func (d *driver) generateEnvConfig(c *execdriver.Command) error {
data, err := json.Marshal(c.Env)
if err != nil {
return err
}
p := path.Join(d.root, "containers", c.ID, "config.env")
c.Mounts = append(c.Mounts, execdriver.Mount{p, "/.dockerenv", false, true})
return ioutil.WriteFile(p, data, 0600)
}
func (d *driver) Run(c *execdriver.Command, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (int, error) {
var (
term execdriver.Terminal
err error
)
if c.Tty {
term, err = NewTtyConsole(c, pipes)
} else {
term, err = execdriver.NewStdConsole(c, pipes)
}
c.Terminal = term
c.Mounts = append(c.Mounts, execdriver.Mount{d.initPath, c.InitPath, false, true})
if err := d.generateEnvConfig(c); err != nil {
return -1, err
}
configPath, err := d.generateLXCConfig(c)
if err != nil {
return -1, err
}
params := []string{
"lxc-start",
"-n", c.ID,
"-f", configPath,
"--",
c.InitPath,
"-driver",
DriverName,
}
if c.Network.Interface != nil {
params = append(params,
"-g", c.Network.Interface.Gateway,
"-i", fmt.Sprintf("%s/%d", c.Network.Interface.IPAddress, c.Network.Interface.IPPrefixLen),
)
}
params = append(params,
"-mtu", strconv.Itoa(c.Network.Mtu),
)
if c.User != "" {
params = append(params, "-u", c.User)
}
if c.Privileged {
if d.apparmor {
params[0] = path.Join(d.root, "lxc-start-unconfined")
}
params = append(params, "-privileged")
}
if c.WorkingDir != "" {
params = append(params, "-w", c.WorkingDir)
}
if len(c.CapAdd) > 0 {
params = append(params, "-cap-add", strings.Join(c.CapAdd, " "))
}
if len(c.CapDrop) > 0 {
params = append(params, "-cap-drop", strings.Join(c.CapDrop, " "))
}
params = append(params, "--", c.Entrypoint)
params = append(params, c.Arguments...)
if d.sharedRoot {
// 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,
}
}
var (
name = params[0]
arg = params[1:]
)
aname, err := exec.LookPath(name)
if err != nil {
aname = name
}
c.Path = aname
c.Args = append([]string{name}, arg...)
if err := nodes.CreateDeviceNodes(c.Rootfs, c.AutoCreatedDevices); err != nil {
return -1, err
}
if err := c.Start(); err != nil {
return -1, err
}
var (
waitErr error
waitLock = make(chan struct{})
)
go func() {
if err := c.Wait(); err != nil {
if _, ok := err.(*exec.ExitError); !ok { // Do not propagate the error if it's simply a status code != 0
waitErr = err
}
}
close(waitLock)
}()
// Poll lxc for RUNNING status
pid, err := d.waitForStart(c, waitLock)
if err != nil {
if c.Process != nil {
c.Process.Kill()
c.Wait()
}
return -1, err
}
c.ContainerPid = pid
if startCallback != nil {
startCallback(c)
}
<-waitLock
return getExitCode(c), waitErr
}