Introduces TryGetDataLength in addition to GetDataLen.

[ycrumeyrolle]

This method will not throw exception.
This is simplifying the flow, specificialy with the DecodeImpl that will catch the exception then return InvalidData value.

Base64/source/gfoidl.Base64/Internal/Base64UrlEncoder/Base64UrlEncoder.Decode.cs

Lines 105 to 114 in ea95dda

	try
	{
	return this.DecodeImpl(ref src, srcLength, data, decodedLength, out consumed, out written, isFinalBlock);
	}
	catch (FormatException)
	{
	consumed = 0;
	written = 0;
	return OperationStatus.InvalidData;
	}

The same pattern may also be replaced at

Base64/source/gfoidl.Base64/Internal/Base64UrlEncoder/Base64UrlEncoder.Decode.cs

Lines 16 to 29 in a347ced

	public override int GetMaxDecodedLength(int encodedLength)
	{
	try
	{
	return this.GetDecodedLength(encodedLength);
	}
	catch (FormatException)
	{
	// In the case of malformed input, i.e. wrong number of padding,
	// just assume 2 padding chars and compute the data length.
	// It's "max" anyway.
	return (encodedLength + 2) / 4 * 3;
	}
	}

Benchmarks

No benchmark for the moment...

[gfoidl]

Nice! 👍
This should improve perf, as there's no try-catch-block. I'm going to merge this, and try to tweak it a bit more in a follow-up pr.

Thank you!