Packages a widely-used compression library, enabling direct API access and Okio integration for common use-cases without extra dependencies, focusing on data stream compression and decompression.
The Zstandard compression library (zstd), packaged for Kotlin multiplatform (kmp).
This is intended to be a small library that supports common Zstandard use-cases with zero additional dependencies. For more advanced features, consider using zstd directly.
This library is packaged as two modules:
zstd-kmp: direct access to Zstandard APIs.zstd-kmp-okio: Okio integration.In gradle/libs.versions.toml:
[libraries]
okio-core = { module = "com.squareup.okio:okio", version = "3.15.0" }
zstd-kmp-okio = { module = "com.squareup.zstd:zstd-kmp-okio", version = "0.4.0" }
In build.gradle.kts:
kotlin {
// ...
sourceSets {
val commonMain by getting {
dependencies {
implementation(libs.okio.core)
implementation(libs.zstd.kmp.okio)
}
}
}
}
Turn a Sink into a zstd-compressing sink with zstdCompress(). All data written to that sink will
be compressed and forwarded on. Use buffer() to enable buffering for better performance and a more
capable API.
Use flush() to force all data to be emitted immediately.
Be sure to call close() when you're done, both to emit the last frame and to release the native
resources held by the zstd context. This example uses use() to call close() even if something
throws an exception.
fun compressOneFile(fileSystem: FileSystem, path: Path) {
val zstdPath = "$path.zst".toPath()
fileSystem.source(path).use { fileSource ->
fileSystem.sink(zstdPath).zstdCompress().buffer().use { zstdSink ->
zstdSink.writeAll(fileSource)
}
}
}
Turn a Source of zstd-compressed data into its original form with zstdDecompress().
Don't forget to close this source to release resources held by the zstd context. This example also
uses use() to call close().
fun decompressOneFile(fileSystem: FileSystem, path: Path) {
require(path.name.endsWith(".zst")) { "unexpected path: $path"}
val filePath = path.toString().removeSuffix(".zst").toPath()
fileSystem.source(path).zstdDecompress().use { zstdSource ->
fileSystem.sink(filePath).buffer().use { fileSink ->
fileSink.writeAll(zstdSource)
}
}
}
git submodule init
git submodule update
pushd zstd-kmp
zig build --verbose -p src/jvmMain/resources/jni
popd
./gradlew \
zstd-kmp:jvmTest \
zstd-kmp-okio:jvmTest \
zstd-kmp:macosArm64Test \
zstd-kmp-okio:macosArm64Test
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Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance the License.
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