On Fri, Jan 6, 2012 at 8:08 AM, Fady Samuel <[email protected]> wrote: > Your diagram is a start. I don't recall all my layering violation confusions > but the latest confusion I had was in regards to what goes in the > Source/WebCore/platform directory? > > Why are things like ScrollView ScrollableArea, Timer, or even NotImplemented > or Length in that directory? A lot of these things don't look like > platform-specific code.
Platform isn't about platform-specific code. It's an abstraction of the platform upon which WebCore runs. Code generally goes there because it's not specific to a web rendering engine (e.g., it doesn't refer to DOM or CSS concepts) but it's not something that would be used by every program (e.g., RefPtr). > They're also not necessarily interfaces to > platform-specific code. So what are they? How does one decide something > belongs in Source/WebCore/platform. Something should go into Platform if it's an abstraction of a facility provided by the underlying platform. For example, ScrollableArea is an abstraction of a concept provided by most platforms. Something should not go in Platform if it refers to web concepts (e.g., a Frame, which belongs in WebCore proper) or if it's something that might be used by every program (e.g., RefPtr, which belongs in WTF). > What can things in this directory depend on and what can they not depend on? That's described by the diagram earlier in this thread. Platform can depend on third-party libraries (e.g., SQLite) or on operating system facilities. Platform can depend on WTF, but no other code in the WebKit project. Adam > On Thu, Jan 5, 2012 at 7:39 PM, Adam Barth <[email protected]> wrote: >> >> On Thu, Jan 5, 2012 at 4:18 PM, Fady Samuel <[email protected]> wrote: >> > I've been working on WebKit off and on for a while now but I must admit >> > that, up to this point, I still don't have a firm grasp of all the >> > layering >> > in WebKit. What depends on what, and what cannot depend on what? What is >> > the >> > motivation of each of these individual layers? I understand the need to >> > have >> > WebKit supported under multiple platforms and with any embedder, and but >> > I >> > often don't fully understand what constitues a layering violation or >> > why. >> > >> > Could someone please summarize or provide a link that explains all this? >> > I >> > think this would be beneficial to the entire WebKit community! >> >> There's one diagram: >> >> >> https://docs.google.com/drawings/d/10WlCj2J3arxf4cDGRKteNinaP755iFnmYtYtnNSCQOY/edit?authkey=CP6plYAI&hl=en_US >> >> It's not perfectly accurate because it's something of a proposal, but >> it should give you a high-level view. Do you have specific questions? >> I'm happy to draw more pictures if that would be helpful. >> >> Adam > > _______________________________________________ webkit-dev mailing list [email protected] http://lists.webkit.org/mailman/listinfo.cgi/webkit-dev
