3 files changed, 246 insertions, 0 deletions
diff --git a/pkg/varlinkapi/attach.go b/pkg/varlinkapi/attach.go
new file mode 100644
index 000000000..53c4d1ff6
--- /dev/null
+++ b/pkg/varlinkapi/attach.go
@@ -0,0 +1,75 @@
+// +build varlink
+
+package varlinkapi
+
+import (
+	"io"
+
+	"github.com/containers/libpod/cmd/podman/varlink"
+	"github.com/containers/libpod/libpod"
+	"github.com/containers/libpod/pkg/varlinkapi/virtwriter"
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+// Close is method to close the writer
+
+// Attach ...
+func (i *LibpodAPI) Attach(call iopodman.VarlinkCall, name string) error {
+	var finalErr error
+	resize := make(chan remotecommand.TerminalSize)
+	errChan := make(chan error)
+
+	if !call.WantsUpgrade() {
+		return call.ReplyErrorOccurred("client must use upgraded connection to attach")
+	}
+	ctr, err := i.Runtime.LookupContainer(name)
+	if err != nil {
+		return call.ReplyErrorOccurred(err.Error())
+	}
+
+	// These are the varlink sockets
+	reader := call.Call.Reader
+	writer := call.Call.Writer
+
+	// This pipe is used to pass stdin from the client to the input stream
+	// once the msg has been "decoded"
+	pr, pw := io.Pipe()
+
+	stdoutWriter := virtwriter.NewVirtWriteCloser(writer, virtwriter.ToStdout)
+	// TODO if runc ever starts passing stderr, we can too
+	//stderrWriter := NewVirtWriteCloser(writer, ToStderr)
+
+	streams := libpod.AttachStreams{
+		OutputStream: stdoutWriter,
+		InputStream:  pr,
+		// Runc eats the error stream
+		ErrorStream:  stdoutWriter,
+		AttachInput:  true,
+		AttachOutput: true,
+		// Runc eats the error stream
+		AttachError: true,
+	}
+
+	go func() {
+		if err := virtwriter.Reader(reader, nil, nil, pw, resize); err != nil {
+			errChan <- err
+		}
+	}()
+
+	go func() {
+		// TODO allow for customizable detach keys
+		if err := ctr.Attach(&streams, "", resize); err != nil {
+			errChan <- err
+		}
+	}()
+
+	select {
+	// Blocking on an error
+	case finalErr = <-errChan:
+		// Need to close up shop
+		_ = finalErr
+	}
+	quitWriter := virtwriter.NewVirtWriteCloser(writer, virtwriter.Quit)
+	_, err = quitWriter.Write([]byte("HANG-UP"))
+	return call.Writer.Flush()
+}
diff --git a/pkg/varlinkapi/containers.go b/pkg/varlinkapi/containers.go
index 816a72953..17792ccfe 100644
--- a/pkg/varlinkapi/containers.go
+++ b/pkg/varlinkapi/containers.go
@@ -634,6 +634,22 @@ func (i *LibpodAPI) GetContainerStatsWithHistory(call iopodman.VarlinkCall, prev
 	return call.ReplyGetContainerStatsWithHistory(cStats)
 }
 
+// Spec ...
+func (i *LibpodAPI) Spec(call iopodman.VarlinkCall, name string) error {
+	ctr, err := i.Runtime.LookupContainer(name)
+	if err != nil {
+		return call.ReplyErrorOccurred(err.Error())
+	}
+
+	spec := ctr.Spec()
+	b, err := json.Marshal(spec)
+	if err != nil {
+		return call.ReplyErrorOccurred(err.Error())
+	}
+
+	return call.ReplySpec(string(b))
+}
+
 // GetContainersLogs is the varlink endpoint to obtain one or more container logs
 func (i *LibpodAPI) GetContainersLogs(call iopodman.VarlinkCall, names []string, follow, latest bool, since string, tail int64, timestamps bool) error {
 	var wg sync.WaitGroup
diff --git a/pkg/varlinkapi/virtwriter/virtwriter.go b/pkg/varlinkapi/virtwriter/virtwriter.go
new file mode 100644
index 000000000..3adaf6e17
--- /dev/null
+++ b/pkg/varlinkapi/virtwriter/virtwriter.go
@@ -0,0 +1,155 @@
+package virtwriter
+
+import (
+	"bufio"
+	"encoding/binary"
+	"encoding/json"
+	"errors"
+	"io"
+	"os"
+
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+// SocketDest is the "key" to where IO should go on the varlink
+// multiplexed socket
+type SocketDest int
+
+const (
+	// ToStdout indicates traffic should go stdout
+	ToStdout SocketDest = iota
+	// ToStdin indicates traffic came from stdin
+	ToStdin SocketDest = iota
+	// ToStderr indicates traffuc should go to stderr
+	ToStderr SocketDest = iota
+	// TerminalResize indicates a terminal resize event has occurred
+	// and data should be passed to resizer
+	TerminalResize SocketDest = iota
+	// Quit and detach
+	Quit SocketDest = iota
+)
+
+// IntToSocketDest returns a socketdest based on integer input
+func IntToSocketDest(i int) SocketDest {
+	switch i {
+	case ToStdout.Int():
+		return ToStdout
+	case ToStderr.Int():
+		return ToStderr
+	case ToStdin.Int():
+		return ToStdin
+	case TerminalResize.Int():
+		return TerminalResize
+	case Quit.Int():
+		return Quit
+	default:
+		return ToStderr
+	}
+}
+
+// Int returns the integer representation of the socket dest
+func (sd SocketDest) Int() int {
+	return int(sd)
+}
+
+// VirtWriteCloser are writers for attach which include the dest
+// of the data
+type VirtWriteCloser struct {
+	writer *bufio.Writer
+	dest   SocketDest
+}
+
+// NewVirtWriteCloser is a constructor
+func NewVirtWriteCloser(w *bufio.Writer, dest SocketDest) VirtWriteCloser {
+	return VirtWriteCloser{w, dest}
+}
+
+// Close is a required method for a writecloser
+func (v VirtWriteCloser) Close() error {
+	return nil
+}
+
+// Write prepends a header to the input message.  The header is
+// 8bytes.  Position one contains the destination.  Positions
+// 5,6,7,8 are a big-endian encoded uint32 for len of the message.
+func (v VirtWriteCloser) Write(input []byte) (int, error) {
+	header := []byte{byte(v.dest), 0, 0, 0}
+	// Go makes us define the byte for big endian
+	mlen := make([]byte, 4)
+	binary.BigEndian.PutUint32(mlen, uint32(len(input)))
+	// append the message len to the header
+	msg := append(header, mlen...)
+	// append the message to the header
+	msg = append(msg, input...)
+	_, err := v.writer.Write(msg)
+	if err != nil {
+		return 0, err
+	}
+	err = v.writer.Flush()
+	return len(input), err
+}
+
+// Reader decodes the content that comes over the wire and directs it to the proper destination.
+func Reader(r *bufio.Reader, output, errput *os.File, input *io.PipeWriter, resize chan remotecommand.TerminalSize) error {
+	var saveb []byte
+	var eom int
+	for {
+		readb := make([]byte, 32*1024)
+		n, err := r.Read(readb)
+		// TODO, later may be worth checking in len of the read is 0
+		if err != nil {
+			return err
+		}
+		b := append(saveb, readb[0:n]...)
+		// no sense in reading less than the header len
+		for len(b) > 7 {
+			eom = int(binary.BigEndian.Uint32(b[4:8])) + 8
+			// The message and header are togther
+			if len(b) >= eom {
+				out := append([]byte{}, b[8:eom]...)
+
+				switch IntToSocketDest(int(b[0])) {
+				case ToStdout:
+					n, err := output.Write(out)
+					if err != nil {
+						return err
+					}
+					if n < len(out) {
+						return errors.New("short write error occurred on stdout")
+					}
+				case ToStderr:
+					n, err := errput.Write(out)
+					if err != nil {
+						return err
+					}
+					if n < len(out) {
+						return errors.New("short write error occurred on stderr")
+					}
+				case ToStdin:
+					n, err := input.Write(out)
+					if err != nil {
+						return err
+					}
+					if n < len(out) {
+						return errors.New("short write error occurred on stdin")
+					}
+				case TerminalResize:
+					// Resize events come over in bytes, need to be reserialized
+					resizeEvent := remotecommand.TerminalSize{}
+					if err := json.Unmarshal(out, &resizeEvent); err != nil {
+						return err
+					}
+					resize <- resizeEvent
+				case Quit:
+					return nil
+				}
+				b = b[eom:]
+			} else {
+				//	We do not have the header and full message, need to slurp again
+				saveb = b
+				break
+			}
+		}
+	}
+	return nil
+}