restic/internal/fs/fs_track.go
2024-02-10 22:58:10 +01:00

54 lines
1.3 KiB
Go

package fs
import (
"fmt"
"os"
"runtime"
"runtime/debug"
)
// Track is a wrapper around another file system which installs finalizers
// for open files which call panic() when they are not closed when the garbage
// collector releases them. This can be used to find resource leaks via open
// files.
type Track struct {
FS
}
// Open wraps the Open method of the underlying file system.
func (fs Track) Open(name string) (File, error) {
f, err := fs.FS.Open(fixpath(name))
if err != nil {
return nil, err
}
return newTrackFile(debug.Stack(), name, f), nil
}
// OpenFile wraps the OpenFile method of the underlying file system.
func (fs Track) OpenFile(name string, flag int, perm os.FileMode) (File, error) {
f, err := fs.FS.OpenFile(fixpath(name), flag, perm)
if err != nil {
return nil, err
}
return newTrackFile(debug.Stack(), name, f), nil
}
type trackFile struct {
File
}
func newTrackFile(stack []byte, filename string, file File) *trackFile {
f := &trackFile{file}
runtime.SetFinalizer(f, func(_ *trackFile) {
fmt.Fprintf(os.Stderr, "file %s not closed\n\nStacktrack:\n%s\n", filename, stack)
panic("file " + filename + " not closed")
})
return f
}
func (f *trackFile) Close() error {
runtime.SetFinalizer(f, nil)
return f.File.Close()
}