wlroots/tinywl/tinywl.c

1009 lines
38 KiB
C

#define _POSIX_C_SOURCE 200112L
#include <assert.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <unistd.h>
#include <wayland-server-core.h>
#include <wlr/backend.h>
#include <wlr/render/allocator.h>
#include <wlr/render/wlr_renderer.h>
#include <wlr/types/wlr_cursor.h>
#include <wlr/types/wlr_compositor.h>
#include <wlr/types/wlr_data_device.h>
#include <wlr/types/wlr_input_device.h>
#include <wlr/types/wlr_keyboard.h>
#include <wlr/types/wlr_output.h>
#include <wlr/types/wlr_output_layout.h>
#include <wlr/types/wlr_pointer.h>
#include <wlr/types/wlr_scene.h>
#include <wlr/types/wlr_seat.h>
#include <wlr/types/wlr_subcompositor.h>
#include <wlr/types/wlr_xcursor_manager.h>
#include <wlr/types/wlr_xdg_shell.h>
#include <wlr/util/log.h>
#include <xkbcommon/xkbcommon.h>
/* For brevity's sake, struct members are annotated where they are used. */
enum tinywl_cursor_mode {
TINYWL_CURSOR_PASSTHROUGH,
TINYWL_CURSOR_MOVE,
TINYWL_CURSOR_RESIZE,
};
struct tinywl_server {
struct wl_display *wl_display;
struct wlr_backend *backend;
struct wlr_renderer *renderer;
struct wlr_allocator *allocator;
struct wlr_scene *scene;
struct wlr_xdg_shell *xdg_shell;
struct wl_listener new_xdg_surface;
struct wl_list views;
struct wlr_cursor *cursor;
struct wlr_xcursor_manager *cursor_mgr;
struct wl_listener cursor_motion;
struct wl_listener cursor_motion_absolute;
struct wl_listener cursor_button;
struct wl_listener cursor_axis;
struct wl_listener cursor_frame;
struct wlr_seat *seat;
struct wl_listener new_input;
struct wl_listener request_cursor;
struct wl_listener request_set_selection;
struct wl_list keyboards;
enum tinywl_cursor_mode cursor_mode;
struct tinywl_view *grabbed_view;
double grab_x, grab_y;
struct wlr_box grab_geobox;
uint32_t resize_edges;
struct wlr_output_layout *output_layout;
struct wl_list outputs;
struct wl_listener new_output;
};
struct tinywl_output {
struct wl_list link;
struct tinywl_server *server;
struct wlr_output *wlr_output;
struct wl_listener frame;
struct wl_listener request_state;
struct wl_listener destroy;
};
struct tinywl_view {
struct wl_list link;
struct tinywl_server *server;
struct wlr_xdg_toplevel *xdg_toplevel;
struct wlr_scene_tree *scene_tree;
struct wl_listener map;
struct wl_listener unmap;
struct wl_listener destroy;
struct wl_listener request_move;
struct wl_listener request_resize;
struct wl_listener request_maximize;
struct wl_listener request_fullscreen;
};
struct tinywl_keyboard {
struct wl_list link;
struct tinywl_server *server;
struct wlr_keyboard *wlr_keyboard;
struct wl_listener modifiers;
struct wl_listener key;
struct wl_listener destroy;
};
static void focus_view(struct tinywl_view *view, struct wlr_surface *surface) {
/* Note: this function only deals with keyboard focus. */
if (view == NULL) {
return;
}
struct tinywl_server *server = view->server;
struct wlr_seat *seat = server->seat;
struct wlr_surface *prev_surface = seat->keyboard_state.focused_surface;
if (prev_surface == surface) {
/* Don't re-focus an already focused surface. */
return;
}
if (prev_surface) {
/*
* Deactivate the previously focused surface. This lets the client know
* it no longer has focus and the client will repaint accordingly, e.g.
* stop displaying a caret.
*/
struct wlr_xdg_surface *previous =
wlr_xdg_surface_try_from_wlr_surface(seat->keyboard_state.focused_surface);
assert(previous != NULL && previous->role == WLR_XDG_SURFACE_ROLE_TOPLEVEL);
wlr_xdg_toplevel_set_activated(previous->toplevel, false);
}
struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat);
/* Move the view to the front */
wlr_scene_node_raise_to_top(&view->scene_tree->node);
wl_list_remove(&view->link);
wl_list_insert(&server->views, &view->link);
/* Activate the new surface */
wlr_xdg_toplevel_set_activated(view->xdg_toplevel, true);
/*
* Tell the seat to have the keyboard enter this surface. wlroots will keep
* track of this and automatically send key events to the appropriate
* clients without additional work on your part.
*/
if (keyboard != NULL) {
wlr_seat_keyboard_notify_enter(seat, view->xdg_toplevel->base->surface,
keyboard->keycodes, keyboard->num_keycodes, &keyboard->modifiers);
}
}
static void keyboard_handle_modifiers(
struct wl_listener *listener, void *data) {
/* This event is raised when a modifier key, such as shift or alt, is
* pressed. We simply communicate this to the client. */
struct tinywl_keyboard *keyboard =
wl_container_of(listener, keyboard, modifiers);
/*
* A seat can only have one keyboard, but this is a limitation of the
* Wayland protocol - not wlroots. We assign all connected keyboards to the
* same seat. You can swap out the underlying wlr_keyboard like this and
* wlr_seat handles this transparently.
*/
wlr_seat_set_keyboard(keyboard->server->seat, keyboard->wlr_keyboard);
/* Send modifiers to the client. */
wlr_seat_keyboard_notify_modifiers(keyboard->server->seat,
&keyboard->wlr_keyboard->modifiers);
}
static bool handle_keybinding(struct tinywl_server *server, xkb_keysym_t sym) {
/*
* Here we handle compositor keybindings. This is when the compositor is
* processing keys, rather than passing them on to the client for its own
* processing.
*
* This function assumes Alt is held down.
*/
switch (sym) {
case XKB_KEY_Escape:
wl_display_terminate(server->wl_display);
break;
case XKB_KEY_F1:
/* Cycle to the next view */
if (wl_list_length(&server->views) < 2) {
break;
}
struct tinywl_view *next_view = wl_container_of(
server->views.prev, next_view, link);
focus_view(next_view, next_view->xdg_toplevel->base->surface);
break;
default:
return false;
}
return true;
}
static void keyboard_handle_key(
struct wl_listener *listener, void *data) {
/* This event is raised when a key is pressed or released. */
struct tinywl_keyboard *keyboard =
wl_container_of(listener, keyboard, key);
struct tinywl_server *server = keyboard->server;
struct wlr_keyboard_key_event *event = data;
struct wlr_seat *seat = server->seat;
/* Translate libinput keycode -> xkbcommon */
uint32_t keycode = event->keycode + 8;
/* Get a list of keysyms based on the keymap for this keyboard */
const xkb_keysym_t *syms;
int nsyms = xkb_state_key_get_syms(
keyboard->wlr_keyboard->xkb_state, keycode, &syms);
bool handled = false;
uint32_t modifiers = wlr_keyboard_get_modifiers(keyboard->wlr_keyboard);
if ((modifiers & WLR_MODIFIER_ALT) &&
event->state == WL_KEYBOARD_KEY_STATE_PRESSED) {
/* If alt is held down and this button was _pressed_, we attempt to
* process it as a compositor keybinding. */
for (int i = 0; i < nsyms; i++) {
handled = handle_keybinding(server, syms[i]);
}
}
if (!handled) {
/* Otherwise, we pass it along to the client. */
wlr_seat_set_keyboard(seat, keyboard->wlr_keyboard);
wlr_seat_keyboard_notify_key(seat, event->time_msec,
event->keycode, event->state);
}
}
static void keyboard_handle_destroy(struct wl_listener *listener, void *data) {
/* This event is raised by the keyboard base wlr_input_device to signal
* the destruction of the wlr_keyboard. It will no longer receive events
* and should be destroyed.
*/
struct tinywl_keyboard *keyboard =
wl_container_of(listener, keyboard, destroy);
wl_list_remove(&keyboard->modifiers.link);
wl_list_remove(&keyboard->key.link);
wl_list_remove(&keyboard->destroy.link);
wl_list_remove(&keyboard->link);
free(keyboard);
}
static void server_new_keyboard(struct tinywl_server *server,
struct wlr_input_device *device) {
struct wlr_keyboard *wlr_keyboard = wlr_keyboard_from_input_device(device);
struct tinywl_keyboard *keyboard =
calloc(1, sizeof(struct tinywl_keyboard));
keyboard->server = server;
keyboard->wlr_keyboard = wlr_keyboard;
/* We need to prepare an XKB keymap and assign it to the keyboard. This
* assumes the defaults (e.g. layout = "us"). */
struct xkb_context *context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
struct xkb_keymap *keymap = xkb_keymap_new_from_names(context, NULL,
XKB_KEYMAP_COMPILE_NO_FLAGS);
wlr_keyboard_set_keymap(wlr_keyboard, keymap);
xkb_keymap_unref(keymap);
xkb_context_unref(context);
wlr_keyboard_set_repeat_info(wlr_keyboard, 25, 600);
/* Here we set up listeners for keyboard events. */
keyboard->modifiers.notify = keyboard_handle_modifiers;
wl_signal_add(&wlr_keyboard->events.modifiers, &keyboard->modifiers);
keyboard->key.notify = keyboard_handle_key;
wl_signal_add(&wlr_keyboard->events.key, &keyboard->key);
keyboard->destroy.notify = keyboard_handle_destroy;
wl_signal_add(&device->events.destroy, &keyboard->destroy);
wlr_seat_set_keyboard(server->seat, keyboard->wlr_keyboard);
/* And add the keyboard to our list of keyboards */
wl_list_insert(&server->keyboards, &keyboard->link);
}
static void server_new_pointer(struct tinywl_server *server,
struct wlr_input_device *device) {
/* We don't do anything special with pointers. All of our pointer handling
* is proxied through wlr_cursor. On another compositor, you might take this
* opportunity to do libinput configuration on the device to set
* acceleration, etc. */
wlr_cursor_attach_input_device(server->cursor, device);
}
static void server_new_input(struct wl_listener *listener, void *data) {
/* This event is raised by the backend when a new input device becomes
* available. */
struct tinywl_server *server =
wl_container_of(listener, server, new_input);
struct wlr_input_device *device = data;
switch (device->type) {
case WLR_INPUT_DEVICE_KEYBOARD:
server_new_keyboard(server, device);
break;
case WLR_INPUT_DEVICE_POINTER:
server_new_pointer(server, device);
break;
default:
break;
}
/* We need to let the wlr_seat know what our capabilities are, which is
* communiciated to the client. In TinyWL we always have a cursor, even if
* there are no pointer devices, so we always include that capability. */
uint32_t caps = WL_SEAT_CAPABILITY_POINTER;
if (!wl_list_empty(&server->keyboards)) {
caps |= WL_SEAT_CAPABILITY_KEYBOARD;
}
wlr_seat_set_capabilities(server->seat, caps);
}
static void seat_request_cursor(struct wl_listener *listener, void *data) {
struct tinywl_server *server = wl_container_of(
listener, server, request_cursor);
/* This event is raised by the seat when a client provides a cursor image */
struct wlr_seat_pointer_request_set_cursor_event *event = data;
struct wlr_seat_client *focused_client =
server->seat->pointer_state.focused_client;
/* This can be sent by any client, so we check to make sure this one is
* actually has pointer focus first. */
if (focused_client == event->seat_client) {
/* Once we've vetted the client, we can tell the cursor to use the
* provided surface as the cursor image. It will set the hardware cursor
* on the output that it's currently on and continue to do so as the
* cursor moves between outputs. */
wlr_cursor_set_surface(server->cursor, event->surface,
event->hotspot_x, event->hotspot_y);
}
}
static void seat_request_set_selection(struct wl_listener *listener, void *data) {
/* This event is raised by the seat when a client wants to set the selection,
* usually when the user copies something. wlroots allows compositors to
* ignore such requests if they so choose, but in tinywl we always honor
*/
struct tinywl_server *server = wl_container_of(
listener, server, request_set_selection);
struct wlr_seat_request_set_selection_event *event = data;
wlr_seat_set_selection(server->seat, event->source, event->serial);
}
static struct tinywl_view *desktop_view_at(
struct tinywl_server *server, double lx, double ly,
struct wlr_surface **surface, double *sx, double *sy) {
/* This returns the topmost node in the scene at the given layout coords.
* we only care about surface nodes as we are specifically looking for a
* surface in the surface tree of a tinywl_view. */
struct wlr_scene_node *node = wlr_scene_node_at(
&server->scene->tree.node, lx, ly, sx, sy);
if (node == NULL || node->type != WLR_SCENE_NODE_BUFFER) {
return NULL;
}
struct wlr_scene_buffer *scene_buffer = wlr_scene_buffer_from_node(node);
struct wlr_scene_surface *scene_surface =
wlr_scene_surface_from_buffer(scene_buffer);
if (!scene_surface) {
return NULL;
}
*surface = scene_surface->surface;
/* Find the node corresponding to the tinywl_view at the root of this
* surface tree, it is the only one for which we set the data field. */
struct wlr_scene_tree *tree = node->parent;
while (tree != NULL && tree->node.data == NULL) {
tree = tree->node.parent;
}
return tree->node.data;
}
static void reset_cursor_mode(struct tinywl_server *server) {
/* Reset the cursor mode to passthrough. */
server->cursor_mode = TINYWL_CURSOR_PASSTHROUGH;
server->grabbed_view = NULL;
}
static void process_cursor_move(struct tinywl_server *server, uint32_t time) {
/* Move the grabbed view to the new position. */
struct tinywl_view *view = server->grabbed_view;
wlr_scene_node_set_position(&view->scene_tree->node,
server->cursor->x - server->grab_x,
server->cursor->y - server->grab_y);
}
static void process_cursor_resize(struct tinywl_server *server, uint32_t time) {
/*
* Resizing the grabbed view can be a little bit complicated, because we
* could be resizing from any corner or edge. This not only resizes the view
* on one or two axes, but can also move the view if you resize from the top
* or left edges (or top-left corner).
*
* Note that I took some shortcuts here. In a more fleshed-out compositor,
* you'd wait for the client to prepare a buffer at the new size, then
* commit any movement that was prepared.
*/
struct tinywl_view *view = server->grabbed_view;
double border_x = server->cursor->x - server->grab_x;
double border_y = server->cursor->y - server->grab_y;
int new_left = server->grab_geobox.x;
int new_right = server->grab_geobox.x + server->grab_geobox.width;
int new_top = server->grab_geobox.y;
int new_bottom = server->grab_geobox.y + server->grab_geobox.height;
if (server->resize_edges & WLR_EDGE_TOP) {
new_top = border_y;
if (new_top >= new_bottom) {
new_top = new_bottom - 1;
}
} else if (server->resize_edges & WLR_EDGE_BOTTOM) {
new_bottom = border_y;
if (new_bottom <= new_top) {
new_bottom = new_top + 1;
}
}
if (server->resize_edges & WLR_EDGE_LEFT) {
new_left = border_x;
if (new_left >= new_right) {
new_left = new_right - 1;
}
} else if (server->resize_edges & WLR_EDGE_RIGHT) {
new_right = border_x;
if (new_right <= new_left) {
new_right = new_left + 1;
}
}
struct wlr_box geo_box;
wlr_xdg_surface_get_geometry(view->xdg_toplevel->base, &geo_box);
wlr_scene_node_set_position(&view->scene_tree->node,
new_left - geo_box.x, new_top - geo_box.y);
int new_width = new_right - new_left;
int new_height = new_bottom - new_top;
wlr_xdg_toplevel_set_size(view->xdg_toplevel, new_width, new_height);
}
static void process_cursor_motion(struct tinywl_server *server, uint32_t time) {
/* If the mode is non-passthrough, delegate to those functions. */
if (server->cursor_mode == TINYWL_CURSOR_MOVE) {
process_cursor_move(server, time);
return;
} else if (server->cursor_mode == TINYWL_CURSOR_RESIZE) {
process_cursor_resize(server, time);
return;
}
/* Otherwise, find the view under the pointer and send the event along. */
double sx, sy;
struct wlr_seat *seat = server->seat;
struct wlr_surface *surface = NULL;
struct tinywl_view *view = desktop_view_at(server,
server->cursor->x, server->cursor->y, &surface, &sx, &sy);
if (!view) {
/* If there's no view under the cursor, set the cursor image to a
* default. This is what makes the cursor image appear when you move it
* around the screen, not over any views. */
wlr_xcursor_manager_set_cursor_image(
server->cursor_mgr, "default", server->cursor);
}
if (surface) {
/*
* Send pointer enter and motion events.
*
* The enter event gives the surface "pointer focus", which is distinct
* from keyboard focus. You get pointer focus by moving the pointer over
* a window.
*
* Note that wlroots will avoid sending duplicate enter/motion events if
* the surface has already has pointer focus or if the client is already
* aware of the coordinates passed.
*/
wlr_seat_pointer_notify_enter(seat, surface, sx, sy);
wlr_seat_pointer_notify_motion(seat, time, sx, sy);
} else {
/* Clear pointer focus so future button events and such are not sent to
* the last client to have the cursor over it. */
wlr_seat_pointer_clear_focus(seat);
}
}
static void server_cursor_motion(struct wl_listener *listener, void *data) {
/* This event is forwarded by the cursor when a pointer emits a _relative_
* pointer motion event (i.e. a delta) */
struct tinywl_server *server =
wl_container_of(listener, server, cursor_motion);
struct wlr_pointer_motion_event *event = data;
/* The cursor doesn't move unless we tell it to. The cursor automatically
* handles constraining the motion to the output layout, as well as any
* special configuration applied for the specific input device which
* generated the event. You can pass NULL for the device if you want to move
* the cursor around without any input. */
wlr_cursor_move(server->cursor, &event->pointer->base,
event->delta_x, event->delta_y);
process_cursor_motion(server, event->time_msec);
}
static void server_cursor_motion_absolute(
struct wl_listener *listener, void *data) {
/* This event is forwarded by the cursor when a pointer emits an _absolute_
* motion event, from 0..1 on each axis. This happens, for example, when
* wlroots is running under a Wayland window rather than KMS+DRM, and you
* move the mouse over the window. You could enter the window from any edge,
* so we have to warp the mouse there. There is also some hardware which
* emits these events. */
struct tinywl_server *server =
wl_container_of(listener, server, cursor_motion_absolute);
struct wlr_pointer_motion_absolute_event *event = data;
wlr_cursor_warp_absolute(server->cursor, &event->pointer->base, event->x,
event->y);
process_cursor_motion(server, event->time_msec);
}
static void server_cursor_button(struct wl_listener *listener, void *data) {
/* This event is forwarded by the cursor when a pointer emits a button
* event. */
struct tinywl_server *server =
wl_container_of(listener, server, cursor_button);
struct wlr_pointer_button_event *event = data;
/* Notify the client with pointer focus that a button press has occurred */
wlr_seat_pointer_notify_button(server->seat,
event->time_msec, event->button, event->state);
double sx, sy;
struct wlr_surface *surface = NULL;
struct tinywl_view *view = desktop_view_at(server,
server->cursor->x, server->cursor->y, &surface, &sx, &sy);
if (event->state == WLR_BUTTON_RELEASED) {
/* If you released any buttons, we exit interactive move/resize mode. */
reset_cursor_mode(server);
} else {
/* Focus that client if the button was _pressed_ */
focus_view(view, surface);
}
}
static void server_cursor_axis(struct wl_listener *listener, void *data) {
/* This event is forwarded by the cursor when a pointer emits an axis event,
* for example when you move the scroll wheel. */
struct tinywl_server *server =
wl_container_of(listener, server, cursor_axis);
struct wlr_pointer_axis_event *event = data;
/* Notify the client with pointer focus of the axis event. */
wlr_seat_pointer_notify_axis(server->seat,
event->time_msec, event->orientation, event->delta,
event->delta_discrete, event->source);
}
static void server_cursor_frame(struct wl_listener *listener, void *data) {
/* This event is forwarded by the cursor when a pointer emits an frame
* event. Frame events are sent after regular pointer events to group
* multiple events together. For instance, two axis events may happen at the
* same time, in which case a frame event won't be sent in between. */
struct tinywl_server *server =
wl_container_of(listener, server, cursor_frame);
/* Notify the client with pointer focus of the frame event. */
wlr_seat_pointer_notify_frame(server->seat);
}
static void output_frame(struct wl_listener *listener, void *data) {
/* This function is called every time an output is ready to display a frame,
* generally at the output's refresh rate (e.g. 60Hz). */
struct tinywl_output *output = wl_container_of(listener, output, frame);
struct wlr_scene *scene = output->server->scene;
struct wlr_scene_output *scene_output = wlr_scene_get_scene_output(
scene, output->wlr_output);
/* Render the scene if needed and commit the output */
wlr_scene_output_commit(scene_output);
struct timespec now;
clock_gettime(CLOCK_MONOTONIC, &now);
wlr_scene_output_send_frame_done(scene_output, &now);
}
static void output_request_state(struct wl_listener *listener, void *data) {
/* This function is called when the backend requests a new state for
* the output. For example, Wayland and X11 backends request a new mode
* when the output window is resized. */
struct tinywl_output *output = wl_container_of(listener, output, request_state);
const struct wlr_output_event_request_state *event = data;
wlr_output_commit_state(output->wlr_output, event->state);
}
static void output_destroy(struct wl_listener *listener, void *data) {
struct tinywl_output *output = wl_container_of(listener, output, destroy);
wl_list_remove(&output->frame.link);
wl_list_remove(&output->request_state.link);
wl_list_remove(&output->destroy.link);
wl_list_remove(&output->link);
free(output);
}
static void server_new_output(struct wl_listener *listener, void *data) {
/* This event is raised by the backend when a new output (aka a display or
* monitor) becomes available. */
struct tinywl_server *server =
wl_container_of(listener, server, new_output);
struct wlr_output *wlr_output = data;
/* Configures the output created by the backend to use our allocator
* and our renderer. Must be done once, before commiting the output */
wlr_output_init_render(wlr_output, server->allocator, server->renderer);
/* Some backends don't have modes. DRM+KMS does, and we need to set a mode
* before we can use the output. The mode is a tuple of (width, height,
* refresh rate), and each monitor supports only a specific set of modes. We
* just pick the monitor's preferred mode, a more sophisticated compositor
* would let the user configure it. */
if (!wl_list_empty(&wlr_output->modes)) {
struct wlr_output_mode *mode = wlr_output_preferred_mode(wlr_output);
wlr_output_set_mode(wlr_output, mode);
wlr_output_enable(wlr_output, true);
if (!wlr_output_commit(wlr_output)) {
return;
}
}
/* Allocates and configures our state for this output */
struct tinywl_output *output =
calloc(1, sizeof(struct tinywl_output));
output->wlr_output = wlr_output;
output->server = server;
/* Sets up a listener for the frame event. */
output->frame.notify = output_frame;
wl_signal_add(&wlr_output->events.frame, &output->frame);
/* Sets up a listener for the state request event. */
output->request_state.notify = output_request_state;
wl_signal_add(&wlr_output->events.request_state, &output->request_state);
/* Sets up a listener for the destroy event. */
output->destroy.notify = output_destroy;
wl_signal_add(&wlr_output->events.destroy, &output->destroy);
wl_list_insert(&server->outputs, &output->link);
/* Adds this to the output layout. The add_auto function arranges outputs
* from left-to-right in the order they appear. A more sophisticated
* compositor would let the user configure the arrangement of outputs in the
* layout.
*
* The output layout utility automatically adds a wl_output global to the
* display, which Wayland clients can see to find out information about the
* output (such as DPI, scale factor, manufacturer, etc).
*/
wlr_output_layout_add_auto(server->output_layout, wlr_output);
}
static void xdg_toplevel_map(struct wl_listener *listener, void *data) {
/* Called when the surface is mapped, or ready to display on-screen. */
struct tinywl_view *view = wl_container_of(listener, view, map);
wl_list_insert(&view->server->views, &view->link);
focus_view(view, view->xdg_toplevel->base->surface);
}
static void xdg_toplevel_unmap(struct wl_listener *listener, void *data) {
/* Called when the surface is unmapped, and should no longer be shown. */
struct tinywl_view *view = wl_container_of(listener, view, unmap);
/* Reset the cursor mode if the grabbed view was unmapped. */
if (view == view->server->grabbed_view) {
reset_cursor_mode(view->server);
}
wl_list_remove(&view->link);
}
static void xdg_toplevel_destroy(struct wl_listener *listener, void *data) {
/* Called when the surface is destroyed and should never be shown again. */
struct tinywl_view *view = wl_container_of(listener, view, destroy);
wl_list_remove(&view->map.link);
wl_list_remove(&view->unmap.link);
wl_list_remove(&view->destroy.link);
wl_list_remove(&view->request_move.link);
wl_list_remove(&view->request_resize.link);
wl_list_remove(&view->request_maximize.link);
wl_list_remove(&view->request_fullscreen.link);
free(view);
}
static void begin_interactive(struct tinywl_view *view,
enum tinywl_cursor_mode mode, uint32_t edges) {
/* This function sets up an interactive move or resize operation, where the
* compositor stops propegating pointer events to clients and instead
* consumes them itself, to move or resize windows. */
struct tinywl_server *server = view->server;
struct wlr_surface *focused_surface =
server->seat->pointer_state.focused_surface;
if (view->xdg_toplevel->base->surface !=
wlr_surface_get_root_surface(focused_surface)) {
/* Deny move/resize requests from unfocused clients. */
return;
}
server->grabbed_view = view;
server->cursor_mode = mode;
if (mode == TINYWL_CURSOR_MOVE) {
server->grab_x = server->cursor->x - view->scene_tree->node.x;
server->grab_y = server->cursor->y - view->scene_tree->node.y;
} else {
struct wlr_box geo_box;
wlr_xdg_surface_get_geometry(view->xdg_toplevel->base, &geo_box);
double border_x = (view->scene_tree->node.x + geo_box.x) +
((edges & WLR_EDGE_RIGHT) ? geo_box.width : 0);
double border_y = (view->scene_tree->node.y + geo_box.y) +
((edges & WLR_EDGE_BOTTOM) ? geo_box.height : 0);
server->grab_x = server->cursor->x - border_x;
server->grab_y = server->cursor->y - border_y;
server->grab_geobox = geo_box;
server->grab_geobox.x += view->scene_tree->node.x;
server->grab_geobox.y += view->scene_tree->node.y;
server->resize_edges = edges;
}
}
static void xdg_toplevel_request_move(
struct wl_listener *listener, void *data) {
/* This event is raised when a client would like to begin an interactive
* move, typically because the user clicked on their client-side
* decorations. Note that a more sophisticated compositor should check the
* provided serial against a list of button press serials sent to this
* client, to prevent the client from requesting this whenever they want. */
struct tinywl_view *view = wl_container_of(listener, view, request_move);
begin_interactive(view, TINYWL_CURSOR_MOVE, 0);
}
static void xdg_toplevel_request_resize(
struct wl_listener *listener, void *data) {
/* This event is raised when a client would like to begin an interactive
* resize, typically because the user clicked on their client-side
* decorations. Note that a more sophisticated compositor should check the
* provided serial against a list of button press serials sent to this
* client, to prevent the client from requesting this whenever they want. */
struct wlr_xdg_toplevel_resize_event *event = data;
struct tinywl_view *view = wl_container_of(listener, view, request_resize);
begin_interactive(view, TINYWL_CURSOR_RESIZE, event->edges);
}
static void xdg_toplevel_request_maximize(
struct wl_listener *listener, void *data) {
/* This event is raised when a client would like to maximize itself,
* typically because the user clicked on the maximize button on
* client-side decorations. tinywl doesn't support maximization, but
* to conform to xdg-shell protocol we still must send a configure.
* wlr_xdg_surface_schedule_configure() is used to send an empty reply. */
struct tinywl_view *view =
wl_container_of(listener, view, request_maximize);
wlr_xdg_surface_schedule_configure(view->xdg_toplevel->base);
}
static void xdg_toplevel_request_fullscreen(
struct wl_listener *listener, void *data) {
/* Just as with request_maximize, we must send a configure here. */
struct tinywl_view *view =
wl_container_of(listener, view, request_fullscreen);
wlr_xdg_surface_schedule_configure(view->xdg_toplevel->base);
}
static void server_new_xdg_surface(struct wl_listener *listener, void *data) {
/* This event is raised when wlr_xdg_shell receives a new xdg surface from a
* client, either a toplevel (application window) or popup. */
struct tinywl_server *server =
wl_container_of(listener, server, new_xdg_surface);
struct wlr_xdg_surface *xdg_surface = data;
/* We must add xdg popups to the scene graph so they get rendered. The
* wlroots scene graph provides a helper for this, but to use it we must
* provide the proper parent scene node of the xdg popup. To enable this,
* we always set the user data field of xdg_surfaces to the corresponding
* scene node. */
if (xdg_surface->role == WLR_XDG_SURFACE_ROLE_POPUP) {
struct wlr_xdg_surface *parent =
wlr_xdg_surface_try_from_wlr_surface(xdg_surface->popup->parent);
assert(parent != NULL);
struct wlr_scene_tree *parent_tree = parent->data;
xdg_surface->data = wlr_scene_xdg_surface_create(
parent_tree, xdg_surface);
return;
}
assert(xdg_surface->role == WLR_XDG_SURFACE_ROLE_TOPLEVEL);
/* Allocate a tinywl_view for this surface */
struct tinywl_view *view =
calloc(1, sizeof(struct tinywl_view));
view->server = server;
view->xdg_toplevel = xdg_surface->toplevel;
view->scene_tree = wlr_scene_xdg_surface_create(
&view->server->scene->tree, view->xdg_toplevel->base);
view->scene_tree->node.data = view;
xdg_surface->data = view->scene_tree;
/* Listen to the various events it can emit */
view->map.notify = xdg_toplevel_map;
wl_signal_add(&xdg_surface->events.map, &view->map);
view->unmap.notify = xdg_toplevel_unmap;
wl_signal_add(&xdg_surface->events.unmap, &view->unmap);
view->destroy.notify = xdg_toplevel_destroy;
wl_signal_add(&xdg_surface->events.destroy, &view->destroy);
/* cotd */
struct wlr_xdg_toplevel *toplevel = xdg_surface->toplevel;
view->request_move.notify = xdg_toplevel_request_move;
wl_signal_add(&toplevel->events.request_move, &view->request_move);
view->request_resize.notify = xdg_toplevel_request_resize;
wl_signal_add(&toplevel->events.request_resize, &view->request_resize);
view->request_maximize.notify = xdg_toplevel_request_maximize;
wl_signal_add(&toplevel->events.request_maximize,
&view->request_maximize);
view->request_fullscreen.notify = xdg_toplevel_request_fullscreen;
wl_signal_add(&toplevel->events.request_fullscreen,
&view->request_fullscreen);
}
int main(int argc, char *argv[]) {
wlr_log_init(WLR_DEBUG, NULL);
char *startup_cmd = NULL;
int c;
while ((c = getopt(argc, argv, "s:h")) != -1) {
switch (c) {
case 's':
startup_cmd = optarg;
break;
default:
printf("Usage: %s [-s startup command]\n", argv[0]);
return 0;
}
}
if (optind < argc) {
printf("Usage: %s [-s startup command]\n", argv[0]);
return 0;
}
struct tinywl_server server;
/* The Wayland display is managed by libwayland. It handles accepting
* clients from the Unix socket, manging Wayland globals, and so on. */
server.wl_display = wl_display_create();
/* The backend is a wlroots feature which abstracts the underlying input and
* output hardware. The autocreate option will choose the most suitable
* backend based on the current environment, such as opening an X11 window
* if an X11 server is running. */
server.backend = wlr_backend_autocreate(server.wl_display, NULL);
if (server.backend == NULL) {
wlr_log(WLR_ERROR, "failed to create wlr_backend");
return 1;
}
/* Autocreates a renderer, either Pixman, GLES2 or Vulkan for us. The user
* can also specify a renderer using the WLR_RENDERER env var.
* The renderer is responsible for defining the various pixel formats it
* supports for shared memory, this configures that for clients. */
server.renderer = wlr_renderer_autocreate(server.backend);
if (server.renderer == NULL) {
wlr_log(WLR_ERROR, "failed to create wlr_renderer");
return 1;
}
wlr_renderer_init_wl_display(server.renderer, server.wl_display);
/* Autocreates an allocator for us.
* The allocator is the bridge between the renderer and the backend. It
* handles the buffer creation, allowing wlroots to render onto the
* screen */
server.allocator = wlr_allocator_autocreate(server.backend,
server.renderer);
if (server.allocator == NULL) {
wlr_log(WLR_ERROR, "failed to create wlr_allocator");
return 1;
}
/* This creates some hands-off wlroots interfaces. The compositor is
* necessary for clients to allocate surfaces, the subcompositor allows to
* assign the role of subsurfaces to surfaces and the data device manager
* handles the clipboard. Each of these wlroots interfaces has room for you
* to dig your fingers in and play with their behavior if you want. Note that
* the clients cannot set the selection directly without compositor approval,
* see the handling of the request_set_selection event below.*/
wlr_compositor_create(server.wl_display, server.renderer);
wlr_subcompositor_create(server.wl_display);
wlr_data_device_manager_create(server.wl_display);
/* Creates an output layout, which a wlroots utility for working with an
* arrangement of screens in a physical layout. */
server.output_layout = wlr_output_layout_create();
/* Configure a listener to be notified when new outputs are available on the
* backend. */
wl_list_init(&server.outputs);
server.new_output.notify = server_new_output;
wl_signal_add(&server.backend->events.new_output, &server.new_output);
/* Create a scene graph. This is a wlroots abstraction that handles all
* rendering and damage tracking. All the compositor author needs to do
* is add things that should be rendered to the scene graph at the proper
* positions and then call wlr_scene_output_commit() to render a frame if
* necessary.
*/
server.scene = wlr_scene_create();
wlr_scene_attach_output_layout(server.scene, server.output_layout);
/* Set up xdg-shell version 3. The xdg-shell is a Wayland protocol which is
* used for application windows. For more detail on shells, refer to my
* article:
*
* https://drewdevault.com/2018/07/29/Wayland-shells.html
*/
wl_list_init(&server.views);
server.xdg_shell = wlr_xdg_shell_create(server.wl_display, 3);
server.new_xdg_surface.notify = server_new_xdg_surface;
wl_signal_add(&server.xdg_shell->events.new_surface,
&server.new_xdg_surface);
/*
* Creates a cursor, which is a wlroots utility for tracking the cursor
* image shown on screen.
*/
server.cursor = wlr_cursor_create();
wlr_cursor_attach_output_layout(server.cursor, server.output_layout);
/* Creates an xcursor manager, another wlroots utility which loads up
* Xcursor themes to source cursor images from and makes sure that cursor
* images are available at all scale factors on the screen (necessary for
* HiDPI support). We add a cursor theme at scale factor 1 to begin with. */
server.cursor_mgr = wlr_xcursor_manager_create(NULL, 24);
wlr_xcursor_manager_load(server.cursor_mgr, 1);
/*
* wlr_cursor *only* displays an image on screen. It does not move around
* when the pointer moves. However, we can attach input devices to it, and
* it will generate aggregate events for all of them. In these events, we
* can choose how we want to process them, forwarding them to clients and
* moving the cursor around. More detail on this process is described in my
* input handling blog post:
*
* https://drewdevault.com/2018/07/17/Input-handling-in-wlroots.html
*
* And more comments are sprinkled throughout the notify functions above.
*/
server.cursor_mode = TINYWL_CURSOR_PASSTHROUGH;
server.cursor_motion.notify = server_cursor_motion;
wl_signal_add(&server.cursor->events.motion, &server.cursor_motion);
server.cursor_motion_absolute.notify = server_cursor_motion_absolute;
wl_signal_add(&server.cursor->events.motion_absolute,
&server.cursor_motion_absolute);
server.cursor_button.notify = server_cursor_button;
wl_signal_add(&server.cursor->events.button, &server.cursor_button);
server.cursor_axis.notify = server_cursor_axis;
wl_signal_add(&server.cursor->events.axis, &server.cursor_axis);
server.cursor_frame.notify = server_cursor_frame;
wl_signal_add(&server.cursor->events.frame, &server.cursor_frame);
/*
* Configures a seat, which is a single "seat" at which a user sits and
* operates the computer. This conceptually includes up to one keyboard,
* pointer, touch, and drawing tablet device. We also rig up a listener to
* let us know when new input devices are available on the backend.
*/
wl_list_init(&server.keyboards);
server.new_input.notify = server_new_input;
wl_signal_add(&server.backend->events.new_input, &server.new_input);
server.seat = wlr_seat_create(server.wl_display, "seat0");
server.request_cursor.notify = seat_request_cursor;
wl_signal_add(&server.seat->events.request_set_cursor,
&server.request_cursor);
server.request_set_selection.notify = seat_request_set_selection;
wl_signal_add(&server.seat->events.request_set_selection,
&server.request_set_selection);
/* Add a Unix socket to the Wayland display. */
const char *socket = wl_display_add_socket_auto(server.wl_display);
if (!socket) {
wlr_backend_destroy(server.backend);
return 1;
}
/* Start the backend. This will enumerate outputs and inputs, become the DRM
* master, etc */
if (!wlr_backend_start(server.backend)) {
wlr_backend_destroy(server.backend);
wl_display_destroy(server.wl_display);
return 1;
}
/* Set the WAYLAND_DISPLAY environment variable to our socket and run the
* startup command if requested. */
setenv("WAYLAND_DISPLAY", socket, true);
if (startup_cmd) {
if (fork() == 0) {
execl("/bin/sh", "/bin/sh", "-c", startup_cmd, (void *)NULL);
}
}
/* Run the Wayland event loop. This does not return until you exit the
* compositor. Starting the backend rigged up all of the necessary event
* loop configuration to listen to libinput events, DRM events, generate
* frame events at the refresh rate, and so on. */
wlr_log(WLR_INFO, "Running Wayland compositor on WAYLAND_DISPLAY=%s",
socket);
wl_display_run(server.wl_display);
/* Once wl_display_run returns, we shut down the server. */
wl_display_destroy_clients(server.wl_display);
wl_display_destroy(server.wl_display);
return 0;
}