forward all signals to the container

Signed-off-by: Krasi Georgiev <krasi.root@gmail.com>

cmd/ctr/utils.go

@@ -1,11 +1,17 @@
 package main
 
 import (
+	gocontext "context"
 	"fmt"
 	"io/ioutil"
 	"os"
+	"os/signal"
 	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
 
+	"github.com/Sirupsen/logrus"
 	contentapi "github.com/containerd/containerd/api/services/content"
 	"github.com/containerd/containerd/api/services/execution"
 	imagesapi "github.com/containerd/containerd/api/services/images"
@@ -79,3 +85,47 @@ func waitContainer(events execution.ContainerService_EventsClient, id string, pi
 		}
 	}
 }
+
+func forwardAllSignals(containers execution.ContainerServiceClient, id string) chan os.Signal {
+	sigc := make(chan os.Signal, 128)
+	signal.Notify(sigc)
+
+	go func() {
+		for s := range sigc {
+			logrus.Debug("Forwarding signal ", s)
+			killRequest := &execution.KillRequest{
+				ID:     id,
+				Signal: uint32(s.(syscall.Signal)),
+				All:    false,
+			}
+			_, err := containers.Kill(gocontext.Background(), killRequest)
+			if err != nil {
+				logrus.WithError(err).Error("grpc event from kill")
+			}
+		}
+	}()
+	return sigc
+}
+
+func parseSignal(rawSignal string) (syscall.Signal, error) {
+	s, err := strconv.Atoi(rawSignal)
+	if err == nil {
+		sig := syscall.Signal(s)
+		for _, msig := range signalMap {
+			if sig == msig {
+				return sig, nil
+			}
+		}
+		return -1, fmt.Errorf("unknown signal %q", rawSignal)
+	}
+	signal, ok := signalMap[strings.TrimPrefix(strings.ToUpper(rawSignal), "SIG")]
+	if !ok {
+		return -1, fmt.Errorf("unknown signal %q", rawSignal)
+	}
+	return signal, nil
+}
+
+func stopCatch(sigc chan os.Signal) {
+	signal.Stop(sigc)
+	close(sigc)
+}