Allow cleanup handlers to filter the exit code

cmd/restic/cleanup.go

@@ -11,7 +11,7 @@ import (
 
 var cleanupHandlers struct {
 	sync.Mutex
-	list []func() error
+	list []func(code int) (int, error)
 	done bool
 	ch   chan os.Signal
 }
@@ -25,7 +25,7 @@ func init() {
 // AddCleanupHandler adds the function f to the list of cleanup handlers so
 // that it is executed when all the cleanup handlers are run, e.g. when SIGINT
 // is received.
-func AddCleanupHandler(f func() error) {
+func AddCleanupHandler(f func(code int) (int, error)) {
 	cleanupHandlers.Lock()
 	defer cleanupHandlers.Unlock()
 
@@ -36,22 +36,24 @@ func AddCleanupHandler(f func() error) {
 }
 
 // RunCleanupHandlers runs all registered cleanup handlers
-func RunCleanupHandlers() {
+func RunCleanupHandlers(code int) int {
 	cleanupHandlers.Lock()
 	defer cleanupHandlers.Unlock()
 
 	if cleanupHandlers.done {
-		return
+		return code
 	}
 	cleanupHandlers.done = true
 
 	for _, f := range cleanupHandlers.list {
-		err := f()
+		var err error
+		code, err = f(code)
 		if err != nil {
 			Warnf("error in cleanup handler: %v\n", err)
 		}
 	}
 	cleanupHandlers.list = nil
+	return code
 }
 
 // CleanupHandler handles the SIGINT signals.
@@ -75,6 +77,6 @@ func CleanupHandler(c <-chan os.Signal) {
 // Exit runs the cleanup handlers and then terminates the process with the
 // given exit code.
 func Exit(code int) {
-	RunCleanupHandlers()
+	code = RunCleanupHandlers(code)
 	os.Exit(code)
 }

cmd/restic/cmd_check.go

@@ -197,9 +197,9 @@ func runCheck(opts CheckOptions, gopts GlobalOptions, args []string) error {
 	}
 
 	cleanup := prepareCheckCache(opts, &gopts)
-	AddCleanupHandler(func() error {
+	AddCleanupHandler(func(code int) (int, error) {
 		cleanup()
-		return nil
+		return code, nil
 	})
 
 	repo, err := OpenRepository(gopts)

cmd/restic/cmd_mount.go

@@ -158,13 +158,13 @@ func runMount(opts MountOptions, gopts GlobalOptions, args []string) error {
 		}
 	}
 
-	AddCleanupHandler(func() error {
+	AddCleanupHandler(func(code int) (int, error) {
 		debug.Log("running umount cleanup handler for mount at %v", mountpoint)
 		err := umount(mountpoint)
 		if err != nil {
 			Warnf("unable to umount (maybe already umounted or still in use?): %v\n", err)
 		}
-		return nil
+		return code, nil
 	})
 
 	c, err := systemFuse.Mount(mountpoint, mountOptions...)

cmd/restic/global.go

@@ -97,11 +97,11 @@ var isReadingPassword bool
 func init() {
 	var cancel context.CancelFunc
 	globalOptions.ctx, cancel = context.WithCancel(context.Background())
-	AddCleanupHandler(func() error {
+	AddCleanupHandler(func(code int) (int, error) {
 		// Must be called before the unlock cleanup handler to ensure that the latter is
 		// not blocked due to limited number of backend connections, see #1434
 		cancel()
-		return nil
+		return code, nil
 	})
 
 	f := cmdRoot.PersistentFlags()
@@ -199,20 +199,20 @@ func restoreTerminal() {
 		return
 	}
 
-	AddCleanupHandler(func() error {
+	AddCleanupHandler(func(code int) (int, error) {
 		// Restoring the terminal configuration while restic runs in the
 		// background, causes restic to get stopped on unix systems with
 		// a SIGTTOU signal. Thus only restore the terminal settings if
 		// they might have been modified, which is the case while reading
 		// a password.
 		if !isReadingPassword {
-			return nil
+			return code, nil
 		}
 		err := checkErrno(term.Restore(fd, state))
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "unable to restore terminal state: %v\n", err)
 		}
-		return err
+		return code, err
 	})
 }
 

cmd/restic/global_debug.go

@@ -84,9 +84,9 @@ func runDebug() error {
 	}
 
 	if prof != nil {
-		AddCleanupHandler(func() error {
+		AddCleanupHandler(func(code int) (int, error) {
 			prof.Stop()
-			return nil
+			return code, nil
 		})
 	}
 

cmd/restic/lock.go

@@ -119,7 +119,7 @@ func unlockRepo(lock *restic.Lock) {
 	debug.Log("unable to find lock %v in the global list of locks, ignoring", lock)
 }
 
-func unlockAll() error {
+func unlockAll(code int) (int, error) {
 	globalLocks.Lock()
 	defer globalLocks.Unlock()
 
@@ -127,11 +127,11 @@ func unlockAll() error {
 	for _, lock := range globalLocks.locks {
 		if err := lock.Unlock(); err != nil {
 			debug.Log("error while unlocking: %v", err)
-			return err
+			return code, err
 		}
 		debug.Log("successfully removed lock")
 	}
 	globalLocks.locks = globalLocks.locks[:0]
 
-	return nil
+	return code, nil
 }