swaybar: handle hotplugging

Don't kill and respawn swaybars on hotplug.

1 files changed, 70 insertions, 41 deletions

diff --git a/swaybar/bar.c b/swaybar/bar.c
index 3ae730f7..49a8ece1 100644
--- a/swaybar/bar.c
+++ b/swaybar/bar.c
@@ -48,8 +48,13 @@ static void swaybar_output_free(struct swaybar_output *output) {
                 return;
         }
         wlr_log(WLR_DEBUG, "Removing output %s", output->name);
-        zwlr_layer_surface_v1_destroy(output->layer_surface);
-        wl_surface_destroy(output->surface);
+        if (output->layer_surface != NULL) {
+                zwlr_layer_surface_v1_destroy(output->layer_surface);
+        }
+        if (output->surface != NULL) {
+                wl_surface_destroy(output->surface);
+        }
+        zxdg_output_v1_destroy(output->xdg_output);
         wl_output_destroy(output->output);
         destroy_buffer(&output->buffers[0]);
         destroy_buffer(&output->buffers[1]);
@@ -283,6 +288,37 @@ const struct wl_seat_listener seat_listener = {
         .name = seat_handle_name,
 };
 
+static void add_layer_surface(struct swaybar_output *output) {
+        if (output->surface != NULL) {
+                return;
+        }
+        struct swaybar *bar = output->bar;
+
+        output->surface = wl_compositor_create_surface(bar->compositor);
+        assert(output->surface);
+        output->layer_surface = zwlr_layer_shell_v1_get_layer_surface(
+                        bar->layer_shell, output->surface, output->output,
+                        ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM, "panel");
+        assert(output->layer_surface);
+        zwlr_layer_surface_v1_add_listener(output->layer_surface,
+                        &layer_surface_listener, output);
+        zwlr_layer_surface_v1_set_anchor(output->layer_surface,
+                        bar->config->position);
+}
+
+static bool bar_uses_output(struct swaybar *bar, const char *name) {
+        if (bar->config->all_outputs) {
+                return true;
+        }
+        struct config_output *coutput;
+        wl_list_for_each(coutput, &bar->config->outputs, link) {
+                if (strcmp(coutput->name, name) == 0) {
+                        return true;
+                }
+        }
+        return false;
+}
+
 static void output_geometry(void *data, struct wl_output *output, int32_t x,
                 int32_t y, int32_t width_mm, int32_t height_mm, int32_t subpixel,
                 const char *make, const char *model, int32_t transform) {
@@ -326,7 +362,22 @@ static void xdg_output_handle_logical_size(void *data,
 
 static void xdg_output_handle_done(void *data,
                 struct zxdg_output_v1 *xdg_output) {
-        // Who cares
+        struct swaybar_output *output = data;
+        struct swaybar *bar = output->bar;
+
+        assert(output->name != NULL);
+        if (!bar_uses_output(bar, output->name)) {
+                swaybar_output_free(output);
+                return;
+        }
+
+        if (wl_list_empty(&output->link)) {
+                wl_list_remove(&output->link);
+                wl_list_insert(&bar->outputs, &output->link);
+
+                add_layer_surface(output);
+                render_frame(bar, output);
+        }
 }
 
 static void xdg_output_handle_name(void *data,
@@ -349,17 +400,15 @@ struct zxdg_output_v1_listener xdg_output_listener = {
         .description = xdg_output_handle_description,
 };
 
-static bool bar_uses_output(struct swaybar *bar, const char *name) {
-        if (bar->config->all_outputs) {
-                return true;
-        }
-        struct config_output *coutput;
-        wl_list_for_each(coutput, &bar->config->outputs, link) {
-                if (strcmp(coutput->name, name) == 0) {
-                        return true;
-                }
+static void add_xdg_output(struct swaybar_output *output) {
+        if (output->xdg_output != NULL) {
+                return;
         }
-        return false;
+        assert(output->bar->xdg_output_manager != NULL);
+        output->xdg_output = zxdg_output_manager_v1_get_xdg_output(
+                output->bar->xdg_output_manager, output->output);
+        zxdg_output_v1_add_listener(output->xdg_output, &xdg_output_listener,
+                output);
 }
 
 static void handle_global(void *data, struct wl_registry *registry,
@@ -386,7 +435,10 @@ static void handle_global(void *data, struct wl_registry *registry,
                 output->wl_name = name;
                 wl_list_init(&output->workspaces);
                 wl_list_init(&output->hotspots);
-                wl_list_insert(&bar->outputs, &output->link);
+                wl_list_init(&output->link);
+                if (bar->xdg_output_manager != NULL) {
+                        add_xdg_output(output);
+                }
         } else if (strcmp(interface, zwlr_layer_shell_v1_interface.name) == 0) {
                 bar->layer_shell = wl_registry_bind(
                                 registry, name, &zwlr_layer_shell_v1_interface, 1);
@@ -416,7 +468,9 @@ static const struct wl_registry_listener registry_listener = {
 static void render_all_frames(struct swaybar *bar) {
         struct swaybar_output *output;
         wl_list_for_each(output, &bar->outputs, link) {
-                render_frame(bar, output);
+                if (output->surface != NULL) {
+                        render_frame(bar, output);
+                }
         }
 }
 
@@ -443,23 +497,10 @@ void bar_setup(struct swaybar *bar,
 
         struct swaybar_output *output;
         wl_list_for_each(output, &bar->outputs, link) {
-                output->xdg_output = zxdg_output_manager_v1_get_xdg_output(
-                        bar->xdg_output_manager, output->output);
-                zxdg_output_v1_add_listener(output->xdg_output, &xdg_output_listener,
-                        output);
+                add_xdg_output(output);
         }
         wl_display_roundtrip(bar->display);
 
-        struct swaybar_output *output_tmp;
-        wl_list_for_each_safe(output, output_tmp, &bar->outputs, link) {
-                if (!bar_uses_output(bar, output->name)) {
-                        zxdg_output_v1_destroy(output->xdg_output);
-                        wl_output_destroy(output->output);
-                        wl_list_remove(&output->link);
-                        free(output);
-                }
-        }
-
         struct swaybar_pointer *pointer = &bar->pointer;
 
         int max_scale = 1;
@@ -479,18 +520,6 @@ void bar_setup(struct swaybar *bar,
         pointer->cursor_surface = wl_compositor_create_surface(bar->compositor);
         assert(pointer->cursor_surface);
 
-        wl_list_for_each(output, &bar->outputs, link) {
-                output->surface = wl_compositor_create_surface(bar->compositor);
-                assert(output->surface);
-                output->layer_surface = zwlr_layer_shell_v1_get_layer_surface(
-                                bar->layer_shell, output->surface, output->output,
-                                ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM, "panel");
-                assert(output->layer_surface);
-                zwlr_layer_surface_v1_add_listener(output->layer_surface,
-                                &layer_surface_listener, output);
-                zwlr_layer_surface_v1_set_anchor(output->layer_surface,
-                                bar->config->position);
-        }
         ipc_get_workspaces(bar);
         render_all_frames(bar);
 }