1 files changed, 24 insertions, 4 deletions
diff --git a/misc/dashboard/builder/exec.go b/misc/dashboard/builder/exec.go
index 802d5f079..6ebe7b8bf 100644
--- a/misc/dashboard/builder/exec.go
+++ b/misc/dashboard/builder/exec.go
@@ -6,14 +6,16 @@ package main
 
 import (
 	"bytes"
+	"fmt"
 	"io"
 	"log"
 	"os"
 	"os/exec"
+	"time"
 )
 
 // run is a simple wrapper for exec.Run/Close
-func run(envv []string, dir string, argv ...string) error {
+func run(timeout time.Duration, envv []string, dir string, argv ...string) error {
 	if *verbose {
 		log.Println("run", argv)
 	}
@@ -21,7 +23,10 @@ func run(envv []string, dir string, argv ...string) error {
 	cmd.Dir = dir
 	cmd.Env = envv
 	cmd.Stderr = os.Stderr
-	return cmd.Run()
+	if err := cmd.Start(); err != nil {
+		return err
+	}
+	return waitWithTimeout(timeout, cmd)
 }
 
 // runLog runs a process and returns the combined stdout/stderr, 
@@ -29,7 +34,7 @@ func run(envv []string, dir string, argv ...string) error {
 // process combined stdout and stderr output, exit status and error.
 // The error returned is nil, if process is started successfully,
 // even if exit status is not successful.
-func runLog(envv []string, logfile, dir string, argv ...string) (string, int, error) {
+func runLog(timeout time.Duration, envv []string, logfile, dir string, argv ...string) (string, int, error) {
 	if *verbose {
 		log.Println("runLog", argv)
 	}
@@ -56,8 +61,23 @@ func runLog(envv []string, logfile, dir string, argv ...string) (string, int, er
 		return "", 1, startErr
 	}
 	exitStatus := 0
-	if err := cmd.Wait(); err != nil {
+	if err := waitWithTimeout(timeout, cmd); err != nil {
 		exitStatus = 1 // TODO(bradfitz): this is fake. no callers care, so just return a bool instead.
 	}
 	return b.String(), exitStatus, nil
 }
+
+func waitWithTimeout(timeout time.Duration, cmd *exec.Cmd) error {
+	errc := make(chan error, 1)
+	go func() {
+		errc <- cmd.Wait()
+	}()
+	var err error
+	select {
+	case <-time.After(timeout):
+		cmd.Process.Kill()
+		err = fmt.Errorf("timed out after %v", timeout)
+	case err = <-errc:
+	}
+	return err
+}