1097953 - Combine PluginWidgetChild and PluginWidgetProxy

Status: RESOLVED INCOMPLETE

(Core Graveyard :: Plug-ins, defect)

Description

[Jim Mathies [:jimm]]

These two have different lifetimes, but billm assures me nsISupports and ipdl can live together harmoniously if ipdl uses ref counting in its management.

This is a non-blocking e10s bug, probably would make a good first bug too.

Comment 1

[Benjamin Smedberg]

I really hate reference-counted IPDL objects, see bug 1096536 for a discussion. My opinion is that it's pretty much always better to have separate refcounted and IPDL objects.

billm do you disagree?

Comment 2

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

In my opinion, the problem of having IPDL actors whose lifetimes aren't a good match for IPDL won't go away. If we tell people to use separate objects, then we'll just have a different problem where people create two objects that point to each other. When people forget to clear these pointers at the right times, they'll create use-after-free errors.

I think IPDL needs to manage this stuff itself. It seems easier to manage if it's all done in one object, but I'm sure there's a way to do it with two objects too.

Comment 3

[Benjamin Smedberg]

I am much less worried about UAF errors: because IPDL has explicit shutdown machinery with ActorDestroy, there is well-known place to do that cleanup, and the null checks that might be required are more obvious when writing and reviewing code.

Comment 4

[Benjamin Smedberg]

Resolving old bugs which are likely not relevant any more, since NPAPI plugins are deprecated.