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Differential D1018

selectors2: do not use platform.system()
ClosedPublic

Authored by quark on Oct 11 2017, 8:57 PM.

Details

Reviewers
lothiraldan
Group Reviewers
hg-reviewers
Commits
rHGa568a46751b6: selectors2: do not use platform.system()
Summary

platform.system() may have a side effect spawning a shell executing
uname -p, which may print a warning when the current directory is removed:

shell-init: error retrieving current directory: getcwd: cannot access parent directories: No such file or directory

This patch changes selectors2 to test the sys.platform string, which is a
much safer way to detect Jython.

Jython's sys.platform looks like this:

Jython 2.7.1 (default:0df7adb1b397, Jun 30 2017, 19:02:43)
[OpenJDK 64-Bit Server VM (Oracle Corporation)] on java1.8.0_144
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.platform
'java1.8.0_144 ( ==linux2 for targets )'

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

quark created this revision.Oct 11 2017, 8:57 PM
quark added a child revision: D1019: logtoprocess: do not use platform.system().Oct 11 2017, 8:57 PM
quark edited the summary of this revision. (Show Details)
quark updated this revision to Diff 2609.Oct 11 2017, 9:00 PM
quark updated this revision to Diff 2633.Oct 12 2017, 12:37 PM
quark updated this revision to Diff 2651.Oct 12 2017, 10:21 PM
Closed by commit rHGa568a46751b6: selectors2: do not use platform.system() (authored by quark). · Explain WhyOct 13 2017, 10:05 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/pycompat.py (2 lines)
Mmercurial/selectors2.py (7 lines)

Diff 2677

mercurial/pycompat.py

sysargv = sys.argv sysargv = sys.argv
sysplatform = sys.platform sysplatform = sys.platform
getcwd = os.getcwd getcwd = os.getcwd
sysexecutable = sys.executable sysexecutable = sys.executable
shlexsplit = shlex.split shlexsplit = shlex.split
stringio = cStringIO.StringIO stringio = cStringIO.StringIO
maplist = map maplist = map
rawinput = raw_input rawinput = raw_input
isjython = sysplatform.startswith('java')

mercurial/selectors2.py

# no-check-code # no-check-code
from __future__ import absolute_import from __future__ import absolute_import
import collections import collections
import errno import errno
import math import math
import platform
import select import select
import socket import socket
import sys import sys
import time import time
from . import pycompat
namedtuple = collections.namedtuple namedtuple = collections.namedtuple
Mapping = collections.Mapping Mapping = collections.Mapping
try: try:
monotonic = time.monotonic monotonic = time.monotonic
except AttributeError: except AttributeError:
monotonic = time.time monotonic = time.time
def _wrap_select(self, r, w, timeout=None): def _wrap_select(self, r, w, timeout=None):
""" Wrapper for select.select because timeout is a positional arg """ """ Wrapper for select.select because timeout is a positional arg """
return select.select(r, w, [], timeout) return select.select(r, w, [], timeout)
__all__.append('SelectSelector') __all__.append('SelectSelector')
# Jython has a different implementation of .fileno() for socket objects. # Jython has a different implementation of .fileno() for socket objects.
if platform.system() == 'Java': if pycompat.isjython:
class _JythonSelectorMapping(object): class _JythonSelectorMapping(object):
""" This is an implementation of _SelectorMapping that is built """ This is an implementation of _SelectorMapping that is built
for use specifically with Jython, which does not provide a hashable for use specifically with Jython, which does not provide a hashable
value from socket.socket.fileno(). """ value from socket.socket.fileno(). """
def __init__(self, selector): def __init__(self, selector):
assert isinstance(selector, JythonSelectSelector) assert isinstance(selector, JythonSelectSelector)
self._selector = selector self._selector = selector
# kqueue == devpoll == epoll > poll > select # kqueue == devpoll == epoll > poll > select
# select() also can't accept a FD > FD_SETSIZE (usually around 1024) # select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector(): def DefaultSelector():
""" This function serves as a first call for DefaultSelector to """ This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """ by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None: if _DEFAULT_SELECTOR is None:
if platform.system() == 'Java': # Platform-specific: Jython if pycompat.isjython:
_DEFAULT_SELECTOR = JythonSelectSelector _DEFAULT_SELECTOR = JythonSelectSelector
elif _can_allocate('kqueue'): elif _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector _DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('devpoll'): elif _can_allocate('devpoll'):
_DEFAULT_SELECTOR = DevpollSelector _DEFAULT_SELECTOR = DevpollSelector
elif _can_allocate('epoll'): elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector _DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'): elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector _DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'): elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector _DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine else: # Platform-specific: AppEngine
raise RuntimeError('Platform does not have a selector.') raise RuntimeError('Platform does not have a selector.')
return _DEFAULT_SELECTOR() return _DEFAULT_SELECTOR()