| // +build linux |
| |
| package main |
| |
| import ( |
| "encoding/json" |
| "fmt" |
| "os" |
| "path" |
| "strconv" |
| "strings" |
| |
| "github.com/Sirupsen/logrus" |
| "github.com/codegangsta/cli" |
| "github.com/opencontainers/specs" |
| ) |
| |
| var execCommand = cli.Command{ |
| Name: "exec", |
| Usage: "execute new process inside the container", |
| Flags: []cli.Flag{ |
| cli.StringFlag{ |
| Name: "console", |
| Usage: "specify the pty slave path for use with the container", |
| }, |
| cli.StringFlag{ |
| Name: "cwd", |
| Usage: "current working directory in the container", |
| }, |
| cli.StringSliceFlag{ |
| Name: "env, e", |
| Usage: "set environment variables", |
| }, |
| cli.BoolFlag{ |
| Name: "tty, t", |
| Usage: "allocate a pseudo-TTY", |
| }, |
| cli.StringFlag{ |
| Name: "user, u", |
| Usage: "UID (format: <uid>[:<gid>])", |
| }, |
| cli.StringFlag{ |
| Name: "process,p", |
| Usage: "path to the process.json", |
| }, |
| cli.BoolFlag{ |
| Name: "detach,d", |
| Usage: "detach from the container's process", |
| }, |
| cli.StringFlag{ |
| Name: "pid-file", |
| Value: "", |
| Usage: "specify the file to write the process id to", |
| }, |
| }, |
| Action: func(context *cli.Context) { |
| if os.Geteuid() != 0 { |
| logrus.Fatal("runc should be run as root") |
| } |
| status, err := execProcess(context) |
| if err != nil { |
| logrus.Fatalf("exec failed: %v", err) |
| } |
| os.Exit(status) |
| }, |
| } |
| |
| func execProcess(context *cli.Context) (int, error) { |
| container, err := getContainer(context) |
| if err != nil { |
| return -1, err |
| } |
| |
| var ( |
| detach = context.Bool("detach") |
| rootfs = container.Config().Rootfs |
| ) |
| |
| p, err := getProcess(context, path.Dir(rootfs)) |
| if err != nil { |
| return -1, err |
| } |
| |
| return runProcess(container, p, nil, context.String("console"), context.String("pid-file"), detach) |
| |
| } |
| |
| func getProcess(context *cli.Context, bundle string) (*specs.Process, error) { |
| if path := context.String("process"); path != "" { |
| f, err := os.Open(path) |
| if err != nil { |
| return nil, err |
| } |
| defer f.Close() |
| var p specs.Process |
| if err := json.NewDecoder(f).Decode(&p); err != nil { |
| return nil, err |
| } |
| return &p, nil |
| } |
| // process via cli flags |
| if err := os.Chdir(bundle); err != nil { |
| return nil, err |
| } |
| spec, err := loadSpec(specConfig) |
| if err != nil { |
| return nil, err |
| } |
| p := spec.Process |
| p.Args = context.Args()[1:] |
| // override the cwd, if passed |
| if context.String("cwd") != "" { |
| p.Cwd = context.String("cwd") |
| } |
| // append the passed env variables |
| for _, e := range context.StringSlice("env") { |
| p.Env = append(p.Env, e) |
| } |
| // set the tty |
| if context.IsSet("tty") { |
| p.Terminal = context.Bool("tty") |
| } |
| // override the user, if passed |
| if context.String("user") != "" { |
| u := strings.SplitN(context.String("user"), ":", 2) |
| if len(u) > 1 { |
| gid, err := strconv.Atoi(u[1]) |
| if err != nil { |
| return nil, fmt.Errorf("parsing %s as int for gid failed: %v", u[1], err) |
| } |
| p.User.GID = uint32(gid) |
| } |
| uid, err := strconv.Atoi(u[0]) |
| if err != nil { |
| return nil, fmt.Errorf("parsing %s as int for uid failed: %v", u[0], err) |
| } |
| p.User.UID = uint32(uid) |
| } |
| return &p, nil |
| } |