Fix run command race (#1470)

* Use exec.CommandContext to simplfy timeout handling

And fixing the data races which can be identified by the added tests when -race enabled.

* Use sleep commmand instead of reading from stdin

* Make the error handling go-esque
This commit is contained in:
Mura Li 2017-11-13 08:51:45 -06:00 committed by Lunny Xiao
parent e9728bf3b4
commit f4d12f8d97
2 changed files with 33 additions and 22 deletions

View File

@ -6,13 +6,12 @@ package process
import (
"bytes"
"context"
"errors"
"fmt"
"os/exec"
"sync"
"time"
"code.gitea.io/gitea/modules/log"
)
// TODO: This packages still uses a singleton for the Manager.
@ -101,7 +100,10 @@ func (pm *Manager) ExecDirEnv(timeout time.Duration, dir, desc string, env []str
stdOut := new(bytes.Buffer)
stdErr := new(bytes.Buffer)
cmd := exec.Command(cmdName, args...)
ctx, cancel := context.WithTimeout(context.Background(), timeout)
defer cancel()
cmd := exec.CommandContext(ctx, cmdName, args...)
cmd.Dir = dir
cmd.Env = env
cmd.Stdout = stdOut
@ -111,30 +113,14 @@ func (pm *Manager) ExecDirEnv(timeout time.Duration, dir, desc string, env []str
}
pid := pm.Add(desc, cmd)
done := make(chan error)
go func() {
done <- cmd.Wait()
}()
var err error
select {
case <-time.After(timeout):
if errKill := pm.Kill(pid); errKill != nil {
log.Error(4, "exec(%d:%s) failed to kill: %v", pid, desc, errKill)
}
<-done
return "", "", ErrExecTimeout
case err = <-done:
}
err := cmd.Wait()
pm.Remove(pid)
if err != nil {
out := fmt.Errorf("exec(%d:%s) failed: %v stdout: %v stderr: %v", pid, desc, err, stdOut, stdErr)
return stdOut.String(), stdErr.String(), out
err = fmt.Errorf("exec(%d:%s) failed: %v(%v) stdout: %v stderr: %v", pid, desc, err, ctx.Err(), stdOut, stdErr)
}
return stdOut.String(), stdErr.String(), nil
return stdOut.String(), stdErr.String(), err
}
// Kill and remove a process from list.

View File

@ -3,6 +3,7 @@ package process
import (
"os/exec"
"testing"
"time"
"github.com/stretchr/testify/assert"
)
@ -31,3 +32,27 @@ func TestManager_Remove(t *testing.T) {
_, exists := pm.Processes[pid2]
assert.False(t, exists, "PID %d is in the list but shouldn't", pid2)
}
func TestExecTimeoutNever(t *testing.T) {
// TODO Investigate how to improve the time elapsed per round.
maxLoops := 10
for i := 1; i < maxLoops; i++ {
_, stderr, err := GetManager().ExecTimeout(5*time.Second, "ExecTimeout", "git", "--version")
if err != nil {
t.Fatalf("git --version: %v(%s)", err, stderr)
}
}
}
func TestExecTimeoutAlways(t *testing.T) {
maxLoops := 100
for i := 1; i < maxLoops; i++ {
_, stderr, err := GetManager().ExecTimeout(100*time.Microsecond, "ExecTimeout", "sleep", "5")
// TODO Simplify logging and errors to get precise error type. E.g. checking "if err != context.DeadlineExceeded".
if err == nil {
t.Fatalf("sleep 5 secs: %v(%s)", err, stderr)
}
}
}