| // Copyright 2016 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. |
| |
| #ifndef CONTENT_BROWSER_APPCACHE_APPCACHE_NAVIGATION_HANDLE_H_ |
| #define CONTENT_BROWSER_APPCACHE_APPCACHE_NAVIGATION_HANDLE_H_ |
| |
| #include <memory> |
| #include "base/macros.h" |
| |
| namespace content { |
| |
| class AppCacheNavigationHandleCore; |
| class ChromeAppCacheService; |
| |
| // This class is used to manage the lifetime of AppCacheHosts created during |
| // navigation. This is a UI thread class, with a pendant class on the IO |
| // thread, the AppCacheNavigationHandleCore. |
| // |
| // The lifetime of the AppCacheNavigationHandle, the |
| // AppCacheNavigationHandleCore and the AppCacheHost are the following : |
| // 1) We create a AppCacheNavigationHandle on the UI thread with a |
| // app cache host id of -1. This also leads to the creation of a |
| // AppCacheNavigationHandleCore with an id of -1. Every time |
| // an AppCacheNavigationHandle instance is created the global host id is |
| // decremented by 1. |
| // |
| // 2) When the navigation request is sent to the IO thread, we include a |
| // pointer to the AppCacheNavigationHandleCore. |
| // |
| // 3) The AppCacheHost instance is created and its ownership is passed to the |
| // AppCacheNavigationHandleCore instance. |
| // |
| // 4) When the navigation is ready to commit, the NavigationRequest will |
| // update the CommitNavigationParams based on the id from the |
| // AppCacheNavigationHandle. |
| // |
| // 5) The commit leads to AppCache registrations happening from the renderer. |
| // This is via the AppCacheBackend.RegisterHost mojo call. The |
| // AppCacheBackendImpl class which handles these calls will be informed |
| // about these hosts when the navigation commits. It will ignore the |
| // host registrations as they have already been registered. The |
| // ownership of the AppCacheHost is passed from the |
| // AppCacheNavigationHandle core to the AppCacheBackendImpl. |
| // |
| // 6) Meanwhile, RenderFrameHostImpl takes ownership of |
| // AppCacheNavigationHandle once navigation commits, so that precreated |
| // AppCacheHost is not destroyed before IPC above reaches AppCacheBackend. |
| // |
| // 7) When the next navigation commits, previous AppCacheNavigationHandle is |
| // destroyed. The destructor of the AppCacheNavigationHandle posts a |
| // task to destroy the AppCacheNavigationHandleCore on the IO thread. |
| |
| class AppCacheNavigationHandle { |
| public: |
| AppCacheNavigationHandle(ChromeAppCacheService* appcache_service, |
| int process_id); |
| ~AppCacheNavigationHandle(); |
| |
| int appcache_host_id() const { return appcache_host_id_; } |
| AppCacheNavigationHandleCore* core() const { return core_.get(); } |
| |
| // Called by NavigationHandleImpl::ReadyToCommitNavigation, because this is |
| // the earliest time when the process id is known. NavigationHandleImpl needs |
| // to construct AppCacheNavigationHandle at the start of a navigation (when |
| // the final process might not be known yet) and therefore temporarily |
| // constructs AppCacheNavigationHandle with an invalid process id. |
| // |
| // SetProcessId may only be called once, and only if kInvalidUniqueID was |
| // passed to the AppCacheNavigationHandle's constructor. |
| void SetProcessId(int process_id); |
| |
| private: |
| const int appcache_host_id_; |
| std::unique_ptr<AppCacheNavigationHandleCore> core_; |
| |
| DISALLOW_COPY_AND_ASSIGN(AppCacheNavigationHandle); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_APPCACHE_APPCACHE_NAVIGATION_HANDLE_H_ |