d4e8026aa8
Revert recent py3 changes under ryu/contrib, namely parts of the following commits: - commite2dfdbf580("Treatment was not enough") and - commit325c9ae9c3("Syntax level compatibility with Python 3") Because: - Some of them are broken (stream.py) - Changes like these should go to upstream Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
137 lines
3.4 KiB
Python
137 lines
3.4 KiB
Python
# Copyright (c) 2010, 2011 Nicira, Inc.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at:
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import atexit
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import os
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import signal
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import ovs.vlog
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_hooks = []
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vlog = ovs.vlog.Vlog("fatal-signal")
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def add_hook(hook, cancel, run_at_exit):
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_init()
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_hooks.append((hook, cancel, run_at_exit))
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def fork():
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"""Clears all of the fatal signal hooks without executing them. If any of
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the hooks passed a 'cancel' function to add_hook(), then those functions
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will be called, allowing them to free resources, etc.
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Following a fork, one of the resulting processes can call this function to
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allow it to terminate without calling the hooks registered before calling
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this function. New hooks registered after calling this function will take
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effect normally."""
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global _hooks
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for hook, cancel, run_at_exit in _hooks:
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if cancel:
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cancel()
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_hooks = []
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_added_hook = False
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_files = {}
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def add_file_to_unlink(file):
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"""Registers 'file' to be unlinked when the program terminates via
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sys.exit() or a fatal signal."""
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global _added_hook
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if not _added_hook:
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_added_hook = True
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add_hook(_unlink_files, _cancel_files, True)
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_files[file] = None
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def remove_file_to_unlink(file):
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"""Unregisters 'file' from being unlinked when the program terminates via
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sys.exit() or a fatal signal."""
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if file in _files:
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del _files[file]
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def unlink_file_now(file):
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"""Like fatal_signal_remove_file_to_unlink(), but also unlinks 'file'.
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Returns 0 if successful, otherwise a positive errno value."""
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error = _unlink(file)
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if error:
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vlog.warn("could not unlink \"%s\" (%s)" % (file, os.strerror(error)))
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remove_file_to_unlink(file)
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return error
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def _unlink_files():
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for file_ in _files:
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_unlink(file_)
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def _cancel_files():
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global _added_hook
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global _files
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_added_hook = False
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_files = {}
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def _unlink(file_):
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try:
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os.unlink(file_)
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return 0
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except OSError, e:
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return e.errno
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def _signal_handler(signr, _):
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_call_hooks(signr)
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# Re-raise the signal with the default handling so that the program
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# termination status reflects that we were killed by this signal.
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signal.signal(signr, signal.SIG_DFL)
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os.kill(os.getpid(), signr)
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def _atexit_handler():
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_call_hooks(0)
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recurse = False
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def _call_hooks(signr):
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global recurse
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if recurse:
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return
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recurse = True
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for hook, cancel, run_at_exit in _hooks:
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if signr != 0 or run_at_exit:
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hook()
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_inited = False
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def _init():
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global _inited
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if not _inited:
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_inited = True
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for signr in (signal.SIGTERM, signal.SIGINT,
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signal.SIGHUP, signal.SIGALRM):
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if signal.getsignal(signr) == signal.SIG_DFL:
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signal.signal(signr, _signal_handler)
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atexit.register(_atexit_handler)
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