syscall"
 
 	"github.com/nixpig/brownie/internal"
 	"github.com/nixpig/brownie/pkg"
 	"github.com/opencontainers/runtime-spec/specs-go"
 	cp "github.com/otiai10/copy"
+	"github.com/rs/zerolog"
 )
 
 type CreateOpts struct {
@@ -23,7 +22,7 @@ type CreateOpts struct {
 	PIDFile       string
 }
 
-func Create(opts *CreateOpts) error {
+func Create(opts *CreateOpts, log *zerolog.Logger) error {
 	containerPath := filepath.Join(pkg.BrownieRootDir, "containers", opts.ID)
 
 	if stat, _ := os.Stat(containerPath); stat != nil {
@@ -92,55 +91,23 @@ func Create(opts *CreateOpts) error {
 		"/proc/self/exe",
 		[]string{
 			"fork",
+			string(ForkIntermediate),
 			opts.ID,
 			initSockAddr,
 			containerSockAddr,
 		}...)
 
-	if spec.Linux == nil {
-		return errors.New("not a linux container")
-	}
-	var cloneFlags uintptr
-	for _, ns := range spec.Linux.Namespaces {
-		ns := internal.LinuxNamespace(ns)
-		flag, err := ns.ToFlag()
-		if err != nil {
-			return err
-		}
-
-		cloneFlags = cloneFlags | flag
-	}
-
-	// apply configuration, e.g. devices, proc, etc...
-	forkCmd.SysProcAttr = &syscall.SysProcAttr{
-		Cloneflags:   cloneFlags,
-		Unshareflags: syscall.CLONE_NEWNS,
-		UidMappings: []syscall.SysProcIDMap{
-			{
-				ContainerID: 0,
-				HostID:      int(spec.Process.User.UID),
-				Size:        1,
-			},
-		},
-		GidMappings: []syscall.SysProcIDMap{
-			{
-				ContainerID: 0,
-				HostID:      int(spec.Process.User.GID),
-				Size:        1,
-			},
-		},
-	}
-
-	forkCmd.Start()
-	pid := forkCmd.Process.Pid
-	if err := forkCmd.Process.Release(); err != nil {
-		return fmt.Errorf("detach from process: %w", err)
+	forkCmd.Stdout = os.Stdout
+	forkCmd.Stderr = os.Stderr
+	if err := forkCmd.Run(); err != nil {
+		return fmt.Errorf("fork: %w", err)
 	}
 
 	// wait for container to be ready
 	if err := os.RemoveAll(initSockAddr); err != nil {
 		return err
 	}
+
 	listener, err := net.Listen("unix", initSockAddr)
 	if err != nil {
 		return fmt.Errorf("failed to listen on init socket: %w", err)
@@ -161,12 +128,18 @@ func Create(opts *CreateOpts) error {
 			continue
 		}
 
-		if string(b[:n]) == "ready" {
+		if len(b) > 0 {
+			log.Info().Str("msg", string(b)).Msg("received")
+		}
+
+		if len(b) >= 5 && string(b[:5]) == "ready" {
+			log.Info().Msg("received 'ready' message")
 			break
 		}
 	}
 
 	state.Status = specs.StateCreated
+	pid := forkCmd.Process.Pid
 	state.Pid = pid
 	if err := internal.SaveState(state); err != nil {
 		return fmt.Errorf("save created state: %w", err)