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moby--moby/container.go
Victor Vieux f9328ad9cc Merge pull request #3201 from jpoimboe/libvirt-prereq-network
Set hostname and IP address from dockerinit
2013-12-13 10:38:17 -08:00

1477 lines
39 KiB
Go

package docker
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"github.com/dotcloud/docker/archive"
"github.com/dotcloud/docker/graphdriver"
"github.com/dotcloud/docker/term"
"github.com/dotcloud/docker/utils"
"github.com/kr/pty"
"io"
"io/ioutil"
"log"
"net"
"os"
"os/exec"
"path"
"strconv"
"strings"
"sync"
"syscall"
"time"
)
var (
ErrNotATTY = errors.New("The PTY is not a file")
ErrNoTTY = errors.New("No PTY found")
)
type Container struct {
sync.Mutex
root string // Path to the "home" of the container, including metadata.
rootfs string // Path to the root filesystem of the container.
ID string
Created time.Time
Path string
Args []string
Config *Config
State State
Image string
network *NetworkInterface
NetworkSettings *NetworkSettings
SysInitPath string
ResolvConfPath string
HostnamePath string
HostsPath string
Name string
Driver string
cmd *exec.Cmd
stdout *utils.WriteBroadcaster
stderr *utils.WriteBroadcaster
stdin io.ReadCloser
stdinPipe io.WriteCloser
ptyMaster io.Closer
runtime *Runtime
waitLock chan struct{}
Volumes map[string]string
// Store rw/ro in a separate structure to preserve reverse-compatibility on-disk.
// Easier than migrating older container configs :)
VolumesRW map[string]bool
hostConfig *HostConfig
activeLinks map[string]*Link
}
// Note: the Config structure should hold only portable information about the container.
// Here, "portable" means "independent from the host we are running on".
// Non-portable information *should* appear in HostConfig.
type Config struct {
Hostname string
Domainname string
User string
Memory int64 // Memory limit (in bytes)
MemorySwap int64 // Total memory usage (memory + swap); set `-1' to disable swap
CpuShares int64 // CPU shares (relative weight vs. other containers)
AttachStdin bool
AttachStdout bool
AttachStderr bool
PortSpecs []string // Deprecated - Can be in the format of 8080/tcp
ExposedPorts map[Port]struct{}
Tty bool // Attach standard streams to a tty, including stdin if it is not closed.
OpenStdin bool // Open stdin
StdinOnce bool // If true, close stdin after the 1 attached client disconnects.
Env []string
Cmd []string
Dns []string
Image string // Name of the image as it was passed by the operator (eg. could be symbolic)
Volumes map[string]struct{}
VolumesFrom string
WorkingDir string
Entrypoint []string
NetworkDisabled bool
}
type HostConfig struct {
Binds []string
ContainerIDFile string
LxcConf []KeyValuePair
Privileged bool
PortBindings map[Port][]PortBinding
Links []string
PublishAllPorts bool
}
type BindMap struct {
SrcPath string
DstPath string
Mode string
}
var (
ErrContainerStart = errors.New("The container failed to start. Unkown error")
ErrContainerStartTimeout = errors.New("The container failed to start due to timed out.")
ErrInvalidWorikingDirectory = errors.New("The working directory is invalid. It needs to be an absolute path.")
ErrConflictAttachDetach = errors.New("Conflicting options: -a and -d")
ErrConflictDetachAutoRemove = errors.New("Conflicting options: -rm and -d")
)
type KeyValuePair struct {
Key string
Value string
}
type PortBinding struct {
HostIp string
HostPort string
}
// 80/tcp
type Port string
func (p Port) Proto() string {
parts := strings.Split(string(p), "/")
if len(parts) == 1 {
return "tcp"
}
return parts[1]
}
func (p Port) Port() string {
return strings.Split(string(p), "/")[0]
}
func (p Port) Int() int {
i, err := parsePort(p.Port())
if err != nil {
panic(err)
}
return i
}
func NewPort(proto, port string) Port {
return Port(fmt.Sprintf("%s/%s", port, proto))
}
type PortMapping map[string]string // Deprecated
type NetworkSettings struct {
IPAddress string
IPPrefixLen int
Gateway string
Bridge string
PortMapping map[string]PortMapping // Deprecated
Ports map[Port][]PortBinding
}
func (settings *NetworkSettings) PortMappingAPI() []APIPort {
var mapping []APIPort
for port, bindings := range settings.Ports {
p, _ := parsePort(port.Port())
if len(bindings) == 0 {
mapping = append(mapping, APIPort{
PublicPort: int64(p),
Type: port.Proto(),
})
continue
}
for _, binding := range bindings {
p, _ := parsePort(port.Port())
h, _ := parsePort(binding.HostPort)
mapping = append(mapping, APIPort{
PrivatePort: int64(p),
PublicPort: int64(h),
Type: port.Proto(),
IP: binding.HostIp,
})
}
}
return mapping
}
// Inject the io.Reader at the given path. Note: do not close the reader
func (container *Container) Inject(file io.Reader, pth string) error {
if err := container.EnsureMounted(); err != nil {
return fmt.Errorf("inject: error mounting container %s: %s", container.ID, err)
}
// Return error if path exists
destPath := path.Join(container.RootfsPath(), pth)
if _, err := os.Stat(destPath); err == nil {
// Since err is nil, the path could be stat'd and it exists
return fmt.Errorf("%s exists", pth)
} else if !os.IsNotExist(err) {
// Expect err might be that the file doesn't exist, so
// if it's some other error, return that.
return err
}
// Make sure the directory exists
if err := os.MkdirAll(path.Join(container.RootfsPath(), path.Dir(pth)), 0755); err != nil {
return err
}
dest, err := os.Create(destPath)
if err != nil {
return err
}
defer dest.Close()
if _, err := io.Copy(dest, file); err != nil {
return err
}
return nil
}
func (container *Container) Cmd() *exec.Cmd {
return container.cmd
}
func (container *Container) When() time.Time {
return container.Created
}
func (container *Container) FromDisk() error {
data, err := ioutil.ReadFile(container.jsonPath())
if err != nil {
return err
}
// Load container settings
// udp broke compat of docker.PortMapping, but it's not used when loading a container, we can skip it
if err := json.Unmarshal(data, container); err != nil && !strings.Contains(err.Error(), "docker.PortMapping") {
return err
}
return container.readHostConfig()
}
func (container *Container) ToDisk() (err error) {
data, err := json.Marshal(container)
if err != nil {
return
}
err = ioutil.WriteFile(container.jsonPath(), data, 0666)
if err != nil {
return
}
return container.writeHostConfig()
}
func (container *Container) readHostConfig() error {
container.hostConfig = &HostConfig{}
// If the hostconfig file does not exist, do not read it.
// (We still have to initialize container.hostConfig,
// but that's OK, since we just did that above.)
_, err := os.Stat(container.hostConfigPath())
if os.IsNotExist(err) {
return nil
}
data, err := ioutil.ReadFile(container.hostConfigPath())
if err != nil {
return err
}
return json.Unmarshal(data, container.hostConfig)
}
func (container *Container) writeHostConfig() (err error) {
data, err := json.Marshal(container.hostConfig)
if err != nil {
return
}
return ioutil.WriteFile(container.hostConfigPath(), data, 0666)
}
func (container *Container) generateEnvConfig(env []string) error {
data, err := json.Marshal(env)
if err != nil {
return err
}
ioutil.WriteFile(container.EnvConfigPath(), data, 0600)
return nil
}
func (container *Container) generateLXCConfig() error {
fo, err := os.Create(container.lxcConfigPath())
if err != nil {
return err
}
defer fo.Close()
return LxcTemplateCompiled.Execute(fo, container)
}
func (container *Container) startPty() error {
ptyMaster, ptySlave, err := pty.Open()
if err != nil {
return err
}
container.ptyMaster = ptyMaster
container.cmd.Stdout = ptySlave
container.cmd.Stderr = ptySlave
// Copy the PTYs to our broadcasters
go func() {
defer container.stdout.CloseWriters()
utils.Debugf("startPty: begin of stdout pipe")
io.Copy(container.stdout, ptyMaster)
utils.Debugf("startPty: end of stdout pipe")
}()
// stdin
if container.Config.OpenStdin {
container.cmd.Stdin = ptySlave
container.cmd.SysProcAttr.Setctty = true
go func() {
defer container.stdin.Close()
utils.Debugf("startPty: begin of stdin pipe")
io.Copy(ptyMaster, container.stdin)
utils.Debugf("startPty: end of stdin pipe")
}()
}
if err := container.cmd.Start(); err != nil {
return err
}
ptySlave.Close()
return nil
}
func (container *Container) start() error {
container.cmd.Stdout = container.stdout
container.cmd.Stderr = container.stderr
if container.Config.OpenStdin {
stdin, err := container.cmd.StdinPipe()
if err != nil {
return err
}
go func() {
defer stdin.Close()
utils.Debugf("start: begin of stdin pipe")
io.Copy(stdin, container.stdin)
utils.Debugf("start: end of stdin pipe")
}()
}
return container.cmd.Start()
}
func (container *Container) Attach(stdin io.ReadCloser, stdinCloser io.Closer, stdout io.Writer, stderr io.Writer) chan error {
var cStdout, cStderr io.ReadCloser
var nJobs int
errors := make(chan error, 3)
if stdin != nil && container.Config.OpenStdin {
nJobs += 1
if cStdin, err := container.StdinPipe(); err != nil {
errors <- err
} else {
go func() {
utils.Debugf("attach: stdin: begin")
defer utils.Debugf("attach: stdin: end")
// No matter what, when stdin is closed (io.Copy unblock), close stdout and stderr
if container.Config.StdinOnce && !container.Config.Tty {
defer cStdin.Close()
} else {
if cStdout != nil {
defer cStdout.Close()
}
if cStderr != nil {
defer cStderr.Close()
}
}
if container.Config.Tty {
_, err = utils.CopyEscapable(cStdin, stdin)
} else {
_, err = io.Copy(cStdin, stdin)
}
if err == io.ErrClosedPipe {
err = nil
}
if err != nil {
utils.Errorf("attach: stdin: %s", err)
}
errors <- err
}()
}
}
if stdout != nil {
nJobs += 1
if p, err := container.StdoutPipe(); err != nil {
errors <- err
} else {
cStdout = p
go func() {
utils.Debugf("attach: stdout: begin")
defer utils.Debugf("attach: stdout: end")
// If we are in StdinOnce mode, then close stdin
if container.Config.StdinOnce && stdin != nil {
defer stdin.Close()
}
if stdinCloser != nil {
defer stdinCloser.Close()
}
_, err := io.Copy(stdout, cStdout)
if err == io.ErrClosedPipe {
err = nil
}
if err != nil {
utils.Errorf("attach: stdout: %s", err)
}
errors <- err
}()
}
} else {
go func() {
if stdinCloser != nil {
defer stdinCloser.Close()
}
if cStdout, err := container.StdoutPipe(); err != nil {
utils.Errorf("attach: stdout pipe: %s", err)
} else {
io.Copy(&utils.NopWriter{}, cStdout)
}
}()
}
if stderr != nil {
nJobs += 1
if p, err := container.StderrPipe(); err != nil {
errors <- err
} else {
cStderr = p
go func() {
utils.Debugf("attach: stderr: begin")
defer utils.Debugf("attach: stderr: end")
// If we are in StdinOnce mode, then close stdin
if container.Config.StdinOnce && stdin != nil {
defer stdin.Close()
}
if stdinCloser != nil {
defer stdinCloser.Close()
}
_, err := io.Copy(stderr, cStderr)
if err == io.ErrClosedPipe {
err = nil
}
if err != nil {
utils.Errorf("attach: stderr: %s", err)
}
errors <- err
}()
}
} else {
go func() {
if stdinCloser != nil {
defer stdinCloser.Close()
}
if cStderr, err := container.StderrPipe(); err != nil {
utils.Errorf("attach: stdout pipe: %s", err)
} else {
io.Copy(&utils.NopWriter{}, cStderr)
}
}()
}
return utils.Go(func() error {
if cStdout != nil {
defer cStdout.Close()
}
if cStderr != nil {
defer cStderr.Close()
}
// FIXME: how to clean up the stdin goroutine without the unwanted side effect
// of closing the passed stdin? Add an intermediary io.Pipe?
for i := 0; i < nJobs; i += 1 {
utils.Debugf("attach: waiting for job %d/%d", i+1, nJobs)
if err := <-errors; err != nil {
utils.Errorf("attach: job %d returned error %s, aborting all jobs", i+1, err)
return err
}
utils.Debugf("attach: job %d completed successfully", i+1)
}
utils.Debugf("attach: all jobs completed successfully")
return nil
})
}
func (container *Container) Start() (err error) {
container.Lock()
defer container.Unlock()
if container.State.IsRunning() {
return fmt.Errorf("The container %s is already running.", container.ID)
}
defer func() {
if err != nil {
container.cleanup()
}
}()
if err := container.EnsureMounted(); err != nil {
return err
}
if container.runtime.networkManager.disabled {
container.Config.NetworkDisabled = true
container.buildHostnameAndHostsFiles("127.0.1.1")
} else {
if err := container.allocateNetwork(); err != nil {
return err
}
container.buildHostnameAndHostsFiles(container.NetworkSettings.IPAddress)
}
// Make sure the config is compatible with the current kernel
if container.Config.Memory > 0 && !container.runtime.capabilities.MemoryLimit {
log.Printf("WARNING: Your kernel does not support memory limit capabilities. Limitation discarded.\n")
container.Config.Memory = 0
}
if container.Config.Memory > 0 && !container.runtime.capabilities.SwapLimit {
log.Printf("WARNING: Your kernel does not support swap limit capabilities. Limitation discarded.\n")
container.Config.MemorySwap = -1
}
if container.runtime.capabilities.IPv4ForwardingDisabled {
log.Printf("WARNING: IPv4 forwarding is disabled. Networking will not work")
}
if container.Volumes == nil || len(container.Volumes) == 0 {
container.Volumes = make(map[string]string)
container.VolumesRW = make(map[string]bool)
}
// Apply volumes from another container if requested
if err := container.applyExternalVolumes(); err != nil {
return err
}
if err := container.createVolumes(); err != nil {
return err
}
if err := container.generateLXCConfig(); err != nil {
return err
}
var lxcStart string = "lxc-start"
if container.hostConfig.Privileged && container.runtime.capabilities.AppArmor {
lxcStart = path.Join(container.runtime.config.Root, "lxc-start-unconfined")
}
params := []string{
lxcStart,
"-n", container.ID,
"-f", container.lxcConfigPath(),
"--",
"/.dockerinit",
}
// Networking
if !container.Config.NetworkDisabled {
network := container.NetworkSettings
params = append(params,
"-g", network.Gateway,
"-i", fmt.Sprintf("%s/%d", network.IPAddress, network.IPPrefixLen),
)
}
// User
if container.Config.User != "" {
params = append(params, "-u", container.Config.User)
}
// Setup environment
env := []string{
"HOME=/",
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"HOSTNAME=" + container.Config.Hostname,
}
if container.Config.Tty {
env = append(env, "TERM=xterm")
}
if container.hostConfig.Privileged {
params = append(params, "-privileged")
}
// Init any links between the parent and children
runtime := container.runtime
children, err := runtime.Children(container.Name)
if err != nil {
return err
}
if len(children) > 0 {
container.activeLinks = make(map[string]*Link, len(children))
// If we encounter an error make sure that we rollback any network
// config and ip table changes
rollback := func() {
for _, link := range container.activeLinks {
link.Disable()
}
container.activeLinks = nil
}
for p, child := range children {
link, err := NewLink(container, child, p, runtime.networkManager.bridgeIface)
if err != nil {
rollback()
return err
}
container.activeLinks[link.Alias()] = link
if err := link.Enable(); err != nil {
rollback()
return err
}
for _, envVar := range link.ToEnv() {
env = append(env, envVar)
}
}
}
for _, elem := range container.Config.Env {
env = append(env, elem)
}
if err := container.generateEnvConfig(env); err != nil {
return err
}
if container.Config.WorkingDir != "" {
workingDir := path.Clean(container.Config.WorkingDir)
utils.Debugf("[working dir] working dir is %s", workingDir)
if err := os.MkdirAll(path.Join(container.RootfsPath(), workingDir), 0755); err != nil {
return nil
}
params = append(params,
"-w", workingDir,
)
}
// Program
params = append(params, "--", container.Path)
params = append(params, container.Args...)
if RootIsShared() {
// lxc-start really needs / to be non-shared, or all kinds of stuff break
// when lxc-start unmount things and those unmounts propagate to the main
// mount namespace.
// What we really want is to clone into a new namespace and then
// mount / MS_REC|MS_SLAVE, but since we can't really clone or fork
// without exec in go we have to do this horrible shell hack...
shellString :=
"mount --make-rslave /; exec " +
utils.ShellQuoteArguments(params)
params = []string{
"unshare", "-m", "--", "/bin/sh", "-c", shellString,
}
}
container.cmd = exec.Command(params[0], params[1:]...)
// Setup logging of stdout and stderr to disk
if err := container.runtime.LogToDisk(container.stdout, container.logPath("json"), "stdout"); err != nil {
return err
}
if err := container.runtime.LogToDisk(container.stderr, container.logPath("json"), "stderr"); err != nil {
return err
}
container.cmd.SysProcAttr = &syscall.SysProcAttr{Setsid: true}
if container.Config.Tty {
err = container.startPty()
} else {
err = container.start()
}
if err != nil {
return err
}
// FIXME: save state on disk *first*, then converge
// this way disk state is used as a journal, eg. we can restore after crash etc.
container.State.SetRunning(container.cmd.Process.Pid)
// Init the lock
container.waitLock = make(chan struct{})
container.ToDisk()
go container.monitor()
defer utils.Debugf("Container running: %v", container.State.IsRunning())
// We wait for the container to be fully running.
// Timeout after 5 seconds. In case of broken pipe, just retry.
// Note: The container can run and finish correctly before
// the end of this loop
for now := time.Now(); time.Since(now) < 5*time.Second; {
// If the container dies while waiting for it, just return
if !container.State.IsRunning() {
return nil
}
output, err := exec.Command("lxc-info", "-s", "-n", container.ID).CombinedOutput()
if err != nil {
utils.Debugf("Error with lxc-info: %s (%s)", err, output)
output, err = exec.Command("lxc-info", "-s", "-n", container.ID).CombinedOutput()
if err != nil {
utils.Debugf("Second Error with lxc-info: %s (%s)", err, output)
return err
}
}
if strings.Contains(string(output), "RUNNING") {
return nil
}
utils.Debugf("Waiting for the container to start (running: %v): %s", container.State.IsRunning(), bytes.TrimSpace(output))
time.Sleep(50 * time.Millisecond)
}
if container.State.IsRunning() {
return ErrContainerStartTimeout
}
return ErrContainerStart
}
func (container *Container) getBindMap() (map[string]BindMap, error) {
// Create the requested bind mounts
binds := make(map[string]BindMap)
// Define illegal container destinations
illegalDsts := []string{"/", "."}
for _, bind := range container.hostConfig.Binds {
// FIXME: factorize bind parsing in parseBind
var src, dst, mode string
arr := strings.Split(bind, ":")
if len(arr) == 2 {
src = arr[0]
dst = arr[1]
mode = "rw"
} else if len(arr) == 3 {
src = arr[0]
dst = arr[1]
mode = arr[2]
} else {
return nil, fmt.Errorf("Invalid bind specification: %s", bind)
}
// Bail if trying to mount to an illegal destination
for _, illegal := range illegalDsts {
if dst == illegal {
return nil, fmt.Errorf("Illegal bind destination: %s", dst)
}
}
bindMap := BindMap{
SrcPath: src,
DstPath: dst,
Mode: mode,
}
binds[path.Clean(dst)] = bindMap
}
return binds, nil
}
func (container *Container) createVolumes() error {
binds, err := container.getBindMap()
if err != nil {
return err
}
volumesDriver := container.runtime.volumes.driver
// Create the requested volumes if they don't exist
for volPath := range container.Config.Volumes {
volPath = path.Clean(volPath)
volIsDir := true
// Skip existing volumes
if _, exists := container.Volumes[volPath]; exists {
continue
}
var srcPath string
var isBindMount bool
srcRW := false
// If an external bind is defined for this volume, use that as a source
if bindMap, exists := binds[volPath]; exists {
isBindMount = true
srcPath = bindMap.SrcPath
if strings.ToLower(bindMap.Mode) == "rw" {
srcRW = true
}
if stat, err := os.Lstat(bindMap.SrcPath); err != nil {
return err
} else {
volIsDir = stat.IsDir()
}
// Otherwise create an directory in $ROOT/volumes/ and use that
} else {
// Do not pass a container as the parameter for the volume creation.
// The graph driver using the container's information ( Image ) to
// create the parent.
c, err := container.runtime.volumes.Create(nil, nil, "", "", nil)
if err != nil {
return err
}
srcPath, err = volumesDriver.Get(c.ID)
if err != nil {
return fmt.Errorf("Driver %s failed to get volume rootfs %s: %s", volumesDriver, c.ID, err)
}
srcRW = true // RW by default
}
container.Volumes[volPath] = srcPath
container.VolumesRW[volPath] = srcRW
// Create the mountpoint
volPath = path.Join(container.RootfsPath(), volPath)
rootVolPath, err := utils.FollowSymlinkInScope(volPath, container.RootfsPath())
if err != nil {
panic(err)
}
if _, err := os.Stat(rootVolPath); err != nil {
if os.IsNotExist(err) {
if volIsDir {
if err := os.MkdirAll(rootVolPath, 0755); err != nil {
return err
}
} else {
if err := os.MkdirAll(path.Dir(rootVolPath), 0755); err != nil {
return err
}
if f, err := os.OpenFile(rootVolPath, os.O_CREATE, 0755); err != nil {
return err
} else {
f.Close()
}
}
}
}
// Do not copy or change permissions if we are mounting from the host
if srcRW && !isBindMount {
volList, err := ioutil.ReadDir(rootVolPath)
if err != nil {
return err
}
if len(volList) > 0 {
srcList, err := ioutil.ReadDir(srcPath)
if err != nil {
return err
}
if len(srcList) == 0 {
// If the source volume is empty copy files from the root into the volume
if err := archive.CopyWithTar(rootVolPath, srcPath); err != nil {
return err
}
var stat syscall.Stat_t
if err := syscall.Stat(rootVolPath, &stat); err != nil {
return err
}
var srcStat syscall.Stat_t
if err := syscall.Stat(srcPath, &srcStat); err != nil {
return err
}
// Change the source volume's ownership if it differs from the root
// files that where just copied
if stat.Uid != srcStat.Uid || stat.Gid != srcStat.Gid {
if err := os.Chown(srcPath, int(stat.Uid), int(stat.Gid)); err != nil {
return err
}
}
}
}
}
}
return nil
}
func (container *Container) applyExternalVolumes() error {
if container.Config.VolumesFrom != "" {
containerSpecs := strings.Split(container.Config.VolumesFrom, ",")
for _, containerSpec := range containerSpecs {
mountRW := true
specParts := strings.SplitN(containerSpec, ":", 2)
switch len(specParts) {
case 0:
return fmt.Errorf("Malformed volumes-from specification: %s", container.Config.VolumesFrom)
case 2:
switch specParts[1] {
case "ro":
mountRW = false
case "rw": // mountRW is already true
default:
return fmt.Errorf("Malformed volumes-from speficication: %s", containerSpec)
}
}
c := container.runtime.Get(specParts[0])
if c == nil {
return fmt.Errorf("Container %s not found. Impossible to mount its volumes", container.ID)
}
for volPath, id := range c.Volumes {
if _, exists := container.Volumes[volPath]; exists {
continue
}
if err := os.MkdirAll(path.Join(container.RootfsPath(), volPath), 0755); err != nil {
return err
}
container.Volumes[volPath] = id
if isRW, exists := c.VolumesRW[volPath]; exists {
container.VolumesRW[volPath] = isRW && mountRW
}
}
}
}
return nil
}
func (container *Container) Run() error {
if err := container.Start(); err != nil {
return err
}
container.Wait()
return nil
}
func (container *Container) Output() (output []byte, err error) {
pipe, err := container.StdoutPipe()
if err != nil {
return nil, err
}
defer pipe.Close()
if err := container.Start(); err != nil {
return nil, err
}
output, err = ioutil.ReadAll(pipe)
container.Wait()
return output, err
}
// Container.StdinPipe returns a WriteCloser which can be used to feed data
// to the standard input of the container's active process.
// Container.StdoutPipe and Container.StderrPipe each return a ReadCloser
// which can be used to retrieve the standard output (and error) generated
// by the container's active process. The output (and error) are actually
// copied and delivered to all StdoutPipe and StderrPipe consumers, using
// a kind of "broadcaster".
func (container *Container) StdinPipe() (io.WriteCloser, error) {
return container.stdinPipe, nil
}
func (container *Container) StdoutPipe() (io.ReadCloser, error) {
reader, writer := io.Pipe()
container.stdout.AddWriter(writer, "")
return utils.NewBufReader(reader), nil
}
func (container *Container) StderrPipe() (io.ReadCloser, error) {
reader, writer := io.Pipe()
container.stderr.AddWriter(writer, "")
return utils.NewBufReader(reader), nil
}
func (container *Container) buildHostnameAndHostsFiles(IP string) {
container.HostnamePath = path.Join(container.root, "hostname")
ioutil.WriteFile(container.HostnamePath, []byte(container.Config.Hostname+"\n"), 0644)
hostsContent := []byte(`
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
`)
container.HostsPath = path.Join(container.root, "hosts")
if container.Config.Domainname != "" {
hostsContent = append([]byte(fmt.Sprintf("%s\t%s.%s %s\n", IP, container.Config.Hostname, container.Config.Domainname, container.Config.Hostname)), hostsContent...)
} else {
hostsContent = append([]byte(fmt.Sprintf("%s\t%s\n", IP, container.Config.Hostname)), hostsContent...)
}
ioutil.WriteFile(container.HostsPath, hostsContent, 0644)
}
func (container *Container) allocateNetwork() error {
if container.Config.NetworkDisabled {
return nil
}
var (
iface *NetworkInterface
err error
)
if container.State.IsGhost() {
if manager := container.runtime.networkManager; manager.disabled {
iface = &NetworkInterface{disabled: true}
} else {
iface = &NetworkInterface{
IPNet: net.IPNet{IP: net.ParseIP(container.NetworkSettings.IPAddress), Mask: manager.bridgeNetwork.Mask},
Gateway: manager.bridgeNetwork.IP,
manager: manager,
}
if iface != nil && iface.IPNet.IP != nil {
ipNum := ipToInt(iface.IPNet.IP)
manager.ipAllocator.inUse[ipNum] = struct{}{}
} else {
iface, err = container.runtime.networkManager.Allocate()
if err != nil {
return err
}
}
}
} else {
iface, err = container.runtime.networkManager.Allocate()
if err != nil {
return err
}
}
if container.Config.PortSpecs != nil {
utils.Debugf("Migrating port mappings for container: %s", strings.Join(container.Config.PortSpecs, ", "))
if err := migratePortMappings(container.Config, container.hostConfig); err != nil {
return err
}
container.Config.PortSpecs = nil
if err := container.writeHostConfig(); err != nil {
return err
}
}
var (
portSpecs = make(map[Port]struct{})
bindings = make(map[Port][]PortBinding)
)
if !container.State.IsGhost() {
if container.Config.ExposedPorts != nil {
portSpecs = container.Config.ExposedPorts
}
if container.hostConfig.PortBindings != nil {
bindings = container.hostConfig.PortBindings
}
} else {
if container.NetworkSettings.Ports != nil {
for port, binding := range container.NetworkSettings.Ports {
portSpecs[port] = struct{}{}
bindings[port] = binding
}
}
}
container.NetworkSettings.PortMapping = nil
for port := range portSpecs {
binding := bindings[port]
if container.hostConfig.PublishAllPorts && len(binding) == 0 {
binding = append(binding, PortBinding{})
}
for i := 0; i < len(binding); i++ {
b := binding[i]
nat, err := iface.AllocatePort(port, b)
if err != nil {
iface.Release()
return err
}
utils.Debugf("Allocate port: %s:%s->%s", nat.Binding.HostIp, port, nat.Binding.HostPort)
binding[i] = nat.Binding
}
bindings[port] = binding
}
container.writeHostConfig()
container.NetworkSettings.Ports = bindings
container.network = iface
container.NetworkSettings.Bridge = container.runtime.networkManager.bridgeIface
container.NetworkSettings.IPAddress = iface.IPNet.IP.String()
container.NetworkSettings.IPPrefixLen, _ = iface.IPNet.Mask.Size()
container.NetworkSettings.Gateway = iface.Gateway.String()
return nil
}
func (container *Container) releaseNetwork() {
if container.Config.NetworkDisabled || container.network == nil {
return
}
container.network.Release()
container.network = nil
container.NetworkSettings = &NetworkSettings{}
}
// FIXME: replace this with a control socket within dockerinit
func (container *Container) waitLxc() error {
for {
output, err := exec.Command("lxc-info", "-n", container.ID).CombinedOutput()
if err != nil {
return err
}
if !strings.Contains(string(output), "RUNNING") {
return nil
}
time.Sleep(500 * time.Millisecond)
}
}
func (container *Container) monitor() {
// Wait for the program to exit
// If the command does not exist, try to wait via lxc
// (This probably happens only for ghost containers, i.e. containers that were running when Docker started)
if container.cmd == nil {
utils.Debugf("monitor: waiting for container %s using waitLxc", container.ID)
if err := container.waitLxc(); err != nil {
utils.Errorf("monitor: while waiting for container %s, waitLxc had a problem: %s", container.ID, err)
}
} else {
utils.Debugf("monitor: waiting for container %s using cmd.Wait", container.ID)
if err := container.cmd.Wait(); err != nil {
// Since non-zero exit status and signal terminations will cause err to be non-nil,
// we have to actually discard it. Still, log it anyway, just in case.
utils.Debugf("monitor: cmd.Wait reported exit status %s for container %s", err, container.ID)
}
}
utils.Debugf("monitor: container %s finished", container.ID)
exitCode := -1
if container.cmd != nil {
exitCode = container.cmd.ProcessState.Sys().(syscall.WaitStatus).ExitStatus()
}
if container.runtime != nil && container.runtime.srv != nil {
container.runtime.srv.LogEvent("die", container.ID, container.runtime.repositories.ImageName(container.Image))
}
// Cleanup
container.cleanup()
// Re-create a brand new stdin pipe once the container exited
if container.Config.OpenStdin {
container.stdin, container.stdinPipe = io.Pipe()
}
// Report status back
container.State.SetStopped(exitCode)
// Release the lock
close(container.waitLock)
if err := container.ToDisk(); err != nil {
// FIXME: there is a race condition here which causes this to fail during the unit tests.
// If another goroutine was waiting for Wait() to return before removing the container's root
// from the filesystem... At this point it may already have done so.
// This is because State.setStopped() has already been called, and has caused Wait()
// to return.
// FIXME: why are we serializing running state to disk in the first place?
//log.Printf("%s: Failed to dump configuration to the disk: %s", container.ID, err)
}
}
func (container *Container) cleanup() {
container.releaseNetwork()
// Disable all active links
if container.activeLinks != nil {
for _, link := range container.activeLinks {
link.Disable()
}
}
if container.Config.OpenStdin {
if err := container.stdin.Close(); err != nil {
utils.Errorf("%s: Error close stdin: %s", container.ID, err)
}
}
if err := container.stdout.CloseWriters(); err != nil {
utils.Errorf("%s: Error close stdout: %s", container.ID, err)
}
if err := container.stderr.CloseWriters(); err != nil {
utils.Errorf("%s: Error close stderr: %s", container.ID, err)
}
if container.ptyMaster != nil {
if err := container.ptyMaster.Close(); err != nil {
utils.Errorf("%s: Error closing Pty master: %s", container.ID, err)
}
}
if err := container.Unmount(); err != nil {
log.Printf("%v: Failed to umount filesystem: %v", container.ID, err)
}
}
func (container *Container) kill(sig int) error {
container.Lock()
defer container.Unlock()
if !container.State.IsRunning() {
return nil
}
if output, err := exec.Command("lxc-kill", "-n", container.ID, strconv.Itoa(sig)).CombinedOutput(); err != nil {
log.Printf("error killing container %s (%s, %s)", utils.TruncateID(container.ID), output, err)
return err
}
return nil
}
func (container *Container) Kill() error {
if !container.State.IsRunning() {
return nil
}
// 1. Send SIGKILL
if err := container.kill(9); err != nil {
return err
}
// 2. Wait for the process to die, in last resort, try to kill the process directly
if err := container.WaitTimeout(10 * time.Second); err != nil {
if container.cmd == nil {
return fmt.Errorf("lxc-kill failed, impossible to kill the container %s", utils.TruncateID(container.ID))
}
log.Printf("Container %s failed to exit within 10 seconds of lxc-kill %s - trying direct SIGKILL", "SIGKILL", utils.TruncateID(container.ID))
if err := container.cmd.Process.Kill(); err != nil {
return err
}
}
container.Wait()
return nil
}
func (container *Container) Stop(seconds int) error {
if !container.State.IsRunning() {
return nil
}
// 1. Send a SIGTERM
if err := container.kill(15); err != nil {
utils.Debugf("Error sending kill SIGTERM: %s", err)
log.Print("Failed to send SIGTERM to the process, force killing")
if err := container.kill(9); err != nil {
return err
}
}
// 2. Wait for the process to exit on its own
if err := container.WaitTimeout(time.Duration(seconds) * time.Second); err != nil {
log.Printf("Container %v failed to exit within %d seconds of SIGTERM - using the force", container.ID, seconds)
// 3. If it doesn't, then send SIGKILL
if err := container.Kill(); err != nil {
return err
}
}
return nil
}
func (container *Container) Restart(seconds int) error {
if err := container.Stop(seconds); err != nil {
return err
}
return container.Start()
}
// Wait blocks until the container stops running, then returns its exit code.
func (container *Container) Wait() int {
<-container.waitLock
return container.State.GetExitCode()
}
func (container *Container) Resize(h, w int) error {
pty, ok := container.ptyMaster.(*os.File)
if !ok {
return fmt.Errorf("ptyMaster does not have Fd() method")
}
return term.SetWinsize(pty.Fd(), &term.Winsize{Height: uint16(h), Width: uint16(w)})
}
func (container *Container) ExportRw() (archive.Archive, error) {
if err := container.EnsureMounted(); err != nil {
return nil, err
}
if container.runtime == nil {
return nil, fmt.Errorf("Can't load storage driver for unregistered container %s", container.ID)
}
return container.runtime.Diff(container)
}
func (container *Container) Export() (archive.Archive, error) {
if err := container.EnsureMounted(); err != nil {
return nil, err
}
return archive.Tar(container.RootfsPath(), archive.Uncompressed)
}
func (container *Container) WaitTimeout(timeout time.Duration) error {
done := make(chan bool)
go func() {
container.Wait()
done <- true
}()
select {
case <-time.After(timeout):
return fmt.Errorf("Timed Out")
case <-done:
return nil
}
}
func (container *Container) EnsureMounted() error {
// FIXME: EnsureMounted is deprecated because drivers are now responsible
// for re-entrant mounting in their Get() method.
return container.Mount()
}
func (container *Container) Mount() error {
return container.runtime.Mount(container)
}
func (container *Container) Changes() ([]archive.Change, error) {
return container.runtime.Changes(container)
}
func (container *Container) GetImage() (*Image, error) {
if container.runtime == nil {
return nil, fmt.Errorf("Can't get image of unregistered container")
}
return container.runtime.graph.Get(container.Image)
}
func (container *Container) Unmount() error {
return container.runtime.Unmount(container)
}
func (container *Container) logPath(name string) string {
return path.Join(container.root, fmt.Sprintf("%s-%s.log", container.ID, name))
}
func (container *Container) ReadLog(name string) (io.Reader, error) {
return os.Open(container.logPath(name))
}
func (container *Container) hostConfigPath() string {
return path.Join(container.root, "hostconfig.json")
}
func (container *Container) jsonPath() string {
return path.Join(container.root, "config.json")
}
func (container *Container) EnvConfigPath() string {
return path.Join(container.root, "config.env")
}
func (container *Container) lxcConfigPath() string {
return path.Join(container.root, "config.lxc")
}
// This method must be exported to be used from the lxc template
func (container *Container) RootfsPath() string {
return container.rootfs
}
func validateID(id string) error {
if id == "" {
return fmt.Errorf("Invalid empty id")
}
return nil
}
// GetSize, return real size, virtual size
func (container *Container) GetSize() (int64, int64) {
var (
sizeRw, sizeRootfs int64
err error
driver = container.runtime.driver
)
if err := container.EnsureMounted(); err != nil {
utils.Errorf("Warning: failed to compute size of container rootfs %s: %s", container.ID, err)
return sizeRw, sizeRootfs
}
if differ, ok := container.runtime.driver.(graphdriver.Differ); ok {
sizeRw, err = differ.DiffSize(container.ID)
if err != nil {
utils.Errorf("Warning: driver %s couldn't return diff size of container %s: %s", driver, container.ID, err)
// FIXME: GetSize should return an error. Not changing it now in case
// there is a side-effect.
sizeRw = -1
}
} else {
changes, _ := container.Changes()
if changes != nil {
sizeRw = archive.ChangesSize(container.RootfsPath(), changes)
} else {
sizeRw = -1
}
}
if _, err = os.Stat(container.RootfsPath()); err != nil {
if sizeRootfs, err = utils.TreeSize(container.RootfsPath()); err != nil {
sizeRootfs = -1
}
}
return sizeRw, sizeRootfs
}
func (container *Container) Copy(resource string) (archive.Archive, error) {
if err := container.EnsureMounted(); err != nil {
return nil, err
}
var filter []string
basePath := path.Join(container.RootfsPath(), resource)
stat, err := os.Stat(basePath)
if err != nil {
return nil, err
}
if !stat.IsDir() {
d, f := path.Split(basePath)
basePath = d
filter = []string{f}
} else {
filter = []string{path.Base(basePath)}
basePath = path.Dir(basePath)
}
return archive.TarFilter(basePath, &archive.TarOptions{
Compression: archive.Uncompressed,
Includes: filter,
Recursive: true,
})
}
// Returns true if the container exposes a certain port
func (container *Container) Exposes(p Port) bool {
_, exists := container.Config.ExposedPorts[p]
return exists
}
func (container *Container) GetPtyMaster() (*os.File, error) {
if container.ptyMaster == nil {
return nil, ErrNoTTY
}
if pty, ok := container.ptyMaster.(*os.File); ok {
return pty, nil
}
return nil, ErrNotATTY
}