From b60682c426eedecb6891f0888a3f6e60969928f6 Mon Sep 17 00:00:00 2001
From: frank yang <yyb196@gmail.com>
Date: Sun, 30 Jul 2017 20:47:21 +0800
Subject: [PATCH] Fixes #520 #527 only assign pty path to one process named
 runv-shim whose lifecyle is same as the terminal.

After did a lot of tests in my environment, I found that if multiple processes
have opened the same pty, docker-containerd-shim wonn't get the close event
of pty and will get stucked on waiting streem terminate forever.

Because runv and runv-containerd don't have a controlling tty, when they
opening the pty, it will become their controlling tty automatically.
that's why it complained about "operation not permitted" in case which mentioned
in bug #520. AFAIK a pty can only become controlling tty of one process.

Signed-off-by: frank yang <yyb196@gmail.com>
---
 create.go | 20 +++++++++++++-------
 exec.go   |  2 +-
 shim.go   | 36 ++++++++++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/create.go b/create.go
index d7224322..d9d69d7f 100644
--- a/create.go
+++ b/create.go
@@ -16,6 +16,7 @@ import (
 	"github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/urfave/cli"
 	netcontext "golang.org/x/net/context"
+	"golang.org/x/sys/unix"
 )
 
 var createCommand = cli.Command{
@@ -245,7 +246,7 @@ func createContainer(context *cli.Context, container, namespace string, config *
 		return err
 	}
 
-	return ociCreate(context, container, "init", func(stdin, stdout, stderr string) error {
+	return ociCreate(context, container, "init", namespace, func(stdin, stdout, stderr string) error {
 		r := &types.CreateContainerRequest{
 			Id:         container,
 			Runtime:    "runv-create",
@@ -269,7 +270,7 @@ func createContainer(context *cli.Context, container, namespace string, config *
 
 }
 
-func ociCreate(context *cli.Context, container, process string, createFunc func(stdin, stdout, stderr string) error) error {
+func ociCreate(context *cli.Context, container, process, namespace string, createFunc func(stdin, stdout, stderr string) error) error {
 	path, err := osext.Executable()
 	if err != nil {
 		return fmt.Errorf("cannot find self executable path for %s: %v\n", os.Args[0], err)
@@ -298,10 +299,15 @@ func ociCreate(context *cli.Context, container, process string, createFunc func(
 		stdout = fmt.Sprintf("/proc/%d/fd/1", pid)
 		stderr = fmt.Sprintf("/proc/%d/fd/2", pid)
 	} else {
-		defer tty.Close()
-		stdin = tty.Name()
-		stdout = tty.Name()
-		stderr = tty.Name()
+		streamDir := filepath.Join(namespace, container)
+		if _, ex := os.Stat(streamDir); ex != nil && os.IsNotExist(ex) {
+			os.MkdirAll(streamDir, 0755)
+		}
+
+		stdin = fmt.Sprintf("%s/%s-0", streamDir, process)
+		unix.Mkfifo(stdin, 0)
+		stdout = fmt.Sprintf("%s/%s-1", streamDir, process)
+		unix.Mkfifo(stdout, 0)
 	}
 	err = createFunc(stdin, stdout, stderr)
 	if err != nil {
@@ -324,7 +330,7 @@ func ociCreate(context *cli.Context, container, process string, createFunc func(
 			args = append(args, "--proxy-exit-code", "--proxy-signal")
 		}
 		if tty != nil {
-			args = append(args, "--proxy-winsize")
+			args = append(args, "--proxy-winsize", "--input-pipe", stdin, "--output-pipe", stdout)
 		}
 		cmd = &exec.Cmd{
 			Path:   path,
diff --git a/exec.go b/exec.go
index a4f3ab48..831766f5 100644
--- a/exec.go
+++ b/exec.go
@@ -208,7 +208,7 @@ func runProcess(context *cli.Context, container string, config *specs.Process) (
 		monitorTtySize(c, container, process)
 	}
 
-	err = ociCreate(context, container, process, func(stdin, stdout, stderr string) error {
+	err = ociCreate(context, container, process, filepath.Join(context.GlobalString("root"), container, "namespace"), func(stdin, stdout, stderr string) error {
 		p := &types.AddProcessRequest{
 			Id:       container,
 			Pid:      process,
diff --git a/shim.go b/shim.go
index 6f7ce13d..4d930a5e 100644
--- a/shim.go
+++ b/shim.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -33,11 +34,46 @@ var shimCommand = cli.Command{
 		cli.BoolFlag{
 			Name: "proxy-winsize",
 		},
+		cli.StringFlag{
+			Name: "input-pipe",
+		},
+		cli.StringFlag{
+			Name: "output-pipe",
+		},
 	},
 	Action: func(context *cli.Context) error {
 		root := context.GlobalString("root")
 		container := context.String("container")
 		process := context.String("process")
+
+		var stdinStream, stdoutStream io.ReadWriteCloser
+		var err error
+		stdinPath := context.String("input-pipe")
+		stdoutPath := context.String("output-pipe")
+		if context.Bool("proxy-winsize") {
+			stdinStream, err = os.OpenFile(stdinPath, syscall.O_WRONLY, 0)
+			if err != nil {
+				return err
+			}
+
+			stdoutStream, err = os.OpenFile(stdoutPath, syscall.O_RDONLY, 0)
+			if err != nil {
+				return err
+			}
+		}
+
+		if stdinStream != nil {
+			go func() {
+				io.Copy(stdinStream, os.Stdin)
+			}()
+		}
+
+		if stdoutStream != nil {
+			go func() {
+				io.Copy(os.Stdout, stdoutStream)
+			}()
+		}
+
 		c, err := getClient(filepath.Join(root, container, "namespace", "namespaced.sock"))
 		if err != nil {
 			return cli.NewExitError(fmt.Sprintf("failed to get client: %v", err), -1)