third_party/WebKit/Source/core/workers/InProcessWorkerMessagingProxy.cpp

/*
 * Copyright (C) 2008 Apple Inc. All Rights Reserved.
 * Copyright (C) 2009 Google Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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#include "core/workers/InProcessWorkerMessagingProxy.h"

#include "core/dom/ExecutionContextTask.h"
#include "core/dom/SecurityContext.h"
#include "core/events/ErrorEvent.h"
#include "core/events/MessageEvent.h"
#include "core/frame/LocalFrame.h"
#include "core/frame/csp/ContentSecurityPolicy.h"
#include "core/loader/DocumentLoadTiming.h"
#include "core/loader/DocumentLoader.h"
#include "core/origin_trials/OriginTrialContext.h"
#include "core/workers/InProcessWorkerBase.h"
#include "core/workers/InProcessWorkerObjectProxy.h"
#include "core/workers/WorkerClients.h"
#include "core/workers/WorkerGlobalScope.h"
#include "core/workers/WorkerInspectorProxy.h"
#include "core/workers/WorkerThreadStartupData.h"
#include "public/platform/WebTaskRunner.h"
#include "wtf/WTF.h"
#include <memory>

namespace blink {

namespace {

void processUnhandledExceptionOnWorkerGlobalScope(int exceptionId, ExecutionContext* scriptContext)
{
    WorkerGlobalScope* globalScope = toWorkerGlobalScope(scriptContext);
    globalScope->exceptionUnhandled(exceptionId);
}

void processMessageOnWorkerGlobalScope(PassRefPtr<SerializedScriptValue> message, std::unique_ptr<MessagePortChannelArray> channels, InProcessWorkerObjectProxy* workerObjectProxy, ExecutionContext* scriptContext)
{
    WorkerGlobalScope* globalScope = toWorkerGlobalScope(scriptContext);
    MessagePortArray* ports = MessagePort::entanglePorts(*scriptContext, std::move(channels));
    globalScope->dispatchEvent(MessageEvent::create(ports, std::move(message)));
    workerObjectProxy->confirmMessageFromWorkerObject();
    workerObjectProxy->startPendingActivityTimer();
}

} // namespace

InProcessWorkerMessagingProxy::InProcessWorkerMessagingProxy(InProcessWorkerBase* workerObject, WorkerClients* workerClients)
    : InProcessWorkerMessagingProxy(workerObject->getExecutionContext(), workerObject, workerClients)
{
    DCHECK(m_workerObject);
}

InProcessWorkerMessagingProxy::InProcessWorkerMessagingProxy(ExecutionContext* executionContext, InProcessWorkerBase* workerObject, WorkerClients* workerClients)
    : ThreadedMessagingProxyBase(executionContext)
    , m_workerObjectProxy(InProcessWorkerObjectProxy::create(this))
    , m_workerObject(workerObject)
    , m_workerClients(workerClients)
    , m_unconfirmedMessageCount(0)
    , m_workerGlobalScopeMayHavePendingActivity(false)
{
}

InProcessWorkerMessagingProxy::~InProcessWorkerMessagingProxy()
{
    DCHECK(!m_workerObject);
}

void InProcessWorkerMessagingProxy::startWorkerGlobalScope(const KURL& scriptURL, const String& userAgent, const String& sourceCode)
{
    DCHECK(isParentContextThread());
    if (askedToTerminate()) {
        // Worker.terminate() could be called from JS before the thread was
        // created.
        return;
    }

    Document* document = toDocument(getExecutionContext());
    SecurityOrigin* starterOrigin = document->getSecurityOrigin();

    ContentSecurityPolicy* csp = m_workerObject->contentSecurityPolicy() ? m_workerObject->contentSecurityPolicy() : document->contentSecurityPolicy();
    DCHECK(csp);

    WorkerThreadStartMode startMode = workerInspectorProxy()->workerStartMode(document);
    std::unique_ptr<WorkerSettings> workerSettings = wrapUnique(new WorkerSettings(document->settings()));
    std::unique_ptr<WorkerThreadStartupData> startupData = WorkerThreadStartupData::create(scriptURL, userAgent, sourceCode, nullptr, startMode, csp->headers().get(), m_workerObject->referrerPolicy(), starterOrigin, m_workerClients.release(), document->addressSpace(), OriginTrialContext::getTokens(document).get(), std::move(workerSettings));

    initializeWorkerThread(std::move(startupData));
    workerInspectorProxy()->workerThreadCreated(document, workerThread(), scriptURL);
}

void InProcessWorkerMessagingProxy::postMessageToWorkerObject(PassRefPtr<SerializedScriptValue> message, std::unique_ptr<MessagePortChannelArray> channels)
{
    DCHECK(isParentContextThread());
    if (!m_workerObject || askedToTerminate())
        return;

    MessagePortArray* ports = MessagePort::entanglePorts(*getExecutionContext(), std::move(channels));
    m_workerObject->dispatchEvent(MessageEvent::create(ports, std::move(message)));
}

void InProcessWorkerMessagingProxy::postMessageToWorkerGlobalScope(PassRefPtr<SerializedScriptValue> message, std::unique_ptr<MessagePortChannelArray> channels)
{
    DCHECK(isParentContextThread());
    if (askedToTerminate())
        return;

    std::unique_ptr<ExecutionContextTask> task = createCrossThreadTask(&processMessageOnWorkerGlobalScope, message, passed(std::move(channels)), crossThreadUnretained(&workerObjectProxy()));
    if (workerThread()) {
        // A message event is an activity and may initiate another activity.
        m_workerGlobalScopeMayHavePendingActivity = true;
        ++m_unconfirmedMessageCount;
        workerThread()->postTask(BLINK_FROM_HERE, std::move(task));
    } else {
        m_queuedEarlyTasks.append(std::move(task));
    }
}

void InProcessWorkerMessagingProxy::dispatchErrorEvent(const String& errorMessage, std::unique_ptr<SourceLocation> location, int exceptionId)
{
    DCHECK(isParentContextThread());
    if (!m_workerObject)
        return;

    // We don't bother checking the askedToTerminate() flag here, because
    // exceptions should *always* be reported even if the thread is terminated.
    // This is intentionally different than the behavior in MessageWorkerTask,
    // because terminated workers no longer deliver messages (section 4.6 of the
    // WebWorker spec), but they do report exceptions.

    ErrorEvent* event = ErrorEvent::create(errorMessage, location->clone(), nullptr);
    if (m_workerObject->dispatchEvent(event) == DispatchEventResult::NotCanceled)
        postTaskToWorkerGlobalScope(BLINK_FROM_HERE, createCrossThreadTask(&processUnhandledExceptionOnWorkerGlobalScope, exceptionId));
}

void InProcessWorkerMessagingProxy::workerThreadCreated()
{
    ThreadedMessagingProxyBase::workerThreadCreated();

    DCHECK(isParentContextThread());

    DCHECK(!m_unconfirmedMessageCount);
    m_unconfirmedMessageCount = m_queuedEarlyTasks.size();

    // Worker initialization means a pending activity.
    m_workerGlobalScopeMayHavePendingActivity = true;

    for (auto& earlyTask : m_queuedEarlyTasks)
        workerThread()->postTask(BLINK_FROM_HERE, std::move(earlyTask));
    m_queuedEarlyTasks.clear();
}

void InProcessWorkerMessagingProxy::parentObjectDestroyed()
{
    DCHECK(isParentContextThread());

    // parentObjectDestroyed() is called in InProcessWorkerBase's destructor.
    // Thus it should be guaranteed that a weak pointer m_workerObject has been
    // cleared before this method gets called.
    DCHECK(!m_workerObject);

    ThreadedMessagingProxyBase::parentObjectDestroyed();
}

void InProcessWorkerMessagingProxy::confirmMessageFromWorkerObject()
{
    DCHECK(isParentContextThread());
    if (askedToTerminate())
        return;
    DCHECK(m_unconfirmedMessageCount);
    --m_unconfirmedMessageCount;
}

void InProcessWorkerMessagingProxy::pendingActivityFinished()
{
    DCHECK(isParentContextThread());
    DCHECK(m_workerGlobalScopeMayHavePendingActivity);
    if (m_unconfirmedMessageCount > 0) {
        // Ignore the report because an inflight message event may initiate a
        // new activity.
        return;
    }
    m_workerGlobalScopeMayHavePendingActivity = false;
}

bool InProcessWorkerMessagingProxy::hasPendingActivity() const
{
    DCHECK(isParentContextThread());
    if (askedToTerminate())
        return false;
    return m_unconfirmedMessageCount || m_workerGlobalScopeMayHavePendingActivity;
}

} // namespace blink