RSDK-9591 - Add Kill to ManagedProcess

pexec/managed_process.go

@@ -32,6 +32,10 @@ type ManagedProcess interface {
 	// there's any system level issue stopping the process.
 	Stop() error
 
+	// Kill will attempt to kill the process group and not wait for completion. Only use this if
+	// comfortable with leaking resources (in cases where exiting the program as quickly as possible is desired).
+	Kill()
+
 	// Status return nil when the process is both alive and owned.
 	// If err is non-nil, process may be a) alive but not owned or b) dead.
 	Status() error
@@ -432,3 +436,29 @@ func (p *managedProcess) Stop() error {
 	}
 	return errors.Errorf("non-successful exit code: %d", p.cmd.ProcessState.ExitCode())
 }
+
+func (p *managedProcess) Kill() {
+	// Minimally hold a lock here so that we can signal the
+	// management goroutine to stop. We will attempt to kill the
+	// process even if p.stopped is true.
+	p.mu.Lock()
+	if !p.stopped {
+		close(p.killCh)
+		p.stopped = true
+	}
+
+	if p.cmd == nil {
+		p.mu.Unlock()
+		return
+	}
+	p.mu.Unlock()
+
+	// Since p.cmd is mutex guarded and we just signaled the manage
+	// goroutine to stop, no new Start can happen and therefore
+	// p.cmd can no longer be modified rendering it safe to read
+	// without a lock held.
+	// We are intentionally not checking the error here, we are already
+	// in a bad state.
+	//nolint:errcheck,gosec
+	p.forceKill()
+}

pexec/managed_process_test.go

@@ -702,3 +702,5 @@ func (fp *fakeProcess) UnixPid() (int, error) {
 in reality tests should just depend on the methods they rely on. UnixPid is not one
 of those methods (for better or worse)`)
 }
+
+func (fp *fakeProcess) Kill() {}

pexec/managed_process_unix.go

@@ -4,6 +4,7 @@ package pexec
 
 import (
 	"os"
+	"os/exec"
 	"os/user"
 	"strconv"
 	"syscall"
@@ -126,6 +127,14 @@ func (p *managedProcess) kill() (bool, error) {
 	return forceKilled, nil
 }
 
+// forceKill kills everything in the process group. This will not wait for completion and may result in a zombie process.
+func (p *managedProcess) forceKill() error {
+	pidStr := strconv.Itoa(-p.cmd.Process.Pid)
+	p.logger.Infof("killing entire process group %d", p.cmd.Process.Pid)
+	//nolint:gosec
+	return exec.Command("kill", "-9", pidStr).Start()
+}
+
 func isWaitErrUnknown(err string, forceKilled bool) bool {
 	// This can easily happen if the process does not handle interrupts gracefully
 	// and it won't provide us any exit code info.

pexec/managed_process_windows.go

@@ -25,7 +25,6 @@ func parseSignal(sigStr, name string) (syscall.Signal, error) {
 	return 0, errors.New("signals not supported on Windows")
 }
 
-
 func (p *managedProcess) sysProcAttr() (*syscall.SysProcAttr, error) {
 	ret := &syscall.SysProcAttr{
 		CreationFlags: syscall.CREATE_NEW_PROCESS_GROUP,
@@ -107,6 +106,13 @@ func (p *managedProcess) kill() (bool, error) {
 	return forceKilled, nil
 }
 
+// forceKill kills everything in the process tree. This will not wait for completion and may result in a zombie process.
+func (p *managedProcess) forceKill() error {
+	pidStr := strconv.Itoa(p.cmd.Process.Pid)
+	p.logger.Infof("force killing entire process tree %d", p.cmd.Process.Pid)
+	return exec.Command("taskkill", "/t", "/f", "/pid", pidStr).Start()
+}
+
 func isWaitErrUnknown(err string, forceKilled bool) bool {
 	if !forceKilled {
 		return false