| Message ID | 20210917054047.2042843-8-jsnow@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Switch iotests to using Async QMP | expand |
On 17.09.21 07:40, John Snow wrote: > The single space is indeed required to successfully transmit the file > descriptor to QEMU. Yeah, socket_scm_helper.c said “Send a blank to notify qemu”. > Signed-off-by: John Snow <jsnow@redhat.com> > --- > python/qemu/aqmp/qmp_client.py | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/python/qemu/aqmp/qmp_client.py b/python/qemu/aqmp/qmp_client.py > index d2ad7459f9..58f85990bc 100644 > --- a/python/qemu/aqmp/qmp_client.py > +++ b/python/qemu/aqmp/qmp_client.py > @@ -9,6 +9,8 @@ > > import asyncio > import logging > +import socket > +import struct > from typing import ( > Dict, > List, > @@ -624,3 +626,18 @@ async def execute(self, cmd: str, > """ > msg = self.make_execute_msg(cmd, arguments, oob=oob) > return await self.execute_msg(msg) > + > + @upper_half > + @require(Runstate.RUNNING) > + def send_fd_scm(self, fd: int) -> None: > + """ > + Send a file descriptor to the remote via SCM_RIGHTS. > + """ > + assert self._writer is not None > + sock = self._writer.transport.get_extra_info('socket') > + > + # Python 3.9+ adds socket.send_fds(...) > + sock.sendmsg( > + [b' '], > + [(socket.SOL_SOCKET, socket.SCM_RIGHTS, struct.pack('@i', fd))] > + ) AFAIU the socket can be either TCP or a UNIX socket (AsyncProtocol._do_accept’s docstring sounds this way), so should we check that this is a UNIX socket? (Or is it fine to just run into the error that I suspect we would get with a TCP socket?) Hanna
On Fri, Sep 17, 2021 at 9:34 AM Hanna Reitz <hreitz@redhat.com> wrote: > On 17.09.21 07:40, John Snow wrote: > > The single space is indeed required to successfully transmit the file > > descriptor to QEMU. > > Yeah, socket_scm_helper.c said “Send a blank to notify qemu”. > > > Signed-off-by: John Snow <jsnow@redhat.com> > > --- > > python/qemu/aqmp/qmp_client.py | 17 +++++++++++++++++ > > 1 file changed, 17 insertions(+) > > > > diff --git a/python/qemu/aqmp/qmp_client.py > b/python/qemu/aqmp/qmp_client.py > > index d2ad7459f9..58f85990bc 100644 > > --- a/python/qemu/aqmp/qmp_client.py > > +++ b/python/qemu/aqmp/qmp_client.py > > @@ -9,6 +9,8 @@ > > > > import asyncio > > import logging > > +import socket > > +import struct > > from typing import ( > > Dict, > > List, > > @@ -624,3 +626,18 @@ async def execute(self, cmd: str, > > """ > > msg = self.make_execute_msg(cmd, arguments, oob=oob) > > return await self.execute_msg(msg) > > + > > + @upper_half > > + @require(Runstate.RUNNING) > > + def send_fd_scm(self, fd: int) -> None: > > + """ > > + Send a file descriptor to the remote via SCM_RIGHTS. > > + """ > > + assert self._writer is not None > > + sock = self._writer.transport.get_extra_info('socket') > > + > > + # Python 3.9+ adds socket.send_fds(...) > > + sock.sendmsg( > > + [b' '], > > + [(socket.SOL_SOCKET, socket.SCM_RIGHTS, struct.pack('@i', > fd))] > > + ) > > AFAIU the socket can be either TCP or a UNIX socket > (AsyncProtocol._do_accept’s docstring sounds this way), so should we > check that this is a UNIX socket? (Or is it fine to just run into the > error that I suspect we would get with a TCP socket?) > > Hanna > > Uhh, hm. I was going to say "Yeah, just let it fail!" but ... upon going to document what error to expect in this case, I am realizing it fails silently. So, uh, that's not ideal. I'll fix this to make it bark. --js
diff --git a/python/qemu/aqmp/qmp_client.py b/python/qemu/aqmp/qmp_client.py index d2ad7459f9..58f85990bc 100644 --- a/python/qemu/aqmp/qmp_client.py +++ b/python/qemu/aqmp/qmp_client.py @@ -9,6 +9,8 @@ import asyncio import logging +import socket +import struct from typing import ( Dict, List, @@ -624,3 +626,18 @@ async def execute(self, cmd: str, """ msg = self.make_execute_msg(cmd, arguments, oob=oob) return await self.execute_msg(msg) + + @upper_half + @require(Runstate.RUNNING) + def send_fd_scm(self, fd: int) -> None: + """ + Send a file descriptor to the remote via SCM_RIGHTS. + """ + assert self._writer is not None + sock = self._writer.transport.get_extra_info('socket') + + # Python 3.9+ adds socket.send_fds(...) + sock.sendmsg( + [b' '], + [(socket.SOL_SOCKET, socket.SCM_RIGHTS, struct.pack('@i', fd))] + )
The single space is indeed required to successfully transmit the file descriptor to QEMU. Signed-off-by: John Snow <jsnow@redhat.com> --- python/qemu/aqmp/qmp_client.py | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)