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.Stat(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
}
if p, err := filepath.EvalSymlinks(srcPath); err != nil {
return err
} else {
srcPath = p
}
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 {
return 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 were 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) 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.Mount(); 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.sysInfo.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.sysInfo.SwapLimit {
log.Printf("WARNING: Your kernel does not support swap limit capabilities. Limitation discarded.\n")
container.Config.MemorySwap = -1
}
if container.runtime.sysInfo.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
}
// 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")
}
// 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
}
root := container.RootfsPath()
if container.Config.WorkingDir != "" {
container.Config.WorkingDir = path.Clean(container.Config.WorkingDir)
if err := os.MkdirAll(path.Join(root, container.Config.WorkingDir), 0755); err != nil {
return nil
}
}
envPath, err := container.EnvConfigPath()
if err != nil {
return err
}
// Mount docker specific files into the containers root fs
if err := mount.Mount(runtime.sysInitPath, path.Join(root, "/.dockerinit"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(envPath, path.Join(root, "/.dockerenv"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(container.ResolvConfPath, path.Join(root, "/etc/resolv.conf"), "none", "bind,ro"); err != nil {
return err
}
if container.HostnamePath != "" && container.HostsPath != "" {
if err := mount.Mount(container.HostnamePath, path.Join(root, "/etc/hostname"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(container.HostsPath, path.Join(root, "/etc/hosts"), "none", "bind,ro"); err != nil {
return err
}
}
// Mount user specified volumes
for r, v := range container.Volumes {
mountAs := "ro"
if container.VolumesRW[r] {
mountAs = "rw"
}
r = path.Join(root, r)
if p, err := utils.FollowSymlinkInScope(r, root); err != nil {
return err
} else {
r = p
}
if err := mount.Mount(v, r, "none", fmt.Sprintf("bind,%s", mountAs)); err != nil {
return err
}
}
populateCommand(container)
// 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.waitLock = make(chan struct{})
// Setuping pipes and/or Pty
var setup func() error
if container.Config.Tty {
setup = container.setupPty
} else {
setup = container.setupStd
}
if err := setup(); err != nil {
return err
}
callbackLock := make(chan struct{})
callback := func(command *execdriver.Command) {
container.State.SetRunning(command.Pid())
if command.Tty {
// The callback is called after the process Start()
// so we are in the parent process. In TTY mode, stdin/out/err is the PtySlace
// which we close here.
if c, ok := command.Stdout.(io.Closer); ok {
c.Close()
}
}
if err := container.ToDisk(); err != nil {
utils.Debugf("%s", err)
}
close(callbackLock)
}
// We use a callback here instead of a goroutine and an chan for
// syncronization purposes
cErr := utils.Go(func() error { return container.monitor(callback) })
// Start should not return until the process is actually running
select {
case <-callbackLock:
case err := <-cErr:
return err
}
return nil
}
func mountVolumesForContainer(container *Container, envPath string) error {
// Setup the root fs as a bind mount of the base fs
var (
root = container.RootfsPath()
runtime = container.runtime
)
if err := os.MkdirAll(root, 0755); err != nil && !os.IsExist(err) {
return nil
}
// Create a bind mount of the base fs as a place where we can add mounts
// without affecting the ability to access the base fs
if err := mount.Mount(container.basefs, root, "none", "bind,rw"); err != nil {
return err
}
// Make sure the root fs is private so the mounts here don't propagate to basefs
if err := mount.ForceMount(root, root, "none", "private"); err != nil {
return err
}
// Mount docker specific files into the containers root fs
if err := mount.Mount(runtime.sysInitPath, filepath.Join(root, "/.dockerinit"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(envPath, filepath.Join(root, "/.dockerenv"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(container.ResolvConfPath, filepath.Join(root, "/etc/resolv.conf"), "none", "bind,ro"); err != nil {
return err
}
if container.HostnamePath != "" && container.HostsPath != "" {
if err := mount.Mount(container.HostnamePath, filepath.Join(root, "/etc/hostname"), "none", "bind,ro"); err != nil {
return err
}
if err := mount.Mount(container.HostsPath, filepath.Join(root, "/etc/hosts"), "none", "bind,ro"); err != nil {
return err
}
}
// Mount user specified volumes
for r, v := range container.Volumes {
mountAs := "ro"
if container.VolumesRW[r] {
mountAs = "rw"
}
r = filepath.Join(root, r)
if p, err := utils.FollowSymlinkInScope(r, root); err != nil {
return err
} else {
r = p
}
if err := mount.Mount(v, r, "none", fmt.Sprintf("bind,%s", mountAs)); err != nil {
return err
}
}
return nil
}
func (b *buildFile) addContext(container *runtime.Container, orig, dest string, remote bool) error {
var (
err error
origPath = path.Join(b.contextPath, orig)
destPath = path.Join(container.RootfsPath(), dest)
)
if destPath != container.RootfsPath() {
destPath, err = utils.FollowSymlinkInScope(destPath, container.RootfsPath())
if err != nil {
return err
}
}
// Preserve the trailing '/'
if strings.HasSuffix(dest, "/") {
destPath = destPath + "/"
}
fi, err := os.Stat(origPath)
if err != nil {
if os.IsNotExist(err) {
return fmt.Errorf("%s: no such file or directory", orig)
}
return err
}
chownR := func(destPath string, uid, gid int) error {
return filepath.Walk(destPath, func(path string, info os.FileInfo, err error) error {
if err := os.Lchown(path, uid, gid); err != nil {
return err
}
return nil
})
}
if fi.IsDir() {
if err := archive.CopyWithTar(origPath, destPath); err != nil {
return err
}
if err := chownR(destPath, 0, 0); err != nil {
return err
}
return nil
}
// First try to unpack the source as an archive
// to support the untar feature we need to clean up the path a little bit
// because tar is very forgiving. First we need to strip off the archive's
// filename from the path but this is only added if it does not end in / .
tarDest := destPath
if strings.HasSuffix(tarDest, "/") {
tarDest = filepath.Dir(destPath)
}
// If we are adding a remote file, do not try to untar it
if !remote {
// try to successfully untar the orig
if err := archive.UntarPath(origPath, tarDest); err == nil {
return nil
}
utils.Debugf("Couldn't untar %s to %s: %s", origPath, destPath, err)
}
// If that fails, just copy it as a regular file
// but do not use all the magic path handling for the tar path
if err := os.MkdirAll(path.Dir(destPath), 0755); err != nil {
return err
}
if err := archive.CopyWithTar(origPath, destPath); err != nil {
return err
}
if err := chownR(destPath, 0, 0); err != nil {
return err
}
return nil
}
func createVolumes(container *Container) error {
binds, err := getBindMap(container)
if err != nil {
return err
}
volumesDriver := container.daemon.volumes.Driver()
// Create the requested volumes if they don't exist
for volPath := range container.Config.Volumes {
volPath = filepath.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 !filepath.IsAbs(srcPath) {
return fmt.Errorf("%s must be an absolute path", srcPath)
}
if strings.ToLower(bindMap.Mode) == "rw" {
srcRW = true
}
if stat, err := os.Stat(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.daemon.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
}
if p, err := filepath.EvalSymlinks(srcPath); err != nil {
return err
} else {
srcPath = p
}
// Create the mountpoint
rootVolPath, err := utils.FollowSymlinkInScope(filepath.Join(container.basefs, volPath), container.basefs)
if err != nil {
return err
}
newVolPath, err := filepath.Rel(container.basefs, rootVolPath)
if err != nil {
return err
}
newVolPath = "/" + newVolPath
if volPath != newVolPath {
delete(container.Volumes, volPath)
delete(container.VolumesRW, volPath)
}
container.Volumes[newVolPath] = srcPath
container.VolumesRW[newVolPath] = srcRW
if err := createIfNotExists(rootVolPath, volIsDir); err != nil {
return err
}
// 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 were 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
}
