feat: add exit code propagation on errors

lualib/bootstrap.lua

@@ -32,8 +32,11 @@ local function start(config)
 end
 
 local function wait(ctx)
-	boot.wait(ctx)
+	local exitcode = boot.wait(ctx)
 	boot.deinit()
+	if exitcode ~= 0 then
+		os.exit(exitcode, true)
+	end
 end
 
 return {

service/root.lua

@@ -14,6 +14,8 @@ local RECEIPT_ERROR <const> = 2
 local RECEIPT_BLOCK <const> = 3
 local RECEIPT_RESPONSE <const> = 4
 
+local EXIT_CODE_ERROR <const> = 1
+
 local S = {}
 
 local anonymous_services = {}
@@ -42,6 +44,7 @@ do
 		if type == MESSAGE_ERROR then
 			ltask.log.error("Root fatal:", table.concat(errobj, "\n"))
 			writelog()
+			root.set_exit_code(EXIT_CODE_ERROR)
 			root_quit()
 		end
 	end

src/ltask.c

@@ -106,6 +106,7 @@ struct ltask {
 	atomic_int thread_count;
 	int blocked_service;		// binding service may block
 	FILE *logfile;
+	int exit_code;			// process exit code, set by root service
 };
 
 struct service_ud {
@@ -974,8 +975,10 @@ ltask_wait(lua_State *L) {
 	}
 	message_delete(ctx->task->external_last_message);
 	queue_delete(ctx->task->external_message);
+	int exit_code = ctx->task->exit_code;
 	mainthread_deinit(&ctx->task->mt);
-	return 0;
+	lua_pushinteger(L, exit_code);
+	return 1;
 }
 
 static int
@@ -1735,6 +1738,14 @@ lmainthread_yield(lua_State *L) {
 	return mainthread_change_status(L, MAINTHREAD_STATUS_YIELD);
 }
 
+static int
+ltask_set_exit_code(lua_State *L) {
+	const struct service_ud *S = getS(L);
+	int code = (int)luaL_checkinteger(L, 1);
+	S->task->exit_code = code;
+	return 0;
+}
+
 LUAMOD_API int
 luaopen_ltask(lua_State *L) {
 	luaL_checkversion(L);
@@ -1881,6 +1892,7 @@ luaopen_ltask_root(lua_State *L) {
 	luaL_Reg l[] = {
 		{ "init_service", ltask_initservice },
 		{ "close_service", ltask_closeservice },
+		{ "set_exit_code", ltask_set_exit_code },
 		{ NULL, NULL },
 	};