Merge pull request #2003 from emersion/fix-swaylock-hotplugging

Fix swaylock crashing when plugging/unplugging output

3 files changed, 78 insertions, 39 deletions

diff --git a/include/swaylock/swaylock.h b/include/swaylock/swaylock.h
index e161ada9..dae823b8 100644
--- a/include/swaylock/swaylock.h
+++ b/include/swaylock/swaylock.h
@@ -10,13 +10,13 @@
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 
 enum auth_state {
-    AUTH_STATE_IDLE,
-    AUTH_STATE_CLEAR,
-    AUTH_STATE_INPUT,
-    AUTH_STATE_INPUT_NOP,
-    AUTH_STATE_BACKSPACE,
-    AUTH_STATE_VALIDATING,
-    AUTH_STATE_INVALID,
+        AUTH_STATE_IDLE,
+        AUTH_STATE_CLEAR,
+        AUTH_STATE_INPUT,
+        AUTH_STATE_INPUT_NOP,
+        AUTH_STATE_BACKSPACE,
+        AUTH_STATE_VALIDATING,
+        AUTH_STATE_INVALID,
 };
 
 struct swaylock_args {
@@ -50,6 +50,7 @@ struct swaylock_surface {
         cairo_surface_t *image;
         struct swaylock_state *state;
         struct wl_output *output;
+        uint32_t output_global_name;
         struct zxdg_output_v1 *xdg_output;
         struct wl_surface *surface;
         struct zwlr_layer_surface_v1 *layer_surface;
diff --git a/swaylock/main.c b/swaylock/main.c
index 11b5e8c8..f89f2849 100644
--- a/swaylock/main.c
+++ b/swaylock/main.c
@@ -64,6 +64,52 @@ static void daemonize() {
         }
 }
 
+static void destroy_surface(struct swaylock_surface *surface) {
+        wl_list_remove(&surface->link);
+        if (surface->layer_surface != NULL) {
+                zwlr_layer_surface_v1_destroy(surface->layer_surface);
+        }
+        if (surface->surface != NULL) {
+                wl_surface_destroy(surface->surface);
+        }
+        destroy_buffer(&surface->buffers[0]);
+        destroy_buffer(&surface->buffers[1]);
+        wl_output_destroy(surface->output);
+        free(surface);
+}
+
+static const struct zwlr_layer_surface_v1_listener layer_surface_listener;
+
+static cairo_surface_t *select_image(struct swaylock_state *state,
+                struct swaylock_surface *surface);
+
+static void create_layer_surface(struct swaylock_surface *surface) {
+        struct swaylock_state *state = surface->state;
+
+        surface->image = select_image(state, surface);
+
+        surface->surface = wl_compositor_create_surface(state->compositor);
+        assert(surface->surface);
+
+        surface->layer_surface = zwlr_layer_shell_v1_get_layer_surface(
+                        state->layer_shell, surface->surface, surface->output,
+                        ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY, "lockscreen");
+        assert(surface->layer_surface);
+
+        zwlr_layer_surface_v1_set_size(surface->layer_surface, 0, 0);
+        zwlr_layer_surface_v1_set_anchor(surface->layer_surface,
+                        ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP |
+                        ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
+                        ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM |
+                        ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT);
+        zwlr_layer_surface_v1_set_exclusive_zone(surface->layer_surface, -1);
+        zwlr_layer_surface_v1_set_keyboard_interactivity(
+                        surface->layer_surface, true);
+        zwlr_layer_surface_v1_add_listener(surface->layer_surface,
+                        &layer_surface_listener, surface);
+        wl_surface_commit(surface->surface);
+}
+
 static void layer_surface_configure(void *data,
                 struct zwlr_layer_surface_v1 *layer_surface,
                 uint32_t serial, uint32_t width, uint32_t height) {
@@ -77,9 +123,7 @@ static void layer_surface_configure(void *data,
 static void layer_surface_closed(void *data,
                 struct zwlr_layer_surface_v1 *layer_surface) {
         struct swaylock_surface *surface = data;
-        zwlr_layer_surface_v1_destroy(surface->layer_surface);
-        wl_surface_destroy(surface->surface);
-        surface->state->run_display = false;
+        destroy_surface(surface);
 }
 
 static const struct zwlr_layer_surface_v1_listener layer_surface_listener = {
@@ -181,14 +225,27 @@ static void handle_global(void *data, struct wl_registry *registry,
                 surface->state = state;
                 surface->output = wl_registry_bind(registry, name,
                                 &wl_output_interface, 3);
+                surface->output_global_name = name;
                 wl_output_add_listener(surface->output, &_wl_output_listener, surface);
                 wl_list_insert(&state->surfaces, &surface->link);
+
+                if (state->run_display) {
+                        create_layer_surface(surface);
+                        wl_display_roundtrip(state->display);
+                }
         }
 }
 
 static void handle_global_remove(void *data, struct wl_registry *registry,
                 uint32_t name) {
-        // who cares
+        struct swaylock_state *state = data;
+        struct swaylock_surface *surface;
+        wl_list_for_each(surface, &state->surfaces, link) {
+                if (surface->output_global_name == name) {
+                        destroy_surface(surface);
+                        break;
+                }
+        }
 }
 
 static const struct wl_registry_listener registry_listener = {
@@ -276,7 +333,7 @@ int main(int argc, char **argv) {
                 {0, 0, 0, 0}
         };
 
-        const char *usage =
+        const char usage[] =
                 "Usage: swaylock [options...]\n"
                 "\n"
                 "  -h, --help                     Show help message and quit.\n"
@@ -288,13 +345,13 @@ int main(int argc, char **argv) {
                 "  -u, --no-unlock-indicator      Disable the unlock indicator.\n"
                 "  -f, --daemonize                Detach from the controlling terminal.\n";
 
-        struct swaylock_args args = {
+        state.args = (struct swaylock_args){
                 .mode = BACKGROUND_MODE_SOLID_COLOR,
                 .color = 0xFFFFFFFF,
                 .show_indicator = true,
         };
-        state.args = args;
         wl_list_init(&state.images);
+
         wlr_log_init(L_DEBUG, NULL);
 
         int c;
@@ -369,6 +426,8 @@ int main(int argc, char **argv) {
                 return 0;
         }
 
+        zwlr_input_inhibit_manager_v1_get_inhibitor(state.input_inhibit_manager);
+
         if (state.zxdg_output_manager) {
                 struct swaylock_surface *surface;
                 wl_list_for_each(surface, &state.surfaces, link) {
@@ -385,33 +444,9 @@ int main(int argc, char **argv) {
 
         struct swaylock_surface *surface;
         wl_list_for_each(surface, &state.surfaces, link) {
-                surface->image = select_image(&state, surface);
-
-                surface->surface = wl_compositor_create_surface(state.compositor);
-                assert(surface->surface);
-
-                surface->layer_surface = zwlr_layer_shell_v1_get_layer_surface(
-                                state.layer_shell, surface->surface, surface->output,
-                                ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY, "lockscreen");
-                assert(surface->layer_surface);
-
-                zwlr_layer_surface_v1_set_size(surface->layer_surface, 0, 0);
-                zwlr_layer_surface_v1_set_anchor(surface->layer_surface,
-                                ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP |
-                                ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
-                                ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM |
-                                ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT);
-                zwlr_layer_surface_v1_set_exclusive_zone(surface->layer_surface, -1);
-                zwlr_layer_surface_v1_set_keyboard_interactivity(
-                                surface->layer_surface, true);
-                zwlr_layer_surface_v1_add_listener(surface->layer_surface,
-                                &layer_surface_listener, surface);
-                wl_surface_commit(surface->surface);
-                wl_display_roundtrip(state.display);
+                create_layer_surface(surface);
         }
 
-        zwlr_input_inhibit_manager_v1_get_inhibitor(state.input_inhibit_manager);
-
         state.run_display = true;
         while (wl_display_dispatch(state.display) != -1 && state.run_display) {
                 // This space intentionally left blank
diff --git a/swaylock/render.c b/swaylock/render.c
index cc40f4e9..05236dea 100644
--- a/swaylock/render.c
+++ b/swaylock/render.c
@@ -17,6 +17,9 @@ void render_frame(struct swaylock_surface *surface) {
 
         int buffer_width = surface->width * surface->scale;
         int buffer_height = surface->height * surface->scale;
+        if (buffer_width == 0 || buffer_height == 0) {
+                return; // not yet configured
+        }
 
         surface->current_buffer = get_next_buffer(state->shm,
                         surface->buffers, buffer_width, buffer_height);