It's possible for the output to be disconnected in just the right moment
for wlr_output to be NULL in the repaint handler, causing a crash. This
check fixes that crash.
Calling wlr_output_manager_v1_set_configuration with an enabled output
and a NULL mode is incorrect if the output doesn't support modes.
When DPMS'ing an output, wlr_output_enable(output, false) is called.
This de-allocates the CRTC and sets wlr_output.current_mode to NULL.
Because we mark DPMS'ed outputs as enabled, we also need to provide a
correct output mode. Add a field to sway_output to hold the current
mode.
Closes: https://github.com/swaywm/wlroots/issues/1867
When applying config, value mode->refresh is mHz; convert it to Hz before
assigning it to the temporary output config. oc->refresh_rate will
be converted back to mHz in set_mode function.
Fix debug log printing GHz instead of Hz.
Sometimes when using direct scan-out, some flickering between the
fullscreen app and the regular desktop could be seen.
This happened because we called wlr_output_attach_render and then
wlr_output_attach_buffer for direct scan-out. wlr_output_attach_render
makes the OpenGL context current but also attaches the OpenGL buffer to
the primary plane apparently (all of this happens inside
eglMakeCurrent).
This patch moves the scan-out logic outside of output_render, before
wlr_output_attach_render. This lines it up with rootston's
implementation. This also makes more sense since no rendering is
involved when using direct scan-out.
Sorry about that, I should've tested this with more clients. The new
code has been tested with mpv and a GLFW demo.
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.
This commit si similar to wlroots' ca45f4490ccc ("Remove all wayland-server.h
includes").
handle_destroy would mark the output es being destroyed and commit the
transaction. Committing the transaction results in the output being
freed, the output manager can not retrieve the server reference
afterwards, resulting in the following use-after-free:
==22746==ERROR: AddressSanitizer: heap-use-after-free on address 0x614000017088 at pc 0x560c1ac17136 bp 0x7ffeab146f20 sp 0x7ffeab146f10
READ of size 8 at 0x614000017088 thread T0
#0 0x560c1ac17135 in handle_destroy ../sway/desktop/output.c:566
#1 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#2 0x7f38af5d3dfc in drm_connector_cleanup ../subprojects/wlroots/backend/drm/drm.c:1448
#3 0x7f38af5d2058 in scan_drm_connectors ../subprojects/wlroots/backend/drm/drm.c:1240
#4 0x7f38af5c6a59 in drm_invalidated ../subprojects/wlroots/backend/drm/backend.c:135
#5 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#6 0x7f38af5e827a in udev_event ../subprojects/wlroots/backend/session/session.c:52
#7 0x7f38aef5d7f1 in wl_event_loop_dispatch (/usr/lib/libwayland-server.so.0+0xa7f1)
#8 0x7f38aef5c39b in wl_display_run (/usr/lib/libwayland-server.so.0+0x939b)
#9 0x560c1ac0afbe in server_run ../sway/server.c:225
#10 0x560c1ac09382 in main ../sway/main.c:397
#11 0x7f38aed35ce2 in __libc_start_main (/usr/lib/libc.so.6+0x23ce2)
#12 0x560c1abea10d in _start (/usr/local/bin/sway+0x3910d)
0x614000017088 is located 72 bytes inside of 432-byte region [0x614000017040,0x6140000171f0)
freed by thread T0 here:
#0 0x7f38af82df89 in __interceptor_free /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cc:66
#1 0x560c1acbd1ed in output_destroy ../sway/tree/output.c:243
#2 0x560c1ac23ce5 in transaction_destroy ../sway/desktop/transaction.c:66
#3 0x560c1ac26b71 in transaction_progress_queue ../sway/desktop/transaction.c:348
#4 0x560c1ac284ca in transaction_commit_dirty ../sway/desktop/transaction.c:539
#5 0x560c1ac17110 in handle_destroy ../sway/desktop/output.c:564
#6 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#7 0x7f38af5d3dfc in drm_connector_cleanup ../subprojects/wlroots/backend/drm/drm.c:1448
#8 0x7f38af5d2058 in scan_drm_connectors ../subprojects/wlroots/backend/drm/drm.c:1240
#9 0x7f38af5c6a59 in drm_invalidated ../subprojects/wlroots/backend/drm/backend.c:135
#10 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#11 0x7f38af5e827a in udev_event ../subprojects/wlroots/backend/session/session.c:52
#12 0x7f38aef5d7f1 in wl_event_loop_dispatch (/usr/lib/libwayland-server.so.0+0xa7f1)
previously allocated by thread T0 here:
#0 0x7f38af82e5a1 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cc:95
#1 0x560c1acbc228 in output_create ../sway/tree/output.c:91
#2 0x560c1ac17ba2 in handle_new_output ../sway/desktop/output.c:656
#3 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#4 0x7f38af5e4ce8 in new_output_reemit ../subprojects/wlroots/backend/multi/backend.c:143
#5 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#6 0x7f38af5d26d4 in scan_drm_connectors ../subprojects/wlroots/backend/drm/drm.c:1294
#7 0x7f38af5c6a59 in drm_invalidated ../subprojects/wlroots/backend/drm/backend.c:135
#8 0x7f38af69330e in wlr_signal_emit_safe ../subprojects/wlroots/util/signal.c:29
#9 0x7f38af5e827a in udev_event ../subprojects/wlroots/backend/session/session.c:52
#10 0x7f38aef5d7f1 in wl_event_loop_dispatch (/usr/lib/libwayland-server.so.0+0xa7f1)
SUMMARY: AddressSanitizer: heap-use-after-free ../sway/desktop/output.c:566 in handle_destroy
Shadow bytes around the buggy address:
0x0c287fffadc0: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
0x0c287fffadd0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c287fffade0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c287fffadf0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c287fffae00: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
=>0x0c287fffae10: fd[fd]fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c287fffae20: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c287fffae30: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fa fa
0x0c287fffae40: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
0x0c287fffae50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c287fffae60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Retrieve the reference before the output is destroyed and update the
output_management state with the saved reference.
When setting fullscreen on a hidden scratchpad container, there was a
check to see if there was an existing fullscreen container on the
workspace so it could be fullscreen disabled first. Since the workspace
is NULL, it would cause a SIGSEGV. This adds a NULL check to avoid the
crash.
This also changes the behavior of how fullscreen is handled when adding
a container to the scratchpad or changing visibility of a scratchpad
container to match i3's. The behavior is as follows:
- When adding a container to the scratchpad or hiding a container back
into the scratchpad, there is an implicit fullscreen disable
- When setting fullscreen on a container that is hidden in the
scratchpad, it will be fullscreen when shown (and fullscreen disabled
when hidden as stated above)
- When setting fullscreen global on a container that is hidden in the
scratchpad, it will be shown immediately as fullscreen global. The
container is not moved to a workspace and remains in the
scratchpad. The container will be visible until fullscreen disabled
or killed. Since the container is in the scratchpad, running
`scratchpad show` or `move container to scratchpad` will have no
effect
This also changes `container_replace` to transfer fullscreen and
scratchpad status.
This makes it so there will only be one swaybg instance running
instead of one per output. swaybg's cli has been changed to a xrandr
like interface, where you select an output and then change properties
for that output and then select another output and repeat. This also
makes it so swaybg is only killed and respawned when a background
changes or when reloading.
This removes `output_find_config`, which would take the first matching
output config it found. This is fine if only a name output config,
identifier output config, or even just wildcard exist, but if there is
a name output config and identifier output config, they are not merged.
Instead, this introduces find_output_config, which is just a wrapper
for `get_output_config`. This ensures that both the name and identifier
output configs are respected.
This fixes the following case:
- For simplicity in this example, remove all output configs from config
- Run `swaymsg output <name> bg #ff0000 solid_color`
- Run `swaymsg output <identifier> scale 2`
- Disconnect and reconnect output
Without this, the output will have the background, but not the scale.
With this, the output will have both the background and scale
This removes `output_damage_view` since it is unnecessary. The logic
has been moved into its only caller `output_damage_from_view`. When
damaging the whole view, `output_damage_whole_container` should be used
instead
This adds an iterative call in `output_damage_whole_container` to
damage the subsurfaces for all visible views that are inside of the
container. This is needed to damage subsurfaces that extend outside the
box of the container. Without this, those subsurfaces will create
artifacts when moving or resizing.
This modifies the places where output_get_active_workspace is called to
handle a NULL result. Some places already handled it and did not need a
change, some just have guard off code blocks, others return errors, and
some have sway_asserts since the case should never happen. A lot of this
is probably just safety precautions since they probably will never be
called when `output_get_active_workspace` is not fully configured with a
workspace.
If an output's node was dirty and the transaction was committed before a
workspace was moved to or created for the output, the instruction would
have a bad value for `state->active_workspace` due to a missing
length check in `output_get_active_workspace`. If there was no focus on
the output, the first workspace was being returned. If the workspace
list was currently empty, the value was either garbage, or in the case of
an output being disabled and re-enabled, a workspace that may have been
previously freed. This just adds the length check to avoid returning out
of bounds value.
Just a convenience function that improves readability of the code.
Other things worth noting:
* container_get_siblings and container_sibling_index no longer use the
const keyword
* container_handle_fullscreen_reparent is only ever called after
attaching the container to a workspace, so its con->workspace check has
been changed to an assertion
This commit mostly duplicates the wlr_log functions, although
with a sway_* prefix. (This is very similar to PR #2009.)
However, the logging function no longer needs to be replaceable,
so sway_log_init's second argument is used to set the exit
callback for sway_abort.
wlr_log_init is still invoked in sway/main.c
This commit makes it easier to remove the wlroots dependency for
the helper programs swaymsg, swaybg, swaybar, and swaynag.
If output->configured is true, then the output has been modeset correctly and
we don't need to try again. If output->enabled is true, then we are in the
process of configuring the output and we shouldn't do anything.
This happens if you plug in more outputs than supported by your GPU.
This patch makes it so outputs without CRTCs appear as disabled. As soon as
they get a CRTC (signalled via the mode event), we can enable them.
This splits each seat operation (drag/move tiling/floating etc) into a
separate file and introduces a struct sway_seatop_impl to abstract the
operation.
The move_tiling_threshold operation has been merged into move_tiling.
The main logic for each operation is untouched aside from variable
renames.
The following previously-static functions have been made public:
* node_at_coords
* container_raise_floating
* render_rect
* premultiply_alpha
* scale_box
This combines `output_by_name` and `output_by_identifier` into a single
function called `output_by_name_or_id`. This allows for output
identifiers to be used in all commands, simplifies the logic of the
callers, and is more efficient since worst case is a single pass through
the output list.
This renames/moves the following properties:
* sway_view.{x,y,width,height} ->
sway_container.content_{x,y,width,height}
* This is required to support placeholder containers as they don't
have a view.
* sway_container_state.view_{x,y,width,height} ->
sway_container_state.content_{x,y,width,height}
* To remain consistent with the above.
* sway_container_state.con_{x,y,width,height} ->
sway_container_state.{x,y,width,height}
* The con prefix was there to give it contrast from the view
properties, and is no longer useful.
The function container_set_geometry_from_floating_view has also been
renamed to container_set_geometry_from_content.
The input manager is a singleton object. Passing the sway_input_manager
argument to each of its functions is unnecessary, while removing the
argument makes it obvious to the caller that it's a singleton. This
patch removes the argument and makes the input manager use server.input
instead.
On a similar note:
* sway_input_manager.server is removed in favour of using the server
global.
* seat.input is removed because it can get it from server.input.
Due to a circular dependency, creating seat0 is now done directly in
server_init rather than in input_manager_create. This is because
creating seats must be done after server.input is set.
Lastly, it now stores the default seat name using a constant and removes
a second reference to seat0 (in input_manager_get_default_seat).
The basic idea here is to apply rounding after scaling. It's not as
simple as this, though, and I've detailed it in the comments for a
function.
In order to fix some pixel leaks in the title bar, I found it easier to
change how we place rectangles to fill the area. Instead of placing two
rectangles across the full width above and below the title and having
shorter rectangles in the inner area, it's now pieced together in
vertical chunks. This method involves drawing two less rectangles per
container.
This introduces a new view_impl function: is_transient_for. Similar to
container_has_ancestor but works using the surface parents rather than
the tree.
This patch modifies view_is_visible, container_at and so on to allow
transient views to function normally when they're in front of a
fullscreen view.
This commit changes the meaning of sway_container so that it only refers
to layout containers and view containers. Workspaces, outputs and the
root are no longer known as containers. Instead, root, outputs,
workspaces and containers are all a type of node, and containers come in
two types: layout containers and view containers.
In addition to the above, this implements type safe variables. This
means we use specific types such as sway_output and sway_workspace
instead of generic containers or nodes. However, it's worth noting that
in a few places places (eg. seat focus and transactions) referring to
them in a generic way is unavoidable which is why we still use nodes in
some places.
If you want a TL;DR, look at node.h, as well as the struct definitions
for root, output, workspace and container. Note that sway_output now
contains a workspaces list, and workspaces now contain a tiling and
floating list, and containers now contain a pointer back to the
workspace.
There are now functions for seat_get_focused_workspace and
seat_get_focused_container. The latter will return NULL if a workspace
itself is focused. Most other seat functions like seat_get_focus and
seat_set_focus now accept and return nodes.
In the config->handler_context struct, current_container has been
replaced with three pointers: node, container and workspace. node is the
same as what current_container was, while workspace is the workspace
that the node resides on and container is the actual container, which
may be NULL if a workspace itself is focused.
The global root_container variable has been replaced with one simply
called root, which is a pointer to the sway_root instance.
The way outputs are created, enabled, disabled and destroyed has
changed. Previously we'd wrap the sway_output in a container when it is
enabled, but as we don't have containers any more it needs a different
approach. The output_create and output_destroy functions previously
created/destroyed the container, but now they create/destroy the
sway_output. There is a new function output_disable to disable an output
without destroying it.
Containers have a new view property. If this is populated then the
container is a view container, otherwise it's a layout container. Like
before, this property is immutable for the life of the container.
Containers have both a `sway_container *parent` and
`sway_workspace *workspace`. As we use specific types now, parent cannot
point to a workspace so it'll be NULL for containers which are direct
children of the workspace. The workspace property is set for all
containers, except those which are hidden in the scratchpad as they have
no workspace.
In some cases we need to refer to workspaces in a container-like way.
For example, workspaces have layout and children, but when using
specific types this makes it difficult. Likewise, it's difficult for a
container to get its parent's layout when the parent could be another
container or a workspace. To make it easier, some helper functions have
been created: container_parent_layout and container_get_siblings.
container_remove_child has been renamed to container_detach and
container_replace_child has been renamed to container_replace.
`container_handle_fullscreen_reparent(con, old_parent)` has had the
old_parent removed. We now unfullscreen the workspace when detaching the
container, so this function is simplified and only needs one argument
now.
container_notify_subtree_changed has been renamed to
container_update_representation. This is more descriptive of its
purpose. I also wanted to be able to call it with whatever container was
changed rather than the container's parent, which makes bubbling up to
the workspace easier.
There are now state structs per node thing. ie. sway_output_state,
sway_workspace_state and sway_container_state.
The focus, move and layout commands have been completely refactored to
work with the specific types. I considered making these a separate PR,
but I'd be backporting my changes only to replace them again, and it's
easier just to test everything at once.
This commit changes the arrange code in a way that will support type
safe arguments.
The arrange_output et al functions are now public, however I opted not
to use them directly yet. I've kept the generic arrange_windows there
for convenience until type safety is fully implemented. This means this
patch has much less risk of breaking things as it would otherwise.
To be type safe, arrange_children_of cannot exist in its previous form
because the thing passed to it could be either a workspace or a
container. So it's now renamed to arrange_children and accepts a list_t,
as well as the parent layout and parent's box.
There was some code which checked the grandparent's layout to see if it
was tabbed or stacked and adjusted the Y offset of the grandchild
accordingly. Accessing the grandparent layout isn't easy when using type
safe arguments, and it seemed odd to even need to do this. I determined
that this was needed because a child of a tabbed container would have a
swayc Y matching the top of the tab bar. I've changed this so a child of
a tabbed container will have a swayc Y matching the bottom of the tab
bar, which means we don't need to access the grandparent layout. Some
tweaks to the rendering and autoconfigure code have been made to
implement this, and the container_at code appears to work without
needing any changes.
arrange_children_of (now arrange_children) would check if the parent had
gaps and would copy them to the child, effectively making the
workspace's gaps recurse into all children. We can't do this any more
without passing has_gaps, gaps_inner and gaps_outer as arguments to
arrange_children, so I've changed the add_gaps function to retrieve it
from the workspace directly.
apply_tabbed_or_stacked_layout has been split into two functions, as it
had different logic depending on the layout.
Lastly, arrange.h had an unnecessary include of transaction.h. I've
removed it, which means I've had to add it to several other files.
When we have type safety we'll need to have functions for
workspace_add_tiling and so on. This means the existing container
functions will be just for containers, so they are being moved to
container.c. At this point layout.c doesn't contain much else, so I've
relocated everything and removed the file.
* container_swap and its static functions have been moved to the swap
command and made static.
* container_recursive_resize has been moved to the resize command and
made static.
* The following have been moved to container.c:
* container_handle_fullscreen_reparent
* container_insert_child
* container_add_sibling
* container_add_child
* container_remove_child
* container_replace_child
* container_split
* enum movement_direction and sway_dir_to_wlr have been moved to util.c.
Side note: Several commands included layout.h which then included
root.h. With layout.h gone, root.h has to be included by those commands.
This list includes disabled outputs.
When sway_container is demoted, we'll need to store the root's children
(ie. enabled outputs) in the sway_root. It makes sense to put these in a
list called `outputs`, so I'm renaming the existing list in advance.
This changes the destroy functions to the following:
* output_begin_destroy
* output_destroy
* workspace_begin_destroy
* workspace_destroy
* container_begin_destroy
* container_destroy
* view_begin_destroy
* view_destroy
The terminology was `destroy` and `free`, and it has been changed to
`begin_destroy` and `destroy` respectively.
When the last output is disconnected, its workspaces will now be stashed
in the root. Upon connection of a new output they will be restored.
There is a new function `workspace_consider_destroy` which decides
whether the given workspace should be destroyed or not (ie. empty and
not visible).
Calling container_begin_destroy will no longer automatically reap the
parents. In some places we want to reap the parents and in some we
don't, so this is left to the caller.
container_reap_empty_recursive and container_reap_empty have been
combined into one function and it will recurse up the tree.
Workspaces previously had a magical `workspace->floating` container,
which had a layout of L_FLOATING and whose children were actual floating
views. This allowed some conveniences, but was a hacky solution because
the container has to be exempt from focus, coordinate transactions with
the workspace, and omit emitting IPC events (which we didn't do).
This commit changes it to be a list directly in the sway_workspace. The
L_FLOATING layout is no longer used so this has been removed as well.
* Fixes incorrect check in the swap command (it checked if the
containers had the L_FLOATING layout, but this layout applied to the
magical container).
* Introduces workspace_add_floating
This introduces the following `for_each` functions:
* root_for_each_workspace
* root_for_each_container
* output_for_each_workspace
* output_for_each_container
* workspace_for_each_container
And introduces the following `find` functions:
* root_find_output
* root_find_workspace
* root_find_container
* output_find_workspace
* output_find_container
* workspace_find_container
* container_find_child
And removes the following functions:
* container_descendants
* container_for_each_descendant
* container_find
This change is preparing the way for demoting sway_container. Eventually
these functions will accept and return sway_outputs, sway_workspaces and
sway_containers (meaning a C_CONTAINER or C_VIEW).
This change also makes it easy to handle abnormalities like the
workspace floating list, root's scratchpad list and (once implemented)
root's saved workspaces list for when there's no connected outputs.
Fixes the render and container_at order for popups.
Fixes#2210
For rendering:
* render_view_surfaces has been renamed to render_view_toplevels
* render_view_toplevels now uses output_surface_for_each_surface (which
is now public), as that function uses wlr_surface_for_each_surface which
doesn't descend into popups
* Views now have a for_each_popup iterator, which is used by the
renderer to render the focused view's popups
* When rendering a popup, toplevels (xdg subsurfaces) of that popup are
also rendered
For sending frame done, the logic has been updated to match the
rendering logic:
* send_frame_done_container no longer descends into popups
* for_each_popup is used to send frame done to the focused view's popups
and their child toplevels
For container_at:
* floating_container_at is now static, which means it had to be moved
higher in the file.
* container_at now considers popups for the focused view before checking
containers.
* tiling_container_at has been introduced, so that it doesn't call
container_at recursively (it would check popups recursively if it did)
The rendering code doesn't use the exclusive input surface at all
anymore to decide to skip rendering of shell surfaces. This fixes
a weird situation in which a client requests exclusive input but
isn't an overlay layer surface.
The renderer also renders all overlay surfaces in this situation,
not just one. This simplifies the code and fixes rendering when
there are more than one overlay surfaces (e.g. for a virtual
keyboard to type the lockscreen password).
This PR changes the way we handle transactions to a more simple method.
The new method is to mark containers as dirty from low level code
(eg. arranging, or container_destroy, and eventually seat_set_focus),
then call transaction_commit_dirty which picks up those containers and
runs them through a transaction. The old methods of using transactions
(arrange_and_commit, or creating one manually) are now no longer
possible.
The highest-level code (execute_command and view implementation
handlers) will call transaction_commit_dirty, so most other code just
needs to set containers as dirty. This is done by arranging, but can
also be done by calling container_set_dirty.
The title and marks textures would have their height set from the
config's computed max font height, but the textures were not regenerated
when the config's max font height changed which made a gap appear.
Rather than making it regenerate the title textures every time the
config font height was changed, I've changed it to just make the
textures the height of the title itself and fill any gap when rendering.
Also, the title_width and marks_width variables have been renamed to
make it more obvious that they are in output-buffer-local coordinates.
Fixes#1936.
Both sway_output and sway_layer_shell listen to wlr's output destroy event,
but sway_layer_shell needs to access into sway_output's data strucure and needs
to be destroyed first.
Resolve this by making sway_layer_shell listen to a new event that happens at
start of sway_output's destroy handler
We were freeing the sway_output immediately upon disconnect which left
a dangling pointer in the output's container. It then tried to use the
pointer when the container is freed.
We don't need to store the sway_output in an output's container which is
destroying, so the fix is to set the pointer to NULL and remove the use
in container_free.
Also added an arrange when the output is disconnected for good measure.
* The arrange_foo functions are now replaced with arrange_and_commit, or
with manually created transactions and arrange_windows x2.
* The arrange functions are now only called from the highest level
functions rather than from both high level and low level functions.
* Due to the previous point, view_set_fullscreen_raw and
view_set_fullscreen are both merged into one function again.
* Floating and fullscreen are now working with transactions.
Setting it to "rerender" will always re-render everything
regardless of the damaged region. Setting it to "highlight" will
clear the screen and render only damaged regions.
* Attach sticky containers to new workspaces when switching
* Fire the close event *before* we start destroying the workspace to
prevent a crash
Because the sticky container now follows the visible workspace, this
simplifies the rendering and container_at logic.
