package buf import "io" // BytesToBufferReader is a Reader that adjusts its reading speed automatically. type BytesToBufferReader struct { reader io.Reader largeBuffer *Buffer highVolumn bool } // Read implements Reader.Read(). func (v *BytesToBufferReader) Read() (*Buffer, error) { if v.highVolumn && v.largeBuffer.IsEmpty() { if v.largeBuffer == nil { v.largeBuffer = NewLocal(32 * 1024) } err := v.largeBuffer.AppendSupplier(ReadFrom(v.reader)) if err != nil { return nil, err } if v.largeBuffer.Len() < Size { v.highVolumn = false } } buffer := New() if !v.largeBuffer.IsEmpty() { err := buffer.AppendSupplier(ReadFrom(v.largeBuffer)) return buffer, err } err := buffer.AppendSupplier(ReadFrom(v.reader)) if err != nil { buffer.Release() return nil, err } if buffer.IsFull() { v.highVolumn = true } return buffer, nil } type BufferToBytesReader struct { stream Reader current *Buffer err error } // Fill fills in the internal buffer. // Private: Visible for testing. func (v *BufferToBytesReader) Fill() { b, err := v.stream.Read() v.current = b if err != nil { v.err = err v.current = nil } } func (v *BufferToBytesReader) Read(b []byte) (int, error) { if v.err != nil { return 0, v.err } if v.current == nil { v.Fill() if v.err != nil { return 0, v.err } } nBytes, err := v.current.Read(b) if v.current.IsEmpty() { v.current.Release() v.current = nil } return nBytes, err }