This file is indexed.

/usr/lib/python3/dist-packages/pyngus/endpoint.py is in python3-pyngus 2.0.3-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
#    Licensed to the Apache Software Foundation (ASF) under one
#    or more contributor license agreements.  See the NOTICE file
#    distributed with this work for additional information
#    regarding copyright ownership.
#
#    Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

import logging
import proton

LOG = logging.getLogger(__name__)

_PROTON_VERSION = (int(getattr(proton, "VERSION_MAJOR", 0)),
                   int(getattr(proton, "VERSION_MINOR", 0)))


class Endpoint(object):
    """AMQP Endpoint state machine."""

    # Endpoint States:
    STATE_UNINIT = 0  # initial state
    STATE_PENDING = 1  # local opened, waiting for remote to open
    STATE_REQUESTED = 2  # remote opened, waiting for local to open
    STATE_CANCELLED = 3  # local closed before remote opened
    STATE_ABANDONED = 4  # remote closed before local opened
    STATE_ACTIVE = 5
    STATE_NEED_CLOSE = 6  # remote closed, waiting for local close
    STATE_CLOSING = 7  # locally closed, pending remote close
    STATE_CLOSED = 8  # terminal state
    STATE_ERROR = 9  # unexpected state transition

    STATE_NAMES = ["STATE_UNINIT", "STATE_PENDING", "STATE_REQUESTED",
                   "STATE_CANCELLED", "STATE_ABANDONED", "STATE_ACTIVE",
                   "STATE_NEED_CLOSE", "STATE_CLOSING", "STATE_CLOSED",
                   "STATE_ERROR"]

    # Events:
    # These correspond to endpoint events generated by the Proton Engine

    LOCAL_OPENED = 0
    LOCAL_CLOSED = 1
    REMOTE_OPENED = 2
    REMOTE_CLOSED = 3
    EVENT_NAMES = ["LOCAL_OPENED", "LOCAL_CLOSED",
                   "REMOTE_OPENED", "REMOTE_CLOSED"]

    # Endpoint Finite State Machine:
    # Indexed by current state, each entry is indexed by the event received and
    # returns a tuple of (next-state, action).  If there is no entry for a
    # given event, _ep_error() is invoked and the endpoint moves to the
    # terminal STATE_ERROR state.
    _FSM = {}
    _FSM[STATE_UNINIT] = {
        LOCAL_OPENED: (STATE_PENDING, None),
        REMOTE_OPENED: (STATE_REQUESTED, lambda s: s._ep_requested())
    }
    _FSM[STATE_PENDING] = {
        LOCAL_CLOSED: (STATE_CANCELLED, None),
        REMOTE_OPENED: (STATE_ACTIVE, lambda s: s._ep_active())
    }
    _FSM[STATE_REQUESTED] = {
        LOCAL_OPENED: (STATE_ACTIVE, lambda s: s._ep_active()),
        REMOTE_CLOSED: (STATE_ABANDONED, None)
    }
    _FSM[STATE_CANCELLED] = {
        REMOTE_OPENED: (STATE_CLOSING, None)
    }
    _FSM[STATE_ABANDONED] = {
        LOCAL_OPENED: (STATE_NEED_CLOSE, lambda s: s._ep_need_close()),
        LOCAL_CLOSED: (STATE_CLOSED, lambda s: s._ep_closed())
    }
    _FSM[STATE_ACTIVE] = {
        LOCAL_CLOSED: (STATE_CLOSING, None),
        REMOTE_CLOSED: (STATE_NEED_CLOSE, lambda s: s._ep_need_close())
    }
    _FSM[STATE_NEED_CLOSE] = {
        LOCAL_CLOSED: (STATE_CLOSED, lambda s: s._ep_closed())
    }
    _FSM[STATE_CLOSING] = {
        REMOTE_CLOSED: (STATE_CLOSED, lambda s: s._ep_closed())
    }
    _FSM[STATE_CLOSED] = {
        REMOTE_CLOSED: (STATE_CLOSED, None)
    }
    _FSM[STATE_ERROR] = {  # terminal state
        LOCAL_OPENED: (STATE_ERROR, None),
        LOCAL_CLOSED: (STATE_ERROR, None),
        REMOTE_OPENED: (STATE_ERROR, None),
        REMOTE_CLOSED: (STATE_ERROR, None)
    }

    def __init__(self, name):
        self._name = name
        self._state = Endpoint.STATE_UNINIT
        if (_PROTON_VERSION < (0, 8)):
            # The old proton event model did not generate specific endpoint
            # events.  Rather it simply indicated local or remote state change
            # occured without giving the value of the state (opened/closed).
            # Map these events to open and close events, assuming the Proton
            # endpoint state transitions are fixed to the following sequence:
            # UNINIT --> ACTIVE --> CLOSED
            self._remote_events = [Endpoint.REMOTE_OPENED,
                                   Endpoint.REMOTE_CLOSED]
            self._local_events = [Endpoint.LOCAL_OPENED,
                                  Endpoint.LOCAL_CLOSED]

    def _process_endpoint_event(self, event):
        """Called when the Proton Engine generates an endpoint state change
        event.
        """
        LOG.debug("Endpoint %s event: %s",
                  self._name, Endpoint.EVENT_NAMES[event])
        state_fsm = Endpoint._FSM[self._state]
        entry = state_fsm.get(event)
        if not entry:
            # protocol error: invalid event for current state
            old_state = self._state
            self._state = Endpoint.STATE_ERROR
            self._ep_error("invalid event=%s in state=%s" %
                           (Endpoint.EVENT_NAMES[event],
                            Endpoint.STATE_NAMES[old_state]))
            return

        LOG.debug("Endpoint %s Old State: %s New State: %s",
                  self._name,
                  Endpoint.STATE_NAMES[self._state],
                  Endpoint.STATE_NAMES[entry[0]])
        self._state = entry[0]
        if entry[1]:
            entry[1](self)

    if (_PROTON_VERSION < (0, 8)):
        def _process_remote_state(self):
            """Call when remote endpoint state changes."""
            try:
                event = self._remote_events.pop(0)
                self._process_endpoint_event(event)
            except IndexError:
                LOG.debug("Endpoint %s: ignoring unexpected remote event",
                          self._name)

        def _process_local_state(self):
            """Call when local endpoint state changes."""
            try:
                event = self._local_events.pop(0)
                self._process_endpoint_event(event)
            except IndexError:
                LOG.debug("Endpoint %s: ignoring unexpected local event",
                          self._name)
    else:
        def _process_remote_state(self):
            pass

        def _process_local_state(self):
            pass

    @property
    def _endpoint_state(self):
        """Returns the current endpoint state."""
        raise NotImplementedError("Must Override")

    # state entry actions - overridden by endpoint subclass:

    def _ep_requested(self):
        """Remote has activated a new endpoint."""
        LOG.debug("endpoint_requested - ignored")

    def _ep_active(self):
        """Both ends of the Endpoint have become active."""
        LOG.debug("endpoint_active - ignored")

    def _ep_need_close(self):
        """The remote has closed its end of the endpoint."""
        LOG.debug("endpoint_need_close - ignored")

    def _ep_closed(self):
        """Both ends of the endpoint have closed."""
        LOG.debug("endpoint_closed - ignored")

    def _ep_error(self, error):
        """Unanticipated/illegal state change."""
        LOG.error("Endpoint state error: endpoint=%s, error=%s",
                  self._name, error)