49 lines
856 B
Go
49 lines
856 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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changes []change
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}
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type change struct {
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set bool
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index uint64
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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 nil, xerrors.Errorf("could not create RLE+ for a buffer: %w", ErrWrongVersion)
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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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return DecodeRLE(rle.buf)
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}
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func (rle *RLE) Set(index uint64) {
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rle.changes = append(rle.changes, change{set: true, index: index})
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}
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func (rle *RLE) Clear(index uint64) {
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rle.changes = append(rle.changes, change{set: false, index: index})
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}
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