Buckets.max truncation in buckets.go

[mattlorimor]

Buckets.max can never be larger than 255 even though the math allows for larger numbers. This is because the type of Buckets.max is set to uint8. Obviously, if this behavior is intended, feel free to close this.

The math for setting Buckets.max is:

(1 << bucketSize) -1

where bucketSize is a uint8.

(1 << bucketSize) - 1 will have these outputs given a uint8:

for i := 0; i < 255; i++ {
        fmt.Println(uint64((1 << uint8(i)) - 1))
    }

input	output
0	0
1	1
2	3
3	7
4	15
5	31
6	63
7	127
8	255
...	...
62	4611686018427387903
63	9223372036854775807
64	18446744073709551615

Anything past 64 would overflow a uint64.

I'm not sure what the best solution would be (or even if Buckets.max allowing nothing larger than 255 is even a problem). Should Buckets.max be changed to a uint? A uint64? I'm not that familiar with what maximum, if any, should be enforced on Buckets.max.

[tylertreat]

It can probably be a uint32 or uint64, but bucketSize should be capped to prevent an overflow.