1731495 - xdg-desktop-portal 1.10.0 breaks pipewire support

Status: RESOLVED FIXED

(Core :: WebRTC, defect)

Description

[Jan Alexander Steffens [:heftig]]

See a fix for this issue in OBS: https://github.com/obsproject/obs-studio/commit/ef0540c0d7df64b6cb148c80d566281a4ff3ba5c

In the response for the session create request, the type for the "session_handle" field was changed from "s" to "o" to match the documentation. Unfortunately, this now causes clients that do typechecks to fail.

Comment 1

[Jan Alexander Steffens [:heftig]]

Attachment: Bug 1731495 - Don't typecheck the pipewire session_handle. r?rmader

Since xdg-desktop-portal 1.10.0, the type is "o" (an object path string)
instead of "s" (a normal string). g_variant_lookup fails if the type
doesn't match exactly, even though both are strings.

Use g_variant_lookup_value to get the field value, telling it not to
typecheck. Use g_variant_dup_string to extract the string, which doesn't
care about the exact type, so this code should work with all versions of
xdg-desktop-portal.

Following a similar fix to OBS, see
https://github.com/obsproject/obs-studio/commit/ef0540c0d7df.

Comment 2

[Robert Mader [:rmader]]

Try: https://treeherder.mozilla.org/jobs?repo=try&revision=47bde78942bc38fcb3d517680d718590ac31447e

Comment 3

[Robert Mader [:rmader]]

Upstream MR: https://webrtc-review.googlesource.com/c/src/+/232329 (but that's not allowed URL for a see-also...).

Comment 4

[Jan Alexander Steffens [:heftig]]

Try build WFM, xdg-desktop-portal 1.10.0, Arch Linux.

Comment 5

[Robert Mader [:rmader]]

Martin, you may want to forward port this on Fedora >=35

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/21f27a8573cb
Don't typecheck the pipewire session_handle. r=rmader

Comment 8

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/21f27a8573cb

Comment 9

[Teoh Han Hui]

Could this be backported? It'll break screen sharing for many of us on Wayland sessions. Not updating xdg-desktop-portal is not a realistic workaround on a rolling release distro.

Comment 10

[Robert Mader [:rmader]]

Comment on attachment 9241975 [details]
Bug 1731495 - Don't typecheck the pipewire session_handle. r?rmader

Beta/Release Uplift Approval Request

• User impact if declined: Users with a recent version of xdg-desktop-portal (Arch, beta versions of Fedora or Ubuntu) will have broken screen sharing on Wayland.
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Only Wayland screen sharing is affected, equivalent patches are used in other software such as upstream Chrome and OBS Studio.
• String changes made/needed:

Comment 11

[Pascal Chevrel:pascalc (PTO until April 26)]

Comment on attachment 9241975 [details]
Bug 1731495 - Don't typecheck the pipewire session_handle. r?rmader

The impact is important for the users affected and we don't officially ship Wayland ourselves so that seems not risky, approved for 93 beta 8, thanks.

Comment 12

[Pascal Chevrel:pascalc (PTO until April 26)]

https://hg.mozilla.org/releases/mozilla-beta/rev/dda8fae34117

Comment 13

[Martin Stránský [:stransky] (ni? me)]

Thanks, I think 93 is fine.