gecko-dev/extensions/python/xpcom/__init__.py
2006-01-20 05:50:28 +00:00

165 lines
6.5 KiB
Python

# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is the Python XPCOM language bindings.
#
# The Initial Developer of the Original Code is
# Activestate Tool Corp.
# Portions created by the Initial Developer are Copyright (C) 2000
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
# Mark Hammond <MarkH@activestate.com>
#
# Alternatively, the contents of this file may be used under the terms of
# either the GNU General Public License Version 2 or later (the "GPL"), or
# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
# of those above. If you wish to allow use of your version of this file only
# under the terms of either the GPL or the LGPL, and not to allow others to
# use your version of this file under the terms of the MPL, indicate your
# decision by deleting the provisions above and replace them with the notice
# and other provisions required by the GPL or the LGPL. If you do not delete
# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
#
# ***** END LICENSE BLOCK *****
#
# The XPCOM (Cross Platform COM) package.
import exceptions
# A global "verbose" flag - currently used by the
# server package to print trace messages
verbose = 0
# Map of nsresult -> constant_name.
hr_map = {}
# The standard XPCOM exception object.
# Instances of this class are raised by the XPCOM extension module.
class Exception(exceptions.Exception):
def __init__(self, errno, message = None):
assert int(errno) == errno, "The errno param must be an integer"
self.errno = errno
self.message = message
exceptions.Exception.__init__(self, errno)
def __str__(self):
if not hr_map:
import nsError
for name, val in nsError.__dict__.items():
if type(val)==type(0):
hr_map[val] = name
message = self.message
if message is None:
message = hr_map.get(self.errno)
if message is None:
message = ""
return "%d (%s)" % (self.errno, message)
# An alias for Exception - allows code to say "from xpcom import COMException"
# rather than "Exception", preventing clashes with the builtin Exception
COMException = Exception
# Exceptions thrown by servers. It can be good for diagnostics to
# differentiate between a ServerException (which was presumably explicitly thrown)
# and a normal exception which may simply be propagating down.
# (When ServerException objects are thrown across the XPConnect
# gateway they will be converted back to normal client exceptions if
# subsequently re-caught by Python)
class ServerException(Exception):
def __init__(self, errno=None, *args, **kw):
if errno is None:
import nsError
errno = nsError.NS_ERROR_FAILURE
Exception.__init__(self, errno, *args, **kw)
# Logging support - setup the 'xpcom' logger to write to the Mozilla
# console service, and also to sys.stderr, or optionally a file.
# Environment variables supports:
# PYXPCOM_LOG_FILE=filename - if set, used instead of sys.stderr.
# PYXPCOM_LOG_LEVEL=level - level may be a number or a logging level
# constant (eg, 'debug', 'error')
# Later it may make sense to allow a different log level to be set for
# the file than for the console service.
import logging
class ConsoleServiceStream:
# enough of a stream to keep logging happy
def flush(self):
pass
def write(self, msg):
import _xpcom
_xpcom.LogConsoleMessage(msg)
def close(self):
pass
def setupLogging():
import sys, os, threading, thread
hdlr = logging.StreamHandler(ConsoleServiceStream())
fmt = logging.Formatter(logging.BASIC_FORMAT)
hdlr.setFormatter(fmt)
# There is a bug in 2.3 and 2.4.x logging module in that it doesn't
# use an RLock, leading to deadlocks in some cases (specifically,
# logger.warning("ob is %r", ob), and where repr(ob) itself tries to log)
# Later versions of logging use an RLock, so we detect an "old" style
# handler and update its lock
if type(hdlr.lock) == thread.LockType:
hdlr.lock = threading.RLock()
logger.addHandler(hdlr)
# The console handler in mozilla does not go to the console!?
# Add a handler to print to stderr, or optionally a file
# PYXPCOM_LOG_FILE can specify a filename
filename = os.environ.get("PYXPCOM_LOG_FILE")
stream = sys.stderr # this is what logging uses as default
if filename:
try:
# open without buffering so never pending output
stream = open(filename, "wU", 0)
except IOError, why:
print >> sys.stderr, "pyxpcom failed to open log file '%s': %s" \
% (filename, why)
# stream remains default
hdlr = logging.StreamHandler(stream)
# see above - fix a deadlock problem on this handler too.
if type(hdlr.lock) == thread.LockType:
hdlr.lock = threading.RLock()
fmt = logging.Formatter(logging.BASIC_FORMAT)
hdlr.setFormatter(fmt)
logger.addHandler(hdlr)
# Allow PYXPCOM_LOG_LEVEL to set the level
level = os.environ.get("PYXPCOM_LOG_LEVEL")
if level:
try:
level = int(level)
except ValueError:
try:
# might be a symbolic name - all are upper-case
level = int(getattr(logging, level.upper()))
except (AttributeError, ValueError):
logger.warning("The PYXPCOM_LOG_LEVEL variable specifies an "
"invalid level")
level = None
if level:
logger.setLevel(level)
logger = logging.getLogger('xpcom')
# If someone else has already setup this logger, leave things alone.
if len(logger.handlers) == 0:
setupLogging()
# Cleanup namespace - but leave 'logger' there for people to use, so they
# don't need to know the exact name of the logger.
del ConsoleServiceStream, logging, setupLogging