From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59478) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1UH9-0005BM-PN for qemu-devel@nongnu.org; Fri, 21 Apr 2017 04:50:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d1UH8-0007dv-QL for qemu-devel@nongnu.org; Fri, 21 Apr 2017 04:50:47 -0400 Date: Fri, 21 Apr 2017 16:50:34 +0800 From: Fam Zheng Message-ID: <20170421085034.GD8342@lemon.lan> References: <20170420040003.31074-1-famz@redhat.com> <20170420153016.GI3227@redhat.com> <20170420203250.GI4747@noname.redhat.com> <87pog61fjr.fsf@dusky.pond.sub.org> <20170421083137.GD27925@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170421083137.GD27925@redhat.com> Subject: Re: [Qemu-devel] [PATCH] sheepdog: Set error when connection fails List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Markus Armbruster , Kevin Wolf , sheepdog@lists.wpkg.org, qemu-block@nongnu.org, Hitoshi Mitake , Jeff Cody , qemu-devel@nongnu.org, Max Reitz , Liu Yuan On Fri, 04/21 09:31, Daniel P. Berrange wrote: > On Fri, Apr 21, 2017 at 07:43:36AM +0200, Markus Armbruster wrote: > > Kevin Wolf writes: > > > > > Am 20.04.2017 um 17:30 hat Daniel P. Berrange geschrieben: > > >> On Thu, Apr 20, 2017 at 12:00:03PM +0800, Fam Zheng wrote: > > >> > Signed-off-by: Fam Zheng > > >> > --- > > >> > block/sheepdog.c | 1 + > > >> > 1 file changed, 1 insertion(+) > > >> > > > >> > diff --git a/block/sheepdog.c b/block/sheepdog.c > > >> > index fb9203e..7e889ee 100644 > > >> > --- a/block/sheepdog.c > > >> > +++ b/block/sheepdog.c > > >> > @@ -608,6 +608,7 @@ static int connect_to_sdog(BDRVSheepdogState *s, Error **errp) > > >> > qemu_set_nonblock(fd); > > >> > } else { > > >> > fd = -EIO; > > >> > + error_setg(errp, "Failed to connect to sheepdog server"); > > >> > } > > >> > > >> This doesn't make much sense to me. The lines just above the > > >> diff context have this: > > >> > > >> fd = socket_connect(s->addr, errp, NULL, NULL); > > >> > > >> socket_connect should have already reported an error on "errp" > > >> in the scenario that 'fd == -1'. > > > > > > By the way, am I the only one who thinks that having errp anywhere else > > > than as the last argument is bad style? I can easily see myself missing > > > that this functions sets it because the last argument is NULL. > > > > Yes, it's bad style because it's suprising. Worth fixing. > > In fact we can simply delete the last two arguments to socket_connect() > entirely. Most code is now switched over to use QIOChannel APIs, so we > don't have anything which uses the non-blocking connect feature of > socket_connect() anymore. There is one caller that passes non-NULL last two parameters, which seems non-trivial to convert: static int net_socket_connect_init(NetClientState *peer, const char *model, const char *name, const char *host_str) { socket_connect_data *c = g_new0(socket_connect_data, 1); int fd = -1; Error *local_error = NULL; c->peer = peer; c->model = g_strdup(model); c->name = g_strdup(name); c->saddr = socket_parse(host_str, &local_error); if (c->saddr == NULL) { goto err; } fd = socket_connect(c->saddr, net_socket_connected, c, &local_error); if (fd < 0) { goto err; } return 0; err: error_report_err(local_error); socket_connect_data_free(c); return -1; }