Rewrite Base64/Base64Url helpers without unsafe code

[EgorBo]

Just an AI attempt to rewrite base64 to 100% safe code.

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[EgorBo]

@EgorBot -linux_amd -linux_intel -osx_arm64

using System.Buffers.Text;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench {
    private byte[] _data = default!, _utf8 = default!;

    [Params(16, 32, 64, 150, 256, 1500, 4096, 16384, 65536)]
    public int Size { get; set; }

    [GlobalSetup]
    public void Setup() {
        _data = new byte[Size];
        new Random(42).NextBytes(_data);
        _utf8 = new byte[Base64.GetEncodedLength(Size)];
    }

    [Benchmark] public int B64_EncodeToUtf8() => Base64.EncodeToUtf8(_data, _utf8);
    [Benchmark] public int Url_EncodeToUtf8() => Base64Url.EncodeToUtf8(_data, _utf8);
    [Benchmark] public string Convert_ToBase64String() => Convert.ToBase64String(_data);
    [Benchmark] public string Url_EncodeToString() => Base64Url.EncodeToString(_data);
}

Note

This benchmark was generated with Copilot.

[EgorBo]

@EgorBot -linux_amd -linux_intel -osx_arm64

using System.Buffers.Text;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench {
    private byte[] _b64 = default!, _url = default!, _dest = default!;
    private string _b64String = default!, _urlString = default!;

    [Params(16, 32, 64, 150, 256, 1500, 4096, 16384, 65536)]
    public int Size { get; set; }

    [GlobalSetup]
    public void Setup() {
        byte[] data = new byte[Size];
        new Random(42).NextBytes(data);
        _b64String = Convert.ToBase64String(data);
        _b64 = System.Text.Encoding.ASCII.GetBytes(_b64String);
        _urlString = Base64Url.EncodeToString(data);
        _url = Base64Url.EncodeToUtf8(data);
        _dest = new byte[Size];
    }

    [Benchmark] public int B64_DecodeFromUtf8() => Base64.DecodeFromUtf8(_b64, _dest);
    [Benchmark] public int Url_DecodeFromUtf8() => Base64Url.DecodeFromUtf8(_url, _dest);
    [Benchmark] public byte[] Convert_FromBase64String() => Convert.FromBase64String(_b64String);
    [Benchmark] public int Url_DecodeFromChars() => Base64Url.DecodeFromChars(_urlString, _dest);
}

Note

This benchmark was generated with Copilot.

[EgorBo]

@EgorBot -linux_amd -linux_intel -osx_arm64

using System.Buffers.Text;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench {
    private byte[] _data = default!, _b64 = default!, _url = default!, _buffer = default!;

    [Params(16, 32, 64, 150, 256, 1500, 4096, 16384, 65536)]
    public int Size { get; set; }

    [GlobalSetup]
    public void Setup() {
        _data = new byte[Size];
        new Random(42).NextBytes(_data);
        _b64 = System.Text.Encoding.ASCII.GetBytes(Convert.ToBase64String(_data));
        _url = Base64Url.EncodeToUtf8(_data);
        _buffer = new byte[Base64.GetEncodedLength(Size)];
    }

    [Benchmark]
    public int B64_EncodeInPlace() {
        _data.CopyTo(_buffer, 0);
        Base64.EncodeToUtf8InPlace(_buffer, _data.Length, out int written);
        return written;
    }

    [Benchmark]
    public int Url_EncodeInPlace() {
        _data.CopyTo(_buffer, 0);
        Base64Url.TryEncodeToUtf8InPlace(_buffer, _data.Length, out int written);
        return written;
    }

    [Benchmark]
    public int B64_DecodeInPlace() {
        _b64.CopyTo(_buffer, 0);
        Base64.DecodeFromUtf8InPlace(_buffer.AsSpan(0, _b64.Length), out int written);
        return written;
    }

    [Benchmark]
    public int Url_DecodeInPlace() {
        _url.CopyTo(_buffer, 0);
        return Base64Url.DecodeFromUtf8InPlace(_buffer.AsSpan(0, _url.Length));
    }
}

Note

This benchmark was generated with Copilot.

[EgorBo]

@EgorBot -linux_amd -linux_intel -osx_arm64

using System.Buffers.Text;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench {
    private byte[] _data = default!, _utf8 = default!;

    [Params(16, 32, 64, 150, 256, 1500, 4096, 16384, 65536)]
    public int Size { get; set; }

    [GlobalSetup]
    public void Setup() {
        _data = new byte[Size];
        new Random(42).NextBytes(_data);
        _utf8 = new byte[Base64.GetEncodedLength(Size)];
    }

    [Benchmark] public int B64_EncodeToUtf8() => Base64.EncodeToUtf8(_data, _utf8);
    [Benchmark] public int Url_EncodeToUtf8() => Base64Url.EncodeToUtf8(_data, _utf8);
    [Benchmark] public string Convert_ToBase64String() => Convert.ToBase64String(_data);
    [Benchmark] public string Url_EncodeToString() => Base64Url.EncodeToString(_data);
}

[EgorBo]

@EgorBot -linux_amd -linux_intel -osx_arm64

using System.Buffers.Text;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench {
    private byte[] _b64 = default!, _url = default!, _dest = default!;
    private string _b64String = default!, _urlString = default!;

    [Params(16, 32, 64, 150, 256, 1500, 4096, 16384, 65536)]
    public int Size { get; set; }

    [GlobalSetup]
    public void Setup() {
        byte[] data = new byte[Size];
        new Random(42).NextBytes(data);
        _b64String = Convert.ToBase64String(data);
        _b64 = System.Text.Encoding.ASCII.GetBytes(_b64String);
        _urlString = Base64Url.EncodeToString(data);
        _url = Base64Url.EncodeToUtf8(data);
        _dest = new byte[Size];
    }

    [Benchmark] public int B64_DecodeFromUtf8() => Base64.DecodeFromUtf8(_b64, _dest);
    [Benchmark] public int Url_DecodeFromUtf8() => Base64Url.DecodeFromUtf8(_url, _dest);
    [Benchmark] public byte[] Convert_FromBase64String() => Convert.FromBase64String(_b64String);
    [Benchmark] public int Url_DecodeFromChars() => Base64Url.DecodeFromChars(_urlString, _dest);
}

Note

This benchmark was generated with Copilot.