Alow not a DinD mode of operation

plugin.go

@@ -6,10 +6,17 @@ import (
 	"os"
 	"os/exec"
 	"strings"
+	"bufio"
+	"path"
+	"context"
+	"runtime"
 
 	"github.com/drone-plugins/drone-github-actions/daemon"
 	"github.com/drone-plugins/drone-github-actions/utils"
 	"github.com/pkg/errors"
+
+	"github.com/opencontainers/selinux/go-selinux"
+	docker "github.com/docker/docker/client"
 )
 
 const (
@@ -17,6 +24,9 @@ const (
 	secretFile       = "/tmp/action.secrets"
 	workflowFile     = "/tmp/workflow.yml"
 	eventPayloadFile = "/tmp/event.json"
+
+	stdDockerSocketPath = "/var/run/docker.sock"
+	hiddenDockerSocketPath = "/var/run/hidden_docker.sock"
 )
 
 var (
@@ -64,7 +74,6 @@ func (p Plugin) Exec() error {
 		secretFile,
 		"--env-file",
 		envFile,
-		"-b",
 		"--detect-event",
 	}
 
@@ -86,11 +95,35 @@ func (p Plugin) Exec() error {
 		cmdArgs = append(cmdArgs, "-v")
 	}
 
+	if p.Daemon.Disabled {
+		hostWorkDirPath, guestWorkDirPath, err := getWorkDirPath(p, context.Background())
+		if err != nil {
+			return errors.Wrap(err, "failed to locate working directory on the host. You may use DinD instead by disabling daemon_off.")
+		}
+
+		bindModifiers := ""
+		if runtime.GOOS == "darwin" {
+			bindModifiers = ":delegated"
+		}
+		if selinux.GetEnabled() {
+			bindModifiers = ":z"
+		}
+		cmdArgs = append(cmdArgs, "--container-options",  fmt.Sprintf("--volume=%s:%s%s", hostWorkDirPath, guestWorkDirPath, bindModifiers))
+
+	} else {
+		cmdArgs = append(cmdArgs, "-b")
+	}
+
+
 	cmd := exec.Command("act", cmdArgs...)
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	trace(cmd)
 
+	if p.Daemon.Disabled && !p.Daemon.NotHiddenSocket {
+		cmd.Env = append(os.Environ(), fmt.Sprintf("DOCKER_HOST=%s", "unix://" + hiddenDockerSocketPath))
+	}
+
 	err := cmd.Run()
 	if err != nil {
 		return err
@@ -103,3 +136,67 @@ func (p Plugin) Exec() error {
 func trace(cmd *exec.Cmd) {
 	fmt.Fprintf(os.Stdout, "+ %s\n", strings.Join(cmd.Args, " "))
 }
+
+func getWorkDirPath(p Plugin, ctx context.Context) (string, string, error) {
+	// Connect to the docker
+	// Note: We use a custom "hidden" socket path
+	dockerSockPath := ""
+  if p.Daemon.NotHiddenSocket {
+		dockerSockPath = stdDockerSocketPath
+	} else {
+		dockerSockPath = hiddenDockerSocketPath
+	}
+
+	docker, err := docker.NewClient("unix://" + dockerSockPath, "v1.13.1", nil, nil)
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to create docker client")
+	}
+	defer docker.Close()
+
+	// Determine our container identifier
+	cntrId, err := getContainerId()
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to get our container id")
+	}	
+
+	// Find the proper mount
+	cwd, err := os.Getwd()
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to locate the working directory in the container")
+	}
+
+	cntr, err := docker.ContainerInspect(ctx, cntrId)
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to inspect ourselves as a container")
+	}	
+	for _, i := range cntr.Mounts {
+		if i.Destination == cwd {
+			return i.Source, i.Destination, nil
+		}
+	}
+
+	return "", "", errors.New("mount point with working directory not found")
+}
+
+func getContainerId() (string, error) {
+	file, err := os.Open("/proc/self/cgroup")
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	if !scanner.Scan() {
+		return "", errors.New("cgroup is empty")
+	}
+
+	// The file name is the container identifier
+	// Example: 12:rdma:/docker/a33940bf95ec6c57b6d79a3edfa784a1364ce840fb92c9a7f3951b9f7b0ccccb/docker/330d9b057fdd54b224cd38daf370524f7e8c567ccf95f33a2388f02c0b854982
+	cgroup := scanner.Text()
+	result := path.Base(cgroup)
+	if result == "." {
+		return "", errors.New("cgroup is unexpected")
+	}
+
+	return result, nil
+}