Golang WaitStatus.Exited方法代码示例

// waitStatusToStateUpdate converts syscall.WaitStatus to a StateUpdate.
func waitStatusToStateUpdate(ws syscall.WaitStatus) *stateUpdate {
	switch {
	case ws.Exited():
		es := ws.ExitStatus()
		if es == 0 {
			return newExitedStateUpdate(ok)
		}
		return newExitedStateUpdate(newFailure(fmt.Sprint(es)))
	case ws.Signaled():
		msg := fmt.Sprintf("signaled %v", ws.Signal())
		if ws.CoreDump() {
			msg += " (core dumped)"
		}
		return newUnexitedStateUpdate(msg)
	case ws.Stopped():
		msg := fmt.Sprintf("stopped %v", ws.StopSignal())
		trap := ws.TrapCause()
		if trap != -1 {
			msg += fmt.Sprintf(" (trapped %v)", trap)
		}
		return newUnexitedStateUpdate(msg)
	case ws.Continued():
		return newUnexitedStateUpdate("continued")
	default:
		return newUnexitedStateUpdate(fmt.Sprint("unknown status", ws))
	}
}

func (c *CloneParams) CloneFrozen() (int, error) {
	pid := callClone(c)
	// TODO: clone errors?
	c.CommWriter.Close()
	c.stdhandles.Close()
	c.comm = make(chan CommStatus)
	go commReader(c.CommReader, c.comm)

	var status syscall.WaitStatus
	for {
		wpid, err := syscall.Wait4(pid, &status, 0, nil) // TODO: rusage
		if err != nil {
			return -1, os.NewSyscallError("Wait4", err)
		}
		if wpid == pid {
			break
		}
	}
	if status.Stopped() && status.StopSignal() == syscall.SIGTRAP {
		return pid, nil
	}
	if status.Exited() {
		co, ok := <-c.comm
		if ok {
			return -1, childError(co)
		}
		return -1, fmt.Errorf("DAFUQ")
	}
	err := syscall.Kill(pid, syscall.SIGKILL)
	if err != nil {
		return -1, os.NewSyscallError("Kill", err)
	}
	return -1, fmt.Errorf("traps, signals, dafuq is this")
}

// waitStatusToError converts syscall.WaitStatus to an Error.
func waitStatusToError(ws syscall.WaitStatus) error {
	switch {
	case ws.Exited():
		es := ws.ExitStatus()
		if es == 0 {
			return nil
		}
		return errors.New(fmt.Sprint(es))
	case ws.Signaled():
		msg := fmt.Sprintf("signaled %v", ws.Signal())
		if ws.CoreDump() {
			msg += " (core dumped)"
		}
		return errors.New(msg)
	case ws.Stopped():
		msg := fmt.Sprintf("stopped %v", ws.StopSignal())
		trap := ws.TrapCause()
		if trap != -1 {
			msg += fmt.Sprintf(" (trapped %v)", trap)
		}
		return errors.New(msg)
	/*
		case ws.Continued():
			return newUnexitedStateUpdate("continued")
	*/
	default:
		return fmt.Errorf("unknown WaitStatus", ws)
	}
}

func (t *tracerImpl) Run() (err error) {

	if t.cmd.SysProcAttr == nil {
		t.cmd.SysProcAttr = &syscall.SysProcAttr{Ptrace: true}
	} else {
		t.cmd.SysProcAttr.Ptrace = true
	}

	runtime.LockOSThread()

	if err = t.cmd.Start(); err != nil {
		return
	}

	var waitStatus syscall.WaitStatus

	if _, err = syscall.Wait4(t.cmd.Process.Pid, &waitStatus, 0, nil); err != nil {
		return
	}

	if waitStatus.Exited() {
		return
	}

	// Set options to detect our syscalls
	if err = syscall.PtraceSetOptions(t.cmd.Process.Pid, syscall.PTRACE_O_TRACESYSGOOD); err != nil {
		return
	}

	var regsEntry, regsExit syscall.PtraceRegs
	// Get first syscall
	if err = syscall.PtraceGetRegs(t.cmd.Process.Pid, &regsEntry); err != nil {
		return
	}

	var exited bool
	for {
		if exited, err = wait_for_syscall(t.cmd.Process.Pid); exited || err != nil {
			return
		}

		// Get syscall info
		if err = syscall.PtraceGetRegs(t.cmd.Process.Pid, &regsEntry); err != nil {
			return
		}

		// Enter syscall
		t.callback(regsEntry, false)

		if exited, err = wait_for_syscall(t.cmd.Process.Pid); exited || err != nil {
			return
		}

		// Get syscall returned value
		if err = syscall.PtraceGetRegs(t.cmd.Process.Pid, &regsExit); err != nil {
			return
		}
		t.callback(regsExit, true)
	}
}

func (m *Module) IsRunning() bool {
	pid := 0
	if m.Name == "internal:shared" {
		pid = m.SyncProcess.Pid
	} else {
		pid = m.MainProcess.Pid
	}

	var waitstatus syscall.WaitStatus
	wpid, err := syscall.Wait4(pid, &waitstatus, syscall.WNOHANG|syscall.WUNTRACED, nil)
	if err != nil {
		// When would this happen?
		log.Println("Unable to get process wait status:", err)
		// Assume it is not running
		return false
	}

	// If status is not available, the pid is 0.
	if wpid == 0 {
		return true
	}
	if waitstatus.Exited() {
		delete(modules, m.Name)
		return false
	}
	return true
}

func handleSigchld(mpid int) *resultPack {
	for {
		var status syscall.WaitStatus
		var spid int
		var err error
		spid, err = syscall.Wait4(-mpid, &status, syscall.WNOHANG|syscall.WALL, nil)
		if err != nil {
			poePanic(err, "wait4 failed")
		} else if spid == 0 {
			return nil
		}

		if spid == mpid && status.Exited() {
			return &resultPack{POE_SUCCESS, status.ExitStatus(), ""}
		} else if spid == mpid && status.Signaled() {
			return &resultPack{POE_SIGNALED, -1, fmt.Sprintf("Program terminated with signal %d (%s)", int(status.Signal()), status.Signal().String())}
		} else if status.Stopped() {
			e := status >> 16 & 0xff
			switch e {
			case PTRACE_EVENT_SECCOMP:
				if res := handleSyscall(spid); res != nil {
					return res
				}
			case syscall.PTRACE_EVENT_CLONE, syscall.PTRACE_EVENT_FORK, syscall.PTRACE_EVENT_VFORK:
				syscall.PtraceCont(spid, 0)
			default:
				syscall.PtraceCont(spid, int(status.StopSignal()))
			}
		}
	}
}

func printStatus(ws syscall.WaitStatus) string {
	switch {
	case ws.Exited():
		es := ws.ExitStatus()
		if es == 0 {
			return ""
		}
		return fmt.Sprintf("exited %v", es)
	case ws.Signaled():
		msg := fmt.Sprintf("signaled %v", ws.Signal())
		if ws.CoreDump() {
			msg += " (core dumped)"
		}
		return msg
	case ws.Stopped():
		msg := fmt.Sprintf("stopped %v", ws.StopSignal())
		trap := ws.TrapCause()
		if trap != -1 {
			msg += fmt.Sprintf(" (trapped %v)", trap)
		}
		return msg
	case ws.Continued():
		return "continued"
	default:
		return fmt.Sprintf("unknown status %v", ws)
	}
}

// StartProcess kicks off the event loop and forever waits for signals from
// the traced process. This is currently done in a super-silly fashion and will
// hopefully benefit from Go channels/goroutines in the future.
func (p *Process) StartProcess() (ret int) {
	var status syscall.WaitStatus

L:
	for {
		_, err := syscall.Wait4( /*p.Pid*/ -1, &status, 0, nil)
		p.isRunning = false

		switch {
		// status == 0  means terminated??
		case status.Exited() || status == 0 || err != nil:
			ret = status.ExitStatus()
			break L
		case status.Stopped():
			if bp, hit := p.InBreakpoint(); hit {
				p.handleBreakpoint(bp)
			}

		//case status.Continued():
		//case status.CoreDump():
		//case status.Signaled():
		//case status.ExitStatus():
		//case status.StopSignal():
		//case status.TrapCause():
		default:
			// fmt.Printf("Got status: %v\n", status)
		}

		p.Continue()

	}
	return
}

func ChildWaitingFunc(pid int, sig chan *ChildWaitData) {
	var status syscall.WaitStatus
	var rusage syscall.Rusage
	result := &ChildWaitData{}
	for {
		wpid, err := syscall.Wait4(pid, &status, syscall.WUNTRACED|syscall.WCONTINUED, &rusage)
		if wpid != pid {
			continue
		}

		if status.Exited() {
			result.ExitCode = uint32(status.ExitStatus())
			break
		}
		if status.Stopped() {
			result.SuccessCode |= EF_STOPPED
			result.StopSignal = uint32(status.StopSignal())
			syscall.Kill(pid, syscall.SIGKILL)
		}
		if status.Signaled() {
			result.SuccessCode |= EF_KILLED_BY_OTHER
			result.KillSignal = uint32(status.Signal())
			break
		}
		if err != nil {
			break
		}
	}
	result.RusageCpuUser = time.Nanosecond * time.Duration(rusage.Utime.Nano())
	result.RusageCpuKernel = time.Nanosecond * time.Duration(rusage.Stime.Nano())
	sig <- result
	close(sig)
}

// Called on running checks, to determine if they have finished
// running.
//
// If the Check has not finished executing, returns false.
//
// If the Check has been running for longer than its Timeout,
// a SIGTERM (and failing that a SIGKILL) is issued to forcibly
// terminate the rogue Check process. In either case, this returns
// as if the check has not yet finished, and Reap() will need to be
// called again to fully reap the Check
//
// If the Check has finished execution (on its own, or via forced
// termination), it will return true.
//
// Once complete, some additional meta-stats for the check execution
// are appended to the check output, to be submit up to bolo
func (self *Check) Reap() bool {
	pid := self.process.Process.Pid

	var ws syscall.WaitStatus
	status, err := syscall.Wait4(pid, &ws, syscall.WNOHANG, nil)
	if err != nil {
		log.Error("Error waiting on check %s[%d]: %s", self.Name, pid, err.Error())
		return false
	}
	if status == 0 {
		// self to see if we need to sigkill due to failed sigterm
		if time.Now().After(self.started_at.Add(time.Duration(self.Timeout+2) * time.Second)) {
			log.Warn("Check %s[%d] has been running too long, sending SIGKILL", self.Name, pid)
			if err := syscall.Kill(pid, syscall.SIGKILL); err != nil {
				log.Error("Error sending SIGKILL to check %s[%d]: %s", self.Name, pid, err.Error())
			}
			self.sig_kill = true
		}
		// self to see if we need to sigterm due to self timeout expiry
		if !self.sig_kill && time.Now().After(self.started_at.Add(time.Duration(self.Timeout)*time.Second)) {
			log.Warn("Check %s[%d] has been running too long, sending SIGTERM", self.Name, pid)
			if err := syscall.Kill(pid, syscall.SIGTERM); err != nil {
				log.Error("Error sending SIGTERM to check %s[%d]: %s", self.Name, pid, err.Error())
			}
			self.sig_term = true
		}
		return false
	}

	self.ended_at = time.Now()
	self.running = false
	self.duration = time.Since(self.started_at)
	self.latency = self.started_at.Sub(self.next_run)
	self.output = string(self.stdout.Bytes())
	self.err_msg = string(self.stderr.Bytes())

	if ws.Exited() {
		self.rc = ws.ExitStatus()
	} else {
		log.Debug("Check %s[%d] exited abnormally (signaled/stopped). Setting rc to UNKNOWN", self.Name, pid)
		self.rc = UNKNOWN
	}
	if self.rc > UNKNOWN {
		log.Debug("Check %s[%d] returned with an invalid exit code. Setting rc to UNKOWN", self.Name, pid)
		self.rc = UNKNOWN
	}

	self.reschedule()

	if self.ended_at.After(self.next_run) {
		timeout_triggered := "not reached"
		if self.sig_term || self.sig_kill {
			timeout_triggered = "reached"
		}
		log.Warn("Check %s[%d] took %0.3f seconds to run, at interval %d (timeout of %d was %s)",
			self.Name, pid, self.duration.Seconds(), self.Every, self.Timeout, timeout_triggered)
	}
	return true
}

func (self *server) Execute(req *pb.ExecutionRequest, resp pb.Builder_ExecuteServer) error {
	if len(req.Args) == 0 {
		return fmt.Errorf("Request has no command to execute.")
	}

	var args []string
	if len(req.Args) > 1 {
		args = req.Args[1:]
	}

	if req.BuildEnv == nil {
		return fmt.Errorf("No build environment present")
	} else if err := sig.VerifyEnv(req.BuildEnv); err != nil {
		return fmt.Errorf("Failure verifying build environment: %s", err)
	}
	cmd := exec.Command(req.Args[0], args...)
	cmd.Env = convertEnv(req.GetEnv())
	cmd.Stdin = bytes.NewReader(req.Stdin)
	cmd.Dir = req.BuildEnv.Path

	glog.V(1).Infof("Commands to execute %v (build dir: %s)", req, cmd.Dir)

	stdoutPipe, err := cmd.StdoutPipe()
	if err != nil {
		return err
	}

	stderrPipe, err := cmd.StderrPipe()
	if err != nil {
		return err
	}

	if err = cmd.Start(); err != nil {
		return err
	}
	streamReader(stdoutPipe, stderrPipe, resp)
	err = cmd.Wait()

	var status syscall.WaitStatus
	if err != nil {
		if _, ok := err.(*exec.ExitError); ok {
			status = err.(*exec.ExitError).Sys().(syscall.WaitStatus)
		} else {
			return err
		}
	} else if cmd.ProcessState != nil {
		status = cmd.ProcessState.Sys().(syscall.WaitStatus)
	}
	s := &pb.Status{
		CoreDump:   status.CoreDump(),
		Exited:     status.Exited(),
		ExitStatus: int32(status.ExitStatus()),
		Signaled:   status.Signaled(),
		Signal:     int32(status.Signal()),
	}
	resp.Send(&pb.ExecutionResponse{Status: s})
	return nil
}

func NewExternalCmdExit(name string, ws syscall.WaitStatus, pid int) error {
	if ws.Exited() && ws.ExitStatus() == 0 {
		return nil
	}
	if !ws.Stopped() {
		pid = 0
	}
	return ExternalCmdExit{ws, name, pid}
}

func (t *PTracer) handleStopped(pid int, status syscall.WaitStatus) {
	signal := syscall.Signal(0)
	target, err := t.thread(pid)
	if err != nil {
		log.Printf("thread failed: %v", err)
		return
	}

	if !target.attached {
		target.attached = true

		err = syscall.PtraceSetOptions(pid, ptraceOptions)
		if err != nil {
			log.Printf("SetOptions failed, pid=%d, err=%v", pid, err)
			return
		}

	} else if status.Stopped() && status.StopSignal() == syscall.SIGTRAP|ptraceTracesysgoodBit {
		// pid entered Syscall-enter-stop or syscall-exit-stop
		target.syscallStopped()

	} else if status.Stopped() && status.StopSignal() == syscall.SIGTRAP {
		// pid entered PTRACE_EVENT stop
		switch status.TrapCause() {
		case syscall.PTRACE_EVENT_CLONE:
			err := target.handleClone(pid)
			if err != nil {
				log.Printf("clone failed: %v", err)
				return
			}
		default:
			log.Printf("Unknown PTRACE_EVENT %d for pid %d", status.TrapCause(), pid)
		}
	} else if status.Exited() || status.Signaled() {
		// "tracer can safely assume pid will exit"
		t.threadExited(target)
		return
	} else if status.Stopped() {
		// tracee received a non-trace related signal
		signal = status.StopSignal()

		if signal == syscall.SIGSTOP && target.process.detaching {
			t.detachThread(target)
			return
		}
	} else {
		// unknown stop - shouldn't happen!
		log.Printf("Pid %d random stop with status %x", pid, status)
	}

	// Restart stopped caller in syscall trap mode.
	// log.Printf("Restarting pid %d with signal %d", pid, int(signal))
	err = syscall.PtraceSyscall(pid, int(signal))
	if err != nil {
		log.Printf("PtraceSyscall failed, pid=%d, err=%v", pid, err)
	}
}

func execFgCmd(cmd []string, sigStateChanged chan string) {
	cmdStr := strings.Join(cmd, " ")

	// TODO: Extract start process into common function.
	argv0, err := exec.LookPath(cmd[0])
	if err != nil {
		if cmd[0] != "" {
			fmt.Printf("Unknown command: %s\n", cmd[0])
		}
		// Don't execute new process with empty return. Will cause panic.
		sigPrompt <- struct{}{}
		return
	}
	var procAttr os.ProcAttr
	procAttr.Files = []*os.File{os.Stdin, os.Stdout, os.Stderr}

	p, err := os.StartProcess(argv0, cmd, &procAttr)
	if err != nil {
		fmt.Printf("Start process %s, %s failed: %v", err, argv0, cmd)
	}

	for {
		sigChild := make(chan os.Signal)
		defer close(sigChild)
		// SIGCONT not receivable: https://github.com/golang/go/issues/8953
		// This causes some bugs. Eg. CONT signal not captured by handler means subsequent KILL or STOP signals will be ignored by this handler.
		signal.Notify(sigChild, syscall.SIGTSTP, syscall.SIGINT, syscall.SIGCONT, syscall.SIGKILL)
		defer signal.Stop(sigChild)

		var ws syscall.WaitStatus
		// Ignoring error. May return "no child processes" error. Eg. Sending Ctrl-c on `cat` command.
		wpid, _ := syscall.Wait4(p.Pid, &ws, syscall.WUNTRACED, nil)

		if ws.Exited() {
			break
		}
		if ws.Stopped() {
			jobHandler(wpid, runningState, cmdStr)
			jobHandler(wpid, suspendedState, cmdStr)
			// Return prompt when fg has become bg
			sigPrompt <- struct{}{}
		}
		//if ws.Continued() {
		//	state = contState
		//}
		if ws == 9 {
			jobHandler(wpid, killedState, cmdStr)
			break
		}
	}

	p.Wait()
	sigPrompt <- struct{}{}
}

func execBgCmd(cmd []string, sigStateChanged chan string) {
	cmdStr := strings.Join(cmd, " ")

	argv0, err := exec.LookPath(cmd[0])
	if err != nil {
		if cmd[0] != "" {
			fmt.Printf("Unknown command: %s\n", cmd[0])
		}
		sigPrompt <- struct{}{}
		return
	}
	var procAttr os.ProcAttr
	procAttr.Files = []*os.File{os.Stdin, os.Stdout, os.Stderr}

	p, err := os.StartProcess(argv0, cmd, &procAttr)
	if err != nil {
		fmt.Printf("Start process %s, %s failed: %v", err, argv0, cmd)
	}
	jobHandler(p.Pid, runningState, cmdStr)
	sigPrompt <- struct{}{}

	//FIXME: Bg processes should not receive keyboard signals sent to fg process.

	for {
		sigChild := make(chan os.Signal)
		defer close(sigChild)
		signal.Notify(sigChild, syscall.SIGCHLD)
		defer signal.Stop(sigChild)

		var ws syscall.WaitStatus
		wpid, _ := syscall.Wait4(p.Pid, &ws, syscall.WUNTRACED, nil)

		if ws.Exited() {
			jobHandler(wpid, doneState, cmdStr)
			break
		}
		if ws.Stopped() {
			jobHandler(wpid, suspendedState, cmdStr)
			sigPrompt <- struct{}{}
		}
		//if ws.Continued() {
		//	state = contState
		//}
		if ws == 9 {
			jobHandler(wpid, killedState, cmdStr)
			break
		}
	}

	p.Wait()
	sigPrompt <- struct{}{}
}