This commit refactors `cursor_handle_activity` to also take the idle
source, so that it can be reused for tablet and touch activity.
Previously, the timeouts would be tracked, but the cursor would never be
un-hidden for anything but pointers.
Fixes#5169.
If we started holding the tool tip down on a surface that accepts tablet
v2, we should notify that surface if it gets released over a surface
that doesn't support v2.
Since GTK supports tablet v2, this fixes the common case of starting a
drag over a GTK surface (e.g. scrollbar) and releasing it outside (e.g.
over the gaps between sway containers, or in a terminal).
Refs #5230.
Instead of handling presses and releases on empty workspaces as setting
focus to the workspace, handle releases by notifying the seat of a
pointer action. This way DnDs are correctly released if the button is
released over an empty workspace. This is achieved by removing the early
return and letting the handle_button() call seat_pointer_notify_button()
at the very end.
Fixes#3932
This allows e.g. triggering one command while a key is held, then
triggering another to undo the change performed by it afterwards. One
use case for this is triggering push-to-talk functionality for VoIP
tools without granting them full access to all input events.
Fixes#3151
If a pad device for a tablet exists, reloading the configuration,
removing/reading the device or even suspending the system will recreate
the same Wayland input device multiple times.
Make sure we don't re-create the same Wayland device more than
necessary.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Add a command to influence keyboard shortcuts inhibitors. In its current
form it can be used to activate, deactivate or toggle an existing
inhibitor on the surface currently receiving input. This can be used to
define an escape shortcut such as:
bindsym --inhibited $mod+Escape seat - shortcuts_inhibitor deactivate
It also allows the user to configure a per-seat default of whether
keyboard inhibitors are honoured by default (the default) or not. Using
the activate/toggle command they can then enable the lingering inhibitor
at a later time of their choosing.
As a side effect this allows to specifically address a named seat for
actions as well, whatever use-case that might serve.
Signed-off-by: Michael Weiser <michael.weiser@gmx.de>
Adding support for the keyboard shortcuts inhibit protocol allows remote
desktop and virtualisation software to receive all keyboard input in
order to pass it through to their clients so users can fully interact
the their remote/virtual session. The software usually provides its own
key combination to release its "grab" to all keyboard input. The
inhibitor can be deactivated by the user by removing focus from the
surface using another input device such as the pointer.
Use support for the procotol in wlroots to add support to sway. Extend
the input manager with handlers for inhibitor creation and destruction
and appropriate bookkeeping. Attach the inhibitors to the seats they
apply to to avoid having to search the list of all currently existing
inhibitors on every keystroke and passing the inhibitor manager around.
Add a helper function to retrieve the inhibitor applying to the
currently focused surface of a seat, if one exists.
Extend bindsym with a flag for bindings that should be processed even if
an inhibitor is active. Conversely this disables all normal shortcuts if
an inhibitor is found for the currently focused surface in
keyboard::handle_key_event() since they don't have that flag set. Use
above helper function to determine if an inhibitor exists for the
surface that would eventually receive input.
Signed-off-by: Michael Weiser <michael.weiser@gmx.de>
This fixes a crash when attempting to listen to a signal on a NULL
cursor image surface. If the surface is NULL, the listener is just
reinitialized using wl_list_init.
This adds a listener for the destroy event of the cursor image surface.
This prevents a use-after-free when the last visible image surface is
freed, there has not been a new cursor set, and the cursor is reshown.
This removes `seat <seat> keyboard_grouping keymap` and replaces it with
`seat <seat> keyboard_grouping smart`. The smart keyboard grouping will
group based on both the keymap and repeat info. The reasoning for this
is that deciding what the repeat info should be for a group is either
arbitrary or non-deterministic when multiple keyboards in the group have
repeat info configured (unless somehow exposed to the user in a
reproducible uniquely identifiable fashion).
When clicking on the titlebar of a floating container (or descendant of
a floating container), the top-level floating container was being
focused and then allowing you to move the top-level floating container.
This made it so you couldn't switch to a different tab/stack within the
floating container. With this patch, the focus inactive view for the
container that the titlebar is associated with is focused, then the
traversal to the top-level floating container is performed to use with
the move floating operation.
This defers the destruction of wlr_keyboard_groups until idle. This is
to prevent the keyboard group's keyboard from being destroyed in the
middle of handling a keyboard event. This would occur when changing the
keymap of the last keyboard in a group with a keyboard binding. The
prevents crashing when attempting to update the xkb state of the
keyboard group's keyboard. The sway_keyboard_group is still immediately
destroyed so that the group is no longer used
This adds two missing calls to wl_list_remove to remove the key and
modifier listeners for the keyboard group's keyboard when destroying
the keyboard group. This fixes some crashes when changing the keymap of
the last keyboard in a group with a keyboard binding.
This adds seat configuration options which can be used to configure what
events affect the idle behavior of sway.
An example use-case is mobile devices: you would remove touch from the
list of idle_wake events. This allows the phone to stay on while you're
actively using it, but doesn't wake from idle on touch events while it's
sleeping in your pocket.
Some wayland clients (mostly GTK3 apps) like eog or evince support
gestures like pinch-to-zoom. These gestures are given to clients
via the pointer_gestures_v1 protocol. This is already supported in
wlroots, so we just need to hook up the events here in sway.
Fixes#4724
If a sway keyboard is being destroyed, then the keyboard is being
removed from a seat. If the associated wlr_keyboard is the currently
set keyboard for the wlr_seat, then we need to reset the wlr_seat's
keyboard to NULL so it doesn't reference an invalid device for the seat.
The next configured keyboard from the seat or the next keyboard from
that seat that has an event will then become the seat keyboard.
Similarly, this needs to be done for a wlr_keyboard_group's keyboard
when the wlr_keyboard_group is being destroyed.
For the validation pass of reloading, there is no need to touch swaybg,
swaynag, inputs, outputs, or seats. This drastically improves the speed
of a reload by skipping over the expensive I/O configuration and
handling of wayland clients. As long as the syntax is valid, the
CMD_FAILURE's can be relayed during the actual reload.
In sway_keyboard_destroy, only remove the keyboard from a keyboard
group, if it is part of a keyboard group. If the keyboard is not part of
a keyboard group, then there is nothing to remove it from
When being created, non first seats would get through the list of devices
without the list being first initialised -> segfault.
Issue introduced with ab0248a545Fixes#4750: Crash when reloading Sway with multiple seats configured
A wlr_keyboard_group allows for multiple keyboard devices to be
combined into one logical keyboard. This is useful for keyboards that
are split into multiple input devices despite appearing as one physical
keyboard in the user's mind.
This adds support for wlr_keyboard_groups to sway. There are two
keyboard groupings currently supported, which can be set on a per-seat
basis. The first keyboard grouping is none, which disables all grouping
and provides no functional change. The second is keymap, which groups
the keyboard devices in the seat by their keymap. With this grouping,
the effective layout and repeat info is also synced across keyboard
devices in the seat. Device specific bindings will still be executed as
normal, but everything else related to key and modifier events will be
handled by the keyboard group's keyboard.
Sway has basic support for drawing tablets, but does not expose
properties such as pressure sensitivity. This implements the wlr tablet
v2 protocol, providing tablet events to Wayland clients.
Subsurfaces (in most cases popups) aren't decorated by sway
and will never have any borders, but may be drawn beyond container
boundaries producing false positive when searching for edge.
So we want to skip edge search when handling mouse event on subsurface.
This matches i3's behavior of only focusing a container when pressed.
This allows for `bindsym button1 nop`, `bindsym BTN_LEFT nop`, or
`bindcode 272 nop` to be used to disable focusing when clicking on the
title (or with additional flags to bind{code,sym} other portions of
the container).
Without this additional condition, the user would need both
`bindsym button1 nop` and `bindsym --release button1 nop` to override
both the pressed and released behavior.
Focused layers are not cleared when destroyed, they are cleared on unmap.
Giving focus to an unmapped layer surface is (1) incorrect and (2) triggers a
use-after-free.
Closes: https://github.com/swaywm/sway/issues/4517
This make seat_update_capabilities set cursor image only if
there was no pointer cap before update. This avoid resetting
cursor to left_ptr if an input device is removed.
This keeps track of whether surfaces received a key press event and
will only send a key release event if the pressed event was sent. This
also requires changing the keycodes that are sent via wl_keyboard_enter
to only include those that were previously sent. This makes it so
surfaces do not receive key release events for keys that they never
received a key press for and makes it so switching focus doesn't leak
keycodes that were consumed by bindings.
This adds an axis handler to seatop_down so that it is possible to
manually scroll while having a mouse button down. This is mainly useful
for selecting text. Some applications may not automatically scroll when
the cursor is near the edge of the application or the user may just
prefer manually scrolling for more control over the scrolling speed.
In handle_seat_node_destroy, it was possible to focus the node attached
to the seat node that is being destroyed when an empty workspace was
being destroyed in a multiple seat environment. This resulted in
infinite recursion when attempting to destroy the workspace. This just
moves the seat node destruction higher so it cannot be the focus
inactive for the seat. This is the same ordering that is applied to
destruction of seat nodes for containers
This just adds a small quality of life improvement to the cursor hiding
functionality. The cursor will no longer be hidden unless all buttons
are released.
This adds support for specifying a binding for a specific group. Any
binding without a group listed will be available in all groups. The
priority for matching bindings is as follows: input device, group, and
locked state.
For full compatibility with i3, this also adds Mode_switch as an alias
for Group2. Since i3 only supports this for backwards compatibility
with older versions of i3, it is implemented here, but not documented.
In sway_keyboard_config, do not change the keymap when the new keymap
is unchanged, unless this is during a config reload. The reasoning for
this is to prevent the effective layout from being reset to index 0 for
input config changes unrelated to the keymap.
This just fixes the check in set_send_events for whether the mode has
changed. LIBINPUT_CONFIG_SEND_EVENTS_ENABLED is 0 so the bitmask check
cannot be fixed, but Sway doesn't allow multiple modes to be set anyway
(not really sure why you would need to) so a basic equality check works
This adds a libinput_config change type to the input event for when
the libinput config for a device changes
In order for this to be possible to track, the libinput config code
had to be refactored. It is now extracted into a separate file to
isolate it from the rest of the input management code.
This adds an ipc event related to input devices. Currently the
following changes are supported:
- added: when an input device becomes available
- removed: when an input device is no longer available
- xkb_keymap_changed: (keyboards only) the keymap changed
- xkb_layout_changed: (keyboards only) the effective layout changed
Adds a new commend "xkb_file", which constructs the internal
xkb_keymap from a xkb file rather than an RMLVO configuration.
This allows greater flexibility when specifying xkb configurations.
An xkb file can be dumped with the xkbcomp program.
Instead of using container->width/height as both the input and output
of the layout calculation have container->width_fraction/height_fraction
as the share of the parent this container occupies and calculate the
layout based on that. That way the container arrangement can always be
recalculated even if width/height have been altered by things like
fullscreen.
To do this several parts are reworked:
- The vertical and horizontal arrangement code is ajusted to work with
fractions instead of directly with width/height
- The resize code is then changed to manipulate the fractions when
working on tiled containers.
- Finally the places that manipulated width/height are adjusted to
match. The adjusted parts are container split, swap, and the input
seat code.
It's possible that some parts of the code are now adjusting width and
height only for those to be immediately recalculated. That's harmless
and since non-tiled containers are still sized with width/height
directly it may avoid breaking other corner cases.
Fixes#3547Fixes#4297
This adds checks to the input_manager_libinput_reset_* functions to
only attempt resetting supported options on reload. This should have no
functional difference to the user, but will remove several `Failed to
apply libinput config: Unsupported configuration option` lines from the
log that can be noisy and potential red herrings.
This adds a --reload flag to cmd_bindswitch that allows for the binding
to be executed on reload. One possible use case for this is to allow
users to disable outputs when the lid closes and enable them when the
lid opens without having to open and re-close the lid after a reload.
This adds the logic to defer binding execution while sway is still
initializing. Without this, the binding command would be executed, but
the command handler would return CMD_DEFER, which was being treated as
a failure to run. To avoid partial executions, this will defer all
bindings while config->active is false.
Before the delta input config is stored, this attempts to compile a
keymap with it. If the keymap fails to compile, then the first line of
the xkbcommon log entry will be included with a `CMD_FAILURE`, the
entire xkbcommon log entry will be included in the sway error log, and
the delta will not be stored.
This only handles basic issues such as a layouts not existing. This
will NOT catch more complex issues such as when a variant does
exist, but not for the given layout (ex: `azerty` is a valid variant,
but the `us` layout does not have a `azerty` variant).
Commit 190546fd31 failed to consider the
edge case where xwayland is disabled via the sway config. This leads to
a SEGFAULT when setting the xwayland cursor since the xwayland server is
not running.
New 'seat <name> xcursor_theme <theme> [<size>]' command that
configures the default xcursor theme.
The default seat's xcursor theme is also propagated to XWayland, and
exported through the XCURSOR_THEME and XCURSOR_SIZE environment
variables. This is done every time the default seat's configuration is
changed.
This changes the behavior of bindings to make the `BINDING_LOCKED` flag
conflicting, which will allow for both unlocked and locked bindings.
If there are two matching bindings and one has `--locked` and the other
does not, the one with `--locked` will be preferred when locked and
the one without will be preferred when unlocked.
If there are two matching bindings and one has both a matching
`--input-device=<input>` and `--locked` and the other has neither, the
former will be preferred for both unlocked and locked.
This also refactors `get_active_binding` in `sway/input/keyboard.c`
to make it easier to read.
This just changes the indentation of `sway/input/switch.c` to use
tabs instead of spaces since I messed up and missed it when approving
the PR that added the file.
This attempts to use the default keymap when the one defined in the
input config fails to compile. The goal is to make it so the keyboard
is always in a usable state, even if it is not the user's requested
settings as usability is more important.
This also removes the calls to `getenv` for the `XKB_DEFAULT_*` family
of environment variables. The reasoning is libxkbcommon will fallback
to using those (and then the system defaults) when any of the rule
names are `NULL` or an empty string anyway so there is no need for
sway to duplicate the efforts.
This fixes the criteria for emitting a `bar_state_update` event to
notify swaybar (and any other bars utilizing the event) on whether the
bar is visible by modifier. It is not enough to only emit the event
when both the bar mode and bar hidden state are `hide` since it is
possible to release the modifier while hidden state is `show` and then
change hidden state to `hide` without pressing the modifier. This also
emits the event whenever visible by modifier is set and should no
longer be regardless of the mode and state to ensure that it gets
properly cleared. If visible by modifier is not set and the bar is not
in `hide`/`hide`, then no events will be sent and visible by modifier
will not be set
Add support for configurations that apply to a type of inputs
(i.e. natural scrolling on all touchpads). A type config is
differentiated by a `type:` prefix followed by the type it
corresponds to.
When new devices appear, the device config is merged on top of its
type config (if it exists). New type configs are applied on top of
existing configs.
Use libinput_device_config_tap_get_finger_count to determine whether
a pointer is a touchpad.
swaymsg is also updated to reflect the new touchpad type.
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 commit adds support for laptop lid and tablet
mode switches as provided by evdev/libinput and
handled by wlroots.
Adds a new bindswitch command with syntax:
bindswitch <switch>:<state> <command>
Where <switch> is one of:
tablet for WLR_SWITCH_TYPE_TABLET_MODE
lid for WLR_SWITCH_TYPE_LID
<state> is one of:
on for WLR_SWITCH_STATE_ON
off for WLR_SWITCH_STATE_OFF
toggle for WLR_SWITCH_STATE_TOGGLE
(Note that WLR_SWITCH_STATE_TOGGLE doesn't map to
libinput and will trigger at both on and off events)
Firstly, this fixes a recent regression where having
`focus_follows_mouse yes` and hovering an inactive tab caused it to gain
focus. The code was missing a view_is_visible check.
The code is handling the logic for both focus_follows_mouse yes and
focus_follows_mouse always, where the latter will apply when nudging the
mouse after a workspace switch. However, the view_is_visible check
didn't apply when using focus_follows_mouse always, so hovering a tab
with that configuration would cause is to focus. This was a bug. When
adding the view_is_visible check, it now applies to both yes and always.
Note that the comment about the split container was wrong. At this point
the hovered node cannot be a split container because it passed the
node_is_view check. The comment has been removed.
Lastly, the else condition is completely removed. This didn't appear to
have any practical use. Setting focus to the result of
seat_get_focus_inactive is very likely going to be a no op. There is a
slim chance that this will break something, and if so I'd like to find
out what so it can be properly documented in the code.
This introduces a `default` seat operation which is used when no mouse
buttons are being held. This means there is now always a seat operation
in progress. It allows us to separate `default` code from the standard
cursor management code.
The sway_seatop_impl struct has gained callbacks `axis`, `rebase` and
`end`, and lost callbacks `finish` and `abort`. `axis` and `rebase` are
only used by the default seatop. `end` is called when a seatop is being
replaced by another one and allows the seatop to free any resources,
though no seatop currently needs to do this. `finish` is no longer
required, as each seatop can gracefully finish in their `button`
callback. And `abort` is not needed, as calling `end` would achieve the
same thing. The struct has also gained a bool named allow_set_cursor
which allows the client to set a new cursor during `default` and `down`
seatops.
Seatops would previously store which button they were started with and
stop when that button was released. This behaviour is changed so that it
only ends once all buttons are released. So you can start a drag with
$mod+left, then click and hold right, release left and it'll continue
dragging while the right button is held.
The motion callback now accepts dx and dy. Most seatops don't use this
as they store the cursor position when the seatop is started and compare
it with the current cursor position. This approach doesn't make sense
for the default seatop though, hence why dx and dy are needed.
The pressed_buttons array has been moved from the sway_cursor struct to
the default seatop's data. This is only used for the default seatop to
check bindings. The total pressed button count remains in the
sway_cursor struct though, because all the other seatops check it to
know if they should end.
The `down` seatop no longer has a `moved` property. This was used to
track if the cursor moved and to recheck focus_follows_mouse, but seems
to work without it.
The logic for focus_follows_mouse has been refactored. As part of this
I've removed the call to wlr_seat_keyboard_has_grab as we don't appear
to use keyboard grabs.
The functions for handling relative motion, absolute motion and tool
axis have been changed. Previously the handler functions were
handle_cursor_motion, handle_cursor_motion_absolute and
handle_tool_axis. The latter two both called cursor_motion_absolute.
Both handle_cursor_motion and cursor_motion_absolute did very similar
things. These are now simplified into three handlers and a single common
function called cursor_motion. All three handlers call cursor_motion. As
cursor_motion works with relative distances, the absolute and tool axis
handlers convert them to relative first.
This moves setting `seat->prev_workspace_name` from `workspace_switch`
to `set_workspace`. `workspace_switch` is only called when using a
`workspace` command to change the workspace so any workspace change
based on criteria was not altering `seat->prev_workspace_name`. By
moving it to `set_workspace`, which is called by `seat_set_focus`, it
will change any time focus changes to a node on a different workspace
By the time seatop_allows_events was called, seatop_impl was already
NULL, causing the function to always return false. This means a press
event was sent to clients without a corresponding release event.
This patch moves the call to seatop_finish to after the
seatop_allows_events check.
It turns out sending button events during all seat operations is not
desirable. This patch introduces a new property
`seatop_impl.allows_events` which allows each operation to define
whether button events should be passed to the surface or not.
The `down` seat operation is the only one that supports this. As all the
other seatops don't support it, the calls to seat_pointer_notify_button
prior to starting them have been removed.
If two cursor buttons are pressed at the same time, the client will now
be notified of the second button press.
The main reason for not sending the concurrent presses was due to an
early return in dispatch_cursor_button if a seatop is in progress. This
patch makes it call seat_pointer_notify_button prior to returning. But
it also has to make sure there's not a mismatch in events such as a
release without a press.
Prior to this patch, the down seatop would send press and release events
in its begin and finish functions. No other seatops did this. A press
event would be sent prior to starting tiling drag, but never an
associated release.
After this patch, no seatops send their own press or release events. We
send them prior to calling the seatop begin functions, then the first
part of dispatch_cursor_button handles all presses during seatops and
when releasing the seatop.
This changes the way zero (which is the default) is interpreted for both
the width and height of `floating_maximum_size`. It now refers to the
width and height of the entire output layout, which matches i3's
behavior.
This also removes duplicated code to calculate the floating constraints
in three files. Before this, `container_init_floating` used two-thirds
of the workspace width/height as the max and the entire workspace
width/height was used everywhere else. Now, all callers use a single
function `floating_calculate_constraints`.
All seat operations except "down" eat the button pressed event and don't send
it to clients. Thus, when ending such seat operations we shouldn't send the
button released event.
This commit moves the logic used to send pressed/released into the "down"
operation.
If an unmanaged or layer surface is focused when an output gets
disabled and an empty workspace on the output was focused by the seat,
the seat needs to refocus it's focus inactive to update the value of
`seat->workspace`.
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.
In seatop_move_tiling, it is possible to cause a stack overflow by
dragging a container into one of its descendants. This disables the
ability to move into a descendant.
This allows the focused inactive tree node and visible workspaces to be
changed while a surface layer has focus. The layer temporarily loses
focus, the tree focus changes, and the layer gets refocused.
When moving a descendant of a tabbed or stacked container, it is possible
for the target node to be the node being moved. This causes a segfault in
`handle_finish` since the node will be detached and then attempted to be
attached to it own parent, which is NULL due to the detach. In this
case, the target node should not be set to the node being moved, but the
parent of the node. This also allows for a descendant of a tabbed or
stacked container to be dragged out of the tabs/stacks and to be a
sibling of the tabbbed/stacked container, which was not previously
possible.
In handle_cursor_motion, the timestamp passed to
`wlr_relative_pointer_manager_v1_send_relative_motion` should be
microseconds (not milliseconds) according to relative-pointer-v1 spec.
If `repeat_rate` or `repeat_delay` is set without the other being set,
the default was being used for both. This changes the logic to respect
the value given and use the default for the other when only one is set.
sway-bar(5) documents `modifier none`, which comes from i3. This
implements the functionality for `modifier none` since it was not
previously implemented. The bar modifier toggles visibility of the bar
when the bar mode is set to hide. When the bar modifier is set to
`none`, the ability to toggle visibility of the bar will be disabled.
Since a tablet tool provides the WL_SEAT_CAPABILITY_POINTER capability,
sway will attempt to use the xcursor manager to set a cursor image. If
the tablet tool was the first (and possibly only) device to provide the
capability for the seat, the xcursor manager was not being configured
before attempting to set a cursor image. This was due to
`seat_configure_xcursor` only being called in `seat_configure_pointer`.
Since the xcursor manager was NULL in this case, it would cause a
segfault when attempting to set a cursor image. This adds a call to
`seat_configure_xcursor` in `seat_configure_tablet_tool` to ensure that
the seat has a xcursor manager.
If a seat does not exist in seat_cmd_cursor, do not create it. A seat
without any attachments is useless since it will have no capabilities.
This changes `input_manager_get_seat` to have an additional argument
that dictates whether or not to create the seat if it does not exist.
This changes the `pointer_constraint` command to be a subcommand of seat
to allow for per-seat settings. The current implementation that is not a
seat subcommand will only operate on the current seat and will segfault
in the config due to `config->handler_context.seat` only being set at
runtime.
This also allows for the wildcard identifier to be used to alter the
pointer constraint settings on all seats and allows for the setting to
be merged with the rest of the seat config.
Modifier handling functions were moved into sway/input/keyboard.c;
opposite_direction for enum wlr_direction into sway/tree/output.c;
and get_parent_pid into sway/tree/root.c .
