config: Batch input/output configuration on load

We batch modesets and input configuration performed during config reload
but commit for every command during the intial config load. There is no
need to perform commits during the initial config load as outputs have
not yet been created, but swaybg spawn should still be batched.

At the same time, replace direct calls to apply output configuration
with request_modeset to properly handle the modeset timer.

sway/commands/input.c

@@ -94,7 +94,7 @@ struct cmd_results *cmd_input(int argc, char **argv) {
 			return res;
 		}
 
-		if (!config->reloading) {
+		if (!config->reading) {
 			input_manager_apply_input_config(ic);
 		}
 	} else {

sway/commands/output.c

@@ -107,17 +107,16 @@ struct cmd_results *cmd_output(int argc, char **argv) {
 
 	store_output_config(output);
 
-	// If reloading, the output configs will be applied after reading the
-	// entire config and before the deferred commands so that an auto generated
-	// workspace name is not given to re-enabled outputs.
-	if (!config->reloading && !config->validating) {
-		apply_stored_output_configs();
-		if (background) {
-			if (!spawn_swaybg()) {
-				return cmd_results_new(CMD_FAILURE,
-					"Failed to apply background configuration");
-			}
-		}
+	if (config->reading) {
+		// When reading the config file, we wait till the end to do a single
+		// modeset and swaybg spawn.
+		return cmd_results_new(CMD_SUCCESS, NULL);
+	}
+	request_modeset();
+
+	if (background && !spawn_swaybg()) {
+		return cmd_results_new(CMD_FAILURE,
+			"Failed to apply background configuration");
 	}
 
 	return cmd_results_new(CMD_SUCCESS, NULL);

sway/config.c

@@ -516,7 +516,7 @@ bool load_main_config(const char *file, bool is_active, bool validating) {
 	// Only really necessary if not explicitly `font` is set in the config.
 	config_update_font_height();
 
-	if (is_active && !validating) {
+	if (!validating) {
 		input_manager_verify_fallback_seat();
 
 		for (int i = 0; i < config->input_configs->length; i++) {
@@ -533,12 +533,14 @@ bool load_main_config(const char *file, bool is_active, bool validating) {
 		}
 		sway_switch_retrigger_bindings_for_all();
 
-		apply_stored_output_configs();
 		spawn_swaybg();
 
 		config->reloading = false;
-		if (config->swaynag_config_errors.client != NULL) {
-			swaynag_show(&config->swaynag_config_errors);
+		if (is_active) {
+			request_modeset();
+			if (config->swaynag_config_errors.client != NULL) {
+				swaynag_show(&config->swaynag_config_errors);
+			}
 		}
 	}