1 files changed, 104 insertions, 0 deletions
diff --git a/kotlinx-coroutines-core/native/src/internal/CopyOnWriteList.kt b/kotlinx-coroutines-core/native/src/internal/CopyOnWriteList.kt
new file mode 100644
index 00000000..c81f6530
--- /dev/null
+++ b/kotlinx-coroutines-core/native/src/internal/CopyOnWriteList.kt
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2016-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.coroutines.internal
+
+@Suppress("UNCHECKED_CAST")
+internal class CopyOnWriteList<E>(private var array: Array<Any?> = arrayOfNulls(4)) : AbstractMutableList<E>() {
+
+    private var _size = 0
+    override val size: Int get() = _size
+
+    override fun add(element: E): Boolean {
+        val newSize = if (_size == array.size) array.size * 2 else  array.size
+        val update = array.copyOf(newSize)
+        update[_size++] = element
+        array = update
+        return true
+    }
+
+    override fun add(index: Int, element: E) {
+        rangeCheck(index)
+        val update = arrayOfNulls<Any?>(if (array.size == _size) array.size * 2 else array.size)
+        array.copyInto(
+            destination = update,
+            endIndex = index
+        )
+        update[index] = element
+        array.copyInto(
+            destination = update,
+            destinationOffset = index + 1,
+            startIndex = index,
+            endIndex = _size + 1
+        )
+        ++_size
+        array = update
+    }
+
+    override fun remove(element: E): Boolean {
+        val index = array.indexOf(element as Any)
+        if (index == -1) {
+            return false
+        }
+
+        removeAt(index)
+        return true
+    }
+
+    override fun removeAt(index: Int): E {
+        rangeCheck(index)
+        modCount++
+        val n = array.size
+        val element = array[index]
+        val update = arrayOfNulls<Any>(n)
+        array.copyInto(
+            destination = update,
+            endIndex = index
+        )
+        array.copyInto(
+            destination = update,
+            destinationOffset = index,
+            startIndex = index + 1,
+            endIndex = n
+        )
+        array = update
+        --_size
+        return element as E
+    }
+
+    override fun iterator(): MutableIterator<E> = IteratorImpl(array as Array<E>, size)
+
+    override fun listIterator(): MutableListIterator<E> = throw UnsupportedOperationException("Operation is not supported")
+
+    override fun listIterator(index: Int): MutableListIterator<E> = throw UnsupportedOperationException("Operation is not supported")
+
+    override fun isEmpty(): Boolean = size == 0
+
+    override fun set(index: Int, element: E): E = throw UnsupportedOperationException("Operation is not supported")
+
+    override fun get(index: Int): E = array[rangeCheck(index)]!! as E
+
+    private class IteratorImpl<E>(private var array: Array<E>, private val size: Int) : MutableIterator<E> {
+
+        private var current = 0
+
+        override fun hasNext(): Boolean = current != size
+
+        override fun next(): E {
+            if (!hasNext()) {
+                throw NoSuchElementException()
+            }
+
+            return array[current++]!!
+        }
+
+        override fun remove() = throw UnsupportedOperationException("Operation is not supported")
+    }
+
+    private fun rangeCheck(index: Int) = index.apply {
+        if (index < 0 || index >= _size) {
+            throw IndexOutOfBoundsException("index: $index, size: $size")
+        }
+    }
+}