lua: set lua_atpanic with custom handler

Set lua_atpanic with handler which prints line and file
where panic occured

But in some cases luajit doesn't call this function, though
program fails

Investigation shows that it happens inside unwind library

src/lua/init.c

@@ -314,6 +314,16 @@ tarantool_lua_setpaths(struct lua_State *L)
 	lua_pop(L, 1); /* package */
 }
 
+static int
+tarantool_panic_handler(lua_State *L) {
+	const char *problem = lua_tostring(L, -1);
+	lua_Debug ar;
+	lua_getstack(L, 1, &ar);
+	lua_getinfo(L, "nSl", &ar);
+	say_crit("%s at %s:%d \n", problem, ar.short_src, ar.currentline);
+	return 1;
+}
+
 static int
 luaopen_tarantool(lua_State *L)
 {
@@ -377,7 +387,6 @@ tarantool_lua_init(const char *tarantool_bin, int argc, char **argv)
 	/* Initialize ffi to enable luaL_pushcdata/luaL_checkcdata functions */
 	luaL_loadstring(L, "return require('ffi')");
 	lua_call(L, 0, 0);
-
 	lua_register(L, "tonumber64", lbox_tonumber64);
 
 	tarantool_lua_utils_init(L);
@@ -446,6 +455,7 @@ tarantool_lua_init(const char *tarantool_bin, int argc, char **argv)
 		panic("Failed to unload 'strict' Lua module");
 #endif /* NDEBUG */
 
+	lua_atpanic(L, tarantool_panic_handler);
 	/* clear possible left-overs of init */
 	lua_settop(L, 0);
 	tarantool_L = L;
@@ -590,6 +600,7 @@ tarantool_lua_run_script(char *path, bool interactive,
 	 * To work this problem around we must run init script in
 	 * a separate fiber.
 	 */
+
 	script_fiber = fiber_new(title, run_script_f);
 	if (script_fiber == NULL)
 		panic("%s", diag_last_error(diag_get())->errmsg);