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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "nsISerialEventTarget.idl"
#include "nsIThreadShutdown.idl"
%{C++
#include "mozilla/AlreadyAddRefed.h"
namespace mozilla {
class TimeStamp;
class TimeDurationValueCalculator;
template <typename T> class BaseTimeDuration;
typedef BaseTimeDuration<TimeDurationValueCalculator> TimeDuration;
enum class EventQueuePriority;
}
%}
[ptr] native PRThread(PRThread);
native EventQueuePriority(mozilla::EventQueuePriority);
native nsIEventTargetPtr(nsIEventTarget*);
native nsISerialEventTargetPtr(nsISerialEventTarget*);
native TimeStamp(mozilla::TimeStamp);
native TimeDuration(mozilla::TimeDuration);
/**
* This interface provides a high-level abstraction for an operating system
* thread.
*
* Threads have a built-in event queue, and a thread is an event target that
* can receive nsIRunnable objects (events) to be processed on the thread.
*
* See nsIThreadManager for the API used to create and locate threads.
*/
[builtinclass, scriptable, rust_sync, uuid(5801d193-29d1-4964-a6b7-70eb697ddf2b)]
interface nsIThread : nsISerialEventTarget
{
/**
* @returns
* The NSPR thread object corresponding to this nsIThread.
*/
[noscript] readonly attribute PRThread PRThread;
/**
* @returns
* Whether or not this thread may call into JS. Used in the profiler
* to avoid some unnecessary locking.
*/
[noscript] attribute boolean CanInvokeJS;
/**
* Thread QoS priorities. Currently only supported on MacOS.
*/
cenum QoSPriority : 32 {
QOS_PRIORITY_NORMAL,
QOS_PRIORITY_LOW
};
/**
* Shutdown the thread. This method prevents further dispatch of events to
* the thread, and it causes any pending events to run to completion before
* the thread joins (see PR_JoinThread) with the current thread. During this
* method call, events for the current thread may be processed.
*
* This method MAY NOT be executed from the thread itself. Instead, it is
* meant to be executed from another thread (usually the thread that created
* this thread or the main application thread). When this function returns,
* the thread will be shutdown, and it will no longer be possible to dispatch
* events to the thread.
*
* @throws NS_ERROR_UNEXPECTED
* Indicates that this method was erroneously called when this thread was
* the current thread, that this thread was not created with a call to
* nsIThreadManager::NewThread, or if this method was called more than once
* on the thread object.
*/
void shutdown();
/**
* This method may be called to determine if there are any events ready to be
* processed. It may only be called when this thread is the current thread.
*
* Because events may be added to this thread by another thread, a "false"
* result does not mean that this thread has no pending events. It only
* means that there were no pending events when this method was called.
*
* @returns
* A boolean value that if "true" indicates that this thread has one or
* more pending events.
*
* @throws NS_ERROR_UNEXPECTED
* Indicates that this method was erroneously called when this thread was
* not the current thread.
*/
boolean hasPendingEvents();
/**
* Similar to above, but checks only possible high priority queue.
*/
boolean hasPendingHighPriorityEvents();
/**
* Process the next event. If there are no pending events, then this method
* may wait -- depending on the value of the mayWait parameter -- until an
* event is dispatched to this thread. This method is re-entrant but may
* only be called if this thread is the current thread.
*
* @param mayWait
* A boolean parameter that if "true" indicates that the method may block
* the calling thread to wait for a pending event.
*
* @returns
* A boolean value that if "true" indicates that an event was processed.
*
* @throws NS_ERROR_UNEXPECTED
* Indicates that this method was erroneously called when this thread was
* not the current thread.
*/
boolean processNextEvent(in boolean mayWait);
/**
* Shutdown the thread asynchronously. This method immediately prevents
* further dispatch of events to the thread, and it causes any pending events
* to run to completion before this thread joins with the current thread.
*
* UNLIKE shutdown() this does not process events on the current thread.
* Instead it merely ensures that the current thread continues running until
* this thread has shut down.
*
* This method MAY NOT be executed from the thread itself. Instead, it is
* meant to be executed from another thread (usually the thread that created
* this thread or the main application thread). When this function returns,
* the thread will continue running until it exhausts its event queue.
*
* @throws NS_ERROR_UNEXPECTED
* Indicates that this method was erroneously called when this thread was
* the current thread, that this thread was not created with a call to
* nsIThreadManager::NewNamedThread, or that this method was called more
* than once on the thread object.
*/
void asyncShutdown();
/**
* Like `asyncShutdown`, but also returns a nsIThreadShutdown instance to
* allow observing and controlling the thread's async shutdown progress.
*/
nsIThreadShutdown beginShutdown();
/**
* Dispatch an event to a specified queue for the thread. This function
* may be called from any thread, and it may be called re-entrantly.
* Most users should use the NS_Dispatch*() functions in nsThreadUtils instead
* of calling this directly.
*
* @param event
* The alreadyAddRefed<> event to dispatch.
* NOTE that the event will be leaked if it fails to dispatch.
* @param queue
* Which event priority queue this should be added to
*
* @throws NS_ERROR_INVALID_ARG
* Indicates that event is null.
* @throws NS_ERROR_UNEXPECTED
* Indicates that the thread is shutting down and has finished processing
* events, so this event would never run and has not been dispatched.
*/
[noscript] void dispatchToQueue(in alreadyAddRefed_nsIRunnable event,
in EventQueuePriority queue);
/**
* This is set to the end of the last 50+ms event that was executed on
* this thread (for MainThread only). Otherwise returns a null TimeStamp.
*/
[noscript] readonly attribute TimeStamp lastLongTaskEnd;
[noscript] readonly attribute TimeStamp lastLongNonIdleTaskEnd;
/**
* Get information on the timing of the currently-running event.
*
* @param delay
* The amount of time the current running event in the specified queue waited
* to run. Will return TimeDuration() if the queue is empty or has not run any
* new events since event delay monitoring started. NOTE: delay will be
* TimeDuration() if this thread uses a PrioritizedEventQueue (i.e. MainThread)
* and the event priority is below Input.
* @param start
* The time the currently running event began to run, or TimeStamp() if no
* event is running.
*/
[noscript] void getRunningEventDelay(out TimeDuration delay, out TimeStamp start);
/**
* Set information on the timing of the currently-running event.
* Overrides the values returned by getRunningEventDelay
*
* @param delay
* Delay the running event spent in queues, or TimeDuration() if
* there's no running event.
* @param start
* The time the currently running event began to run, or TimeStamp() if no
* event is running.
*/
[noscript] void setRunningEventDelay(in TimeDuration delay, in TimeStamp start);
/**
* Set the QoS priority of threads where this may be available. Currently
* restricted to MacOS. Must be on the thread to call this method.
*
* @param aPriority
* The specified priority we will adjust to. Can be low (background) or
* normal (default / user-interactive)
*/
[noscript] void setThreadQoS(in nsIThread_QoSPriority aPriority);
};