37 lines
659 B
Go
37 lines
659 B
Go
package rand
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import (
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"crypto/rand"
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)
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var chars = []byte("abcdefghijklmnopqrstuvwxyz0123456789")
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// random string length
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const length = 32
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// String returns a string value.
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func String() string {
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clen := len(chars)
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maxrb := 255 - (256 % clen)
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b := make([]byte, length)
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r := make([]byte, length+(length/4)) // storage for random bytes.
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i := 0
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for {
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if _, err := rand.Read(r); err != nil {
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panic("rand: error reading random bytes")
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}
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for _, rb := range r {
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c := int(rb)
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if c > maxrb {
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// Skip this number to avoid modulo bias.
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continue
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}
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b[i] = chars[c%clen]
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i++
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if i == length {
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return string(b)
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}
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}
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}
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}
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