view hgext/fsmonitor/pywatchman/compat.py @ 42961:460f8bf58020

osutil: allow disabling setprocname via a define passed to the compiler

In some situations, we run a custom python launcher that appears to not set up
Py_GetArgcArgv correctly. We then proceed to promptly crash when we attempt to
dereference NULL. Being able to completely disable setprocname is beneficial in
these situations, since we won't even attempt to use it, even if the case that
causes the crash is fixed.

Right now, if I compile osutil.so with -DSETPROCNAME_USE_NONE, the compilation
fails on python3 due to SETPROCNAME_USE_NONE redefinition. I could possibly
work around that, but it's likely helpful to have a way of disabling this
completely without it being brittle (i.e. if python3 ever gains the ability to
perform this operation).

Differential Revision: https://phab.mercurial-scm.org/D6865

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from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
# no unicode literals

'''Compatibility module across Python 2 and 3.'''

import sys

PYTHON3 = sys.version_info >= (3, 0)

# This is adapted from https://bitbucket.org/gutworth/six, and used under the
# MIT license. See LICENSE for a full copyright notice.
if PYTHON3:
    def reraise(tp, value, tb=None):
        try:
            if value is None:
                value = tp()
            if value.__traceback__ is not tb:
                raise value.with_traceback(tb)
            raise value
        finally:
            value = None
            tb = None
else:
    exec('''
def reraise(tp, value, tb=None):
    try:
        raise tp, value, tb
    finally:
        tb = None
'''.strip())

if PYTHON3:
    UNICODE = str
else:
    UNICODE = unicode