September 2024 - webkit-dev - lists.webkit.org

InjectedBundle deprecation
by Alex Christensen 01 Aug '25

01 Aug '25

Hello WebKit developers! We are ramping up to do some serious work on Site Isolation which includes putting cross-origin iframes in a different process than the parent frame. Similar efforts have been done in other browser engines and some related work has already been done in WebKit, but not enough. This will do strange things to the InjectedBundle APIs, which have fundamental assumptions that the whole DOM is in one process and that communication only happens with one process at a time. We have never exposed InjectedBundle APIs as public API, but some other distributors of WebKit have. As we make progress on this project, we anticipate that anything in Source/WebKit/WebProcess/InjectedBundle/API is subject to deprecation and removal. This will also allow us to tighten the sandbox on the web process, resolve security and performance issues, and have cleaner code. Would the maintainers of the GTK and WPE APIs be willing to assist in migrating from those APIs and designing replacements in the UI process? Alex Christensen

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Site isolation
by Alex Christensen 01 Aug '25

01 Aug '25

The SiteIsolation feature is beginning to work in the simplest of cases, but I had to do some work in the Source/WebKit/Shared/RemoteLayerTree directory, which is platform-specific. Basically all the use of LayerHostingContextIdentifier in that directory needs an equivalent implementation for other graphics implementations, like in the CoordinatedGraphics directories. There is one layout test in LayoutTests/http/tests/site-isolation/basic-iframe.html that is currently skipped on all non-Cocoa platforms. Is someone willing to collaborate to design and implement the feature in non-Cocoa ports? We are in the early stages of the project and have a long way to go, so I imagine things will continue to come up, like deciding how to implement event handling and other platform dependent features. Alex

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Site isolation platform code
by Alex Christensen 14 Jan '25

14 Jan '25

Hey everyone! I’ve been doing a bunch of work on site isolation recently, and I’ve been doing my best to make all my changes platform-independent so it just works for everyone. However, there are two places I could use some collaboration with other WebKit developers: 1. createNewPage in WebKitUIClient.cpp needs some hooking up of the API::PageConfiguration in a way I couldn’t figure out in the few minutes I looked at it. This should be pretty straightforward to someone who knows the glib code better than I do. 2. We have a growing number of tests in LayoutTests/http/tests/site-isolation that exercise drawing code, which will take a significant amount of work to get implemented on non-Cocoa platforms. A lot of changes are happening in this area right now with the adoption of Skia, and it would be great if it were done in a way that could support site isolation. Thanks, Alex

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Proposal: bundled/vendored code belongs under ThirdParty/
by Michael Catanzaro 07 Oct '24

07 Oct '24

Hi developers, I request that bundled or "vendored" sources copied from other upstream projects should live under a directory named "ThirdParty" so we can keep track of it. Not knowing about bundled sources causes various problems, e.g. we've previously shipped unused libavif and dav1d sources in WebCore due to not knowing about them. Ideally third-party code should be placed in Source/ThirdParty. If the requirements of Apple's internal build system do not allow for putting the code in Source/ThirdParty, then you can create a new ThirdParty directory wherever needed, e.g. Source/WebCore/PAL/ThirdParty. Currently we have at least wtf/simde and wtf/simdutf violating these guidelines. If somebody with XCode could please create a wtf/ThirdParty and move the directories to there, that would be helpful. Unfortunately it's not easy to move sources without XCode. If you know of other bundled sources elsewhere in WebKit, let's do the similar moves for those as well. (This rule doesn't need to apply for minimal one-time copying, like taking just a useful file or two from an upstream project and incorporating it into WebKit. Of course that is fine. We just shouldn't have entire upstream projects hidden in WebKit.) Thanks, Michael

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Initializing member variables
by Ryosuke Niwa 03 Oct '24

03 Oct '24

Should we do: struct Foo { int bar = 0; } Or struct Foo { int bar { 0 }; } We do both at the moment. - R. Niwa

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Naming singletons
by Ryosuke Niwa 13 Sep '24

13 Sep '24

Hi all, TL; DR: Add “Singleton” suffix to a function which returns a singleton to help aid WebKit static analyzers. It’s fairly common for some classes to provide a static member function which returns a singleton. Such a function typically holds NeverDestroyed instance of an object and it’s safe to call any mutating member functions on it without locally storing Ref/RefPtr/CheckedRef/CheckedPtr. Unfortunately, this poses a challenge for WebKit static analyzers which enforces safe smart pointer usage because the static analyzers can’t differentiate a static function which returns a singleton and a static function which returns a non-singleton instance of an object. For this reason, I suggest we start suffixing the name of each function which returns a singleton with “Singleton” e.g. IOSurfacePool::sharedPoolSingleton instead of IOSurfacePool::sharedPool. This will help aid static analyzers to identify a function which returns a singleton and not generate superfluous warnings for it. - R. Niwa

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Obtaining backtraces
by Michael Orlitzky 08 Sep '24

08 Sep '24

I spent the entire day today figuring out how to get a backtrace from the installed copy of webkit-gtk. But I don't _just_ want to complain. I'd like to figure out a way to do this easily, and to update the documentation. The existing docs, https://trac.webkit.org/wiki/WebKitGTK/Debugging are pretty misleading: * Core dumps don't happen any more because of bubblewrap * WEBKIT2_PAUSE_WEB_PROCESS_ON_LAUNCH quietly does nothing unless you happen to have built with DEVELOPER_MODE (won't be the case on a linux distro) * The minibrowser isn't going to be available on a distro, and if you aren't using the minibrowser, gdb won't follow the right children... * And you can't reliably guess the right PID of a running process quick enough to attach to it in e.g. epiphany. Rebuilding from a git checkout and hacking on the webkit source to enable DEVELOPER_MODE or the minibrowser is not always feasible. (Or desirable -- I want to debug the code that is actually crashing, and not spend three days guessing!) I've been dealing with crashes on my laptop for years because it has very little RAM -- it simply doesn't have the resources to build a development copy of webkit-gtk. Even now, on a system with 64 low-power cores, it still takes more than a day, and that's after spending half the day figuring out how to configure the build exactly like the distro does, so that you can reproduce the crash. So for starters: is there something I missed? Some easy way to get a traceback from a modern, system copy of webkit-gtk? One idea: how hard would it be to skip bubblewrap in a release build if some environment variable is set?

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2024 WebKit Contributors Meeting - Registration is Open!
by Jonathan Davis 04 Sep '24

04 Sep '24

Hello WebKit Contributors, You are invited to participate in the 2024 WebKit Contributors Meeting at the Hyatt House San Jose/Cupertino or online via WebEx on Tuesday, October 22nd and Wednesday, October 23rd. ## Registration ## To attend, you must be an active contributor to the WebKit open-source project. The meeting will be free of charge and registration is now open! Registration is required whether you are attending in-person or virtually. You can find more details about the event and register at the WebKit Contributors Meeting page: https://webkit.org/meeting/ ## Format ## As in past years, the event will feature presentation-led discussions of 10-40 minutes long, followed by Q&A discussions and significant breaks for discussions. There will also be a lightning talk segment if you have a topic to present that is 10 minutes or less. Please reach out to Jon Davis via email or WebKit Slack to reserve a spot for your presentation. ## Tentative Schedule ## *Tuesday, October 22nd* 9 AM Pacific to midday — Birds of a feather (self-organized, in-person) LUNCH Midday – 5pm Pacific — Formal presentations (in-person and online) *Thursday, October 17th* 9 AM Pacific to midday — Formal presentations (in-person and online) LUNCH Midday – 5pm Pacific — Birds of a feather (in-person) This schedule will be finalized to accommodate the presentations pitched. ## Health & Safety ## For the safety of everyone attending the meeting, in-person attendees will be required to wear a mask indoors except while actively eating and drinking. If you are feeling ill, we encourage you to join remotely using WebEx. We also strongly encourage testing for COVID prior to attending in-person and attending online if you receive any positive result. Feel free to submit ideas or questions about this year’s online event in the #contributors-meeting channel on WebKit Slack. We’re looking forward to seeing you there! --- Jon Davis, on behalf of the WebKit Contributors Meeting Organizers

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