annotate hgdemandimport/tracing.py @ 44153:e4344e463c0c stable 5.3rc1

packaging: rename hgrc.d to defaultrc for Windows config files next to the exe

The code and the help still says that it will read hgrc.d next to the
executable.  But this directory needs to exist to read the resource based config
files.  Otherwise even `hg version` errors out:

    $ /c/Program\ Files/Mercurial/hg.exe version
    Traceback (most recent call last):
      File "hg", line 43, in <module>
      File "mercurial\dispatch.pyc", line 110, in run
      File "mercurial\dispatch.pyc", line 226, in dispatch
      File "mercurial\ui.pyc", line 308, in load
      File "mercurial\rcutil.pyc", line 99, in rccomponents
      File "mercurial\rcutil.pyc", line 69, in default_rc_resources
      File "mercurial\utils\resourceutil.pyc", line 84, in contents
    WindowsError: [Error 3] The system cannot find the path specified: 'c:\\Program Files\\mercurial\\defaultrc\\*.*'

Differential Revision: https://phab.mercurial-scm.org/D7981

# Support code for event tracing in Mercurial. Lives in demandimport
# so it can also be used in demandimport.
#
# Copyright 2018 Google LLC.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import

import contextlib
import os

_pipe = None
_checked = False
_session = 'none'


def _isactive():
    global _pipe, _session, _checked
    if _pipe is None:
        if _checked:
            return False
        _checked = True
        if 'HGCATAPULTSERVERPIPE' not in os.environ:
            return False
        _pipe = open(os.environ['HGCATAPULTSERVERPIPE'], 'w', 1)
        _session = os.environ.get('HGCATAPULTSESSION', 'none')
    return True


@contextlib.contextmanager
def log(whencefmt, *whenceargs):
    if not _isactive():
        yield
        return
    whence = whencefmt % whenceargs
    try:
        # Both writes to the pipe are wrapped in try/except to ignore
        # errors, as we can see mysterious errors in here if the pager
        # is active. Presumably other conditions could trigger
        # problems too.
        try:
            _pipe.write('START %s %s\n' % (_session, whence))
        except IOError:
            pass
        yield
    finally:
        try:
            _pipe.write('END %s %s\n' % (_session, whence))
        except IOError:
            pass


def counter(label, amount, *labelargs):
    if not _isactive():
        return
    l = label % labelargs
    # See above in log() for why this is in a try/except.
    try:
        _pipe.write('COUNTER %s %d %s\n' % (_session, amount, l))
    except IOError:
        pass