1 files changed, 513 insertions, 0 deletions
diff --git a/pkg/go-runsc/runsc.go b/pkg/go-runsc/runsc.go
new file mode 100644
index 000000000..364ff54bc
--- /dev/null
+++ b/pkg/go-runsc/runsc.go
@@ -0,0 +1,513 @@
+/*
+Copyright The containerd Authors.
+Copyright 2018 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package runsc
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"syscall"
+	"time"
+
+	runc "github.com/containerd/go-runc"
+	specs "github.com/opencontainers/runtime-spec/specs-go"
+)
+
+var Monitor runc.ProcessMonitor = runc.Monitor
+
+// DefaultCommand is the default command for Runsc
+const DefaultCommand = "runsc"
+
+// Runsc is the client to the runsc cli
+type Runsc struct {
+	Command      string
+	PdeathSignal syscall.Signal
+	Setpgid      bool
+	Root         string
+	Log          string
+	LogFormat    runc.Format
+	Config       map[string]string
+}
+
+// List returns all containers created inside the provided runsc root directory
+func (r *Runsc) List(context context.Context) ([]*runc.Container, error) {
+	data, err := cmdOutput(r.command(context, "list", "--format=json"), false)
+	if err != nil {
+		return nil, err
+	}
+	var out []*runc.Container
+	if err := json.Unmarshal(data, &out); err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// State returns the state for the container provided by id
+func (r *Runsc) State(context context.Context, id string) (*runc.Container, error) {
+	data, err := cmdOutput(r.command(context, "state", id), true)
+	if err != nil {
+		return nil, fmt.Errorf("%s: %s", err, data)
+	}
+	var c runc.Container
+	if err := json.Unmarshal(data, &c); err != nil {
+		return nil, err
+	}
+	return &c, nil
+}
+
+type CreateOpts struct {
+	runc.IO
+	// PidFile is a path to where a pid file should be created
+	PidFile       string
+	ConsoleSocket runc.ConsoleSocket
+	// UserLog is a path to where runsc user log should be generated.
+	UserLog string
+}
+
+func (o *CreateOpts) args() (out []string, err error) {
+	if o.PidFile != "" {
+		abs, err := filepath.Abs(o.PidFile)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, "--pid-file", abs)
+	}
+	if o.ConsoleSocket != nil {
+		out = append(out, "--console-socket", o.ConsoleSocket.Path())
+	}
+	if o.UserLog != "" {
+		out = append(out, "--user-log", o.UserLog)
+	}
+	return out, nil
+}
+
+// Create creates a new container and returns its pid if it was created successfully
+func (r *Runsc) Create(context context.Context, id, bundle string, opts *CreateOpts) error {
+	args := []string{"create", "--bundle", bundle}
+	if opts != nil {
+		oargs, err := opts.args()
+		if err != nil {
+			return err
+		}
+		args = append(args, oargs...)
+	}
+	cmd := r.command(context, append(args, id)...)
+	if opts != nil && opts.IO != nil {
+		opts.Set(cmd)
+	}
+
+	if cmd.Stdout == nil && cmd.Stderr == nil {
+		data, err := cmdOutput(cmd, true)
+		if err != nil {
+			return fmt.Errorf("%s: %s", err, data)
+		}
+		return nil
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return err
+	}
+	if opts != nil && opts.IO != nil {
+		if c, ok := opts.IO.(runc.StartCloser); ok {
+			if err := c.CloseAfterStart(); err != nil {
+				return err
+			}
+		}
+	}
+	status, err := Monitor.Wait(cmd, ec)
+	if err == nil && status != 0 {
+		err = fmt.Errorf("%s did not terminate sucessfully", cmd.Args[0])
+	}
+
+	return err
+}
+
+// Start will start an already created container
+func (r *Runsc) Start(context context.Context, id string, cio runc.IO) error {
+	cmd := r.command(context, "start", id)
+	if cio != nil {
+		cio.Set(cmd)
+	}
+
+	if cmd.Stdout == nil && cmd.Stderr == nil {
+		data, err := cmdOutput(cmd, true)
+		if err != nil {
+			return fmt.Errorf("%s: %s", err, data)
+		}
+		return nil
+	}
+
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return err
+	}
+	if cio != nil {
+		if c, ok := cio.(runc.StartCloser); ok {
+			if err := c.CloseAfterStart(); err != nil {
+				return err
+			}
+		}
+	}
+	status, err := Monitor.Wait(cmd, ec)
+	if err == nil && status != 0 {
+		err = fmt.Errorf("%s did not terminate sucessfully", cmd.Args[0])
+	}
+
+	return err
+}
+
+type waitResult struct {
+	ID         string `json:"id"`
+	ExitStatus int    `json:"exitStatus"`
+}
+
+// Wait will wait for a running container, and return its exit status.
+// TODO(random-liu): Add exec process support.
+func (r *Runsc) Wait(context context.Context, id string) (int, error) {
+	data, err := cmdOutput(r.command(context, "wait", id), true)
+	if err != nil {
+		return 0, fmt.Errorf("%s: %s", err, data)
+	}
+	var res waitResult
+	if err := json.Unmarshal(data, &res); err != nil {
+		return 0, err
+	}
+	return res.ExitStatus, nil
+}
+
+type ExecOpts struct {
+	runc.IO
+	PidFile         string
+	InternalPidFile string
+	ConsoleSocket   runc.ConsoleSocket
+	Detach          bool
+}
+
+func (o *ExecOpts) args() (out []string, err error) {
+	if o.ConsoleSocket != nil {
+		out = append(out, "--console-socket", o.ConsoleSocket.Path())
+	}
+	if o.Detach {
+		out = append(out, "--detach")
+	}
+	if o.PidFile != "" {
+		abs, err := filepath.Abs(o.PidFile)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, "--pid-file", abs)
+	}
+	if o.InternalPidFile != "" {
+		abs, err := filepath.Abs(o.InternalPidFile)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, "--internal-pid-file", abs)
+	}
+	return out, nil
+}
+
+// Exec executres and additional process inside the container based on a full
+// OCI Process specification
+func (r *Runsc) Exec(context context.Context, id string, spec specs.Process, opts *ExecOpts) error {
+	f, err := ioutil.TempFile(os.Getenv("XDG_RUNTIME_DIR"), "runsc-process")
+	if err != nil {
+		return err
+	}
+	defer os.Remove(f.Name())
+	err = json.NewEncoder(f).Encode(spec)
+	f.Close()
+	if err != nil {
+		return err
+	}
+	args := []string{"exec", "--process", f.Name()}
+	if opts != nil {
+		oargs, err := opts.args()
+		if err != nil {
+			return err
+		}
+		args = append(args, oargs...)
+	}
+	cmd := r.command(context, append(args, id)...)
+	if opts != nil && opts.IO != nil {
+		opts.Set(cmd)
+	}
+	if cmd.Stdout == nil && cmd.Stderr == nil {
+		data, err := cmdOutput(cmd, true)
+		if err != nil {
+			return fmt.Errorf("%s: %s", err, data)
+		}
+		return nil
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return err
+	}
+	if opts != nil && opts.IO != nil {
+		if c, ok := opts.IO.(runc.StartCloser); ok {
+			if err := c.CloseAfterStart(); err != nil {
+				return err
+			}
+		}
+	}
+	status, err := Monitor.Wait(cmd, ec)
+	if err == nil && status != 0 {
+		err = fmt.Errorf("%s did not terminate sucessfully", cmd.Args[0])
+	}
+	return err
+}
+
+// Run runs the create, start, delete lifecycle of the container
+// and returns its exit status after it has exited
+func (r *Runsc) Run(context context.Context, id, bundle string, opts *CreateOpts) (int, error) {
+	args := []string{"run", "--bundle", bundle}
+	if opts != nil {
+		oargs, err := opts.args()
+		if err != nil {
+			return -1, err
+		}
+		args = append(args, oargs...)
+	}
+	cmd := r.command(context, append(args, id)...)
+	if opts != nil && opts.IO != nil {
+		opts.Set(cmd)
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return -1, err
+	}
+	return Monitor.Wait(cmd, ec)
+}
+
+type DeleteOpts struct {
+	Force bool
+}
+
+func (o *DeleteOpts) args() (out []string) {
+	if o.Force {
+		out = append(out, "--force")
+	}
+	return out
+}
+
+// Delete deletes the container
+func (r *Runsc) Delete(context context.Context, id string, opts *DeleteOpts) error {
+	args := []string{"delete"}
+	if opts != nil {
+		args = append(args, opts.args()...)
+	}
+	return r.runOrError(r.command(context, append(args, id)...))
+}
+
+// KillOpts specifies options for killing a container and its processes
+type KillOpts struct {
+	All bool
+	Pid int
+}
+
+func (o *KillOpts) args() (out []string) {
+	if o.All {
+		out = append(out, "--all")
+	}
+	if o.Pid != 0 {
+		out = append(out, "--pid", strconv.Itoa(o.Pid))
+	}
+	return out
+}
+
+// Kill sends the specified signal to the container
+func (r *Runsc) Kill(context context.Context, id string, sig int, opts *KillOpts) error {
+	args := []string{
+		"kill",
+	}
+	if opts != nil {
+		args = append(args, opts.args()...)
+	}
+	return r.runOrError(r.command(context, append(args, id, strconv.Itoa(sig))...))
+}
+
+// Stats return the stats for a container like cpu, memory, and io
+func (r *Runsc) Stats(context context.Context, id string) (*runc.Stats, error) {
+	cmd := r.command(context, "events", "--stats", id)
+	rd, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		rd.Close()
+		Monitor.Wait(cmd, ec)
+	}()
+	var e runc.Event
+	if err := json.NewDecoder(rd).Decode(&e); err != nil {
+		return nil, err
+	}
+	return e.Stats, nil
+}
+
+// Events returns an event stream from runsc for a container with stats and OOM notifications
+func (r *Runsc) Events(context context.Context, id string, interval time.Duration) (chan *runc.Event, error) {
+	cmd := r.command(context, "events", fmt.Sprintf("--interval=%ds", int(interval.Seconds())), id)
+	rd, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		rd.Close()
+		return nil, err
+	}
+	var (
+		dec = json.NewDecoder(rd)
+		c   = make(chan *runc.Event, 128)
+	)
+	go func() {
+		defer func() {
+			close(c)
+			rd.Close()
+			Monitor.Wait(cmd, ec)
+		}()
+		for {
+			var e runc.Event
+			if err := dec.Decode(&e); err != nil {
+				if err == io.EOF {
+					return
+				}
+				e = runc.Event{
+					Type: "error",
+					Err:  err,
+				}
+			}
+			c <- &e
+		}
+	}()
+	return c, nil
+}
+
+// Ps lists all the processes inside the container returning their pids
+func (r *Runsc) Ps(context context.Context, id string) ([]int, error) {
+	data, err := cmdOutput(r.command(context, "ps", "--format", "json", id), true)
+	if err != nil {
+		return nil, fmt.Errorf("%s: %s", err, data)
+	}
+	var pids []int
+	if err := json.Unmarshal(data, &pids); err != nil {
+		return nil, err
+	}
+	return pids, nil
+}
+
+// Top lists all the processes inside the container returning the full ps data
+func (r *Runsc) Top(context context.Context, id string) (*runc.TopResults, error) {
+	data, err := cmdOutput(r.command(context, "ps", "--format", "table", id), true)
+	if err != nil {
+		return nil, fmt.Errorf("%s: %s", err, data)
+	}
+
+	topResults, err := runc.ParsePSOutput(data)
+	if err != nil {
+		return nil, fmt.Errorf("%s: ", err)
+	}
+	return topResults, nil
+}
+
+func (r *Runsc) args() []string {
+	var args []string
+	if r.Root != "" {
+		args = append(args, fmt.Sprintf("--root=%s", r.Root))
+	}
+	if r.Log != "" {
+		args = append(args, fmt.Sprintf("--log=%s", r.Log))
+	}
+	if r.LogFormat != "" {
+		args = append(args, fmt.Sprintf("--log-format=%s", r.LogFormat))
+	}
+	for k, v := range r.Config {
+		args = append(args, fmt.Sprintf("--%s=%s", k, v))
+	}
+	return args
+}
+
+// runOrError will run the provided command.  If an error is
+// encountered and neither Stdout or Stderr was set the error and the
+// stderr of the command will be returned in the format of <error>:
+// <stderr>
+func (r *Runsc) runOrError(cmd *exec.Cmd) error {
+	if cmd.Stdout != nil || cmd.Stderr != nil {
+		ec, err := Monitor.Start(cmd)
+		if err != nil {
+			return err
+		}
+		status, err := Monitor.Wait(cmd, ec)
+		if err == nil && status != 0 {
+			err = fmt.Errorf("%s did not terminate sucessfully", cmd.Args[0])
+		}
+		return err
+	}
+	data, err := cmdOutput(cmd, true)
+	if err != nil {
+		return fmt.Errorf("%s: %s", err, data)
+	}
+	return nil
+}
+
+func (r *Runsc) command(context context.Context, args ...string) *exec.Cmd {
+	command := r.Command
+	if command == "" {
+		command = DefaultCommand
+	}
+	cmd := exec.CommandContext(context, command, append(r.args(), args...)...)
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Setpgid: r.Setpgid,
+	}
+	if r.PdeathSignal != 0 {
+		cmd.SysProcAttr.Pdeathsig = r.PdeathSignal
+	}
+
+	return cmd
+}
+
+func cmdOutput(cmd *exec.Cmd, combined bool) ([]byte, error) {
+	b := getBuf()
+	defer putBuf(b)
+
+	cmd.Stdout = b
+	if combined {
+		cmd.Stderr = b
+	}
+	ec, err := Monitor.Start(cmd)
+	if err != nil {
+		return nil, err
+	}
+
+	status, err := Monitor.Wait(cmd, ec)
+	if err == nil && status != 0 {
+		err = fmt.Errorf("%s did not terminate sucessfully", cmd.Args[0])
+	}
+
+	return b.Bytes(), err
+}