Write access to the shared memory region is required because JavaScript lacks
the capability to create read-only ArrayBuffers. When a user attempts to modify
an ArrayBuffer that utilizes a ReadOnlySharedMemoryRegion as its BackingStore
it triggers an access violation.
Note that this pull request may be reverted in the future if JavaScript adds
read-only ArrayBuffer support.
The CefFrame::CreateURLRequest method is no longer supported in the renderer
process. Usage of this method was already limited to same-origin requests due
to renderer process CORS restrictions, and the underlying Blink API has now
been removed in https://crbug.com/1413912 (M112+).
Existing alternatives include CefURLRequest usage in the browser process, or
JavaScript XMLHttpRequest/fetch API usage in the renderer process.
Send a FrameDetached message from CefFrameHostImpl::Detach before closing
the RenderFrame connection to avoid an immediate reconnect attempt by the
renderer.
When BFCache is disabled the intentionally detached frame will never be
reconnected. When BFCache is enabled the intentionally detached frame will
be reconnected via CefFrameImpl::OnWasShown if/when it exits the cache.
Run with "--vmodule=frame_*=1 --enable-logging=stderr --no-sandbox" on the
command-line to see these log messages from both the browser and renderer
processes.
CefSharedProcessMessageBuilder supports creation of a CefProcessMessage
backed by a CefSharedMemoryRegion.
Performance tests comparing the existing ArgumentList approach and the new
SharedMemoryRegion approach have been added to cefclient at
http://tests/ipc_performance.
CefMessageRouter has been updated to use SharedMemoryRegion as transport
for larger message payloads. The threshold is configurable via
|CefMessageRouterConfig.message_size_threshold|.
To test:
run `ceftests --gtest_filter=SendSharedProcessMessageTest.*:SharedProcessMessageTest.*:MessageRouterTest.Threshold*`
When bfcache is disabled use the RenderFrameObserver::DidFinishLoad notification
instead of the DidStopLoading notification that originates from the browser
process. During fast navigation the DidStopLoading notification may arrive in
the renderer after a new navigation has commenced and cause the wrong regions to
be reported.
- Windows: SDK version 10.0.20348.0 is now required.
- MacOS: SDK version 12.3 (Xcode 13.3) is now required.
- Legacy swiftshader binaries (`swiftshader/*` on Win/Linux and
`libswiftshader_*.dylib` on MacOS) have been removed (see issue #3176).
With same-site BFCache enabled every navigation can now potentially be served
via the BFCache. To support this internally a new top-level RenderFrame object
may be created for each new navigation. As a result, OnBrowserCreated may now
be called multiple times with the same browser ID in a given renderer process
(a behavior previously only seen with cross-site navigations and different
renderer processes).
BFCache navigations do not trigger the same Chromium notifications as a normal
load. To avoid breaking CEF API usage expectations we now synthetically
generate the load-related callbacks that would otherwise be missing
(OnLoadingStateChange with isLoading=true, OnLoadStart, OnLoadEnd). The
|httpStatusCode| argument to OnLoadEnd will be 0 in this case.
To test:
- Run `FrameHandlerTest.*:MessageRouterTest.*:NavigationTest.*`
- Run `NavigationTest.LoadSameOriginLoadURL` for OnBrowserCreated behavior.
- Run `NavigationTest.History` for load-related callback behavior.
The mojo channel used for frame communication may disconnect for a variety of
reasons including frame navigation, frame destruction, or insertion into the
BackForwardCache (when the browser-side frame representation is destroyed and
closes the connection). When disconnect occurs we now evaluate the situation
and reconnect if appropriate.
Connections are now initiated solely from the renderer process and the
RenderFrame is passed as an argument to FrameAttached() instead of being
retrieved independently. Messages are queued while the frame is disconnected
and sent only after FrameAttachedAck() is received from the browser process.
The renderer process will be crashed intentionally with a "connection retry
failure" message if the reconnect fails 3 times in a row.
With PdfUnseasoned the PDF file will be loaded in a dedicated renderer process.
We identify this process by adding the kPdfRenderer command-line flag (similar
to how kExtensionProcess is used to identify an extension renderer process). We
then avoid calling GetNewBrowserInfo for the PDF renderer process because we
know the request will otherwise time out.
- Remove CefRequestContextHandler::OnBeforePluginLoad and
CefRequestContext::PurgePluginListCache (fixes issue #3047). These methods
stopped being relevant after the removal of Flash support in January 2021.
The last remaining PPAPI plugin (PDF viewer) will switch to a non-plugin
implementation in the near future (see https://crbug.com/702993#c58) and
functionality related to plugin filtering has already been removed in
https://crrev.com/343ae351c9.
When BackForwardCache is enabled and the user navigates the main frame
back/forward a new RFH may be created for an existing main frame GlobalId value
and CefFrameHostImpl (e.g. an object that was previously Detach()ed after main
frame navigation called SetMainFrame, but for which RenderFrameDeleted was not
subsequently called due to insertion in the BackForwardCache). In this case we
can re-attach the new RFH to the existing main frame CefFrameHostImpl in
RenderFrameHostStateChanged and resume processing of messages.
Swapping back/forward to an existing (already loaded) renderer does not trigger
new notifications for draggable regions (e.g. RenderFrameObserver::
DraggableRegionsChanged is not called by default). We therefore explicitly
request an update of draggable regions by sending the DidStopLoading message to
the renderer.
A new |reattached| parameter is added to CefFrameHandler::OnFrameAttached to
support identification of BackForwardCache usage by the client.
To test with unit tests:
Run `ceftests --gtest_filter=DraggableRegionsTest.DraggableRegionsCrossOrigin
--enable-features=BackForwardCache`
To test manually:
1. Run `cefclient --enable-features=BackForwardCache --use-views
--url=http://tests/draggable`, note that draggable regions work.
2. Load https://www.google.com via the address bar, note that draggable regions
are removed.
3. Go back to http://tests/draggable, note that draggable regions work.
4. Go forward to https://www.google.com, note that draggable regions are
removed.
When CefApp::GetRenderProcessHandler returned null
CefRenderFrameObserver::DidCreateScriptContext was returning early (not
calling CefFrameImpl::OnContextCreated) and consequently queued actions
such as JavaScript were never executed.