From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59831) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dp4OG-0008Ql-Pm for qemu-devel@nongnu.org; Mon, 04 Sep 2017 23:19:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dp4OC-0001cz-0w for qemu-devel@nongnu.org; Mon, 04 Sep 2017 23:19:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60390) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dp4OB-0001c0-Ns for qemu-devel@nongnu.org; Mon, 04 Sep 2017 23:18:59 -0400 Date: Tue, 5 Sep 2017 11:18:53 +0800 From: Fam Zheng Message-ID: <20170905031853.GN22515@lemon.lan> References: <20170901112829.2571-1-apahim@redhat.com> <20170901112829.2571-7-apahim@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170901112829.2571-7-apahim@redhat.com> Subject: Re: [Qemu-devel] [PATCH v8 06/13] qemu.py: make sure we only remove files we create List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amador Pahim Cc: qemu-devel@nongnu.org, stefanha@gmail.com, berrange@redhat.com, ehabkost@redhat.com, mreitz@redhat.com, kwolf@redhat.com, armbru@redhat.com, crosa@redhat.com, ldoktor@redhat.com On Fri, 09/01 13:28, Amador Pahim wrote: > To launch a VM, we need to create basically two files: the monitor > socket (if it's a UNIX socket) and the qemu log file. > > For the qemu log file, we currently just open the path, which will > create the file if it does not exist or overwrite the file if it does > exist. > > For the monitor socket, if it already exists, we are currently removing > it, even if it's not created by us. > > This patch moves to pre_launch() the responsibility to make sure we only > create files that are not pre-existent and to populate a list of > controlled files. This list will then be used as the reference of > files to remove during the cleanup (post_shutdown()). > > Signed-off-by: Amador Pahim > --- > scripts/qemu.py | 30 +++++++++++++++++++++++------- > 1 file changed, 23 insertions(+), 7 deletions(-) > > diff --git a/scripts/qemu.py b/scripts/qemu.py > index 3ebe5ee0a4..c26e1412f9 100644 > --- a/scripts/qemu.py > +++ b/scripts/qemu.py > @@ -41,6 +41,7 @@ class QEMUMachine(object): > monitor_address = os.path.join(test_dir, name + "-monitor.sock") > self._monitor_address = monitor_address > self._qemu_log_path = os.path.join(test_dir, name + ".log") > + self._qemu_log_fd = None > self._popen = None > self._binary = binary > self._args = list(args) # Force copy args in case we modify them > @@ -50,6 +51,7 @@ class QEMUMachine(object): > self._socket_scm_helper = socket_scm_helper > self._debug = debug > self._qemu_full_args = None > + self._created_files = [] > > # This can be used to add an unused monitor instance. > def add_monitor_telnet(self, ip, port): > @@ -128,30 +130,44 @@ class QEMUMachine(object): > '-display', 'none', '-vga', 'none'] > > def _pre_launch(self): > - self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, server=True, > - debug=self._debug) > + try: > + self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, > + server=True, > + debug=self._debug) > + except: > + raise What's the point of "except: raise"? It seems useless. > + else: > + if not isinstance(self._monitor_address, tuple): > + self._created_files.append(self._monitor_address) > + > + try: > + flags = os.O_CREAT | os.O_EXCL | os.O_WRONLY > + os.open(self._qemu_log_path, flags) Why change to os.open() instead of open()? > + except: > + raise > + else: > + self._created_files.append(self._qemu_log_path) > + self._qemu_log_fd = open(self._qemu_log_path, 'wb') > > def _post_launch(self): > self._qmp.accept() > > def _post_shutdown(self): > - if not isinstance(self._monitor_address, tuple): > - self._remove_if_exists(self._monitor_address) > - self._remove_if_exists(self._qemu_log_path) > + while self._created_files: > + self._remove_if_exists(self._created_files.pop()) > > def launch(self): > '''Launch the VM and establish a QMP connection''' > self._iolog = None > self._qemu_full_args = None > devnull = open(os.path.devnull, 'rb') > - qemulog = open(self._qemu_log_path, 'wb') > try: > self._pre_launch() > self._qemu_full_args = (self._wrapper + [self._binary] + > self._base_args() + self._args) > self._popen = subprocess.Popen(self._qemu_full_args, > stdin=devnull, > - stdout=qemulog, > + stdout=self._qemu_log_fd, > stderr=subprocess.STDOUT, > shell=False) > self._post_launch() > -- > 2.13.5 > Fam