Runtime v2

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This commit is contained in:
Michael Crosby
2018-07-09 13:27:52 -04:00
parent 6de11ab973
commit da1b5470cd
78 changed files with 9836 additions and 652 deletions

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/*
Copyright The containerd Authors.
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
http://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 options

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syntax = "proto3";
package containerd.runc.v1;
import weak "gogoproto/gogo.proto";
option go_package = "github.com/containerd/containerd/runtime/v2/runc/options;options";
message Options {
bool no_pivot_root = 1;
bool open_tcp = 2;
bool external_unix_sockets = 3;
bool terminal = 4;
bool file_locks = 5;
repeated string empty_namespaces = 6;
string cgroups_mode = 7;
bool no_new_keyring = 8;
string shim_cgroup = 9;
uint32 io_uid = 10;
uint32 io_gid = 11;
string binary_name = 12;
string root = 13;
string criu_path = 14;
bool systemd_cgroup = 15;
}
message CheckpointOptions {
bool exit = 1;
bool open_tcp = 2;
bool external_unix_sockets = 3;
bool terminal = 4;
bool file_locks = 5;
repeated string empty_namespaces = 6;
string cgroups_mode = 7;
}
message ProcessDetails {
string exec_id = 1;
}

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runtime/v2/runc/service.go Normal file
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// +build linux
/*
Copyright The containerd Authors.
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
http://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 runc
import (
"context"
"io/ioutil"
"os"
"path/filepath"
"sync"
"time"
"github.com/containerd/cgroups"
"github.com/containerd/console"
eventstypes "github.com/containerd/containerd/api/events"
"github.com/containerd/containerd/api/types/task"
"github.com/containerd/containerd/errdefs"
"github.com/containerd/containerd/events"
"github.com/containerd/containerd/mount"
"github.com/containerd/containerd/namespaces"
"github.com/containerd/containerd/runtime"
rproc "github.com/containerd/containerd/runtime/proc"
"github.com/containerd/containerd/runtime/v1/linux/proc"
"github.com/containerd/containerd/runtime/v2/runc/options"
"github.com/containerd/containerd/runtime/v2/shim"
taskAPI "github.com/containerd/containerd/runtime/v2/task"
runcC "github.com/containerd/go-runc"
"github.com/containerd/typeurl"
ptypes "github.com/gogo/protobuf/types"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"golang.org/x/sys/unix"
)
var (
empty = &ptypes.Empty{}
bufPool = sync.Pool{
New: func() interface{} {
buffer := make([]byte, 32<<10)
return &buffer
},
}
)
var _ = (taskAPI.TaskService)(&service{})
// New returns a new shim service that can be used via GRPC
func New(ctx context.Context, id string, publisher events.Publisher) (shim.Shim, error) {
s := &service{
id: id,
context: ctx,
processes: make(map[string]rproc.Process),
events: make(chan interface{}, 128),
ec: shim.Default.Subscribe(),
}
go s.processExits()
runcC.Monitor = shim.Default
if err := s.initPlatform(); err != nil {
return nil, errors.Wrap(err, "failed to initialized platform behavior")
}
go s.forward(publisher)
return s, nil
}
// service is the shim implementation of a remote shim over GRPC
type service struct {
mu sync.Mutex
context context.Context
processes map[string]rproc.Process
events chan interface{}
platform rproc.Platform
ec chan runcC.Exit
id string
// Filled by Create()
bundle string
cg cgroups.Cgroup
}
func (s *service) Cleanup(ctx context.Context) (*taskAPI.DeleteResponse, error) {
path, err := os.Getwd()
if err != nil {
return nil, err
}
ns, err := namespaces.NamespaceRequired(ctx)
if err != nil {
return nil, err
}
runtime, _ := s.readRuntime(path)
if runtime != "" {
r := proc.NewRunc(proc.RuncRoot, path, ns, runtime, "", false)
if err := r.Delete(ctx, s.id, &runcC.DeleteOpts{
Force: true,
}); err != nil {
logrus.WithError(err).Warn("runc delete")
}
}
if err := mount.UnmountAll(filepath.Join(path, "rootfs"), 0); err != nil {
logrus.WithError(err).Warn("failed to cleanup rootfs mount")
}
return &taskAPI.DeleteResponse{
ExitedAt: time.Now(),
ExitStatus: 128 + uint32(unix.SIGKILL),
}, nil
}
func (s *service) readRuntime(path string) (string, error) {
data, err := ioutil.ReadFile(filepath.Join(path, "runtime"))
if err != nil {
return "", err
}
return string(data), nil
}
func (s *service) writeRuntime(path, runtime string) error {
return ioutil.WriteFile(filepath.Join(path, "runtime"), []byte(runtime), 0600)
}
// Create a new initial process and container with the underlying OCI runtime
func (s *service) Create(ctx context.Context, r *taskAPI.CreateTaskRequest) (_ *taskAPI.CreateTaskResponse, err error) {
s.mu.Lock()
defer s.mu.Unlock()
ns, err := namespaces.NamespaceRequired(ctx)
if err != nil {
return nil, errors.Wrap(err, "create namespace")
}
var opts options.Options
if r.Options != nil {
v, err := typeurl.UnmarshalAny(r.Options)
if err != nil {
return nil, err
}
opts = *v.(*options.Options)
}
var mounts []proc.Mount
for _, m := range r.Rootfs {
mounts = append(mounts, proc.Mount{
Type: m.Type,
Source: m.Source,
Target: m.Target,
Options: m.Options,
})
}
config := &proc.CreateConfig{
ID: r.ID,
Bundle: r.Bundle,
Runtime: opts.BinaryName,
Rootfs: mounts,
Terminal: r.Terminal,
Stdin: r.Stdin,
Stdout: r.Stdout,
Stderr: r.Stderr,
Checkpoint: r.Checkpoint,
ParentCheckpoint: r.ParentCheckpoint,
Options: r.Options,
}
if err := s.writeRuntime(r.Bundle, opts.BinaryName); err != nil {
return nil, err
}
rootfs := filepath.Join(r.Bundle, "rootfs")
defer func() {
if err != nil {
if err2 := mount.UnmountAll(rootfs, 0); err2 != nil {
logrus.WithError(err2).Warn("failed to cleanup rootfs mount")
}
}
}()
for _, rm := range mounts {
m := &mount.Mount{
Type: rm.Type,
Source: rm.Source,
Options: rm.Options,
}
if err := m.Mount(rootfs); err != nil {
return nil, errors.Wrapf(err, "failed to mount rootfs component %v", m)
}
}
process, err := newInit(
ctx,
r.Bundle,
filepath.Join(r.Bundle, "work"),
ns,
s.platform,
config,
&opts,
)
if err != nil {
return nil, errdefs.ToGRPC(err)
}
if err := process.Create(ctx, config); err != nil {
return nil, errdefs.ToGRPC(err)
}
// save the main task id and bundle to the shim for additional requests
s.id = r.ID
s.bundle = r.Bundle
pid := process.Pid()
if pid > 0 {
cg, err := cgroups.Load(cgroups.V1, cgroups.PidPath(pid))
if err != nil {
logrus.WithError(err).Errorf("loading cgroup for %d", pid)
}
s.cg = cg
}
s.processes[r.ID] = process
return &taskAPI.CreateTaskResponse{
Pid: uint32(pid),
}, nil
}
// Start a process
func (s *service) Start(ctx context.Context, r *taskAPI.StartRequest) (*taskAPI.StartResponse, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[r.ID]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "process %s", r.ID)
}
if err := p.Start(ctx); err != nil {
return nil, err
}
if s.cg == nil && p.Pid() > 0 {
cg, err := cgroups.Load(cgroups.V1, cgroups.PidPath(p.Pid()))
if err != nil {
logrus.WithError(err).Errorf("loading cgroup for %d", p.Pid())
}
s.cg = cg
}
return &taskAPI.StartResponse{
ID: p.ID(),
Pid: uint32(p.Pid()),
}, nil
}
// Delete the initial process and container
func (s *service) Delete(ctx context.Context, r *taskAPI.DeleteRequest) (*taskAPI.DeleteResponse, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[r.ID]
if p == nil {
return nil, errors.Wrapf(errdefs.ErrNotFound, "process %s", r.ID)
}
if err := p.Delete(ctx); err != nil {
return nil, err
}
delete(s.processes, r.ID)
if r.ID == s.id && s.platform != nil {
s.platform.Close()
}
return &taskAPI.DeleteResponse{
ExitStatus: uint32(p.ExitStatus()),
ExitedAt: p.ExitedAt(),
Pid: uint32(p.Pid()),
}, nil
}
// Exec an additional process inside the container
func (s *service) Exec(ctx context.Context, r *taskAPI.ExecProcessRequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
if p := s.processes[r.ID]; p != nil {
return nil, errdefs.ToGRPCf(errdefs.ErrAlreadyExists, "id %s", r.ID)
}
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
process, err := p.(*proc.Init).Exec(ctx, s.bundle, &proc.ExecConfig{
ID: r.ID,
Terminal: r.Terminal,
Stdin: r.Stdin,
Stdout: r.Stdout,
Stderr: r.Stderr,
Spec: r.Spec,
})
if err != nil {
return nil, errdefs.ToGRPC(err)
}
s.processes[r.ID] = process
return empty, nil
}
// ResizePty of a process
func (s *service) ResizePty(ctx context.Context, r *taskAPI.ResizePtyRequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
if r.ID == "" {
return nil, errdefs.ToGRPCf(errdefs.ErrInvalidArgument, "id not provided")
}
ws := console.WinSize{
Width: uint16(r.Width),
Height: uint16(r.Height),
}
p := s.processes[r.ID]
if p == nil {
return nil, errors.Errorf("process does not exist %s", r.ID)
}
if err := p.Resize(ws); err != nil {
return nil, errdefs.ToGRPC(err)
}
return empty, nil
}
// State returns runtime state information for a process
func (s *service) State(ctx context.Context, r *taskAPI.StateRequest) (*taskAPI.StateResponse, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[r.ID]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "process id %s", r.ID)
}
st, err := p.Status(ctx)
if err != nil {
return nil, err
}
status := task.StatusUnknown
switch st {
case "created":
status = task.StatusCreated
case "running":
status = task.StatusRunning
case "stopped":
status = task.StatusStopped
case "paused":
status = task.StatusPaused
case "pausing":
status = task.StatusPausing
}
sio := p.Stdio()
return &taskAPI.StateResponse{
ID: p.ID(),
Bundle: s.bundle,
Pid: uint32(p.Pid()),
Status: status,
Stdin: sio.Stdin,
Stdout: sio.Stdout,
Stderr: sio.Stderr,
Terminal: sio.Terminal,
ExitStatus: uint32(p.ExitStatus()),
ExitedAt: p.ExitedAt(),
}, nil
}
// Pause the container
func (s *service) Pause(ctx context.Context, r *ptypes.Empty) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
if err := p.(*proc.Init).Pause(ctx); err != nil {
return nil, err
}
return empty, nil
}
// Resume the container
func (s *service) Resume(ctx context.Context, r *ptypes.Empty) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
if err := p.(*proc.Init).Resume(ctx); err != nil {
return nil, err
}
return empty, nil
}
// Kill a process with the provided signal
func (s *service) Kill(ctx context.Context, r *taskAPI.KillRequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
if r.ID == "" {
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
if err := p.Kill(ctx, r.Signal, r.All); err != nil {
return nil, errdefs.ToGRPC(err)
}
return empty, nil
}
p := s.processes[r.ID]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "process id %s not found", r.ID)
}
if err := p.Kill(ctx, r.Signal, r.All); err != nil {
return nil, errdefs.ToGRPC(err)
}
return empty, nil
}
// Pids returns all pids inside the container
func (s *service) Pids(ctx context.Context, r *taskAPI.PidsRequest) (*taskAPI.PidsResponse, error) {
pids, err := s.getContainerPids(ctx, r.ID)
if err != nil {
return nil, errdefs.ToGRPC(err)
}
var processes []*task.ProcessInfo
for _, pid := range pids {
pInfo := task.ProcessInfo{
Pid: pid,
}
for _, p := range s.processes {
if p.Pid() == int(pid) {
d := &options.ProcessDetails{
ExecID: p.ID(),
}
a, err := typeurl.MarshalAny(d)
if err != nil {
return nil, errors.Wrapf(err, "failed to marshal process %d info", pid)
}
pInfo.Info = a
break
}
}
processes = append(processes, &pInfo)
}
return &taskAPI.PidsResponse{
Processes: processes,
}, nil
}
// CloseIO of a process
func (s *service) CloseIO(ctx context.Context, r *taskAPI.CloseIORequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[r.ID]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "process does not exist %s", r.ID)
}
if stdin := p.Stdin(); stdin != nil {
if err := stdin.Close(); err != nil {
return nil, errors.Wrap(err, "close stdin")
}
}
return empty, nil
}
// Checkpoint the container
func (s *service) Checkpoint(ctx context.Context, r *taskAPI.CheckpointTaskRequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
var opts options.CheckpointOptions
if r.Options != nil {
v, err := typeurl.UnmarshalAny(r.Options)
if err != nil {
return nil, err
}
opts = *v.(*options.CheckpointOptions)
}
if err := p.(*proc.Init).Checkpoint(ctx, &proc.CheckpointConfig{
Path: r.Path,
Exit: opts.Exit,
AllowOpenTCP: opts.OpenTcp,
AllowExternalUnixSockets: opts.ExternalUnixSockets,
AllowTerminal: opts.Terminal,
FileLocks: opts.FileLocks,
EmptyNamespaces: opts.EmptyNamespaces,
}); err != nil {
return nil, errdefs.ToGRPC(err)
}
return empty, nil
}
// Connect returns shim information such as the shim's pid
func (s *service) Connect(ctx context.Context, r *taskAPI.ConnectRequest) (*taskAPI.ConnectResponse, error) {
return &taskAPI.ConnectResponse{
ShimPid: uint32(os.Getpid()),
TaskPid: uint32(s.processes[s.id].Pid()),
}, nil
}
func (s *service) Shutdown(ctx context.Context, r *taskAPI.ShutdownRequest) (*ptypes.Empty, error) {
os.Exit(0)
return empty, nil
}
func (s *service) Stats(ctx context.Context, r *taskAPI.StatsRequest) (*taskAPI.StatsResponse, error) {
s.mu.Lock()
defer s.mu.Unlock()
if s.cg == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrNotFound, "cgroup does not exist")
}
stats, err := s.cg.Stat(cgroups.IgnoreNotExist)
if err != nil {
return nil, err
}
data, err := typeurl.MarshalAny(stats)
if err != nil {
return nil, err
}
return &taskAPI.StatsResponse{
Stats: data,
}, nil
}
// Update a running container
func (s *service) Update(ctx context.Context, r *taskAPI.UpdateTaskRequest) (*ptypes.Empty, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[s.id]
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
if err := p.(*proc.Init).Update(ctx, r.Resources); err != nil {
return nil, errdefs.ToGRPC(err)
}
return empty, nil
}
// Wait for a process to exit
func (s *service) Wait(ctx context.Context, r *taskAPI.WaitRequest) (*taskAPI.WaitResponse, error) {
s.mu.Lock()
p := s.processes[r.ID]
s.mu.Unlock()
if p == nil {
return nil, errdefs.ToGRPCf(errdefs.ErrFailedPrecondition, "container must be created")
}
p.Wait()
return &taskAPI.WaitResponse{
ExitStatus: uint32(p.ExitStatus()),
ExitedAt: p.ExitedAt(),
}, nil
}
func (s *service) processExits() {
for e := range s.ec {
s.checkProcesses(e)
}
}
func (s *service) checkProcesses(e runcC.Exit) {
s.mu.Lock()
defer s.mu.Unlock()
for _, p := range s.processes {
if p.Pid() == e.Pid {
if ip, ok := p.(*proc.Init); ok {
// Ensure all children are killed
if err := ip.KillAll(s.context); err != nil {
logrus.WithError(err).WithField("id", ip.ID()).
Error("failed to kill init's children")
}
}
p.SetExited(e.Status)
s.events <- &eventstypes.TaskExit{
ContainerID: s.id,
ID: p.ID(),
Pid: uint32(e.Pid),
ExitStatus: uint32(e.Status),
ExitedAt: p.ExitedAt(),
}
return
}
}
}
func (s *service) getContainerPids(ctx context.Context, id string) ([]uint32, error) {
s.mu.Lock()
defer s.mu.Unlock()
p := s.processes[s.id]
if p == nil {
return nil, errors.Wrapf(errdefs.ErrFailedPrecondition, "container must be created")
}
ps, err := p.(*proc.Init).Runtime().Ps(ctx, id)
if err != nil {
return nil, err
}
pids := make([]uint32, 0, len(ps))
for _, pid := range ps {
pids = append(pids, uint32(pid))
}
return pids, nil
}
func (s *service) forward(publisher events.Publisher) {
for e := range s.events {
if err := publisher.Publish(s.context, getTopic(s.context, e), e); err != nil {
logrus.WithError(err).Error("post event")
}
}
}
func getTopic(ctx context.Context, e interface{}) string {
switch e.(type) {
case *eventstypes.TaskCreate:
return runtime.TaskCreateEventTopic
case *eventstypes.TaskStart:
return runtime.TaskStartEventTopic
case *eventstypes.TaskOOM:
return runtime.TaskOOMEventTopic
case *eventstypes.TaskExit:
return runtime.TaskExitEventTopic
case *eventstypes.TaskDelete:
return runtime.TaskDeleteEventTopic
case *eventstypes.TaskExecAdded:
return runtime.TaskExecAddedEventTopic
case *eventstypes.TaskExecStarted:
return runtime.TaskExecStartedEventTopic
case *eventstypes.TaskPaused:
return runtime.TaskPausedEventTopic
case *eventstypes.TaskResumed:
return runtime.TaskResumedEventTopic
case *eventstypes.TaskCheckpointed:
return runtime.TaskCheckpointedEventTopic
default:
logrus.Warnf("no topic for type %#v", e)
}
return runtime.TaskUnknownTopic
}
func newInit(ctx context.Context, path, workDir, namespace string, platform rproc.Platform, r *proc.CreateConfig, options *options.Options) (*proc.Init, error) {
rootfs := filepath.Join(path, "rootfs")
runtime := proc.NewRunc(options.Root, path, namespace, options.BinaryName, options.CriuPath, options.SystemdCgroup)
p := proc.New(r.ID, runtime, rproc.Stdio{
Stdin: r.Stdin,
Stdout: r.Stdout,
Stderr: r.Stderr,
Terminal: r.Terminal,
})
p.Bundle = r.Bundle
p.Platform = platform
p.Rootfs = rootfs
p.WorkDir = workDir
p.IoUID = int(options.IoUid)
p.IoGID = int(options.IoGid)
p.NoPivotRoot = options.NoPivotRoot
p.NoNewKeyring = options.NoNewKeyring
return p, nil
}

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/*
Copyright The containerd Authors.
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
http://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 runc
import (
"context"
"io"
"sync"
"syscall"
"github.com/containerd/console"
"github.com/containerd/fifo"
"github.com/pkg/errors"
)
type linuxPlatform struct {
epoller *console.Epoller
}
func (p *linuxPlatform) CopyConsole(ctx context.Context, console console.Console, stdin, stdout, stderr string, wg, cwg *sync.WaitGroup) (console.Console, error) {
if p.epoller == nil {
return nil, errors.New("uninitialized epoller")
}
epollConsole, err := p.epoller.Add(console)
if err != nil {
return nil, err
}
if stdin != "" {
in, err := fifo.OpenFifo(ctx, stdin, syscall.O_RDONLY, 0)
if err != nil {
return nil, err
}
cwg.Add(1)
go func() {
cwg.Done()
p := bufPool.Get().(*[]byte)
defer bufPool.Put(p)
io.CopyBuffer(epollConsole, in, *p)
}()
}
outw, err := fifo.OpenFifo(ctx, stdout, syscall.O_WRONLY, 0)
if err != nil {
return nil, err
}
outr, err := fifo.OpenFifo(ctx, stdout, syscall.O_RDONLY, 0)
if err != nil {
return nil, err
}
wg.Add(1)
cwg.Add(1)
go func() {
cwg.Done()
p := bufPool.Get().(*[]byte)
defer bufPool.Put(p)
io.CopyBuffer(outw, epollConsole, *p)
epollConsole.Close()
outr.Close()
outw.Close()
wg.Done()
}()
return epollConsole, nil
}
func (p *linuxPlatform) ShutdownConsole(ctx context.Context, cons console.Console) error {
if p.epoller == nil {
return errors.New("uninitialized epoller")
}
epollConsole, ok := cons.(*console.EpollConsole)
if !ok {
return errors.Errorf("expected EpollConsole, got %#v", cons)
}
return epollConsole.Shutdown(p.epoller.CloseConsole)
}
func (p *linuxPlatform) Close() error {
return p.epoller.Close()
}
// initialize a single epoll fd to manage our consoles. `initPlatform` should
// only be called once.
func (s *service) initPlatform() error {
if s.platform != nil {
return nil
}
epoller, err := console.NewEpoller()
if err != nil {
return errors.Wrap(err, "failed to initialize epoller")
}
s.platform = &linuxPlatform{
epoller: epoller,
}
go epoller.Wait()
return nil
}