Trying to send back a jstring from kotlin native jni-bridge, is there a way to create/convert a kotlin string to a jstring? Example I have now:

@CName("Java_com_example_project_createString")
fun createString(env: kotlinx.cinterop.CPointer<JNIEnvVar>, instance: jobject):jstring?{
    val jniNativeInterface: JNINativeInterface = env.pointed.pointed!!
    val fNewStringUTF = jniNativeInterface.NewStringUTF!!
    val result = fNewStringUTF(env, "A test")
    return result
}

Where the 'A test' part wont work, because of it not being a jstring

Here's a follow-up to the thread about memory-model & my proposal for const classes to reduce multiplatform friction: https://medium.com/@timelzayus/designing-a-kotlin-memory-safe-mode-c76c06317c3e

If you are in swift trying to access a Kotlin/native extension function - what does that look like? i.e. for JVM it’s expressed as a static utility / helper class.

Added some additional definitions in the udev.def file, and encountered a linking error, where it isn't clear what is causing the error:

Task :cinteropUdevLinux FAILED
Exception in thread "main" java.lang.Error: /tmp/tmp360311134357443805.c:26:3: error: expected expression

I'm somewhat confused. I converted a c-function, which ends up being this in kotlin:

public fun AES_CBC_encrypt_buffer(output: kotlinx.cinterop.CValuesRef<platform.posix.uint8_tVar /* = kotlinx.cinterop.UByteVarOf<platform.posix.uint8_t /* = kotlin.UByte */> */>?, input: kotlinx.cinterop.CValuesRef<platform.posix.uint8_tVar /* = kotlinx.cinterop.UByteVarOf<platform.posix.uint8_t /* = kotlin.UByte */> */>?, length: platform.posix.uint32_t /* = kotlin.UInt */, key: kotlinx.cinterop.CValuesRef<platform.posix.uint8_tVar /* = kotlinx.cinterop.UByteVarOf<platform.posix.uint8_t /* = kotlin.UByte */> */>?, iv: kotlinx.cinterop.CValuesRef<platform.posix.uint8_tVar /* = kotlinx.cinterop.UByteVarOf<platform.posix.uint8_t /* = kotlin.UByte */> */>?): kotlin.Unit { /* compiled code */ }

I'm trying to use it with the following setup: https://gist.github.com/Syrou/52db691f91928cb6aad6bcfd84bf5cff 1. Am I wrong in trying to use toCValues() method to translate the uByteArrays into what is specified in the method argument? 2. Am I using the buffer pinning wrong? Because each time I run this code I end up with a new result. This might be an error in the c-lib to start with, but I'm currently investigating if my implementation of the native code is wrong.

With the libusb library the

libusb_get_device_list

function takes a list (parameter) however the list is a container for

libusb_device

, which is a opaque pointer. Is there a way to allocate a opaque pointer? Below is the function's mapping:

public fun libusb_get_device_list(ctx: kotlinx.cinterop.CValuesRef<cnames.structs.libusb_context>?, list: kotlinx.cinterop.CValuesRef<kotlinx.cinterop.CPointerVar<kotlinx.cinterop.CPointerVar<cnames.structs.libusb_device> /* = kotlinx.cinterop.CPointerVarOf<kotlinx.cinterop.CPointer<cnames.structs.libusb_device>> */> /* = kotlinx.cinterop.CPointerVarOf<kotlinx.cinterop.CPointer<kotlinx.cinterop.CPointerVarOf<kotlinx.cinterop.CPointer<cnames.structs.libusb_device>>>> */>?): platform.posix.ssize_t /* = kotlin.Long */ { /* compiled code */ }

Does kotlin-native (iOS) has problems with dashes in pod dependencies? e.g.

cocoapods { ... pod("SignalR-ObjC") }

fails with

> Task :redacted:cinteropSignalR-ObjCIosX64 FAILED

Exception in thread "main" java.lang.Error: /var/folders/5w/vjnd8mf17jlclpg31lfzlk0h0000gn/T/tmp3333782877975402348.m:1:9: fatal error: module 'SignalR' not found

When using a C library (via Kotlin Native) with Kotlin Coroutines would it be better to go with a synchronous API (eg http://libusb.sourceforge.net/api-1.0/group__libusb__syncio.html ), or a asynchronous API (eg http://libusb.sourceforge.net/api-1.0/group__libusb__asyncio.html )?

Is there .toKString() with charset specification? I'm using Mingw, strerror() charset is locale dependent and setlocale() don't allow UTF-8 codepage.

Hello everyone. I need to use a static C library, written by a friend of mine. How do I include it in a Kotlin/Native project, using CInterop? And also, how do I use the library from there in an android client?

Just in case anyone stuck with Gradle task

linkDebugTestLinuxX64

failing with error message

e: Unable to compile C bridges

on Ubuntu: you have to install

libtinfo5

and perhaps

libtinfo-dev

packages. Wasted 1h on this problem 😞

Is there a straightforward way to convert

CArrayPointer<UByteVar>

to a String?

hello everyone , i'm just starting with kotlin native and want to understand how kotlin native concurrency and memory model works, so i need some tutorials or blogs thanks in advance

Could anyone get wasm32 compiling with Kotlin 1.3.50 on Linux? Just getting a JVM crash on

linkDebugExecutableWasm32

. Kotlin 1.3.41 is working fine.

Hey folks, is there a way to interop with a cocoapods swift dependency from kotlin/native in a multiplatform project?

Hi everyone, I want to generate .so file for Android, only androidNativeArm64 / 32, how to generate x86 / x86_64 for android? Can i use linux???

Just updating from 1.3.41 to 1.3.50, something broke:

> Task :...:bugsnag:cinteropBugsnagIos
Exception in thread "main" java.lang.IllegalStateException: clang_parseTranslationUnit2 failed with CXError_ASTReadError;
sourceFile = /var/folders/6l/fxc2038542q1pfrjs6br35pw0000gn/T/tmp447253035168640890tmp5260654680929876680.m
arguments = -framework Bugsnag -fmodules -isystem /Users/me/.konan/dependencies/clang-llvm-6.0.1-darwin-macos/lib/clang/6.0.1/include -B/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin -fno-stack-protector -stdlib=libc++ -arch arm64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.4.sdk -miphoneos-version-min=9.0.0 -I/Users/me/IdeaProjects/.../bugsnag/Carthage/Build/iOS/Bugsnag.framework/Headers -fobjc-arc -include-pch /var/folders/6l/fxc2038542q1pfrjs6br35pw0000gn/T/tmp1938929871985065456.pch -Werror=implicit-function-declaration -ferror-limit=0
	at org.jetbrains.kotlin.native.interop.indexer.UtilsKt.parseTranslationUnit(Utils.kt:99)
	at org.jetbrains.kotlin.native.interop.indexer.MacroConstantsKt.expandMacros(MacroConstants.kt:66)
	at org.jetbrains.kotlin.native.interop.indexer.MacroConstantsKt.findMacros(MacroConstants.kt:34)
	at org.jetbrains.kotlin.native.interop.indexer.IndexerKt.indexDeclarations(Indexer.kt:999)
	at org.jetbrains.kotlin.native.interop.indexer.IndexerKt.buildNativeIndexImpl(Indexer.kt:952)
	at org.jetbrains.kotlin.native.interop.indexer.NativeIndexKt.buildNativeIndex(NativeIndex.kt:91)
	at org.jetbrains.kotlin.native.interop.gen.jvm.MainKt.processCLib(main.kt:222)
	at org.jetbrains.kotlin.native.interop.gen.jvm.MainKt.interop(main.kt:38)
	at org.jetbrains.kotlin.cli.utilities.InteropCompilerKt.invokeInterop(InteropCompiler.kt:69)
	at org.jetbrains.kotlin.cli.utilities.MainKt.main(main.kt:18)

hey there, I have 2 mpp modules A and B. B is using A as a dependency. I produced FAT frameworks from both of them, and include both framework in my iOS app. Everything is good so far. The problem is I have a type in module A Type1 which is used in module 2. But in my ios App if I try to use them together I have an incompatibility error where A.Type1 is said to be incompatible with B.Type1. Whereas they are supposed to be the exactly the same. How can I solve that?

NSBundle.localizedStringForKey

doesn't work properly in pair with

NSString.localizedStringWithFormat

. Looks like

NSString

losing some metadata during conversion into Kotlin

String

. Here is example on Kotlin:

import platform.Foundation.NSBundle
import platform.Foundation.NSString
import platform.Foundation.localizedStringWithFormat

class TestClass(private val bundle: NSBundle) {
    fun localizedStringWithFormat(string: String): String {
        return NSString.localizedStringWithFormat(
                this.bundle.localizedStringForKey(string, "", "Localizable"), 5)
    }
}

Here is the code in swift:

let testClass = TestClass(bundle: Bundle.main)
let testString = "screen_main_plural_string"
let nativeStr = Bundle.main.localizedString(forKey: testString, value: "", table: "Localizable") as NSString

NSLog("swift: %@", NSString.localizedStringWithFormat(nativeStr, 5))
NSLog("kotlin: %@", testClass.localizedStringWithFormat(string: testString))

Output logs: swift: Plural: 5 apples kotlin: %#@value@

FreezableAtomicReference was introduced in Kotlin 1.3.40 and according to its release notes (https://blog.jetbrains.com/kotlin/2019/06/kotlin-1-3-40-released/) it was considered as experimental. No changes were made since its initial implementation. What is the status of it? Are there any known issues? Thanks!

Hey guys, I am building iOS fat framework and everything seems to be working fine on my iOS app. However I have this warning in the build logs:

w: Interop library /pathToUser/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlinx/kotlinx-io-iosarm64/0.1.14/1ece4fc59ccddcacf23bb04589c7c0f39a94b787/kotlinx-io-cinterop-sockets can't be exported with -Xexport-library

. Will I experience runtime crashes ? what does it mean exactly for the framework produced ?

Hello, do Kotlin enums become real ObjC enums (which are objects after all) or are they like real enums (two values share the same memory instance?

And what about nullability in Kotlin, does it translate correctly when used in Swift through ObjC?

The new plugin for debugging K/N in IntelliJ seems to be corrupting my multiplatform projects... If I have it installed and activated, it changes the type of my modules to KONAN_NATIVE, which the normal Kotlin plugin doesn't like, and thus refuses to load.

Hi, in my Kotlin/native project

.....
var outputLength = cValuesOf(0)
......
val outputBA = outputData.readBytes(outputLength convert int)

How to Convert outputLength to Int Thanks

Is there some consideration being made about including wrappers to cover some common C Macros, which are in the bundled C libraries (varies by target)?

hi, I write enum in my commonMain at K/N project, then build .so for Android. Now how can I use this enum ?? thanks~

Trying to get a list of devs/companies working with KMP going here - feel free to add to the list! https://twitter.com/justinmkaufman/status/1169650267135991808?s=21

Hi, Is it possible to get context at androidNativeArm64 ??? Because I Must Build Library include .so for Android(can’t use androidMain) + .framework for iOS Ex: getPackageName…. I think it is no. Then some ways to do this? Thanks

Has anyone else experienced issues with NSObjects not being deallocated properly? I have a function that is called in a loop which allocates an NSObject (NSProcessInfo) but it never gets deallocated My loop runs for 150 ms and during that time application memory usage typically rises by ~50 MB, and when profiling I see it is because there are thousands of NSProcessInfo objects that never get deallocated (each one is only 4 KB)

fun elapsedRealtime() = (NSProcessInfo().systemUptime * 1_000)

val startTime = elapsedRealtime()
var currentTime = startTime
while (currentTime - startTime < 150) {
    currentTime = elapsedRealTime()
}

I would think NSProcessInfo objects should automatically be deallocated each time

elapsedRealtime

completes since the reference count would be 0, but I am unsure how Kotlin’s GC interacts with Swift/Objective-C’s ARC If I change the loop to run for 25 seconds for example my memory usage shoots up nearly 500 MB. This is running on macOS 10.14.6