Esa Kataja
22b3a73109
Centralize all move helpers through a single safeRename function that stats the destination first and refuses to overwrite (bug #14), and falls back to copy+fsync+remove when os.Rename returns EXDEV across mounted filesystems (bug #13). Drops the dead MoveToOutput helper.
99 lines
2.4 KiB
Go
99 lines
2.4 KiB
Go
package mover
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"io"
|
|
"os"
|
|
"path/filepath"
|
|
"syscall"
|
|
)
|
|
|
|
// safeRename moves src to dst. Refuses to overwrite an existing dst.
|
|
// Falls back to copy+remove on EXDEV (cross-device) errors.
|
|
func safeRename(src, dst string) error {
|
|
if _, err := os.Stat(dst); err == nil {
|
|
return fmt.Errorf("destination %s already exists", dst)
|
|
} else if !errors.Is(err, os.ErrNotExist) {
|
|
return fmt.Errorf("stat destination %s: %w", dst, err)
|
|
}
|
|
|
|
err := os.Rename(src, dst)
|
|
if err == nil {
|
|
return nil
|
|
}
|
|
|
|
var linkErr *os.LinkError
|
|
if !errors.As(err, &linkErr) || !errors.Is(err, syscall.EXDEV) {
|
|
return fmt.Errorf("renaming %s to %s: %w", src, dst, err)
|
|
}
|
|
|
|
return copyAndRemove(src, dst)
|
|
}
|
|
|
|
// copyAndRemove implements the cross-device fallback: copy src to dst, fsync,
|
|
// then remove src. Uses O_EXCL to belt-and-suspenders against a race.
|
|
func copyAndRemove(src, dst string) error {
|
|
in, err := os.Open(src)
|
|
if err != nil {
|
|
return fmt.Errorf("opening source %s: %w", src, err)
|
|
}
|
|
defer in.Close()
|
|
|
|
out, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0644)
|
|
if err != nil {
|
|
return fmt.Errorf("creating destination %s: %w", dst, err)
|
|
}
|
|
|
|
if _, err := io.Copy(out, in); err != nil {
|
|
out.Close()
|
|
os.Remove(dst)
|
|
return fmt.Errorf("copying %s to %s: %w", src, dst, err)
|
|
}
|
|
|
|
if err := out.Sync(); err != nil {
|
|
out.Close()
|
|
os.Remove(dst)
|
|
return fmt.Errorf("syncing destination %s: %w", dst, err)
|
|
}
|
|
|
|
if err := out.Close(); err != nil {
|
|
os.Remove(dst)
|
|
return fmt.Errorf("closing destination %s: %w", dst, err)
|
|
}
|
|
|
|
if err := in.Close(); err != nil {
|
|
return fmt.Errorf("closing source %s: %w", src, err)
|
|
}
|
|
|
|
if err := os.Remove(src); err != nil {
|
|
return fmt.Errorf("removing source %s: %w", src, err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func MoveToFailed(input, failedDir string) error {
|
|
if err := os.MkdirAll(failedDir, 0755); err != nil {
|
|
return fmt.Errorf("creating failed dir: %w", err)
|
|
}
|
|
dest := filepath.Join(failedDir, filepath.Base(input))
|
|
return safeRename(input, dest)
|
|
}
|
|
|
|
func MoveToOriginals(input, originalsDir string) error {
|
|
if err := os.MkdirAll(originalsDir, 0755); err != nil {
|
|
return fmt.Errorf("creating originals dir: %w", err)
|
|
}
|
|
dest := filepath.Join(originalsDir, filepath.Base(input))
|
|
return safeRename(input, dest)
|
|
}
|
|
|
|
func Delete(path string) error {
|
|
return os.Remove(path)
|
|
}
|
|
|
|
func Rename(source, dest string) error {
|
|
return safeRename(source, dest)
|
|
}
|