| Message ID | 20200715204814.2630-3-robert.foley@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | python/qemu: follow-up changes for ConsoleSocket | expand |
Robert Foley <robert.foley@linaro.org> writes: > The primary purpose of this change is to clean up > machine.py's console_socket property to return a single type, > a ConsoleSocket. > > ConsoleSocket now derives from a socket, which means that > in the default case (of not draining), machine.py > will see the same behavior as it did prior to ConsoleSocket. > > Signed-off-by: Robert Foley <robert.foley@linaro.org> > --- > python/qemu/console_socket.py | 81 +++++++++++++++++++++-------------- > python/qemu/machine.py | 13 ++---- > 2 files changed, 54 insertions(+), 40 deletions(-) > > diff --git a/python/qemu/console_socket.py b/python/qemu/console_socket.py > index 6a746c1dbf..475de5b101 100644 > --- a/python/qemu/console_socket.py > +++ b/python/qemu/console_socket.py > @@ -13,68 +13,76 @@ which can drain a socket and optionally dump the bytes to file. > # the COPYING file in the top-level directory. > # > > -import asyncore > import socket > import threading > from collections import deque > import time > > > -class ConsoleSocket(asyncore.dispatcher): > +class ConsoleSocket(socket.socket): > """ > ConsoleSocket represents a socket attached to a char device. > > - Drains the socket and places the bytes into an in memory buffer > - for later processing. > + Optionally (if drain==True), drains the socket and places the bytes > + into an in memory buffer for later processing. > > Optionally a file path can be passed in and we will also > dump the characters to this file for debugging purposes. > """ > - def __init__(self, address, file=None): > + def __init__(self, address, file=None, drain=False): > self._recv_timeout_sec = 300 > self._sleep_time = 0.5 > self._buffer = deque() > - self._asyncore_thread = None > - self._sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) > - self._sock.connect(address) > + self._drain_thread = None > + socket.socket.__init__(self, socket.AF_UNIX, socket.SOCK_STREAM) > + self.connect(address) > + self._drain = drain We end up with two variables that represent the fact we have draining happening. Could we rationalise it into: if drain: self._drain_thread = self._thread_start() else self._drain_thread = None # if this is needed And then tests for: if not self._drain: become if self._drain_thread is None: > self._logfile = None > if file: > self._logfile = open(file, "w") > - asyncore.dispatcher.__init__(self, sock=self._sock) > self._open = True > - self._thread_start() > + if drain: > + self._thread_start() > + > + def _drain_fn(self): > + """Drains the socket and runs while the socket is open.""" > + while self._open: > + try: > + self._drain_socket() > + except socket.timeout: > + # The socket is expected to timeout since we set a > + # short timeout to allow the thread to exit when > + # self._open is set to False. > + time.sleep(self._sleep_time) > > def _thread_start(self): > - """Kick off a thread to wait on the asyncore.loop""" > - if self._asyncore_thread is not None: > + """Kick off a thread to drain the socket.""" > + if self._drain_thread is not None: > return > - self._asyncore_thread = threading.Thread(target=asyncore.loop, > - kwargs={'timeout':1}) > - self._asyncore_thread.daemon = True > - self._asyncore_thread.start() > - > - def handle_close(self): > - """redirect close to base class""" > - # Call the base class close, but not self.close() since > - # handle_close() occurs in the context of the thread which > - # self.close() attempts to join. > - asyncore.dispatcher.close(self) > + # Configure socket to not block and timeout. > + # This allows our drain thread to not block > + # on recieve and exit smoothly. > + socket.socket.setblocking(self, 0) > + socket.socket.settimeout(self, 1) > + self._drain_thread = threading.Thread(target=self._drain_fn) > + self._drain_thread.daemon = True > + self._drain_thread.start() > > def close(self): > """Close the base object and wait for the thread to terminate""" > if self._open: > self._open = False > - asyncore.dispatcher.close(self) > - if self._asyncore_thread is not None: > - thread, self._asyncore_thread = self._asyncore_thread, None > + if self._drain and self._drain_thread is not None: > + thread, self._drain_thread = self._drain_thread, None Would self._drain ever not have self._drain_thread set? > thread.join() > + socket.socket.close(self) <snip> > diff --git a/python/qemu/machine.py b/python/qemu/machine.py > index 6769359766..62709d86e4 100644 > --- a/python/qemu/machine.py > +++ b/python/qemu/machine.py > @@ -22,7 +22,6 @@ import logging > import os > import subprocess > import shutil > -import socket FYI minor patch conflict here with master > import tempfile > from typing import Optional, Type > from types import TracebackType > @@ -591,12 +590,8 @@ class QEMUMachine: > Returns a socket connected to the console > """ > if self._console_socket is None: > - if self._drain_console: > - self._console_socket = console_socket.ConsoleSocket( > - self._console_address, > - file=self._console_log_path) > - else: > - self._console_socket = socket.socket(socket.AF_UNIX, > - socket.SOCK_STREAM) > - self._console_socket.connect(self._console_address) > + self._console_socket = console_socket.ConsoleSocket( > + self._console_address, > + file=self._console_log_path, > + drain=self._drain_console) > return self._console_socket
On Thu, 16 Jul 2020 at 09:42, Alex Bennée <alex.bennee@linaro.org> wrote: > <snip> > > + self._drain_thread = None > > + socket.socket.__init__(self, socket.AF_UNIX, socket.SOCK_STREAM) > > + self.connect(address) > > + self._drain = drain > > We end up with two variables that represent the fact we have draining > happening. Could we rationalise it into: > > if drain: > self._drain_thread = self._thread_start() > else > self._drain_thread = None # if this is needed > > And then tests for: > > if not self._drain: > > become > > if self._drain_thread is None: Good point, this is simpler. Will update. <snip> > > + if self._drain and self._drain_thread is not None: > > + thread, self._drain_thread = self._drain_thread, None > Would self._drain ever not have self._drain_thread set? No, I believe that if drain is set, it results in _drain_thread also being set. This will be cleaned up once we drop the _drain. > > > thread.join() > > + socket.socket.close(self) > <snip> > > diff --git a/python/qemu/machine.py b/python/qemu/machine.py > > index 6769359766..62709d86e4 100644 > > --- a/python/qemu/machine.py > > +++ b/python/qemu/machine.py > > @@ -22,7 +22,6 @@ import logging > > import os > > import subprocess > > import shutil > > -import socket > > FYI minor patch conflict here with master OK, will rebase and fix this conflict. Thanks & Regards, -Rob > > > import tempfile > > from typing import Optional, Type > > from types import TracebackType > > @@ -591,12 +590,8 @@ class QEMUMachine: > > Returns a socket connected to the console > > """ > > if self._console_socket is None: > > - if self._drain_console: > > - self._console_socket = console_socket.ConsoleSocket( > > - self._console_address, > > - file=self._console_log_path) > > - else: > > - self._console_socket = socket.socket(socket.AF_UNIX, > > - socket.SOCK_STREAM) > > - self._console_socket.connect(self._console_address) > > + self._console_socket = console_socket.ConsoleSocket( > > + self._console_address, > > + file=self._console_log_path, > > + drain=self._drain_console) > > return self._console_socket > > > -- > Alex Bennée
diff --git a/python/qemu/console_socket.py b/python/qemu/console_socket.py index 6a746c1dbf..475de5b101 100644 --- a/python/qemu/console_socket.py +++ b/python/qemu/console_socket.py @@ -13,68 +13,76 @@ which can drain a socket and optionally dump the bytes to file. # the COPYING file in the top-level directory. # -import asyncore import socket import threading from collections import deque import time -class ConsoleSocket(asyncore.dispatcher): +class ConsoleSocket(socket.socket): """ ConsoleSocket represents a socket attached to a char device. - Drains the socket and places the bytes into an in memory buffer - for later processing. + Optionally (if drain==True), drains the socket and places the bytes + into an in memory buffer for later processing. Optionally a file path can be passed in and we will also dump the characters to this file for debugging purposes. """ - def __init__(self, address, file=None): + def __init__(self, address, file=None, drain=False): self._recv_timeout_sec = 300 self._sleep_time = 0.5 self._buffer = deque() - self._asyncore_thread = None - self._sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) - self._sock.connect(address) + self._drain_thread = None + socket.socket.__init__(self, socket.AF_UNIX, socket.SOCK_STREAM) + self.connect(address) + self._drain = drain self._logfile = None if file: self._logfile = open(file, "w") - asyncore.dispatcher.__init__(self, sock=self._sock) self._open = True - self._thread_start() + if drain: + self._thread_start() + + def _drain_fn(self): + """Drains the socket and runs while the socket is open.""" + while self._open: + try: + self._drain_socket() + except socket.timeout: + # The socket is expected to timeout since we set a + # short timeout to allow the thread to exit when + # self._open is set to False. + time.sleep(self._sleep_time) def _thread_start(self): - """Kick off a thread to wait on the asyncore.loop""" - if self._asyncore_thread is not None: + """Kick off a thread to drain the socket.""" + if self._drain_thread is not None: return - self._asyncore_thread = threading.Thread(target=asyncore.loop, - kwargs={'timeout':1}) - self._asyncore_thread.daemon = True - self._asyncore_thread.start() - - def handle_close(self): - """redirect close to base class""" - # Call the base class close, but not self.close() since - # handle_close() occurs in the context of the thread which - # self.close() attempts to join. - asyncore.dispatcher.close(self) + # Configure socket to not block and timeout. + # This allows our drain thread to not block + # on recieve and exit smoothly. + socket.socket.setblocking(self, 0) + socket.socket.settimeout(self, 1) + self._drain_thread = threading.Thread(target=self._drain_fn) + self._drain_thread.daemon = True + self._drain_thread.start() def close(self): """Close the base object and wait for the thread to terminate""" if self._open: self._open = False - asyncore.dispatcher.close(self) - if self._asyncore_thread is not None: - thread, self._asyncore_thread = self._asyncore_thread, None + if self._drain and self._drain_thread is not None: + thread, self._drain_thread = self._drain_thread, None thread.join() + socket.socket.close(self) if self._logfile: self._logfile.close() self._logfile = None - def handle_read(self): + def _drain_socket(self): """process arriving characters into in memory _buffer""" - data = asyncore.dispatcher.recv(self, 1) + data = socket.socket.recv(self, 1) # latin1 is needed since there are some chars # we are receiving that cannot be encoded to utf-8 # such as 0xe2, 0x80, 0xA6. @@ -89,6 +97,9 @@ class ConsoleSocket(asyncore.dispatcher): """Return chars from in memory buffer. Maintains the same API as socket.socket.recv. """ + if not self._drain: + # Not buffering the socket, pass thru to socket. + return socket.socket.recv(self, buffer_size) start_time = time.time() while len(self._buffer) < buffer_size: time.sleep(self._sleep_time) @@ -102,9 +113,17 @@ class ConsoleSocket(asyncore.dispatcher): # socket w/o our intervention. return chars.encode("latin1") - def set_blocking(self): - """Maintain compatibility with socket API""" + def setblocking(self, value): + """When not draining we pass thru to the socket, + since when draining we control socket blocking. + """ + if not self._drain: + socket.socket.setblocking(self, value) def settimeout(self, seconds): - """Set current timeout on recv""" + """When not draining we pass thru to the socket, + since when draining we control the timeout. + """ self._recv_timeout_sec = seconds + if not self._drain: + socket.socket.settimeout(self, seconds) diff --git a/python/qemu/machine.py b/python/qemu/machine.py index 6769359766..62709d86e4 100644 --- a/python/qemu/machine.py +++ b/python/qemu/machine.py @@ -22,7 +22,6 @@ import logging import os import subprocess import shutil -import socket import tempfile from typing import Optional, Type from types import TracebackType @@ -591,12 +590,8 @@ class QEMUMachine: Returns a socket connected to the console """ if self._console_socket is None: - if self._drain_console: - self._console_socket = console_socket.ConsoleSocket( - self._console_address, - file=self._console_log_path) - else: - self._console_socket = socket.socket(socket.AF_UNIX, - socket.SOCK_STREAM) - self._console_socket.connect(self._console_address) + self._console_socket = console_socket.ConsoleSocket( + self._console_address, + file=self._console_log_path, + drain=self._drain_console) return self._console_socket
The primary purpose of this change is to clean up machine.py's console_socket property to return a single type, a ConsoleSocket. ConsoleSocket now derives from a socket, which means that in the default case (of not draining), machine.py will see the same behavior as it did prior to ConsoleSocket. Signed-off-by: Robert Foley <robert.foley@linaro.org> --- python/qemu/console_socket.py | 81 +++++++++++++++++++++-------------- python/qemu/machine.py | 13 ++---- 2 files changed, 54 insertions(+), 40 deletions(-)