Imgur-esque hash generator written in Go

main.go

package main

import (
	"crypto/rand"
	"fmt"
	"log"
)

func main() {
	hashGetter := make(chan string)
	length := 7

	go func() {
		for {
			str := ""

			for len(str) < length {
				c := 10
				bArr := make([]byte, c)
				_, err := rand.Read(bArr)
				if err != nil {
					log.Println("error:", err)
					break
				}

				for _, b := range bArr {
					if len(str) == length {
						break
					}

					/**
					 * Each byte will be in [0, 256), but we only care about:
					 *
					 * [48, 57]     0-9
					 * [65, 90]     A-Z
					 * [97, 122]    a-z
					 *
					 * Which means that the highest bit will always be zero, since the last byte with high bit
					 * zero is 01111111 = 127 which is higher than 122. Lower our odds of having to re-roll a byte by
					 * dividing by two (right bit shift of 1).
					 */

					b = b >> 1

					// The byte is any of        0-9                  A-Z                      a-z
					byteIsAllowable := (b >= 48 && b <= 57) || (b >= 65 && b <= 90) || (b >= 97 && b <= 122)

					if byteIsAllowable {
						str += string(b)
					}
				}

			}

			hashGetter <- str
		}
	}()

	for i := 0; i < 5; i++ {
		fmt.Println(<-hashGetter)
	}
}