lib/syncthing: Prevent hangup on error during startup (fixes #6043) (#6047)

This commit is contained in:
Simon Frei 2019-10-16 10:10:42 +02:00 committed by GitHub
parent 7b33294955
commit b8907b49f9
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 90 additions and 29 deletions

View File

@ -647,7 +647,9 @@ func syncthingMain(runtimeOptions RuntimeOptions) {
} }
} }
app.Start() if err := app.Start(); err != nil {
os.Exit(int(syncthing.ExitError))
}
cleanConfigDirectory() cleanConfigDirectory()

View File

@ -73,14 +73,13 @@ type App struct {
opts Options opts Options
exitStatus ExitStatus exitStatus ExitStatus
err error err error
startOnce sync.Once
stopOnce sync.Once stopOnce sync.Once
stop chan struct{} stop chan struct{}
stopped chan struct{} stopped chan struct{}
} }
func New(cfg config.Wrapper, ll *db.Lowlevel, evLogger events.Logger, cert tls.Certificate, opts Options) *App { func New(cfg config.Wrapper, ll *db.Lowlevel, evLogger events.Logger, cert tls.Certificate, opts Options) *App {
return &App{ a := &App{
cfg: cfg, cfg: cfg,
ll: ll, ll: ll,
evLogger: evLogger, evLogger: evLogger,
@ -89,25 +88,21 @@ func New(cfg config.Wrapper, ll *db.Lowlevel, evLogger events.Logger, cert tls.C
stop: make(chan struct{}), stop: make(chan struct{}),
stopped: make(chan struct{}), stopped: make(chan struct{}),
} }
} close(a.stopped) // Hasn't been started, so shouldn't block on Wait.
return a
// Run does the same as start, but then does not return until the app stops. It
// is equivalent to calling Start and then Wait.
func (a *App) Run() ExitStatus {
a.Start()
return a.Wait()
} }
// Start executes the app and returns once all the startup operations are done, // Start executes the app and returns once all the startup operations are done,
// e.g. the API is ready for use. // e.g. the API is ready for use.
func (a *App) Start() { // Must be called once only.
a.startOnce.Do(func() { func (a *App) Start() error {
if err := a.startup(); err != nil { if err := a.startup(); err != nil {
a.stopWithErr(ExitError, err) a.stopWithErr(ExitError, err)
return return err
} }
a.stopped = make(chan struct{})
go a.run() go a.run()
}) return nil
} }
func (a *App) startup() error { func (a *App) startup() error {
@ -378,7 +373,8 @@ func (a *App) run() {
close(a.stopped) close(a.stopped)
} }
// Wait blocks until the app stops running. // Wait blocks until the app stops running. Also returns if the app hasn't been
// started yet.
func (a *App) Wait() ExitStatus { func (a *App) Wait() ExitStatus {
<-a.stopped <-a.stopped
return a.exitStatus return a.exitStatus
@ -388,11 +384,11 @@ func (a *App) Wait() ExitStatus {
// for the app to stop before returning. // for the app to stop before returning.
func (a *App) Error() error { func (a *App) Error() error {
select { select {
case <-a.stopped: case <-a.stop:
return nil return a.err
default: default:
} }
return a.err return nil
} }
// Stop stops the app and sets its exit status to given reason, unless the app // Stop stops the app and sets its exit status to given reason, unless the app
@ -403,12 +399,8 @@ func (a *App) Stop(stopReason ExitStatus) ExitStatus {
func (a *App) stopWithErr(stopReason ExitStatus, err error) ExitStatus { func (a *App) stopWithErr(stopReason ExitStatus, err error) ExitStatus {
a.stopOnce.Do(func() { a.stopOnce.Do(func() {
// ExitSuccess is the default value for a.exitStatus. If another status
// was already set, ignore the stop reason given as argument to Stop.
if a.exitStatus == ExitSuccess {
a.exitStatus = stopReason a.exitStatus = stopReason
a.err = err a.err = err
}
close(a.stop) close(a.stop)
}) })
return a.exitStatus return a.exitStatus

View File

@ -7,20 +7,36 @@
package syncthing package syncthing
import ( import (
"io/ioutil"
"os"
"path/filepath"
"testing" "testing"
"time"
"github.com/syncthing/syncthing/lib/config" "github.com/syncthing/syncthing/lib/config"
"github.com/syncthing/syncthing/lib/events" "github.com/syncthing/syncthing/lib/events"
"github.com/syncthing/syncthing/lib/protocol" "github.com/syncthing/syncthing/lib/protocol"
"github.com/syncthing/syncthing/lib/tlsutil"
) )
func tempCfgFilename(t *testing.T) string {
t.Helper()
f, err := ioutil.TempFile("", "syncthing-testConfig-")
if err != nil {
t.Fatal(err)
}
defer f.Close()
return f.Name()
}
func TestShortIDCheck(t *testing.T) { func TestShortIDCheck(t *testing.T) {
cfg := config.Wrap("/tmp/test", config.Configuration{ cfg := config.Wrap(tempCfgFilename(t), config.Configuration{
Devices: []config.DeviceConfiguration{ Devices: []config.DeviceConfiguration{
{DeviceID: protocol.DeviceID{8, 16, 24, 32, 40, 48, 56, 0, 0}}, {DeviceID: protocol.DeviceID{8, 16, 24, 32, 40, 48, 56, 0, 0}},
{DeviceID: protocol.DeviceID{8, 16, 24, 32, 40, 48, 56, 1, 1}}, // first 56 bits same, differ in the first 64 bits {DeviceID: protocol.DeviceID{8, 16, 24, 32, 40, 48, 56, 1, 1}}, // first 56 bits same, differ in the first 64 bits
}, },
}, events.NoopLogger) }, events.NoopLogger)
defer os.Remove(cfg.ConfigPath())
if err := checkShortIDs(cfg); err != nil { if err := checkShortIDs(cfg); err != nil {
t.Error("Unexpected error:", err) t.Error("Unexpected error:", err)
@ -37,3 +53,54 @@ func TestShortIDCheck(t *testing.T) {
t.Error("Should have gotten an error") t.Error("Should have gotten an error")
} }
} }
func TestStartupFail(t *testing.T) {
tmpDir, err := ioutil.TempDir("", "syncthing-TestStartupFail-")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(tmpDir)
cert, err := tlsutil.NewCertificate(filepath.Join(tmpDir, "cert"), filepath.Join(tmpDir, "key"), "syncthing")
if err != nil {
t.Fatal(err)
}
id := protocol.NewDeviceID(cert.Certificate[0])
conflID := protocol.DeviceID{}
copy(conflID[:8], id[:8])
cfg := config.Wrap(tempCfgFilename(t), config.Configuration{
Devices: []config.DeviceConfiguration{
{DeviceID: id},
{DeviceID: conflID},
},
}, events.NoopLogger)
defer os.Remove(cfg.ConfigPath())
app := New(cfg, nil, events.NoopLogger, cert, Options{})
startErr := app.Start()
if startErr == nil {
t.Fatal("Expected an error from Start, got nil")
}
done := make(chan struct{})
var waitE ExitStatus
go func() {
waitE = app.Wait()
close(done)
}()
select {
case <-time.After(time.Second):
t.Fatal("Wait did not return within 1s")
case <-done:
}
if waitE != ExitError {
t.Errorf("Got exit status %v, expected %v", waitE, ExitError)
}
if err = app.Error(); err != startErr {
t.Errorf(`Got different errors "%v" from Start and "%v" from Error`, startErr, err)
}
}