Define Stable API for WebRTC/Quartc

net/quic/quartc/quartc_task_runner_interface.h

+// Copyright (c) 2016 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 NET_QUIC_QUARTC_QUARTC_TASKRUNNER_INTERFACE_H_
+#define NET_QUIC_QUARTC_QUARTC_TASKRUNNER_INTERFACE_H_
+
+#include <stdint.h>
+
+#include <memory>
+
+namespace net {
+
+// Used by platform specific QuicAlarms. For example, WebRTC will use it to set
+// and cancel an alarm. When setting an alarm, the task runner will schedule a
+// task on rtc::Thread. When canceling an alarm, the canceler for that task will
+// be called.
+class QuartcTaskRunnerInterface {
+ public:
+  virtual ~QuartcTaskRunnerInterface() {}
+
+  class Task {
+   public:
+    virtual ~Task() {}
+
+    // Called when it's time to start the task.
+    virtual void Run() = 0;
+  };
+
+  // A handler used to cancel a scheduled task. In some cases, a task cannot
+  // be directly canceled with its pointer. For example, in WebRTC, the task
+  // will be scheduled on rtc::Thread. When canceling a task, its pointer cannot
+  // locate the scheduled task in the thread message queue. So when scheduling a
+  // task, an additional handler (ScheduledTask) will be returned.
+  class ScheduledTask {
+   public:
+    virtual ~ScheduledTask() {}
+
+    // Cancels a scheduled task, meaning the task will not be run.
+    virtual void Cancel() = 0;
+  };
+
+  // Schedules a task, which will be run after the given delay. A ScheduledTask
+  // may be used to cancel the task.
+  virtual std::unique_ptr<ScheduledTask> Schedule(Task* task,
+                                                  uint64_t delay_ms) = 0;
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_QUARTC_QUARTC_TASKRUNNER_INTERFACE_H_