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content / browser / renderer_host / keep_alive_handle_factory.cc [blame]
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/renderer_host/keep_alive_handle_factory.h"
#include <atomic>
#include <memory>
#include <utility>
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/public/browser/browser_task_traits.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_features.h"
#include "mojo/public/cpp/bindings/pending_receiver.h"
#include "mojo/public/cpp/bindings/unique_receiver_set.h"
#include "third_party/blink/public/mojom/loader/keep_alive_handle.mojom.h"
#include "third_party/blink/public/mojom/loader/keep_alive_handle_factory.mojom.h"
namespace content {
namespace {
std::atomic_uint64_t handle_sequence_id{0};
inline uint64_t GetNextHandleId() {
return handle_sequence_id.fetch_add(1, std::memory_order_relaxed);
}
class KeepAliveHandleImpl final : public blink::mojom::KeepAliveHandle {
public:
explicit KeepAliveHandleImpl(int process_id)
: process_id_(process_id), handle_id_(GetNextHandleId()) {
RenderProcessHost* process_host = RenderProcessHost::FromID(process_id_);
GetContentClient()->browser()->OnKeepaliveRequestStarted(
process_host ? process_host->GetBrowserContext() : nullptr);
if (!process_host || process_host->AreRefCountsDisabled()) {
return;
}
static_cast<RenderProcessHostImpl*>(process_host)
->IncrementKeepAliveRefCount(handle_id_);
}
~KeepAliveHandleImpl() override {
GetContentClient()->browser()->OnKeepaliveRequestFinished();
RenderProcessHost* process_host = RenderProcessHost::FromID(process_id_);
if (!process_host || process_host->AreRefCountsDisabled()) {
return;
}
static_cast<RenderProcessHostImpl*>(process_host)
->DecrementKeepAliveRefCount(handle_id_);
}
KeepAliveHandleImpl(const KeepAliveHandleImpl&) = delete;
KeepAliveHandleImpl& operator=(const KeepAliveHandleImpl&) = delete;
private:
const int process_id_;
// A unique identifier for this KeepAliveHandle that can be recorded in
// Increment/DecrementKeepAliveRefCount for debugging purposes.
// TODO(wjmaclean): Once we understand the root causes of
// https://crbug.com/1148542, we can remove this.
uint64_t handle_id_;
};
} // namespace
class KeepAliveHandleFactory::Context
: public blink::mojom::KeepAliveHandleFactory {
public:
explicit Context(int process_id) : process_id_(process_id) {}
Context(const Context&) = delete;
Context& operator=(const Context&) = delete;
~Context() override = default;
void IssueKeepAliveHandle(
mojo::PendingReceiver<blink::mojom::KeepAliveHandle> receiver) override {
handle_receivers_.Add(std::make_unique<KeepAliveHandleImpl>(process_id_),
std::move(receiver));
}
void Bind(
mojo::PendingReceiver<blink::mojom::KeepAliveHandleFactory> receiver) {
factory_receivers_.Add(this, std::move(receiver));
}
private:
mojo::UniqueReceiverSet<blink::mojom::KeepAliveHandle> handle_receivers_;
mojo::ReceiverSet<blink::mojom::KeepAliveHandleFactory> factory_receivers_;
const int process_id_;
};
KeepAliveHandleFactory::KeepAliveHandleFactory(RenderProcessHost* process_host,
base::TimeDelta timeout)
: context_(std::make_unique<Context>(process_host->GetID())),
timeout_(timeout) {}
KeepAliveHandleFactory::~KeepAliveHandleFactory() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
// Extend the lifetime of `context_` a bit. Note that `context_` has an
// ability to extend the lifetime of the associated render process.
GetUIThreadTaskRunner({})->PostDelayedTask(
FROM_HERE, base::DoNothingWithBoundArgs(std::move(context_)), timeout_);
}
void KeepAliveHandleFactory::Bind(
mojo::PendingReceiver<blink::mojom::KeepAliveHandleFactory> receiver) {
context_->Bind(std::move(receiver));
}
} // namespace content