Hi guys, I am trying to return to a C program a s...

# embedded-kotlin

[Vlad Balan]

Hi guys,

I am trying to return to a C program a struct pointer allocated in Kotlin Native.

The struct:

typedef struct {
    uint8_t a;
} testStructDto;

is translated in Kotlin as follows:

@kotlinx.cinterop.internal.CStruct public final class testStructDto public constructor(rawPtr: kotlinx.cinterop.NativePtr /* = kotlin.native.internal.NativePtr */) : kotlinx.cinterop.CStructVar {
    public companion object : kotlinx.cinterop.CStructVar.Type {
    }

    public final var a: liboverlay.uint8_t /* = kotlin.UByte */ /* compiled code */
}

My Kotlin native function:

@ExperimentalUnsignedTypes
	override fun init(): CPointer<testStructDto> {
		val dtoVar = nativeHeap.alloc<testStructDto>()
		dtoVar.a = 0xa5.toUByte()

		return dtoVar.ptr
	}

I can use it in Kotlin like this:

@Test
	fun `initialize`() {
		val context = controller.init()

		assertEquals(0xa5.toUByte(), context.pointed.a)
	}

But when I try to use it in C like this:

libtest_ExportedSymbols *libPtr = libtest_symbols()
libtest_kref_MyObjectFactory kFactory = libPtr->kotlin.root.MyObjectFactory._instance();
libtest_kref_MyObject kObject = libPtr->kotlin.MyObjectFactory.create(kFactory);
testStructDto *dto = (testStructDto *) libPtr->kotlin.root.MyObject.init(kObject);

I always get

dto->a = 32

I get the value 32 even if I assign something else than 0xa5 .

Does anybody know what I am doing wrong?

Thanks in advance!
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