config: improvements to the reload validation

For the validation pass of reloading, there is no need to touch swaybg,
swaynag, inputs, outputs, or seats. This drastically improves the speed
of a reload by skipping over the expensive I/O configuration and
handling of wayland clients. As long as the syntax is valid, the
CMD_FAILURE's can be relayed during the actual reload.

3 files changed, 37 insertions, 27 deletions

diff --git a/sway/commands/input.c b/sway/commands/input.c
index a11ad79a..53db9a16 100644
--- a/sway/commands/input.c
+++ b/sway/commands/input.c
@@ -44,23 +44,6 @@ static struct cmd_handler input_config_handlers[] = {
         { "xkb_numlock", input_cmd_xkb_numlock },
 };
 
-/**
- * Re-translate keysyms if a change in the input config could affect them.
- */
-static void retranslate_keysyms(struct input_config *input_config) {
-        for (int i = 0; i < config->input_configs->length; ++i) {
-                struct input_config *ic = config->input_configs->items[i];
-                if (ic->xkb_layout || ic->xkb_file) {
-                        // this is the first config with xkb_layout or xkb_file
-                        if (ic->identifier == input_config->identifier) {
-                                translate_keysyms(ic);
-                        }
-
-                        return;
-                }
-        }
-}
-
 struct cmd_results *cmd_input(int argc, char **argv) {
         struct cmd_results *error = NULL;
         if ((error = checkarg(argc, "input", EXPECTED_AT_LEAST, 2))) {
@@ -106,8 +89,9 @@ struct cmd_results *cmd_input(int argc, char **argv) {
                         return res;
                 }
 
-                input_manager_apply_input_config(ic);
-                retranslate_keysyms(ic);
+                if (!config->reloading) {
+                        input_manager_apply_input_config(ic);
+                }
         } else {
                 free_input_config(config->handler_context.input_config);
         }
diff --git a/sway/config.c b/sway/config.c
index 1f03610a..553cba2b 100644
--- a/sway/config.c
+++ b/sway/config.c
@@ -447,15 +447,17 @@ bool load_main_config(const char *file, bool is_active, bool validating) {
                                 old_config->xwayland ? "enabled" : "disabled");
                 config->xwayland = old_config->xwayland;
 
-                if (old_config->swaybg_client != NULL) {
-                        wl_client_destroy(old_config->swaybg_client);
-                }
+                if (!config->validating) {
+                        if (old_config->swaybg_client != NULL) {
+                                wl_client_destroy(old_config->swaybg_client);
+                        }
 
-                if (old_config->swaynag_config_errors.client != NULL) {
-                        wl_client_destroy(old_config->swaynag_config_errors.client);
-                }
+                        if (old_config->swaynag_config_errors.client != NULL) {
+                                wl_client_destroy(old_config->swaynag_config_errors.client);
+                        }
 
-                input_manager_reset_all_inputs();
+                        input_manager_reset_all_inputs();
+                }
         }
 
         config->current_config_path = path;
@@ -520,8 +522,13 @@ bool load_main_config(const char *file, bool is_active, bool validating) {
                 return success;
         }
 
-        if (is_active) {
+        if (is_active && !validating) {
                 input_manager_verify_fallback_seat();
+
+                for (int i = 0; i < config->input_configs->length; i++) {
+                        input_manager_apply_input_config(config->input_configs->items[i]);
+                }
+
                 for (int i = 0; i < config->seat_configs->length; i++) {
                         input_manager_apply_seat_config(config->seat_configs->items[i]);
                 }
diff --git a/sway/input/input-manager.c b/sway/input/input-manager.c
index cfd39bab..3d7f9e8b 100644
--- a/sway/input/input-manager.c
+++ b/sway/input/input-manager.c
@@ -359,6 +359,23 @@ void input_manager_set_focus(struct sway_node *node) {
         }
 }
 
+/**
+ * Re-translate keysyms if a change in the input config could affect them.
+ */
+static void retranslate_keysyms(struct input_config *input_config) {
+        for (int i = 0; i < config->input_configs->length; ++i) {
+                struct input_config *ic = config->input_configs->items[i];
+                if (ic->xkb_layout || ic->xkb_file) {
+                        // this is the first config with xkb_layout or xkb_file
+                        if (ic->identifier == input_config->identifier) {
+                                translate_keysyms(ic);
+                        }
+
+                        return;
+                }
+        }
+}
+
 void input_manager_apply_input_config(struct input_config *input_config) {
         struct sway_input_device *input_device = NULL;
         bool wildcard = strcmp(input_config->identifier, "*") == 0;
@@ -376,6 +393,8 @@ void input_manager_apply_input_config(struct input_config *input_config) {
                         }
                 }
         }
+
+        retranslate_keysyms(input_config);
 }
 
 void input_manager_reset_input(struct sway_input_device *input_device) {