Platform library for iconv.h on macos, ios and linux.

backend.native/tests/interop/libiconv.kt

@@ -0,0 +1,39 @@
+import kotlinx.cinterop.*
+import platform.iconv.*
+import platform.posix.size_tVar
+
+fun main(args: Array<String>) {
+
+    val sourceByteArray = "Hello!".toUtf8()
+
+    val golden = listOf(0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x21)
+
+    memScoped {
+
+        val sourceLength = alloc<size_tVar>()
+        val destLength = alloc<size_tVar>()
+
+        val sourceBytes = allocArrayOf(sourceByteArray)
+        val destBytes = allocArray<ByteVar>(golden.size)
+
+        val sourcePtr = alloc<CArrayPointerVar<ByteVar>>()
+        sourcePtr.value = sourceBytes
+
+        val destPtr = alloc<CArrayPointerVar<ByteVar>>()
+        destPtr.value = destBytes
+
+        sourceLength.value = sourceByteArray.size.signExtend();
+        destLength.value = golden.size.signExtend();
+
+        val conversion = iconv_open("UTF-8", "LATIN1")
+
+        iconv(conversion, sourcePtr.ptr, sourceLength.ptr, destPtr.ptr, destLength.ptr)
+
+        golden.forEachIndexed { index, it ->
+            println("$it ${destBytes[index]}")
+            it == destBytes[index].toInt()
+        }
+
+        iconv_close(conversion)
+    }
+}