804 lines
22 KiB
Python
Executable file
804 lines
22 KiB
Python
Executable file
# This file is part of Scapy
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# See http://www.secdev.org/projects/scapy for more information
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# Copyright (C) Philippe Biondi <phil@secdev.org>
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# This program is published under a GPLv2 license
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from __future__ import print_function
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import os
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import subprocess
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import collections
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import time
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import scapy.modules.six as six
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from threading import Lock, Thread
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from scapy.automaton import Message, select_objects, SelectableObject
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from scapy.consts import WINDOWS
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from scapy.error import log_interactive, warning
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from scapy.config import conf
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from scapy.utils import get_temp_file, do_graph
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class PipeEngine(SelectableObject):
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pipes = {}
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@classmethod
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def list_pipes(cls):
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for pn, pc in sorted(cls.pipes.items()):
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doc = pc.__doc__ or ""
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if doc:
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doc = doc.splitlines()[0]
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print("%20s: %s" % (pn, doc))
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@classmethod
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def list_pipes_detailed(cls):
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for pn, pc in sorted(cls.pipes.items()):
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if pc.__doc__:
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print("###### %s\n %s" % (pn, pc.__doc__))
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else:
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print("###### %s" % pn)
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def __init__(self, *pipes):
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self.active_pipes = set()
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self.active_sources = set()
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self.active_drains = set()
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self.active_sinks = set()
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self._add_pipes(*pipes)
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self.thread_lock = Lock()
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self.command_lock = Lock()
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self.__fd_queue = collections.deque()
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self.__fdr, self.__fdw = os.pipe()
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self.thread = None
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SelectableObject.__init__(self)
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def __getattr__(self, attr):
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if attr.startswith("spawn_"):
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dname = attr[6:]
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if dname in self.pipes:
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def f(*args, **kargs):
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k = self.pipes[dname]
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p = k(*args, **kargs)
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self.add(p)
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return p
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return f
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raise AttributeError(attr)
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def check_recv(self):
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"""As select.select is not available, we check if there
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is some data to read by using a list that stores pointers."""
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return len(self.__fd_queue) > 0
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def fileno(self):
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return self.__fdr
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def _read_cmd(self):
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os.read(self.__fdr, 1)
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return self.__fd_queue.popleft()
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def _write_cmd(self, _cmd):
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self.__fd_queue.append(_cmd)
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os.write(self.__fdw, b"X")
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self.call_release()
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def add_one_pipe(self, pipe):
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self.active_pipes.add(pipe)
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if isinstance(pipe, Source):
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self.active_sources.add(pipe)
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if isinstance(pipe, Drain):
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self.active_drains.add(pipe)
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if isinstance(pipe, Sink):
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self.active_sinks.add(pipe)
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def get_pipe_list(self, pipe):
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def flatten(p, l):
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l.add(p)
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for q in p.sources | p.sinks | p.high_sources | p.high_sinks:
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if q not in l:
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flatten(q, l)
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pl = set()
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flatten(pipe, pl)
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return pl
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def _add_pipes(self, *pipes):
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pl = set()
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for p in pipes:
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pl |= self.get_pipe_list(p)
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pl -= self.active_pipes
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for q in pl:
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self.add_one_pipe(q)
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return pl
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def run(self):
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log_interactive.info("Pipe engine thread started.")
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try:
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for p in self.active_pipes:
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p.start()
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sources = self.active_sources
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sources.add(self)
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exhausted = set([])
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RUN = True
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STOP_IF_EXHAUSTED = False
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while RUN and (not STOP_IF_EXHAUSTED or len(sources) > 1):
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fds = select_objects(sources, 2)
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for fd in fds:
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if fd is self:
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cmd = self._read_cmd()
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if cmd == "X":
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RUN = False
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break
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elif cmd == "B":
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STOP_IF_EXHAUSTED = True
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elif cmd == "A":
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sources = self.active_sources - exhausted
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sources.add(self)
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else:
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warning("Unknown internal pipe engine command: %r. Ignoring." % cmd) # noqa: E501
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elif fd in sources:
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try:
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fd.deliver()
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except Exception as e:
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log_interactive.exception("piping from %s failed: %s" % (fd.name, e)) # noqa: E501
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else:
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if fd.exhausted():
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exhausted.add(fd)
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sources.remove(fd)
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except KeyboardInterrupt:
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pass
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finally:
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try:
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for p in self.active_pipes:
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p.stop()
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finally:
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self.thread_lock.release()
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log_interactive.info("Pipe engine thread stopped.")
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def start(self):
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if self.thread_lock.acquire(0):
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_t = Thread(target=self.run)
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_t.setDaemon(True)
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_t.start()
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self.thread = _t
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else:
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warning("Pipe engine already running")
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def wait_and_stop(self):
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self.stop(_cmd="B")
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def stop(self, _cmd="X"):
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try:
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with self.command_lock:
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if self.thread is not None:
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self._write_cmd(_cmd)
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self.thread.join()
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try:
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self.thread_lock.release()
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except Exception:
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pass
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else:
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warning("Pipe engine thread not running")
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except KeyboardInterrupt:
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print("Interrupted by user.")
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def add(self, *pipes):
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pipes = self._add_pipes(*pipes)
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with self.command_lock:
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if self.thread is not None:
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for p in pipes:
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p.start()
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self._write_cmd("A")
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def graph(self, **kargs):
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g = ['digraph "pipe" {', "\tnode [shape=rectangle];", ]
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for p in self.active_pipes:
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g.append('\t"%i" [label="%s"];' % (id(p), p.name))
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g.append("")
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g.append("\tedge [color=blue, arrowhead=vee];")
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for p in self.active_pipes:
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for q in p.sinks:
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g.append('\t"%i" -> "%i";' % (id(p), id(q)))
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g.append("")
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g.append("\tedge [color=purple, arrowhead=veevee];")
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for p in self.active_pipes:
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for q in p.high_sinks:
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g.append('\t"%i" -> "%i";' % (id(p), id(q)))
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g.append("")
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g.append("\tedge [color=red, arrowhead=diamond];")
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for p in self.active_pipes:
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for q in p.trigger_sinks:
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g.append('\t"%i" -> "%i";' % (id(p), id(q)))
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g.append('}')
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graph = "\n".join(g)
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do_graph(graph, **kargs)
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class _ConnectorLogic(object):
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def __init__(self):
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self.sources = set()
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self.sinks = set()
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self.high_sources = set()
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self.high_sinks = set()
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self.trigger_sources = set()
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self.trigger_sinks = set()
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def __lt__(self, other):
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other.sinks.add(self)
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self.sources.add(other)
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return other
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def __gt__(self, other):
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self.sinks.add(other)
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other.sources.add(self)
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return other
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def __eq__(self, other):
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self > other
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other > self
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return other
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def __lshift__(self, other):
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self.high_sources.add(other)
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other.high_sinks.add(self)
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return other
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def __rshift__(self, other):
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self.high_sinks.add(other)
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other.high_sources.add(self)
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return other
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def __floordiv__(self, other):
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self >> other
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other >> self
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return other
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def __xor__(self, other):
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self.trigger_sinks.add(other)
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other.trigger_sources.add(self)
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return other
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def __hash__(self):
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return object.__hash__(self)
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class _PipeMeta(type):
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def __new__(cls, name, bases, dct):
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c = type.__new__(cls, name, bases, dct)
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PipeEngine.pipes[name] = c
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return c
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class Pipe(six.with_metaclass(_PipeMeta, _ConnectorLogic)):
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def __init__(self, name=None):
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_ConnectorLogic.__init__(self)
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if name is None:
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name = "%s" % (self.__class__.__name__)
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self.name = name
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def _send(self, msg):
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for s in self.sinks:
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s.push(msg)
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def _high_send(self, msg):
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for s in self.high_sinks:
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s.high_push(msg)
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def _trigger(self, msg=None):
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for s in self.trigger_sinks:
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s.on_trigger(msg)
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def __repr__(self):
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ct = conf.color_theme
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s = "%s%s" % (ct.punct("<"), ct.layer_name(self.name))
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if self.sources or self.sinks:
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s += " %s" % ct.punct("[")
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if self.sources:
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s += "%s%s" % (ct.punct(",").join(ct.field_name(s.name) for s in self.sources), # noqa: E501
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ct.field_value(">"))
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s += ct.layer_name("#")
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if self.sinks:
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s += "%s%s" % (ct.field_value(">"),
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ct.punct(",").join(ct.field_name(s.name) for s in self.sinks)) # noqa: E501
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s += ct.punct("]")
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if self.high_sources or self.high_sinks:
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s += " %s" % ct.punct("[")
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if self.high_sources:
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s += "%s%s" % (ct.punct(",").join(ct.field_name(s.name) for s in self.high_sources), # noqa: E501
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ct.field_value(">>"))
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s += ct.layer_name("#")
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if self.high_sinks:
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s += "%s%s" % (ct.field_value(">>"),
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ct.punct(",").join(ct.field_name(s.name) for s in self.high_sinks)) # noqa: E501
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s += ct.punct("]")
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if self.trigger_sources or self.trigger_sinks:
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s += " %s" % ct.punct("[")
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if self.trigger_sources:
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s += "%s%s" % (ct.punct(",").join(ct.field_name(s.name) for s in self.trigger_sources), # noqa: E501
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ct.field_value("^"))
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s += ct.layer_name("#")
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if self.trigger_sinks:
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s += "%s%s" % (ct.field_value("^"),
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ct.punct(",").join(ct.field_name(s.name) for s in self.trigger_sinks)) # noqa: E501
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s += ct.punct("]")
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s += ct.punct(">")
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return s
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class Source(Pipe, SelectableObject):
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def __init__(self, name=None):
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Pipe.__init__(self, name=name)
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SelectableObject.__init__(self)
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self.is_exhausted = False
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def _read_message(self):
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return Message()
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def deliver(self):
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msg = self._read_message
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self._send(msg)
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def fileno(self):
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return None
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def check_recv(self):
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return False
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def exhausted(self):
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return self.is_exhausted
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def start(self):
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pass
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def stop(self):
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pass
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class Drain(Pipe):
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"""Repeat messages from low/high entries to (resp.) low/high exits
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.. code::
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+-------+
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>>-|-------|->>
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>-|-------|->
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+-------+
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"""
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def push(self, msg):
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self._send(msg)
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def high_push(self, msg):
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self._high_send(msg)
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def start(self):
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pass
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def stop(self):
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pass
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class Sink(Pipe):
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"""
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Does nothing; interface to extend for custom sinks.
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All sinks have the following constructor parameters:
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:param name: a human-readable name for the element
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:type name: str
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"""
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def push(self, msg):
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"""
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Called by :py:class:`PipeEngine` when there is a new message for the
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low entry.
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:param msg: The message data
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:returns: None
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:rtype: None
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"""
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pass
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def high_push(self, msg):
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"""
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Called by :py:class:`PipeEngine` when there is a new message for the
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high entry.
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:param msg: The message data
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:returns: None
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:rtype: None
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"""
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pass
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def start(self):
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pass
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def stop(self):
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pass
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class AutoSource(Source, SelectableObject):
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def __init__(self, name=None):
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SelectableObject.__init__(self)
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Source.__init__(self, name=name)
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self.__fdr, self.__fdw = os.pipe()
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self._queue = collections.deque()
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def fileno(self):
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return self.__fdr
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def check_recv(self):
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return len(self._queue) > 0
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def _gen_data(self, msg):
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self._queue.append((msg, False))
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self._wake_up()
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def _gen_high_data(self, msg):
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self._queue.append((msg, True))
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self._wake_up()
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def _wake_up(self):
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os.write(self.__fdw, b"X")
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self.call_release()
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def deliver(self):
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os.read(self.__fdr, 1)
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try:
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msg, high = self._queue.popleft()
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except IndexError: # empty queue. Exhausted source
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pass
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else:
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if high:
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self._high_send(msg)
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else:
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self._send(msg)
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class ThreadGenSource(AutoSource):
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def __init__(self, name=None):
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AutoSource.__init__(self, name=name)
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self.RUN = False
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def generate(self):
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pass
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def start(self):
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self.RUN = True
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Thread(target=self.generate).start()
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def stop(self):
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self.RUN = False
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class ConsoleSink(Sink):
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"""Print messages on low and high entries to ``stdout``
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.. code::
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+-------+
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>>-|--. |->>
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| print |
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>-|--' |->
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+-------+
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"""
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def push(self, msg):
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print(">" + repr(msg))
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def high_push(self, msg):
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print(">>" + repr(msg))
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class RawConsoleSink(Sink):
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"""Print messages on low and high entries, using os.write
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.. code::
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+-------+
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>>-|--. |->>
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| write |
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>-|--' |->
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+-------+
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:param newlines: Include a new-line character after printing each packet.
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Defaults to True.
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:type newlines: bool
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"""
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def __init__(self, name=None, newlines=True):
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Sink.__init__(self, name=name)
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self.newlines = newlines
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self._write_pipe = 1
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def push(self, msg):
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if self.newlines:
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msg += "\n"
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os.write(self._write_pipe, msg.encode("utf8"))
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def high_push(self, msg):
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if self.newlines:
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msg += "\n"
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os.write(self._write_pipe, msg.encode("utf8"))
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class CLIFeeder(AutoSource):
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"""Send messages from python command line:
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.. code::
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+--------+
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>>-| |->>
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| send() |
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>-| `----|->
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+--------+
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"""
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def send(self, msg):
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self._gen_data(msg)
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def close(self):
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self.is_exhausted = True
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class CLIHighFeeder(CLIFeeder):
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"""Send messages from python command line to high output:
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.. code::
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+--------+
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>>-| .----|->>
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| send() |
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>-| |->
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+--------+
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"""
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def send(self, msg):
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self._gen_high_data(msg)
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class PeriodicSource(ThreadGenSource):
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"""Generage messages periodically on low exit:
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.. code::
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+-------+
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>>-| |->>
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| msg,T |
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>-| `----|->
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+-------+
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"""
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def __init__(self, msg, period, period2=0, name=None):
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ThreadGenSource.__init__(self, name=name)
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if not isinstance(msg, (list, set, tuple)):
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msg = [msg]
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|
self.msg = msg
|
|
self.period = period
|
|
self.period2 = period2
|
|
|
|
def generate(self):
|
|
while self.RUN:
|
|
empty_gen = True
|
|
for m in self.msg:
|
|
empty_gen = False
|
|
self._gen_data(m)
|
|
time.sleep(self.period)
|
|
if empty_gen:
|
|
self.is_exhausted = True
|
|
self._wake_up()
|
|
time.sleep(self.period2)
|
|
|
|
|
|
class TermSink(Sink):
|
|
"""
|
|
Prints messages on the low and high entries, on a separate terminal (xterm
|
|
or cmd).
|
|
|
|
.. code::
|
|
|
|
+-------+
|
|
>>-|--. |->>
|
|
| print |
|
|
>-|--' |->
|
|
+-------+
|
|
|
|
:param keepterm: Leave the terminal window open after :py:meth:`~Pipe.stop`
|
|
is called. Defaults to True.
|
|
:type keepterm: bool
|
|
:param newlines: Include a new-line character after printing each packet.
|
|
Defaults to True.
|
|
:type newlines: bool
|
|
:param openearly: Automatically starts the terminal when the constructor is
|
|
called, rather than waiting for :py:meth:`~Pipe.start`.
|
|
Defaults to True.
|
|
:type openearly: bool
|
|
"""
|
|
|
|
def __init__(self, name=None, keepterm=True, newlines=True,
|
|
openearly=True):
|
|
Sink.__init__(self, name=name)
|
|
self.keepterm = keepterm
|
|
self.newlines = newlines
|
|
self.openearly = openearly
|
|
self.opened = False
|
|
if self.openearly:
|
|
self.start()
|
|
|
|
def _start_windows(self):
|
|
if not self.opened:
|
|
self.opened = True
|
|
self.__f = get_temp_file()
|
|
open(self.__f, "a").close()
|
|
self.name = "Scapy" if self.name is None else self.name
|
|
# Start a powershell in a new window and print the PID
|
|
cmd = "$app = Start-Process PowerShell -ArgumentList '-command &{$host.ui.RawUI.WindowTitle=\\\"%s\\\";Get-Content \\\"%s\\\" -wait}' -passthru; echo $app.Id" % (self.name, self.__f.replace("\\", "\\\\")) # noqa: E501
|
|
proc = subprocess.Popen([conf.prog.powershell, cmd], stdout=subprocess.PIPE) # noqa: E501
|
|
output, _ = proc.communicate()
|
|
# This is the process PID
|
|
self.pid = int(output)
|
|
print("PID: %d" % self.pid)
|
|
|
|
def _start_unix(self):
|
|
if not self.opened:
|
|
self.opened = True
|
|
rdesc, self.wdesc = os.pipe()
|
|
cmd = ["xterm"]
|
|
if self.name is not None:
|
|
cmd.extend(["-title", self.name])
|
|
if self.keepterm:
|
|
cmd.append("-hold")
|
|
cmd.extend(["-e", "cat <&%d" % rdesc])
|
|
self.proc = subprocess.Popen(cmd, close_fds=False)
|
|
os.close(rdesc)
|
|
|
|
def start(self):
|
|
if WINDOWS:
|
|
return self._start_windows()
|
|
else:
|
|
return self._start_unix()
|
|
|
|
def _stop_windows(self):
|
|
if not self.keepterm:
|
|
self.opened = False
|
|
# Recipe to kill process with PID
|
|
# http://code.activestate.com/recipes/347462-terminating-a-subprocess-on-windows/
|
|
import ctypes
|
|
PROCESS_TERMINATE = 1
|
|
handle = ctypes.windll.kernel32.OpenProcess(PROCESS_TERMINATE, False, self.pid) # noqa: E501
|
|
ctypes.windll.kernel32.TerminateProcess(handle, -1)
|
|
ctypes.windll.kernel32.CloseHandle(handle)
|
|
|
|
def _stop_unix(self):
|
|
if not self.keepterm:
|
|
self.opened = False
|
|
self.proc.kill()
|
|
self.proc.wait()
|
|
|
|
def stop(self):
|
|
if WINDOWS:
|
|
return self._stop_windows()
|
|
else:
|
|
return self._stop_unix()
|
|
|
|
def _print(self, s):
|
|
if self.newlines:
|
|
s += "\n"
|
|
if WINDOWS:
|
|
wdesc = open(self.__f, "a")
|
|
wdesc.write(s)
|
|
wdesc.close()
|
|
else:
|
|
os.write(self.wdesc, s.encode())
|
|
|
|
def push(self, msg):
|
|
self._print(str(msg))
|
|
|
|
def high_push(self, msg):
|
|
self._print(str(msg))
|
|
|
|
|
|
class QueueSink(Sink):
|
|
"""
|
|
Collects messages on the low and high entries into a :py:class:`Queue`.
|
|
Messages are dequeued with :py:meth:`recv`.
|
|
Both high and low entries share the same :py:class:`Queue`.
|
|
|
|
.. code::
|
|
|
|
+-------+
|
|
>>-|--. |->>
|
|
| queue |
|
|
>-|--' |->
|
|
+-------+
|
|
"""
|
|
|
|
def __init__(self, name=None):
|
|
Sink.__init__(self, name=name)
|
|
self.q = six.moves.queue.Queue()
|
|
|
|
def push(self, msg):
|
|
self.q.put(msg)
|
|
|
|
def high_push(self, msg):
|
|
self.q.put(msg)
|
|
|
|
def recv(self, block=True, timeout=None):
|
|
"""
|
|
Reads the next message from the queue.
|
|
|
|
If no message is available in the queue, returns None.
|
|
|
|
:param block: Blocks execution until a packet is available in the
|
|
queue. Defaults to True.
|
|
:type block: bool
|
|
:param timeout: Controls how long to wait if ``block=True``. If None
|
|
(the default), this method will wait forever. If a
|
|
non-negative number, this is a number of seconds to
|
|
wait before giving up (and returning None).
|
|
:type timeout: None, int or float
|
|
"""
|
|
try:
|
|
return self.q.get(block=block, timeout=timeout)
|
|
except six.moves.queue.Empty:
|
|
pass
|
|
|
|
|
|
class TransformDrain(Drain):
|
|
"""Apply a function to messages on low and high entry:
|
|
|
|
.. code::
|
|
|
|
+-------+
|
|
>>-|--[f]--|->>
|
|
| |
|
|
>-|--[f]--|->
|
|
+-------+
|
|
"""
|
|
|
|
def __init__(self, f, name=None):
|
|
Drain.__init__(self, name=name)
|
|
self.f = f
|
|
|
|
def push(self, msg):
|
|
self._send(self.f(msg))
|
|
|
|
def high_push(self, msg):
|
|
self._high_send(self.f(msg))
|
|
|
|
|
|
class UpDrain(Drain):
|
|
"""Repeat messages from low entry to high exit:
|
|
|
|
.. code::
|
|
|
|
+-------+
|
|
>>-| ,--|->>
|
|
| / |
|
|
>-|--' |->
|
|
+-------+
|
|
"""
|
|
|
|
def push(self, msg):
|
|
self._high_send(msg)
|
|
|
|
def high_push(self, msg):
|
|
pass
|
|
|
|
|
|
class DownDrain(Drain):
|
|
r"""Repeat messages from high entry to low exit:
|
|
|
|
.. code::
|
|
|
|
+-------+
|
|
>>-|--. |->>
|
|
| \ |
|
|
>-| `--|->
|
|
+-------+
|
|
"""
|
|
|
|
def push(self, msg):
|
|
pass
|
|
|
|
def high_push(self, msg):
|
|
self._send(msg)
|