func ext۰os۰Pipe(fr *frame, args []value) value {
// This is an inlining of linux's os.Pipe.
// func os.Pipe() (r *File, w *File, err error)
var p [2]int
if err := syscall.Pipe2(p[:], syscall.O_CLOEXEC); err != nil {
// TODO(adonovan): fix: return an *os.SyscallError.
return tuple{nil, nil, wrapError(err)}
}
NewFile := fr.i.prog.ImportedPackage("os").Func("NewFile")
r := call(fr.i, fr, 0, NewFile, []value{uintptr(p[0]), "|0"})
w := call(fr.i, fr, 0, NewFile, []value{uintptr(p[1]), "|1"})
return tuple{r, w, wrapError(nil)}
}
// Create a new inotify poller.
// This creates an inotify handler, and an epoll handler.
func newFdPoller(fd int) (*fdPoller, error) {
var errno error
poller := emptyPoller(fd)
defer func() {
if errno != nil {
poller.close()
}
}()
poller.fd = fd
// Create epoll fd
poller.epfd, errno = syscall.EpollCreate1(0)
if poller.epfd == -1 {
return nil, errno
}
// Create pipe; pipe[0] is the read end, pipe[1] the write end.
errno = syscall.Pipe2(poller.pipe[:], syscall.O_NONBLOCK)
if errno != nil {
return nil, errno
}
// Register inotify fd with epoll
event := syscall.EpollEvent{
Fd: int32(poller.fd),
Events: syscall.EPOLLIN,
}
errno = syscall.EpollCtl(poller.epfd, syscall.EPOLL_CTL_ADD, poller.fd, &event)
if errno != nil {
return nil, errno
}
// Register pipe fd with epoll
event = syscall.EpollEvent{
Fd: int32(poller.pipe[0]),
Events: syscall.EPOLLIN,
}
errno = syscall.EpollCtl(poller.epfd, syscall.EPOLL_CTL_ADD, poller.pipe[0], &event)
if errno != nil {
return nil, errno
}
return poller, nil
}
// Pipe returns a connected pair of Files; reads from r return bytes written to w.
// It returns the files and an error, if any.
func Pipe() (r *File, w *File, err error) {
var p [2]int
e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC)
// pipe2 was added in 2.6.27 and our minimum requirement is 2.6.23, so it
// might not be implemented.
if e == syscall.ENOSYS {
// See ../syscall/exec.go for description of lock.
syscall.ForkLock.RLock()
e = syscall.Pipe(p[0:])
if e != nil {
syscall.ForkLock.RUnlock()
return nil, nil, NewSyscallError("pipe", e)
}
syscall.CloseOnExec(p[0])
syscall.CloseOnExec(p[1])
syscall.ForkLock.RUnlock()
} else if e != nil {
return nil, nil, NewSyscallError("pipe2", e)
}
return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil
}
func main() {
runtime.GOMAXPROCS(8)
dec := json.NewDecoder(os.Stdin)
var plan plan
if err := dec.Decode(&plan); err != nil {
panic(fmt.Sprintf("failed to parse plan: %s", err))
}
//fmt.Fprintf(os.Stderr, "plan: %+v\n", plan)
runtime.LockOSThread()
if err := syscall.Setresuid(0, 0, 0); err != nil {
poePanic(err, "setuid failed")
}
if err := InitializeSystemdBus(); err != nil {
poePanic(err, "failed to connect to systemd")
}
runtime.UnlockOSThread()
rootdir, errx := PlaygroundCreate(plan.Base, plan.Compiler.Overlay)
if errx != nil {
poePanic(errx, "playground_create failed")
}
progfile, errx := PlaygroundCopy(rootdir, plan.Source)
if errx != nil {
poePanic(errx, "playground_copy failed")
}
var stdin_fd, stdout_fd, stderr_fd [2]int
if err := syscall.Pipe2(stdin_fd[:], 0); err != nil {
poePanic(err, "pipe2 failed")
}
if err := syscall.Pipe2(stdout_fd[:], syscall.O_DIRECT); err != nil {
poePanic(err, "pipe2 failed")
}
if err := syscall.Pipe2(stderr_fd[:], syscall.O_DIRECT); err != nil {
poePanic(err, "pipe2 failed")
}
pid_, _, err := syscall.Syscall(syscall.SYS_CLONE, uintptr(syscall.SIGCHLD|syscall.CLONE_NEWIPC|syscall.CLONE_NEWNS|syscall.CLONE_NEWPID|syscall.CLONE_NEWUTS|syscall.CLONE_NEWNET), 0, 0)
pid := int(pid_)
if err != 0 {
poePanic(error(err), "clone failed")
} else if pid == 0 {
runtime.LockOSThread()
if err, msg := doChild(rootdir, progfile, plan, stdin_fd, stdout_fd, stderr_fd); err != nil {
fmt.Fprintf(os.Stderr, "%s (%s)", msg, err.Error())
os.Exit(127)
}
// unreachable
} else {
res := doParent(pid, stdin_fd, stdout_fd, stderr_fd)
cleanup()
var buf bytes.Buffer
binary.Write(&buf, binary.LittleEndian, int32(res.result))
binary.Write(&buf, binary.LittleEndian, int32(res.status))
if _, err := os.Stderr.Write(buf.Bytes()); err != nil {
poePanic(err, "stderr write failed")
}
if _, err := os.Stderr.Write([]byte(res.msg)); err != nil {
poePanic(err, "stderr write failed")
}
os.Exit(0)
// unreachable
}
}
