Swift Wrapper around Zstandard Compression Library
Zstandard is required to be installed in order to build this package. See https://github.com/facebook/zstd for additional information, including licensing.
On OS X the easiest way to install Zstandard is with homebrew
brew install zstdOn Ubuntu it can be installed with apt
sudo apt install libzstd-devThis has been bundled as a swift package for Swift 5. To use it in a project include the pacakge as a dependency in your projects Package.swift:
dependencies: [
.package(url: "https://github.com/HeartedApp/SwiftZSTD", .branch("master"))
],In order to test out the included example ZSTDSampleApp run swift run
$ swift run
Testing compression
Original size: 1465 bytes
Compressed size: 757 bytes
Decompressed string is the same as original.
Testing compression with dictionary
Building Dictionary
Original size: 1465 bytes
Compressed size: 438 bytes
Dictionary decompressed string is the same as original.Compression and de-compression of in-memory buffers is supported, with or without a context or a dictionary. Buffers are represented by Data instances that must use contiguous storage, and in practice most Data instances meet this requirement. To be decompressed by this code, a buffer must be a complete frame with decompressed size encoded in it and retrievable using ZSTD_getDecompressedSize().
This is actually a fairly useful implementation. Experimentation shows that even fairly large files (100s of MB),when compressed using the zstd utility provided with the C library, end up in a single frame, which is easily decompressible by this Swift code if read into memory as one piece.