Revert "Move mojo edk into mojo/edk"

mojo/edk/system/waiter.cc

-// 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.
-
-#include "mojo/edk/system/waiter.h"
-
-#include <limits>
-
-#include "base/logging.h"
-#include "base/time/time.h"
-
-namespace mojo {
-namespace system {
-
-Waiter::Waiter()
-    : cv_(&lock_),
-#ifndef NDEBUG
-      initialized_(false),
-#endif
-      awoken_(false),
-      awake_result_(MOJO_RESULT_INTERNAL),
-      awake_context_(static_cast<uint32_t>(-1)) {
-}
-
-Waiter::~Waiter() {
-}
-
-void Waiter::Init() {
-#ifndef NDEBUG
-  initialized_ = true;
-#endif
-  awoken_ = false;
-  // NOTE(vtl): If performance ever becomes an issue, we can disable the setting
-  // of |awake_result_| (except the first one in |Awake()|) in Release builds.
-  awake_result_ = MOJO_RESULT_INTERNAL;
-}
-
-// TODO(vtl): Fast-path the |deadline == 0| case?
-MojoResult Waiter::Wait(MojoDeadline deadline, uint32_t* context) {
-  base::AutoLock locker(lock_);
-
-#ifndef NDEBUG
-  DCHECK(initialized_);
-  // It'll need to be re-initialized after this.
-  initialized_ = false;
-#endif
-
-  // Fast-path the already-awoken case:
-  if (awoken_) {
-    DCHECK_NE(awake_result_, MOJO_RESULT_INTERNAL);
-    if (context)
-      *context = awake_context_;
-    return awake_result_;
-  }
-
-  // |MojoDeadline| is actually a |uint64_t|, but we need a signed quantity.
-  // Treat any out-of-range deadline as "forever" (which is wrong, but okay
-  // since 2^63 microseconds is ~300000 years). Note that this also takes care
-  // of the |MOJO_DEADLINE_INDEFINITE| (= 2^64 - 1) case.
-  if (deadline > static_cast<uint64_t>(std::numeric_limits<int64_t>::max())) {
-    do {
-      cv_.Wait();
-    } while (!awoken_);
-  } else {
-    // NOTE(vtl): This is very inefficient on POSIX, since pthreads condition
-    // variables take an absolute deadline.
-    const base::TimeTicks end_time =
-        base::TimeTicks::Now() +
-        base::TimeDelta::FromMicroseconds(static_cast<int64_t>(deadline));
-    do {
-      base::TimeTicks now_time = base::TimeTicks::Now();
-      if (now_time >= end_time)
-        return MOJO_RESULT_DEADLINE_EXCEEDED;
-
-      cv_.TimedWait(end_time - now_time);
-    } while (!awoken_);
-  }
-
-  DCHECK_NE(awake_result_, MOJO_RESULT_INTERNAL);
-  if (context)
-    *context = awake_context_;
-  return awake_result_;
-}
-
-void Waiter::Awake(MojoResult result, uint32_t context) {
-  base::AutoLock locker(lock_);
-
-  if (awoken_)
-    return;
-
-  awoken_ = true;
-  awake_result_ = result;
-  awake_context_ = context;
-  cv_.Signal();
-  // |cv_.Wait()|/|cv_.TimedWait()| will return after |lock_| is released.
-}
-
-}  // namespace system
-}  // namespace mojo