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
|
#
# Module to allow connection and socket objects to be transferred
# between processes
#
# multiprocessing/reduction.py
#
# Copyright (c) 2006-2008, R Oudkerk --- see COPYING.txt
#
__all__ = []
import os
import sys
import socket
import threading
import copy_reg
import _multiprocessing
from multiprocessing import current_process
from multiprocessing.forking import Popen, duplicate, close
from multiprocessing.util import register_after_fork, debug, sub_debug
from multiprocessing.connection import Client, Listener
#
#
#
if not(sys.platform == 'win32' or hasattr(_multiprocessing, 'recvfd')):
raise ImportError('pickling of connections not supported')
#
# Platform specific definitions
#
if sys.platform == 'win32':
import _subprocess
from ._multiprocessing import win32
def send_handle(conn, handle, destination_pid):
process_handle = win32.OpenProcess(
win32.PROCESS_ALL_ACCESS, False, destination_pid
)
try:
new_handle = duplicate(handle, process_handle)
conn.send(new_handle)
finally:
close(process_handle)
def recv_handle(conn):
return conn.recv()
else:
def send_handle(conn, handle, destination_pid):
_multiprocessing.sendfd(conn.fileno(), handle)
def recv_handle(conn):
return _multiprocessing.recvfd(conn.fileno())
#
# Support for a per-process server thread which caches pickled handles
#
_cache = set()
def _reset(obj):
global _lock, _listener, _cache
for h in _cache:
close(h)
_cache.clear()
_lock = threading.Lock()
_listener = None
_reset(None)
register_after_fork(_reset, _reset)
def _get_listener():
global _listener
if _listener is None:
_lock.acquire()
try:
if _listener is None:
debug('starting listener and thread for sending handles')
_listener = Listener(authkey=current_process().get_authkey())
t = threading.Thread(target=_serve)
t.setDaemon(True)
t.start()
finally:
_lock.release()
return _listener
def _serve():
from .util import is_exiting, sub_warning
while 1:
try:
conn = _listener.accept()
handle_wanted, destination_pid = conn.recv()
_cache.remove(handle_wanted)
send_handle(conn, handle_wanted, destination_pid)
close(handle_wanted)
conn.close()
except:
if not is_exiting():
import traceback
sub_warning(
'thread for sharing handles raised exception :\n' +
'-'*79 + '\n' + traceback.format_exc() + '-'*79
)
#
# Functions to be used for pickling/unpickling objects with handles
#
def reduce_handle(handle):
if Popen.thread_is_spawning():
return (None, Popen.duplicate_for_child(handle), True)
dup_handle = duplicate(handle)
_cache.add(dup_handle)
sub_debug('reducing handle %d', handle)
return (_get_listener().address, dup_handle, False)
def rebuild_handle(pickled_data):
address, handle, inherited = pickled_data
if inherited:
return handle
sub_debug('rebuilding handle %d', handle)
conn = Client(address, authkey=current_process().get_authkey())
conn.send((handle, os.getpid()))
new_handle = recv_handle(conn)
conn.close()
return new_handle
#
# Register `_multiprocessing.Connection` with `copy_reg`
#
def reduce_connection(conn):
rh = reduce_handle(conn.fileno())
return rebuild_connection, (rh, conn.readable, conn.writable)
def rebuild_connection(reduced_handle, readable, writable):
handle = rebuild_handle(reduced_handle)
return _multiprocessing.Connection(
handle, readable=readable, writable=writable
)
copy_reg.pickle(_multiprocessing.Connection, reduce_connection)
#
# Register `socket.socket` with `copy_reg`
#
def fromfd(fd, family, type_, proto=0):
s = socket.fromfd(fd, family, type_, proto)
if s.__class__ is not socket.socket:
s = socket.socket(_sock=s)
return s
def reduce_socket(s):
reduced_handle = reduce_handle(s.fileno())
return rebuild_socket, (reduced_handle, s.family, s.type, s.proto)
def rebuild_socket(reduced_handle, family, type_, proto):
fd = rebuild_handle(reduced_handle)
_sock = fromfd(fd, family, type_, proto)
close(fd)
return _sock
copy_reg.pickle(socket.socket, reduce_socket)
#
# Register `_multiprocessing.PipeConnection` with `copy_reg`
#
if sys.platform == 'win32':
def reduce_pipe_connection(conn):
rh = reduce_handle(conn.fileno())
return rebuild_pipe_connection, (rh, conn.readable, conn.writable)
def rebuild_pipe_connection(reduced_handle, readable, writable):
handle = rebuild_handle(reduced_handle)
return _multiprocessing.PipeConnection(
handle, readable=readable, writable=writable
)
copy_reg.pickle(_multiprocessing.PipeConnection, reduce_pipe_connection)
|
