71 lines
1.3 KiB
Go
71 lines
1.3 KiB
Go
// Package trash provides simple readers with meaningless output.
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package trash
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import (
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"io"
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"math/rand"
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"time"
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)
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func init() {
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Reader = &reader{0xca}
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Zeros = &reader{0x00}
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Fs = &reader{0xff}
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HiLo = &reader{0xaa}
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LoHi = &reader{0x55}
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Random = rand.New(rand.NewSource(time.Now().UnixNano()))
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}
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// Reader provides a steady stream of trash (non-random bytes) when read from
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var Reader io.Reader
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// Zeros provides a steady stream of 0x00
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var Zeros io.Reader
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// Fs provides a steady stream of 0xff
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var Fs io.Reader
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// HiLo provides a steady stream of 0xaa
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var HiLo io.Reader
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// LoHi provides a steady stream of 0x55
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var LoHi io.Reader
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var Random io.Reader
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// TimeoutReader returns a reader that returns io.EOF after dur.
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func TimeoutReader(dur time.Duration) io.Reader {
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return &timeoutReader{timeout: time.Now().Add(dur)}
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}
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type reader struct {
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pattern byte
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}
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func (r *reader) Read(p []byte) (int, error) {
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c := 0
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var err error
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for i := 0; i < len(p); i++ {
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c++
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p[i] = r.pattern
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}
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return c, err
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}
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type timeoutReader struct {
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timeout time.Time
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}
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func (tor *timeoutReader) Read(p []byte) (int, error) {
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c := 0
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var err error
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for i := 0; i < len(p); i++ {
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c++
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p[i] = 0xca
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}
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if time.Now().After(tor.timeout) {
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err = io.EOF
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}
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return c, err
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}
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