30 lines
490 B
Go
30 lines
490 B
Go
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package readers
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import "io"
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// NewPatternReader creates a reader, that returns a deterministic byte pattern.
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// After length bytes are read
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func NewPatternReader(length int64) io.Reader {
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return &patternReader{
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length: length,
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}
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}
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type patternReader struct {
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length int64
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c byte
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}
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func (r *patternReader) Read(p []byte) (n int, err error) {
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for i := range p {
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if r.length <= 0 {
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return n, io.EOF
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}
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p[i] = r.c
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r.c = (r.c + 1) % 253
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r.length--
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n++
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}
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return
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}
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