/// <summary>
/// Generates a random long value.
/// </summary>
/// <param name="minValue">The inclusive lower bound of the random number returned.</param>
/// <param name="maxValue">The inclusive upper bound of the random number returned.</param>
/// <returns>A long value generated randomly.</returns>
public long GenerateLong(long?minValue = null, long?maxValue = null)
{
minValue = minValue ?? long.MinValue;
maxValue = maxValue ?? long.MaxValue;
if (maxValue.Value <= minValue.Value)
{
throw new ArgumentOutOfRangeException("maxValue", "maxValue must be > minValue!");
}
//Working with ulong so that modulo works correctly with values > long.MaxValue
var uRange = NumberExtensions.ComputeRange(minValue, maxValue);
//Prevent a modolo bias; see https://stackoverflow.com/a/10984975/238419
//for more information.
//In the worst case, the expected number of calls is 2 (though usually it's
//much closer to 1) so this loop doesn't really hurt performance at all.
ulong ulongRand;
var maxValue1 = ulong.MaxValue - ((ulong.MaxValue % uRange) + 1) % uRange;
do
{
var buf = new byte[8];
_fuzzer.Random.NextBytes(buf);
ulongRand = (ulong)BitConverter.ToInt64(buf, 0);
} while (ulongRand > maxValue1);
var modulo = (long)(ulongRand % uRange);
var result = modulo + minValue.Value;
return(result);
}