| // Copyright 2011 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef BASE_PENDING_TASK_H_ |
| #define BASE_PENDING_TASK_H_ |
| |
| #include<array> |
| |
| #include"base/base_export.h" |
| #include"base/functional/callback.h" |
| #include"base/location.h" |
| #include"base/task/delay_policy.h" |
| #include"base/time/time.h" |
| |
| namespacebase{ |
| |
| enumclassNestable:uint8_t{ |
| kNonNestable, |
| kNestable, |
| }; |
| |
| // Copyable data part of PendingTask. |
| struct BASE_EXPORTTaskMetadata{ |
| TaskMetadata(); |
| explicitTaskMetadata(constLocation& posted_from, |
| TimeTicks queue_time=TimeTicks(), |
| TimeTicks delayed_run_time=TimeTicks(), |
| TimeDelta leeway=TimeDelta(), |
| subtle::DelayPolicy delay_policy= |
| subtle::DelayPolicy::kFlexibleNoSooner); |
| TaskMetadata(TaskMetadata&& other); |
| TaskMetadata(constTaskMetadata& other); |
| ~TaskMetadata(); |
| |
| TaskMetadata&operator=(TaskMetadata&& other); |
| TaskMetadata&operator=(constTaskMetadata& other); |
| |
| // Returns the time at which this task should run. This is |delayed_run_time| |
| // for a delayed task, |queue_time| otherwise. |
| base::TimeTicksGetDesiredExecutionTime()const; |
| |
| TimeTicks earliest_delayed_run_time()const; |
| TimeTicks latest_delayed_run_time()const; |
| |
| // The site this PendingTask was posted from. |
| Location posted_from; |
| |
| // The time at which the task was queued, which happens at post time. For |
| // deferred non-nestable tasks, this is reset when the nested loop exits and |
| // the deferred tasks are pushed back at the front of the queue. This is not |
| // set for immediate SequenceManager tasks unless SetAddQueueTimeToTasks(true) |
| // was called. This defaults to a null TimeTicks if the task hasn't been |
| // inserted in a sequence yet. |
| TimeTicks queue_time; |
| |
| // The time when the task should be run. This is null for an immediate task. |
| base::TimeTicks delayed_run_time; |
| |
| // |leeway| and |delay_policy| determine the preferred time range for running |
| // the delayed task. A larger leeway provides more freedom to run the task at |
| // an optimal time for power consumption. These fields are ignored for an |
| // immediate (non-delayed) task. |
| TimeDelta leeway; |
| subtle::DelayPolicy delay_policy= subtle::DelayPolicy::kFlexibleNoSooner; |
| |
| // Chain of symbols of the parent tasks which led to this one being posted. |
| staticconstexprsize_t kTaskBacktraceLength=4; |
| std::array<constvoid*, kTaskBacktraceLength> task_backtrace={}; |
| |
| // The context of the IPC message that was being handled when this task was |
| // posted. This is a hash of the IPC message name that is set within the scope |
| // of an IPC handler and when symbolized uniquely identifies the message being |
| // processed. This property is not propagated from one PendingTask to the |
| // next. For example, if pending task A was posted while handling an IPC, |
| // and pending task B was posted from within pending task A, then pending task |
| // B will not inherit the |ipc_hash| of pending task A. |
| uint32_t ipc_hash=0; |
| constchar* ipc_interface_name=nullptr; |
| |
| // Secondary sort key for run time. |
| int sequence_num=0; |
| |
| bool task_backtrace_overflow=false; |
| }; |
| |
| // Contains data about a pending task. Stored in TaskQueue and DelayedTaskQueue |
| // for use by classes that queue and execute tasks. |
| struct BASE_EXPORTPendingTask:publicTaskMetadata{ |
| PendingTask(); |
| PendingTask(constLocation& posted_from, |
| OnceClosure task, |
| TimeTicks queue_time=TimeTicks(), |
| TimeTicks delayed_run_time=TimeTicks(), |
| TimeDelta leeway=TimeDelta(), |
| subtle::DelayPolicy delay_policy= |
| subtle::DelayPolicy::kFlexibleNoSooner); |
| PendingTask(constTaskMetadata& metadata,OnceClosure task); |
| PendingTask(PendingTask&& other); |
| ~PendingTask(); |
| |
| PendingTask&operator=(PendingTask&& other); |
| |
| // The task to run. |
| OnceClosure task; |
| }; |
| |
| }// namespace base |
| |
| #endif// BASE_PENDING_TASK_H_ |
