diff options
Diffstat (limited to 'tx.go')
| -rw-r--r-- | tx.go | 27 |
1 files changed, 16 insertions, 11 deletions
@@ -252,37 +252,42 @@ func (tx *Tx) close() { } // Copy writes the entire database to a writer. -// A reader transaction is maintained during the copy so it is safe to continue -// using the database while a copy is in progress. -// Copy will write exactly tx.Size() bytes into the writer. +// This function exists for backwards compatibility. Use WriteTo() in func (tx *Tx) Copy(w io.Writer) error { - var f *os.File - var err error + _, err := tx.WriteTo(w) + return err +} +// WriteTo writes the entire database to a writer. +// If err == nil then exactly tx.Size() bytes will be written into the writer. +func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) { // Attempt to open reader directly. + var f *os.File if f, err = os.OpenFile(tx.db.path, os.O_RDONLY|odirect, 0); err != nil { // Fallback to a regular open if that doesn't work. if f, err = os.OpenFile(tx.db.path, os.O_RDONLY, 0); err != nil { - return err + return 0, err } } // Copy the meta pages. tx.db.metalock.Lock() - _, err = io.CopyN(w, f, int64(tx.db.pageSize*2)) + n, err = io.CopyN(w, f, int64(tx.db.pageSize*2)) tx.db.metalock.Unlock() if err != nil { _ = f.Close() - return fmt.Errorf("meta copy: %s", err) + return n, fmt.Errorf("meta copy: %s", err) } // Copy data pages. - if _, err := io.CopyN(w, f, tx.Size()-int64(tx.db.pageSize*2)); err != nil { + wn, err := io.CopyN(w, f, tx.Size()-int64(tx.db.pageSize*2)) + n += wn + if err != nil { _ = f.Close() - return err + return n, err } - return f.Close() + return n, f.Close() } // CopyFile copies the entire database to file at the given path. |