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charset="utf-8" From: Adam Dorsey Expose the limit parameter of the underlying StreamReader and StreamWriter instances. This is helpful for the use case of transferring files in and out of a VM via the QEMU guest agent's guest-file-open, guest-file-read, guest-file-wri= te, and guest-file-close methods, as it allows pushing the buffer size up to the guest agent's limit of 48MB per transfer. Signed-off-by: Adam Dorsey cherry picked from commit 9ba6a698344eb3b570fa4864e906c54042824cd6 cherry picked from commit e4d0d3f835d82283ee0e48438d1b154e18303491 [Squashed in linter fixups. --js] Signed-off-by: John Snow Reviewed-by: Daniel P. Berrang=C3=A9 --- python/qemu/qmp/protocol.py | 25 ++++++++++++++++--------- python/qemu/qmp/qmp_client.py | 18 ++++++++++++++---- 2 files changed, 30 insertions(+), 13 deletions(-) diff --git a/python/qemu/qmp/protocol.py b/python/qemu/qmp/protocol.py index 958aeca08ac..3d5eb553aad 100644 --- a/python/qemu/qmp/protocol.py +++ b/python/qemu/qmp/protocol.py @@ -53,6 +53,9 @@ UnixAddrT =3D str SocketAddrT =3D Union[UnixAddrT, InternetAddrT] =20 +# Maximum allowable size of read buffer, default +_DEFAULT_READBUFLEN =3D 64 * 1024 + =20 class Runstate(Enum): """Protocol session runstate.""" @@ -202,22 +205,26 @@ class AsyncProtocol(Generic[T]): will log to 'qemu.qmp.protocol', but each individual connection can be given its own logger by giving it a name; messages will then log to 'qemu.qmp.protocol.${name}'. + :param readbuflen: + The maximum read buffer length of the underlying StreamReader + instance. """ # pylint: disable=3Dtoo-many-instance-attributes =20 #: Logger object for debugging messages from this connection. logger =3D logging.getLogger(__name__) =20 - # Maximum allowable size of read buffer - _limit =3D 64 * 1024 - # ------------------------- # Section: Public interface # ------------------------- =20 - def __init__(self, name: Optional[str] =3D None) -> None: + def __init__( + self, name: Optional[str] =3D None, + readbuflen: int =3D _DEFAULT_READBUFLEN + ) -> None: self._name: Optional[str] self.name =3D name + self.readbuflen =3D readbuflen =20 # stream I/O self._reader: Optional[StreamReader] =3D None @@ -574,7 +581,7 @@ async def _do_start_server(self, address: SocketAddrT, port=3Daddress[1], ssl=3Dssl, backlog=3D1, - limit=3Dself._limit, + limit=3Dself.readbuflen, ) else: coro =3D asyncio.start_unix_server( @@ -582,7 +589,7 @@ async def _do_start_server(self, address: SocketAddrT, path=3Daddress, ssl=3Dssl, backlog=3D1, - limit=3Dself._limit, + limit=3Dself.readbuflen, ) =20 # Allow runstate watchers to witness 'CONNECTING' state; some @@ -637,7 +644,7 @@ async def _do_connect(self, address: Union[SocketAddrT,= socket.socket], "fd=3D%d, family=3D%r, type=3D%r", address.fileno(), address.family, address.ty= pe) connect =3D asyncio.open_connection( - limit=3Dself._limit, + limit=3Dself.readbuflen, ssl=3Dssl, sock=3Daddress, ) @@ -647,14 +654,14 @@ async def _do_connect(self, address: Union[SocketAddr= T, socket.socket], address[0], address[1], ssl=3Dssl, - limit=3Dself._limit, + limit=3Dself.readbuflen, ) else: self.logger.debug("Connecting to file://%s ...", address) connect =3D asyncio.open_unix_connection( path=3Daddress, ssl=3Dssl, - limit=3Dself._limit, + limit=3Dself.readbuflen, ) =20 self._reader, self._writer =3D await connect diff --git a/python/qemu/qmp/qmp_client.py b/python/qemu/qmp/qmp_client.py index a87fb565ab5..d826331b6d5 100644 --- a/python/qemu/qmp/qmp_client.py +++ b/python/qemu/qmp/qmp_client.py @@ -170,6 +170,12 @@ class QMPClient(AsyncProtocol[Message], Events): =20 :param name: Optional nickname for the connection, used for logging. =20 + :param readbuflen: + The maximum buffer length for reads and writes to and from the QMP + server, in bytes. Default is 10MB. If `QMPClient` is used to + connect to a guest agent to transfer files via ``guest-file-read``/ + ``guest-file-write``, increasing this value may be required. + Basic script-style usage looks like this:: =20 qmp =3D QMPClient('my_virtual_machine_name') @@ -203,14 +209,18 @@ async def run(self, address=3D'/tmp/qemu.socket'): #: Logger object used for debugging messages. logger =3D logging.getLogger(__name__) =20 - # Read buffer limit; 10MB like libvirt default - _limit =3D 10 * 1024 * 1024 + # Read buffer default limit; 10MB like libvirt default + _readbuflen =3D 10 * 1024 * 1024 =20 # Type alias for pending execute() result items _PendingT =3D Union[Message, ExecInterruptedError] =20 - def __init__(self, name: Optional[str] =3D None) -> None: - super().__init__(name) + def __init__( + self, + name: Optional[str] =3D None, + readbuflen: int =3D _readbuflen + ) -> None: + super().__init__(name, readbuflen) Events.__init__(self) =20 #: Whether or not to await a greeting after establishing a connect= ion. --=20 2.50.1