cri-o/oci/container.go
Alexander Larsson 7bb957bf75 Implement non-terminal attach
We use a SOCK_SEQPACKET socket for the attach unix domain socket, which
means the kernel will ensure that the reading side only ever get the
data from one write operation. We use this for frameing, where the
first byte is the pipe that the next bytes are for. We have to make sure
that all reads from the socket are using at least the same size of buffer
as the write side, because otherwise the extra data in the message
will be dropped.

This also adds a stdin pipe for the container, similar to the ones we
use for stdout/err, because we need a way for an attached client
to write to stdin, even if not using a tty.

This fixes https://github.com/kubernetes-incubator/cri-o/issues/569

Signed-off-by: Alexander Larsson <alexl@redhat.com>
2017-06-14 22:59:50 +02:00

176 lines
4.4 KiB
Go

package oci
import (
"encoding/json"
"fmt"
"os"
"path/filepath"
"strings"
"sync"
"time"
"github.com/containernetworking/cni/pkg/ns"
"github.com/docker/docker/pkg/signal"
specs "github.com/opencontainers/runtime-spec/specs-go"
"k8s.io/apimachinery/pkg/fields"
pb "k8s.io/kubernetes/pkg/kubelet/api/v1alpha1/runtime"
)
const (
defaultStopSignal = "TERM"
)
// Container represents a runtime container.
type Container struct {
id string
name string
logPath string
labels fields.Set
annotations fields.Set
image *pb.ImageSpec
sandbox string
netns ns.NetNS
terminal bool
stdin bool
stdinOnce bool
privileged bool
state *ContainerState
metadata *pb.ContainerMetadata
opLock sync.Mutex
// this is the /var/run/storage/... directory, erased on reboot
bundlePath string
// this is the /var/lib/storage/... directory
dir string
stopSignal string
}
// ContainerState represents the status of a container.
type ContainerState struct {
specs.State
Created time.Time `json:"created"`
Started time.Time `json:"started,omitempty"`
Finished time.Time `json:"finished,omitempty"`
ExitCode int32 `json:"exitCode,omitempty"`
OOMKilled bool `json:"oomKilled,omitempty"`
Error string `json:"error,omitempty"`
}
// NewContainer creates a container object.
func NewContainer(id string, name string, bundlePath string, logPath string, netns ns.NetNS, labels map[string]string, annotations map[string]string, image *pb.ImageSpec, metadata *pb.ContainerMetadata, sandbox string, terminal bool, stdin bool, stdinOnce bool, privileged bool, dir string, created time.Time, stopSignal string) (*Container, error) {
state := &ContainerState{}
state.Created = created
c := &Container{
id: id,
name: name,
bundlePath: bundlePath,
logPath: logPath,
labels: labels,
sandbox: sandbox,
netns: netns,
terminal: terminal,
stdin: stdin,
stdinOnce: stdinOnce,
privileged: privileged,
metadata: metadata,
annotations: annotations,
image: image,
dir: dir,
state: state,
stopSignal: stopSignal,
}
return c, nil
}
// GetStopSignal returns the container's own stop signal configured from the
// image configuration or the default one.
func (c *Container) GetStopSignal() string {
if c.stopSignal == "" {
return defaultStopSignal
}
cleanSignal := strings.TrimPrefix(strings.ToUpper(c.stopSignal), "SIG")
_, ok := signal.SignalMap[cleanSignal]
if !ok {
return defaultStopSignal
}
return cleanSignal
}
// FromDisk restores container's state from disk
func (c *Container) FromDisk() error {
jsonSource, err := os.Open(c.StatePath())
if err != nil {
return err
}
defer jsonSource.Close()
dec := json.NewDecoder(jsonSource)
return dec.Decode(c.state)
}
// StatePath returns the containers state.json path
func (c *Container) StatePath() string {
return filepath.Join(c.dir, "state.json")
}
// CreatedAt returns the container creation time
func (c *Container) CreatedAt() time.Time {
return c.state.Created
}
// Name returns the name of the container.
func (c *Container) Name() string {
return c.name
}
// ID returns the id of the container.
func (c *Container) ID() string {
return c.id
}
// BundlePath returns the bundlePath of the container.
func (c *Container) BundlePath() string {
return c.bundlePath
}
// LogPath returns the log path of the container.
func (c *Container) LogPath() string {
return c.logPath
}
// Labels returns the labels of the container.
func (c *Container) Labels() map[string]string {
return c.labels
}
// Annotations returns the annotations of the container.
func (c *Container) Annotations() map[string]string {
return c.annotations
}
// Image returns the image of the container.
func (c *Container) Image() *pb.ImageSpec {
return c.image
}
// Sandbox returns the sandbox name of the container.
func (c *Container) Sandbox() string {
return c.sandbox
}
// NetNsPath returns the path to the network namespace of the container.
func (c *Container) NetNsPath() (string, error) {
if c.state == nil {
return "", fmt.Errorf("container state is not populated")
}
if c.netns == nil {
return fmt.Sprintf("/proc/%d/ns/net", c.state.Pid), nil
}
return c.netns.Path(), nil
}
// Metadata returns the metadata of the container.
func (c *Container) Metadata() *pb.ContainerMetadata {
return c.metadata
}