Merge pull request #2098 from docker/revert-1879-signals

Revert "signals"

Author: Ulysses Souza

cli/cmd/context/context.go

@@ -48,7 +48,7 @@ func exportCommand() *cobra.Command {
 		Use:   "export",
 		Short: "Export a context to a tar or kubeconfig file",
 		Run: func(cmd *cobra.Command, args []string) {
-			mobycli.Exec()
+			mobycli.Exec(cmd.Root())
 		},
 	}
 	cmd.Flags().Bool("kubeconfig", false, "Export as a kubeconfig file")
@@ -60,7 +60,7 @@ func importCommand() *cobra.Command {
 		Use:   "import",
 		Short: "Import a context from a tar or zip file",
 		Run: func(cmd *cobra.Command, args []string) {
-			mobycli.Exec()
+			mobycli.Exec(cmd.Root())
 		},
 	}
 	return cmd

cli/cmd/context/create.go

@@ -69,7 +69,7 @@ $ docker context create my-context --description "some description" --docker "ho
 		Use:   "create CONTEXT",
 		Short: "Create new context",
 		RunE: func(cmd *cobra.Command, args []string) error {
-			mobycli.Exec()
+			mobycli.Exec(cmd.Root())
 			return nil
 		},
 		Long: longHelp,

cli/cmd/context/inspect.go

@@ -27,7 +27,7 @@ func inspectCommand() *cobra.Command {
 		Use:   "inspect",
 		Short: "Display detailed information on one or more contexts",
 		RunE: func(cmd *cobra.Command, args []string) error {
-			mobycli.Exec()
+			mobycli.Exec(cmd.Root())
 			return nil
 		},
 	}

cli/cmd/context/ls.go

@@ -53,7 +53,7 @@ func listCommand() *cobra.Command {
 		Aliases: []string{"ls"},
 		Args:    cobra.NoArgs,
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return runList(opts)
+			return runList(cmd, opts)
 		},
 	}
 	cmd.Flags().BoolVarP(&opts.quiet, "quiet", "q", false, "Only show context names")
@@ -62,14 +62,14 @@ func listCommand() *cobra.Command {
 	return cmd
 }
 
-func runList(opts lsOpts) error {
+func runList(cmd *cobra.Command, opts lsOpts) error {
 	err := opts.validate()
 	if err != nil {
 		return err
 	}
 	format := strings.ToLower(strings.ReplaceAll(opts.format, " ", ""))
 	if format != "" && format != formatter.JSON && format != formatter.PRETTY && format != formatter.TemplateLegacyJSON {
-		mobycli.Exec()
+		mobycli.Exec(cmd.Root())
 		return nil
 	}
 

cli/cmd/context/update.go

@@ -56,7 +56,7 @@ $ docker context update my-context --description "some description" --docker "ho
 		Short: "Update a context",
 		Args:  cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return runUpdate(args[0])
+			return runUpdate(cmd, args[0])
 		},
 		Long: longHelp,
 	}
@@ -71,7 +71,7 @@ $ docker context update my-context --description "some description" --docker "ho
 	return cmd
 }
 
-func runUpdate(name string) error {
+func runUpdate(cmd *cobra.Command, name string) error {
 	s := store.Instance()
 	dockerContext, err := s.Get(name)
 	if err == nil && dockerContext != nil {
@@ -80,6 +80,6 @@ func runUpdate(name string) error {
 		}
 	}
 
-	mobycli.Exec()
+	mobycli.Exec(cmd.Root())
 	return nil
 }

cli/cmd/login/login.go

@@ -49,7 +49,7 @@ func Command() *cobra.Command {
 }
 
 func runLogin(cmd *cobra.Command, args []string) error {
-	mobycli.Exec()
+	mobycli.Exec(cmd.Root())
 	return nil
 }
 

cli/cmd/logout/logout.go

@@ -37,6 +37,6 @@ func Command() *cobra.Command {
 }
 
 func runLogout(cmd *cobra.Command, args []string) error {
-	mobycli.Exec()
+	mobycli.Exec(cmd.Root())
 	return nil
 }

cli/cmd/version.go

@@ -80,7 +80,7 @@ func getOutFromMoby(cmd *cobra.Command, args ...string) (string, error) {
 	// we don't want to fail on error, there is an error if the engine is not available but it displays client version info
 	// Still, technically the [] byte versionResult could be nil, just let the original command display what it has to display
 	if versionResult == nil {
-		mobycli.Exec()
+		mobycli.Exec(cmd.Root())
 		return "", nil
 	}
 	return string(versionResult), err

cli/main.go

@@ -195,7 +195,7 @@ func main() {
 
 	// --version should immediately be forwarded to the original cli
 	if opts.Version {
-		mobycli.Exec()
+		mobycli.Exec(root)
 	}
 
 	if opts.Config == "" {
@@ -209,7 +209,7 @@ func main() {
 
 	s, err := store.New(configDir)
 	if err != nil {
-		mobycli.Exec()
+		mobycli.Exec(root)
 	}
 	store.WithContextStore(s)
 

cli/mobycli/exec.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"os/signal"
 	"path/filepath"
 	"regexp"
 
@@ -48,7 +49,7 @@ func ExecIfDefaultCtxType(ctx context.Context, root *cobra.Command) {
 	currentCtx, err := s.Get(currentContext)
 	// Only run original docker command if the current context is not ours.
 	if err != nil || mustDelegateToMoby(currentCtx.Type()) {
-		Exec()
+		Exec(root)
 	}
 }
 
@@ -62,8 +63,10 @@ func mustDelegateToMoby(ctxType string) bool {
 }
 
 // Exec delegates to com.docker.cli if on moby context
-func Exec() {
-	err := RunDocker(os.Args[1:]...)
+func Exec(root *cobra.Command) {
+	childExit := make(chan bool)
+	err := RunDocker(childExit, os.Args[1:]...)
+	childExit <- true
 	if err != nil {
 		if exiterr, ok := err.(*exec.ExitError); ok {
 			exitCode := exiterr.ExitCode()
@@ -88,7 +91,7 @@ func Exec() {
 }
 
 // RunDocker runs a docker command, and forward signals to the shellout command (stops listening to signals when an event is sent to childExit)
-func RunDocker(args ...string) error {
+func RunDocker(childExit chan bool, args ...string) error {
 	execBinary, err := resolvepath.LookPath(ComDockerCli)
 	if err != nil {
 		execBinary = findBinary(ComDockerCli)
@@ -102,6 +105,29 @@ func RunDocker(args ...string) error {
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
+
+	signals := make(chan os.Signal, 1)
+	signal.Notify(signals) // catch all signals
+	go func() {
+		for {
+			select {
+			case sig := <-signals:
+				if cmd.Process == nil {
+					continue // can happen if receiving signal before the process is actually started
+				}
+				// In go1.14+, the go runtime issues SIGURG as an interrupt to
+				// support preemptable system calls on Linux. Since we can't
+				// forward that along we'll check that here.
+				if isRuntimeSig(sig) {
+					continue
+				}
+				_ = cmd.Process.Signal(sig)
+			case <-childExit:
+				return
+			}
+		}
+	}()
+
 	return cmd.Run()
 }