add main file

executer.go

@@ -0,0 +1,69 @@
+package executer
+
+import (
+	"errors"
+	"os/exec"
+	"time"
+)
+
+var ErrTimeout = errors.New("operation timed out")
+
+type Job struct {
+	Cmd *exec.Cmd
+	Err chan error
+}
+
+type Worker struct {
+	Jobs    chan Job
+	Timeout time.Duration
+}
+
+func NewJob(e *exec.Cmd) Job {
+	return Job{
+		Cmd: e,
+		Err: make(chan error),
+	}
+}
+
+func NewWorker(timeout time.Duration) *Worker {
+	w := &Worker{
+		Jobs:    make(chan Job, 1),
+		Timeout: timeout,
+	}
+	// start worker routine
+	go w.run()
+	return w
+}
+
+// runs in own goroutine
+func (e *Worker) run() {
+	var done chan error
+
+	if e.Timeout != 0 {
+		done = make(chan error)
+		defer close(done)
+	}
+
+	for j := range e.Jobs {
+		if e.Timeout == 0 {
+			// run synchronously
+			j.Err <- j.Cmd.Run()
+		} else {
+			// run asyncly and timeout
+			go func() {
+				done <- j.Cmd.Run()
+			}()
+
+			select {
+			case err := <-done:
+				j.Err <- err
+			case <-time.After(e.Timeout):
+				j.Err <- j.Cmd.Process.Kill()
+				j.Err <- ErrTimeout
+			}
+		}
+
+		// signal done
+		close(j.Err)
+	}
+}