refactor(thothctl): share Pi lifecycle lock

tools/thothctl/internal/config/installation.go

@@ -246,6 +246,10 @@ func (i Installation) UpdateStatePath() string {
 	return filepath.Join(i.ControlDirectory(), "update-state.json")
 }
 
+func (i Installation) RestartStatePath() string {
+	return filepath.Join(i.ControlDirectory(), "restart-state.json")
+}
+
 // ProjectName is stable for one installation and avoids collisions between different checkouts.
 func (i Installation) ProjectName() string {
 	sum := sha256.Sum256([]byte(i.Path))

tools/thothctl/internal/config/installation_test.go

@@ -224,6 +224,9 @@ func TestInstallationControlPathsAreIsolatedForDescriptorsSharingOneCheckout(t *
 		if filepath.Dir(installation.UpdateStatePath()) != filepath.Dir(installation.CurrentImageOverridePath()) {
 			t.Fatalf("state %q and selector %q do not share one installation control directory", installation.UpdateStatePath(), installation.CurrentImageOverridePath())
 		}
+		if got, want := installation.RestartStatePath(), filepath.Join(installation.ControlDirectory(), "restart-state.json"); got != want {
+			t.Fatalf("RestartStatePath() = %q, want %q", got, want)
+		}
 	}
 }
 

tools/thothctl/internal/pi/state.go

@@ -180,13 +180,17 @@ type updateLock struct {
 	metadata string
 }
 
-var ErrLockHeld = errors.New("another Pi update or rollback is already in progress")
+var ErrLockHeld = errors.New("another Pi update, restart, or rollback is already in progress")
+
+func lifecycleLockPath(statePath string) string {
+	return filepath.Join(filepath.Dir(statePath), "pi-lifecycle.lock")
+}
 
 func acquireLock(statePath string) (*updateLock, error) {
 	if err := os.MkdirAll(filepath.Dir(statePath), 0o700); err != nil {
 		return nil, errors.New("could not create Pi update recovery directory")
 	}
-	path := statePath + ".lock"
+	path := lifecycleLockPath(statePath)
 	file := flock.New(path, flock.SetPermissions(0o600))
 	locked, err := file.TryLock()
 	if err != nil {

tools/thothctl/internal/pi/state_test.go

@@ -24,6 +24,20 @@ func TestAdvisoryLockRejectsAConcurrentOwner(t *testing.T) {
 	}
 }
 
+func TestUpdateAndRestartStatePathsShareOneLifecycleLock(t *testing.T) {
+	dir := t.TempDir()
+	first, err := acquireLock(filepath.Join(dir, "update-state.json"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer first.Release()
+
+	second, err := acquireLock(filepath.Join(dir, "restart-state.json"))
+	if !errors.Is(err, ErrLockHeld) || second != nil {
+		t.Fatalf("second lock = %#v, %v; want nil, ErrLockHeld", second, err)
+	}
+}
+
 func TestAdvisoryLockCrashReleasesAndReacquires(t *testing.T) {
 	statePath := filepath.Join(t.TempDir(), "update-state.json")
 	if os.Getenv("THOTHCTL_LOCK_CRASH_HELPER") == "1" {
@@ -47,10 +61,11 @@ func TestAdvisoryLockCrashReleasesAndReacquires(t *testing.T) {
 
 func TestAdvisoryLockIgnoresPartialDiagnosticMetadata(t *testing.T) {
 	statePath := filepath.Join(t.TempDir(), "update-state.json")
-	if err := os.WriteFile(statePath+".lock", nil, 0o600); err != nil {
+	lockPath := lifecycleLockPath(statePath)
+	if err := os.WriteFile(lockPath, nil, 0o600); err != nil {
 		t.Fatal(err)
 	}
-	if err := os.WriteFile(statePath+".lock.owner.json", []byte("{partial"), 0o600); err != nil {
+	if err := os.WriteFile(lockPath+".owner.json", []byte("{partial"), 0o600); err != nil {
 		t.Fatal(err)
 	}
 	lock, err := acquireLock(statePath)