Added addressOf for Pinned<String> and Pinned<CharArray> (#3783)

Interop/Runtime/src/native/kotlin/kotlinx/cinterop/Pinning.kt

@@ -47,6 +47,12 @@ inline fun <T : Any, R> T.usePinned(block: (Pinned<T>) -> R): R {
 fun Pinned<ByteArray>.addressOf(index: Int): CPointer<ByteVar> = this.get().addressOfElement(index)
 fun ByteArray.refTo(index: Int): CValuesRef<ByteVar> = this.usingPinned { addressOf(index) }
 
+fun Pinned<String>.addressOf(index: Int): CPointer<COpaque> = this.get().addressOfElement(index)
+fun String.refTo(index: Int): CValuesRef<COpaque> = this.usingPinned { addressOf(index) }
+
+fun Pinned<CharArray>.addressOf(index: Int): CPointer<COpaque> = this.get().addressOfElement(index)
+fun CharArray.refTo(index: Int): CValuesRef<COpaque> = this.usingPinned { addressOf(index) }
+
 fun Pinned<ShortArray>.addressOf(index: Int): CPointer<ShortVar> = this.get().addressOfElement(index)
 fun ShortArray.refTo(index: Int): CValuesRef<ShortVar> = this.usingPinned { addressOf(index) }
 
@@ -89,6 +95,12 @@ private inline fun <T : Any, P : CPointed> T.usingPinned(
 @SymbolName("Kotlin_Arrays_getByteArrayAddressOfElement")
 private external fun ByteArray.addressOfElement(index: Int): CPointer<ByteVar>
 
+@SymbolName("Kotlin_Arrays_getStringAddressOfElement")
+private external fun String.addressOfElement(index: Int): CPointer<COpaque>
+
+@SymbolName("Kotlin_Arrays_getCharArrayAddressOfElement")
+private external fun CharArray.addressOfElement(index: Int): CPointer<COpaque>
+
 @SymbolName("Kotlin_Arrays_getShortArrayAddressOfElement")
 private external fun ShortArray.addressOfElement(index: Int): CPointer<ShortVar>
 

runtime/src/main/cpp/Arrays.cpp

@@ -661,6 +661,15 @@ KNativePtr Kotlin_Arrays_getByteArrayAddressOfElement(KRef thiz, KInt index) {
   return AddressOfElementAt<KByte>(array, index);
 }
 
+KNativePtr Kotlin_Arrays_getCharArrayAddressOfElement (KRef thiz, KInt index) {
+  ArrayHeader* array = thiz->array();
+  return CharArrayAddressOfElementAt(array, index);
+}
+
+KNativePtr Kotlin_Arrays_getStringAddressOfElement (KRef thiz, KInt index) {
+  return Kotlin_Arrays_getCharArrayAddressOfElement(thiz, index);
+}
+
 KNativePtr Kotlin_Arrays_getShortArrayAddressOfElement(KRef thiz, KInt index) {
   ArrayHeader* array = thiz->array();
   if (index < 0 || index >= array->count_) {