public void BasicEncodingDecoding()
{
var bytes = new byte[byte.MaxValue + 1];
for (int i = 0; i < byte.MaxValue + 1; i++)
{
bytes[i] = (byte)i;
}
for (int value = 0; value < 256; value++)
{
Span <byte> sourceBytes = bytes.AsSpan().Slice(0, value + 1);
Span <byte> encodedBytes = new byte[Base64Encoder.ComputeEncodedLength(sourceBytes.Length)];
Assert.True(Base64Encoder.TryEncode(sourceBytes, encodedBytes, out int consumed, out int encodedBytesCount));
Assert.Equal(encodedBytes.Length, encodedBytesCount);
string encodedText = Text.Encoding.ASCII.GetString(encodedBytes.ToArray());
string expectedText = Convert.ToBase64String(bytes, 0, value + 1);
Assert.Equal(expectedText, encodedText);
if (encodedBytes.Length % 4 == 0)
{
Span <byte> decodedBytes = new byte[Base64Encoder.ComputeDecodedLength(encodedBytes)];
Assert.True(Base64Encoder.TryDecode(encodedBytes, decodedBytes, out consumed, out int decodedByteCount));
Assert.Equal(sourceBytes.Length, decodedByteCount);
Assert.True(sourceBytes.SequenceEqual(decodedBytes));
}
}
}
public void DecodeInPlace()
{
var list = new List <byte>();
for (int value = 0; value < 256; value++)
{
list.Add((byte)value);
}
var testBytes = list.ToArray();
for (int value = 0; value < 256; value++)
{
var sourceBytes = testBytes.AsSpan().Slice(0, value + 1);
var buffer = new byte[Base64Encoder.ComputeEncodedLength(sourceBytes.Length)];
var bufferSlice = buffer.AsSpan();
Base64Encoder.TryEncode(sourceBytes, bufferSlice, out int consumed, out int written);
var encodedText = Text.Encoding.ASCII.GetString(bufferSlice.ToArray());
var expectedText = Convert.ToBase64String(testBytes, 0, value + 1);
Assert.Equal(expectedText, encodedText);
var decodedByteCount = Base64Encoder.DecodeInPlace(bufferSlice);
Assert.Equal(sourceBytes.Length, decodedByteCount);
for (int i = 0; i < decodedByteCount; i++)
{
Assert.Equal(sourceBytes[i], buffer[i]);
}
}
}
public void ComputeEncodedLength()
{
// (int.MaxValue - 4)/(4/3) => 1610612733, otherwise integer overflow
int[] input = { 0, 1, 2, 3, 4, 5, 6, 1610612728, 1610612729, 1610612730, 1610612731, 1610612732, 1610612733 };
int[] expected = { 0, 4, 4, 4, 8, 8, 8, 2147483640, 2147483640, 2147483640, 2147483644, 2147483644, 2147483644 };
for (int i = 0; i < input.Length; i++)
{
Assert.Equal(expected[i], Base64Encoder.ComputeEncodedLength(input[i]));
}
Assert.True(Base64Encoder.ComputeEncodedLength(1610612734) < 0); // integer overflow
}
private static void Base64EncodeBaseline(int numberOfBytes)
{
var source = new byte[numberOfBytes];
InitalizeBytes(source.AsSpan());
var destination = new char[Base64Encoder.ComputeEncodedLength(numberOfBytes)];
foreach (var iteration in Benchmark.Iterations)
{
using (iteration.StartMeasurement()) {
for (int i = 0; i < Benchmark.InnerIterationCount; i++)
{
Convert.ToBase64CharArray(source, 0, source.Length, destination, 0);
}
}
}
}
private static void Base64Encode(int numberOfBytes)
{
Span <byte> source = new byte[numberOfBytes];
InitalizeBytes(source);
Span <byte> destination = new byte[Base64Encoder.ComputeEncodedLength(numberOfBytes)];
foreach (var iteration in Benchmark.Iterations)
{
using (iteration.StartMeasurement()) {
for (int i = 0; i < Benchmark.InnerIterationCount; i++)
{
Base64Encoder.TryEncode(source, destination, out int consumed, out int written);
}
}
}
}
public void BasicEncoding()
{
var rnd = new Random(42);
for (int i = 0; i < 10; i++)
{
int numBytes = rnd.Next(100, 1000 * 1000);
Span <byte> source = new byte[numBytes];
InitalizeBytes(source, numBytes);
Span <byte> encodedBytes = new byte[Base64Encoder.ComputeEncodedLength(source.Length)];
Assert.True(Base64Encoder.TryEncode(source, encodedBytes, out int consumed, out int encodedBytesCount));
Assert.Equal(encodedBytes.Length, encodedBytesCount);
string encodedText = Text.Encoding.ASCII.GetString(encodedBytes.ToArray());
string expectedText = Convert.ToBase64String(source.ToArray());
Assert.Equal(expectedText, encodedText);
}
}
public void EncodingOutputTooSmall()
{
Span <byte> source = new byte[750];
InitalizeBytes(source);
int outputSize = 320;
int requiredSize = Base64Encoder.ComputeEncodedLength(source.Length);
Span <byte> encodedBytes = new byte[outputSize];
Assert.False(Base64Encoder.TryEncode(source, encodedBytes, out int consumed, out int written));
Assert.Equal(encodedBytes.Length, written);
Assert.Equal(encodedBytes.Length / 4 * 3, consumed);
encodedBytes = new byte[requiredSize - outputSize];
Assert.True(Base64Encoder.TryEncode(source.Slice(consumed), encodedBytes, out consumed, out written));
Assert.Equal(encodedBytes.Length, written);
Assert.Equal(encodedBytes.Length / 4 * 3, consumed);
string encodedText = Text.Encoding.ASCII.GetString(encodedBytes.ToArray());
string expectedText = Convert.ToBase64String(source.ToArray()).Substring(outputSize);
Assert.Equal(expectedText, encodedText);
}