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Kotlin/Native

stormcat24
October 19, 2017

 Kotlin/Native

2017/10/19 CA.kt #3

stormcat24

October 19, 2017
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  1. Kotlin/Native is ‣Compiles directly to native code via LLVM ‣Call

    native libraries ‣Cross Platform ‣Windows/Linux/macOS/iOS/Android/Raspberry Pi ‣Version 0.3
  2. Setup $ git clone [email protected]:JetBrains/kotlin-native.git $ cd kotlin-native (kotlin-native)$ git

    checkout v0.3.4 Get Kotlin/Native Build (kotlin-native)$ ./gradlew dependencies:update (kotlin-native)$ ./gradlew dist (kotlin-native)$ ./gradlew cross_dist Path $ export PATH=$PATH:path-to-path/kotlin-native/dist/bin
  3. Try Quickly fun main(args: Array<String>) { // Not System.out.println() println(“Hello!

    Kotlin/Native“) } hello.kt compile $ kotlinc hello.kt -o hello KtFile: hello.kt Execute $ ./hello.kexe Hello! Kotlin/Native
  4. build.gradle buildscript { repositories { mavenCentral() maven { url "https://dl.bintray.com/jetbrains/kotlin-native-dependencies"

    } } dependencies { classpath "org.jetbrains.kotlin:kotlin-native-gradle-plugin:0.3.3" } } apply plugin: 'konan' konanArtifacts { KonanExample { } }
  5. Create *.def file ‣Library definition file ‣Link Kotlin/Native to Native

    libraries ‣Generate interoperability stubs ‣Define in build.gradle
  6. Define *.def file headers = curl/curl.h compilerOpts=-I/usr/local/include linkerOpts.osx = -L/opt/local/lib

    -L/usr/local/opt/curl/lib -lcurl src/main/c_interop/libcurl.def build.gradle apply plugin: 'konan' konanInterop { Libcurl { includeDirs '/usr/local/opt/curl/include', '.' } } konanArtifacts { KonanExample { useInterop 'libcurl' } }
  7. Implementation curl.kt import kotlinx.cinterop.* import libcurl.* fun main(args: Array<String>): Unit

    { if (args.size == 0) { return } val url = args.first() val curl = curl_easy_init() curl_easy_setopt(curl, CURLOPT_URL, url) val res = curl_easy_perform(curl) when (res) { CURLE_OK -> println("HTTP Request OK") else -> println("HTTP Request NG") } }
  8. Call Library In C #include <curl/curl.h> CURLcode curl_easy_perform(CURL * easy_handle);

    fun curl_easy_perform(curl: COpaquePointer?): CURLcode { return kniBridge40(curl.rawValue) } typealias CURLcode = kotlin.Int val CURLE_OK: CURLcode = 0 val CURLE_UNSUPPORTED_PROTOCOL: CURLcode = 1 val CURLE_FAILED_INIT: CURLcode = 2 … Stub in Kotlin/Native
  9. Execute Build Execute $ ./gradlew build $ ls build/konan/bin Curl.kexe

    Curl.kt.bc $ build/konan/bin/Curl.kexe https://blog.stormcat.io <!DOCTYPE html> <html lang="ja-jp"> <head> <meta charset="utf-8" /> <meta http-equiv="X-UA-Compatible" content="IE=edge" /> (...) HTTP Request OK
  10. Memory allocation Allocate memory val buffer = nativeHeap.allocArray<ByteVar>(size) ... nativeHeap.free(buffer)

    memScoped val fileSize = memScoped { val statBuf = alloc<statStruct>() val error = stat("/", statBuf.ptr) statBuf.st_size }
  11. Impressions ‣Very experimental and challenging ‣Interoperability is difficult ‣Lack of

    Ecosystem, fundamental libraries ‣Not enough code completion ‣If gRPC support Kotlin/Native?