Commit Graph

213 Commits

Author SHA1 Message Date
Simon Ser 0aefa18690 backend/x11: send more precise output present events
Instead of sending dummy output present events, use the X11 Present
extension to send more precise events.
2020-12-18 10:37:08 +01:00
Simon Ser 94fda895ac backend/x11: use DRI3Open to get DRM FD
Instead of relying on EGL to retrieve the DRM FD, query it from the
DRI3 extension.

Use the EGL GBM platform, and drop the EGL config.
2020-12-18 10:12:55 +01:00
Simon Ser 0dcdb5e7a1 backend/x11: fix DRI3 formats not used
We queried DRI3 formats, but we weren't using them. Because of a typo,
only render formats were used.

Fixes: c59aacf944 ("backend/x11: query modifiers supported by X11 server")
Closes: https://github.com/swaywm/wlroots/issues/2552
2020-12-17 17:02:09 +01:00
Simon Ser 87bd718de5
backend: use fcntl(F_DUPFD_CLOEXEC) instead of dup
This makes sure the CLOEXEC flag is set on the dup'ed FD.
2020-12-15 20:52:53 +01:00
Simon Ser 525fa6ada0
backend/x11: fix xinput mask mixed up with present
Don't mix xinput and present flags.

Fixes: d79a00bf02 ("backend/x11: switch to wlr_swapchain")
2020-12-13 12:21:21 +01:00
Simon Ser c59aacf944 backend/x11: query modifiers supported by X11 server 2020-12-13 12:16:52 +01:00
Simon Ser d79a00bf02 backend/x11: switch to wlr_swapchain 2020-12-13 12:16:52 +01:00
Simon Ser 154fe8696f backend/x11: log unhandled client messages 2020-11-24 14:57:25 +01:00
Simon Ser f6c36f8881 backend/x11: log unhandled X11 events 2020-11-24 14:57:25 +01:00
Simon Ser 52805feae9 backend/x11: log errors
Register an X11 error handler, and optionally use xcb-errors to print a
detailed message.
2020-11-24 14:57:25 +01:00
Isaac Freund 7693f61d81 Replace wlr_key_state with wl_keyboard_key_state
There's no reason to have duplicate enums
2020-11-11 10:58:38 +01:00
Simon Ser bf93d2e67c output: rename impl->rollback to rollback_render
The output backend API is now mostly state-less thanks to the atomic
hooks (commit and test). There is one exception though: attach_render.
This function makes the rendering context current. However sometimes the
compositor might decide not to render after attach_render (e.g. when
there's nothing new to render to the back buffer). Thus
wlr_output_rollback has been introduced to revert the pending state.

Because the output backend API is mostly state-less, the only thing
wlr_output_impl.rollback needs to do is revert the current rendering
context. Rename the function to rollback_render to make this clear. Add
a check in the common wlr_output code to only call rollback_render when
attach_buffer has been previously called.

On the long term, we'll be able to remove attach_render and
rollback_render together.
2020-06-19 11:50:42 -06:00
Simon Ser af2f69e6c1 render/egl: unset current context after swapping buffers
After swapping buffers, it doesn't make sense to perform more rendering
operations. Unset the context to reflect this.

This commit makes it so the context is always only current between
wlr_egl_make_current and wlr_egl_swap_buffers.

This is an alternative to [1].

[1]: https://github.com/swaywm/wlroots/pull/2212
2020-05-20 17:39:34 +02:00
Simon Ser 1edc42157b render/egl: introduce wlr_egl_unset_current
This function can be called after wlr_egl_make_current to cleanup the
EGL context. This avoids having lingering EGL contexts that make things
work by chance.

Closes: https://github.com/swaywm/wlroots/issues/2197
2020-05-19 14:56:20 +02:00
Simon Ser 9acca4fc73 backend: set EGL_RENDERABLE_TYPE and EGL_SURFACE_TYPE
Ensure these are set to the correct value.
2020-04-09 00:15:25 +00:00
Simon Ser 507d9bc19e Add wlr_output_impl.rollback
Most of the pending output state is not forwarded to the backend prior
to an output commit. For instance, wlr_output_set_mode just stashes the
mode without calling any wlr_output_impl function.
wlr_output_impl.commit is responsible for applying the pending mode.

However, there are exceptions to this rule. The first one is
wlr_output_attach_render. It won't go away before renderer v6 is
complete, because it needs to set the current EGL surface.

The second one is wlr_output_attach_buffer.
wlr_output_impl.attach_buffer is removed in [1].

When wlr_output_rollback is called, all pending state is supposed to be
cleared. This works for all the state except the two exceptions
mentionned above. To fix this, introduce wlr_output_impl.rollback.

Right now, the backend resets the current EGL surface. This prevents GL
commands from affecting the output after wlr_output_rollback.

This patch is required for FBO-based outputs to work properly. The
compositor might be using FBOs for its own purposes [2], having leftover
FBO state can have bad consequences.

[1]: https://github.com/swaywm/wlroots/pull/2097
[2]: https://github.com/swaywm/wlroots/pull/2063#issuecomment-597614312
2020-04-08 17:33:00 +02:00
Simon Ser d3bd5f2a7b backend: reset EGL surface after buffer swap
This prevents GL commands to affect a previously current EGL surface
after a buffer swap.
2020-04-08 17:33:00 +02:00
Simon Ser e041158988 output: introduce wlr_output_test 2020-04-08 16:31:21 +02:00
Simon Ser 9be1af3afb backend/x11: add support for adaptive_sync_enabled
This sets the _VARIABLE_REFRESH window property [1].

[1]: 0616b7ac90/src/vulkan/wsi/wsi_common_x11.c (L1374)
2020-03-06 21:32:58 +01:00
Simon Ser 5d1ba0f446 output: re-introduce atomic mode, enabled, scale and transform
This reverts commit 01f903874b and re-applies
commit ee5f98ad49.

Updates: https://github.com/swaywm/wlroots/issues/1640 (Atomic output updates issue)
See also: https://github.com/swaywm/wlroots/pull/1762 (Atomic output updates original PR)
See also: https://github.com/swaywm/wlroots/issues/1780 (Issue caused by atomic output updates)
See also: https://github.com/swaywm/sway/issues/4419 (Issue caused by atomic output updates)
See also: https://github.com/swaywm/wlroots/pull/1781 (Revert PR)
2019-12-30 11:21:11 -07:00
Simon Ser 4da4a15d6b output: add description
wlr_output.description is a string containing a human-readable string
identifying the output. Compositors can customise it via
wlr_output_set_description, for instance to make the name more
user-friendly.

References: https://github.com/swaywm/wlroots/issues/1623
2019-12-29 12:35:22 -05:00
Scott Anderson cff1c2f740 meson: Various improvements
Bumps minimum version to 0.51.0

- Remove all intermediate static libraries.
  They serve no purpose and are just add a bunch of boilerplate for
  managing dependencies and options. It's now managed as a list of
  files which are compiled into libwlroots directly.

- Use install_subdir instead of installing headers individually.
  I've changed my mind since I did that. Listing them out is annoying as
  hell, and it's easy to forget to do it.

- Add not_found_message for all of our optional dependencies that have a
  meson option. It gives some hints about what option to pass and what
  the optional dependency is for.

- Move all backend subdirectories into their own meson.build. This
keeps some of the backend-specific build logic (especially rdp and
session) more neatly separated off.

- Don't overlink example clients with code they're not using.
  This was done by merging the protocol dictionaries and setting some
  variables containing the code and client header file.
  Example clients now explicitly mention what extension protocols they
  want to link to.

- Split compositor example logic from client example logic.

- Minor formatting changes
2019-12-23 07:48:29 -05:00
Scott Anderson 685a5a11a9 backend/x11: Revert usage of present extension
This reverts commit 3317134adf.
This reverts commit a3c3b928a3.

There are some serious issues when running this on a real X server, as
opposed to running this on Xwayland, where this was tested.

More investigation needs to be done into why these issues happen and if
our usage of the present extension is correct.
2019-11-19 11:06:38 +01:00
Scott Anderson 3317134adf backend/x11: Drop required present version
We say 1.2, but I don't think we actually use anything that was
introduced past 1.0.
2019-11-18 11:53:17 +01:00
Scott Anderson a3c3b928a3 backend/x11: Give X11 a real rendering loop
Makes use of the present extension to get notified of vsync, and not
require any stupid timer hacks. Also make use of the present version of
ConfigureNotify, because why not?
2019-11-02 12:43:33 +01:00
Rouven Czerwinski 01f903874b Revert "output: atomic mode"
This reverts commit ee5f98ad49.

This intoduced problems where outputs could not be turned off because
they had flips pending.
2019-08-07 16:22:11 +09:00
Simon Ser ee5f98ad49 output: atomic mode, enabled, scale and transform
This commit makes more output properties (mode, enabled, scale and transform)
atomic. This means that they are double-buffered and only applied on commit.

Compositors now need to call wlr_output_commit after setting any of those
properties.

Internally, backends still apply properties sequentially. The behaviour should
be exactly the same as before. Future commits will update some backends to take
advantage of the atomic interface. Some backends are non-atomic by design, e.g.
the X11 backend or the legacy DRM backend.

Updates: https://github.com/swaywm/wlroots/issues/1640
2019-08-02 10:01:29 -04:00
Simon Ser ca45f4490c Remove all wayland-server.h includes
The documentation for wayland-server.h says:

> Use of this header file is discouraged. Prefer including
> wayland-server-core.h instead, which does not include the server protocol
> header and as such only defines the library PI, excluding the deprecated API
> below.

Replacing wayland-server.h with wayland-server-core.h allows us to drop the
WL_HIDE_DEPRECATED declaration.
2019-07-27 15:49:32 -04:00
Sebastian Krzyszkowiak 415267ac13 backends/x11: Touch support
Closes #1749
2019-07-17 09:23:10 -04:00
Dorota Czaplejewicz 5027b23dc2 x11: Send a frame event on the pointer after button events
Without the immediate frame event, the button event would not be processed in time: https://source.puri.sm/Librem5/phoc/issues/
2019-06-17 16:01:29 +03:00
Simon Ser ce3f4c3fe1 output: remove wlr_output_impl.transform
The backend doesn't need to handle transform changes, since everything is done
in software. In fact, all of the implementations were all identical and just
set the transform.

We could add support for hardware transforms, but:

- This would require a different field (something like hardware_transform)
- Not all combinations are possible because there often are hardware
  limitations
- The Wayland protocol isn't ready for this (in particular xdg-output, see [1])

This belongs to a different patch series anyway.

[1]: https://patchwork.freedesktop.org/series/52324/
2019-06-16 10:51:49 -04:00
Simon Ser 20690346c7 output: rename needs_commit to needs_frame
This new name makes more sense, since it is a request from the backend to get
a new frame. In the future a commit may not convey a new frame.
2019-04-23 14:34:30 -06:00
Simon Ser 9a0f8a194c output: refactor backend API
This updates the backend part of the output API. This is mostly renaming:
make_current becomes attach_render and swap_buffers becomes commit.

This also fixes the RDP backend to support NULL damage.
2019-04-23 14:34:30 -06:00
Jan Beich b6d0de177a backend: unbreak on 32-bit architectures
backend/headless/output.c:132:3: error: format specifies type 'long' but the argument has type 'size_t' (aka 'unsigned int') [-Werror,-Wformat]
                ++backend->last_output_num);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~
backend/noop/output.c:72:3: error: format specifies type 'long' but the argument has type 'size_t' (aka 'unsigned int') [-Werror,-Wformat]
                ++backend->last_output_num);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~
backend/wayland/output.c:294:3: error: format specifies type 'unsigned long' but the argument has type 'size_t' (aka 'unsigned int') [-Werror,-Wformat]
                ++backend->last_output_num);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~
backend/x11/output.c:150:3: error: format specifies type 'long' but the argument has type 'size_t' (aka 'unsigned int') [-Werror,-Wformat]
                ++x11->last_output_num);
                ^~~~~~~~~~~~~~~~~~~~~~
2019-04-08 14:03:15 -06:00
Brian Ashworth b135599e5a backend/x11: improve output number handling
This improves the way the output numbers are handled for the x11
backend. Instead of using the number of active outputs plus one, the
last used number is stored and new outputs will increment it. This
fixes the situation where you start with one output, create a second,
close the first, and create a third. Without this, both outputs will be
X11-2, which causes an issue since the identifier will also be
identical. With this, the last output is X11-3 and the outputs can be
distinguished.
2019-03-15 18:37:35 +02:00
emersion 5de26ad8ed
pointer: add a frame event
Frame events group logically connected pointer events. It makes sense to make
the backend responsible for sending frame events, since once the events are
split (ie. once the frame events are stripped) it's not easy to figure out
which events belongs to which frame again.

This is also how Weston handles frame events.

Fixes https://github.com/swaywm/wlroots/issues/1468
2019-01-26 11:04:05 +01:00
Jente Hidskes 85d84a1a04
backend/x11 & backend/wayland: make set_title NULL-safe
Set the default "wlroots - " title when the title argument to the
set_title functions is NULL. Otherwise, for at least the Wayland
backend, we'd crash because xdg_toplevel_set_title doesn't handle a NULL
pointer.
2019-01-24 15:18:28 +01:00
Jente Hidskes edf0e49195
Add wlr_x11_output_set_title 2019-01-20 16:21:04 +01:00
Jan Beich f80d174e8b Simplify evdev includes on FreeBSD by relying on up-to-date package
As evdev-proto is installed by CI some files have been missed:

 ../examples/pointer-constraints.c:2:10: fatal error: 'linux/input-event-codes.h' file not found
 #include <linux/input-event-codes.h>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~
 ../examples/relative-pointer-unstable-v1.c:5:10: fatal error: 'linux/input-event-codes.h' file not found
 #include <linux/input-event-codes.h>
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~
2019-01-07 08:08:47 +00:00
Scott Anderson d3ee69f76b backend/x11: Hide cursor with Xfixes 2018-11-13 10:55:03 +13:00
Scott Anderson 70ae76304e backend/x11: Remove old input functions
This also allows us to remove xcb-xkb, since Xinput will now give us the
appropriate XKB modifiers with each event.
2018-11-13 10:55:03 +13:00
Scott Anderson d89e868cc9 backend/x11: Add new Xinput events 2018-11-13 10:42:02 +13:00
Scott Anderson 88b2d6fe25 backend/x11: Check for xinput extension 2018-11-13 10:41:37 +13:00
Scott Anderson 9c1b87f210 backend/x11: Move atom initilisation earlier
There isn't any real reason to delay this until the backend is started.
2018-11-13 10:40:52 +13:00
Scott Anderson ab2c57984b backend/x11: Make header order consistent 2018-11-13 10:40:52 +13:00
Scott Anderson 51a283cbe4 backend/x11: Rename xcb_conn to xcb
When the Xlib connection is removed, this _conn suffix is going to be
pointless. I'm removing this preemtively for that.
2018-11-13 10:39:24 +13:00
emersion 51bfdd620e
Use #if instead of #ifdef for wlroots config data
This prevents some annoying issues when e.g. not including wlr/config.h or
making a typo in the guard name.
2018-11-12 10:12:46 +01:00
emersion 09550032b7
render: correctly set EGL_RENDERABLE_TYPE
This should be set to EGL_OPENGL_ES2_BIT.

Also fixes EGL config attributes in the headless and X11 backends.
2018-11-10 13:20:54 +01:00
emersion eac7c2ad2f output: add presentation refresh prediction 2018-10-04 22:00:24 +02:00
emersion 26b9d6dbb1 output: send present event from all backends 2018-10-04 21:56:38 +02:00
emersion 02231554c8 backend/x11: add assertions 2018-09-18 11:06:01 +02:00
random human 7bc2657984
Free unused pointer in x11/backend.c 2018-09-02 20:52:09 +05:30
Scott Anderson fd3fa760d3 Revert "Revert "Merge pull request #1194 from ascent12/meson_feature""
This reverts commit 9c886f20b9.
2018-08-24 19:35:02 +12:00
Drew DeVault 9c886f20b9 Revert "Merge pull request #1194 from ascent12/meson_feature"
This breaks wlroots when used as a meson subproject.

This reverts commit dea311992e, reversing
changes made to 6db9c4b746.
2018-08-23 21:00:58 -04:00
Scott Anderson 784c20c82f Use new options for X11 backend and Xwayland 2018-08-22 20:27:37 +12:00
sdilts 8e7df5eb88 Fix xcb_create_window parameters
Set the window width and height, not the location of the window.
2018-08-10 18:05:34 -06:00
sdilts da79fef5f7 Add guard for changing the size of X11 backend windows
Events that set the window to either a width or height of zero are now
ignored and logged.
2018-08-09 22:09:48 -06:00
sdilts 55cca6deaa Set default output size for X11 backend
Fixes issue #1170
Also set the created window size to match the output size.
2018-08-09 22:05:18 -06:00
Drew DeVault 4b096fc114 Revert "Merge pull request #1153 from emersion/include-config"
This reverts commit ef0a6ea4d2, reversing
changes made to 8d03bc9178.
2018-07-21 09:44:20 -04:00
emersion 41094a7df5 Always include config.h 2018-07-21 13:08:23 +01:00
Guido Günther 40fe252c2d x11: make sure event source is drained
Otherwise running under Xvfb will not deliver any events. This results
in e.g. weston-info reporting a 0x0 window size (which results in all
sorts of problems).
2018-07-11 17:34:43 +02:00
Guido Günther 8515b7c65b x11: use correct type for events in wl_event_loop_add_fd 2018-07-11 17:30:45 +02:00
Guido Günther e463b49166 x11: Check if xcb_configure_window worked
So far we did not check for any errors
2018-07-11 17:29:41 +02:00
emersion 7cbef15206
util: add wlr_ prefix to log symbols 2018-07-09 22:49:54 +01:00
Dominique Martinet bcc2c64c1e x11 backend init: fix leak on failed XOpenDisplay
Found through static analysis
2018-06-30 11:38:21 +09:00
Ilia Bozhinov 24cf70ae96 backends: implement custom EGL and renderer initialization
Compositors now have more control over how the backend creates its
renderer. Currently all backends create an EGL/GLES2 renderer, so
the necessary attributes for creating the context are passed to a
user-provided callback function. It is responsible for initializing
provided wlr_egl and to return a renderer. On fail, return 0.

Fixes #987
2018-05-25 14:56:52 +03:00
emersion 0b58579564
Add support for discrete axis values 2018-05-12 13:34:58 +01:00
Guido Günther 6f01c12b40 backend/x11: don't transform pointer events
We do this in a backend independent way in wlr_cursor now.
2018-05-03 11:09:14 +02:00
emersion 178ac8bffe
backend/{wayland,x11}: fix pointer coords for transformed outputs 2018-04-30 10:48:35 +01:00
emersion 62d7337d00
backend/x11: add one pointer per output 2018-04-29 14:46:29 +01:00
emersion f8e0a03451
backend/x11: correctly destroy input devices 2018-04-28 12:55:36 +01:00
emersion 79da4c175e
backend/headless: remove useless destructor 2018-04-28 12:48:05 +01:00
Drew DeVault fecb971518
Merge pull request #902 from emersion/various-memory-leaks
Various memory leaks
2018-04-26 11:34:49 +02:00
emersion cd9f25711c
backend: destroy renderer when destroying backend 2018-04-25 23:53:43 +01:00
emersion 625a7a48dc
Don't use the wlr_ prefix for static functions 2018-04-25 23:51:00 +01:00
emersion 71ca45e2c0
Make sure we don't use others' prefixes 2018-04-25 23:24:58 +01:00
emersion eaed6bd03b
render/egl: add wlr_egl_destroy_surface 2018-04-24 23:44:43 +01:00
Uli Schlachter e5ab12339f x11 backend: Expose events mean "needs swap"
When the X11 server sends an expose event, that means that "this
rectangle here (the event contains x,y,width,height) has undefined
contents on your window; please redraw that". This means that we need a
swap. However, so far the code does not actually enforce that a swap
happens.

For example, start rootston, switch to another workspace and then switch
back. The rootston window will not be redrawn (before commit
52b058c2a3, it would just be fully white; after that commit it will
show whatever was visible on the old workspace). This is because the
drawing code concludes that nothing needs to be done. However, in fact a
swap is necessary.

This reverts commit e79d924588, because its optimisation is already
done now: wlr_output_update_needs_swap() emits a signal, which is
handled by wlr_output_damage with a call to wlr_output_schedule_frame().
This function does nothing if a frame is already pending. Thus, the
optimisation from commit e79d924588 now happens implicitly.

Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-04-15 11:41:09 +02:00
Uli Schlachter e79d924588 x11 backend: Ignore expose if frame is pending
When resizing rootston with the mouse, the result is really slow. One
can see that rootston needs quite a while for drawing the newly visible
area. This is because every single expose event is handled on its own
and causes (apparently) a full repaint or at least a swap.

This commit improves things by only causing a new frame if none is
pending already.

With this change, there is almost no delay in rootston drawing the newly
visible area.

Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-04-15 11:07:31 +02:00
Uli Schlachter 52b058c2a3 x11 backend: Do not set a back pixel on windows
Before this commit, the x11 server would fill any exposed area with
white before the wlroots x11 backend got a chance to do anything. This
was e.g. visible when running rootston and resizing the window: When the
window becomes larger, the new area is filled with black.

By just not setting a back pixel value, this commit gets rid of this
behaviour.

Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-04-15 11:07:31 +02:00
Uli Schlachter 98f8ec6a08 x11_handle_input_event: Remove return value
handle_x11_event() and x11_handle_input_event() react to different kinds
of events, so it does not make much of a difference if
x11_handle_input_event() signals if it handled an event or not.

Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-04-15 10:33:53 +02:00
Uli Schlachter 3728abd1fc handle_x11_event: Remove return value
This function always returns "false", so its return type can simply be
changed to void.

Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-04-15 10:32:30 +02:00
emersion d2ebbd103c
backend: remove wlr_backend_get_egl 2018-04-08 11:00:56 -04:00
emersion 03563b61a8
backend/{x11,headless}: use default if supplied refresh is invalid 2018-04-05 22:48:00 -04:00
emersion 2d6bbf12f8
backend/{x11,headless}: fix refresh rate 2018-04-03 22:54:01 -04:00
emersion 9609985f29
backend/x11: fix cursor position when receiving configure event 2018-04-03 13:32:24 -04:00
emersion 60f07ee321
backend/x11: fix WLR_HAS_XCB_XKB always undefined 2018-04-03 13:12:52 -04:00
Drew DeVault 8b37e8f67a
Merge pull request #792 from emersion/x11-backend-blank-cursor
backend/x11: hide cursor
2018-04-02 10:21:07 -04:00
emersion 33a2eb4b77
Untie wlr_backend from wlr_renderer 2018-03-31 18:49:43 -04:00
emersion 37aae0b2cd
backend/x11: flush after destroying window
Otherwise the destroy message is kept buffered and never reaches
the X11 server. Thanks X11.
2018-03-31 13:28:50 -04:00
emersion 7b88ace557
backend/x11: hide cursor 2018-03-31 12:10:43 -04:00
emersion 5111f7df84
backend/x11: fix extra output 2018-03-30 23:51:20 -04:00
emersion aa6ae710f7
backend/x11: fix input events 2018-03-30 23:51:19 -04:00
emersion 0a7a8cbd1c
backend/x11: add WLR_X11_OUTPUTS support 2018-03-30 23:51:19 -04:00
emersion d4f7ced6e2
backend/x11: refactor, prepare support for multiple outputs 2018-03-30 23:51:16 -04:00
emersion 5dd022da13
Merge pull request #765 from swaywm/transformed-events
Use libinput transformed events instead of width_mm/height_mm
2018-03-28 14:11:39 -04:00
Drew DeVault a35a5786b0 Remove width_mm from wlr_pointer events 2018-03-28 10:46:50 -04:00
emersion f033f717a2
backend/x11: make xcb-xkb optional, remove global state 2018-03-28 00:26:15 -04:00
emersion 8d1b5c7600
backend/x11: correctly update keyboard modifiers 2018-03-28 00:04:32 -04:00
Uli Schlachter c7f8b28d8d Fix use-after-free in x11 backend during shutdown
The xcb_connection_t instance that is used here comes from
XGetXCBConnection(), is created by XOpenDisplay(), and is owned by the
returned Display*. Calling xcb_disconnect() directly on it leads to
various use-after-frees during shutdown, as reported by valgrind. The
first one of the about 30 errors is:

    Invalid read of size 4
       at 0x71F2051: xcb_take_socket (in /usr/lib64/libxcb.so.1.1.0)
       by 0x78551DD: ??? (in /usr/lib64/libX11.so.6.3.0)
       by 0x7855A14: _XFlush (in /usr/lib64/libX11.so.6.3.0)
       by 0x7858504: _XGetRequest (in /usr/lib64/libX11.so.6.3.0)
       by 0x7838966: XFreeGC (in /usr/lib64/libX11.so.6.3.0)
       by 0x783238B: XCloseDisplay (in /usr/lib64/libX11.so.6.3.0)
       by 0x4E680C2: wlr_x11_backend_destroy (backend.c:333)
       by 0x4E57E94: wlr_backend_destroy (backend.c:39)
       by 0x4E629FB: multi_backend_destroy (backend.c:47)
       by 0x4E62B5A: handle_display_destroy (backend.c:90)
       by 0x50B7E9F: ??? (in /usr/lib64/libwayland-server.so.0.1.0)
       by 0x50B8476: wl_display_destroy (in /usr/lib64/libwayland-server.so.0.1.0)
     Address 0xc14dda0 is 0 bytes inside a block of size 21,152 free'd
       at 0x4C2DD18: free (vg_replace_malloc.c:530)
       by 0x4E680A5: wlr_x11_backend_destroy (backend.c:330)
       by 0x4E57E94: wlr_backend_destroy (backend.c:39)
       by 0x4E629FB: multi_backend_destroy (backend.c:47)
       by 0x4E62B5A: handle_display_destroy (backend.c:90)
       by 0x50B7E9F: ??? (in /usr/lib64/libwayland-server.so.0.1.0)
       by 0x50B8476: wl_display_destroy (in /usr/lib64/libwayland-server.so.0.1.0)
       by 0x40C54E: main (main.c:84)
     Block was alloc'd at
       at 0x4C2EA1E: calloc (vg_replace_malloc.c:711)
       by 0x71F0C60: xcb_connect_to_fd (in /usr/lib64/libxcb.so.1.1.0)
       by 0x71F4BD4: xcb_connect_to_display_with_auth_info (in /usr/lib64/libxcb.so.1.1.0)
       by 0x7854AA1: _XConnectXCB (in /usr/lib64/libX11.so.6.3.0)
       by 0x7845481: XOpenDisplay (in /usr/lib64/libX11.so.6.3.0)
       by 0x4E681B6: wlr_x11_backend_create (backend.c:376)
       by 0x4E580EE: wlr_backend_autocreate (backend.c:99)
       by 0x40C27D: main (main.c:35)

Normally, one would expect this to crash during XCloseDisplay() when
xcb_disconnect() is called again and frees the same data again (glibc would
detect a double free). However, XCloseDisplay() tries to clean up some internal
caches first for which it has to send requests to the X11 server (e.g. the
XFreeGC() above). This fails since the file descriptor was already closed,
which causes an IO error. Xlib's _XDefaultIOError() handles this by printing an
error message and calling exit(1).

Thus, the only symptom of this problem was compositors exiting
mid-shutdown and printing an error message:

    XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0"
          after 6 requests (6 known processed) with 0 events remaining.

Fixes: https://github.com/swaywm/wlroots/issues/745
Signed-off-by: Uli Schlachter <psychon@znc.in>
2018-03-26 10:48:30 +02:00