39 lines
742 B
Go
39 lines
742 B
Go
package continuity
|
|
|
|
import (
|
|
"io"
|
|
"io/ioutil"
|
|
"os"
|
|
"path/filepath"
|
|
)
|
|
|
|
// atomicWriteFile writes data to a file by first writing to a temp
|
|
// file and calling rename.
|
|
func atomicWriteFile(filename string, r io.Reader, rf RegularFile) error {
|
|
f, err := ioutil.TempFile(filepath.Dir(filename), ".tmp-"+filepath.Base(filename))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
err = os.Chmod(f.Name(), rf.Mode())
|
|
if err != nil {
|
|
f.Close()
|
|
return err
|
|
}
|
|
n, err := io.Copy(f, r)
|
|
if err == nil && n < rf.Size() {
|
|
f.Close()
|
|
return io.ErrShortWrite
|
|
}
|
|
if err != nil {
|
|
f.Close()
|
|
return err
|
|
}
|
|
if err := f.Sync(); err != nil {
|
|
f.Close()
|
|
return err
|
|
}
|
|
if err := f.Close(); err != nil {
|
|
return err
|
|
}
|
|
return os.Rename(f.Name(), filename)
|
|
}
|