execution: add shim runtime

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>
This commit is contained in:
Kenfe-Mickael Laventure 2017-01-12 10:32:09 -08:00
parent 37a113f9fb
commit 5b40adf9af
9 changed files with 852 additions and 21 deletions

View file

@ -21,6 +21,7 @@ import (
"github.com/docker/containerd/events"
"github.com/docker/containerd/execution"
"github.com/docker/containerd/execution/executors/oci"
"github.com/docker/containerd/execution/executors/shim"
"github.com/docker/containerd/log"
metrics "github.com/docker/go-metrics"
"github.com/sirupsen/logrus"
@ -103,6 +104,16 @@ high performance container runtime
return err
}
// Get events publisher
nec, err := getNATSPublisher(context)
if err != nil {
return err
}
defer nec.Close()
ctx := log.WithModule(gocontext.Background(), "containerd")
ctx = log.WithModule(ctx, "execution")
ctx = events.WithPoster(ctx, events.GetNATSPoster(nec))
var (
executor execution.Executor
runtime = context.GlobalString("runtime")
@ -113,20 +124,20 @@ high performance container runtime
if err != nil {
return err
}
case "shim":
root := filepath.Join(context.GlobalString("root"), "shim")
err = os.Mkdir(root, 0700)
if err != nil && !os.IsExist(err) {
return err
}
executor, err = shim.New(log.WithModule(ctx, "shim"), root, "containerd-shim", "runc", nil)
if err != nil {
return err
}
default:
return fmt.Errorf("oci: runtime %q not implemented", runtime)
}
// Get events publisher
nec, err := getNATSPublisher(context)
if err != nil {
return err
}
defer nec.Close()
ctx := log.WithModule(gocontext.Background(), "containerd")
ctx = log.WithModule(ctx, "execution")
ctx = events.WithPoster(ctx, events.GetNATSPoster(nec))
execService, err := execution.New(ctx, executor)
if err != nil {
return err

View file

@ -16,12 +16,11 @@ func NewContainer(stateRoot, id, bundle string) (*Container, error) {
}, nil
}
func LoadContainer(dir StateDir, id, bundle string, status Status, initPid int64) *Container {
func LoadContainer(dir StateDir, id, bundle string, status Status) *Container {
return &Container{
id: id,
stateDir: dir,
bundle: bundle,
initPid: initPid,
status: status,
processes: make(map[string]Process),
}

View file

@ -3,5 +3,8 @@ package execution
import "fmt"
var (
ErrProcessNotFound = fmt.Errorf("process not found")
ErrProcessNotFound = fmt.Errorf("process not found")
ErrProcessNotExited = fmt.Errorf("process has not exited")
ErrContainerNotFound = fmt.Errorf("container not found")
ErrContainerExists = fmt.Errorf("container already exists")
)

View file

@ -28,7 +28,6 @@ type Executor interface {
Create(ctx context.Context, id string, o CreateOpts) (*Container, error)
Pause(context.Context, *Container) error
Resume(context.Context, *Container) error
Status(context.Context, *Container) (Status, error)
List(context.Context) ([]*Container, error)
Load(ctx context.Context, id string) (*Container, error)
Delete(context.Context, *Container) error

View file

@ -122,7 +122,6 @@ func (r *OCIRuntime) load(runcC *runc.Container) (*execution.Container, error) {
runcC.ID,
runcC.Bundle,
execution.Status(runcC.Status),
int64(runcC.Pid),
)
dirs, err := container.StateDir().Processes()

View file

@ -0,0 +1,381 @@
package shim
import (
"context"
"encoding/json"
"io/ioutil"
"os"
"os/exec"
"path/filepath"
"strconv"
"sync"
"syscall"
"github.com/docker/containerd/execution"
"github.com/docker/containerd/log"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"golang.org/x/sys/unix"
runc "github.com/crosbymichael/go-runc"
starttime "github.com/opencontainers/runc/libcontainer/system"
)
type newProcessOpts struct {
shimBinary string
runtime string
runtimeArgs []string
container *execution.Container
exec bool
execution.StartProcessOpts
}
func newProcess(ctx context.Context, o newProcessOpts) (*process, error) {
procStateDir, err := o.container.StateDir().NewProcess(o.ID)
if err != nil {
return nil, err
}
exitPipe, controlPipe, err := getControlPipes(procStateDir)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
exitPipe.Close()
controlPipe.Close()
}
}()
cmd, err := newShim(o, procStateDir)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
cmd.Process.Kill()
cmd.Wait()
}
}()
abortCh := make(chan syscall.WaitStatus, 1)
go func() {
var shimStatus syscall.WaitStatus
if err := cmd.Wait(); err != nil {
shimStatus = execution.UnknownStatusCode
} else {
shimStatus = cmd.ProcessState.Sys().(syscall.WaitStatus)
}
abortCh <- shimStatus
close(abortCh)
}()
process := &process{
root: procStateDir,
id: o.ID,
exitChan: make(chan struct{}),
exitPipe: exitPipe,
controlPipe: controlPipe,
}
pid, stime, status, err := waitForPid(ctx, abortCh, procStateDir)
if err != nil {
return nil, err
}
process.pid = int64(pid)
process.status = status
process.startTime = stime
return process, nil
}
func loadProcess(root, id string) (*process, error) {
pid, err := runc.ReadPidFile(filepath.Join(root, pidFilename))
if err != nil {
return nil, err
}
stime, err := ioutil.ReadFile(filepath.Join(root, startTimeFilename))
if err != nil {
return nil, err
}
path := filepath.Join(root, exitPipeFilename)
exitPipe, err := os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
exitPipe.Close()
}
}()
path = filepath.Join(root, controlPipeFilename)
controlPipe, err := os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
controlPipe.Close()
}
}()
p := &process{
root: root,
id: id,
pid: int64(pid),
exitChan: make(chan struct{}),
exitPipe: exitPipe,
controlPipe: controlPipe,
startTime: string(stime),
// TODO: status may need to be stored on disk to handle
// Created state for init (i.e. a Start is needed to run the
// container)
status: execution.Running,
}
markAsStopped := func(p *process) (*process, error) {
p.setStatus(execution.Stopped)
return p, nil
}
if err = syscall.Kill(pid, 0); err != nil {
if err == syscall.ESRCH {
return markAsStopped(p)
}
return nil, err
}
cstime, err := starttime.GetProcessStartTime(pid)
if err != nil {
if os.IsNotExist(err) {
return markAsStopped(p)
}
return nil, err
}
if p.startTime != cstime {
return markAsStopped(p)
}
return p, nil
}
type process struct {
root string
id string
pid int64
exitChan chan struct{}
exitPipe *os.File
controlPipe *os.File
startTime string
status execution.Status
ctx context.Context
mu sync.Mutex
}
func (p *process) ID() string {
return p.id
}
func (p *process) Pid() int64 {
return p.pid
}
func (p *process) Wait() (uint32, error) {
<-p.exitChan
log.G(p.ctx).WithFields(logrus.Fields{"process-id": p.ID(), "pid": p.pid}).
Debugf("wait is over")
// Cleanup those fds
p.exitPipe.Close()
p.controlPipe.Close()
// If the container process is still alive, it means the shim crashed
// and the child process had updated it PDEATHSIG to something
// else than SIGKILL. Or that epollCtl failed
if p.isAlive() {
err := syscall.Kill(int(p.pid), syscall.SIGKILL)
if err != nil {
return execution.UnknownStatusCode, errors.Wrap(err, "failed to kill process")
}
return uint32(128 + int(syscall.SIGKILL)), nil
}
data, err := ioutil.ReadFile(filepath.Join(p.root, exitStatusFilename))
if err != nil {
return execution.UnknownStatusCode, errors.Wrap(err, "failed to read process exit status")
}
if len(data) == 0 {
return execution.UnknownStatusCode, errors.New(execution.ErrProcessNotExited.Error())
}
status, err := strconv.Atoi(string(data))
if err != nil {
return execution.UnknownStatusCode, errors.Wrapf(err, "failed to parse exit status")
}
p.setStatus(execution.Stopped)
return uint32(status), nil
}
func (p *process) Signal(sig os.Signal) error {
err := syscall.Kill(int(p.pid), sig.(syscall.Signal))
if err != nil {
return errors.Wrap(err, "failed to signal process")
}
return nil
}
func (p *process) Status() execution.Status {
p.mu.Lock()
s := p.status
p.mu.Unlock()
return s
}
func (p *process) setStatus(s execution.Status) {
p.mu.Lock()
p.status = s
p.mu.Unlock()
}
func (p *process) isAlive() bool {
if err := syscall.Kill(int(p.pid), 0); err != nil {
if err == syscall.ESRCH {
return false
}
log.G(p.ctx).WithFields(logrus.Fields{"process-id": p.ID(), "pid": p.pid}).
Warnf("kill(0) failed: %v", err)
return false
}
// check that we have the same startttime
stime, err := starttime.GetProcessStartTime(int(p.pid))
if err != nil {
if os.IsNotExist(err) {
return false
}
log.G(p.ctx).WithFields(logrus.Fields{"process-id": p.ID(), "pid": p.pid}).
Warnf("failed to get process start time: %v", err)
return false
}
if p.startTime != stime {
return false
}
return true
}
func waitForPid(ctx context.Context, abortCh chan syscall.WaitStatus, root string) (pid int, stime string, status execution.Status, err error) {
status = execution.Unknown
for {
select {
case <-ctx.Done():
return
case wait := <-abortCh:
if wait.Signaled() {
err = errors.Errorf("shim died prematurarily: %v", wait.Signal())
return
}
err = errors.Errorf("shim exited prematurarily with exit code %v", wait.ExitStatus())
return
default:
}
pid, err = runc.ReadPidFile(filepath.Join(root, pidFilename))
if err == nil {
break
} else if !os.IsNotExist(err) {
return
}
}
status = execution.Created
stime, err = starttime.GetProcessStartTime(pid)
switch {
case os.IsNotExist(err):
status = execution.Stopped
case err != nil:
return
default:
var b []byte
path := filepath.Join(root, startTimeFilename)
b, err = ioutil.ReadFile(path)
switch {
case os.IsNotExist(err):
err = ioutil.WriteFile(path, []byte(stime), 0600)
if err != nil {
return
}
case err != nil:
err = errors.Wrapf(err, "failed to get start time for pid %d", pid)
return
case string(b) != stime:
status = execution.Stopped
}
}
return pid, stime, status, nil
}
func newShim(o newProcessOpts, workDir string) (*exec.Cmd, error) {
cmd := exec.Command(o.shimBinary, o.container.ID(), o.container.Bundle(), o.runtime)
cmd.Dir = workDir
cmd.SysProcAttr = &syscall.SysProcAttr{
Setpgid: true,
}
state := processState{
Process: o.Spec,
Exec: o.exec,
Stdin: o.Stdin,
Stdout: o.Stdout,
Stderr: o.Stderr,
RuntimeArgs: o.runtimeArgs,
NoPivotRoot: false,
CheckpointPath: "",
RootUID: int(o.Spec.User.UID),
RootGID: int(o.Spec.User.GID),
}
f, err := os.Create(filepath.Join(workDir, "process.json"))
if err != nil {
return nil, errors.Wrapf(err, "failed to create shim's process.json for container %s", o.container.ID())
}
defer f.Close()
if err := json.NewEncoder(f).Encode(state); err != nil {
return nil, errors.Wrapf(err, "failed to create shim's processState for container %s", o.container.ID())
}
if err := cmd.Start(); err != nil {
return nil, errors.Wrapf(err, "failed to start shim for container %s", o.container.ID())
}
return cmd, nil
}
func getControlPipes(root string) (exitPipe *os.File, controlPipe *os.File, err error) {
path := filepath.Join(root, exitPipeFilename)
if err = unix.Mkfifo(path, 0700); err != nil {
return exitPipe, controlPipe, errors.Wrap(err, "failed to create shim exit fifo")
}
if exitPipe, err = os.OpenFile(path, syscall.O_RDONLY|syscall.O_NONBLOCK, 0); err != nil {
return exitPipe, controlPipe, errors.Wrap(err, "failed to open shim exit fifo")
}
path = filepath.Join(root, controlPipeFilename)
if err = unix.Mkfifo(path, 0700); err != nil {
return exitPipe, controlPipe, errors.Wrap(err, "failed to create shim control fifo")
}
if controlPipe, err = os.OpenFile(path, syscall.O_RDWR|syscall.O_NONBLOCK, 0); err != nil {
return exitPipe, controlPipe, errors.Wrap(err, "failed to open shim control fifo")
}
return exitPipe, controlPipe, nil
}

View file

@ -0,0 +1,420 @@
package shim
import (
"context"
"encoding/json"
"io/ioutil"
"os"
"os/exec"
"path/filepath"
"sync"
"syscall"
"github.com/docker/containerd/execution"
"github.com/docker/containerd/log"
"github.com/opencontainers/runtime-spec/specs-go"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
const (
DefaultShimBinary = "containerd-shim"
pidFilename = "pid"
startTimeFilename = "starttime"
exitPipeFilename = "exit"
controlPipeFilename = "control"
initProcessID = "init"
exitStatusFilename = "exitStatus"
)
func New(ctx context.Context, root, shim, runtime string, runtimeArgs []string) (*ShimRuntime, error) {
fd, err := syscall.EpollCreate1(0)
if err != nil {
return nil, errors.Wrap(err, "epollcreate1 failed")
}
s := &ShimRuntime{
ctx: ctx,
epollFd: fd,
root: root,
binaryName: shim,
runtime: runtime,
runtimeArgs: runtimeArgs,
exitChannels: make(map[int]*process),
containers: make(map[string]*execution.Container),
}
s.loadContainers()
go s.monitor()
return s, nil
}
type ShimRuntime struct {
ctx context.Context
mutex sync.Mutex
exitChannels map[int]*process
containers map[string]*execution.Container
epollFd int
root string
binaryName string
runtime string
runtimeArgs []string
}
type ProcessOpts struct {
Bundle string
Terminal bool
Stdin string
Stdout string
Stderr string
}
type processState struct {
specs.Process
Exec bool `json:"exec"`
Stdin string `json:"containerdStdin"`
Stdout string `json:"containerdStdout"`
Stderr string `json:"containerdStderr"`
RuntimeArgs []string `json:"runtimeArgs"`
NoPivotRoot bool `json:"noPivotRoot"`
CheckpointPath string `json:"checkpoint"`
RootUID int `json:"rootUID"`
RootGID int `json:"rootGID"`
}
func (s *ShimRuntime) Create(ctx context.Context, id string, o execution.CreateOpts) (*execution.Container, error) {
log.G(s.ctx).WithFields(logrus.Fields{"container-id": id, "options": o}).Debug("Create()")
if s.getContainer(id) != nil {
return nil, execution.ErrContainerExists
}
container, err := execution.NewContainer(s.root, id, o.Bundle)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
container.StateDir().Delete()
}
}()
err = ioutil.WriteFile(filepath.Join(string(container.StateDir()), "bundle"), []byte(o.Bundle), 0600)
if err != nil {
return nil, errors.Wrap(err, "failed to save bundle path to disk")
}
// extract Process spec from bundle's config.json
var spec specs.Spec
f, err := os.Open(filepath.Join(o.Bundle, "config.json"))
if err != nil {
return nil, errors.Wrap(err, "failed to open config.json")
}
defer f.Close()
if err := json.NewDecoder(f).Decode(&spec); err != nil {
return nil, errors.Wrap(err, "failed to decode container OCI specs")
}
processOpts := newProcessOpts{
shimBinary: s.binaryName,
runtime: s.runtime,
runtimeArgs: s.runtimeArgs,
container: container,
exec: false,
StartProcessOpts: execution.StartProcessOpts{
ID: initProcessID,
Spec: spec.Process,
Console: o.Console,
Stdin: o.Stdin,
Stdout: o.Stdout,
Stderr: o.Stderr,
},
}
process, err := newProcess(ctx, processOpts)
if err != nil {
return nil, err
}
process.ctx = log.WithModule(log.WithModule(s.ctx, "container"), id)
s.monitorProcess(process)
container.AddProcess(process, true)
s.addContainer(container)
return container, nil
}
func (s *ShimRuntime) Start(ctx context.Context, c *execution.Container) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c}).Debug("Start()")
cmd := exec.CommandContext(ctx, s.runtime, append(s.runtimeArgs, "start", c.ID())...)
out, err := cmd.CombinedOutput()
if err != nil {
return errors.Wrapf(err, "'%s start' failed with output: %v", s.runtime, string(out))
}
return nil
}
func (s *ShimRuntime) List(ctx context.Context) ([]*execution.Container, error) {
log.G(s.ctx).Debug("List()")
containers := make([]*execution.Container, 0)
s.mutex.Lock()
for _, c := range s.containers {
containers = append(containers, c)
}
s.mutex.Unlock()
return containers, nil
}
func (s *ShimRuntime) Load(ctx context.Context, id string) (*execution.Container, error) {
log.G(s.ctx).WithFields(logrus.Fields{"container-id": id}).Debug("Start()")
s.mutex.Lock()
c, ok := s.containers[id]
s.mutex.Unlock()
if !ok {
return nil, errors.New(execution.ErrContainerNotFound.Error())
}
return c, nil
}
func (s *ShimRuntime) Delete(ctx context.Context, c *execution.Container) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c}).Debug("Delete()")
if c.Status() != execution.Stopped {
return errors.Errorf("cannot delete a container in the '%s' state", c.Status())
}
c.StateDir().Delete()
s.removeContainer(c)
return nil
}
func (s *ShimRuntime) Pause(ctx context.Context, c *execution.Container) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c}).Debug("Pause()")
cmd := exec.CommandContext(ctx, s.runtime, append(s.runtimeArgs, "pause", c.ID())...)
out, err := cmd.CombinedOutput()
if err != nil {
return errors.Wrapf(err, "'%s pause' failed with output: %v", s.runtime, string(out))
}
return nil
}
func (s *ShimRuntime) Resume(ctx context.Context, c *execution.Container) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c}).Debug("Resume()")
cmd := exec.CommandContext(ctx, s.runtime, append(s.runtimeArgs, "resume", c.ID())...)
out, err := cmd.CombinedOutput()
if err != nil {
return errors.Wrapf(err, "'%s resume' failed with output: %v", s.runtime, string(out))
}
return nil
}
func (s *ShimRuntime) StartProcess(ctx context.Context, c *execution.Container, o execution.StartProcessOpts) (p execution.Process, err error) {
log.G(s.ctx).WithFields(logrus.Fields{"container": c, "options": o}).Debug("StartProcess()")
processOpts := newProcessOpts{
shimBinary: s.binaryName,
runtime: s.runtime,
runtimeArgs: s.runtimeArgs,
container: c,
exec: true,
StartProcessOpts: o,
}
process, err := newProcess(ctx, processOpts)
if err != nil {
return nil, err
}
process.status = execution.Running
s.monitorProcess(process)
c.AddProcess(process, false)
return process, nil
}
func (s *ShimRuntime) SignalProcess(ctx context.Context, c *execution.Container, id string, sig os.Signal) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c, "process-id": id, "signal": sig}).
Debug("SignalProcess()")
process := c.GetProcess(id)
if process == nil {
return errors.Errorf("no such process %s", id)
}
err := syscall.Kill(int(process.Pid()), sig.(syscall.Signal))
if err != nil {
return errors.Wrapf(err, "failed to send %v signal to process %v", sig, process.Pid())
}
return err
}
func (s *ShimRuntime) DeleteProcess(ctx context.Context, c *execution.Container, id string) error {
log.G(s.ctx).WithFields(logrus.Fields{"container": c, "process-id": id}).
Debug("DeleteProcess()")
c.RemoveProcess(id)
return c.StateDir().DeleteProcess(id)
}
//
//
//
func (s *ShimRuntime) monitor() {
var events [128]syscall.EpollEvent
for {
n, err := syscall.EpollWait(s.epollFd, events[:], -1)
if err != nil {
if err == syscall.EINTR {
continue
}
log.G(s.ctx).Error("epollwait failed:", err)
}
for i := 0; i < n; i++ {
fd := int(events[i].Fd)
s.mutex.Lock()
p := s.exitChannels[fd]
delete(s.exitChannels, fd)
s.mutex.Unlock()
if err = syscall.EpollCtl(s.epollFd, syscall.EPOLL_CTL_DEL, fd, &syscall.EpollEvent{
Events: syscall.EPOLLHUP,
Fd: int32(fd),
}); err != nil {
log.G(s.ctx).Error("epollctl deletion failed:", err)
}
close(p.exitChan)
}
}
}
func (s *ShimRuntime) addContainer(c *execution.Container) {
s.mutex.Lock()
s.containers[c.ID()] = c
s.mutex.Unlock()
}
func (s *ShimRuntime) removeContainer(c *execution.Container) {
s.mutex.Lock()
delete(s.containers, c.ID())
s.mutex.Unlock()
}
func (s *ShimRuntime) getContainer(id string) *execution.Container {
s.mutex.Lock()
c := s.containers[id]
s.mutex.Unlock()
return c
}
// monitorProcess adds a process to the list of monitored process if
// we fail to do so, we closed the exitChan channel used by Wait().
// Since service always call on Wait() for generating "exit" events,
// this will ensure the process gets killed
func (s *ShimRuntime) monitorProcess(p *process) {
if p.status == execution.Stopped {
close(p.exitChan)
return
}
fd := int(p.exitPipe.Fd())
event := syscall.EpollEvent{
Fd: int32(fd),
Events: syscall.EPOLLHUP,
}
s.mutex.Lock()
s.exitChannels[fd] = p
s.mutex.Unlock()
if err := syscall.EpollCtl(s.epollFd, syscall.EPOLL_CTL_ADD, fd, &event); err != nil {
s.mutex.Lock()
delete(s.exitChannels, fd)
s.mutex.Unlock()
close(p.exitChan)
return
}
// TODO: take care of the OOM handler
}
func (s *ShimRuntime) unmonitorProcess(p *process) {
s.mutex.Lock()
for fd, proc := range s.exitChannels {
if proc == p {
delete(s.exitChannels, fd)
break
}
}
s.mutex.Unlock()
}
func (s *ShimRuntime) loadContainers() {
cs, err := ioutil.ReadDir(s.root)
if err != nil {
log.G(s.ctx).WithField("statedir", s.root).
Warn("failed to load containers, state dir cannot be listed:", err)
return
}
for _, c := range cs {
if !c.IsDir() {
continue
}
stateDir, err := execution.LoadStateDir(s.root, c.Name())
if err != nil {
// We should never fail the above call unless someone
// delete the directory while we're loading
log.G(s.ctx).WithFields(logrus.Fields{"container": c.Name(), "statedir": s.root}).
Warn("failed to load container statedir:", err)
continue
}
bundle, err := ioutil.ReadFile(filepath.Join(string(stateDir), "bundle"))
if err != nil {
log.G(s.ctx).WithField("container", c.Name()).
Warn("failed to load container bundle path:", err)
continue
}
container := execution.LoadContainer(stateDir, c.Name(), string(bundle), execution.Unknown)
s.addContainer(container)
processDirs, err := stateDir.Processes()
if err != nil {
log.G(s.ctx).WithField("container", c.Name()).
Warn("failed to retrieve container processes:", err)
continue
}
for _, procStateRoot := range processDirs {
id := filepath.Base(procStateRoot)
proc, err := loadProcess(procStateRoot, id)
if err != nil {
log.G(s.ctx).WithFields(logrus.Fields{"container": c.Name(), "process": id}).
Warn("failed to load process:", err)
s.removeContainer(container)
for _, p := range container.Processes() {
s.unmonitorProcess(p.(*process))
}
break
}
proc.ctx = log.WithModule(log.WithModule(s.ctx, "container"), container.ID())
container.AddProcess(proc, proc.ID() == initProcessID)
s.monitorProcess(proc)
}
}
}

View file

@ -4,32 +4,46 @@ import (
"io/ioutil"
"os"
"path/filepath"
"github.com/pkg/errors"
)
const processesDirName = "processes"
type StateDir string
func LoadStateDir(root, id string) (StateDir, error) {
path := filepath.Join(root, id)
if _, err := os.Stat(path); err != nil {
return "", errors.Wrap(err, "could not find container statedir")
}
return StateDir(path), nil
}
func NewStateDir(root, id string) (StateDir, error) {
path := filepath.Join(root, id)
if err := os.Mkdir(path, 0700); err != nil {
return "", err
return "", errors.Wrap(err, "could not create container statedir")
}
if err := os.Mkdir(StateDir(path).processesDir(), 0700); err != nil {
os.RemoveAll(path)
return "", err
return "", errors.Wrap(err, "could not create processes statedir")
}
return StateDir(path), nil
}
func (s StateDir) Delete() error {
return os.RemoveAll(string(s))
err := os.RemoveAll(string(s))
if err != nil {
return errors.Wrapf(err, "failed to remove statedir %s", string(s))
}
return nil
}
func (s StateDir) NewProcess(id string) (dir string, err error) {
dir = filepath.Join(s.processesDir(), id)
if err = os.Mkdir(dir, 0700); err != nil {
return "", err
return "", errors.Wrap(err, "could not create process statedir")
}
return dir, nil
@ -40,14 +54,18 @@ func (s StateDir) ProcessDir(id string) string {
}
func (s StateDir) DeleteProcess(id string) error {
return os.RemoveAll(filepath.Join(s.processesDir(), id))
err := os.RemoveAll(filepath.Join(s.processesDir(), id))
if err != nil {
return errors.Wrapf(err, "failed to remove process %d statedir", id)
}
return nil
}
func (s StateDir) Processes() ([]string, error) {
procsDir := s.processesDir()
dirs, err := ioutil.ReadDir(procsDir)
if err != nil {
return nil, err
return nil, errors.Wrap(err, "could not list processes statedir")
}
paths := make([]string, 0)

View file

@ -8,6 +8,7 @@ const (
Running Status = "running"
Stopped Status = "stopped"
Deleted Status = "deleted"
Unknown Status = "unknown"
UnknownStatusCode = 255
)