1 files changed, 354 insertions, 0 deletions

diff --git a/sway/lock.c b/sway/lock.c
new file mode 100644
index 00000000..8ad9c3f6
--- /dev/null
+++ b/sway/lock.c
@@ -0,0 +1,354 @@
+#define _POSIX_C_SOURCE 200809L
+#include <assert.h>
+#include <wlr/types/wlr_scene.h>
+#include "log.h"
+#include "sway/input/cursor.h"
+#include "sway/input/keyboard.h"
+#include "sway/input/seat.h"
+#include "sway/layers.h"
+#include "sway/output.h"
+#include "sway/server.h"
+
+struct sway_session_lock_output {
+        struct wlr_scene_tree *tree;
+        struct wlr_scene_rect *background;
+        struct sway_session_lock *lock;
+
+        struct sway_output *output;
+
+        struct wl_list link; // sway_session_lock::outputs
+
+        struct wl_listener destroy;
+        struct wl_listener commit;
+
+        struct wlr_session_lock_surface_v1 *surface;
+
+        // invalid if surface is NULL
+        struct wl_listener surface_destroy;
+        struct wl_listener surface_map;
+};
+
+static void focus_surface(struct sway_session_lock *lock,
+                struct wlr_surface *focused) {
+        lock->focused = focused;
+
+        struct sway_seat *seat;
+        wl_list_for_each(seat, &server.input->seats, link) {
+                seat_set_focus_surface(seat, focused, false);
+        }
+}
+
+static void refocus_output(struct sway_session_lock_output *output) {
+        // Move the seat focus to another surface if one is available
+        if (output->lock->focused == output->surface->surface) {
+                struct wlr_surface *next_focus = NULL;
+
+                struct sway_session_lock_output *candidate;
+                wl_list_for_each(candidate, &output->lock->outputs, link) {
+                        if (candidate == output || !candidate->surface) {
+                                continue;
+                        }
+
+                        if (candidate->surface->surface->mapped) {
+                                next_focus = candidate->surface->surface;
+                                break;
+                        }
+                }
+
+                focus_surface(output->lock, next_focus);
+        }
+}
+
+static void handle_surface_map(struct wl_listener *listener, void *data) {
+        struct sway_session_lock_output *surf = wl_container_of(listener, surf, surface_map);
+        if (surf->lock->focused == NULL) {
+                focus_surface(surf->lock, surf->surface->surface);
+        }
+        cursor_rebase_all();
+}
+
+static void handle_surface_destroy(struct wl_listener *listener, void *data) {
+        struct sway_session_lock_output *output =
+                wl_container_of(listener, output, surface_destroy);
+        refocus_output(output);
+
+        sway_assert(output->surface, "Trying to destroy a surface that the lock doesn't think exists");
+        output->surface = NULL;
+        wl_list_remove(&output->surface_destroy.link);
+        wl_list_remove(&output->surface_map.link);
+}
+
+static void lock_output_reconfigure(struct sway_session_lock_output *output) {
+        int width = output->output->width;
+        int height = output->output->height;
+
+        wlr_scene_rect_set_size(output->background, width, height);
+
+        if (output->surface) {
+                wlr_session_lock_surface_v1_configure(output->surface, width, height);
+        }
+}
+
+static void handle_new_surface(struct wl_listener *listener, void *data) {
+        struct sway_session_lock *lock = wl_container_of(listener, lock, new_surface);
+        struct wlr_session_lock_surface_v1 *lock_surface = data;
+        struct sway_output *output = lock_surface->output->data;
+
+        sway_log(SWAY_DEBUG, "new lock layer surface");
+
+        struct sway_session_lock_output *current_lock_output, *lock_output = NULL;
+        wl_list_for_each(current_lock_output, &lock->outputs, link) {
+                if (current_lock_output->output == output) {
+                        lock_output = current_lock_output;
+                        break;
+                }
+        }
+        sway_assert(lock_output, "Couldn't find output to lock");
+        sway_assert(!lock_output->surface, "Tried to reassign a surface to an existing output");
+
+        lock_output->surface = lock_surface;
+
+        wlr_scene_subsurface_tree_create(lock_output->tree, lock_surface->surface);
+
+        lock_output->surface_destroy.notify = handle_surface_destroy;
+        wl_signal_add(&lock_surface->events.destroy, &lock_output->surface_destroy);
+        lock_output->surface_map.notify = handle_surface_map;
+        wl_signal_add(&lock_surface->surface->events.map, &lock_output->surface_map);
+
+        lock_output_reconfigure(lock_output);
+}
+
+static void sway_session_lock_output_destroy(struct sway_session_lock_output *output) {
+        if (output->surface) {
+                refocus_output(output);
+                wl_list_remove(&output->surface_destroy.link);
+                wl_list_remove(&output->surface_map.link);
+        }
+
+        wl_list_remove(&output->commit.link);
+        wl_list_remove(&output->destroy.link);
+        wl_list_remove(&output->link);
+
+        free(output);
+}
+
+static void lock_node_handle_destroy(struct wl_listener *listener, void *data) {
+        struct sway_session_lock_output *output =
+                wl_container_of(listener, output, destroy);
+        sway_session_lock_output_destroy(output);
+}
+
+static void lock_output_handle_commit(struct wl_listener *listener, void *data) {
+        struct wlr_output_event_commit *event = data;
+        struct sway_session_lock_output *output =
+                wl_container_of(listener, output, commit);
+        if (event->state->committed & (
+                        WLR_OUTPUT_STATE_MODE |
+                        WLR_OUTPUT_STATE_SCALE |
+                        WLR_OUTPUT_STATE_TRANSFORM)) {
+                lock_output_reconfigure(output);
+        }
+}
+
+static struct sway_session_lock_output *session_lock_output_create(
+                struct sway_session_lock *lock, struct sway_output *output) {
+        struct sway_session_lock_output *lock_output = calloc(1, sizeof(*lock_output));
+        if (!lock_output) {
+                sway_log(SWAY_ERROR, "failed to allocate a session lock output");
+                return NULL;
+        }
+
+        struct wlr_scene_tree *tree = wlr_scene_tree_create(output->layers.session_lock);
+        if (!tree) {
+                sway_log(SWAY_ERROR, "failed to allocate a session lock output scene tree");
+                free(lock_output);
+                return NULL;
+        }
+
+        struct wlr_scene_rect *background = wlr_scene_rect_create(tree, 0, 0, (float[4]){
+                lock->abandoned ? 1.f : 0.f,
+                0.f,
+                0.f,
+                1.f,
+        });
+        if (!background) {
+                sway_log(SWAY_ERROR, "failed to allocate a session lock output scene background");
+                wlr_scene_node_destroy(&tree->node);
+                free(lock_output);
+                return NULL;
+        }
+
+        lock_output->output = output;
+        lock_output->tree = tree;
+        lock_output->background = background;
+        lock_output->lock = lock;
+
+        lock_output->destroy.notify = lock_node_handle_destroy;
+        wl_signal_add(&tree->node.events.destroy, &lock_output->destroy);
+
+        lock_output->commit.notify = lock_output_handle_commit;
+        wl_signal_add(&output->wlr_output->events.commit, &lock_output->commit);
+
+        lock_output_reconfigure(lock_output);
+
+        wl_list_insert(&lock->outputs, &lock_output->link);
+
+        return lock_output;
+}
+
+static void sway_session_lock_destroy(struct sway_session_lock* lock) {
+        struct sway_session_lock_output *lock_output, *tmp_lock_output;
+        wl_list_for_each_safe(lock_output, tmp_lock_output, &lock->outputs, link) {
+                // destroying the node will also destroy the whole lock output
+                wlr_scene_node_destroy(&lock_output->tree->node);
+        }
+
+        if (server.session_lock.lock == lock) {
+                server.session_lock.lock = NULL;
+        }
+
+        if (!lock->abandoned) {
+                wl_list_remove(&lock->destroy.link);
+                wl_list_remove(&lock->unlock.link);
+                wl_list_remove(&lock->new_surface.link);
+        }
+
+        free(lock);
+}
+
+static void handle_unlock(struct wl_listener *listener, void *data) {
+        struct sway_session_lock *lock = wl_container_of(listener, lock, unlock);
+        sway_log(SWAY_DEBUG, "session unlocked");
+
+        sway_session_lock_destroy(lock);
+
+        struct sway_seat *seat;
+        wl_list_for_each(seat, &server.input->seats, link) {
+                // copied from seat_set_focus_layer -- deduplicate?
+                struct sway_node *previous = seat_get_focus_inactive(seat, &root->node);
+                if (previous) {
+                        // Hack to get seat to re-focus the return value of get_focus
+                        seat_set_focus(seat, NULL);
+                        seat_set_focus(seat, previous);
+                }
+        }
+
+        // Triggers a refocus of the topmost surface layer if necessary
+        // TODO: Make layer surface focus per-output based on cursor position
+        for (int i = 0; i < root->outputs->length; ++i) {
+                struct sway_output *output = root->outputs->items[i];
+                arrange_layers(output);
+        }
+}
+
+static void handle_abandon(struct wl_listener *listener, void *data) {
+        struct sway_session_lock *lock = wl_container_of(listener, lock, destroy);
+        sway_log(SWAY_INFO, "session lock abandoned");
+
+        struct sway_session_lock_output *lock_output;
+        wl_list_for_each(lock_output, &lock->outputs, link) {
+                wlr_scene_rect_set_color(lock_output->background,
+                        (float[4]){ 1.f, 0.f, 0.f, 1.f });
+        }
+
+        lock->abandoned = true;
+        wl_list_remove(&lock->destroy.link);
+        wl_list_remove(&lock->unlock.link);
+        wl_list_remove(&lock->new_surface.link);
+}
+
+static void handle_session_lock(struct wl_listener *listener, void *data) {
+        struct wlr_session_lock_v1 *lock = data;
+        struct wl_client *client = wl_resource_get_client(lock->resource);
+
+        if (server.session_lock.lock) {
+                if (server.session_lock.lock->abandoned) {
+                        sway_log(SWAY_INFO, "Replacing abandoned lock");
+                        sway_session_lock_destroy(server.session_lock.lock);
+                } else {
+                        sway_log(SWAY_ERROR, "Cannot lock an already locked session");
+                        wlr_session_lock_v1_destroy(lock);
+                        return;
+                }
+        }
+
+        struct sway_session_lock *sway_lock = calloc(1, sizeof(*sway_lock));
+        if (!sway_lock) {
+                sway_log(SWAY_ERROR, "failed to allocate a session lock object");
+                wlr_session_lock_v1_destroy(lock);
+                return;
+        }
+
+        wl_list_init(&sway_lock->outputs);
+
+        sway_log(SWAY_DEBUG, "session locked");
+
+        struct sway_seat *seat;
+        wl_list_for_each(seat, &server.input->seats, link) {
+                seat_unfocus_unless_client(seat, client);
+        }
+
+        struct sway_output *output;
+        wl_list_for_each(output, &root->all_outputs, link) {
+                sway_session_lock_add_output(sway_lock, output);
+        }
+
+        sway_lock->new_surface.notify = handle_new_surface;
+        wl_signal_add(&lock->events.new_surface, &sway_lock->new_surface);
+        sway_lock->unlock.notify = handle_unlock;
+        wl_signal_add(&lock->events.unlock, &sway_lock->unlock);
+        sway_lock->destroy.notify = handle_abandon;
+        wl_signal_add(&lock->events.destroy, &sway_lock->destroy);
+
+        wlr_session_lock_v1_send_locked(lock);
+        server.session_lock.lock = sway_lock;
+}
+
+static void handle_session_lock_destroy(struct wl_listener *listener, void *data) {
+        // if the server shuts down while a lock is active, destroy the lock
+        if (server.session_lock.lock) {
+                sway_session_lock_destroy(server.session_lock.lock);
+        }
+
+        wl_list_remove(&server.session_lock.new_lock.link);
+        wl_list_remove(&server.session_lock.manager_destroy.link);
+
+        server.session_lock.manager = NULL;
+}
+
+void sway_session_lock_add_output(struct sway_session_lock *lock,
+                struct sway_output *output) {
+        struct sway_session_lock_output *lock_output =
+                session_lock_output_create(lock, output);
+
+        // if we run out of memory while trying to lock the screen, the best we
+        // can do is kill the sway process. Security conscious users will have
+        // the sway session fall back to a login shell.
+        if (!lock_output) {
+                sway_log(SWAY_ERROR, "aborting: failed to allocate a lock output");
+                abort();
+        }
+}
+
+bool sway_session_lock_has_surface(struct sway_session_lock *lock,
+                struct wlr_surface *surface) {
+        struct sway_session_lock_output *lock_output;
+        wl_list_for_each(lock_output, &lock->outputs, link) {
+                if (lock_output->surface && lock_output->surface->surface == surface) {
+                        return true;
+                }
+        }
+
+        return false;
+}
+
+void sway_session_lock_init(void) {
+        server.session_lock.manager = wlr_session_lock_manager_v1_create(server.wl_display);
+
+        server.session_lock.new_lock.notify = handle_session_lock;
+        server.session_lock.manager_destroy.notify = handle_session_lock_destroy;
+        wl_signal_add(&server.session_lock.manager->events.new_lock,
+                &server.session_lock.new_lock);
+        wl_signal_add(&server.session_lock.manager->events.destroy,
+                &server.session_lock.manager_destroy);
+}