[PATCH wayland] RFC: Require WAYLAND_DISPLAY to be set instead of using wayland-0 as the default
halfline at gmail.com
Fri Aug 14 08:22:55 PDT 2015
> thanks, and sorry I didn't see your reply before I pushed. :-D
So this commit totally broke gtk+.
Thread 1 (Thread 0x7f3813651980 (LWP 537)):
#0 g_logv (log_domain=0x7f38128b01ce "Gdk",
log_level=G_LOG_LEVEL_ERROR, format=<optimized out>, args=<optimized
#1 0x00007f380edd30cd in wl_log (fmt=fmt at entry=0x7f380edd31b8 "error:
WAYLAND_DISPLAY not set in the environment.\n")
#2 0x00007f380edd0115 in connect_to_socket (name=0x0) at
#3 wl_display_connect (name=name at entry=0x0) at ../src/wayland-client.c:899
#4 0x00007f38128a5f7e in _gdk_wayland_display_open (display_name=0x0)
#5 0x00007f381285b357 in gdk_display_manager_open_display
(manager=<optimized out>, name=0x0)
#6 0x00007f3812d24c10 in gtk_init_check (argc=<optimized out>,
argv=<optimized out>) at ../../gtk/gtkmain.c:1011
#7 0x00007f3812d24c49 in gtk_init (argc=<optimized out>,
argv=<optimized out>) at ../../gtk/gtkmain.c:1068
#8 0x0000000000400e11 in main (argc=0, argv=0x0) at
gtk+ treats wl_log messages as fatal errors. See this commit from krh:
Gtk+ also uses its wayland backend by default, so after this change,
it now dies instead of falings back to the x11 backend on non-wayland sessions.
I've filed https://bugzilla.gnome.org/show_bug.cgi?id=753635 to change
behavior to treat wayland errors as debug messages now.
Still, I think this change is wrong headed. We've been trying to
cleave ourselves from environment variables for years in the default
case. Having to set this seems like a step backward.
This means having to jump through additional hoops when using systemd
--user sessions, it means
having to jump through an additional hoop when running a program from
a VT, and it means having
to jump through an additional hoop when ssh'ing in to debug something.
if a user runs a program it should show up on the default display in a
clean environment. save the environment variables for fringe cases
like nested compositors.
The problem purportedly getting fixed gives this as a rationale:
> Now suppose you launch Weston while running the Gnome session. Suddenly, all of the Gtk+ apps
> launched from Gnome will show up inside Weston instead. That's unexpected. There's also no good
> way to prevent that from happening (other than perhaps setting WAYLAND_DISPLAY to an invalid value > when launching an app).
It's wrong to say there's no good way to prevent programs from
launching on weston. This corner case, can be covered by setting the
GDK_BACKEND environment variable. edge cases should use environment
variables not the default case.
Furthermore, the commit says it's trying to fix a scenario where the
user is logged into X, but the commit actually breaks X logins
(because of the above log handler issue)! That means it wasn't
I don't think the commit is good idea at all, can we revert it ?
XDG_RUNTIME_DIR is supposed to free us from other environment variables.
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