private int getWrotePosition(final byte[] data) {
        return Bits.getInt(data, SegmentFile.RECORD_MAGIC_BYTES_SIZE + 2 + 8);
    }
Retrieve the log wrote position from metadata.

@param data the metadata
@return the log wrote position
jraft-core/src/main/java/com/alipay/sofa/jraft/storage/log/RocksDBSegmentLogStorage.java