33 lines
657 B
Go
33 lines
657 B
Go
// Copyright 2020 the u-root Authors. All rights reserved
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build plan9 || windows
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// +build plan9 windows
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package rand
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import (
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"context"
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"crypto/rand"
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)
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var defaultContextReader = &cryptoRandReader{}
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type cryptoRandReader struct{}
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// ReadContext implements a cancelable read.
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func (r *cryptoRandReader) ReadContext(ctx context.Context, b []byte) (n int, err error) {
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ch := make(chan struct{})
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go func() {
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n, err = rand.Reader.Read(b)
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close(ch)
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}()
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select {
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case <-ctx.Done():
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return 0, ctx.Err()
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case <-ch:
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return n, err
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}
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}
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