Add a fallback path in case os.Rename fails

For example to trash files on a different filesystem (but would you
really want to do that?)

1 files changed, 59 insertions, 1 deletions

diff --git a/trash.go b/trash.go
index eb9e5f6..cf92cfe 100644
--- a/trash.go
+++ b/trash.go
@@ -3,6 +3,8 @@ package main
 import (
 	"flag"
 	"fmt"
+	"io"
+	"io/fs"
 	"net/url"
 	"os"
 	"path/filepath"
@@ -10,6 +12,62 @@ import (
 	"time"
 )
 
+func mv(src, dst string) error {
+	if err := os.Rename(src, dst); err == nil {
+		return nil
+	}
+	src = filepath.Clean(src)
+	if err := filepath.WalkDir(src, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		relPath := strings.TrimPrefix(path, src)
+		dstPath := filepath.Join(dst, relPath)
+		switch d.Type() {
+		case fs.ModeDir:
+			stat, err := d.Info()
+			if err != nil {
+				return err
+			}
+			return os.Mkdir(dstPath, stat.Mode().Perm())
+		case fs.ModeSymlink:
+			linkTarget, err := os.Readlink(path)
+			if err != nil {
+				return err
+			}
+			return os.Symlink(linkTarget, dstPath)
+		case 0:
+			srcF, err := os.Open(path)
+			if err != nil {
+				return err
+			}
+			defer srcF.Close()
+			stat, err := srcF.Stat()
+			if err != nil {
+				return err
+			}
+			dstF, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE, stat.Mode().Perm())
+			if err != nil {
+				return err
+			}
+			defer dstF.Close()
+			if _, err := io.Copy(dstF, srcF); err != nil {
+				return err
+			}
+			if err := dstF.Close(); err != nil {
+				return err
+			}
+			return nil
+		default:
+			return fmt.Errorf("unknown file type %s", d.Type())
+		}
+	}); err != nil {
+		os.RemoveAll(dst)
+		return err
+	}
+	return os.RemoveAll(src)
+}
+
 func trashFile(fileName, trash, now string) error {
 	absPath, err := filepath.Abs(fileName)
 	if err != nil {
@@ -38,7 +96,7 @@ DeletionDate=%s
 		os.Remove(info.Name())
 		return fmt.Errorf("%s: write trashinfo: %s", fileName, err)
 	}
-	if err := os.Rename(fileName, trash+"/files/"+strings.TrimSuffix(filepath.Base(info.Name()), ".trashinfo")); err != nil {
+	if err := mv(fileName, trash+"/files/"+strings.TrimSuffix(filepath.Base(info.Name()), ".trashinfo")); err != nil {
 		os.Remove(info.Name())
 		return fmt.Errorf("%s: %s", fileName, err)
 	}