reader.go 878 B

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  1. package buffer
  2. import "io"
  3. // Reader implements an io.Reader over a byte slice.
  4. type Reader struct {
  5. buf []byte
  6. pos int
  7. }
  8. // NewReader returns a new Reader for a given byte slice.
  9. func NewReader(buf []byte) *Reader {
  10. return &Reader{
  11. buf: buf,
  12. }
  13. }
  14. // Read reads bytes into the given byte slice and returns the number of bytes read and an error if occurred.
  15. func (r *Reader) Read(b []byte) (n int, err error) {
  16. if len(b) == 0 {
  17. return 0, nil
  18. }
  19. if r.pos >= len(r.buf) {
  20. return 0, io.EOF
  21. }
  22. n = copy(b, r.buf[r.pos:])
  23. r.pos += n
  24. return
  25. }
  26. // Bytes returns the underlying byte slice.
  27. func (r *Reader) Bytes() []byte {
  28. return r.buf
  29. }
  30. // Reset resets the position of the read pointer to the beginning of the underlying byte slice.
  31. func (r *Reader) Reset() {
  32. r.pos = 0
  33. }
  34. // Len returns the length of the buffer.
  35. func (r *Reader) Len() int {
  36. return len(r.buf)
  37. }