From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <vdavydov.dev@gmail.com>
Date: Tue, 14 May 2019 11:09:32 +0300
From: Vladimir Davydov <vdavydov.dev@gmail.com>
Subject: Re: [tarantool-patches] [PATCH 3/3] sio: optimize sio_strfaddr() for
 the most common case
Message-ID: <20190514080932.czhcqcl6t6dy6sv3@esperanza>
References: <cover.1556470563.git.v.shpilevoy@tarantool.org>
 <01f8b95e78623d7f56cded96324184b8d96cec13.1556470563.git.v.shpilevoy@tarantool.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <01f8b95e78623d7f56cded96324184b8d96cec13.1556470563.git.v.shpilevoy@tarantool.org>
To: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
Cc: tarantool-patches@freelists.org, kostja@tarantool.org
List-ID: <tarantool-patches.dev.tarantool.org>

On Sun, Apr 28, 2019 at 07:56:27PM +0300, Vladislav Shpilevoy wrote:
> The main motivation behind this commit is that SWIM makes active
> use of sio_strfaddr() for logging - for each received/sent
> message it writes a couple of addresses into a log. It does it in
> verbose mode, but the say() function arguments are still
> calculated even when the active mode is lower than verbose.

They are not as say() is a macro.

At compile time

  say(level, error, format, ...)

is expanded into

  if (say_log_level_is_enabled(level))
          _say(level, file, line, error, format, ...);

That is, neither format nor its arguments are evaluated at runtime
unless say_log_level_is_enabled(level) returns true.