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containersched minicontainer
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| package main | |
| import ( | |
| "fmt" | |
| "os" | |
| "os/exec" | |
| "syscall" | |
| ) | |
| func main() { | |
| switch os.Args[1] { | |
| case "run": | |
| parent() | |
| case "child": | |
| child() | |
| default: | |
| panic("wat should I do") | |
| } | |
| } | |
| func parent() { | |
| cmd := exec.Command("/proc/self/exe", append([]string{"child"}, os.Args[2:]...)...) | |
| cmd.SysProcAttr = &syscall.SysProcAttr{ | |
| Cloneflags: syscall.CLONE_NEWUTS | syscall.CLONE_NEWPID | syscall.CLONE_NEWNS, | |
| } | |
| cmd.Stdin = os.Stdin | |
| cmd.Stdout = os.Stdout | |
| cmd.Stderr = os.Stderr | |
| if err := cmd.Run(); err != nil { | |
| fmt.Println("ERROR", err) | |
| os.Exit(1) | |
| } | |
| } | |
| func child() { | |
| must(syscall.Mount("rootfs", "rootfs", "", syscall.MS_BIND, "")) | |
| must(os.MkdirAll("rootfs/oldrootfs", 0700)) | |
| must(syscall.PivotRoot("rootfs", "rootfs/oldrootfs")) | |
| must(os.Chdir("/")) | |
| cmd := exec.Command(os.Args[2], os.Args[3:]...) | |
| cmd.Stdin = os.Stdin | |
| cmd.Stdout = os.Stdout | |
| cmd.Stderr = os.Stderr | |
| if err := cmd.Run(); err != nil { | |
| fmt.Println("ERROR", err) | |
| os.Exit(1) | |
| } | |
| } | |
| func must(err error) { | |
| if err != nil { | |
| panic(err) | |
| } | |
| } |
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