Method SubmitTargetData

syncer.go:181–223

SubmitTargetData takes received blocks of target data and uses them to fill in missing chunks of the target file. Public for advanced use only: most callers should use FetchRemainingBlocks instead and let the Syncer fetch and submit the blocks. This is provided for callers that want to handle data d

(offset int64, in io.Reader)

// callers that want to handle data downloading via another protocol or
// approach feed the syncer themselves.
func (zs *Syncer) SubmitTargetData(offset int64, in io.Reader) (int64, error) {
	bytesReceived := int64(0)

	if offset%zs.blocksize != 0 {
		panic(fmt.Sprintf("misaligned data block passed as target data (%d, blocksize %d)", offset, zs.blocksize))
	}
	id := rcksum.BlockID(offset / zs.blocksize)

	buf := make([]byte, zs.blocksize)
	var n int
	var err error
	for {
		n, err = io.ReadFull(in, buf)
		if err != nil {
			break
		}
		bytesReceived += int64(n)
		// err == nil implies a full buffer.
		err = zs.rs.SubmitBlocks(buf, id, id)
		if err != nil {
			return bytesReceived, err
		}
		id++
	}
	switch err {
	case io.EOF:
		return bytesReceived, nil
	case io.ErrUnexpectedEOF:
		if id == rcksum.BlockID(zs.blocks-1) {
			// Short last block. rcksum expects a full block, padded with 0s, so pad and submit.
			for i := range buf {
				if i >= n {
					buf[i] = 0
				}
			}
			err = zs.rs.SubmitBlocks(buf, id, id)
			return bytesReceived, err
		} // else fall through; any other incomplete block is an error.
	default:
		// Any other error is returned as-is
	}
	return bytesReceived, err
}

// NewSeedSink returns a io.ReaderFrom that can be used to stream local seed
// local seed data to the Syncer. progressCallback, if provided, will be