Method CacheFullAndWriter

internal/stream/stream.go:65–165

CacheFullAndWriter save all data into tmpFile or memory. It's not thread-safe!

(up *model.UpdateProgress, writer io.Writer)

// CacheFullAndWriter save all data into tmpFile or memory.
// It's not thread-safe!
func (f *FileStream) CacheFullAndWriter(up *model.UpdateProgress, writer io.Writer) (model.File, error) {
	if cache := f.GetFile(); cache != nil {
		_, err := cache.Seek(0, io.SeekStart)
		if err != nil {
			return nil, err
		}
		if writer == nil {
			return cache, nil
		}
		reader := f.Reader
		if up != nil {
			cacheProgress := model.UpdateProgressWithRange(*up, 0, 50)
			*up = model.UpdateProgressWithRange(*up, 50, 100)
			reader = &ReaderUpdatingProgress{
				Reader: &SimpleReaderWithSize{
					Reader: reader,
					Size:   f.GetSize(),
				},
				UpdateProgress: cacheProgress,
			}
		}
		_, err = utils.CopyWithBuffer(writer, reader)
		if err == nil {
			_, err = cache.Seek(0, io.SeekStart)
		}
		if err != nil {
			return nil, err
		}
		return cache, nil
	}

	reader := f.Reader
	if f.peek != nil {
		f.peek.Seek(0, io.SeekStart)
		if writer != nil {
			_, err := utils.CopyWithBuffer(writer, f.peek)
			if err != nil {
				return nil, err
			}
			f.peek.Seek(0, io.SeekStart)
		}
		reader = f.oriReader
	}
	if writer != nil {
		reader = io.TeeReader(reader, writer)
	}

	// 如果文件大小未知，直接缓存到磁盘
	if f.GetSize() < 0 {
		// 检查是否有数据
		buf := []byte{0}
		n, err := io.ReadFull(reader, buf)
		br := bytes.NewReader(buf[:n])
		if err == io.ErrUnexpectedEOF || err == io.EOF {
			f.size = br.Size()
			f.Reader = br
			return br, nil
		} else if err != nil {