Move environment configuration to Process

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

configs/config.go

@@ -55,11 +55,6 @@ type Config struct {
 	// WorkingDir will change the processes current working directory inside the container's rootfs
 	WorkingDir string `json:"working_dir,omitempty"`
 
-	// Env will populate the processes environment with the provided values
-	// Any values from the parent processes will be cleared before the values
-	// provided in Env are provided to the process
-	Env []string `json:"environment,omitempty"`
-
 	// Console is the path to the console allocated to the container.
 	Console string `json:"console,omitempty"`
 

integration/exec_test.go

@@ -261,6 +261,7 @@ func TestEnter(t *testing.T) {
 
 	pconfig := libcontainer.Process{
 		Args:   []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"},
+		Env:    standardEnvironment,
 		Stdin:  stdinR,
 		Stdout: &stdout,
 	}
@@ -361,6 +362,7 @@ func TestFreeze(t *testing.T) {
 
 	pconfig := libcontainer.Process{
 		Args:  []string{"cat"},
+		Env:   standardEnvironment,
 		Stdin: stdinR,
 	}
 	pid, err := container.Start(&pconfig)

integration/template_test.go

@@ -6,6 +6,13 @@ import (
 	"github.com/docker/libcontainer/configs"
 )
 
+var standardEnvironment = []string{
+	"HOME=/root",
+	"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
+	"HOSTNAME=integration",
+	"TERM=xterm",
+}
+
 // newTemplateConfig returns a base template for running a container
 //
 // it uses a network strategy of just setting a loopback interface
@@ -45,12 +52,6 @@ func newTemplateConfig(rootfs string) *configs.Config {
 
 		Devices:  configs.DefaultAutoCreatedDevices,
 		Hostname: "integration",
-		Env: []string{
-			"HOME=/root",
-			"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
-			"HOSTNAME=integration",
-			"TERM=xterm",
-		},
 		Networks: []*configs.Network{
 			{
 				Type:    "loopback",

integration/utils_test.go

@@ -93,6 +93,7 @@ func runContainer(config *configs.Config, console string, args ...string) (buffe
 
 	process := &libcontainer.Process{
 		Args:   args,
+		Env:    standardEnvironment,
 		Stdin:  buffers.Stdin,
 		Stdout: buffers.Stdout,
 		Stderr: buffers.Stderr,

linux_container.go

@@ -18,10 +18,6 @@ import (
 	"github.com/golang/glog"
 )
 
-const (
-	EXIT_SIGNAL_OFFSET = 128
-)
-
 type pid struct {
 	Pid int `json:"Pid"`
 }
@@ -50,8 +46,7 @@ func (c *linuxContainer) Status() (configs.Status, error) {
 		return configs.Destroyed, nil
 	}
 	// return Running if the init process is alive
-	err := syscall.Kill(c.state.InitPid, 0)
+	if err := syscall.Kill(c.state.InitPid, 0); err != nil {
-	if err != nil {
 		if err == syscall.ESRCH {
 			return configs.Destroyed, nil
 		}
@@ -96,10 +91,9 @@ func (c *linuxContainer) Start(process *Process) (int, error) {
 	cmd := c.commandTemplate(process)
 	if status != configs.Destroyed {
 		// TODO: (crosbymichael) check out console use for execin
-		return c.startNewProcess(cmd, process.Args)
+		return c.startNewProcess(cmd, process)
-		//return namespaces.ExecIn(process.Args, c.config.Env, "", cmd, c.config, c.state)
 	}
-	if err := c.startInitialProcess(cmd, process.Args); err != nil {
+	if err := c.startInitialProcess(cmd, process); err != nil {
 		return -1, err
 	}
 	return c.state.InitPid, nil
@@ -112,7 +106,7 @@ func (c *linuxContainer) commandTemplate(process *Process) *exec.Cmd {
 	cmd.Stdin = process.Stdin
 	cmd.Stdout = process.Stdout
 	cmd.Stderr = process.Stderr
-	cmd.Env = c.config.Env
+	cmd.Env = process.Env
 	cmd.Dir = c.config.Rootfs
 	if cmd.SysProcAttr == nil {
 		cmd.SysProcAttr = &syscall.SysProcAttr{}
@@ -122,9 +116,9 @@ func (c *linuxContainer) commandTemplate(process *Process) *exec.Cmd {
 }
 
 // startNewProcess adds another process to an already running container
-func (c *linuxContainer) startNewProcess(cmd *exec.Cmd, args []string) (int, error) {
+func (c *linuxContainer) startNewProcess(cmd *exec.Cmd, process *Process) (int, error) {
 	glog.Info("start new container process")
-	parent, child, err := newInitPipe()
+	parent, child, err := c.newInitPipe()
 	if err != nil {
 		return -1, err
 	}
@@ -169,18 +163,20 @@ func (c *linuxContainer) startNewProcess(cmd *exec.Cmd, args []string) (int, err
 	}
 	if err := json.NewEncoder(parent).Encode(&initConfig{
 		Config: c.config,
-		Args:   args,
+		Args:   process.Args,
+		Env:    process.Env,
 	}); err != nil {
 		return terminate(err)
 	}
 	return pid.Pid, nil
 }
 
-func (c *linuxContainer) startInitialProcess(cmd *exec.Cmd, args []string) error {
+// startInitialProcess starts PID 1 for the container.
+func (c *linuxContainer) startInitialProcess(cmd *exec.Cmd, process *Process) error {
 	glog.Info("starting container initial process")
 	// create a pipe so that we can syncronize with the namespaced process and
 	// pass the state and configuration to the child process
-	parent, child, err := newInitPipe()
+	parent, child, err := c.newInitPipe()
 	if err != nil {
 		return err
 	}
@@ -239,13 +235,14 @@ func (c *linuxContainer) startInitialProcess(cmd *exec.Cmd, args []string) error
 		return terminate(err)
 	}
 	iconfig := &initConfig{
-		Args:         args,
+		Args:         process.Args,
 		Config:       c.config,
+		Env:          process.Env,
 		NetworkState: &networkState,
 	}
 	// Start the setup process to setup the init process
 	if c.config.Namespaces.Contains(configs.NEWUSER) {
-		if err = executeSetupCmd(cmd.Args, cmd.Process.Pid, c.config, iconfig, &networkState); err != nil {
+		if err = c.executeSetupCmd(cmd.Args, cmd.Process.Pid, c.config, iconfig, &networkState); err != nil {
 			return terminate(err)
 		}
 	}
@@ -281,6 +278,7 @@ func (c *linuxContainer) Destroy() error {
 	if status != configs.Destroyed {
 		return newGenericError(nil, ContainerNotStopped)
 	}
+	// TODO: remove cgroups
 	return os.RemoveAll(c.root)
 }
 
@@ -297,6 +295,7 @@ func (c *linuxContainer) Signal(signal os.Signal) error {
 	panic("not implemented")
 }
 
+// TODO: rename to be more descriptive
 func (c *linuxContainer) OOM() (<-chan struct{}, error) {
 	return NotifyOnOOM(c.state)
 }
@@ -322,7 +321,7 @@ func (c *linuxContainer) updateStateFile() error {
 }
 
 // New returns a newly initialized Pipe for communication between processes
-func newInitPipe() (parent *os.File, child *os.File, err error) {
+func (c *linuxContainer) newInitPipe() (parent *os.File, child *os.File, err error) {
 	fds, err := syscall.Socketpair(syscall.AF_LOCAL, syscall.SOCK_STREAM|syscall.SOCK_CLOEXEC, 0)
 	if err != nil {
 		return nil, nil, err
@@ -392,9 +391,9 @@ func (c *linuxContainer) initializeNetworking(nspid int, networkState *configs.N
 	return nil
 }
 
-func executeSetupCmd(args []string, ppid int, container *configs.Config, process *initConfig, networkState *configs.NetworkState) error {
+func (c *linuxContainer) executeSetupCmd(args []string, ppid int, container *configs.Config, process *initConfig, networkState *configs.NetworkState) error {
 	command := exec.Command(args[0], args[1:]...)
-	parent, child, err := newInitPipe()
+	parent, child, err := c.newInitPipe()
 	if err != nil {
 		return err
 	}

linux_init.go

@@ -30,6 +30,7 @@ const (
 // Process is used for transferring parameters from Exec() to Init()
 type initConfig struct {
 	Args         []string              `json:"args,omitempty"`
+	Env          []string              `json:"env,omitempty"`
 	Config       *configs.Config       `json:"config,omitempty"`
 	NetworkState *configs.NetworkState `json:"network_state,omitempty"`
 }
@@ -43,18 +44,20 @@ func newContainerInit(t initType, pipe *os.File) (initer, error) {
 	if err := json.NewDecoder(pipe).Decode(&config); err != nil {
 		return nil, err
 	}
-	if err := populateProcessEnvironment(config.Config.Env); err != nil {
+	if err := populateProcessEnvironment(config.Env); err != nil {
 		return nil, err
 	}
 	switch t {
 	case initSetns:
 		return &linuxSetnsInit{
 			args:   config.Args,
+			env:    config.Env,
 			config: config.Config,
 		}, nil
 	case initUserns:
 		return &linuxUsernsInit{
 			args:   config.Args,
+			env:    config.Env,
 			config: config.Config,
 		}, nil
 	case initUsernsSideCar:
@@ -65,6 +68,7 @@ func newContainerInit(t initType, pipe *os.File) (initer, error) {
 	case initStandard:
 		return &linuxStandardInit{
 			config: config,
+			env:    config.Env,
 		}, nil
 	}
 	return nil, fmt.Errorf("unknown init type %q", t)

linux_setns_init.go

@@ -13,6 +13,7 @@ import (
 // inside an existing container.
 type linuxSetnsInit struct {
 	args   []string
+	env    []string
 	config *configs.Config
 }
 
@@ -31,5 +32,5 @@ func (l *linuxSetnsInit) Init() error {
 			return err
 		}
 	}
-	return system.Execv(l.args[0], l.args[0:], l.config.Env)
+	return system.Execv(l.args[0], l.args[0:], l.env)
 }

linux_standard_init.go

@@ -16,6 +16,7 @@ import (
 
 type linuxStandardInit struct {
 	config *initConfig
+	env    []string
 }
 
 func (l *linuxStandardInit) Init() error {
@@ -86,5 +87,5 @@ func (l *linuxStandardInit) Init() error {
 	if syscall.Getppid() == 1 {
 		return syscall.Kill(syscall.Getpid(), syscall.SIGKILL)
 	}
-	return system.Execv(l.config.Args[0], l.config.Args[0:], l.config.Config.Env)
+	return system.Execv(l.config.Args[0], l.config.Args[0:], l.env)
 }

linux_userns_init.go

@@ -15,6 +15,7 @@ import (
 
 type linuxUsernsInit struct {
 	args   []string
+	env    []string
 	config *configs.Config
 }
 
@@ -76,5 +77,5 @@ func (l *linuxUsernsInit) Init() error {
 	if syscall.Getppid() == 1 {
 		return syscall.Kill(syscall.Getpid(), syscall.SIGKILL)
 	}
-	return system.Execv(l.args[0], l.args[0:], l.config.Env)
+	return system.Execv(l.args[0], l.args[0:], l.env)
 }

process.go

@@ -1,6 +1,9 @@
 package libcontainer
 
-import "io"
+import (
+	"io"
+	"os/exec"
+)
 
 // Process specifies the configuration and IO for a process inside
 // a container.
@@ -8,6 +11,9 @@ type Process struct {
 	// The command to be run followed by any arguments.
 	Args []string
 
+	// Env specifies the environment variables for the process.
+	Env []string
+
 	// Stdin is a pointer to a reader which provides the standard input stream.
 	Stdin io.Reader
 
@@ -16,4 +22,6 @@ type Process struct {
 
 	// Stderr is a pointer to a writer which receives the standard error stream.
 	Stderr io.Writer
+
+	cmd *exec.Cmd
 }

utils/utils.go

@@ -10,6 +10,10 @@ import (
 	"syscall"
 )
 
+const (
+	exitSignalOffset = 128
+)
+
 // GenerateRandomName returns a new name joined with a prefix.  This size
 // specified is used to truncate the randomly generated value
 func GenerateRandomName(prefix string, size int) (string, error) {
@@ -53,3 +57,12 @@ func CloseExecFrom(minFd int) error {
 	}
 	return nil
 }
+
+// ExitStatus returns the correct exit status for a process based on if it
+// was signaled or existed cleanly.
+func ExitStatus(status syscall.WaitStatus) int {
+	if status.Signaled() {
+		return exitSignalOffset + int(status.Signal())
+	}
+	return status.ExitStatus()
+}