1886937 - [UIA] Figure out how to block UIA instantiation with native UIA implementation

Status: RESOLVED FIXED

(Core :: Disability Access APIs, task)

Description

[James Teh [:Jamie]]

I hooked up our new native UIA implementation in bug 1886371. However, it bypasses LazyInstantiator and instantiates the a11y engine immediately because LazyInstantiator doesn't support UIA. We need to find some way to ensure that the a11y client block list still works.

Comment 1

[James Teh [:Jamie]]

I'm working on supporting UIA in LazyInstantiator. I have a working proof of concept locally that I need to polish up.

I originally thought i was going to need to block a bunch of QueryInterface calls, but it seems that's not necessary. However, since these IIDs can be tricky to find, just in case it's useful for future reference, here's the code I had:

static const GUID kUnsupportedInterfaces[] = {
  IID_IAccIdentity,
  // IRawElementProviderComponent
  { 0x62F62F5A, 0x5EC0, 0x48F5, {0xA0, 0x32, 0x78, 0x34, 0x45, 0xDF, 0x9A, 0x89}},
  // Unknown
  {0xA3D361A2, 0x2919, 0x42A1, {0xB3, 0xDD, 0x65, 0x95, 0xB4, 0x32, 0xF2, 0xDD}},
};
...
for (const GUID& unsupported: kUnsupportedInterfaces) {
  if (aIID == unsupported) {
    return E_NOINTERFACE;
  }
}

Comment 2

[James Teh [:Jamie]]

Attachment: Bug 1886937: Support UIA in LazyInstantiator.

This allows UIA client detection and blocking to work with the native UIA implementation.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0beadc50afd8
Support UIA in LazyInstantiator. r=nlapre

Comment 4

[tszentpeteri]

https://hg.mozilla.org/mozilla-central/rev/0beadc50afd8