| // Copyright 2015 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. |
| |
| #include "chrome/browser/data_usage/tab_id_provider.h" |
| |
| #include <memory> |
| #include <vector> |
| |
| #include "base/bind.h" |
| #include "base/callback.h" |
| #include "base/location.h" |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/single_thread_task_runner.h" |
| #include "base/task_runner.h" |
| #include "base/task_runner_util.h" |
| |
| namespace chrome_browser_data_usage { |
| |
| namespace { |
| |
| // Convenience typedefs for clarity. |
| typedef base::OnceCallback<SessionID(void)> TabIdGetter; |
| typedef base::OnceCallback<void(SessionID)> TabIdCallback; |
| |
| // Temporary workaround because base::PostTaskAndReplyWithResult() does not |
| // support types without a default constructor. |
| // TODO(crbug.com/823798): Revert once a default constructor is reintroduced. |
| SessionID::id_type WrapTabIdGetter(TabIdGetter tab_id_getter) { |
| return std::move(tab_id_getter).Run().id(); |
| } |
| |
| } // namespace |
| |
| // Object that can run a list of callbacks that take tab IDs. New callbacks |
| // can only be added before it starts running the callbacks. Callbacks added |
| // will each be run exactly once. |
| class TabIdProvider::CallbackRunner { |
| public: |
| CallbackRunner() : is_done_(false), weak_ptr_factory_(this) {} |
| |
| // Adds a new callback to be run later. New callbacks must not be added after |
| // RunAll has been called, since they will never be run, as RunAll() is only |
| // ever called once. |
| void AddCallback(TabIdCallback callback) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(!is_done_); |
| callbacks_.push_back(std::move(callback)); |
| } |
| |
| // Runs all the callbacks in the order that they were added. This method must |
| // not be called more than once. |
| void RunAll(SessionID::id_type tab_info_value) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(!is_done_); |
| is_done_ = true; |
| |
| std::vector<TabIdCallback> running_callbacks; |
| running_callbacks.swap(callbacks_); |
| |
| SessionID tab_info = SessionID::FromSerializedValue(tab_info_value); |
| for (auto& callback : running_callbacks) |
| std::move(callback).Run(tab_info); |
| } |
| |
| base::WeakPtr<CallbackRunner> GetWeakPtr() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return weak_ptr_factory_.GetWeakPtr(); |
| } |
| |
| private: |
| base::ThreadChecker thread_checker_; |
| bool is_done_; |
| std::vector<TabIdCallback> callbacks_; |
| base::WeakPtrFactory<CallbackRunner> weak_ptr_factory_; |
| |
| DISALLOW_COPY_AND_ASSIGN(CallbackRunner); |
| }; |
| |
| TabIdProvider::TabIdProvider(base::TaskRunner* task_runner, |
| const base::Location& from_here, |
| TabIdGetter tab_id_getter) |
| : weak_ptr_factory_(this) { |
| std::unique_ptr<CallbackRunner> callback_runner(new CallbackRunner()); |
| weak_callback_runner_ = callback_runner->GetWeakPtr(); |
| callback_runner->AddCallback( |
| base::BindOnce(&TabIdProvider::OnTabIdReady, GetWeakPtr())); |
| |
| // The posted task takes ownership of |callback_runner|. If the task fails to |
| // be posted, then the destructor of |callback_runner| will pass a tab ID of |
| // -1 to OnTabIdReady, so that case doesn't need to be explicitly handled |
| // here. |
| base::PostTaskAndReplyWithResult( |
| task_runner, from_here, |
| base::BindOnce(&WrapTabIdGetter, std::move(tab_id_getter)), |
| base::BindOnce(&CallbackRunner::RunAll, |
| base::Owned(callback_runner.release()))); |
| } |
| |
| TabIdProvider::~TabIdProvider() {} |
| |
| void TabIdProvider::ProvideTabId(TabIdCallback callback) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| if (tab_info_.has_value()) { |
| std::move(callback).Run(*tab_info_); |
| return; |
| } |
| if (weak_callback_runner_) { |
| weak_callback_runner_->AddCallback(std::move(callback)); |
| return; |
| } |
| // If no cached tab ID is available and |weak_callback_runner_| has been |
| // destroyed, pass an invalid tab ID to the callback indicating that no tab |
| // was found. |
| std::move(callback).Run(SessionID::InvalidValue()); |
| } |
| |
| base::WeakPtr<TabIdProvider> TabIdProvider::GetWeakPtr() { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| return weak_ptr_factory_.GetWeakPtr(); |
| } |
| |
| // static |
| const void* const TabIdProvider::kTabIdProviderUserDataKey = |
| "TabIdProviderUserDataKey"; |
| |
| void TabIdProvider::OnTabIdReady(SessionID tab_info) { |
| DCHECK(thread_checker_.CalledOnValidThread()); |
| DCHECK(!tab_info_.has_value()); |
| |
| tab_info_ = tab_info; |
| } |
| |
| } // namespace chrome_browser_data_usage |