1 files changed, 49 insertions, 0 deletions
diff --git a/kotlinx-coroutines-core/jvm/src/EventLoop.kt b/kotlinx-coroutines-core/jvm/src/EventLoop.kt
new file mode 100644
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+++ b/kotlinx-coroutines-core/jvm/src/EventLoop.kt
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.coroutines
+
+internal actual abstract class EventLoopImplPlatform: EventLoop() {
+    protected abstract val thread: Thread
+
+    protected actual fun unpark() {
+        val thread = thread // atomic read
+        if (Thread.currentThread() !== thread)
+            unpark(thread)
+    }
+
+    protected actual fun reschedule(now: Long, delayedTask: EventLoopImplBase.DelayedTask) {
+        assert { this !== DefaultExecutor } // otherwise default execution was shutdown with tasks in it (cannot be)
+        DefaultExecutor.schedule(now, delayedTask)
+    }
+}
+
+internal class BlockingEventLoop(
+    override val thread: Thread
+) : EventLoopImplBase()
+
+internal actual fun createEventLoop(): EventLoop = BlockingEventLoop(Thread.currentThread())
+
+/**
+ * Processes next event in the current thread's event loop.
+ *
+ * The result of this function is to be interpreted like this:
+ * * `<= 0` -- there are potentially more events for immediate processing;
+ * * `> 0` -- a number of nanoseconds to wait for the next scheduled event;
+ * * [Long.MAX_VALUE] -- no more events or no thread-local event loop.
+ *
+ * Sample usage of this function:
+ *
+ * ```
+ * while (waitingCondition) {
+ *     val time = processNextEventInCurrentThread()
+ *     LockSupport.parkNanos(time)
+ * }
+ * ```
+ *
+ * @suppress **This an internal API and should not be used from general code.**
+ */
+@InternalCoroutinesApi
+public fun processNextEventInCurrentThread(): Long =
+    ThreadLocalEventLoop.currentOrNull()?.processNextEvent() ?: Long.MAX_VALUE
+\ No newline at end of file