distribution/vendor/github.com/aws/aws-sdk-go/service/cloudfront/sign/randomreader.go

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package sign
import (
"bytes"
"encoding/binary"
"math/rand"
)
// A randomReader wraps a math/rand.Rand within an reader so that it can used
// as a predictable testing replacement for crypto/rand.Reader
type randomReader struct {
b *bytes.Buffer
r *rand.Rand
}
// newRandomReader returns a new instance of the random reader
func newRandomReader(r *rand.Rand) *randomReader {
return &randomReader{b: &bytes.Buffer{}, r: r}
}
// Read will read random bytes from up to the length of b.
func (m *randomReader) Read(b []byte) (int, error) {
for i := 0; i < len(b); {
binary.Write(m.b, binary.LittleEndian, m.r.Int63())
n, _ := m.b.Read(b[i:])
i += n
}
return len(b), nil
}