Re: [Qemu-devel] [PATCH 7/9] slirp: Add sockaddr_equal, make solookup family-agnostic

From: Samuel Thibault <samuel.thibault@gnu.org>
To: Thomas Huth <thuth@redhat.com>
Cc: zhanghailiang <zhang.zhanghailiang@huawei.com>,
	Li Zhijian <lizhijian@cn.fujitsu.com>,
	Stefan Hajnoczi <stefanha@gmail.com>,
	Jason Wang <jasowang@redhat.com>,
	qemu-devel@nongnu.org, Vasiliy Tolstov <v.tolstov@selfip.ru>,
	Dave Gilbert <dgilbert@redhat.com>,
	Gonglei <arei.gonglei@huawei.com>,
	Jan Kiszka <jan.kiszka@siemens.com>,
	Huangpeng <peter.huangpeng@huawei.com>,
	Yang Hongyang <yanghy@cn.fujitsu.com>,
	Guillaume Subiron <maethor@subiron.org>
Subject: Re: [Qemu-devel] [PATCH 7/9] slirp: Add sockaddr_equal, make solookup family-agnostic
Date: Mon, 14 Dec 2015 23:24:01 +0100	[thread overview]
Message-ID: <20151214222401.GC2967@var.home> (raw)
In-Reply-To: <566F23CF.4050701@redhat.com>

Thomas Huth, on Mon 14 Dec 2015 21:17:19 +0100, wrote:
> > +	lhost.ss_family = AF_INET;
> > +	((struct sockaddr_in *)&lhost)->sin_addr = ti->ti_src;
> > +	((struct sockaddr_in *)&lhost)->sin_port = ti->ti_sport;
> > +	fhost.ss_family = AF_INET;
> > +	((struct sockaddr_in *)&fhost)->sin_addr = ti->ti_dst;
> > +	((struct sockaddr_in *)&fhost)->sin_port = ti->ti_dport;
> 
> Couldn't you simply use "fhost.sin.sin_addr = ..." etc. instead of
> casting everything via a pointer?

No, here fhost is a struct sockaddr_storage, which doesn't have a sin
field.  We could define a struct sockaddr_in *fhost4 that would be made
an alias to fhost, but I don't feel it's more readable to introduce an
alias than expliciting those two casts.

Samuel