47 lines
750 B
Go
47 lines
750 B
Go
package rand
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import (
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crand "crypto/rand"
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"encoding/binary"
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mrand "math/rand"
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)
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type cryptoSource struct{}
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// Read is alias for crypto/rand.Read.
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var Read = crand.Read
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// New constructs the source of random numbers.
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func New() *mrand.Rand {
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return mrand.New(&cryptoSource{})
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}
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func (s *cryptoSource) Seed(int64) {}
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func (s *cryptoSource) Int63() int64 {
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return int64(s.Uint63())
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}
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func (s *cryptoSource) Uint63() uint64 {
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buf := make([]byte, 8)
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if _, err := crand.Read(buf); err != nil {
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return 0
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}
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return binary.BigEndian.Uint64(buf)
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}
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// Uint64 returns a random uint64 value.
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func Uint64(r *mrand.Rand, max int64) uint64 {
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if max <= 0 {
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return 0
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}
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var i int64 = -1
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for i < 0 {
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i = r.Int63n(max)
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}
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return uint64(i)
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}
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