diff options
Diffstat (limited to 'tx.go')
| -rw-r--r-- | tx.go | 32 |
1 files changed, 27 insertions, 5 deletions
@@ -297,12 +297,34 @@ func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) { } defer func() { _ = f.Close() }() - // Copy the meta pages. - tx.db.metalock.Lock() - n, err = io.CopyN(w, f, int64(tx.db.pageSize*2)) - tx.db.metalock.Unlock() + // Generate a meta page. We use the same page data for both meta pages. + buf := make([]byte, tx.db.pageSize) + page := (*page)(unsafe.Pointer(&buf[0])) + page.flags = metaPageFlag + *page.meta() = *tx.meta + + // Write meta 0. + page.id = 0 + page.meta().checksum = page.meta().sum64() + nn, err := w.Write(buf) + n += int64(nn) if err != nil { - return n, fmt.Errorf("meta copy: %s", err) + return n, fmt.Errorf("meta 0 copy: %s", err) + } + + // Write meta 1 with a lower transaction id. + page.id = 1 + page.meta().txid -= 1 + page.meta().checksum = page.meta().sum64() + nn, err = w.Write(buf) + n += int64(nn) + if err != nil { + return n, fmt.Errorf("meta 1 copy: %s", err) + } + + // Move past the meta pages in the file. + if _, err := f.Seek(int64(tx.db.pageSize*2), os.SEEK_SET); err != nil { + return n, fmt.Errorf("seek: %s", err) } // Copy data pages. |