Mojo: Move waiting APIs to public library

mojo/edk/system/waiter_test_utils.h

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef MOJO_EDK_SYSTEM_WAITER_TEST_UTILS_H_
-#define MOJO_EDK_SYSTEM_WAITER_TEST_UTILS_H_
-
-#include <stdint.h>
-
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/threading/simple_thread.h"
-#include "mojo/edk/system/dispatcher.h"
-#include "mojo/edk/system/handle_signals_state.h"
-#include "mojo/edk/system/waiter.h"
-#include "mojo/public/c/system/types.h"
-
-namespace mojo {
-namespace edk {
-namespace test {
-
-// This is a very simple thread that has a |Waiter|, on which it waits
-// indefinitely (and records the result). It will create and initialize the
-// |Waiter| on creation, but the caller must start the thread with |Start()|. It
-// will join the thread on destruction.
-//
-// One usually uses it like:
-//
-//    MojoResult result;
-//    {
-//      AwakableList awakable_list;
-//      test::SimpleWaiterThread thread(&result);
-//      awakable_list.Add(thread.waiter(), ...);
-//      thread.Start();
-//      ... some stuff to wake the waiter ...
-//      awakable_list.Remove(thread.waiter());
-//    }  // Join |thread|.
-//    EXPECT_EQ(..., result);
-//
-// There's a bit of unrealism in its use: In this sort of usage, calls such as
-// |Waiter::Init()|, |AddAwakable()|, and |RemoveAwakable()| are done in the
-// main (test) thread, not the waiter thread (as would actually happen in real
-// code). (We accept this unrealism for simplicity, since |AwakableList| is
-// thread-unsafe so making it more realistic would require adding nontrivial
-// synchronization machinery.)
-class SimpleWaiterThread : public base::SimpleThread {
- public:
-  // For the duration of the lifetime of this object, |*result| belongs to it
-  // (in the sense that it will write to it whenever it wants).
-  SimpleWaiterThread(MojoResult* result, uintptr_t* context);
-  ~SimpleWaiterThread() override;  // Joins the thread.
-
-  Waiter* waiter() { return &waiter_; }
-
- private:
-  void Run() override;
-
-  MojoResult* const result_;
-  uintptr_t* const context_;
-  Waiter waiter_;
-
-  DISALLOW_COPY_AND_ASSIGN(SimpleWaiterThread);
-};
-
-// This is a more complex and realistic thread that has a |Waiter|, on which it
-// waits for the given deadline (with the given flags). Unlike
-// |SimpleWaiterThread|, it requires the machinery of |Dispatcher|.
-class WaiterThread : public base::SimpleThread {
- public:
-  // Note: |*did_wait_out|, |*result_out|, |*context_out| and
-  // |*signals_state_out| "belong" to this object (i.e., may be modified by, on
-  // some other thread) while it's alive.
-  WaiterThread(scoped_refptr<Dispatcher> dispatcher,
-               MojoHandleSignals handle_signals,
-               MojoDeadline deadline,
-               uintptr_t context,
-               bool* did_wait_out,
-               MojoResult* result_out,
-               uintptr_t* context_out,
-               HandleSignalsState* signals_state_out);
-  ~WaiterThread() override;
-
- private:
-  void Run() override;
-
-  const scoped_refptr<Dispatcher> dispatcher_;
-  const MojoHandleSignals handle_signals_;
-  const MojoDeadline deadline_;
-  const uint32_t context_;
-  bool* const did_wait_out_;
-  MojoResult* const result_out_;
-  uintptr_t* const context_out_;
-  HandleSignalsState* const signals_state_out_;
-
-  Waiter waiter_;
-
-  DISALLOW_COPY_AND_ASSIGN(WaiterThread);
-};
-
-}  // namespace test
-}  // namespace edk
-}  // namespace mojo
-
-#endif  // MOJO_EDK_SYSTEM_WAITER_TEST_UTILS_H_