48 lines
791 B
Go
48 lines
791 B
Go
package rlepluslazy
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import (
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"errors"
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"fmt"
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"golang.org/x/xerrors"
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)
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const Version = 0
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var (
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ErrWrongVersion = errors.New("invalid RLE+ version")
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ErrDecode = fmt.Errorf("invalid encoding for RLE+ version %d", Version)
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)
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type RLE struct {
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buf []byte
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}
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func FromBuf(buf []byte) (RLE, error) {
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rle := RLE{buf: buf}
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if len(buf) > 0 && buf[0]&3 != Version {
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return RLE{}, xerrors.Errorf("could not create RLE+ for a buffer: %w", ErrWrongVersion)
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}
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_, err := rle.Count()
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if err != nil {
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return RLE{}, err
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}
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return rle, nil
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}
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func (rle *RLE) RunIterator() (RunIterator, error) {
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source, err := DecodeRLE(rle.buf)
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return source, err
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}
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func (rle *RLE) Count() (uint64, error) {
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it, err := rle.RunIterator()
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if err != nil {
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return 0, err
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}
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return Count(it)
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}
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