Received: from eggs.gnu.org ([2001:4830:134:3::10]:60987) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f1fGV-0001ha-Lp for qemu-devel@nongnu.org; Thu, 29 Mar 2018 17:39:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f1fGU-0008M4-QX for qemu-devel@nongnu.org; Thu, 29 Mar 2018 17:39:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56102) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f1fGU-0008Ja-Kr for qemu-devel@nongnu.org; Thu, 29 Mar 2018 17:39:22 -0400 From: Eduardo Habkost Date: Thu, 29 Mar 2018 18:38:42 -0300 Message-Id: <20180329213857.15499-4-ehabkost@redhat.com> In-Reply-To: <20180329213857.15499-1-ehabkost@redhat.com> References: <20180329213857.15499-1-ehabkost@redhat.com> Subject: [Qemu-devel] [RFC 03/18] qmp.py: Cleanly handle unexpectedly closed socket List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Thomas Huth , Paolo Bonzini , Cleber Rosa , Markus Armbruster , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Marcel Apfelbaum , Amador Pahim QEMUMonitorProtocol.cmd() returns None if the socket was closed, so callers must handle this case explicltly. Signed-off-by: Eduardo Habkost --- scripts/qmp/qmp.py | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/scripts/qmp/qmp.py b/scripts/qmp/qmp.py index e9cb6b2683..91b537ea04 100644 --- a/scripts/qmp/qmp.py +++ b/scripts/qmp/qmp.py @@ -73,6 +73,8 @@ class QEMUMonitorProtocol(object): raise QMPConnectError # Greeting seems ok, negotiate capabilities resp = self.cmd('qmp_capabilities') + if resp is None: + raise QMPConnectError("QMP connection unexpectedly closed") if "return" in resp: return greeting raise QMPCapabilitiesError @@ -182,6 +184,8 @@ class QEMUMonitorProtocol(object): @param name: command name (string) @param args: command arguments (dict) @param cmd_id: command id (dict, list, string or int) + @return QMP response as a Python dict or None if the connection has + been closed """ qmp_cmd = {'execute': name} if args: @@ -195,6 +199,8 @@ class QEMUMonitorProtocol(object): Build and send a QMP command to the monitor, report errors if any """ ret = self.cmd(cmd, kwds) + if ret is None: + raise QMPConnectError("QMP connection unexpectedly closed") if "error" in ret: raise Exception(ret['error']['desc']) return ret['return'] -- 2.14.3