40 lines
636 B
Go
40 lines
636 B
Go
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package internal
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import (
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"encoding/binary"
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"errors"
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"io"
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)
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var (
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ErrInvalidMagic = errors.New("Invalid magic")
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sizeEncoding = binary.BigEndian
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magicText = []byte("ENDSLEY/BSDIFF43")
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)
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func WriteHeader(w io.Writer, size uint64) (err error) {
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if _, err = w.Write(magicText); err != nil {
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return
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}
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err = binary.Write(w, sizeEncoding, size)
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return
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}
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func ReadHeader(r io.Reader) (size uint64, err error) {
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magicBuf := make([]byte, len(magicText))
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n, err := r.Read(magicBuf)
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if err != nil {
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return
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}
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if n < len(magicText) {
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err = ErrInvalidMagic
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return
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}
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err = binary.Read(r, sizeEncoding, &size)
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return
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}
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