Implementation of SequencedTaskRunner based on SequencedWorkerPool.

base/sequenced_task_runner_impl.cc

+// Copyright (c) 2012 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 "sequenced_task_runner_impl.h"
+
+#include "base/logging.h"
+#include "base/threading/sequenced_worker_pool.h"
+
+namespace base {
+
+// Thin wrapper for SequencedWorkerPool::SequenceToken used to obviate the
+// need to include the SequencedWorkerPool header in this file's header.
+class SequencedTaskRunnerImpl::SequenceToken {
+ public:
+  explicit SequenceToken(const SequencedWorkerPool::SequenceToken token)
+      : value_(token) {
+  }
+  operator SequencedWorkerPool::SequenceToken() const {
+    return value_;
+  }
+ private:
+  SequencedWorkerPool::SequenceToken value_;
+};
+
+SequencedTaskRunnerImpl::SequencedTaskRunnerImpl(
+    scoped_refptr<SequencedWorkerPool> pool)
+    : pool_(pool),
+      token_(new SequenceToken(pool_->GetSequenceToken())) {
+}
+
+SequencedTaskRunnerImpl::~SequencedTaskRunnerImpl() {
+}
+
+bool SequencedTaskRunnerImpl::PostDelayedTask(
+    const tracked_objects::Location& from_here,
+    const Closure& task,
+    int64 delay_ms) {
+  return pool_->PostDelayedTask(from_here, task, delay_ms);
+}
+
+bool SequencedTaskRunnerImpl::PostDelayedTask(
+    const tracked_objects::Location& from_here,
+    const Closure& task,
+    TimeDelta delay) {
+  return pool_->PostDelayedTask(from_here, task, delay);
+}
+
+bool SequencedTaskRunnerImpl::RunsTasksOnCurrentThread() const {
+  return pool_->RunsTasksOnCurrentThread();
+}
+
+bool SequencedTaskRunnerImpl::PostNonNestableDelayedTask(
+    const tracked_objects::Location& from_here,
+    const Closure& task,
+    int64 delay_ms) {
+  // TODO(francoisk777@gmail.com): Change the following two statements once
+  // SequencedWorkerPool supports non-zero delays.
+  DLOG_IF(WARNING, (delay_ms != 0)) << "SequencedTaskRunnerImpl does not yet "

[akalin, 2012/03/13 07:27:11]

probably should change this to NOTREACHED, analogous to SWP

[Francois, 2012/03/14 15:43:31]

Done.

+      "support non-zero delays; ignoring delay of " << delay_ms << " ms";
+  return pool_->PostSequencedWorkerTask(*token_, from_here, task);
+}
+
+bool SequencedTaskRunnerImpl::PostNonNestableDelayedTask(
+    const tracked_objects::Location& from_here,
+    const Closure& task,
+    base::TimeDelta delay) {
+  // TODO(francoisk777@gmail.com): Change the following two statements once
+  // SequencedWorkerPool supports non-zero delays.
+  DLOG_IF(WARNING, (delay.InMillisecondsRoundedUp() != 0))
+      << "SequencedTaskRunnerImpl does not yet support non-zero delays; "
+      "ignoring delay of " << delay.InMillisecondsRoundedUp();
+  return pool_->PostSequencedWorkerTask(*token_, from_here, task);
+}
+
+}  // namespace base