Introduce default seatop

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.

1 files changed, 629 insertions, 0 deletions

diff --git a/sway/input/seatop_default.c b/sway/input/seatop_default.c
new file mode 100644
index 00000000..fc785cda
--- /dev/null
+++ b/sway/input/seatop_default.c
@@ -0,0 +1,629 @@
+#define _POSIX_C_SOURCE 200809L
+#include <float.h>
+#include <libevdev/libevdev.h>
+#include <wlr/types/wlr_cursor.h>
+#include <wlr/types/wlr_xcursor_manager.h>
+#include "sway/input/cursor.h"
+#include "sway/input/seat.h"
+#include "sway/tree/view.h"
+#include "log.h"
+
+struct seatop_default_event {
+        struct sway_node *previous_node;
+        uint32_t pressed_buttons[SWAY_CURSOR_PRESSED_BUTTONS_CAP];
+        size_t pressed_button_count;
+};
+
+/*-----------------------------------------\
+ * Functions shared by multiple callbacks  /
+ *---------------------------------------*/
+
+/**
+ * Determine if the edge of the given container is on the edge of the
+ * workspace/output.
+ */
+static bool edge_is_external(struct sway_container *cont, enum wlr_edges edge) {
+        enum sway_container_layout layout = L_NONE;
+        switch (edge) {
+        case WLR_EDGE_TOP:
+        case WLR_EDGE_BOTTOM:
+                layout = L_VERT;
+                break;
+        case WLR_EDGE_LEFT:
+        case WLR_EDGE_RIGHT:
+                layout = L_HORIZ;
+                break;
+        case WLR_EDGE_NONE:
+                sway_assert(false, "Never reached");
+                return false;
+        }
+
+        // Iterate the parents until we find one with the layout we want,
+        // then check if the child has siblings between it and the edge.
+        while (cont) {
+                if (container_parent_layout(cont) == layout) {
+                        list_t *siblings = container_get_siblings(cont);
+                        int index = list_find(siblings, cont);
+                        if (index > 0 && (edge == WLR_EDGE_LEFT || edge == WLR_EDGE_TOP)) {
+                                return false;
+                        }
+                        if (index < siblings->length - 1 &&
+                                        (edge == WLR_EDGE_RIGHT || edge == WLR_EDGE_BOTTOM)) {
+                                return false;
+                        }
+                }
+                cont = cont->parent;
+        }
+        return true;
+}
+
+static enum wlr_edges find_edge(struct sway_container *cont,
+                struct sway_cursor *cursor) {
+        if (!cont->view) {
+                return WLR_EDGE_NONE;
+        }
+        if (cont->border == B_NONE || !cont->border_thickness ||
+                        cont->border == B_CSD) {
+                return WLR_EDGE_NONE;
+        }
+
+        enum wlr_edges edge = 0;
+        if (cursor->cursor->x < cont->x + cont->border_thickness) {
+                edge |= WLR_EDGE_LEFT;
+        }
+        if (cursor->cursor->y < cont->y + cont->border_thickness) {
+                edge |= WLR_EDGE_TOP;
+        }
+        if (cursor->cursor->x >= cont->x + cont->width - cont->border_thickness) {
+                edge |= WLR_EDGE_RIGHT;
+        }
+        if (cursor->cursor->y >= cont->y + cont->height - cont->border_thickness) {
+                edge |= WLR_EDGE_BOTTOM;
+        }
+
+        return edge;
+}
+
+/**
+ * If the cursor is over a _resizable_ edge, return the edge.
+ * Edges that can't be resized are edges of the workspace.
+ */
+static enum wlr_edges find_resize_edge(struct sway_container *cont,
+                struct sway_cursor *cursor) {
+        enum wlr_edges edge = find_edge(cont, cursor);
+        if (edge && !container_is_floating(cont) && edge_is_external(cont, edge)) {
+                return WLR_EDGE_NONE;
+        }
+        return edge;
+}
+
+/**
+ * Return the mouse binding which matches modifier, click location, release,
+ * and pressed button state, otherwise return null.
+ */
+static struct sway_binding* get_active_mouse_binding(
+                struct seatop_default_event *e, list_t *bindings, uint32_t modifiers,
+                bool release, bool on_titlebar, bool on_border, bool on_content,
+                bool on_workspace, const char *identifier) {
+        uint32_t click_region =
+                        ((on_titlebar || on_workspace) ? BINDING_TITLEBAR : 0) |
+                        ((on_border || on_workspace) ? BINDING_BORDER : 0) |
+                        ((on_content || on_workspace) ? BINDING_CONTENTS : 0);
+
+        struct sway_binding *current = NULL;
+        for (int i = 0; i < bindings->length; ++i) {
+                struct sway_binding *binding = bindings->items[i];
+                if (modifiers ^ binding->modifiers ||
+                                e->pressed_button_count != (size_t)binding->keys->length ||
+                                release != (binding->flags & BINDING_RELEASE) ||
+                                !(click_region & binding->flags) ||
+                                (on_workspace &&
+                                 (click_region & binding->flags) != click_region) ||
+                                (strcmp(binding->input, identifier) != 0 &&
+                                 strcmp(binding->input, "*") != 0)) {
+                        continue;
+                }
+
+                bool match = true;
+                for (size_t j = 0; j < e->pressed_button_count; j++) {
+                        uint32_t key = *(uint32_t *)binding->keys->items[j];
+                        if (key != e->pressed_buttons[j]) {
+                                match = false;
+                                break;
+                        }
+                }
+                if (!match) {
+                        continue;
+                }
+
+                if (!current || strcmp(current->input, "*") == 0) {
+                        current = binding;
+                        if (strcmp(current->input, identifier) == 0) {
+                                // If a binding is found for the exact input, quit searching
+                                break;
+                        }
+                }
+        }
+        return current;
+}
+
+/**
+ * Remove a button (and duplicates) from the sorted list of currently pressed
+ * buttons.
+ */
+static void state_erase_button(struct seatop_default_event *e,
+                uint32_t button) {
+        size_t j = 0;
+        for (size_t i = 0; i < e->pressed_button_count; ++i) {
+                if (i > j) {
+                        e->pressed_buttons[j] = e->pressed_buttons[i];
+                }
+                if (e->pressed_buttons[i] != button) {
+                        ++j;
+                }
+        }
+        while (e->pressed_button_count > j) {
+                --e->pressed_button_count;
+                e->pressed_buttons[e->pressed_button_count] = 0;
+        }
+}
+
+/**
+ * Add a button to the sorted list of currently pressed buttons, if there
+ * is space.
+ */
+static void state_add_button(struct seatop_default_event *e, uint32_t button) {
+        if (e->pressed_button_count >= SWAY_CURSOR_PRESSED_BUTTONS_CAP) {
+                return;
+        }
+        size_t i = 0;
+        while (i < e->pressed_button_count && e->pressed_buttons[i] < button) {
+                ++i;
+        }
+        size_t j = e->pressed_button_count;
+        while (j > i) {
+                e->pressed_buttons[j] = e->pressed_buttons[j - 1];
+                --j;
+        }
+        e->pressed_buttons[i] = button;
+        e->pressed_button_count++;
+}
+
+static void cursor_do_rebase(struct sway_cursor *cursor, uint32_t time_msec,
+                struct sway_node *node, struct wlr_surface *surface,
+                double sx, double sy) {
+        // Handle cursor image
+        if (surface) {
+                // Reset cursor if switching between clients
+                struct wl_client *client = wl_resource_get_client(surface->resource);
+                if (client != cursor->image_client) {
+                        cursor_set_image(cursor, "left_ptr", client);
+                }
+        } else if (node && node->type == N_CONTAINER) {
+                // Try a node's resize edge
+                enum wlr_edges edge = find_resize_edge(node->sway_container, cursor);
+                if (edge == WLR_EDGE_NONE) {
+                        cursor_set_image(cursor, "left_ptr", NULL);
+                } else if (container_is_floating(node->sway_container)) {
+                        cursor_set_image(cursor, wlr_xcursor_get_resize_name(edge), NULL);
+                } else {
+                        if (edge & (WLR_EDGE_LEFT | WLR_EDGE_RIGHT)) {
+                                cursor_set_image(cursor, "col-resize", NULL);
+                        } else {
+                                cursor_set_image(cursor, "row-resize", NULL);
+                        }
+                }
+        } else {
+                cursor_set_image(cursor, "left_ptr", NULL);
+        }
+
+        // Send pointer enter/leave
+        struct wlr_seat *wlr_seat = cursor->seat->wlr_seat;
+        if (surface) {
+                if (seat_is_input_allowed(cursor->seat, surface)) {
+                        wlr_seat_pointer_notify_enter(wlr_seat, surface, sx, sy);
+                        wlr_seat_pointer_notify_motion(wlr_seat, time_msec, sx, sy);
+                }
+        } else {
+                wlr_seat_pointer_clear_focus(wlr_seat);
+        }
+}
+
+/*----------------------------------\
+ * Functions used by handle_button  /
+ *--------------------------------*/
+
+static void handle_button(struct sway_seat *seat, uint32_t time_msec,
+                struct wlr_input_device *device, uint32_t button,
+                enum wlr_button_state state) {
+        struct seatop_default_event *e = seat->seatop_data;
+        struct sway_cursor *cursor = seat->cursor;
+
+        // Determine what's under the cursor
+        struct wlr_surface *surface = NULL;
+        double sx, sy;
+        struct sway_node *node = node_at_coords(seat,
+                        cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+        struct sway_container *cont = node && node->type == N_CONTAINER ?
+                node->sway_container : NULL;
+        bool is_floating = cont && container_is_floating(cont);
+        bool is_floating_or_child = cont && container_is_floating_or_child(cont);
+        bool is_fullscreen_or_child = cont && container_is_fullscreen_or_child(cont);
+        enum wlr_edges edge = cont ? find_edge(cont, cursor) : WLR_EDGE_NONE;
+        enum wlr_edges resize_edge = edge ?
+                find_resize_edge(cont, cursor) : WLR_EDGE_NONE;
+        bool on_border = edge != WLR_EDGE_NONE;
+        bool on_contents = cont && !on_border && surface;
+        bool on_workspace = node && node->type == N_WORKSPACE;
+        bool on_titlebar = cont && !on_border && !surface;
+
+        // Handle mouse bindings
+        struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat->wlr_seat);
+        uint32_t modifiers = keyboard ? wlr_keyboard_get_modifiers(keyboard) : 0;
+
+        char *device_identifier = device ? input_device_get_identifier(device)
+                : strdup("*");
+        struct sway_binding *binding = NULL;
+        if (state == WLR_BUTTON_PRESSED) {
+                state_add_button(e, button);
+                binding = get_active_mouse_binding(e,
+                        config->current_mode->mouse_bindings, modifiers, false,
+                        on_titlebar, on_border, on_contents, on_workspace,
+                        device_identifier);
+        } else {
+                binding = get_active_mouse_binding(e,
+                        config->current_mode->mouse_bindings, modifiers, true,
+                        on_titlebar, on_border, on_contents, on_workspace,
+                        device_identifier);
+                state_erase_button(e, button);
+        }
+        free(device_identifier);
+        if (binding) {
+                seat_execute_command(seat, binding);
+                return;
+        }
+
+        // Handle clicking an empty workspace
+        if (node && node->type == N_WORKSPACE) {
+                seat_set_focus(seat, node);
+                return;
+        }
+
+        // Handle clicking a layer surface
+        if (surface && wlr_surface_is_layer_surface(surface)) {
+                struct wlr_layer_surface_v1 *layer =
+                        wlr_layer_surface_v1_from_wlr_surface(surface);
+                if (layer->current.keyboard_interactive) {
+                        seat_set_focus_layer(seat, layer);
+                }
+                seat_pointer_notify_button(seat, time_msec, button, state);
+                return;
+        }
+
+        // Handle tiling resize via border
+        if (cont && resize_edge && button == BTN_LEFT &&
+                        state == WLR_BUTTON_PRESSED && !is_floating) {
+                seat_set_focus_container(seat, cont);
+                seatop_begin_resize_tiling(seat, cont, edge);
+                return;
+        }
+
+        // Handle tiling resize via mod
+        bool mod_pressed = keyboard &&
+                (wlr_keyboard_get_modifiers(keyboard) & config->floating_mod);
+        if (cont && !is_floating_or_child && mod_pressed &&
+                        state == WLR_BUTTON_PRESSED) {
+                uint32_t btn_resize = config->floating_mod_inverse ?
+                        BTN_LEFT : BTN_RIGHT;
+                if (button == btn_resize) {
+                        edge = 0;
+                        edge |= cursor->cursor->x > cont->x + cont->width / 2 ?
+                                WLR_EDGE_RIGHT : WLR_EDGE_LEFT;
+                        edge |= cursor->cursor->y > cont->y + cont->height / 2 ?
+                                WLR_EDGE_BOTTOM : WLR_EDGE_TOP;
+
+                        const char *image = NULL;
+                        if (edge == (WLR_EDGE_LEFT | WLR_EDGE_TOP)) {
+                                image = "nw-resize";
+                        } else if (edge == (WLR_EDGE_TOP | WLR_EDGE_RIGHT)) {
+                                image = "ne-resize";
+                        } else if (edge == (WLR_EDGE_RIGHT | WLR_EDGE_BOTTOM)) {
+                                image = "se-resize";
+                        } else if (edge == (WLR_EDGE_BOTTOM | WLR_EDGE_LEFT)) {
+                                image = "sw-resize";
+                        }
+                        cursor_set_image(seat->cursor, image, NULL);
+                        seat_set_focus_container(seat, cont);
+                        seatop_begin_resize_tiling(seat, cont, edge);
+                        return;
+                }
+        }
+
+        // Handle beginning floating move
+        if (cont && is_floating_or_child && !is_fullscreen_or_child &&
+                        state == WLR_BUTTON_PRESSED) {
+                uint32_t btn_move = config->floating_mod_inverse ? BTN_RIGHT : BTN_LEFT;
+                if (button == btn_move && state == WLR_BUTTON_PRESSED &&
+                                (mod_pressed || on_titlebar)) {
+                        while (cont->parent) {
+                                cont = cont->parent;
+                        }
+                        seat_set_focus_container(seat, cont);
+                        seatop_begin_move_floating(seat, cont);
+                        return;
+                }
+        }
+
+        // Handle beginning floating resize
+        if (cont && is_floating_or_child && !is_fullscreen_or_child &&
+                        state == WLR_BUTTON_PRESSED) {
+                // Via border
+                if (button == BTN_LEFT && resize_edge != WLR_EDGE_NONE) {
+                        seatop_begin_resize_floating(seat, cont, resize_edge);
+                        return;
+                }
+
+                // Via mod+click
+                uint32_t btn_resize = config->floating_mod_inverse ?
+                        BTN_LEFT : BTN_RIGHT;
+                if (mod_pressed && button == btn_resize) {
+                        struct sway_container *floater = cont;
+                        while (floater->parent) {
+                                floater = floater->parent;
+                        }
+                        edge = 0;
+                        edge |= cursor->cursor->x > floater->x + floater->width / 2 ?
+                                WLR_EDGE_RIGHT : WLR_EDGE_LEFT;
+                        edge |= cursor->cursor->y > floater->y + floater->height / 2 ?
+                                WLR_EDGE_BOTTOM : WLR_EDGE_TOP;
+                        seatop_begin_resize_floating(seat, floater, edge);
+                        return;
+                }
+        }
+
+        // Handle moving a tiling container
+        if (config->tiling_drag && (mod_pressed || on_titlebar) &&
+                        state == WLR_BUTTON_PRESSED && !is_floating_or_child &&
+                        cont && cont->fullscreen_mode == FULLSCREEN_NONE) {
+                struct sway_container *focus = seat_get_focused_container(seat);
+                bool focused = focus == cont || container_has_ancestor(focus, cont);
+                if (on_titlebar && !focused) {
+                        node = seat_get_focus_inactive(seat, &cont->node);
+                        seat_set_focus(seat, node);
+                }
+
+                // If moving a container by it's title bar, use a threshold for the drag
+                if (!mod_pressed && config->tiling_drag_threshold > 0) {
+                        seatop_begin_move_tiling_threshold(seat, cont);
+                } else {
+                        seatop_begin_move_tiling(seat, cont);
+                }
+                return;
+        }
+
+        // Handle mousedown on a container surface
+        if (surface && cont && state == WLR_BUTTON_PRESSED) {
+                seat_set_focus_container(seat, cont);
+                seatop_begin_down(seat, cont, time_msec, sx, sy);
+                seat_pointer_notify_button(seat, time_msec, button, WLR_BUTTON_PRESSED);
+                return;
+        }
+
+        // Handle clicking a container surface or decorations
+        if (cont) {
+                node = seat_get_focus_inactive(seat, &cont->node);
+                seat_set_focus(seat, node);
+                seat_pointer_notify_button(seat, time_msec, button, state);
+                return;
+        }
+
+        seat_pointer_notify_button(seat, time_msec, button, state);
+}
+
+/*----------------------------------\
+ * Functions used by handle_motion  /
+ *--------------------------------*/
+
+static void check_focus_follows_mouse(struct sway_seat *seat,
+                struct seatop_default_event *e, struct sway_node *hovered_node) {
+        struct sway_node *focus = seat_get_focus(seat);
+
+        // If a workspace node is hovered (eg. in the gap area), only set focus if
+        // the workspace is on a different output to the previous focus.
+        if (focus && hovered_node->type == N_WORKSPACE) {
+                struct sway_output *focused_output = node_get_output(focus);
+                struct sway_output *hovered_output = node_get_output(hovered_node);
+                if (hovered_output != focused_output) {
+                        seat_set_focus(seat, seat_get_focus_inactive(seat, hovered_node));
+                }
+                return;
+        }
+
+        if (node_is_view(hovered_node)) {
+                if (hovered_node != e->previous_node ||
+                                config->focus_follows_mouse == FOLLOWS_ALWAYS) {
+                        seat_set_focus(seat, hovered_node);
+                } else {
+                        // Focusing a tab which contains a split child
+                        struct sway_node *next_focus =
+                                seat_get_focus_inactive(seat, &root->node);
+                        if (next_focus && node_is_view(next_focus) &&
+                                        view_is_visible(next_focus->sway_container->view)) {
+                                seat_set_focus(seat, next_focus);
+                        }
+                }
+        }
+}
+
+static void handle_motion(struct sway_seat *seat, uint32_t time_msec,
+                double dx, double dy) {
+        struct seatop_default_event *e = seat->seatop_data;
+        struct sway_cursor *cursor = seat->cursor;
+
+        struct wlr_surface *surface = NULL;
+        double sx, sy;
+        struct sway_node *node = node_at_coords(seat,
+                        cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+
+        if (node && config->focus_follows_mouse != FOLLOWS_NO) {
+                check_focus_follows_mouse(seat, e, node);
+        }
+
+        cursor_do_rebase(cursor, time_msec, node, surface, sx, sy);
+
+        struct sway_drag_icon *drag_icon;
+        wl_list_for_each(drag_icon, &root->drag_icons, link) {
+                if (drag_icon->seat == seat) {
+                        drag_icon_update_position(drag_icon);
+                }
+        }
+
+        e->previous_node = node;
+}
+
+/*--------------------------------\
+ * Functions used by handle_axis  /
+ *------------------------------*/
+
+static uint32_t wl_axis_to_button(struct wlr_event_pointer_axis *event) {
+        switch (event->orientation) {
+        case WLR_AXIS_ORIENTATION_VERTICAL:
+                return event->delta < 0 ? SWAY_SCROLL_UP : SWAY_SCROLL_DOWN;
+        case WLR_AXIS_ORIENTATION_HORIZONTAL:
+                return event->delta < 0 ? SWAY_SCROLL_LEFT : SWAY_SCROLL_RIGHT;
+        default:
+                sway_log(SWAY_DEBUG, "Unknown axis orientation");
+                return 0;
+        }
+}
+
+static void handle_axis(struct sway_seat *seat,
+                struct wlr_event_pointer_axis *event) {
+        struct sway_input_device *input_device =
+                event->device ? event->device->data : NULL;
+        struct input_config *ic =
+                input_device ? input_device_get_config(input_device) : NULL;
+        struct sway_cursor *cursor = seat->cursor;
+        struct seatop_default_event *e = seat->seatop_data;
+
+        // Determine what's under the cursor
+        struct wlr_surface *surface = NULL;
+        double sx, sy;
+        struct sway_node *node = node_at_coords(seat,
+                        cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+        struct sway_container *cont = node && node->type == N_CONTAINER ?
+                node->sway_container : NULL;
+        enum wlr_edges edge = cont ? find_edge(cont, cursor) : WLR_EDGE_NONE;
+        bool on_border = edge != WLR_EDGE_NONE;
+        bool on_titlebar = cont && !on_border && !surface;
+        bool on_titlebar_border = cont && on_border &&
+                cursor->cursor->y < cont->content_y;
+        bool on_contents = cont && !on_border && surface;
+        bool on_workspace = node && node->type == N_WORKSPACE;
+        float scroll_factor =
+                (ic == NULL || ic->scroll_factor == FLT_MIN) ? 1.0f : ic->scroll_factor;
+
+        bool handled = false;
+
+        // Gather information needed for mouse bindings
+        struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat->wlr_seat);
+        uint32_t modifiers = keyboard ? wlr_keyboard_get_modifiers(keyboard) : 0;
+        struct wlr_input_device *device =
+                input_device ? input_device->wlr_device : NULL;
+        char *dev_id = device ? input_device_get_identifier(device) : strdup("*");
+        uint32_t button = wl_axis_to_button(event);
+
+        // Handle mouse bindings - x11 mouse buttons 4-7 - press event
+        struct sway_binding *binding = NULL;
+        state_add_button(e, button);
+        binding = get_active_mouse_binding(e, config->current_mode->mouse_bindings,
+                        modifiers, false, on_titlebar, on_border, on_contents, on_workspace,
+                        dev_id);
+        if (binding) {
+                seat_execute_command(seat, binding);
+                handled = true;
+        }
+
+        // Scrolling on a tabbed or stacked title bar (handled as press event)
+        if (!handled && (on_titlebar || on_titlebar_border)) {
+                enum sway_container_layout layout = container_parent_layout(cont);
+                if (layout == L_TABBED || layout == L_STACKED) {
+                        struct sway_node *tabcontainer = node_get_parent(node);
+                        struct sway_node *active =
+                                seat_get_active_tiling_child(seat, tabcontainer);
+                        list_t *siblings = container_get_siblings(cont);
+                        int desired = list_find(siblings, active->sway_container) +
+                                round(scroll_factor * event->delta_discrete);
+                        if (desired < 0) {
+                                desired = 0;
+                        } else if (desired >= siblings->length) {
+                                desired = siblings->length - 1;
+                        }
+                        struct sway_node *old_focus = seat_get_focus(seat);
+                        struct sway_container *new_sibling_con = siblings->items[desired];
+                        struct sway_node *new_sibling = &new_sibling_con->node;
+                        struct sway_node *new_focus =
+                                seat_get_focus_inactive(seat, new_sibling);
+                        if (node_has_ancestor(old_focus, tabcontainer)) {
+                                seat_set_focus(seat, new_focus);
+                        } else {
+                                // Scrolling when focus is not in the tabbed container at all
+                                seat_set_raw_focus(seat, new_sibling);
+                                seat_set_raw_focus(seat, new_focus);
+                                seat_set_raw_focus(seat, old_focus);
+                        }
+                        handled = true;
+                }
+        }
+
+        // Handle mouse bindings - x11 mouse buttons 4-7 - release event
+        binding = get_active_mouse_binding(e, config->current_mode->mouse_bindings,
+                        modifiers, true, on_titlebar, on_border, on_contents, on_workspace,
+                        dev_id);
+        state_erase_button(e, button);
+        if (binding) {
+                seat_execute_command(seat, binding);
+                handled = true;
+        }
+        free(dev_id);
+
+        if (!handled) {
+                wlr_seat_pointer_notify_axis(cursor->seat->wlr_seat, event->time_msec,
+                        event->orientation, scroll_factor * event->delta,
+                        round(scroll_factor * event->delta_discrete), event->source);
+        }
+}
+
+/*----------------------------------\
+ * Functions used by handle_rebase  /
+ *--------------------------------*/
+
+static void handle_rebase(struct sway_seat *seat, uint32_t time_msec) {
+        struct seatop_default_event *e = seat->seatop_data;
+        struct sway_cursor *cursor = seat->cursor;
+        struct wlr_surface *surface = NULL;
+        double sx = 0.0, sy = 0.0;
+        e->previous_node = node_at_coords(seat,
+                        cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+        cursor_do_rebase(cursor, time_msec, e->previous_node, surface, sx, sy);
+}
+
+static const struct sway_seatop_impl seatop_impl = {
+        .button = handle_button,
+        .motion = handle_motion,
+        .axis = handle_axis,
+        .rebase = handle_rebase,
+        .allow_set_cursor = true,
+};
+
+void seatop_begin_default(struct sway_seat *seat) {
+        seatop_end(seat);
+
+        struct seatop_default_event *e =
+                calloc(1, sizeof(struct seatop_default_event));
+        sway_assert(e, "Unable to allocate seatop_default_event");
+        seat->seatop_impl = &seatop_impl;
+        seat->seatop_data = e;
+
+        seatop_rebase(seat, 0);
+}