import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

xpcom/threads/nsIThread.idl

@@ -0,0 +1,149 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIEventTarget.idl"
+#include "nsIIdlePeriod.idl"
+
+%{C++
+#include "mozilla/AlreadyAddRefed.h"
+%}
+
+[ptr] native PRThread(PRThread);
+
+native alreadyAddRefed_nsIIdlePeriod(already_AddRefed<nsIIdlePeriod>);
+
+/**
+ * This interface provides a high-level abstraction for an operating system
+ * thread.
+ *
+ * Threads have a built-in event queue, and a thread is an event target that
+ * can receive nsIRunnable objects (events) to be processed on the thread.
+ *
+ * See nsIThreadManager for the API used to create and locate threads.
+ */
+[scriptable, uuid(5801d193-29d1-4964-a6b7-70eb697ddf2b)]
+interface nsIThread : nsIEventTarget
+{
+  /**
+   * @returns
+   *   The NSPR thread object corresponding to this nsIThread.
+   */
+  [noscript] readonly attribute PRThread PRThread;
+
+  /**
+   * @returns
+   *  Whether or not this thread may call into JS. Used in the profiler
+   *  to avoid some unnecessary locking.
+   */
+  [noscript] attribute boolean CanInvokeJS;
+
+
+  /**
+   * Shutdown the thread.  This method prevents further dispatch of events to
+   * the thread, and it causes any pending events to run to completion before
+   * the thread joins (see PR_JoinThread) with the current thread.  During this
+   * method call, events for the current thread may be processed.
+   *
+   * This method MAY NOT be executed from the thread itself.  Instead, it is
+   * meant to be executed from another thread (usually the thread that created
+   * this thread or the main application thread).  When this function returns,
+   * the thread will be shutdown, and it will no longer be possible to dispatch
+   * events to the thread.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   Indicates that this method was erroneously called when this thread was
+   *   the current thread, that this thread was not created with a call to
+   *   nsIThreadManager::NewThread, or if this method was called more than once
+   *   on the thread object.
+   */
+  void shutdown();
+
+  /**
+   * This method may be called to determine if there are any events ready to be
+   * processed.  It may only be called when this thread is the current thread.
+   *
+   * Because events may be added to this thread by another thread, a "false"
+   * result does not mean that this thread has no pending events.  It only
+   * means that there were no pending events when this method was called.
+   *
+   * @returns
+   *   A boolean value that if "true" indicates that this thread has one or
+   *   more pending events.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   Indicates that this method was erroneously called when this thread was
+   *   not the current thread.
+   */
+  boolean hasPendingEvents();
+
+  /**
+   * Process the next event.  If there are no pending events, then this method
+   * may wait -- depending on the value of the mayWait parameter -- until an
+   * event is dispatched to this thread.  This method is re-entrant but may
+   * only be called if this thread is the current thread.
+   *
+   * @param mayWait
+   *   A boolean parameter that if "true" indicates that the method may block
+   *   the calling thread to wait for a pending event.
+   *
+   * @returns
+   *   A boolean value that if "true" indicates that an event was processed.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   Indicates that this method was erroneously called when this thread was
+   *   not the current thread.
+   */
+  boolean processNextEvent(in boolean mayWait);
+
+  /**
+   * Shutdown the thread asynchronously.  This method immediately prevents
+   * further dispatch of events to the thread, and it causes any pending events
+   * to run to completion before this thread joins with the current thread.
+   *
+   * UNLIKE shutdown() this does not process events on the current thread.
+   * Instead it merely ensures that the current thread continues running until
+   * this thread has shut down.
+   *
+   * This method MAY NOT be executed from the thread itself.  Instead, it is
+   * meant to be executed from another thread (usually the thread that created
+   * this thread or the main application thread).  When this function returns,
+   * the thread will continue running until it exhausts its event queue.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   Indicates that this method was erroneously called when this thread was
+   *   the current thread, that this thread was not created with a call to
+   *   nsIThreadManager::NewThread, or if this method was called more than once
+   *   on the thread object.
+   */
+  void asyncShutdown();
+
+  /**
+   * Register an instance of nsIIdlePeriod which works as a facade of
+   * the abstract notion of a "current idle period". The
+   * nsIIdlePeriod should always represent the "current" idle period
+   * with regard to expected work for the thread. The thread is free
+   * to use this when there are no higher prioritized tasks to process
+   * to determine if it is reasonable to schedule tasks that could run
+   * when the thread is idle. The responsibility of the registered
+   * nsIIdlePeriod is to answer with an estimated deadline at which
+   * the thread should expect that it could receive new higher
+   * priority tasks.
+   */
+  [noscript] void registerIdlePeriod(in alreadyAddRefed_nsIIdlePeriod aIdlePeriod);
+
+  /**
+   * Dispatch an event to the thread's idle queue.  This function may be called
+   * from any thread, and it may be called re-entrantly.
+   *
+   * @param event
+   *   The alreadyAddRefed<> event to dispatch.
+   *   NOTE that the event will be leaked if it fails to dispatch.
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   Indicates that event is null.
+   */
+  [noscript] void idleDispatch(in alreadyAddRefed_nsIRunnable event);
+};