Gapotchenko.FX.Data.Integrity.Checksum 2022.1.4

Overview

The module provides a quasi-universal framework for cyclic redundancy checks. It supports both synchronous and asynchronous data processing, including the iterative checksum computation.

IChecksumAlgorithm<T>

This is the root interface provided by a checksum algorithm. The generic parameter T defines the data type of a checksum value. For example, System.UInt32 would be a type T for a CRC-32 algorithm.

Checksum algorithm interface provides several notable methods.

ComputeChecksum(ReadOnlySpan<byte> data)

The method allows to compute a checksum value for the specified byte span. This is the most widely used operation. Example:

var data = new byte[] { ... };
var checksum = checksumAlgorithm.ComputeChecksum(data);
Console.WriteLine("The array checksum is {0}.", checksum);

ComputeChecksum(Stream stream)

The method computes the checksum for the specified System.IO.Stream object. This operation is useful for computing a checksum for a file or any other data stream in one go. Example:

using var file = File.OpenRead(...);
var checksum = checksumAlgorithm.ComputeChecksum(file);
Console.WriteLine("The file checksum is {0}.", checksum);

CreateIterator()

Sometimes the checksum computation cannot be performed in one go, and should be performed in chunks. That's why every checksum algorithm provides CreateIterator() method.

Once the iterator is created, it can be used for iterative checksum computation without data concatenation overhead:

var iterator = checksumAlgorithm.CreateIterator();

iterator.ComputeBlock(...); // block 1
// ...
iterator.ComputeBlock(...); // block N
// ...

// Compute the final checksum value:
var checksum = iterator.ComputeFinal();

Console.WriteLine("The checksum is {0}.", checksum);

Checksum Algorithms

Gapotchenko.FX.Data.Integrity.Checksum module provides only a framework for checksum algorithms. If you want to use a popular and ready-to-use checksum algorithm, Gapotchenko.FX provides quite a few out of the box:

Moreover, you can create your own checksum algorithm. Gapotchenko.FX project welcomes contributions, or it can be a standalone NuGet package that uses Gapotchenko.FX.Data.Integrity.Checksum module as a wireframe.